Note: Descriptions are shown in the official language in which they were submitted.
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"A Therapeutic Bed"
Background of the Invention
This invention relates to a therapeutic bed, and in
particular to prone positioning beds.
Patient positioning has been used for some time as a
treatment for patient comfort, to prevent skin breakdown,
improve drainage and to facilitate breathing. One of the
goals of patient positioning has been maximisation of
ventilation to improve systematic oxygenation. Various
studies have demonstrated the beneficial effects of body
positioning and mobilisation on impaired oxygen transport.
The support of patients in a prone position can be
advantageous in enhancing extension and ventilation of the
dorsal aspect of the lungs.
The present invention particularly relates to therapeutic
beds. of the type comprising a base frame, a patient
support platform rotatably mounted on the base frame for
rotational movement about a longitudinal rotational axis
of the patient support platform, and drive means for
rotation of the patient support platform on the base
frame.
In our previously filed patent application, publication
no. WO 97\22323, we described a therapeutic bed of this
type for supporting a patient in either a supine position
or a prone position and for using kirietic therapy.
This type of bed is particularly suited for the treatment
of patients with respiratory problems. The beds
advantageously allov,r rotation of the patient on the
patient support platform and, where required, rotation of
the patient support platform into a prone support position
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which is particularly desirable in the treatment of
patients with severe respiratory problems.
In such therapy, a patient may be heavily intubated with a
number of tubes extending over a sicie of the bed between
the patient on the bed and associated apparatus mounted on
stands or the like alongside the bed for either delivering
liquids to the patient or draining liquids from. the
patient. Also, there may be a number of wires extending
from sensors on the patient to various monitors adjacent
the bed. These ventilation and drainage tubes, medication
supply tubes, monitoring cables and the like are
collectively called patient care lines throughout this
patent specification. The term "patient care lines" as
used in this patent specification is taken to mean any
tubes, pipes, conduits, cables and the like lines for
delivery or drainage of fluids to or from a patient, for
monitoring a patient's condition ar.Ld generally speaking
for treating a patient on the patient support platform of
the bed. These patient care lines present a problem,
particul'arly when rotating the patient support platform
between a supine support position and a prone support
position, in that they can easily become entangled and may
be inadvertently pulled away from the patient. To avoid
this a nurse or other attendant haz; to carefully handle
and adjust the patient care lines as necessary whilst the
bed is rotating. This can be extreinely awkward. Access
to the patient and the patient care lines is difficult
when the patient support platform is at or approaching the
prone support position.
ti
Another problem that arises is in ensuring that the
patient is correctly secured to the patient support
platform before rotating the patient support platform. away
from a horizontal supine support position. Again, a nurse
has to check all the patient retaining strapping, rails
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and supports are secure prior to rotation of the patient
support platform into the prone support position. This
tends to be very time consuming. Also, it is not always
easy to check the strapping or other restraints are
correctly and securely engaged.
To rotate the patient support platform between the supine
support position and the prone support position, typiLcally
a number of nursing staff are required to rotate the
patient support platform and at the same time, handle the
tubing and wiring to prevent entanglement or dislodgement.
Thus, a number of nursing staff'may be diverted from other
duties for a considerable time. Consequently, the
operational efficiency is adversely effected and costs
increased for the hospital.
The present invention is directed towards overcoming these
problems.
Summary of the Invention
The invention is characterised in that there is provided
guide means for patient care lines at one or both ends of
the patient support platform for guiding the patient care
lines between a patient on the patient support platform
and associated apparatus externally of the patient support
platform, said guide means being mounted at or adjacent
the longitudinal rotational axis of the patient support
platform.
Advantageously, the invention provides a bed incorporating
a patient care line management system for optimum handling
of patient care lines particularly when rotating the bed
between a supine support position and a prone support
position. The risk of entanglement or dislodgement of the
patient care lines is minimised as the lines are securely
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supported by the guide means during rotation of the
patient support platform.
In a second aspect, the invention is characterised in that
there is provided a retaining means for releasably
securing a patient on the patient support platform, the
retaining means being operatively connected to the drive
means for rotation of the patient support platform to
regulate rotation of the patient. support platform in
response to correct engagement of the retaining means.
This construction advantageously prevents rotation of the
patient support platform unless the patient is securely
strapped or otherwise restrainedon the patient support
platform. Also, it gives a simple and quick indication to
nursing staff as to whether or not the patient is properly
secured on the patient support platform.
In a third aspect, the invention is characterised in that
there is provided drive means which is operable for
rotation of the patient support platform on the base
frame, means for sensing the orientation of the patient
support platform on the base frame, and means for
controlling operation of the drive means in resporise to
the sensed position of the patient support platform on the
base frame. In this way, the rotation of the patient
support platform can be readily controlled in a simple
manner to rotate the patient support platform between a
number of desirable orientations on the base frame. Also,
the base support platform can be controlled to move
between different orientations leaving a nurse fr.ee to
attend to the patient if necessary while this is being
carried out.
In one embodiment, means is provided for securing the
patient care lines on the guide means.
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In another embodiment, the guide means comprises a tubular
guide for through passage of the patient care line or
lines.
In a further embodiment, the tubular guide has a bore for
through passage of the patient care lines and a bore
insert is provided for engagement within the bore, the
bore insert having a number of spaced-apart slots about a
periphery of the insert, each slot for receipt of a
patient care line, each slot being closed by a side wall
of the bore when the insert is mounted within the bore.
In another embodiment, the guide means comprises a guide
body having a number of patient care line receiving slots
for reception of the patient care lines.
In a further embodiment, the guide means has a guide body
with a number of spaced-apart peripheral slots for
reception of patient care lines.
Preferably, each slot has a side opening=, and closure
means is engagable across the side opening to releasably
retain a line within the slot.
In another embodiment, the closure means is aspring-
loaded finger normally biased into a slot closing position
across the side opening and retractable against spring
bias for insertion and removal of a. line into or from the
slot.
Preferably, the closure means is a quick-release strip
engagable across the side opening.
In a further embodiment, the guide body is movably mounted
on the patient support platform for vertical movement of
the guide body on the patient support platform.
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Preferably, the guide body is slidably mounted on the
patient support platform.
In another embodiment of the invention, there is provided
retaining means for releasably securing a patient on the
patient support platform,
said retaining means being opE:ratively connected to
the drive means to regulate rcitation of the patient
support platform in response to correct engagement of
the retaining means.
In a further embodiment, the retaining means comprises a
number of pairs of support elements mounted between a head
end and a foot end of the patient support platform,
each pair of support elements comprising associated
support elements mounted on opposite sides of the
patient support platform and having a fastener to
secure the support elements together to retain a
patient on the patient support platform,
sensing means associated with each fastener to sense
correct engagement of the fastener,
said sensing means being connected to a contr.oller
for controlling operation of the drive means.
In another embodiment, each fastener has a complementary
pair of fastener parts, namely a first fastener part and
a second fastener part,
one fastener part being mounted on each of the pair
of support elements,
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the first fastener part being normally biased out of
engagement with the second fastener part,
the first fastener part co-operating with the sensor
when in an engaged position to indicate that the
fastener parts are engaged.
In a further embodiment, the sensor has a magnetically
operated switch and an operating magnet is mounted on
the first fastener part to operate the switch.
In another embodiment, the support elements are mounted
on side rails upstanding at each side of the patient
support platform.
Preferably, each side rail is removably mounted on the
patient support platform having ineans for releasably
engaging the patient support platforn-,
locking means to secure the rail on the patient
support platform,
rail sensing means to sense interlocking engagement
of the rail with the patient support platform,
said rail sensing means being operatively conriected
to the controller for the drive means such that the
drive means will only operate if the rail is
correctly engaged with the patient support platform.
In another embodiment, means is provided to lock each
rail on the patient support platform when the patient
support platform is in an inverted position.
In a further embodiment, one or more hinged panels are
provided in the patient support platform to provide access
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to a patient when the patient support platform is in an
inverted position,
each panel having panel locking means to secuire the
panel in a closed position ozi the patient support
platform,
panel sensing means being provided to sense locking
engagement of .the panel with the patient support
platform,
said panel sensing means being operatively connected
to the controller for the drive means such that the
drive means will only operate if the panel is locked
in a closed position on the patient support platform.
In another embodiment, there is provided means for
sensing the orientation of the patient support platform
on the base frame, and means for controlling operation
of the drive means in response to t:he sensed position of
the patient support platform on the base frame_
In a further embodiment, the sensing means comprises a
ring mounted on the patient support platform co-axially
with the rotational .axis of the patient support
platform,
the ring having a first series of slots spaced at 1
intervals about the ring,
the ring having a number of sets of location slots
;spaced-apart about the ring, each set of location
slots giving an indicatiori of a particular
orientation of the patient support platform relative
to the base frame,
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and a complementary position reader associated with the
disc, the position reader being mounted on the base
frame and having complementary light emitter and
receiver pairs supported at opposite sides of the disc
for cooperation with the slots in the disc to determine
the orientation of the patient support platform on the
base frame.
In another embodiment, the ring has a number of parking slots
located about the ring defining a number of parking locations
for the patient support platform on the base frame at which
a locking bolt is engageable between the patient support
platform and the base frame to lock the patient support
platform on the base frame.
In a broad aspect, then, the present invention relates to a
therapeutic bed comprising: a base frame, a patient support
platform rotatably mounted on the base frame for rotational
movement about a longitudinal rotational axis of the patient
support platform, a motor operable to rotate the patient
support platform on the base frame, and a guide body defining
one or more patient care line receiving slots operable to
guide one or more patient care lines from an apparatus
external of the patient support platform to a patient on the
patient support platform.
Brief Description of the Drawings
The invention will be more clearly understood by the
following description of some embodiments thereof, given by
way of example only, with reference to the accompanying
drawings, in which:
Fig. 1 is a perspective view of a therapeutic bed
according to the invention;
Fig. 2 is another perspective view of the therapeutic
bed, shown in another position of use;
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Fig. 3 is a further perspective view of the bed with a
patient support platform of the bed shown in an inverted
prone patient supporting position;
Fig. 4 is an end elevational view of the bed;
Fig. 5 is a perspective view of a frame of the
therapeutic bed;
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Fig. 6 is a perspective view of a base portion of the
bed frame with a patient support platform of the bed
removed;
Fig. 7 is an elevational view of: a frame of the bed;
Fig. 8 is a plan view of the bed frame shown in Fig.
7;
Fig. 9 is a plan view similar to Fig. 8 showing
hinged panels of the patient support platform in
place on the bed frame;
Fig. 10 is a perspective view of the bed in use and
supporting a patient in a supine: position;
Fig. 11 is a perspective view of the bed in use,
supporting a patient in a prone position;
Fig. 12 is a detail exploded sectional view of a side
rail locking mechanism for the bed;
Fig. 13 is a detail sectional elevational view of a
side rail locking mechanism for the bed shown in
another position of use;
Fig. 14 is a sectional elevational view of a panel
locking mechanism on the patient support platforni;
Fig. 15 is an enlarged detail sectional view of
portion of the locking mechanism of Fig. 14;
Fig. 16 is a view similar to Fig. 15 showing the
locking mechanism in another position of use;
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Fig. 17a is a detail perspective view of patient
retaining flaps of the bed;
Fig. 17b is a circuit diagram for a rotational
interlock incorporated in the flaps;
.Fig. 17c is a detail perspective view of a patient
retaining strap and buckle for securing the flaps;
Fig. 18 is an elevational view showing a tube guide
at one end of the bed;
Fig. 19 is a detail elevational view of a rotary
encoder ring forming portion of a rotational control
mechanism for the patient support platform of the
bed;
Fig. 20 is a detail side elevational view of a rotary
encoder forming portion of the bed; and
Fig. 21 is a detail view showing pbrtion of the
rotary encoder ring.
Detailed Description of the Invention
Referring to the drawings there is illustrated a
therapeutic bed according to the invention indicated
generally by the reference numeral I. The bed 1 comprises
a ground engaging chassis 2 mounteci on wheels 3. A base
frame 4 is secured on the chassis 2 by pivot linkages 5.
Rams 6 housed within the base frame 4 operate the pivot
linkages 5 to raise and lower the base frame 4 on the
chassis 2. The rams 6 may be opeii-ated to keep the base
frame 4 level as it moves or may be operated to raise or
lower one of the ends of the base frame 4 to tilt the base
frame 4 about a transverse axis of the base frame 4 to
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move a patient support platform 7 carried on the base
frame 4 into a Trendelenburg position. The patient
support platform 7 is rotatably mour.Eted on the base frame
4 for rotation about a longitudinal rotational axis of the
patient support platform 7 between a supine si.ipport
position shown in Fig. 1 and a prone support position
shown in Fig. 3.
The patient support platform 7 has a pair of upright end
rings 8,9 each of which sits on and rotatably engages an
associated pair of spaced-apart rollers 10 (Fig. 6) at
.each end of the base frame 4. Side support bars 12,13
extend between the end rings 8,9. A. central cross bar 14
extends between the side support bars 12,13. Hinged
panels 16,17 (Fig. 9) are hingedly connected to the cross
bar 14 and can be opened when the bed 1 is in the prone
position as illustrated in Fig. 3 for access to the back
of a patient on the bed 1. It will be noted that this
construction gives good access to the: patient with minimal
obstruction.
A slap shut mechanism 20 (Figs. 9 and. 14 to 16).. is mounted
on each panel 16,17 for engagement with the support bars
12,13 to securely lock the panels 16,17 in the closed
position. A spring loaded locking pin 22 is slidably
mounted within an elongate tubular housing 23 for movement
between a retracted stored position (Fig. 15) and an
extended position (Fig. 16) in which the locking pin 22
engages in an associated receiver slot 23a in the support
bars 12,13. Sensors (not shown) detect correct locking
engagement of each locking pin 22 with its associated
receiver slot 23a and sends a signal to a rotational
controller for the patient support platform 7 which
prevents rotation of the patient support platform 7 unless
both panels 16, 17 are securely locked on, the patient
support platform 7. A gravity pin 21 is slidable under
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gravity in an associated tube 21a on the housing 23 side
wall for engagement with a complementary circumferential
groove 24 in the locking bolt 22 when the patient Isupport
platform 7 is in the supine position to prevent opening of
the panels 16, 17, the gravity pin 21 sliding out of
engagement with the groove 24 when the patient support
platform is in the prone position to allow opening of the
panels 16, 17. A handle 98 is prov:ided at an inner end of
the locking pin 22 for manual release of. the locking pin
22 which can be retracted against spring 99 within the
housing 23. Thus, the panels 16, 17 are released for
opening. In the retracted position, Figs. 14, 15, a
spring loaded catch 100 mounted on the locking pin 22
engages a slot 101 in a side wall of the housing 23 to
retain the locking pin 22 in the retracted position. The
catch 100 can be pressed into the housing 23 against
spring 105 bias to release the locking pin 22 which is
then urged outwardly by spring 99 into the outwardly
extending engagement position shoFm in Fig. 16 for re-
locking the panels 16, 17 on the patient support platform
7.
At each side of the patient support platforin 7 upstanding
side rails 25 are provided. Eat:h side rail 25 has a
downwardly extending stanchion 26 at each end which is
engagable with a complementary socket 27 (see Fig. 13) in
one of the support bars 12,13 of the patient support
platform 7. Upon engagement of the stanchion 26 with the
socket 27 a spring loaded locking pin 28 housed within the
bar 12,13 is engagable through an opening 24 in the side
wall of the socket 27 with a locking slot 29 in the
stanchion 26. A handle 30 at an inner end of the locking
pin 28 is operable to slide the locking pin 2-8 in an
associated housing31 housed within the bar 12, 13 for
release of the stanchion 26. A spring 31a within the
housing 31 urges the locking pin 28 outwardly of the
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14
housing 31 into a stanchion engaging position. It will be
noted that an associated gravity operated retaining pin 32
is slidably mounted in a tubular casing 33 on the housing
31 such that when the patient support platform 7 is in the
inverted prone position the pin 32 drops downwardly under
gravity (in the direction of arrow A, Fig. 13) to prevent
retraction of the pin 28 locking the rails 25 in position.
A sensor 35 is engagable with each pin 28 to determine
the position of the pin 28 to register if the pin 28 is
engaged or disengaged with the stanchion 26. All of the
sensors 35 are connected in series and are connected to a
rotational controller for a motor which rotates the
patient support platform 7 such that the motor will not
operate until all the sensors 35 indicate that the pins 28
are properly engaged with the stanc.hions 26 so that the
rails 25 are securely attached to and locked in position
on the patient support platform 7.
To retain a patient on the pati.ent. support platform 7,
associated pairs of patient support flaps 40,41 (Fig. 1)
are pivotally mounted on opposite sicie rails 25 and can be
secured together by locking straps 43 to securely retain a
patient on the patient support platform 7 as described in
our previous patent application Publication No. W097/22323
(the details of which are incorporated herein by
reference). Each strap 43 comprises a web 44 with either
a buckle 45 (Fig. 17) or associated clip 46 at a free end
of the web 44, the buckle 45 and clip 46 forming a quick
release fastener. The web 44 when the buckle 45 is
released is shortened by an elastic band 47, which is sewn
in a stretched position onto one side of the web 44, to
withdraw the buckle 45 from'over a magnetically operated
switch 48 mounted on the associated flap 41 on which the
buckle 45 is mounted. The magnetic switch 48 is mounted
inside each flap 41 and immediately below the magnet in
the tightened buckle 45. A series circuit of the magnetic
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switch 48 and a resistor 49 terminates in a connector 49a
which is accessible on an exterior of the flap 41. By
choosing a unique value of resistor for each flap 41 and
measuring it, correct closure of each buckle 45 can be
validated. Thus, when the buckle 45, which incorporates a
small magnet, is in the engaged position the magnetically
operated switch 48 is operable to confirm that the buckles
45 and clips 46 are correctly joined and the patient is
thus correctly secured on the patierit support platform 7.
Each of the fasteners must be correctly engaged before the
patient support platform 7 can be rotated.
A hand-held controller 85 (Fig. 4) is mounted in a pocket
86 at the foot of the bed 1. This controller 85 has a
contact for engagement with the connector 49a to allow the
controller 85 to check the buckle 45 is properly engaged
(the switch 48 is closed) and determine the value of the
resistance 48 to identify the flaps 40, 41 being checked.
Each of the flap pairs 40, 41 are checked in sequence
starting at the foot of the bed and moving towards the
head end of the bed. Preferably, the patient support
platform 7 will not be released for rotation unleszc flap
locking is confirmed in the correct sequence and the
sequence is complete. This ensures all the flaps are
checked together at the same time.
Assuming all the interlocks are clear, the hand-held
controller 85 can be used to remotely send an operating
signal to the rotation motor controller to rotate the
patient support platform 7. A nurse can move arourid the
bed 1 as the patient support platform 7 rotates,
controlling rotation with the controller 85 to ensure
there are no problems with the patient or the_patient care
lines during rotatiori.
Management means for patient care lines such as tubes and
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sensor cables is provided on the bed. At a foot end of
the bed the management means comprises a central opening
50 (Fig. 5) adjacent a longitudinal axis of the patient
support platform 7 for supporting and through passage of
the patient care lines. A care line holder 57 (Fig. 4) is
removably engagable within the opening 50 and has a number
of spaced-apart circumferential slots 58 each for
reception of a patient care line. Each slot 58 is closed
by the side wall of the opening 50.
At a head end of the bed the patient care line management
means comprises a guide body 51 (Figs. 1 and 18) mounted
adjacent the longitudinal axis of the patient support
platform 7 and slidable on associated rails 52 so that it
drops beneath the head of the patient when the. bed. is in
either the supine or the prone pos:ition. The guide 51 has
a number of slots 54 for reception of patient care lines.
The slots 54 may be of different sizes as shown to
accommodate different lines. When the patient care lines
are engaged with the slots 54, a spring loaded retaining
finger 55 mounted across the inlets of each s:Lot 54
retains the patient care line within the slot 54. The
guide body 51 is mounted on a rod 56 which is rotatably
mounted on sliders 59 which slidably engage the rails 52.
Thus, the guide body 51 can be rotated out of the way for
better access to a patient's head if necessary. It will
be appreciated that this patient care line management by
leading the patient care lines axially outwardly at each
end of the bed greatly facilitates handling of the patient
care lines when moving the patient support platform
between the supine and prone support positions. Also, the
patient care lines are securely held to prevent
inadvertent withdrawa.l from a patient.
A drive for the patient support platform can be of the
type described in our Patent Specification No. W097/22323
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(the details of which are incorporated by reference),
essentially comprising a belt drive between the patient
support platform 7 and an associated electric motor on the
base frame 4 at a foot end of the bed 1. In this case
however operation of the motor is controlled by a rotary
opto encoder comprising a code disc 60 with three
concentric tracks of slots 61, 62, 63, see Figs. 19 to 21
and a complementary position reader 64. An outer angle
track 61 comprises slots at 1 intervals. An intermediate:
track 62 has slots to provide index identification and an
inner index track 63 has slots in l:ine with the loc]?; ring
park position. The disc 60 is attached to the patient
support platform 7 and the associated position readler 64
is mounted on the base frame 4. The position reader 64
has a channel 64a for reception and through passage of an
outer portion of the disc 60. Light emitters 65 are
mounted at one side of the channel 64a and complementary
light receivers 66 are mounted at the opposite side of the
channel 64a. The emitters 65 and receivers 66 co-operate
with the associated slots 61, 62, 63 in the disc 60 to
indicate the orientation of the patient support platform 7
on the base frame 4. Seven infra-red emitter/detector
pairs 65, .66 are used in the optical system to decocie the
positional information. The outer 'track 61 comprises 360
sets of slots 70 and spaces 71. Ideally, a slot 70
occupies 0.5 degree of the circle, a slot 70 and space 71
together occupying 1 degree. The inner track 63 consists
of a number of narrow slots 74, each corresponding to a
locking position in which an associated locking bolt 75
(Fig. 7) is engagable between the base frame 4 and the
patient support platform 7. The locking bolt 75 is
slidably mounted on the base frame 4 for engagement with
and release from associated locking hobs on the ring 9 of
the patient support platform 7. The: locking pin 75 serves
to mechanically anchor the patient support platform 7 on
the base frame 4 and also operates an on/off switch for
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the rotation motor, preventing operation of the motor when
the locking pin 75 is engaged with the patient support
platform 7. Each slot 74 should be exactly in line with
the centre of an associated locking hole 75a on the
patient support platform 7, the narrowness of the slot 74
determining the accuracy of lock positioning. The
intermediate track 62 is used to assign a unique binary
code to each locking position 1. Each locking position
has a set of holes 76 (varying in niunber from one to four.
holes 76). The unique pattern of holes 76 at each locking
position conveys locking angle information to the
controller for controlling rotation of the patient support
platform 7. The binary pattern of the holes is shown in
the table below.
LockPin position Holes 76 (Fig. 21)
D C B A
1 0 C) 0 1
2 0 C) 1 0
3 0 0 1 1
4 0 1. 0 0
5 0 1. 0 1
6 0 2. 1 0
7 0 1. 1 1
8 1 0 0 0
9 1 Ci 0 1
10 1 0 1 0
The binary weighting of the four holes are, A=1, B=2, C=4,
D=8. In the table, the presence of a hole is indicated by
1, absence of a hole by 0.
Seven infra-red emitter detector pairs 65,66 are used in
the optical system to decode the positional information.
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The emitter/detector pairs 65, 66 are positioned at A, B,
C, D, I, X and Y as shown in Fig. 21.
When a detector 66 sees an emitter 65 through a slot or
hole in the disc 60, it produces an output of "1".
Otherwise, it produces an output of "0". The incremental
angle and direction information are i_-ead by X and Y. Every
time a slot 70 passes over detector X, the angle is
incremented or decremented by one. There are two spaced-
apart detectors X and Y for the outer track 61 and the
order in which the detectors X ar.id Y see the emitter
determines the direction. There are four spaced-part
emitter/detector pairs A, B, C, D associated with the
intermediate track 62 and these supply the pattern
information to the controller to compute the locking angle
information. There is one emitter/detector pair I
associated with the inner track 63 and this supplies the
locking position information. As the patient support
platform 7 rotates the spaces between the slots interrupt
infra-red beams passing between emitters 65 and receivers
66 on a support 67 on the base frarae 4. Information from
the infra-red detectors is processed by an optical
processing controller to provide the angle of the patient
support platform 7 which is indicated on a display screen
80 (Fig. 4) at a foot end of the bed 1.
As can be seen in Fig. 7, the pivot linkages 5 have pivot
arms 90, 91 having inner ends which pivotally engaqe the
base frame 4 by pivot pins 92, 93. At one end of the bed
1, an outer end of each pivot arm 90 pivotally engages the
chassis 2 by a pivot pin 94, while at the other end of the
bed 1, the outer end of each pivot arm 91 pivotally
engages the chassis 2 by' pivot pins 95 which are also
longitudinally slidable in elongate slots 96 on the
chassis 2. The rams 6 are operable to rotate the pivot
pins 92, 93 on the base frame 4 for operation of the pivot
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linkages 5.
In use, sensors associated with the side rails 25 and the
panels 16, 17 on the patient support platform 7 are
connected to the drive controller for the patient support
platform 7 such that the patient support platform cannot
be rotated unless all the locks are correctly engaged.
Further the sensors for the straps of the patient
retaining flaps 40, 41 also need to indicate correct
engagement before the patient support platform 7 c:an be
rotated. It will also be appreciated that the delivery of
the patient care lines such as tubes and other cables and
conduits axially outwardly at each end of the patient
support platform greatly facilitates management of the
patient care lines during movement -of the patient support
platform between the supine and prone positions.
It will be noted that when the patie:nt support platform is
rotated from the supine support position into the prone
support position, it will rotate through 200 and then
return to the 180 or zero prone position. This function
will centre the patient on the bed 1.
It will be appreciated that the patient support platform
may be oscillated on the base frame or may be locked. in a
number of fixed orientations on the base frame.
It will also be appreciated that thee invention provides a
patient care line guide system for a hospital bed for
neatly guiding patient care lines off each end of the bed.
The invention is not limited to the embodiments
hereinbefore described which may be varied in both
construction and detail within the scope of the appended
claims.
