Note: Descriptions are shown in the official language in which they were submitted.
CA 02537601 2006-02-23
HOSPITAL PATIENT SUPPORT
FIELD OF THE INVENTION
This invention relates generally to a hospital patient support and, more
particularly, to
improvements to the structure, functionality and maintenance of the patient
support.
BACKGROUND
Typical hospital patient supports are subjected to daily use by various
hospital personnel
and patients. Patients, medical professionals, maintenance staff and others
operate and
move patient supports according to the various requirements such as patient
needs, and
stresses which require sturdy components and reliable measurements.
The headboard needs to be moved or removed often for various tasks and in
emergency
situations. A removable headboard must be lightweight and sturdy so as to
facilitate easy
removal and replacement by the user. There is a need for a light, sturdy
headboard which
is easy to use and cost-effective to produce.
The footboard often is also used to hang other equipment on the top rail or
with another
device which is attached to and hangs from the footboard. The placement of
such
equipment can obscure a reading area or control panel located on the
footboard.
Furthermore, such equipment may fall off the headboard or other device,
thereby
resulting in damage. There is a need for an integral equipment holder within a
footboard
to accommodate the requirement to hang equipment but without compromising
access to
a control panel on the footboard or risking damage to the equipment.
The change in a patient's weight is recorded by medical professionals for
various reasons
at different times during a hospital stay. Scales are incorporated in patient
supports
which can weigh a load such as the patient. When load cells are used in the
patient
support, the load readings in a horizontal patient support are not the same as
those in an
articulated patient support. The location of a patient's centre of gravity has
been further
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CA 02537601 2006-02-23
used in a patient detection system, such as the system described in US
6,822,571 (the
'571 patent) which issued to Conway on November 23, 2004. In order to obtain
an
accurate weight measurement, patients who are in an articulated patient
support often
have to be repositioned to the horizontal, which is inconvenient and
disruptive. There is
a need to measure and a patient's weight on a patient support independent of
the patient
support's angular position.
Hospital patient supports currently are equipped with a number of complex
mechanical
and electrical subsystems that provide various functions such as positioning,
weight
monitoring, and other functions related to the patient's care. Despite their
inherent
complexity, these systems need to be easy to operate by the user. The ease of
use and
operation is of critical importance, particularly in emergency situations. Due
to the
complexity and required minimal downtime for these patient supports, the
status of such
systems needs to be constantly monitored, which currently is performed by
technicians in
order to ensure the desired functionality of the patient support is
maintained. This form
of monitoring and potentially diagnosis of problems with a patient support can
be both
time consuming and costly.
Early designs of adjustable patient supports often employed the concept of a
hand crank
and gearing to adjust the height of a patient support. Such manual systems
suffer from
the need for considerable physical effort to adjust the patient support
height. Other
designs include elevation systems incorporating mechanical jacks using
hydraulic piston
cylinders or screw drives to adjust the height of the hospital patient
support. Such
hydraulic systems are known to be relatively expensive and prone to leakage.
Additionally, prior mechanical systems suffer from excessive complexity,
excessive size,
a lack of load capacity, and manufacturing difficulties.
Hospital patient support siderails of the prior art comprise support arms,
which form
undesirable pinch points for users. The movement of such siderails from the
deployed to
the stowed positions is often hampered by siderail oscillations. The siderail
falls due to
gravity and the movement can jar the patient support and disturb patients.
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In addition, the patient support apparatus of the prior art relies on
batteries to provide all
power to the patient support's electronic systems. When the battery power runs
out, the
battery itself must be recharged before power can be supplied to the
electronics. This is
problematic in circumstances where the life of the battery itself has run out
or in settings
where a suitable power supply to recharge the battery is not available.
Currently, nurses and other hospital staff hang pumps (or other hospital
equipment) on
the top edge of the footboards of hospital patient supports. Since footboards
were not
designed to support the hanging of pumps (or other hospital equipment), this
current
practice reduces access to the controls on footboards, damages foot controls
and
footboards, generates patient support motions and causes damage to pumps (and
other
equipment) that fall from its hangers.
Ordinarily, there is a tendency for detached headboards or footboards placed
in an upright
position against an object or structure to slip, thereby causing the headboard
or footboard
to fall and potentially suffer damage. This is a particularly acute concern in
the situation
of a medical emergency during which headboards and footboards may need to be
removed and set aside in haste. In a busy hospital, a discarded headboard or
footboard
that has fallen to the floor creates a tripping hazard to both staff, who may
be carrying
equipment or medication and thus have an obstructed view of the floor, and
patients, who
may have compromised mobility owing to illness. Preventing slippage,
therefore,
reduces the likelihood of personal injury stemming from hastily removed
headboards and
footboards.
Therefore there is a need for a control and diagnostic system for integration
into a
multifunctional patient support that can overcome the identified problems in
the prior art
and provide the desired functionality with a reduced level of human
interaction.
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SUMMARY OF THE INVENTION
A patient support according to the present disclosure is shown in Figure 1.
The patient
support with a head end and a foot end comprises a lying surface supported by
a frame
system. It also comprises a pair of head end siderails, a pair of foot end
siderails, a
headboard, a footboard, a power system and a communication system. The frame
system
comprises a lying surface support moveably connected to a load frame by an
articulation
system providing means for pivoting sections of the lying surface support
relative to the
load frame, a head end support arm pivotally attached to the head end of the
load frame, a
mobile frame translationally attached to foot end of the load frame, an
intermediate frame
being operationally connected to the load frame by a plurality of load cells
and movably
connected to a base frame by an elevation system, the elevation system
providing a
means for raising and lowering the intermediate frame relative to a base
frame, the base
frame being supported on the floor by a plurality of caster wheels, including
a drive
wheel operatively connected to assist in movement of the patient support.
Head end siderails are coupled to the head section of the lying surface
support and may
be moved between raised and lowered positions. Foot end siderails are coupled
to the
load frame and may also be moved between raised and lowered positions. The
headboard
is removably connected to the load frame and the footboard is connected to the
mobile
frame.
A communication system is provided to communicate with and control various
functions
of the patient support. Communication system and the remainder of patient
support are
powered by an AC source or a battery source (supported by the frame system).
In one aspect the communication system operates and monitors a plurality of
linear
actuators within the articulation system to extend and retract adjustable leg
length
section, to rotate sections of the lying surface support relative to the load
frame, and
within the elevation system to move the intermediate frame relative to the
base frame.
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In another aspect the communication system comprises a control system adapted
for
controlling functionality one or more load cells and one or more tilt sensors.
The load
sensors are operatively connected to the load frame, the intermediate frame
and
electrically connected to a control unit that is configured to receive signals
from the load
sensors, said signals relating to the weight of the patient. The tilt sensors
are operatively
connected to the lying support frame and are connected to the control unit
that is
configured to receive data from the tilt sensors, said data representative of
frame tilt. The
control unit correlates the signals and data thereby providing a means for
determining
patient characteristics.
Another aspect of the communication system is to provide a diagnostic and
control
system for a patent support, having integrated therein one or more
electronically
controlled devices for providing one or more functions to the patient support,
the system
comprising: a control subsystem electronically coupled to one or more
electronically
controlled devices for transmission of data therebetween, the control system
for
controlling the functionality of the one or more electronically controlled
devices, the
control system collecting information relating to operational conditions
representative of
the one or more electronically controlled devices; and a diagnostic subsystem
electronically coupled to the control subsystem for transmission of data
therebetween, the
control subsystem activating the diagnostic subsystem upon detection of an
operational
fault relating to the one or more electronically controlled devices, said
diagnostic
subsystem for receiving information from the control subsystem and analysing
said
information using one or more evaluation routines for the determination of a
potential
source of the operational fault.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention is described with particularity in the accompanying claims. The
further
features and benefits of this invention are better understood by reference to
the following
detailed description, as well as by reference to the following drawings.
CA 02537601 2006-02-23
Figure 1 illustrates a perspective view of a patient support according to an
embodiment of
the present invention.
Figure 2 illustrates another perspective view of a patient support according
to an
embodiment of the present invention.
Figure 3 is a lateral view of a patient support according to one embodiment of
the present
invention.
Figure 4 is a perspective view of a patient support according to an embodiment
of the
present invention showing the lying surface support.
Figure S is a perspective view of a lying surface support and part of a load
frame and a
mobile frame according to one embodiment of the present invention.
Figure 6 is a perspective exploded view of a lying surface support, a load
frame and a
mobile frame according to one embodiment of the present invention.
Figure 7 is a perspective exploded view of a lying surface support and part of
an
articulation system according to one embodiment of the present invention.
Figure 8 is a side view of a lying surface support according to one embodiment
of the
present invention in an articulated position.
Figure 9 is a perspective and exploded view of the foot section of a lying
surface support
and a lying surface retainer according to one embodiment of the present
invention.
Figure 10 is a perspective and exploded view of the foot section of a lying
surface
support and a lying surface retainer according to one embodiment of the
present
invention.
Figure 11 is a perspective view of a lying surface retainer according to one
embodiment
of the present invention.
Figure 12 is a perspective view of a load frame according to one embodiment of
the
present invention.
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Figure 13 is a perspective view of a load frame within a frame system
according to one
embodiment of the present invention.
Figure 14 is a perspective view of a load frame, intermediate frame and load
cells
according to one embodiment of the present invention.
Figure 15 depicts a top view of a tilt sensor circuit and its relative
position to the head
end casing of the load frame according to one embodiment of the present
invention.
Figure 16 depicts an exploded view of a tilt sensor circuit attached to the
head end casing
of the load frame according to one embodiment of the present invention.
Figure 17 illustrates an exploded perspective view of a head end casing of a
load frame
according to one embodiment of the present invention.
Figure 18 is a perspective view of an intermediate frame according to one
embodiment of
the present invention.
Figure 19 is a side view of a patient support according to one embodiment of
the present
invention wherein the head section of the lying surface support.
Figure 20 is a partial perspective view of an articulation mechanism according
to one
embodiment of the present invention.
Figure 21 is a partial exploded perspective view of an articulation mechanism
according
to one embodiment of the present invention.
Figure 22 is a partial exploded perspective view of an articulation mechanism
according
to one embodiment of the present invention.
Figure 23 is a partial exploded perspective view of an articulation mechanism
according
to one embodiment of the present invention in relation to a load frame and an
intermediate frame.
Figure 24 is a partial exploded perspective view of an articulation mechanism
according
to one embodiment of the present invention.
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Figure 25 is a partial perspective view of an articulation actuator according
to one
embodiment of the present invention.
Figure 26 is a perspective view of a mobile frame according to one embodiment
of the
present invention.
Figure 27 is a perspective view of a mobile frame and foot end casing
according to one
embodiment of the present invention in relation to a load frame and a lying
surface
support.
Figure 28 is an exploded perspective view of a mobile frame and foot end
casing
according to one embodiment of the present invention.
Figure 29 is a partial exploded perspective view of a mobile frame and foot
end casing
according to one embodiment of the present invention.
Figure 30 is a perspective view of an actuator for the mobile frame according
to one
embodiment of the present invention.
Figure 31 is a partial perspective view of actuators in relation to a mobile
frame
according to one embodiment of the present invention.
Figure 32 is a perspective view depicting four load cells in relation to an
intermediate
frame according to one embodiment of the present invention.
Figure 33 is a partial perspective view of load cells in relation to a load
frame and an
intermediate frame according to one embodiment of the present invention.
Figure 34 is a partial exploded perspective view of a mobile frame and load
cell system
according to one embodiment of the present invention.
Figure 35 is a partial perspective view of an elevation system according to
one
embodiment of the present invention.
Figure 36 is a partial exploded perspective view of an elevation system
according to one
embodiment of the present invention showing an actuator.
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Figures 37A and 37B show a side view of a support system according to one
embodiment
of the present invention in a Trendelenburg position and in a reverse
Trendelenburg
position respectively.
Figure 38 is a perspective view of a base frame according to one embodiment of
the
present invention.
Figure 39 is an exploded perspective view of a base frame according to one
embodiment
of the present invention.
Figure 40 is a perspective view of caster wheels and a braking system
according to one
embodiment of the present invention.
Figure 41 is an exploded perspective view of caster wheels and a braking
system
according to one embodiment of the present invention.
Figure 42 is an exploded perspective view of a breaking pedal and castor wheel
according
to one embodiment of the present invention.
Figure 43 is a perspective view of a drive wheel mechanism according to one
embodiment of the present invention.
Figure 44 is a perspective view of a drive wheel mechanism according to one
embodiment of the present invention in relation to a base frame.
Figure 45 is a perspective exploded view of a drive wheel mechanism according
to one
embodiment of the present invention in relation to a base frame.
Figure 46 is a perspective exploded view of a drive wheel mechanism according
to
another embodiment of the present invention in relation to a base frame.
Figure 47A depicts a perspective external view of the spring and damper in the
raised
siderail according to one embodiment of the present invention wherein the
angle between
the arm and the mechanism is about 70 degrees.
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Figures 47B and 47C depict perspective internal and front internal views of
the siderail of
Figure 47A.
Figures 48A and 48B depict perspective internal and front internal views of
the spring
and damper in the partially raised siderail according to one embodiment of the
present
invention wherein the angle between the arm and the mechanism is about 30
degrees.
Figures 49A and 49B depict perspective internal and front internal views of
the spring
and damper in the partially lowered siderail according to one embodiment of
the present
invention wherein the angle between the arm and the mechanism is about 0
degree.
Figures SOA and SOB depict perspective internal and front internal views of
the spring
and damper in the lowered siderail according to one embodiment of the present
invention
wherein the angle between the arm and the mechanism is about -35 degrees.
Figure 51 is a front exterior view of a siderail according to one embodiment
of the
present invention in a fully raised position wherein the shape of the support
arms is
round.
Figure 52 is a front exterior view of the siderail of Figure S 1 in a
partially raised position.
Figure 53 is a front exterior view of the siderail of Figure 51 in a partially
lowered
position.
Figures 54A and 54B depict perspective internal views of right and left head-
end siderails
according to one embodiment of the present invention, wherein the siderail
control
system is shown in an exploded view.
Figure 55 shows a perspective view of the head-end siderails according to one
embodiment of the present invention in a raised position attached to the lying
surface
support.
Figure 56 depicts a perspective view of the position of the head-end siderails
according to
one embodiment of the present invention relative to the load frame.
CA 02537601 2006-02-23
Figure 57 depicts an exploded view of the head-end siderails according to one
embodiment of the present invention attached to the lying surface support.
Figure 58 depicts an exploded view of the head-end siderail components and
control
system with the lying surface support of Figure 57.
Figure 59 depicts an exploded view of the head-end siderail components and
control
system in relation to the load frame.
Figure 60 depicts an exploded view of head-end siderail components, control
system and
support arms according to one embodiment of the present invention.
Figure 61 shows a perspective view of the foot-end siderails in a raised
position attached
to the load frame according to one embodiment of the present invention.
Figure 62 shows an exploded view of the foot-end siderails of Figure 61
attached to the
load frame.
Figure 63 is a perspective view of the foot-end siderails of Figure 61 showing
an
exploded view of the right siderail and attachment to the seat section of the
load frame.
Figure 64A is a perspective internal view of the headboard according to one
embodiment
of the present invention.
Figure 64B is a perspective external view of the assembled footboard,
equipment holder
and holder support according to one embodiment of the present invention.
Figure 65 is front external view of the headboard of Figure 64A.
Figure 66 is a perspective internal view of the headboard of Figure 64A
showing an
exploded view of the caps or covers and the headboard posts.
Figure 67 is a side view of the headboard of Figure 64A.
Figure 68 is a bottom view of the headboard of Figure 64A.
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Figure 69A is a perspective exterior view of the footboard, holder support and
equipment
holder without equipment according to one embodiment of the present invention.
Figure 69B is a perspective exterior view of the footboard of Figure 69A in
relation to
equipment which comprises a hanging means.
Figure 69C is a perspective exterior view of the footboard of Figures 69 B
wherein the
equipment is hanging on the equipment holder.
Figure 70 is a perspective external view depicting the assembled footboard,
equipment
holder and holder support according to one embodiment of the present
invention.
Figure 71 is an exploded perspective view of the footboard of Figure 70.
Figure 72 depicts a power cord and plug for use as a power source according to
one
embodiment of the present invention.
Figure 73A depicts an auxiliary outlet according to one embodiment of the
present
invention.
Figure 73B is an exploded view of the auxiliary outlet of Figure 73A attached
to the load
frame.
Figure 74A is an exploded partial view of a control system attached to the
foot end casing
of the mobile frame.
Figure 74B is an embodiment of the control board detail in the control system
of Figure
74A.
Figure 74C depicts the connector position detail in Figure 74A.
Figure 75A shows an exploded partial view of a power system attached to the
head end
casing of the load frame according to one embodiment of the present invention.
Figures 75B and 75C are front and rear perspective views of the power supply
inlet
depicted in Figure 75A.
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Figure 76A shows an exploded partial view of another power system attached to
the head
end casing of the load frame according to one embodiment of the present
invention.
Figure 76B is a rear perspective view of the power supply inlet depicted in
Figure 76A.
Figure 76C is a rear perspective view of the power inlet depicted in Figure
76A.
Figure 77 depicts the functional block diagram of an accelerometer used in an
embodiment of the present invention.
Figure 78 displays a tilt sensor circuit according to an embodiment of the
present
W vention.
Figure 79A depicts a horizontal patient support with a load according to an
embodiment
of the present invention.
Figure 79B depicts an incline patient support with a load at angle 8 according
to an
embodiment of the present invention.
Figure 80 illustrates a part of a user interface embedded into a patient
support according
to an embodiment of the present invention.
Figure 81 illustrates the window content of a step in a series of user-patient
support
interaction processes displayed on a detached device such as a general purpose
computer
according to one embodiment of the present invention.
Figure 82 illustrates part of a user interface according to one embodiment of
the present
invention intended for use by a patient.
Figure 83 depicts a perspective exterior view of a footboard according to an
embodiment
of the present invention showing an partial exploded view of a control system
and
interface embodiment that does not include a scale system or patient
monitoring system.
Figure 84 depicts the footboard of Figure 83 and interface embodiment that
does not
include a scale system but which does include an embodiment of a patient
monitoring
system.
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Figure 85 depicts the footboard of Figure 83 and interface embodiment that
does not
include a scale system but which does include another embodiment of a patient
momtormg system.
Figure 86 depicts the footboard of Figure 83 and interface embodiment that
does include
a scale system but which does not include a patient monitoring system.
Figure 87 depicts the footboard of Figure 83 and interface embodiment that
does include
a scale system and one embodiment of a patient monitoring system.
Figure 88 depicts the footboard of Figure 83 and interface embodiment that
does include
a scale system and another embodiment of a patient monitoring system.
Figure 89 schematically illustrates the electrical architecture of a patient
support control
and diagnostic system according to one embodiment of the present invention.
Figure 90 illustrates a load cell system that is used for monitoring movement
and mass or
weight of a patient according to one embodiment of the present invention.
Figure 91 illustrates a motor control and drive system according to one
embodiment of
the present invention.
Figure 92 illustrates an interface controller according to one embodiment of
the present
invention.
Figure 93 illustrates a scale subsystem according to one embodiment of the
present
invention.
Figure 94 illustrates a power supply system according to one embodiment of the
present
invention.
Figure 95 illustrates a communication interface according to one embodiment of
the
present invention.
Figure 96 illustrates an embodiment of a motor control, and motor and actuator
system.
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Figure 97 illustrates an embodiment of an interface controller.
Figure 98 illustrates an embodiment of a scale or weigh subsystem.
Figure 99 illustrates a perspective view of a patient support according to an
embodiment
of the present invention.
DETAILED DESCRIPTION
The term, patient, includes any person being supported by the patient support,
and is not
restricted to patients in a hospital, but rather could mean any person laying
on the patient
support.
A patient support according to the present disclosure is shown in FIG 1. The
patient
support with a head end and a foot end comprises a lying surface supported by
a frame
system. It also comprises a pair of head end siderails, a pair of foot end
siderails, a
headboard, a footboard, a power system and a communication system. The frame
system
comprises a lying surface support moveably connected to a load frame by an
articulation
system providing means for pivoting sections of the lying surface support
relative to the
load frame, a head end support arm pivotally attached to the head end of the
load frame, a
mobile frame translationally attached to foot end of the load frame, an
intermediate frame
being operationally connected to the load frame by a plurality of load cells
and movably
connected to a base frame by an elevation system, the elevation system
providing a
means for raising and lowering the intermediate frame relative to a base
frame, the base
frame being supported on the floor by a plurality of caster wheels, including
a drive
wheel operatively connected to assist in movement of the patient support.
Head end siderails are coupled to the head section of the lying surface
support and may
be moved between raised and lowered positions. Foot end siderails are coupled
to the
load frame and may also be moved between raised and lowered positions. The
headboard
is removably connected to the load frame and the footboard is connected to the
mobile
frame.
CA 02537601 2006-02-23
A communication system is provided to communicate with and control various
functions
of the patient support. Communication system and the remainder of patient
support are
powered by an AC source or a battery source (supported by the frame system).
The Lying Surface
The patient support, with a head end and a foot end includes a lying surface
supported by
a frame system. A patient is supported on a lying surface, which can be
referred to as a
lying surface, a support surface, a lying surface, a patient surface, etc. For
the purpose of
this invention, these terms are used interchangeably to indicate the article
upon which the
patient lies, which is generally cushioned for patient comfort. The article
may be
cushioned with foam, air, springs, etc. In one embodiment of this invention,
the lying
surface is a mattress, such as found in a hospital setting. For ease of
discussion, the term
lying surface is used throughout, although another type of article defining a
lying surface
may be used.
The Frame System
The frame system includes a lying surface support moveably connected to a load
frame
by an articulation system providing means for pivoting sections of the lying
surface
support relative to the load frame, a head end support arm pivotally attached
to the head
end of the load frame, a mobile frame translationally attached to foot end of
the load
frame, an intermediate frame being operationally connected to the load frame
by a
plurality of load cells and movably connected to a base frame by an elevation
system, the
elevation system providing a means for raising and lowering the intermediate
frame
relative to a base frame, the base frame being supported on the floor by a
plurality of
caster wheels, including a drive wheel operatively connected to assist in
movement of the
patient support.
The lying surface support
The lying surface 20 (Figure 2) rests on a lying surface support 100. Figures
3 to 11
illustrate embodiments of the lying surface support 100 according to the
present
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CA 02537601 2006-02-23
invention. As can be easily appreciated from Figures 3 to 7, lying surface
support 100
can comprise several sections, such as a head section 102, a seat section 104,
a thigh
section 106 and a foot section 108. These sections are named after the body
part of a
patient lying on a lying surface 20 during normal use of the patient support
10. It would
be understood by a worker skilled in the art that the lying surface support
100 could be
comprise of more or fewer sections without departing from the scope of the
present
invention. The connection between sections of lying surface support 100 are
hinged in
order to allow lying surface support 100 to be pivotally articulated and
accommodate
different positioning needs of the patient of for treatment. Articulating
means 120
(Figures 6 and 7) are provided for the pivotal articulation of lying surface
support 100.
Some sections of the lying surface support 100 are operatively connected to an
articulation system 300, which will be discussed below. A lying surface
retainer 180
(Figures 7, 9 to 11) is provided on the foot section 108 of the lying surface
support 100 to
prevent the longitudinal movement of the lying surface 20 in relation to the
patient
support 10. According to one embodiment of the present invention, ancillary
lying
surface retainers 182 (Figures 6 and 7) are also provided prevent the lateral
movement of
the lying surface 20 in relation to the patient support 10.
Often it is required to configure patient support 10 in a CPR configuration
which is
tailored to assist a caregiver in providing CPR to the patient supported on
patient support
10. In one illustrative example, a CPR configuration is defined by placing
head section
102, seat section 104, thigh section 106 and foot section 108 of the lying
surface support
100 in a generally linear and horizontal relationship (for example as in
Figure 3). In a
further illustrative CPR configuration, head section 102, seat section 104,
thigh section
106 and foot section 108 of the lying surface support 100 are placed in a
generally linear
relationship, and lying surface support 100 is oriented such that head end 11
is lower
relative to foot end 12, generally known as a Trendelenburg position as shown
in Figure
37A for example. Such a position will be described below in the section
dealing with
elevation system 600.
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The Load Frame
In reference now to Figures 12 to 17, embodiments of a load frame 200
according to the
present invention are depicted. Figure 13 illustrates a load frame 200
incorporated in a
frame system 30. As can be clearly viewed in Figure 14, load frame 200
comprises a
head end casing 210 and two superior components 201 extending longitudinally
therefrom in a substantially parallel manner. Two inferior components 202 are
permanently affixed to the bottom surface of said two superior components 201.
Figures 15 and 16 depict a top view of a tilt sensor circuit 265 within a tilt
censor 260 and
their relative position to the head end casing 210 of the load frame 200
according to one
embodiment of the present invention. The load frame 200 supports, directly or
indirectly,
the various components of the patient support 10 located above the load frame
200.
Figure 17 shows an exploded perspective view of a head end casing 210 of a
load frame
200 according to one embodiment of the present invention comprising footboard
extrusions 212, accessory extrusions 214 and wall protecting wheels 216.
Figures 14, 23, and 32 to 34 depict load cells 250 that are operatively
connected to the
load frame 200. In one embodiment depicted in Figure 32, four load cells 250
are within
the frame system 30. The load cells 250 are respectively located proximate to
the four
corners of the intermediate frame 500, said intermediate frame 500 being
operatively
connected to the load frame 200 via the four load cells 250. More
specifically, the load
cells 250 are coupled with the respective ends of the superior components 501
of the
intermediate frame 500 and with complementary areas on the inferior components
202 of
the load frame 200. The superior components 501 of the intermediate frame 500
and the
inferior components 202 of the load frame 200 are longitudinally adjacent but
are not in
contact, the sole physical connection between these components being through
the load
cells 250.
A detailed description of the load cells 250 functionality as contemplated
within the
present invention is provided in an ulterior section below.
18
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The lying surface support 100 and its respective components (head section 102,
seat
section 104, thigh section 106 and foot section 108) described above are also
supported
by load frame 200. In one embodiment, the head section 102 and thigh section
106 are
respectively operatively connected to a head section support arm 350 (Figures
13 and 21)
and a thigh section support arm 322. The head section support arm 350 and a
thigh
section support arm 322 are comprised in articulation 300 (discussed below)
which is
connected to the load frame 200.
The two superior components 201 extending longitudinally from head end casing
210 of
load frame 200 comprise longitudinal mating grooves 225 to allow for
translational
mating with complementary mating extensions 425 of the mobile frame 400.
The Articulation System
An articulation system 300 is provided within the frame system 30 of patient
support 10.
The articulation system 300 is designed to provide a means for the lying
surface support
100 and some or all of its respective components (for example the head section
102, seat
section 104, thigh section 106 and foot section 108) to be rotationally moved
in order to
provide a desired position for the lying surface 20 supported thereon. For
example, with
reference to the embodiment shown in Figure 21, head section support arm 350
is
attached to the bottom surface of head section 102 of lying surface support
100. Head
section actuator 310 (Figure 8) is operatively connected to head section
support arm 350
at a first end and to transverse members 510 and 512 connected to the superior
components 201 of load frame 200 at a second end. Alternatively, in another
embodiment, the second end of head section actuator 310 could be operatively
connected
to the superior components 201 of load frame 200 directly. Similarly, other
section of the
lying surface support 100 can be moved.
19
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The Mobile Frame
The mobile frame 400 (Figure 26) is as shown in Figures 6, 13 and 19 is mated
with the
load frame 200 via complementary mating extensions 425 and longitudinal mating
grooves 225 of superior components 201 of load frame 200.
The Intermediate Frame
With reference to Figures 3, 13, 14, 18 and 23, embodiments of an intermediate
frame
500 according to the present invention are depicted. Figure 18 illustrates an
intermediate
frame 500 comprising superior components 501, inferior components 502,
transverse
members 510 and 512, struts 530 and elevation actuator support arms 540 and
542. The
inferior components 502 of the intermediate frame 500 are connected by head
transverse
member 510 and foot transverse member 512. The stability of the transverse
connection
is further stabilized by the diagonal connecting struts 530 connecting head
transverse
member 510 to the head end of each inferior component 502 connecting foot
transverse
member 510 to foot end of each inferior component 502. A head elevation
actuator
support arm 540 extends outward and upward from the head transverse member 510
and
has an elevation actuator clamp 545 attached thereto on the upward transverse
aspect 560
of the head elevation actuator support arm 540. Similarly, a foot elevation
actuator
support arm 542 extends outward and upward from the foot transverse member 512
and
has an elevation actuator clamp S47 attached thereto on the upward transverse
aspect 562
of the foot elevation actuator support arm 542.
The Elevation Svstem
In reference to Figures 13, 35 and 36, an elevation system 600 for the patient
support 10
is provided. A lift arm is pivotally attached to base frame 700 at a pivot
point at one end
and to the head section at second pivot point at another end. Similarly, a
lift arm is also
attached to the other side of the base frame 700 at pivot point at one end and
to the head
section at pivot point at the other end. The lift arms can be attached to the
frame and the
head section by a bolt or other fastening means that secures the lift arms to
the frame and
the head section, while still allowing the lift arms, to pivot at the pivot
points through the
CA 02537601 2006-02-23
use of Hi-Lo actuators 610. Accordingly, transverse movement of the head
section
toward and away from the foot section will cause the respective lift arms to
rotate
together about the associated pivot points. In a similar manner, the foot
section can be
articulated with lift arms, which are pivotally attached at one end to frame
and at a distal
end thereof to foot section respectively, to provide for elevation of the foot
section with
respect to the horizontal plane of the frame. As a result, the foot section
and the head
section can be configured and positioned at various degrees of inclination
with respect to
the seat section, which is fixed in the horizontal plane.
The Base Frame
The base frame is supported by a plurality of caster wheels and an auxiliary
drive wheel,
which engage with a surface, such as a floor. The base frame supports an
elevation
system, which is coupled to the intermediate frame. The base frame also
comprises the
braking mechanism that engages with one or more caster wheels or the drive
wheel. A
suitable cover can be used to cover many or all of the base frame components
and wiring
for aesthetic and safety reasons.
The Casters
Typically a plurality of caster wheels, also known as casters, are located
proximate the
perimeter of the base frame. In one embodiment, four casters are position at
the four
corners of the base frame. The casters extend below the base frame and engage
with the
surface, such as a floor. Casters are known in the prior art.
The Drive Wheel
The drive wheel and its support structure are generally positioned near or at
the centre of
the base frame. The drive wheel extends from the support structure and
suspends
towards a surface on which the casters engage, such as a floor. Examples of
drive wheels
contemplated for use with the bed of the present invention include those
disclosed in U.S.
Pat. Nos. 6,240,579 and 6,256,812 both of which are currently assigned to the
applicant
of the present invention.
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The Head End Siderails
Head end siderails are coupled to the head section of the lying surface
support and may
be moved between raised and lowered positions.
The Foot End Siderails
Foot end siderails are coupled to the load frame? and may also be moved
between raised
and lowered positions.
The patient support apparatus comprises a headboard, a footboard, a pair of
head-end
siderails, and a pair of foot-end siderails. Head and foot-end siderails are
configured to
move between raised or deployed positions, FIGS. 47 and 48 and lowered or
stowed
positions, as shown in FIGS. 49 and 50 to permit entry and egress of patients
into and out
of the patient support apparatus. Head-end siderails are coupled to the head
section of the
deck support and may be moved between raised and lowered positions. Foot-end
siderails are coupled to the intermediate frame and may also be moved between
raised
and lowered positions. As the head section of the deck support rotates
relative to the
intermediate frame, head end siderail also rotates relative to the
intermediate frame.
Siderails include rail members and linkage assemblies coupled between 1) rail
members
and the head section of the deck support and 2) respective rail members and
the
intermediate frame, that permit the rail members to be moved between upper and
lower
positions.
The term "siderail body" is used to define the part of a siderail apparatus
designed to
ensure the patient does not fall from or exit the patient support apparatus
when the
siderail is in its fully or partially deployed positions. The term "locking
mechanism" is
used to define any mechanism configured to allow the siderail to be locked or
unlocked
in any predetermined position. The term "support arms" is used to define the
physical
components connecting the siderail body to the mechanism casing through pivots
situated
in proximity of each end of each of said support arms. The term "guiding
mechanism" is
used to define a means for guiding the siderail body through a lateral
movement of the
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siderail body towards and away from the patient support apparatus during
rotational
movement of the siderail body. The term "inside view" is used to define a view
in
relation to the siderail means the view from the side in relative proximity of
the patient
support apparatus and the term "outside view" is used to define a view from
the side
opposite to that shown in the inside view. The term "upper pivot" is used to
define a
pivot used to connect a support arm and a siderail body or siderail body
support. The
pivot connected to the other end of the support arm is defined to as a "lower
pivot". The
previous definition is not affected by the spatial position of the lower and
upper pivot
relatively to each other, as this position can change during operation of the
siderail
mechanism.
The present invention provides a movable siderail for use with a patient
support
apparatus comprising a siderail body and two or more support arms. A first end
of each
support arm is pivotally connected to the siderail body in a longitudinally
spaced apart
relationship using an upper pivot. A second end of each support arm is
pivotally
connected to a cross-member in a longitudinally spaced apart relationship
through a
lower pivot, the cross-member being coupled to the patient support apparatus,
to either
the deck support or the intermediate frame. In one embodiment, the head-end
siderail is
attached proximate the first end of the deck support and the foot-end siderail
is attached
to the seat section of the intermediate frame.
The movable siderail for use with the patient support apparatus according to
the present
invention comprises a siderail body and two or more support arms. A first end
of each
support arm is pivotally connected to the siderail body in a longitudinally
spaced apart
relationship using an upper pivot, a second end of each support arm is
pivotally
connected to a cross-member in a longitudinally spaced apart relationship
through a
lower pivot, the cross-member being coupled to either the deck support or the
intermediate frame. Each support arm is configured to have a shape with a
width greater
at the first end than at the second end thereof. The siderail body is movable
between a
deployed position and a stowed position through clock-type rotational movement
in a
plane substantially vertical and substantially parallel to the longitudinal
length of the
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patient support apparatus. As a result of the shape of the support arms, the
siderail angle
defined between each support arm and the bottom edge of the siderail body
remains
obtuse at all times during the rotational movement of the siderail body. This
configuration eliminates pinch points created between each support arm and the
bottom
edge of the siderail body, which typically occur when traditional support arms
are used.
The movable siderail for use with the patient support apparatus according to
the present
invention comprises a siderail body with two or more support arms. A first end
of each
support arm is pivotally connected to the siderail body in a longitudinally
spaced apart
relationship using an upper pivot, a second end of each support arm is
pivotally
connected to a guiding mechanism through a lower pivot operatively engaged
thereto in a
longitudinally spaced apart relationship. The guiding mechanism is coupled to
a cross-
member connected to either the deck support or the intermediate frame. Each of
the
lower pivots includes a radial protrusion configured to engage with a groove
in the
guiding mechanism. When the lower pivots are rotationally moved, the radial
protrusions
are guided by the grooves thereby creating a transverse transitional movement
of the
pivots along the pivot slots of the guiding mechanism resulting in the
transverse
movement of the siderail body towards or away from the patient support
apparatus,
during the raising or lowering movement of the siderail.
Siderail Body And Support Arms
FIG. 47B illustrates a three dimensional inside view of one embodiment of the
siderail.
The siderail body is connected to two support arms through two respective
upper pivots.
Two respective lower pivots are used to connect the other ends of the two
support arms to
a cross-member. The distinctive shape of the support arms is an example of the
configuration designed to avoid the creation of pinch points between the
support arms
and the lower side of the siderail body during movement of the siderail. FIG.
47A
illustrates an outside view of the embodiment of FIG. 47B with the siderail
body attached
to the siderail mechanism. The siderail body is coupled to a siderail body
support, and
can be replaced or changed if damaged or to suit different needs, without
having to
change the complete siderail. A release system for a locking mechanism is
shown. The
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CA 02537601 2006-02-23
location of the release system is designed according to its intended use. As
such, where it
is preferable to limit the use of the locking mechanism to the caregiver or
someone else
other that the person on the patient support apparatus, the release system can
be
configured and located on the siderail body support where it cannot be
operated by the
person on the patient support apparatus. This configuration is useful for
security and
safety reasons.
With reference to FIGS. 47C, 48B, 149B and SOB, inside views of the siderail
in
accordance with one embodiment are illustrated for different positions from a
fully
deployed position (FIG. 47C) to a fully stowed position (FIG. SOB). It can be
clearly
identified that the angle formed between each support arm and the bottom edge
of the
siderail body remains obtuse at all times during the rotational movement of
the siderail
body. The siderail body of the siderail mechanism can be made for example from
plastic
or other synthetic materials which can be molded while the siderail body
support can be
made for example of aluminum, aluminum alloys or any other material with a
desired
level of strength. These materials are provided solely as examples and the
choice of
materials used for these parts can vary according to various considerations
such as
weight, strength, appearance, durability and sturdiness for example.
The characteristics of the shape of the support arms is an important feature.
Several
shapes for the support arms can be used, with the common characteristic that
the width of
the support arms 1S greater at the upper ends (operatively connected to the
upper pivots)
than the lower ends (operatively connected to the lower pivots) so that the
angle defined
by the lower side of the siderail body (or siderail body support) and the
support arms
remains obtuse at all times during the operation of the siderail, eliminating
pinch points
during operation of the siderail.
For example, possible shapes for the support arms are triangular, trapezoidal,
round (see
for example FIGS.51-53), having sides curved in a convex or concave manner,
etc. To
have the desired effect of eliminating pinch points, the location of the
connection
between the upper ends of the support arms and the upper pivots is also
important. The
CA 02537601 2006-02-23
connection points between the upper ends of the support arms and the upper
pivots have
to be proximal to the rotational side of the support arms which faces the
rotational
movement when the siderail is moved from the deployed position to the stowed
position
as illustrated in FIGS. 47C, 48B, 49B and SOB.
FIGS. 48B and 49B are detailed inside views of the siderail at intermediate
positions.
The angle formed by the bottom edge of the siderail body and the support arms
remains
obtuse until it is eliminated when the siderail body (shown in FIGS. 49A-B) is
lowered to
a point where the upper pivots are substantially aligned horizontally to the
lower pivots.
This illustrates how the siderail body can be moved laterally towards and away
from the
center of the patient support apparatus in order to minimize the width of the
patient
support apparatus when not in use and conversely maximize the patient's
surface when in
use. Also, the vertical and lateral movement of the siderail body takes place
through a
single movement during operation of the siderail and thereby decreasing the
effort and
separate actions required for operation of the siderail.
Guiding mechanism and cross-member
FIGS. 47A-C are detailed views of the siderail in the fully deployed position
according to
one embodiment. The siderail body support is pivotally connected to two
support arms
through a pair of upper pivots. The two support arms are pivotally connected
to guiding
mechanisms through a pair of lower pivots, the guiding mechanisms operatively
connected to a cross-member. A radial protrusion located on each lower pivot
is
operatively coupled to a bearing assembly which is operatively engaged with a
groove of
the guiding mechanism. The bearing assembly operatively coupled to the radial
protrusion reduces the frictional coefficient during the operation of the
siderail
considerably diminishing the wear of the radial protrusion and the edges of
the groove.
Any kind of conventional bearing assembly can be used for this purpose. The
shape and
size of groove can vary depending on the desired lateral transitional movement
of the
lower pivots along the pivot slots of the guiding mechanism. The rotational
movement
around the lower pivots which occurs during operation of the siderail results
in the
transverse movement of the lower pivots and translates into a transverse
movement of the
26
CA 02537601 2006-02-23
siderail body support towards or away from the longitudinal centerline of the
patient
support apparatus. The distance between the siderail body support and the deck
support
or the intermediate frame is at its maximum in this deployed position. FIG.
47C
illustrates an inside view of FIG. 47A and illustrates the angle formed
between the
support arms and the siderail body being obtuse.
The characteristics of the guiding mechanism can be configured in several
ways. For
example, the guiding mechanism can be cast in a single component,
incorporating the
cross-member. It can also be machined from a single piece of material. Some of
the
advantages of such embodiments are reduced costs of production, simplified
installation
and structural integrity of the guiding mechanisms and the cross-member. The
guiding
mechanism and cross-member can also be formed from several parts. For
instance, the
areas immediately surrounding the grooves of the guiding mechanism can be made
from
parts distinct from the rest of the guiding mechanism. Given that these
sections of the
guiding mechanism are the areas which will sustain the heaviest wear due to
the friction
between the radial protrusions located on each lower pivot or the bearing
assembly
operatively coupled to the radial protrusions, it is desirable to have these
sections separate
from the rest of the guiding mechanism and the cross-member in order to
replace only the
damaged sections when needed instead of replacing the whole guiding mechanism
or
cross-member.
This aspect of the invention is also useful to replace the said sections
immediately
surrounding the grooves of the guiding mechanism to change the configuration
of the
grooves for different uses of the siderail with the same patient support
apparatus. The
shape of the guiding grooves themselves can vary to accommodate various needs
and
various lying surfaces the siderail is to be used with. For example, the
grooves can be
linear, curved, angled or a combination thereof, as long as the guiding
grooves of a
siderail are identical and have the same orientation.
The embodiment illustrated in FIGS. 47-S0, for example, has guiding grooves
which
have a substantially longitudinally linear portion followed by a curved
portion. When a
27
CA 02537601 2006-02-23
rotational force is applied to the siderail, there is no lateral movement
until the radial
protrusions engage with the curved portions of the guiding grooves. When the
radial
protrusions reach the beginning of the curved portions of the guiding grooves,
the top of
the siderail body is located lower that the side of the deck support or
intermediate frame
so that once the radial protrusions engage with the curved portions of the
guiding
grooves, the siderail body is free to translate laterally closer to the center
of the patient
support apparatus. Other embodiments where the radial protrusion and bearing
assembly
are in different positions during the lateral translation movement are also
provided. The
preceding is merely one example of possible configurations of the guiding
grooves. The
guiding grooves can have curved portions curving towards or away from the
cross-
member, or any combination of curved and linear portions. For example, a
guiding
groove can have two curved portions curving towards the cross-member separated
by a
linear portion such that a rotational force applied to the siderail body will
result in a
lateral movement translating in the siderail body being closer to the center
of the patient
support apparatus when in a fully deployed position or fully stowed position
and will
while the siderail body would be farther from the center of the patient
support apparatus
when in transitional positions.
In a further embodiment of the invention, the guiding grooves are located on
the pivot
shaft to operatively engage with one or more protrusions, coupled or no to a
bearing
assembly, extending from the inside of the pivot slot.
In one embodiment the guiding mechanism and the cross-member, or the different
components thereof, as the case may be, can be made of several materials.
Characteristics such as weight-to-strength ratio, hardness, wear resistance
and corrosion
resistance (corrosion from airborne corrosive agents, air and cleaning
solvents and bodily
fluids usually found in a hospital/medical environment) should be given
consideration
when choosing the materials to be used in the manufacturing of the guiding
mechanism
and the cross-member or the different components thereof. For example,
aluminum is
lightweight and resistant to corrosion, making a good material for the cross-
member.
However, other parts such as the areas immediately surrounding the grooves of
the
28
CA 02537601 2006-02-23
guiding mechanism and the slots of the lower pivot can be made from other
materials to
accommodate the higher frictional abrasion on such parts and therefore being
more prone
to wear. Materials with a high resistance to wear, such as steel, stainless
steels or ferrite
alloys for example, can be used for making these parts. Other parts of the
siderail
mechanism can be made from further different materials and are not limited in
any way
to the materials used for the guiding mechanism. The various parts of the
guiding
mechanism and the cross-member can comprise interlocking mechanisms provided
between the multiple parts to ensure correct alignment of these multiple parts
during
assembly. As mentioned previously, for example, the guiding grooves within a
same
guiding mechanism have to be the same for the siderail to function properly,
requiring
parts that are precisely operatively connected. Slots, grooves, apertures or
fittings, for
example, may be used to interlock the various parts of the siderail together
precisely.
With reference to FIGS. 48B and 49B, embodiments of the siderail are
illustrated in
transitional positions between a fully deployed position and a fully stowed
position. The
siderail body support is pivotally connected to two support arms through a
pair of upper
pivots. The two support arms are pivotally connected to the guiding mechanism
coupled
to the cross-member through a pair of lower pivots. A radial protrusion
located on each
lower pivot shaft is operatively coupled to a bearing assembly which is
operatively
engaged with a groove of the guiding mechanism. The bearing assembly
operatively
coupled to the radial protrusion reduces the frictional coefficient during the
operation of
the siderail considerably diminishing the wear of the radial protrusion and
the edges of
the groove. The radial protrusions are guided along the guiding grooves. The
rotational
movement around the lower pivots which occurs during operation of the siderail
results
in a transverse movement of the lower pivots and translates into a transverse
movement
of the siderail body support towards or away from the longitudinal centerline
of the
patient support apparatus. In the present embodiment, the distance between the
siderail
body support and the deck support or intermediate frame is at its maximum in
this
deployed position. Still referring to the present embodiment, the spacing
between the
support arms and the guiding mechanism of the cross-member is diminished as
the
siderail body is lowered. The rate at which the spacing between the support
arms and the
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CA 02537601 2006-02-23
cross-member is diminished and the lateral transitional movement are defined
by the size
and shape of the guiding grooves of the guiding mechanism. Variations to the
siderail
can be made in order to get relative spacing between the support arms and the
cross-
member which varies at different stages of the rotational movement of the
siderail body.
A single or several lower pivot shafts can be designed to have radial
protrusion to
operatively be coupled to a bearing assembly which is operatively engaged with
a groove
of the guiding mechanism.
The operation of the siderail is as described above and illustrated in FIGS.
47-S0. The
distance between the lower portion of the siderail body support and the deck
support or
intermediate frame is at its minimum in this fully stowed position. FIG. 49B
illustrates
the absence of an angle between the support arms and the lower edge of the
siderail body
support, and therefore the absence of pinch points.
In one embodiment, the pivot shafts of the lower pivots engaging with the
guiding
mechanism are screw-type shafts. In this embodiment, the guiding mechanism is
designed to have treads matching the radial extensions of the screw-type pivot
shafts to
operatively receive the said radial extensions creating a lateral translation
movement of
the pivot shafts through a rotation of the pivot shafts. The lateral
translation movement is
away or towards the guiding mechanism depending on the orientation of the
rotational
movement applied to the shafts. Using this type of screw-type pivot shaft, one
or more
lower pivot shafts can be designed to have radial extensions to operatively be
coupled to
a bearing assembly which can be operatively engaged with treads of the guiding
mechanism.
In one embodiment the pivot journals or journal bearings can be used between
the pivots
shafts and their corresponding pivot slots. The pivot journals or journal
bearings help
reduce significantly the wearing of the pivot shafts and the corresponding
pivot slots
while also reducing high contact stresses and strain. Within the parameters of
the
embodiments of the present invention, this is especially useful when applied
to the upper
CA 02537601 2006-02-23
pivots since they sustain the heaviest strain during operation of the siderail
mechanism
due to their relational position from the lying surface.
During operation of the siderail mechanism according to an embodiment of the
present
invention, a rotational force is applied to the siderail body. However, while
operating the
siderail mechanism, there will always be a certain amount of substantially
longitudinal
force applied to the mechanism possibly resulting in binding at the pivot
points. This can
happen as a result of the application of a force to the siderail that is not
aligned with the
rotation centered with the lower pivots. In order to address and minimize such
a result,
an embodiment provides a first upper pivot slot being slightly oblong-shaped
while' the
second upper pivot slot is circular. This feature is particularly advantageous
for one hand
operation of the siderail where the force applied to the siderail will likely
not be aligned
with the rotational movement of the siderail.
Locking mechanism
In an embodiment the siderail includes a locking mechanism configured to allow
the
siderail apparatus to be locked in a specific position. The locking mechanism
includes a
locking arm pivotally mounted on the siderail body support at a first end and
having a
locking tooth at a second end. The locking arm is biased downwardly by a
spring for the
locking tooth to engage with a locking cog mounted on the shaft of one upper
pivots.
The position in which the siderail body is locked is determined by the
position of the
locking cog mounted on the shaft of one upper pivots. The locking mechanism
includes a
one hand lock release mechanism to unlock the siderail from its locked
position to permit
the moving of the siderail body.
Damper mechanism
In one embodiment the movable siderail apparatus incorporates a damper
mechanism.
FIGS. 47-50 illustrate various views of the damper when the angle between the
support
arm and the cross-member (also called the siderail angle) is 70, 30, 0 and -35
degrees
respectively. As the angle diminishes, the siderail body lowers relative to
the cross-
member. The cross-member is fixed to either the deck support (for the head-end
siderail)
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CA 02537601 2006-02-23
or the intermediate frame (for the foot-end siderail) and therefore may not
move when the
siderail body moves.
The damper mechanism comprises a spring, link member and damper operatively
connected with the cross-member of the siderail. One end of the spring is
coupled to the
cross-member and the other end is coupled to the link member. The link member
is
coupled to the cross-member with links that move proportionally to the
rotation of the
support arms. One end of the damper is coupled to the cross-member and the
other end is
coupled to a link.
The damper mechanism facilitates the downward, lowering movement of the
siderail
body. The damper mechanism prevents the siderail body from descending to a
lower
position at an undesired fast rate due to the gravitational force acting on
the siderail body.
The skilled worker will appreciate that the tension in the spring changes with
movement
of the siderail body and damper. For example, as the siderail body descends,
the link
member displaces longitudinally, thereby increasing tension in the spring.
Based on the shape of the support arm and the angle it forms with the cross-
member, the
siderail angle may vary at any given point. In this embodiment, as can be seen
in FIGS.
47A-C, when the siderail body is fully raised or deployed, the siderail angle
is about
degrees and the damper is fully open. At this point, there is minimal tension
in the
spring.
As the siderail body lowers to a partially deployed position (see FIGS. 48A-B)
the
siderail angle decreases to about degrees, and the link member is displaced
horizontally.
The damper is partially open at this point.
FIGS. 49A-B depict a siderail angle of about 0 degrees at which point the
siderail body is
in a partially stowed position. The link member has displaced even further and
the
damper is partially closed.
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FIGS SOA-B depict the siderail body in a fully stowed position. The siderail
angle is
about 35 degrees past the horizontal and the damper is fully closed. Since the
link
member is at its maximum displacement, the tension in the spring is at its
highest.
The magnitude of effect on the lowering movement is called the damping
coefficient.
For the adjustability of the damping coefficient, the stiffness of the
material in the
damper may be adjusted, thereby impacting the damper's degree of damping. The
illustrated damper mechanism can use elastomeric pads which may be identified
by color
coding corresponding to the desired damping coefficient. As the damper
mechanism of
the illustrated embodiments are installed in the siderail mechanism to dampen
the
downward motion of the siderail body (ie: attenuating the force of gravity on
the
siderail), the range of desired damping coefficients is not large.
The damper mechanism can further act as a shock absorber by decreasing the
amplitude
of the mechanical oscillations (up and down movement) of the spring. As such,
the
damper mechanism eliminates or progressively diminishes the vibrations or
oscillations
of the siderail body, thereby resulting in a smooth movement from the fully
deployed to
the fully stowed positions.
There are many advantages associated with the use of a damper mechanism with
the
siderail movement, such as achieving a smoother movement of the siderail body,
improving the feel for the user of the siderail, eliminating noise and
possible damage or
injury caused when a siderail body is dropped from the raised position and
improving the
feel of quality of the siderail.
Relative positioning of siderail
In various embodiments, the siderail or siderails are positioned on a first
side of the
patient support apparatus and can be designed to operate in a mirror fashion
to the
siderail or siderails located on the other side of the patient support
apparatus, where the
siderail on one side of the lying surface would operate in the opposite
rotational direction
(clock-wise/counter clock-wise) to the corresponding siderail on the other
side of the
33
CA 02537601 2006-02-23
patient support apparatus and where the longitudinal movement of the siderail
bodies
along the length of the patient support apparatus would be in the same
direction.
Alternatively, a patient support apparatus can have other configurations such
as one
siderail on one side and two siderails on the other. When a patient support
apparatus
comprises two siderails on a single side thereof, the relative rotational
movement of these
two siderails would be opposite in order to avoid impact therebetween, for
example when
only one of the two siderails is moved between a raised and lowered position
and vice
versa. A single patient support apparatus can have siderails of different
shapes and sizes.
The Headboard and the Footboard
The headboard is removably connected to the load frame. The footboard is
connected to
the mobile frame. The headboard and footboard according to one embodiment of
the
present invention are individually molded using a gas-assist injection molding
process.
Gas-assist injection molding is a well-known process that utilizes an inert
gas (normally
nitrogen) to create one or more hollow channels within an injection-molded
plastic part.
During the process, resin such as polypropylene is injected into the closed
mold. It is
understood that any other suitable material, such as ABS, nylon, or any other
resin
compatible with the process may be used. At the end of the filling stage, the
gas such as
nitrogen gas is injected into the still liquid core of the molding. From
there, the gas
follows the path of the least resistance and replaces the thick molten
sections with gas-
filled channels. Next, gas pressure packs the plastic against the mold cavity
surface,
compensating for volumetric shrinkage until the part solidifies. Finally, the
gas is vented
to atmosphere or recycled. Advantages to using such a process over other
molding
processes are known to a worker skilled in the art.
The headboard is made of one piece. Figures 65-68 depict the headboard of one
embodiment. The mold is designed to produce a curved removable headboard which
is
sturdy, very light, and easy to access and manipulate by the user.
Typically, medical professionals require access to the head section of a
hospital patient
support to position equipment proximate to the patient's head. In urgent
situations, such
as when the patient requires immediate medical attention, immediate access to
the head
34
CA 02537601 2006-02-23
section is often required. In both such situations, the headboard must be
moved away
from the access area or completely removed from the patient support. For a
headboard
that is removed from the patient support, it is desirable that such headboard
be as light as
possible, while still maintaining sufficient structural integrity. Once
removed from the
patient support, the headboard is typically place within the near vicinity,
such as by
leaning against a support surface such as a wall proximate to the patient
support.
Since the headboard of the present invention is a one-piece unit, it is less
costly to
manufacture than headboards which have multiple parts and require assembly.
With no
additional parts to attach to the headboard, there are also fewer parts that
are subject to
mechanical failure.
The design of the headboard mold, and thus the patient support's headboard, is
unique.
The headboard has a generally rectangular shape. A generally tubular channel,
which is
hollow, borders the headboard at both sides and the top tapering inwards
towards the
bottom and ending in two ends which project below the generally rectangular
portion of
the headboard. Proximate to each end is a generally oval post for removably
mounting
the headboard into mounting sockets (not shown) which are affixed to the
patient support
proximate the top of the head section. Optionally, in order for the headboard
to avoid
being damaged when it is resting on the floor against a wall for example, a
cap or cover,
made of a non-stick material such as rubber, can be fitted around each post.
Additionally,
the cap may ensure a snug fit into the mounting sockets and minimize wear on
the posts.
The cap can be attached to or molded into the headboard.
The generally rectangular portion of the headboard comprises a flat thin layer
of resin or
headboard skin which joins the tubular channel. In one embodiment of the
present
invention, the headboard skin has a thickness of about 1/8 inch. It will be
appreciated
that the thickness of the headboard skin and tubular channel is proportional
to the amount
of material required and the weight of the headboard. The headboard can also
be
translucent or transparent for easier monitoring of the patient and better
visibility.
The headboard has a gradual concave shape such that when the posts are fitted
into the
mounting sockets, the centre of the headboard skin is furthest from the
patient support's
CA 02537601 2006-02-23
head section. Given that the headboard is formed by a process which uses a
minimal
amount of resin, the concave shape provides additional stability to the
headboard.
In operation, users, such as medical professionals, can seize the tubular
channel at both
sides of the headboard and lift upwards for removal of the headboard.
Installation
requires lining up over and inserting each post inside the mounting sockets.
Optionally,
one or more holes of various shapes and sizes can be located within the skin
to allow
users to conveniently grasp the headboard prior to removal or installation.
Figures 69 - 71 depict the footboard of the present invention. The footboard
is formed
using a similar gas-assist injection molding process as the headboard. The
footboard also
has a generally rectangular shape. A generally tubular channel which is
hollow, borders
the footboard at both sides and the top tapering inwards towards the bottom
and ending in
two ends which project below the generally rectangular portion of the
footboard.
Proximate to each end is a generally oval post for removably mounting the
footboard into
mounting sockets which are affixed to the patient support. Similar to the cap
used with
each post of the headboard, a cap can be fitted around each post.
The generally rectangular portion of the footboard is a thin layer of resin or
footboard
skin which joins the tubular channel. Optionally, one or more holes of various
shapes
and sizes can be located within the skin to allow users to conveniently grasp
the
footboard prior to removal or installation.
The footboard is molded to be attached to two additional components, a control
board
(not shown) at board zone and a holder support. Since a control board is
attached to the
footboard a back panel needs to be attached to the footboard to secure and
protect the
control board's electronic components. The control board has a display or
console with
which the user can interface.
The console can be of any shape or size. The board zone is generally
structured to
complement the interface. Users such as medical professionals, require an
unobstructed
view and access to the console. In one embodiment, a generally rectangular
control
board and console can be located at the board zone in the upper middle half of
the
36
CA 02537601 2006-02-23
footboard. The console may optionally be positioned at an angle relative to
the vertical
such that a user peering down at the console from a position above is afforded
an
unobstructed perspective of the console.
Below the console, generally in the lower middle half of the footboard is the
holder
support comprising a horizontally disposed equipment holder bar. The holder
support is
connected to the footboard such as with screws adhesive or other connection
means. The
holder bar is useful to hang extra equipment. As required, equipment such as
pumps can
be temporarily positioned on the holder bar as opposed to the top edge of the
footboard
which could otherwise obstruct the view and access to the console. In
addition, use of the
holder bar to hang equipment which is located lower than and away from the
interface
minimizes the risk of damage to the console and footboard. Such equipment can
freely
hang. Using the holder bar to hang equipment also results in less motion
generated on
the patient support which could otherwise disrupt the patient. Additional
advantages to
users are readily apparent including reducing the risk of damaged equipment
which
previously was hung on the top edge of the footboard and would subsequently
fall or
slide off.
In one embodiment shown in Figures 69A to 69C, the holder bar is directly
attached to
the footboard.
In another embodiment the holder bar is molded as part of the footboard. The
holder bar
is almost in line with the opening of the handles. By doing that, the handles
and the
holder bar can be used simultaneously to hang equipment.
The Power System
The Communication system and the remainder of patient support are powered by
an AC
source or a battery source.
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CA 02537601 2006-02-23
The Communication System
A communication system is provided to communicate with and control various
functions
of the patient support. In one aspect the communication system comprises one
or more
load cells and one or more tilt sensors for compensating weight measurements
when the
patient support is articulated. For example, one or more load cells to measure
the weight
on the patient support are located in positions where the load can be read.
Loads cells and tilt sensors
One difficulty with determining the patient's weight occurs when the patient
support is
articulated or at positions other than the horizontally flat base position at
which the load
cells are usually calibrated. For example, when the lying surface support is
angled in
respect of the horizon or is articulated at various angles, the raw
measurements on typical
load cells will not reflect a patient's accurate weight since the load's
center of gravity
shifts, thereby affecting the individual load signals sensed by each load
cell. An
inclinometry method to determine the angular position of a patient by way of
gravitational accelerometers. When an accelerometer is in a stationary
position, the only
force acting on it is the vertical gravitational force having a constant
acceleration.
Accordingly, the angular position of the patient can be calculated by
measuring the
deviation in the inclination angle between the inclination axis and the
vertical
gravitational force. Although the accelerometers can provide an effective way
to
measure the inclination in the patient's position, the resolution of the
gravitational
accelerometers is restricted to a limited range of inclination angles. The
resolution of the
angular position of a patient can however be improved by using dual axis (X-Y)
accelerometers to sense the inclination angle with a higher degree of accuracy
over a
broader range of inclination. Advantageously, the gravitational accelerometers
can be
orientated in a variety of mounted angles, independent of any reference to
other
components of the patient support. As a result, a particular accelerometer can
be
positioned such that its effective resolution specifically targets the
anticipated range of
inclination for a given application.
38
CA 02537601 2006-02-23
To provide a more complete assessment of a patient's position, a plurality of
gravitational
accelerometers can be located in various parts of the patient support, for
example
connected to the load frame, the mobile frame, the head, seat, thigh and foot
sections of
the lying surface support. Output from the plurality of accelerometers can be
compiled to
provide a three-dimensional view of the patient's position. The angular
inclination
readings from the X-axis channel or the Y-axis channel of an accelerometer can
be
independently selected. Moreover, the sensed inclinations can be used to
complement
measurements from other sensors in the bed, such as load cells. In one
embodiment of
the present invention, monolithic gravitational accelerometers are employed to
further
reduce the inaccuracies associated with mechanical sensors.
As described above and refernng to Figures 23, 32, 33 and 34, load cells 250
can be
positioned at one or more locations in the frame system 30 of the patient
support 10 such
that measurements of various load signals can be achieved. Load cells 250
generate load
signals indicative of forces applied to the load cells 250.
Accurate load cell 250 readings are important for various reasons such as
determining the
weight fluctuations of a patient over time and the patient's center of gravity
at any given
hme.
Figure 32 illustrates one embodiment of the present invention wherein four
load cells 250
are within the frame system 30. The load cells 250 are respectively located
proximate to
the four corners of the intermediate frame 500, said intermediate frame 500
being
operatively connected to the load frame 200 via the four load cells 250. More
specifically, the load cells 250 are coupled with the respective ends of the
superior
components 501 of the intermediate frame 500 and with complementary areas on
the
inferior components 202 of the load frame 200. The superior components 501 of
the
intermediate frame 500 and the inferior components 202 of the load frame 200
are
longitudinally adjacent but are not in contact, the sole physical connection
between these
components being through the load cells 250.
In a patient support 10 according to one embodiment of the present invention,
the load
cell 250 measurements can be used together with other measured or input
information,
39
CA 02537601 2006-02-23
such as the articulation angle of a section of the lying surface support 100
or the entire
load frame 200 in order to determine, for example, a patient's weight. For
example,
when the patient support 10 is angled to the Trendelenburg and reverse
Trendelenburg
positions, the actual load can be calculated by knowing the angle of the load
frame 200
and respective loads measured by each load cell 250, independent of the load
frame's 200
position. One or more tilt sensors 260 can determine the angular position of
the load
frame 200 while the load's center of gravity shifts.
Medical personnel require accurate readings of the patient's weight
independent of the
patient support's 10 articulation. Such a measurement is possible by
calculating the
patient support's 10 angle relative to baseline and load cell 250
measurements.
A tilt sensor 260, which incorporates an accelerometer 270, is attached to any
part of the
frame system 30 that can be elevated, angled and/or articulated. Figure 16
depicts an
exploded view of an embodiment of a tilt sensor circuit 265 attached to an end
of the load
frame 200.
The tilt sensor 260 provides a signal that is read and measurements are
calculated after a
given time period, such as 50 ms. It can run continuously, intermittently or
upon
command from the user, such as when components of the frame system 30 are in
an
articulated position. The tilt sensor 260 is connected to at least one
motherboard,
processor or any electronic board via a communications network, fibre optic,
or wireless
connection to allow for a reading of the tilt sensor signal.
In one embodiment, the tilt sensor 260 is designed with a solid state
accelerometer 270,
such as the ADXL202E accelerometer from Analog Devices, Inc. of One Technology
Way, Norwood, MA, schematically represented in Figures 77 and 78. Angular
solid state
sensors or electronic angular sensors, where a change in angle of the sensor
changes the
impedance of the sensor which can be measured, could also be used. Other
accelerometers may also be used within the present invention, as would be
understood by
a worker skilled in the art to which this invention relates. The accelerometer
270 of this
embodiment is a 2-axis acceleration sensor with a direct interface to low-cost
CA 02537601 2006-02-23
microcontrollers. This interface is possible through a duty cycle (ratio of
the pulse width
to the total period) output. The outputs of the accelerometer 270 can be
analog or digital
signals whose duty cycles are proportional to acceleration. The outputs can be
directly
measured with an integrated microprocessor counter, without any external
converter.
Figure 77 depicts a functional block diagram of the accelerometer 270 used in
this
embodiment. For each axis, a circuit output converts the signal into a
modulated duty
cycle that is decoded by the microprocessor. The accelerometer 270 of this
embodiment
must be capable of measuring positive and negative accelerations to at least +-
2 g, so as
to measure static acceleration forces such as gravity and therefore be used in
a tilt sensor
260.
Theoretically, a 0 g acceleration produces a 50% nominal duty cycle.
Acceleration is
calculated as follows:
A(g) _ (T1 / T2 - 0.5) / 12.5%
T2(s) = RgET (~ ) / 125 MSS
The 12.5% corresponds to the theoretical gain of the accelerometer. When used
as a tilt
sensor 260, the accelerometer 270 uses the force of gravity as the input
vector to
determine the orientation of the object in space. The accelerometer 270 is
more sensitive
to tilt when its reading axis is perpendicular to the force of gravity, that
is to say, parallel
to the earth's surface. When the accelerometer 270 is orientated on axis to
gravity, that is
to say, near its + 1 g or - 1 g reading, the change in output acceleration per
degree of tilt
is negligible. When the accelerometer 270 is perpendicular, the output varies
nearly 17.5
mg per degree of tilt, but at 45 degrees the output only varies 12.2 mg by
degree and the
resolution declines. This is illustrated in the following table:
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CA 02537601 2006-02-23
X X90°
0° 19
y -90"
BOTTOM VIEW
X Output Y Output
X Axis ~ per (g)
OrientationDegree ~ per
to Horizonof Degree
() X Output of
(g) Tilt Y Output
(mg) (g) Tiit
(mg)
-90 -1.000 -0.2 0.000 17.5
-75 -0.966 4.4 0.259 16.9
-60 -0.866 8.6 0.500 15.2
-45 -0.707 12.2 0.707 12.4
-30 -0.500 15.0 O.B66 8.9
-15 -0.259 16.8 0.966 4.7
0 0.000 17.5 1.000 0.2
15 0.259 16.9 0.966 -4.4
30 0.500 15.2 0.866 -8.6
45 0.707 12.4 0.707 -12.2
60 0.866 8.9 0.500 -15.0
75 0.966 4.7 0.259 -16.8
90 1.000 0.2 0.000 -17.5
It is also to be noted that the gravity value varies according to the sine of
the angle, which
also influences the precision and consequently the orientation of the tilt
sensor 260 of this
embodiment. The sensor precision can be improved by using both Xout and Yout
signals
in the angular determination. By doing so, the low sensitivity range (around 0
degrees) is
reduced.
The tilt sensor circuit 265 used in one embodiment was therefore designed from
the
Analog Devices Inc. accelerometer 270 following the recommended design
parameters.
The schematic of the circuit for this embodiment is shown at Figure 78.
D 1 is added to protect the circuitry against polarity inversion.
RsaT value was set to 1 MS2. Therefore, T2 value is:
T2 = 1 MSS / 125 MSS = 0.008
T2 total period is thus 8 ms, therefore giving a 125 Hz frequency.
In order to determine the actual values of the zero and the gain, the tilt
sensor circuit 265
must be calibrated. Since the zero and the gain are known after calibration,
only T1/T2 is
42
CA 02537601 2006-02-23
unknown. It is this duty cycle that varies according to the angle. The
microprocessor
thus takes this reading and calculates the corresponding angle.
The tilt sensor circuit 265 comprises an analog potentiometer which outputs a
PWM
(pulse width modulation) signal with a good signal-to-noise ratio. This PWM
signal is
sent to a microcontroller wherein the period of the signal is measured and the
on-time of
the signals. A ratio of these results is proportional to the sine of the
angle. By using the
cosine of this angle within a formula (discussed below) the precise angle can
be
determined. This analysis can be accomplished by a microprocessor.
To calibrate the tilt sensor circuit 265, two duty cycle readings must be
taken at known
angles. With these two PWM readings, the two unknowns (zero and gain) can be
computed. It is preferable to take a PWM reading when the tilt sensor 260 is
at its zero
position, as readings are usually precise at this position. This also provides
a reading of
the PWM value corresponding to the zero of the tilt sensor 260, since a sensor
in zero
position gives 0 g.
The tilt sensors 260 of this embodiment are used to indicate the angle of the
load frame
200, such as the Trendelenburg and reverse Trendelenburg angles. A
compensation of
the weight read by the load cells 250 according to the Trendelenburg angle can
then be
computed. Consequently, the weight value displayed is thus in the required
margin.
As previously indicated, the axis in which the tilt sensor 260 is positioned
is important to
obtain precise readings. For example, the position of a head section 102 of
the lying
surface support 100 may vary between 0 and 80 degrees. Given that the tilt
sensor 260 of
the embodiment is more precise from -45 to 45 degrees than from 0 to 90
degrees, the tilt
sensor 260 would be positioned in the bed so that the zero of the sensor is at
45 degrees.
In computation, one would account for this position by adding 45 degrees to
each angle
read.
The calculation of load and calibration values is readily apparent in
referring to Figures
79A and 79B, where:
X patient load;
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CA 02537601 2006-02-23
Y+ weight of bed frame which changes with the Trendelenburg angle;
Z+ load cell factor which is not influenced by the Trendelenburg angle;
Y_ weight of bed frame which changes with the reverse Trendelenburg angle;
Z_ load cell factor which is not influenced by the reverse Trendelenburg
angle;
8 bed frame angle; and
T load cell readings.
At6=0°, To°= X+Y++Z+
Ate=12°,Tlz°=(X++Y+)cos6+Z+
During calibration, the load frame 200 without the patient is measured at
0° and at 12°,
providing:
X=0
To° = first measurement at 0°
Tlz° = second measurement at 12°
To°=Y++Z+
Tlz°=Y+cose+Z+
Y+=To°-Z+
Y+ cos 8 = Tlz° - Z+
Y+ = TIZ° - Z+
cos 8
To°-Z+=Tiz°-Z+
cos B
44
CA 02537601 2006-02-23
Z+ = T12° - To° COS a
1-COSe
if 8 = 12°
Z+ = TIZ° - To° cos 12°
1 - cos 12°
Z+ _ (T12° - To° * 0.9781 S) * 45.761565
Y+=To°-Z+
Z+ and Y+ for each load cell 250 are determined during calibration. In a
similar manner,
Z_ and Y_ are determined using measurements at 0° and -12°,
providing:
Z _ _ (T_12° - To° * 0.97815) * 45.761565
Y_=To°-Z_
When determining the patient's weight, X, the following calculations are made
for each
load cell:
Te=(X+y)cose+Z
Te=Xcos6+Ycos6+Z
Xcose=To-Ycos6-Z
X=Te-Ycose-Z
cos 8
X=To-Z
-Y
cos 8
The processor determines the load frame's 200 angular position (Trendelenburg
or
reverse Trendelenburg) prior to choosing Y+ or Y_ and Z+ or Z _. When the load
frame's
200 angle is 0°, the processor chooses Y+ and Z+ to calculate the load.
CA 02537601 2006-02-23
The center of gravity can be calculated as follows, using for example four
load cells 250
(schematically represented in Figure 90) positioned in a rectangle relative to
the patient:
X length (head to foot)
Y width (left to right)
LC(0) load cell value foot left
LC(1) load cell value head right
LC(2) load cell value foot right
LC(3) load cell value head left
W total weight of the patient
H(X) distance between the head load cells and foot load cells
H(Y) distance between the right load cells and left load cells
CG[X] - LC(3)WLC(1) * H(X) * 0.01 CG[Y] - LC(3)~LC(0) * H(Y) * 0.01
100 100
This embodiment of a load cell system 251 can be used for monitoring movement
of a
patient. The system can be integrated into the patient support 10 or can be
part of a lying
surface 20 such as a mattress. In addition, the load cell system 251 can
comprise a
number of load cells 250 or load sensors, for example a load cell 250 which
can be
embedded in the bed proximally positioned at each of a bedded person's limbs
and
optionally at the center of the patient support I0. The Ioad cell system 25I
also can be
comprised of a mesh of load cells 250 for example. The signals from the load
cells 250
can be monitored and processed by a processing unit in the load cell system
251 or a
46
CA 02537601 2006-02-23
central processing unit capable of monitoring, processing, and controlling
signals from
the patient support's 10 various subsystems. Instead of forming part of a
lying surface 20
such as a mattress the load cell system 251 can also integrated into the lying
surface
support 100. The load cell system 251 can provide a measure for the pressure,
weight, or
mass load of a certain load cell 250, for example foot left or right load cell
250 values
and head left or right load cell 250 values and additional information about
the location
of the center of gravity.
In one embodiment of the present invention, the tilt sensors 260 can provide a
means for
determining possible interference between components of the patient support
10. For
example, if a particular component is in a certain relative position, a second
component
might not be able to perform certain functions associated with it. In this
embodiment,
there can furthermore be a movement termination based on the evaluation of
tilt sensors
260 readings.
In a further embodiment of the present invention, tilt sensors 260 can be used
to evaluate
a patient's position over a period of time through the collection of angle
variation data
In one embodiment, a collection of angular data from the tilt sensors 260 can
also provide
assistance for the maintenance of the patient support 10. For example it can
help to
determine the angle of a particular patient support component and the period
of time that
that position is held, especially when a particular position results in higher
stress levels
being applied to specific components of the patient support 10.
In an another embodiment of the present invention, tilt sensors 260 can be
positioned on
the elevation system 600 for determination of the height of the patient
support surface
In an another embodiment of the present invention, tilt sensors 260 are
wireless. In a
further embodiment, tilt sensors 260 do not have an on board power supply and
are
powered in the same way as for example an RFID tag, by the scanning
frequencies sent
by a scanner for example. In another embodiment, tilt sensors 260 are
integrated within
load cells 250.
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CA 02537601 2006-02-23
A worker skilled in the art would understand that tilt sensors 260 could be
positioned in a
plurality of other components of the patient support 10, for example, the
siderails 800, a
control panel, on an intravenous apparatus support attached to a patient
support, etc.
Figure 80 illustrates a schematic view of a console, which can be part of a
user interface
embedded into a patient support. The console can be integrated into the
footboard of the
patient support illustrated in Figure 1 and provide access to the patient
support's
functions. The console has backlit zone indicators, which can indicate a set
zone mode of
the patient support for indicating a preset restriction level for movement of
an supported
person. Indicators can also be mufti-color backlit to provide an indication of
whether the
system is in an armed or a disarmed state.
Buttons can be used to set and switch between the zone alarm as indicated by
the zone
alarm indicators. Buttons can be arms or disarms the zone alarm functionality
in a
toggling fashion. Buttons can be sectional or full color or mufti-color back-
lit to indicate
an armed or disarmed state of the zone alarm system. Interface elements can be
used to
raise or lower the patient support surface. While pushing the arrow-up button
the patient
support raises and while pushing the arrow-down button the patient support
lowers.
Pushing and holding both buttons may cause the movement to stop or continue
the
movement according to the button which was pressed first. Button can lock out
some or
all functionality accessible through this or other consoles until the button
is pressed again.
Buttons and can be used to lock-out access to reorient the respective head and
knee
sections of the patient support. Button when pressed causes the patient
support to assume
a cardiac position or other predetermined shape of the patient support
surface. Each of
buttons and when pressed individually inclines or reclines the overall patient
support
surface without affecting the shape of the patient support surface. Interface
elements and
provide button groups which when pressed can reorient the head or the knee
sections of
the patient support and can be used in order to achieve respective desired
angles between
the upper body and the upper leg, as well as the upper leg and the lower leg
of an
48
CA 02537601 2006-02-23
supported person. Display can be used to display information about certain
functions or
the state of certain parts of the patient support and its system components.
Button group
can be used to scroll through information, which is available in form of a
menu for
display but exceeds the amount of information, which can be displayed
simultaneously
on display. Buttons and can be used to select or enter information and to
interact with the
menu following a command and control concept.
Figure 81 illustrates the window content of a step in a series of user-patient
support
interaction processes that can be displayed on a detached device such as a
general
purpose computer. This is part of an interface which for example can provide
remote
access to control, diagnose, or monitor functions of the patient support
system. The
interface can provide functions to select certain components from a list of
components or
subsystems of the patient support system for detailed investigation. The user
interface
may change its look and feel by changing some or all of its user interface
components
when selecting to investigate a specific component of the patient support
system. The
user interface can provide and display information in a categorized graphical
fashion and
can utilize a button status field, a motor status field, fields for monitoring
vital
information about a supported person etc. The user interface can also provide
a menu
system to select from providing access to different aspects of interaction of
the patient
support system such as for example, a monitoring interface, a maintenance
interface, an
operator interface etc. Switching between these modes may require
authorization and
may be password or security code protected.
Figure 82 illustrates an embodiment of a part of the user interface intended
for use by the
supported person. As illustrated, the user interface for the supported person
can provide
access to reclining functions, emergency call functions or control of
entertainment
eqW pment.
Figure 89 illustrates a schematic diagram of the system architecture of a
patient support
control and diagnostic system. The architecture can be divided into a number
of user
interface and control subsystem components. The system architecture comprises
a power
49
CA 02537601 2006-02-23
or AC control system for supplying electrical power, an actuator subsystem
providing
ability for positioning and orienting parts of the patient support, a number
of sensor and
detector subsystems for sensing and detecting the state of parts of the
patient support, and
a diagnostic subsystem as indicated. The diagnostic subsystem can interact
with the
sensor and detector subsystem or it can have its own redundant sensor and
detector
system. The user interface subsystem can comprise a number of control consoles
and
comprising indication or display systems. The display systems can have a touch
screen or
a regular display with separate buttons. The sensor system can comprise a
scale
subsystem including a load cell system and tilt sensor. The system
architecture can
further comprise a room or other interface for communicating information from
the
patient support to a remote user interface system or vice versa.
Figure 90 illustrates the information made available by a load cell system
265, which is
used for monitoring movement of a patient. The system can be integrated into
the patient
support or can be part of a person support element such as a lying surface. In
addition,
the load cell system can comprise a number of load cells or load sensors for
example a
load cell which can be embedded in the patient support proximally positioned
at each of a
supported person's limbs and optionally at the center of the patient support.
The load cell
system also can be comprised of a mesh of load cells for example. The signals
from the
load cells can be monitored and processed by a processing unit in the load
cell system or
a central processing unit capable of monitoring, processing, and controlling
signals from
the patient support's subsystems. Instead of forming part of a support
element, the load
cell system can be integrated into the surface of the patient support frame.
The load cell
system can provide a measure for the pressure, weight, or mass load of a
certain load cell,
for example foot left or right load cell values and head left or right load
cell values and
additional information about the location of the centre of gravity.
Figure 91 schematically illustrates an embodiment of the motor control
subsystem with a
number of attached actuators and limit switches. It is understood that,
depending on the
functionality of the patient support, there can be a different number of
actuators or limit
switches than illustrated. In this embodiment the surface of the patient
support can be
CA 02537601 2006-02-23
shaped by orienting a head, thigh, and a foot section where the support
surface for a
supported person is intended to fold and provide an adjustable angle between
the upper
body and the thigh as well as under the knee between the thigh and the lower
leg. The
head actuator can position the end of the head section, and the thigh actuator
can position
the knee section of the patient support support surface relative to an even or
flat support
structure. The HI-LO head actuator can position the head end of the even
support
structure relative to the frame of the patient support which is in contact
with the floor.
The HI-LO foot actuator can position the foot end of the even support
structure relative to
the frame of the patient support, for example. The two HI-LO actuators can
pivot the
support surface horizontally whereas the head and the thigh actuator can shape
the
support surface by pivotally adjusting sections of the patient support support
surface.
The motor control subsystem is connected to a number of limit switch or angle
sensor
systems which ensures that the actuators do not move or position parts beyond
predetermined limit angles or distances. When a part or section of the patient
support
reaches a predetermined limit position while moving, the motor control
subsystem can
receive a status change signal via one or more limit sensor signals and can
interrupt the
respective movement. The motor control subsystem can have a safety control
feature that
does not allow any further continued movement in that same direction or
orientation
unless the limit condition indicated by the limit sensor system is resolved.
Provided that
no movement of other degrees of freedom of the patient support takes place,
the limit
condition typically can be resolved by reversing the original movement.
Figure 92 schematically illustrates an embodiment of the user interface
controller with a
number of attached user interface consoles. The patient support can have a
number of
user-interface consoles, each providing access to a certain set of patient
support system
functions. For example the patient support can have user interface consoles
integrated
into one or both of the side rails of the patient support providing easy
access to certain
patient support system functions for a supported person or for a person at the
side of the
patient support. The patient support can also have a user interface console
located at the
foot or the head section of the patient support. Each such interface console
may be
S1
CA 02537601 2006-02-23
integrated into a respective foot or head board of the patient support for
example. A foot
or a head interface console may provide access to a set of patient support
system
functions different from each other as well as different from the side rail
consoles. There
can be inner or outer side rail consoles intended for access from within or
from outside of
the patient support. An embodiment of a side rail console is illustrated in
Figure 11 and
an embodiment of a foot board interface console is illustrated in Figure 9.
The foot board
console can have a display system included. The display system can be a touch
screen
display or a simple passive display system with a separate input system as
illustrated in
Figure 9. In addition the interface controller can have a remote control
interface to which
a remote console can be connected. The remote control interface can provide
wired or
wireless connection of a special purpose or a general purpose computing device
for
example. A number of different bus systems and control protocols are available
to
communicate through the remote control interface as known to a person skilled
in the art.
The interface controller may also provide a number of additional control or
remote
control interfaces.
Figure 93 illustrates a part of a scale subsystem. The scale subsystem can
connect to a
number of load sensors or load cells. The number of load sensors can be
different from
that illustrated. In this embodiment, four load sensors which are capable of
sensing
pressure and can be calibrated to provide a measure of force or mass applied
to each
sensor are attached to the scale subsystem control interface. The scale
subsystem
controller can process signals incoming from the load cells and can be used to
detect the
status of a supported person. The scale control subsystem can be configured to
provide a
messaging signal or to alert monitoring personnel through an external alarm
system
interface for example. When each load cell is properly calibrated, the scale
control
subsystem can also provide a measure of the weight of a supported person,
which is then
compensated by the angle of the patient support to provide the actual weight.
The weight
information can be utilized and can also be recorded in another subsystem of
the patient
support which may be desired for patient monitoring for example. As previously
described, the angle of the patient support and the load sensor measurements
are used to
calculate the patient's actual weight, independent of the patient support's
position.
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CA 02537601 2006-02-23
Figure 94 illustrates an embodiment of a power supply system. The power supply
system
may include an adaptation subsystem including a transformer and an adaptive
wiring and
plugging subsystem to achieve compatibility with standard power outlets and
the
different voltage standards of other regions or countries.
Figure 95 schematically illustrates the communication interface of the CAN
board
controller for communication with other components of the patient support. The
communications interface includes subinterfaces for side rail consoles,
footboard
consoles, remote monitoring consoles, external alarm system, speakers, an
entertainment
system etc.
Patient Support System Components
A multifunctional patient support can be equipped with one or more of a
plurality of
electronic devices that can provide a means for controlling the functionality
of the patient
support. For example, electronically controlled drivers or actuators can be
provided to
help automatically adjust any part or section of a patient support, wherein
these actuators
can be electrical, pneumatic or hydraulic in nature and may require a suitable
electrical,
pneumatic or hydraulic drive or power supply system for operation thereof. A
patient
support system can additionally include one or more sensors and detectors for
sensing
and detecting the status of structural or functional components of the patient
support as
well as certain vital signs of a patient. For example, sensors or detectors
can be
appropriately designed load sensors, angular movement sensors, pressure
sensors,
temperature sensors or any other type of sensor or detector that would be
appropriate for
integration into a patient support as would be readily understood by a worker
skilled in
the art. Each of these sensors or detectors can be configured to evaluate a
desired piece
of information relating to the supported person or the patient support itself,
for example
the information can relate to the mass of the patient, the orientation of the
patient support
in terms of position of the supported person or other characteristics.
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CA 02537601 2006-02-23
In addition, the patient support system comprises a form of human-machine
interface
system that can assist in accessing the functionalities that are associated
with the patient
support, for example to enable movement of portions of the patient support or
to evaluate
the condition of desired aspects of the patient support's functionality, such
as monitoring
or fault detection, for example. The interface system can be realised with one
or more
specific interfaces for enabling access, wherein interfaces can be provided on
a footboard,
headboard, side rails or other locations on the patient support for example.
The position
and number of interfaces can be determined based on the number of desired
access points
to the various functionalities of the components of the patient support.
In one embodiment, the patient support system components further comprises a
sensor
for detecting if a patient is inadvertently obstructing the selected movement
of the patient
support. For example, if a patients arm is below a side rail, a sensor can
detect the
presence of the arm and not proceed with the lowering of the side rail if this
request has
been made. In this manner, the diagnostic and control system can monitor and
evaluate if
a patient's orientation or position would inhibit a selected movement of
patient support
component.
Control Subsystem
The diagnostic and control system can comprise a single monolithic subsystem
or one or
more modular subsystems enabling the control, monitoring, and, if required,
calibration
of the electronic elements of the patient support system. In this manner the
functionality
of each of the electronic elements, for example load sensors, temperature
sensors, tilt
sensors, actuator position sensors, actuators and the like can be evaluated
and assessed
for functionality within a desired set of parameters.
The diagnostic and control system can further monitor or query the
functionality or status
of the electronic elements, including for example, actuators, load sensors and
the like.
The system can monitor the current status of the operational parameters of
these
electronic elements and cross-reference the collected data with a set of
standard
operational characteristics. In this manner the system can be provided with a
means for
detection of a potential fault or error when a specific electronic element is
not operating
54
CA 02537601 2006-02-23
within a desired and/or predetermined range. For example, if a load sensor is
being
monitored and an extraneous load reading is detected, the system can re-query
the load
sensor to evaluate if it was merely an inaccurate reading or if a potential
problem exists.
This extraneous reading may be for example a reading that may be outside of
normal
operating conditions of the load sensor or may be evaluated as extraneous upon
comparison with other load sensors in the vicinity, for example. Each of the
electronic
elements associated with the patient support system can be monitored in this
manner as
would be readily understood by a worker skilled in the art.
The diagnostic and control system can perform the monitoring of the patient
support
system components in a continuous manner, periodic manner or on-demand manner.
The
frequency of the monitoring of these components can be dependent on the
electronic
element being monitored. For example, the format of the monitoring can be
dependent
on the level of computation that is required to determine if a component is
operating
within desired and/or predetermined parameters. Constant monitoring may
include
querying the sensors for current readings for comparison with operational
parameters.
Periodic monitoring may be performed when evaluation of the orientation and
angular
position of the patient support frame is desired and on-demand monitoring may
be
performed on the diagnostic and control system itself wherein monitoring
thereof would
typically comprise a more extensive computation of current status.
In one embodiment of the present invention, the diagnostic and control system
initializes
or calibrates the operation of each of the electronic elements, for example
actuators, load
sensors and tilt sensors, in order that these electronic elements can provide
the desired
level of accuracy and desired functionality to the patient support. For
example,
calibration of a load sensor may be performed when a lying surface is
positioned on the
patient support and the load sensor can be zeroed under this condition.
Furthermore, one
or more of the actuators and tilt sensors can be calibrated or zeroed when a
patient
support is in a known orientation, for example linearly flat in a horizontal
orientation.
In one embodiment of the present invention, the diagnostic and control system,
while
providing control of the functionality of the patient support system, can
additionally
CA 02537601 2006-02-23
ensure that a procedure requested by a user is both possible and safe to be
performed. In
this scenario the diagnostic and control system can evaluate the current
status of the
patient support systems, and subsequently determine if the selected function
is possible.
For example if an operator requests the elevation of the head portion of the
patient
support, the system can determine if the head portion can be elevated, and if
this
procedure is possible, subsequently perform the desired function. If, for
example, the
head portion was fully raised, and the function was performed regardless, the
actuator
performing the requested function may be unnecessarily damaged due to
overloading or
over-extension, for example. This evaluation of the requested function can
additionally
be determined based on a current treatment being performed on a patient. For
example, if
a patient is to be oriented in a particular position, the diagnostic and
control system can
be configured to not allow any adjustment of the patient support system until
this
particular position can be changed according to treatment procedures or
requirements.
In one embodiment of the present invention, the diagnostic and control system
can be
designed using an interface-controller-model architecture. The interface can
provide user
access to functions of the patient support, as well as a query or notification
system that
can provide access to patient support functionality, or notify monitoring
personnel of
important status information about parameters of patient support functionality
in addition
to certain vital information about the supported person. The model can provide
an
abstract description of the patient support's operational parameters, for
example desired
operating conditions in the form of a virtual machine, data set or database.
The interface
and controller can also read information from the model and based on current
detected
status of the electronic elements associated with the patient support, can
determine if the
patient support is performing within desired parameters. For example, a
representational
model for a collection of loads sensors can be provided which can provide
operational
parameters for the load sensors that can additionally be representative of the
configuration of a load sensor web, thereby providing a means for evaluating
the
operational characteristics of the loads sensors during operation.
In one embodiment of the present invention, the diagnostic and control system
can
include one or more monitoring sensors that can provide a means for
independently
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CA 02537601 2006-02-23
monitoring the functionality of one or more of the functions of the patient
support. For
example, a monitoring sensor can be associated with an actuator, wherein this
monitoring
sensor can be a temperature sensor that may enable the detection of
overloading or
overuse of an actuator due to an excessive temperature reading. The diagnostic
and
control system may optionally comprise redundant sensors for example, which
may be
activated upon detection of extraneous readings for a typically used sensor.
This form of
redundancy can additionally provide a means for evaluating the operational
characteristics of the electronic elements associated with the patient
support.
In one embodiment, an interface associated with the diagnostic and control
system can
provide one or more different classes of functionalities to one or more
different
categories of users. For example functionalities can be categorized into
functions
accessible to a supported person, functions accessible to a monitoring person,
and
functions accessible to maintenance personnel for accessing diagnostic
functionality.
Consequently, there can be user interface subsystems that are available and
intended for
use by a specific user group. Functions of the patient support can also be
grouped
according to a person's physical accessibility to the patient support and can
be accessible
on-site or remotely or both. As a result, the patient support control system
can interact
with two or more physical tangible human-machine interface subsystems such as
for
example a console embedded in the patient support. Another important aspect of
the
present invention is the ability to connect to the patient support's control
subsystem and
diagnostic subsystem and transfer information therefrom or instructions
thereto via a
suitable number of user interface subsystems, for example communication
systems using
wired or wireless devices. Therefore, the diagnostic and control system
according to one
embodiment of the present invention provides the ability to obtain diagnostic
information
from the patient support via wireless devices or by connecting a computer or
other wired
communication device to the patient support. This provides an end user or a
technician a
means to access constructive information about the patient support for any
repairs or
maintenance that could be required. In a similar fashion, the monitoring
personnel or
health care provider can have access to information about the supported person
without
being in close proximity to the patient support incorporating the diagnosis
and control
system.
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CA 02537601 2006-02-23
Upon the detection of a fault or error, the diagnostic and control system can
activate an
alarm setting that can be a visual, audible or other form of fault indication.
For example,
the interface associated with the patient support can have an error message
displayed
thereon. In one embodiment, this error message can provide a means for a
technician to
evaluate and correct the identified fault.
In one embodiment of the present invention, upon detection of a system fault
during the
monitoring of the functionality of the patient support system, the diagnostic
and control
system can initiate a full diagnostic subsystem which can perform a more
complete
system diagnostic evaluation and, in turn, evaluate and identify one or more
sources of
the detected system fault.
In one embodiment of the present invention, the diagnostic and control system
can collect
specific information relating to the current status of particular components
of the patient
support system that are directly related to the detected fault, for example
one or more
sensor readings or the like, for subsequent use by the diagnostic subsystem
for analysis of
this fault.
Diagnostic Subsystem
The diagnostic and control system of the present invention comprises a
diagnostic
subsystem that can collect and evaluate the collected information relating to
an identified
fault and perform an analysis thereof in order to determine a source of such
fault and a
potential remedy to the detected fault. The diagnostic subsystem can indicate
malfunctions of the patient support control system which can be due to a
number of
reasons such as for example an actuator break-down, an unacceptable deviation
between
a parameter of the patient support and the patient support control system's
parameter's
desired value as, for example, caused by overload or lack of calibration of an
actuator, or
any other condition of the patient support control system. A diagnostic
program may be
applied in order to make a distinction between any critical or non-critical
function of the
patient support control system when diagnosing a malfunction.
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CA 02537601 2006-02-23
In one embodiment the diagnostic subsystem can also record a number of events
including system data and user commands into one or more log records, for
example one
or more files in an embedded or a remote controller or computer system.
Furthermore,
essential information regarding any form of treatment administered to the
supported
person can be securely recorded which could be used in the future. The log
records can
also contain information from other subsystems of the patient support.
Information in the
log records can be categorized; time stamped, and can contain human or machine-
readable data describing the event. The data can be encoded, encrypted or
clear text
messages. Each subsystem can have its own logging mechanism for logging events
specific to that subsystem, accessible only through an interface of the
subsystem or
accessible through interaction with a central controller. Events can be
categorized into
groups according to a severity or other schemes and, depending on the
categorisation,
include varying degrees of detailed information relevant to a particular
category.
In one embodiment of the present invention, the diagnostic and control system
has a
movement counting device (data logger) which is used to produce a diagnostic
that can
be used to improve the design of the system for specific uses or to perform
preventive
maintenance on the system. For example, it will be possible for an
establishment
utilising such a diagnostic and control system to use the data logger in order
to determine
the different ways in which the patient support is being manipulated and
therefore
provide information in a very constructive manner for any future designs. The
information gathered by the data logger could also used in preventive
maintenance such
that more attention is given to any parts of the patient support that is
involved in more
motion or manipulation.
In one embodiment the diagnostic subsystem can analyze the detected
information
relating to the functionality of the patient support associated with the
detected fault, and
subsequently evaluate one or more indicators that can be compared with known
indicators of known problems relating to patient support functionality. In
this manner,
based on a comparison with the indicators of known problems, the diagnostic
subsystem
can determine the specific problem. Once a specific problem has been
identified, a
possible corresponding remedy for this problem can be identified, thereby
providing a
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CA 02537601 2006-02-23
means for the remediation of the identified problem. The correlation between a
calculated indicator defined by information relating to the present status of
the patient
support system may not precisely match an indicator of a known problem. In
this
instance a probability of correlation between the evaluated indicator and the
known
indicator can be determined thereby providing a means for assigning a
confidence factor
with the identified problem.
In one embodiment of the present invention, the diagnostic subsystem can
evaluate the
identified fault through the analysis of previously detected readings, thereby
providing
for a correlation between the current readings at fault detection and previous
readings.
This manner of analysis may provide a means for identifying a malfunctioning
component, for example a sensor through the correlation with previously
detected values.
In one embodiment of the present invention, the diagnostic subsystem can be
directly
integrated into the patient support. Optionally, the diagnostic subsystem can
be
electronically coupled to the patient support upon the issuance of a error
notification.
Moreover, the patient support system architecture can comprise a diagnostic
interface
providing access to the patient support system such that a diagnostic
subsystem can be
separated or detached from the physical patient support and provide the same
set, a subset
or superset of diagnostic tools than an integrated diagnostic subsystem.
In one embodiment of the present invention, the diagnostic and control system
comprises
a communication system that can provide a means for transmitting information
relating to
the evaluated functionality of the patient support to another location. In
this embodiment,
the communication system can enable wired or wireless communication. For
example,
this form of connectivity of the patient support may enable the remote
monitoring of
patient support functionality at a location removed from the location of the
patient
support. For example, in a hospital setting, this remote monitoring can be
performed at a
nursing station or optionally can be provided at a remote location removed
from the
hospital. The communication system can enable the transmission of monitoring
and
diagnostic results to a technician for analysis, for example if a more
detailed diagnostic
analysis of the patient support is required in order to determine the source
of the indicated
CA 02537601 2006-02-23
error. This can provide a means for a detailed diagnostic to be performed and
an
appropriate remedy identified prior to the dispatching of a technician to the
patient
support site. In this manner, time may be saved as the technician may be
dispatched with
appropriate replacement parts, thereby reducing the downtime of the patient
support.
The functionality of the diagnostic and control system according to the
present invention
can be provided by any number of computing devices, for example one or more
microprocessors, one or more controllers or one or more computer systems that
can be
integrated into the patient support itself in order to provide the desired
computational
functionality. In one embodiment of the present invention, the diagnostic
subsystem can
be configured for coupling to the patient support to subsequently provide the
diagnostic
capabilities. It would be readily understood how to couple the diagnostic and
control
system to the one or more electronic elements in order to data transfer
therebetween, for
example this connection can be a wired or wireless connection.
Figure 99 illustrates an example hospital patient support having patient
support
components that can be controlled, monitored and diagnosed by one embodiment
of the
diagnostic and control system according to the present invention. The patient
support is
shown with some of its sections placed in one possible configuration. This
example of a
patient support is not to be considered limiting as the diagnostic and control
system
according to the present invention can be integrated into any number of
patient support
configurations.
Figure 80 illustrates a schematic view of one embodiment of a console or
interface that
can provide access to some or all functionality of the diagnostic and control
system,
wherein this user interface may be embedded into a patient support. The
console can be
integrated into the foot board of the patient support illustrated in Figure 99
and can
provide access to the patient support's functions. The console has back lit
zone indicators
which can indicate a set zone mode of the patient support for indicating a
preset
restriction level for movement of a supported person. Indicators can also be
multi-color
back lit to indicate an armed or disarmed state. Button can be used to set and
switch
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CA 02537601 2006-02-23
between the zone alarm as indicated by the zone alarm indicators. Button can
arm or
disarm the zone alarm functionality in a toggling fashion. Button can be
sectional or full
color or multi-color back lit to indicate an armed or disarmed state of the
zone alarm
system. Interface elements can be used to raise or lower the lying surface.
While pushing
the arrow-up button the raises and while pushing the arrow-down button the
patient
support lowers. Pushing and holding both buttons may cause the movement to
stop or
continue the movement according to the button which was pressed first. Button
can lock
out some or all functionality accessible through this or other consoles until
the button is
pressed again. Buttons and can be used to lock-out access to reorient the
respective head
and knee sections of the patient support. Button when pressed causes the
patient support
to assume a cardiac position or other predetermined shape of the patient
support surface.
Each of buttons and when pressed individually inclines or reclines the overall
support
surface without affecting the shape of the patient support surface.
Interface elements and provide button groups which when pressed can reorient
the head
or the knee sections of the and can be used in order to achieve respective
desired angles
between the upper body and the upper leg, as well as the upper leg and the
lower leg of a
patient. Display can be used to display information about certain functions or
the state of
certain parts of the patient support and its system components. Button group
can be used
to scroll through information which is available in form of a menu for display
but
exceeds the amount of information which can be displayed simultaneously on
display.
Buttons and can be used to select or enter information and to interact with
the menu
following a command and control concept.
Figure 81 illustrates an embodiment of the window content of a step in a
series of user-
patient support interaction processes that can be displayed on a detached
device such as a
general purpose computer. This is part of an interface that for example can
provide
remote access to control, diagnose, or monitor functions of the patient
support system.
The interface can provide functions to select certain components from a list
of
components or subsystems of the patient support system for detailed
investigation. The
user interface may change its look and feel by changing some or all of its
user interface
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CA 02537601 2006-02-23
components when selecting to investigate a specific component of the patient
support
system. The user interface can provide and display information in a
categorized graphical
fashion and can utilize a button status field, a motor status field, fields
for monitoring
vital information about a supported person etc.
The user interface can also provide a menu system to select from and to
provide access to
different aspects of interaction of the patient support system such as for
example, a
monitoring interface, a maintenance interface, an operator interface etc. For
example, a
maintenance interface or menu can be presented to an end user or a technician.
The
maintenance menu is able to convey very accurate information in regards to any
faulty
components in the patient support so that the end user or technician can
undertake
appropriate action. The maintenance menu can be transferred to a computer, a
server or
other external device allowing the information to be displayed to the end user
or
technician via a computer or terminal.
Therefore, remote diagnostic of the patient support can be achieved thus
improving
efficiency in remedying the fault. Switching between monitoring interface,
maintenance
interface, operator interface etc. may require authorization and may be
password or
security code protected.
Figure 82 illustrates a part of the user interface intended for use by the
supported person,
according to an embodiment of the present invention. As illustrated, the user
interface
for the supported person can provide access to reclining functions, emergency
call
functions or control of entertainment equipment.
Figure 89 illustrates a schematic diagram of the system architecture of a
patient support
control and diagnostic system. The architecture can be divided into a number
of user
interface and control subsystem components. The system architecture comprises
a power
or AC control system for supplying electrical power, an actuator subsystem
providing
ability for positioning and orienting parts of the patient support, a number
of sensor and
detector subsystems for sensing and detecting the state of parts of the
patient support, and
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CA 02537601 2006-02-23
a diagnostic subsystem as indicated. The diagnostic subsystem can interact
with the
sensor and detector subsystem or it can have its own alternative sensor and
detector
system. The user interface subsystem can comprise a number of control consoles
and
comprising indication or display systems. The display systems can have a touch
screen
or a regular display with separate buttons. The sensor system can comprise a
scale
subsystem including a load cell system. The system architecture can further
comprise a
room or other interface for communicating information to and from the patient
support
and a remote user interface system.
In one embodiment the patient support system architecture further comprises a
model
subsystem or virtual state machine for representation of the state of the
patient support
components for interaction with the controller and the user interface under
operating
conditions. Each control subsystem can comprise its own model and independent
processor or the model of the subsystem can be integrated in a central program
controlled
by a central processing unit controlling the patient support system.
In one embodiment the architecture may include a diagnostic subsystem for
monitoring
or querying the functionality or status of various patient support components.
The
diagnostic subsystem can be separate from or simply an additional component of
the one
or more control subsystems. The diagnostic subsystem can monitor some or all
of the
patient support actuators and can utilize an operatively required and already
present
sensor system or the diagnostic subsystem can have its own redundant sensor
system for
improved reliability of the patient support control system. The diagnostic
system may
monitor the patient support components on an continuous basis during the
patient
support's normal or intended operation or it may be activated only when
required to
perform certain maintenance procedures. None, some or all of the functions
intended for
use during normal operation of the patient support may be available during
some or all of
the diagnostic maintenance procedures. In addition, it may be safe for a
person to remain
in the patient support during none, some or all of the diagnostic maintenance
procedures.
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In one embodiment the diagnostic subsystem can comprise sensors for the
purpose of
self diagnosis of the patient support control system sensing the status of
actuating
components for example. Such sensors may not be required to sense the status
of the
patient support per se but rather provide access to important status
information of the
control system. Examples can include the temperature of actuator components or
controller hardware.
In one embodiment of the present invention, the diagnostic subsystem can
passively alert
users through messaging systems, for example error messages displayed on the
display
system. The diagnostic subsystem may also provide procedures to actively query
internal
status information of the patient support system not intended for use during
normal
operation. Examples of internal status information can include any kind of
readings from
sensors or results from self diagnostic modes of employed digital devices.
This
information can be important, for example, when calibrating actuators and
their
respective motion sensor system to accurately scale sensor readings to provide
positioning information that corresponds with the true physical position of
the respective
patient support component. Other examples for internal status information
include power
supply voltages or current readings.
In one embodiment the diagnostic subsystem can also include a debug mode
permitting
the step-by-step execution of commands or procedures of the microcontroller or
processing unit. For example, the diagnostic subsystem could be accessed via a
general
purpose computer for extensive debugging of such subsystem.
In one embodiment of the present invention, the diagnostic subsystem has a
simple
graphic interface that gives a code to the user to diagnose the problem with
the faulty
component. The user then cross-references with another document or program to
interpret
the code to diagnose the problem.
In another embodiment, the diagnostic subsystem has a complete graphical
interface that
communicates in plain language to the user who has to interpret the problem
with the
faulty component
CA 02537601 2006-02-23
The diagnostic subsystem in both embodiments can also be coupled to a remote
location
via a network connection which is either wired or wireless. The remote
location in one
embodiment is the factory that can identify the cause of the fault and send a
technician
with the parts and advanced knowledge of the fault to minimize the downtime of
the
faulty component
In another embodiment, the diagnostic subsystem is used to perform preventive
maintenance on the patient support. Since the motherboard on the control
susbsystem
can record and interpret data, it can send signal to prevent failure of a
component before
it happens.
The communication between different components within the patient support
control and
diagnostic system is achieved through network communication between components
such
as CAN-Open for example. This protocol utilizes the broadcast of information
to the
different electronic components (or module) within the patient support.
Information
regarding any commands requested by the end user is thus transferred to every
single
electronic component within the patient support and thereafter, action is
taken by the
component (or module) which is concerned by the information that has just been
broadcast. Alternatively, the communication between different components
within the
patient support control and diagnostic system can be achieved by a peer-to-
peer network
communication system or any other network communication protocol that would be
known to a worker skilled in the art.
Figure 90 illustrates an embodiment of a load cell system 251 that is used for
monitoring
movement of a patient. The system can be integrated into the patient support
or can be
part of a person support element such as a lying surface 20. In addition, the
load cell
system 251 can comprise a number of load cells or load sensors for example a
load cell
which can be embedded in the patient support proximally positioned at each of
a patient's
limbs and optionally at the center of the patient support. The load cell
system also can be
comprised of a mesh of load cells for example. The signals from the load cells
can be
monitored and processed by a processing unit in the load cell system or a
central
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processing unit capable of monitoring, processing, and controlling signals
from the
patient support's subsystems. Instead of forming part of a support element
such as a
lying surface the load cell system can also integrated into the surface of the
patient
support for supporting the support element. The load cell system 251 can
provide a
measure for the pressure, weight, or mass load of a certain load cell, for
example foot left
or right load cell values and head left or right load cell values and
additional information
about the location of the center of gravity.
In one embodiment the control and diagnostic system 1400 can comprise an
additional
scale subsystem providing a calibration process for calibrating the scale
subsystem to
provide accurate reading of a patient's weight and subsequently to calibrate a
motion
detection system for monitoring movement of the patient. It may be necessary
to
calibrate the load cells' 250 electronics in order to provide match the sensor
signals with
the scale subsystem electronics.
In one embodiment, the tilt sensors 260 can be used with a control and
diagnostic system
1400 as a means for fault detection. For example, where no change in an angle
is
detected when an actuator is being activated to modify said angle, the
situation can be
indicative of a blockage related to the actuator movement or an actuator
malfunction
Figures 96 schematically illustrates an embodiment of the motor control
subsystem with a
number of attached actuators and limit switches. It is understood that,
depending on the
functionality of the patient support, there can be different numbers of
actuators or limit
switches than illustrated. In this embodiment the surface of the patient
support can be
shaped by orienting a head, thigh, and a foot section where the support
surface for a
supported person is intended to fold and provide an adjustable angle between
the upper
body and the thigh as well as under the knee between the thigh and the lower
leg. The
head actuator can position the end of the head section, and the thigh actuator
can position
the knee section of the lying surface support relative to an even support
structure. The
HI-LO head actuator can position the head end of the even support structure
relative to
the frame of the patient support, which is in contact with the floor. The HI-
LO foot
actuator can position the foot end of the even support structure relative to
the frame of the
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patient support, for example. The two HI-LO actuators and can pivot the
support surface
horizontally whereas the head and the thigh actuator can shape the support
surface by
pivotally adjusting sections of the lying surface support.
In one embodiment, the motor control subsystem is connected to a number of
limit switch
or angle sensor systems which ensures that the actuators do not move or
position parts
beyond predetermined limit angles or distances. When a part or section of the
patient
support reaches a predetermined limit position while moving, the motor control
subsystem can receive a status change signal via one or more limit sensor
signals and can
interrupt the respective movement. The motor control subsystem can have a
safety
control feature that does not allow any further continued movement in that
same direction
or orientation unless the limit condition indicated by the limit sensor system
is resolved.
Provided that no movement of other degrees of freedom of the patient support
takes place
the limit condition typically can be resolved by reversing the original
movement.
As discussed previously, each component of the motor control system including
the
actuators and the limit switch sensor system can provide diagnostic features
or a
diagnostic mode. The diagnostic features also can include a separate redundant
diagnosis
sensor subsystem for monitoring the state of the respective device or
component for
example a temperature sensor or a redundant parallel or serial sensor limit
switch system
to enhance the reliability of the positioning system. An important aspect of
the
diagnostic subsystem that is relevant to the motor control system can regard
the accurate
calibration of sensors providing actuator position information. The motor
control system
interprets actuator position sensor signals to be accurate representations,
encoded in form
of a suitable signal, of the real position of a respective part or section of
the patient
support. The motor control system may fail to execute a given command when the
real
position deviates from the motor control system's perceived position as
provided by or
derived from an actuator signal. In such a case the diagnostic system can
provide
functionality to help avoid or diagnose a malfunction which can reach from
functionalities such as automatic recalibration to alerting or messaging.
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Figure 97 schematically illustrates an embodiment of the user interface
controller with a
number of attached user interface consoles. The patient support can have a
number of
user-interface consoles each providing access to a certain set of patient
support system
functions. For example the patient support can have user interface consoles
integrated
into one or both of the side rails of the patient support providing easy
access to certain
patient support system functions to a supported person or a person at the side
of the
patient support.
The patient support can also have a user interface console located at the foot
or the head
section of the patient support. Each such interface console may be integrated
into a
respective foot or head board of the patient support for example. A foot or a
head
interface console may provide access to a set of patient support system
functions different
from each other as well as different from the side rail consoles. There can be
inner or
outer side rail consoles intended for access from within or from outside of
the patient
support. An embodiment of a side rail interface console is illustrated in
Figure 82 and an
embodiment of a foot board interface console is illustrated in Figure 80. The
foot board
console can have a display system included. The display system can be a touch
screen
display or a simple passive display system with a separate input system as
illustrated in
Figure 2. In addition the interface controller can have a remote control
interface to which
a remote console can be connected. The remote control interface can provide
wired or
wireless connection to a specialized or a general purpose computing device for
example.
A number of different bus systems and control protocols are available to
communicate
through the remote control interface as discussed previously and as would be
known to a
person skilled in the art. The interface controller may also provide a number
of
additional control or remote control interfaces.
In one embodiment the interface controller as well as the attached user
interface consoles
can have self diagnosis features or provide an interface for access to
diagnostic
procedures. The interface controller may be able to provide a debugging mode
for step-
by-step execution of control commands or to query status information of the
components
or devices of the patient support system.
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Figure 98 illustrates a part of a scale subsystem according to one embodiment
of the
present invention. The scale subsystem can connect to a number of load
sensors. The
number of load sensors can be different from the ones illustrated. In this
embodiment
four load sensors which are capable of sensing pressure and can be calibrated
to provide a
measure of force or weight applied to each sensor are attached to the scale
subsystem
control interface. The scale subsystem controller can process signals incoming
from the
load cells and can be used to detect the status of a supported person. The
scale control
subsystem can be configured to provide a messaging signal or to alert
monitoring
personnel through an external alarm system interface for example. If each load
cell is
properly calibrated, the scale control subsystem can also provide a measure of
the weight
of a supported person. The information can be utilized to determine a person's
mass or
weight or the respective mass or weight and can also be used to record this
information in
another subsystem of the patient support that may be desired for patient
monitoring for
example.
In one embodiment, the scale subsystem may require occasional calibration
depending on
the nature of the chosen sensor technology. Access to the scale subsystem for
calibration,
monitoring or diagnostic purposes may be possible through the user interface
as
described in Figure 97.
It is understood that any kind of diagnostic procedure also includes
inspection of the
corresponding component and that each component may provide a hardware
interface for
connection to a special purpose diagnostic device for diagnosing the
component.
EXAMPLES
Some examples of how the communication system is used to interface with the
patient
support are provided.
Main Power Switch
The patient support is equipped with a main power switch located at the head
end of the
patient support. This power switch must be switched on in order to activate
the patient
support functions. Should this switch be turned off, or there is other
interruption to the
CA 02537601 2006-02-23
power, such as a power failure, the settings of the lockout controls and the
calibration
data of the Scale and the Patient Support Exit systems are preserved.
Brake/Steer Foot Pedal Control
The patient support is equipped with two lateral pedals secured to the middle
section of
the base frame member. The pedals control the brakes and the centrally-located
drive
wheel 760. The functions of the pedals are determined by the user pushing in a
forward
or backward motion; such forward or backward motion corresponding to either
brake
control or steering control as denoted by affixed labels. Neutral control is
maintained by
leaving the position of the brake in the middle.
The patient support is equipped with a central locking system engaged by
either lateral
brake/steer pedals. The system is toggled by fully depressing the pedal in the
direction
indicated by the affixed labels.
The patient support is equipped with a drive wheel 760 and is engaged by fully
depressing the brake/steer pedal in the direction indicated by the affixed
labels. The
drive wheel 760 is centrally located under the base frame member and aids in
guiding the
patient support along a straight line and around corners.
Foley Bag Hook
Four Foley bag hooks are located on both sides of the patient support under
the edges of
the lying surface support head and seat sections. The Foley bag hooks move
when the
fowler is raised or lowered. The fowler motion is intended to be locked out
when the
Foley bag hooks are in use.
Patient Strap Locations
There are 12 locations on the lying surface support for installing patient
restraint straps.
Ten are located on the long edges of lying surface support directly across
from each
other. The other two are located along the head edge of the lying surface
support.
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Night Light
The patient support is equipped with an optional photoelectric night light to
illuminate
the floor area around the patient support. The light turns on as the ambient
light dims.
CPR Emergency Release
The CPR emergency release system includes two handles located either side of
the head
section of the patient support. Pulling on either of the CPR emergency release
handles
will flatten the fowler and knee gatch, should either be raised. The handles
can be
disengaged at any time before the fowler or knee gatch have completely
lowered. The
fowler must be lowered completely by pulling on the CPR emergency release
handles or
the fowler down control in order to reset the fowler motor.
Nurse Call Usage System
The nurse call usage system includes a speakerphone and a nurse call button,
both of
which are integrated to the inner control panel of the head siderails. The
communication
between patient and nurse is established when (a) a patient presses the nurse
call button;
or (b) when the power to the nurse call usage system is interrupted.
Auxiliary Power Outlet Usage System
The patient support contains an auxiliary power outlet located at the foot end
of the
patient support. The outlet is integrated to a 5 Amp breaker.
Manual Siderail Control System
There are two sets of siderails located on either side of the patient support.
The first set is
located at the head end and the second is located at the foot end. The
siderails may be
raised to prevent a patient from inadvertently rolling off the patient
support, or lowered to
allow a patient to exit the patient support. A lever is attached to the lower
portion of each
siderail. Engaging said lever allows the siderail to raise or lower with the
use of one
hand. In the lowered position, the siderail may be pushed into the lying
surface support.
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Head and Foot Board System
The patient support includes a head board and a foot board, located at the
head end of the
patient support and the foot end of the patient support, respectively. Both
head board and
foot board can be removed by lifting the board out of mounting sockets that
are located
on the lying surface support. The foot board mounting socket contains an
electrical
socket for delivering power and information to the control panel located on
the foot
board. Removing the foot board will trigger a lockout of the system. The
lockout can be
deactivated where siderails have a control panel located on them.
Foot Board Control Panel System
The foot board contains a control panel system that controls the electrical
functions of the
patient support. The control panel is located on the outside of the foot
panel, facing away
from the patient support. The control panel contains the following functions:
raise/lower
fowler, raise/lower knee gatch, raise/lower patient support in Trendelenburg
position
(lying surface flat in an inclined position with head either above or below
feet), cardiac
chair position control, lockout controls for fowler and knee gatch, total
lockout button,
raise/lower patient support, Scale Control System controls, and Patient
support Exit
Control System controls.
Foot Board Controls: Scale System and Scale System Controls
The patient support optionally includes a scale system. The control functions
are located
on the foot board control panel. The scale system includes software, which can
be of
varying software versions. The scale system includes a power button that
activates or
deactivates the scale system separately from other electrical functions of the
patient
support. The scale system includes a zero function, which returns the scale
measurement
to zero when there is no patient occupying the patient support. The scale
system includes
several information and information tracking options. These include options
for viewing
current weight, viewing gain or loss in weight, viewing the reference weight
used to
measure gain or loss of weight, setting for changing equipment, changing
patient weight,
selecting unit weight. The scale system display will turn off automatically
after one
minute of idle time. The scale system remains active at all times except when
the change
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equipment function is triggered. The scale will not operate if the angle of
the patient
support surpasses 12 degrees when in the Trendelenberg position. The scale
equipment
may be added or removed while the patient is in the patient support by
selecting the
change equipment option. The same weight that was displayed prior to changing
equipment will display when the equipment is replaced.
Foot Board Controls: Patient support Exit Detection System
The patient support can optionally include a patient support exit detection
system. The
patient support exit control system includes a display panel that is located
on the foot
board control panel. The control panel includes an arming/disarming function
button and
display light that is activated when the patient support exit system is armed.
The
Arm/Disarm button arms or disarms the system. The scale system must be zeroed
prior
to arming the patient support exit detection system. The scale system triggers
the patient
support exit detection system when the system is armed and a patient exits the
patient
support. Upon the system being triggered, an alarm in the patient support will
sound. If
the patient support is equipped with a nurse call button, the alarm will sound
at the nurse
call station.
Foot Board Controls: Zone Control System
The patient support optionally includes a zone control system, which may
replace the
patient support exit system. The zone control system includes a display panel
that is
located on the foot board control panel. The control panel includes an
arming/disarming
function button, a zone control button, and display lights that correspond to
a desired
zone of detection. The Arm/Disarm button arms or disarms the system. The scale
system must be zeroed prior to arming the zone control system. The zone
control system
has different levels of detection sensitivity, each of which can be selected
by pressing the
zone control button. When the first zone is selected, a patient can move
freely in the
patient support without triggering the zone control system; the system is
triggered when a
patient leaves the patient support. When the second zone is selected, a
patient can make
some movements, such as sitting up or rolling over, without triggering the
zone control
system; the zone control system is triggered when the patient attempts to exit
the patient
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support. When the third zone is selected, any small movement by the patient
triggers the
zone control system. An alarm will sound at the patient support when zone
control
system is triggered. If the patient support is equipped with a nurse call
button, the alarm
will sound at the nurse call station.
Head Siderail Control Panel System
The siderails can optionally contain control panels for the electrical
functions of the
patient support. The control panels can be located on the inside or outside of
the head
siderail. The control panels on the inside and the outside of the siderails
include the
following functions: raise fowler (or head end of lying surface support),
lower fowler,
raise knee gatch, lower knee gatch, raise patient support, lower patient
support. The
control panels on the inside of the siderails can include the following
additional
functions: nurse call and optional communications package (includes controls
for room
lighting, reading light, and power and volume buttons for external television
and radio
systems).
Accessories System
The patient support can optionally include various accessories. These
accessories
include:
~ patient support extension;
~ oxygen bottle upright holder;
~ monitor tray;
~ 2-stage folding fixed intravenous pole;
~ 3-stage folding fixed intravenous pole;
~ removable anodized aluminum intravenous pole;
~ emergency crank;
~ padded siderail covers; and
~ two-function Curbell pendant control.
The disclosure of all patents, publications, including published patent
applications, and
database entries referenced in this specification are specifically
incorporated by reference
CA 02537601 2006-02-23
in their entirety to the same extent as if each such individual patent,
publication, and
database entry were specifically and individually indicated to be incorporated
by
reference. These publications include the Parts List (January 2006), the
Operations
Manual (December 2005), and the Maintenance Manual (December 2005) for the
Model
FL28EX, obtainable from Stryker Corporation, MI.
It is obvious that the foregoing embodiments of the invention are exemplary
and can be
varied in many ways. Such present or future variations are not to be regarded
as a
departure from the spirit and scope of the invention, and all such
modifications, as would
be obvious in the art, are intended to be included within the scope of the
following
claims.
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