EP3138549A1

EP3138549A1 - Person-support apparatus with adjustable side rail

Info

Publication number: EP3138549A1
Application number: EP15306352.4A
Authority: EP
Inventors: Etienne Yvernault
Original assignee: Hill Rom SAS
Current assignee: Hill Rom SAS
Priority date: 2015-09-02
Filing date: 2015-09-02
Publication date: 2017-03-08

Abstract

The present invention relates to a person-support apparatus including a substantially rectangular support surface, and a side rail support member at least one end of the support surface, the support member extending above the support surface, the apparatus further including a side rail assembly moveable along and supported by the support member and comprising a first upper side rail and a second lower side rail parallel to the first side rail, at least one cross rail coupling the side rails, and a first lower track below the support surface and parallel to the upper and lower side rails, wherein the upper side rail includes a second upper track parallel to the lower track and wherein the upper end of the cross rail is pivotably connected to an upper slider running within and or along the upper track, the lower end of the cross rail is pivotably connected to a lower slider running within or along the lower track and an intermediate portion of the cross rail is pivotably connected to the lower side rail.

Description

The present invention is concerned with person-support apparatus, such as a bed, and with a side rail or side rail assembly suitable for use with such person-support apparatus. It is more particularly suitable for adjustable side rails for a hospital or long-term care (LTC) bed.
Known person support apparatus, such as hospital and LTC beds, include a patient support surface, such as a mattress. Such beds also include side rails. The side rails can be lowered to facilitate patient movement into and out of the bed. The side rails can also be raised to safeguard the patient. When the side rails are raised, they typically extend higher than the support surface of the bed.
EP 2,186,500 discloses a patient bed with four support posts and two pairs of side rails running between two separate pairs of support posts. The support posts are arranged such that there is one at the foot end of the bed, two at the middle of the side of the bed and one at the head end of the bed. Each of the two pairs of side rails engages one of the foot end or head end support posts, and one of the middle support posts. The side rails each include, at each of their ends, a gripping element which groups round the outside of a support post and allows the side rail to slide relative to that support post. Each of the side rails can move independently of each of the other side rails. The four support posts can all be rotated downwards so as to be moved to be in a horizontal position so as not to obstruct entry and exit of a patient from the bed.
Arrangements such as that disclosed in the EP 2,186,500 are complicated with many moving parts and therefore prone to failure and relatively expensive to produce. The need for central pillars in the middle of a side of the bed also means there is a need for a mechanism to lower the central pillars to allow a patient to leave the bed (and raise it again afterwards).
US 3,055,020 discloses a restraining structure for a bed which includes two pivotable upright members or support posts with side rails pivotably coupled thereto. One upright member is arranged at one end of the bed and the other upright member is part of the way down the bed. Both upright members or support can pivot from an upright position to a lowered position. In the lowered position, a patient can leave the bed. The side rails and upright members together form a parallelogram arrangement. The arrangement of US 3,055,020 requires that one leave a significant space for the structure to be moveable between the upright and lowered positions as the upright members rotate around their respective pivot points at their bottom end. This arrangement cannot therefore be used to create a restraining structure across the whole side of a bed. The arrangement of parallelogram arrangements such as that US 3,055,020 require an additional relatively complicated restraining mechanism to ensure that side rails do not pinch the fingers of a patient or carer when in the lower position or being lowered into that position.
Thus the need exists for further contributions in this area of technology.
When in the foregoing description and claims, relative and/or spatial terms such as, for example, upper, lower, side, head end, foot end, external, internal, vertical and horizontal are used, they relate to the positions taken up when the apparatus is in use, or arranged ready for use.
The present invention in a first aspect provides person-support apparatus including a substantially rectangular support surface, and a side rail support member at at least one end of the support surface, the support member extending above the support surface, the apparatus further including a side rail assembly moveable along and supported by the support member and comprising a first upper side rail and a second lower side rail parallel to the upper side rail, at least one cross rail coupling the side rails, and a lower track below the support surface and parallel to the upper and lower rails, wherein the upper side rail includes an upper track parallel to the lower track and wherein the upper end of the cross rail is pivotably connected to an upper slider running within and or along the upper track, the lower end of the cross rail is pivotably connected to a lower slider running within or along the lower track and an intermediate portion of the cross rail is pivotably connected to the lower side rail.
The inventors have appreciated that such a construction allows one to provide a side rail assembly which only needs a support at one end. The combination of the pair of side rails connected by the defined cross rail construction, with the movement of the side rail assembly along a support member and slidable engagement between the cross rail and the two tracks renders possible a robust and simple side rail construction which allows for a side rail assembly which can be raised and lowered and which only needs a support member at one end of the patient support surface. This means that there is no need for the problematic additional central support member required in constructions like that shown in EP 2,186,500 . The lower track may be attached to either end of the height adjustable supports, and may be attached above the support surface, or by any other similar arrangement.
Preferably, the side rail support member is substantially vertical.
Preferably, the side rail support member is located at a corner of the support surface.
Preferably, the person-support apparatus includes two substantially parallel cross rails coupling the side rails and wherein the upper end of each of the two cross rails is pivotably connected to a respective upper slider running within and or along the upper track, the lower end of each cross rail is pivotably connected to a respective lower slider running within or along the lower track and an intermediate portion of each cross rail is pivotably connected to the lower side rail. Such a construction is simple and robust.
Preferably, the person-support apparatus includes two sets of parallel side rails, a first head end set of side rails at the head end of the person-support apparatus and moveable along and supported by a first head end support member, and a second foot end set of side rails at the foot end of the person-support apparatus and moveable along and supported by a second foot end support member. This allows one to separately raise the head and/or foot end sets of side rails and thereby, for example, have the foot end lowered and the head end raised to allow egress of a person from the person-support apparatus via the foot end while using the raised or deployed head end set of side rails as an egress handle or support.
Preferably, the head end support member and the foot end support member are located adjacent respective corners of the patient support surface. Such a person-support surface has support members located away from the area of the bed through which persons or patients enter or leave the apparatus and therefore makes for a simpler entry or exit.
The invention in a second aspect provides a person-support apparatus including a substantially rectangular support surface and a side rail support member extending from below or near the support surface to above the support surface, the apparatus including a side rail assembly moveable along and supported by the support member and comprising a first upper side rail and a second lower side rail parallel to the upper side rail and at least one cross rail coupling the side rails wherein a first portion of the cross rail is pivotably connected to the upper side rail and a second portion of the cross rail is pivotably connected to the lower side rail, characterised in that the side rail assembly is moveable along the support member between a first retracted position and a second fully deployed position in which the two side rails are further apart from each other in the deployed than in the retracted position and wherein the cross rail is shaped such that the tangent to the edge portions of the cross rail adjacent to the respective portions of each the side rails subtends an angle of greater than 70° relative to the respective longitudinal edge of the respective side rail, when the side rail assembly is at the first retracted position, the second deployed position and as it moves between the first retracted and second deployed position.
The inventors have appreciated that it is possible to provide a robust side rail assembly which can be easily raised and lowered (or deployed and retracted) and which reduces the likelihood that a person will get his or her fingers trapped and hurt by using an arrangement involving a side rail assembly pivotally connected to a cross rail and hence opening in a parallelogram or scissor-like configuration in which the shape of the cross rail has been carefully selected.
Preferably, the cross rail is shaped and the pivots are arranged such that when the side rail assembly is in its retracted position the side rails are spaced apart. This further reduces the risk of trapping fingers.
The invention in a third aspect provides person-support apparatus including a substantially rectangular support surface and two side rail assemblies extending along a side of the rectangular support surface, the two side rail assemblies including a first head end side rail assembly and a second foot end side rail assembly and wherein the side assemblies are each moveable between a first retracted position below the support surface and a second deployed or extended position extending from below to above the support surface to hinder egress of a patient from the support surface, wherein the foot end side rail assembly cannot be moved from its retracted position to its deployed position unless the head end side rail assembly is in its deployed position. Such an arrangement means that a person or patient cannot raise the foot end side rail assembly without first raising the head end side rail assembly. This reduces the risk of a patient being trapped in the apparatus.
Preferably, the apparatus includes a first lower track below the support surface, the head end side rail assembly including a first head end side rail slider element running within or along the lower track as the head end side rail assembly moves between its retracted and deployed positions and the foot end side rail assembly also including a first foot end side rail slider element running within or along the lower track as the foot end side rail assembly moves between its retracted and deployed positions, and wherein the slider elements are adjacent each other when the side rails are in the retracted position such that the first head end slider element blocks movement of the first foot end slider element so as to prevent the foot end side rail assembly moving from its retracted to its deployed position when the head end side rail assembly is in its retracted position. Such an arrangement is a simple and robust mechanism which reduces the risk of patient entrapment when, for example, a backrest at the head end of the apparatus has been raised and the patient is in an upright or seated position.
Embodiments of the invention will now be described by way of non-limiting example with reference to the accompanying drawings, in which:

Figure 1 is a perspective view illustrating an embodiment of the invention with two pairs of side rails arranged with one pair lowered or retracted so as to permit egress of a patient from a bed;
Figure 2 is a side perspective view of the embodiment of figure 1 but with both pairs of side rails lowered;
Figures 3a and 3b are, respectively, external and internal side views of the side rails in the positions illustrated in Figure 2;
Figure 4 is a detailed internal view of the side rail in the position illustrated in Figure 2;
Figures 5a and 5b are detailed internal views of the side rails in the lowered position;
Figures 6a, 6b, 6c and 6d are internal and external side views of the side rails in partially and fully raised positions to demonstrate the movement of the slide elements;
Figures 7a and 7b are external and internal side views showing the relative movement of the side rails during raising;
Figure 8 is an internal view of the side rails with one rail raised;
Figure 9 is an internal view of the side rails showing that the foot end side rail alone cannot be raised;
Figure 10a and 10b are side and perspective views of the support apparatus respectively showing that the foot end side rail alone cannot be raised;
Figures 11 a and 11 b are side views of an alternative embodiment of the invention;
Figures 12a and 12b are, respectively, an external side view and a partial exploded side view of the side rail assembly of Figure 2 illustrating how it reduces the risk of finger entrapment;
Figures 13a and 13b are, respectively, an external side view and a cross-section along the line X-X of Figure 13a of the side rail assembly of Figure 1 illustrating how it reduces the risk of finger entrapment;
Figures 14a, 14b, 14c and 14b are internal side views and partial exploded side views of, respectively, the partially raised side rail assembly and one fully extended side rail assembly illustrating the angles between the side rails and the cross rails;
Figure 15 illustrates how the angle between the tangent to the cross rail and a line tangent to a constant circle at the pivot of a cross rail is constant;
Figures 16a, 16b, and 16c illustrate the movement of a cross rail between its retracted or lowered and its deployed or raise positions.

A person-support apparatus 1 according to one illustrative embodiment is shown in Figure 1. The person-support apparatus can be a hospital bed or a LTC (Long Term Care) bed. The bed includes a lower frame or base and an upper frame supported on a plurality of telescopic or height-adjustable supports above the lower frame (as described in EP 2,314,267 ). The upper frame includes a patient support surface deck on which a mattress or other patient support element can be supported and whose upper surface defines or provides a patient support surface 2. The telescopic supports allow the height of the patient support surface to be adjusted by moving the upper frame with respect to the lower frame. It should be appreciated that the person-support apparatus can also be a hospital stretcher, an operating table, or any other apparatus configured to support a person thereon. The person-support apparatus can support a substantially rectangular person-support surface (which may be a mattress) on the upper frame.
The person-support apparatus has a footboard 3 at a first foot end 4 of the bed 1 and a headboard 5 at the second head end 6 of the bed. The footboard and headboard are fixed to the respective foot and head ends of the lower frame. A deck is supported within the space defined by the footboard 3 and headboard 5 to form a person-support surface 2, or to support a mattress which forms a person-support surface 2. Two side rail assemblies 7, 8 are provided for a first side of the bed. The other side of the bed (not shown in figures) may have similar side rail assemblies, or any other form of side rail assembly, or no side rail assembly at all.
Each side rail assembly 7, 8 is attached at one end to a respective one of the footboard 3 or headboard 5. Each side rail assembly is a pair of coupled side rails 9, 10 or side rail bars. As shown, for example, in Figure 1 and Figure 2, the ends of each of the side rails are attached to a respective slider which engages a groove 12 in the end of the respective end board 3, 5. The slider may include a tapered upper end to facilitate insertion into the groove 12 or slot and is fixed to each of the side rails 9, 10 by a pin or projection which passes through the respective side rail bar. The bottom of the groove or slot has an angle opening to facilitate insertion of the slider. The construction of the slider and associated groove 12 may be as described in EP 2644176 .
The end boards may each include an end board latching assembly at the bottom end which allows removal and insertion of the slider assembly (and hence the slide rail assembly). The end board latching mechanism holds the side rail assembly in the end board groove and may be as described in EP 2644176 .
As discussed briefly above, each side rail assembly includes a pair of side rails 9, 10. The external side of these side rails 9, 10 can be seen in Figure 3a, while Figure 3b shows the internal side of the side rails 9,10. The pair of side rails are coupled by cross rails 13 which are pivotably coupled at their first or upper end 14 to the upper side rail 9 and at an intermediate portion 15 to the lower side rail 10. The second, lower or bottom end 16 of each cross rail is pivotably coupled to the track 17.
Figure 4 shows the internal side of the side rails 9, 10 in the lowered or retracted position. The bottom end 16 of each cross rail 13 is pivotably connected via a bolt or pivot 18 to a frame slider element 19 which is slideable in a groove or channel 20 in the track17. The bottom ends 16 of the two cross rails on both connected to a single lower frame slide element 19. Similarly, the top or first end 14 of each cross rail 13 is pivotably connected via a bolt or pivot 21 to an upper slider element 24 which is slideable in a groove or channel 22 in the top or upper side rail 9. The top ends 14 are each connected to separate slide elements 24. The intermediate portion 15 of each cross rail is pivotably connected to the lower side rail 10 by a pivot or bolt 23. This arrangement is shown in more detail in Figures 5a and 5b.
The movement of the slide elements can be seen in Figures 6a and 6b when only the head pair of side rails is raised, and in Figures 6c and 6d when both pairs of side rails are raised or deployed. Figures 6a to 6d also show the positioning of track 17. The track 17 is located below the patient support surface, extending between opposing telescopic or height-adjustable supports.
These arrangements with the tops and bottoms of each cross rail 13 pivotably connected to elements 19, 24 which can move parallel to the patient support surface 2, track 17 and side rails 9, 10 mean that it is possible to have a parallelogram arrangement in which the side rails 9, 10 themselves only move perpendicular to the patient support surface 2 and/or side 25 of the frame as the side rails are moved together downwards (and towards the frame) and apart upwards (and away from the frame). This movement is shown in Figures 7a and 7b.
The cross rails 13 are disposed so that when the side rails 9, 10 are in the lowered or retracted position they are each angled away from the foot end 4 of the bed, with the lower end 16 of each cross rail 13 being closer than the upper end 14 of the respective cross rail, to the foot end 4 of the bed. This arrangement means that when lifting the side rails from the lowered position it is necessary that the lower frame slide elements 19 move away from the foot end 4 and the top slide elements 24 move towards the foot end, as shown in Figure 8. The cross rails 13 are also shaped such that when the side rails are lowered the lower frame slide element 19 of the rear most (head end side rail assembly) cross rail is adjacent the lower frame slide element 19 at the foremost foot end side rail assembly cross rail as shown in Figure 9. This prevents the foot end side rail assembly being raised without the head end side rail assembly having also been raised, as shown in Figure 10a, which risks patient entrapment, as shown in Figure 10b.
Similarly, the cross rails are disposed such that when the side rail assemblies are both in the fully raised position (see Figure 6d), the cross rails 13 are each angled away from the foot end 4 of the bed, with the lower end 16 of each cross rail 13 being closer to the foot end, 4 than is the upper end 14 of each cross rail. This arrangement means that when dropping the side rails from the fully raised position it is necessary that the lower frame slide elements 19 move away from the head end 5 and the top slide elements 24 move away from the foot end 9. The cross rails are also shaped such that when the side rails are lowered the lower frame slide elements 19 of the rear most head end side rail assembly cross rail is adjacent the lower frame slide element 19 of the foremost foot end side rail assembly cross rail. This prevents the head end side rail assembly being lowered from the fully raised position without the foot end side rail assembly having also been lowered.
The same safety feature could be achieved by the side rail arrangement shown in Figures 11 a and 11 b. In this example, the upper side rail 9 of the head end assembly 7 includes an extension 33 that protrudes towards the foot end 4 of the bed 1. The extension 33 is provided at a height such that the lower face of the extension 33 lays adjacent to the top face of the upper side rail 9 of the foot end assembly 8 when both side rail assemblies are in the lowered position. In this way, the foot end side rail assembly 8 can not be raised without abutting the extension 33. Similarly, when both side rail assemblies 7, 8 are in the raised position, the head end assembly 7 can not be lowered without also lowering the foot end assembly 8, since the extension 33 engages with the upper side rail 9 of the foot end assembly 8 to prevent relative movement between the rail assemblies 7, 8.
Each cross rail 13 is curved away from the upper surface 27 of the lower respective side rail 10 between its intermediate position 15 and top ends 14 so as to increase the space between the cross rail 13 and side rails 9, 10 and thereby reduce the likelihood of fingers being pinched between a cross rail 13 and side rail 9, 10 as the side rail assemblies are raised and lowered. The cross rails 13 are also shaped so that when the respective side rail assembly is retracted there is a gap between the top edge of the lower side rail 10 and the lower edge of the top side rail 9. This gap should be larger than the diameter of a finger so as to reduce further the risk of trapping fingers. This is shown in Figures 12a and 12b, wherein the circle 30 reflects an area larger than the diameter of the average human finger, and demonstrates that there is space between the cross rails 13 and the side rails 9, 10 to prevent fingers being trapped.
The cross rails also each have a stepped construction with such that the lower ends 16 are stepped back from the inner surface of the lower siderails 10 to provide a gap larger than the diameter of a finger between the inner surface of the bottom or lower side rails 10 and the bottom portion 16 of the cross rails. A gap of 25 mm is a possible gap. A 25 mm circle 30 representing a finger is shown illustrate the gap. This gap is shown in Figure 13b. Each cross rail 13 is shaped such that at all positions (i.e. when retracted, fully deployed and positions between retracted and fully deployed) the tangent of the edge of the cross rail in contact with the edges of the respective side rail is always sustained at an angle of at least 70°. This angle is shown in Figure 14b when the side rail 13 is partially raised, as shown in Figure 14a, and in Figure 14d when the side rail 13 is fully raised or deployed as shown in Figure 14c. This is made clearer in Figure 15, which shows that the shape of the curve of each cross rail 13 may be defined by a portion of a spiral in which the tangent and a line tangential to a constant circle at its centre of rotation is always 70°.
As shown in respectively Figures 16a, 16b and 16c, the angles subtended by the edges closer to the foot end of the bed and contacting the upper side rail bottom edge are 90°, 90° and 95° in the described specific embodiment. As shown in the figures, the cross rail pivots 18, 21, 23 are arranged so they do not form a straight line. The cross rails are each substantially L-shaped or boomerang-shaped with the top portion 14 curving away from the lower end 16.
The side rail assemblies may be locked into position (whether retracted, deployed or at selected positions in between) using the latching mechanism described in EP 2644176 . The contents of EP 2644176 are hereby incorporated into this application by way of reference.

Claims

A person-support apparatus including a substantially rectangular support surface, and a side rail support member at least one end of the support surface, the support member extending above the support surface, the apparatus further including a side rail assembly moveable along and supported by the support member and comprising a first upper side rail and a second lower side rail parallel to the first side rail, at least one cross rail coupling the side rails, and a first lower track below the support surface and parallel to the upper and lower side rails, wherein the upper side rail includes a second upper track parallel to the lower track and wherein the upper end of the cross rail is pivotably connected to an upper slider running within and or along the upper track, the lower end of the cross rail is pivotably connected to a lower slider running within or along the lower track and an intermediate portion of the cross rail is pivotably connected to the lower side rail.
A person-support apparatus according to claim 1 wherein the support member includes a support track and the side rail assembly includes a slider running within or along the support member track.
A person-support apparatus according to any preceding claim wherein the upper and lower side rails are substantially horizontal.
A person-support apparatus according to any preceding claim wherein the side rail assembly is slidable along the support member, and the support member track is substantially perpendicular to the support surface.
A person-support apparatus according to any preceding claim including two substantially parallel cross rails coupling the side rails and wherein the upper end of each of the two cross rails is pivotably connected to a respective upper slider running within and or along the second upper track, the lower end of each cross rail is pivotably connected to a respective lower slider running within or along the first lower track and an intermediate portion of each cross rail is pivotably connected to the second lower side rail.
A person-support apparatus according to claim 5 wherein the lower end of each of the two cross-rails are pivotally connected to a single common slide running within or along the first lower track.
A person-support apparatus according to any preceding claim wherein the upper end of the or each cross rail is pivotably connected to the respective upper slider at an upper cross rail pivot, the lower end of the or each cross rail is pivotably connected to the respective lower slider at a lower cross rail pivot and the intermediate potion of the or each cross rail is pivotably connected to the second lower side rail at an intermediate cross rail pivot, and wherein a line between the upper and intermediate cross rail pivots subtends an angle θ relative to the line between the lower and intermediate cross rail pivots, where θ is not 180°.
A person-support apparatus according to claim 7 wherein the cross-rails are substantially L-shaped with the longitudinal axis of an upper portion curving away the longitudinal axis of a lower portion.
A person-support apparatus according to any preceding claim including two side rail assemblies, a first head end set of side rails at the head end of the person-support apparatus and moveable along and supported by a first head end support member, and a second foot end set of side rails at the foot end of the person-support apparatus and moveable along and supported by a second foot end support member.
A person-support apparatus according to claim 9 wherein the head end support member and the foot end support member are located adjacent respective corners of the patient support surface.
A person-support apparatus including a substantially rectangular support surface and a side rail support member extending from below or near the support surface to above the support surface, the apparatus including a side rail assembly moveable along and supported by the support member and comprising a first upper side rail and a second lower side rail parallel to the first side rail and at least one cross rail coupling the side rails wherein a first portion of the cross rail is pivotably connected to the upper side rail and a second portion of the cross rail is pivotably connected to the lower side rail, wherein
the side rail assembly is moveable along the support member between a first retracted position and a second fully deployed position in which the upper side rail and the lower side rail are further apart from each other in the deployed than in the retracted position and wherein when the side rail position is in the first retracted position, the second fully deployed position and a position therebetween, the perimeter or edges portions of the cross rail are shaped such that the tangent to the edge portions of the or each cross rail adjacent to the respective portions of each the side rails subtends an angle of greater than 70° relative to the respective longitudinal edge of the respective side rail.
A person-support apparatus wherein the cross-rail is shaped such that there is a gap of at least 25 mm between the bottom edge of the upper side rail and the top edge of the lower side rail when the side rail assembly is in its first retracted position.
A person-support apparatus according to any of claims 11 and 12 and any of claims 1 to 10.
A person-support apparatus including a substantially rectangular support surface and two side rail assemblies extending along a side of the rectangular support surface, the two side rail assemblies including a first head end side rail assembly and a second foot end side rail assembly and wherein the side assemblies are each moveable between a first retracted position below the support surface and a second deployed or extended position extending above the support surface to hinder egress of a patient from the support surface, wherein the foot end side rail assembly cannot be moved between its retracted and deployed position unless the head end side rail assembly is in its deployed position.
A person-support apparatus according to claim 14 including a first lower track below the support surface, the head end side rail assembly including a first head end side rail slider element running within or along the first lower track as the head end side rail assembly moves between its retracted and deployed positions and the foot end side rail assembly including a first foot end side rail slider element running within or along the lower track as the foot end side rail assembly moves between its retracted and deployed positions, and wherein the head end rail slider element and the foot end rail slider element are adjacent each other when the head end side rail assembly and the foot end side rail assembly are in the retracted position such that the head end rail slider element blocks movement of the foot end rail slider element so as to prevent the foot end side rail assembly moving from its retracted to its deployed position when the head end side rail assembly is in its retracted position.
A person-support apparatus according to claim 15 comprising a side rail support member at at least one end of the support surface, the support member extending above the support surface, the head end and foot end side rail assemblies being moveable along and supported by the support member and each comprising a first upper side rail and a second lower side rail parallel to the first side rail, at least one cross rail coupling the side rails, and a first lower track below the support surface and parallel to the upper and lower side rails, the upper side rail includes a second upper track parallel to the lower track and wherein the upper end of the cross rail is pivotably connected to an upper slider running within and or along the upper track, the lower end of the cross rail is pivotably connected to a lower slider running within or along the lower track and an intermediate portion of the cross rail is pivotably connected to the lower side rail, and wherein the head end and foot end side rail assemblies share a single first lower track, and the cross rail pivots are arranged such that the first head end and foot end side rail slider elements slide from the head to the foot end of the common lower track as the respective side rails are raised from their lowermost or retracted position.
A person-support apparatus according to any of claims 1 to 13, and any of claims 14 to 16.