Note: Descriptions are shown in the official language in which they were submitted.
SIDE-RAIL ARRANGEMENT WITH SYNCHRONISM
The present invention pertains to a hospital and/or nursing-care bed with a
side
rail arrangement and to a side rail arrangement for mounting on a
corresponding bed.
A side rail is often required on hospital or nursing-care beds to prevent a
person
from falling or rolling out of the bed unintentionally. The side rail extends
along at least
one of the long sides of the bed and can be brought into an in-use position or
into a
not- in-use position. When the rail is in the in-use position, it is expected
to protect the
corresponding long side of the bed or at least part of it. In the not-in-use
position, the
long side is freed, so that the user can get out of bed without hindrance. In
this case
the side rail should not project above the mattress on the bed, because this
would
cause an unpleasant pressure on the upper legs of the person sitting on the
edge of
the bed. In this sense, the side rail arrangement should be structurally as
compact as
possible when in the not-in-use position. The "conversion" from the not-in-use
to the
in-use position and back again should be as easy and intuitive as possible, so
that a
technically untrained person can do it without any special instructions. The
possibility
of incorrect operation should be excluded.
Against the background of these requirements, the problem on which the
invention is based is to achieve a corresponding improvement of known
embodiments.
A side rail arrangement for mounting on a hospital and/or nursing-care bed
comprises a movable side rail element, which comprises bearing regions at the
ends
of the bed opposite each other in the longitudinal direction of the bed, these
regions
being supported movably relative to holding elements. The side rail
arrangement is set
up to generate traction in a traction element when relative movement occurs
between
a bearing region and the associated holding element. The traction results in
and/or
supports relative movement between the bearing region at the other end of the
side
rail element and its associated holding element. The traction comprises in
particular a
pulling movement, i.e., a local displacement of the traction element. In this
way, a
movement can be transferred by way of the traction element from one end of the
side
1
CA 2951752 2018-03-23
rail element to the other in either direction by an amount equal to the
distance by which
the side rail element on the side in question has moved relative to the
associated
holding elements. Unequal movement is an indication that the side rail element
is
canting (or beginning to cant) inside the guide. When a lifting movement is
exerted,
the forces building up in the traction element create a compensating force on
the side
rail element at the end which is lower at the time in question. Certain
sections of the
traction element are preferably aligned with the longitudinal direction of the
side rail
element.
The side rail arrangement preferably comprises a guide with a plurality of
deflection points, especially deflection pulleys, which are supported on the
side rail
element in such a way that, when the side rail arrangement is properly mounted
on the
bed, the traction element has at least one section which is aligned
substantially
vertically, wherein this vertical section of the traction element is provided
with a catch
point, which is arranged in a stationary position relative to the holding
elements. The
traction element is supported by the deflection points (or pulleys). As a
result, the side
rail element can be easily moved vertically. Because the deflection points are
preferably supported inside the side rail element, a compact design is
obtained, which
nevertheless allows the side rail element to move over a long distance.
Alternatively, a guide for the traction element comprises a plurality of
deflection
points, especially deflection pulleys, which are supported on at least one
beam which
is in a stationary position relative to the holding elements, in such a way
that, when the
side rail arrangement is properly mounted on the bed, the traction element has
at least
one section which is aligned substantially vertically, wherein, in the
vertical section, the
traction element is provided with a catch point, which is connected to the
side rail
element. This embodiment involves a variant in which the deflection pulleys
are
attached to the frame of the bed or to an adapter or adapters attached to the
frame.
Thus, it is possible for the side rail arrangement to be implemented easily.
2
CA 2951752 2018-03-23
Two of the previously mentioned catch points are preferably arranged at
opposite ends of the side rail element. As a result, it is possible with only
one traction
element, which is preferably guided from one end to the other and back again
in the
longitudinal direction of the side rail element, to prevent the side rail
element from tilting
and jamming when it is lifted off-center, i.e., either when it is lifted
higher at the head
end or when it is lifted higher at the foot end.
In preferred elaborations, the traction element can comprise a wire, a belt, a
toothed belt, a chain, or the like. This is preferably a flexible element with
high tensile
strength and preferably low elasticity. The traction element can comprise a
set of teeth
to increase the synchronism. In this case, at least two of the deflection
pulleys of the
side rail element can comprise teeth to engage with the traction element and
also an
additional set of teeth, which engages with a toothed rack. The toothed rack
is
stationary relative to the holding elements, so that the gear wheel i.e., the
toothed
deflection pulley can roll over the toothed rack. As a result of the
synchronous
movement of the toothed deflection pulleys, the side rail element is able to
move
vertically without twisting.
In another preferred embodiment, the side rail element comprises a telescoping
element or a hand railing, which is movably supported so that it can be
pulled,
preferably vertically pulled, relative to the side rail element. Thus, the
area protected
by the side rail arrangement can be increased without the height of the side
rail being
increased correspondingly when in the not-in-use position.
The side rail element can comprise in particular a telescoping element or a
hand railing which is connected at one fastening point to a vertically
oriented section
of the traction element. Thus, the movement of the side rail element relative
to the
holding elements is coupled to the relative movement between the telescoping
element
and the side rail element. Thus, with only one movement, the side rail element
can be
moved into its closed position (i.e., the in-use position), and simultaneously
the
telescoping element can be extended. The user can grip either the telescoping
element
3
CA 2951752 2018-03-23
or the side rail element to suit his preference. The point at which the
telescoping
element is attached to the traction element is preferably different from the
point at
which the traction element is attached to the holding element.
Catch positions can also be provided to keep the side rail element and/or the
hand railing in the in-use position and/or in the extended state and/or in at
least one
intermediate position. As a result, the user is given the possibility of the
using the side
rail in intermediate positions.
The side rail element can also comprise a telescoping element or a hand
railing
comprising a lower edge, which, in the non-extended state of the telescoping
element,
lies below the upper edge of the main body of the side rail element. The main
body of
the side rail element is understood as the one-piece component constituting
the main
surface of the side railing arrangement. When the telescoping element is
raised into
the extended position, a gap is created between the upper edge of the side
rail element
and the lower edge of the telescoping element. This gap, for safety reasons,
may not
be greater than 120 mm. Because of the structure described, the distance over
which
the telescoping element can be moved can be greater than the amount cited
without
the gap exceeding the limit of 120 mm.
In particular, a spring, preferably a tension spring, can be connected at one
end
to the traction element and at the other end to the side rail element and set
up so that,
when the side rail element is lowered, the spring will absorb its potential
energy and
store it, wherein the direction in which the tension of the spring acts is
oriented in
particular in the longitudinal direction of the side rail. As a result, it is
easier for the user
to raise the side rail element. The side rail element, furthermore, is
considerably longer
in its longitudinal direction than in its height direction, i.e., the
direction in which the
beam 21 is oriented.
Preferred embodiments of the invention are described in the following on the
basis of figures:
4
CA 2951752 2018-03-23
-- Figure 1 shows a bed with a side rail arrangement, wherein the side rail
arrangement is in the in-use position on one of the long sides of the bed and
in the
freed (i.e., not-in-use) position on the other side;
-- Figure 2 shows the bed of Figure 1, wherein the side rail arrangement is in
the in- use position at the head end along the forward part of the long side;
-- Figure 3 shows a bed with an alternative embodiment of the side rail
arrangement;
-- Figure 4 shows a detail of the movable side rail element with the
deflections
of the cable;
-- Figure 5 shows a schematic diagram of the drive mechanism;
-- Figure 6 shows a view of the side rail arrangement, in which the covers on
the beams 21 have been removed;
-- Figure 7 shows a schematic diagram of an alternative embodiment;
-- Figure 8 shows the detailed view A of the profile of the hand railing
according
to Figure 6; and
-- Figure 9 shows a schematic diagram of another alternative embodiment.
Figure 1 shows a perspective view of a bed 1, in particular a hospital or
nursing-
care bed, in which two side rail arrangements are arranged on each of the two
long
sides of the bed; the two side rail arrangements on one side cooperate to
protect the
entire long side in question, so that a person lying in the bed cannot fall
out of it when
the side rail arrangement is in its in-use position. At the head end, a head
part 2 is
arranged, and at the opposite end, i.e., the foot end, a corresponding foot
part is
present.
Figure 2 shows a side rail arrangement 10 in the foreground and another one
at the head end in its in-use position. A side rail element 20 of the side
rail arrangement
has been pulled upward. The upper edge of the side rail is now at least 12 cm,
preferably at least 14 cm, above the mattress (not shown). This height
guarantees that,
under normal conditions, no one can fall out of the bed unintentionally.
Because two
CA 2951752 2018-03-23
side rail arrangements are arranged along the side of the bed, it is possible
to protect
the head end of the bed (i.e., in the in-use position) and to leave the foot
end
unprotected (i.e., in the not- in-use position). Thus, a person can get out of
the bed
after sliding down toward the foot end. At the same time, however, the head
end is
protected by the side railing arrangement, which is in the in- use position.
It is
frequently desired to secure precisely the head end, so that it is possible to
prevent
the upper body of a person from rolling out of bed first, in which case he/she
might hit
his/her head on the floor.
Each of the four side rail arrangements is preferably identical in design. Two
beams 21 (see Figure 6) of the movable side rail element 20 are attached by
way of
holding elements 30, 30' to the frame 5 of the bed. The two beams 21 have a
vertical
dimension of at least about 30 cm, and the two beams 21 are connected to two
bars
12, which have a height of approximately 120 mm. Between the bars there is a
gap 13
(in the vertical direction) of 120 mm or less. If the gap 13 is greater than
120 mm, it
would be possible for a child, for example, to push his/her head through or
for a person
to get his/her arms or legs caught in it. The movable side rail element 20 is
made as a
one-piece unit and consists preferably of the two beams 21 and the bars 12.
Covers
26 (see Figure 2) are arranged in front of the beams 21 so that the mechanism
shown
in Figure 4 or Figure 5 cannot be seen. Alternatively, the side rail element
can comprise
a continuous plate or grid structure or the like, which extends, for example
over the
entire length of the side rail arrangement minus the areas required for the
bearing
regions.
A comparison of Figure 2 with Figure 3 reveals that the side rail element 20
comprises an extendable hand railing 60. Profiled sections 65 of the hand
railing 60
are guided in guides of the side rail element 20; these sections allow the
hand railing
60 to be pulled upward over a distance of at least 10 cm. There are three
different
variants of the hand railing: First there is an embodiment (not shown) in
which a hand
railing of this type is not used. Second, as shown in Figures 2 and 3, there
is an
6
CA 2951752 2018-03-23
embodiment in which the movement of the main body of the side rail element 20
relative to its holding element 30 is independent of the movement of the hand
railing
60. That is, the user can, independently of the position of the main body of
the side rail
element 20, determine whether the hand railing 60 should be collapsed or
extended.
In a third embodiment, furthermore, there is a direct and/or indirect coupling
of the
extension movement of the hand railing 60 from the main body of the side rail
element
20 to the movement of the side rail element 20 relative to its holding
elements 30. This
third embodiment will be explained first below.
Figure 4 shows a part of the side rail arrangement in which the covers 26 in
front of the beams 21 have been removed. On the right side, the head part 2 of
the
bed is shown, which is attached to the bed frame 5. The bed frame therefore
also
serves as a carrier for the holding element 30. The holding element 30
comprises for
this purpose an angle plate (see Figure 6), to which a section of tubing 31 is
attached,
preferably welded. A guide 25, especially a guide tube, is permanently
connected to
the side rail element 20, and it is guided in a sliding manner inside the tube
section 31
of the holding element 30, so that the side rail element 20 can be moved
vertically over
a distance of 25 cm, preferably of at least 20 cm.
Figure 4 shows an intermediate position. A traction element 50, such as a wire
cable in particular, is attached to a fastening point 56 of the holding
element 30. The
routing of the cable forming the traction element 30 is shown schematically in
Figure
5, wherein the side rail arrangement is in its not-in-use position. Each end
of the
traction element 50 is attached to a fastening point 56 of the side rail
element 20, these
points being attached permanently to the frame 5 of the bed. The traction
element 50
runs first from the fastening point 56 on the right vertically downward, until
it reaches
the lower end of the side rail element 20, where a deflection pulley 55 is
located. The
traction element 50 passes around the deflection pulley 55 and runs toward the
other
end of the side rail element 20, where it passes around another deflection
pulley 55
and then runs to the upper end of the side rail element 20; there it is passes
180 around
7
CA 2951752 2018-03-23
yet another deflection pulley 55 then runs back to the lower end, where it is
deflected
back to the first longitudinal end of the side rail element 20. Because the
configurations
of the deflection pulleys 55 at the two ends of the side rail element 20 are
identical, the
same deflections occur at both ends of the rail element before the ends of the
cable
arrive back at the fastening points 56 to which they are attached. Identical
fastening
points 56 are provided at the two axial ends of the side rail element 20. To
facilitate
the mounting of the steel cable, it is possible, in a preferred embodiment, to
provide a
turnbuckle in the horizontal section of the cable 50 in the adjacent area.
This
connection can be provided in particular in the area of the spring 70.
All six deflection pulleys 55 are supported on the movable side rail element
20.
When the side rail element 20 is now moved upward (see the vertical arrows
above
the ends of the side rail element), the traction element 50, lying parallel
(see the two
horizontal runs of the cable at the bottom of Figure 5) between the ends of
the side rail
element 20, moves in the directions shown by the arrows. When the side rail
element
20 is lifted in the middle, only insignificant forces built up within the
traction element.
When the user grips the side rail off center and then exerts a lifting force
on one side,
as indicated by the force Fl, a large asymmetric force is exerted on the
traction
element at point P1. As previously described, the traction element 50 is
guided to the
other end of the side rail element 20 and is attached permanently there to the
frame of
the bed 1 at the fastening point 56. These force conditions have the result of
producing
an upward-directed force on the deflection pulley 55 designated P2, and this
opposes
a tilting or jamming of the side rail element 20. In this way, the force
acting vertically
upward on the side rail element 20 at point P2 compensates for the asymmetric
force
El at the other end of the side rail element 20. Thus, as a result of the way
in which
the cable is guided, it is possible for the user to grip the side rail
arrangement even at
an off- center point and to move it without it becoming tilted or jammed. The
length of
the arrows symbolizes the speed of the movement. Thus, the hand railing 60
moves
at twice the speed of the main body of the side rail element 20 relative to
the bed frame.
8
CA 2951752 2018-03-23
Figure 5 also shows the hand railing 60, which is supported within the main
body of the side rail element 20. Profiled guide sections 65 of the hand
railing 60 are
supported inside the guides 25 of the side rail element 20 (see Figure 4). The
hand
railing 60 is connected by connecting rods 67 to the traction element 50 at
fastening
points 66, and the previously described displacements which occur when the
main
body of the side rail element 20 is lifted have the effect that, when the
cited main body
20 is lifted, the hand railing 60 is pushed out of it. In addition, Figure 5
shows a tension
spring 70, one end of which is connected to the traction element 50, while the
other
end is supported on the side rail element 20. In the position shown, the side
rail
arrangement 10 is in the down, not-in-use position, and thus the tension
spring 70 is
stretched out. When the side rail element 20 is moved upward, the tension
spring 70
is relaxed, gives back the force absorbed when the side rail was lowered, and
thus
reduces the force required to life the side rail element 20. The energy which
is
absorbed during the lowering movement, furthermore, has the result that the
side rail
element does not simply drop down without any resistance.
The previously described connection by way of the connecting rod 67 from the
hand railing 60 to the traction element 50 at the fastening point 66 is
optional. If this
connecting rod 67 is not present, the user can actuate the hand railing 60
independently of the position of the main body of the side rail element 20
relative to
the frame 5 of the bed. This situation is shown in Figure 6. To hold the hand
railing 60
in the upper, i.e., extended, position, catches are provided (not shown). By
means of
actuators 68 arranged in the hand railing 60, the catches can be released. For
this
purpose, Bowden cables (not shown), which are connected to the actuators 68,
are
guided through the interior of the profiled sections 65 and connected to
locking bars
(not shown), which lock when the hand railing 60 is raised and which can be
released
by the Bowden cables.
The relevant specifications require that a side rail must end at least 220 mm
above the level of the mattress to prevent reliably the occupant from falling
out.
9
CA 2951752 2018-03-23
Nevertheless, there are persons who feel constricted when the side rail is
this high.
These persons may believe that a low side rail provides enough safety for
them. For
this reason, the above- described side rail offers two different height
settings. The side
rail arrangement, when in its in-use position, ends at a height of 280 mm
above the
mattress support when the hand railing 60 is not extended. The mattress lies
on the
mattress support. At an average mattress thickness of 140 mm, the conditions
required
by the specifications are not yet fulfilled. For this reason, the hand railing
60 is used,
which, in the extended state, ends at a height of 400 mm above the mattress
support.
Because the hand railing 60 acts as a side rail, the specified conditions can
thus be
satisfied.
Figure 7 shows a schematic diagram of an alternative embodiment of the
mechanism for preventing jamming with two pulleys 59, each of which is
supported on
the side rail element 20. An endless belt passes around these pulleys 59 to
bring about
their synchronous movement. This belt acts as a traction element. In addition,
other
traction elements are attached at their first ends to the side rail element 20
and at their
other ends to stationary points so that, as previously described, the side
rail element
20 is prevented from tilting and jamming. In yet another alternative (not
shown), it is
possible to use one or preferably two Bowden cables to transfer the forces.
Figure 8 shows a variant of a detail of Figure 6. Here a lower edge 69 of the
hand railing in its unextended state lies below the upper edge 29 of the side
rail element
20. The lower edge 69 and the upper edge 29 preferably extend over the entire
length
of the side rail in its longitudinal direction. As previously explained, the
gap 14 (see
Figure 6) between the hand railing 60 and the main body of the side rail
element 20
may not be greater than 120 mm, because otherwise there could be the risk of
injury
Because of the previously described downward projection 69 of the hand railing
60,
the gap 14 present after the hand railing 60 has been extended is reduced even
though
the railing is extended by the same amount, which leads to a corresponding
increase
in the maximum extension of the hand railing 60.
CA 2951752 2018-03-23
In the embodiment of Figure 9, two pulleys 55 are supported on the side rail
element 20, each of which preferably has a first set of teeth, which are in
contact with
the traction element 50, which is preferably configured as a toothed belt. In
addition,
the pulleys 55 comprise a (second) set of teeth, which are in contact with the
toothed
racks 90, which for their own part are permanently mounted on the holding
elements.
Because the traction element is routed in such a way that it crosses itself,
as shown,
the two ends of the side rail element 20 will travel in parallel fashion in
analogy to the
description given above.
In another alternative embodiment, in contrast to what has been explained
above, it is not necessary for the deflection pulleys to be supported on the
movable
side rail element 20. Instead, some or all of the pulleys can be mounted on
the beam
21 and/or on a part of the frame of the bed and/or on holding elements
attached to the
bed. Because, as previously described, what is important is the transfer of
the
movement from the bearing region 22, 22' to the holding element 30, 30', the
result is
the same when the pulleys are mounted in stationary fashion on the frame 5 of
the
bed.
The terms "above'', "below", and "in the vertical direction", etc., always
pertain
to a side rail arrangement which is properly mounted on the bed. A slanted
position of
the bed frame is not considered here. In the description of the side rail
arrangement,
mention has been made of its beams and bars. These are not essential to the
invention, however, because what is important is only the arrangement of the
moving
parts relative to the side rail element.
11
CA 2951752 2018-03-23
