GB2617570A

GB2617570A - Intensive care chair

Info

Publication number: GB2617570A
Application number: GB2205321.9A
Authority: GB
Inventors: Thompson Nathan
Original assignee: Caremed Alrick Uk Ltd
Current assignee: Caremed Alrick Uk Ltd
Priority date: 2022-04-11
Filing date: 2022-04-11
Publication date: 2023-10-18
Also published as: GB202205321D0

Abstract

A chair with a back, seat and leg rest wherein the leg rest 230 can be folded or retracted below a seat 220 to allow a user to place their feet under a front of the seat to be under their centre of mass. The leg rest may be up to 50mm behind the front edge of the seat and be pivotally mounted on a hinge which can be moved to a retracted position. The leg rest may move between horizontal and vertical positions and may be retracted along a low friction slide mechanism by a piston 270. The piston may be arranged to only pivot the leg rest once it translates to a forward position. The chair may be an assisted standing chair for an intensive care or trauma unit with lifting or tilting means to help a user stand. The back rest may move to a vertical position to act as a bed.

Description

Assisted Standing Chair

Technical Field

The present invention relates to chairs including mechanisms to assist a seated person in standing, and to the related mechanisms. The invention is particularly applicable in the field of intensive care and trauma chairs.

Background

For the infirm, rising from a seated position can be difficult or impossible without assistance. In the critical and intensive care settings patients recovering from an 15 operation or illness may not be able to stand unassisted.

Chairs aiding the occupant to stand are known in various settings, from the home to hospitals. In the home setting, these are often limited to a simple lift and tilt motion of the seat, to assist the occupant with the initial part of the standing motion and to bring their bodyweight forward onto their feet.

Intensive care and trauma chairs are more specialised. They are intended to allow a recovering patient to sit up in comfort, but can be quickly reclined to a flat or substantially flat bed-like position in case the patient suffers any complications and needs to be laid flat to be treated. These chairs are typically mobile, being mounted on a wheeled frame, and height adjustable, by a piston or motor, to allow the patient to be transferred directly to/from a bed or operating table. For these purposes, the frame must be sufficiently long and wide to remain stable during motion and patient transfer without the chair tilting or toppling over.

An intensive care chair or trauma chair should even be stable to accommodate the patient whilst the chair is reclined flat and being wheeled around.

As well as it being beneficial to be able to return a patient quickly to a reclined position in the case of need for urgent treatment, it is also known that recovering patients will in many cases recover more fully and more quickly if they are able to be mobilised and rehabilitated at an early stage of their recovery. This process is facilitated by the chair being motorized or otherwise mechanically actuatable and thus operable to sit the patient up and to bring the patient towards a standing position.

The design of such chairs imposes a number of constraints, since the shape of the chair in the bed-like configuration must be sufficiently long and wide to accommodate larger patients. The padding of the chair must also be necessarily thick and bulky so that it is comfortable for the Patient to sit and lie in the chair for long periods of time. The chair must also accommodate the piston or motor used to lift and lower the chair seat, and other components, in the frame space beneath the seat, limiting the minimum height to which the seat can be lowered. These factors can make it challenging for an infirm patient to stand up from or sit down into such chairs.

Figure 1 shows an intensive care chair in a partially reclined seated position. The chair includes a wheeled frame to which a lifting piston is mounted. The chair has a seat that is mounted onto the lifting piston, as well as a back and a leg rest. The chair back and leg rest are pivotally coupled to the seat at its respective back and front ends. The chair is motorized and can be operated to pivot each of the back and the leg rest independently in order to move a patient between lying and seated positions. The lifting piston can be operated to raise and lower the seat.

Figure 2 shows the same chair in a fully reclined, bed-like configuration. It can be seen that the height of the seat has been raised in Figure 2 as compared with Figure 1 by extension of the lifting piston below the seat. This is done in order to bring the bed surface up to the typical height of a hospital bed or an operating table, at which height it is easier for nurses to attend to the patient and at which height direct sliding transfer of the patient from the chair to a hospital bed or an operating table can be achieved without needing to use a hoist.

Figure 3 shows an example of a similar chair in a situation of use, in which a patient is attempting to sit in or stand from the chair in its lowered, upright seating position. This figure illustrates a limitation that may be addressed by embodiments of the present invention.

In particular, when the patient is attempting to stand, it can be seen that the position of the chair forces the patient's feet to be in front of the leg rest. As a consequence, the patient's centre of mass is not over their feet, and their weight force is pulling them down into the seat. Although the seat can be raised and tilted forward to assist the patient, it cannot bring their centre of mass over their feet. For infirm and/or overweight patients, it can be impossible for the patient to raise themselves up onto their feet without assistance, as it is awkward for them to push up from the seat with their arms and they may lack the required strength.

For patients who are able to propel themselves from the seat, 30 the transfer of body-weight onto their feet may not be stable, and there is a risk that the forward momentum may unbalance them and cause them to fall forward.

Summary of the Present Invention

The present invention has been made in view of the realisation and recognition by the inventors of the aforementioned problems which may arise in prior art designs. The present invention seeks to alleviate or solve one or more of these problems.

According to a first aspect of the present invention, there is provided a chair having a back, a seat and a leg rest, the leg rest being mounted to the seat, wherein at least a feet-end of the leg rest can be folded and/or retracted below the seat to allow an occupant of the seat to place their feet on the floor beneath their centre of mass when standing, and/or to allow an occupant of the seat to place their feet on the floor at least partially beneath a front end portion of the seat.

According to a second aspect of the present invention, there is provided a chair having a back, a seat and a leg rest, the leg rest being mounted to the seat, wherein the leg rest can be folded and/or retracted to a position below the seat in which a forward-facing cushion surface of the folded and/or retracted leg rest is horizontally behind a front end of the seat, preferably by a distance of at least 5mm, more preferably by a distance of at least 25mm, most preferably by a distance of at least 50mm.

According to a third aspect of the present invention, there is provided a chair having a back, a seat and a leg rest, the leg rest being pivotally mounted to the seat by a hinge, wherein the hinge is retractable from a forward position at or near a front end of the seat to a retracted position beneath the seat.

Optional and preferred features are mentioned in the detailed description below and recited in the dependent claims.

Brief Description of the Drawings

To enable a better understanding of the present invention, 5 and to show how the same may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which:-Figure 1 shows a front perspective view of an intensive care 10 chair in a partially-reclined seated position; Figure 2 shows a front perspective view of the chair of Figure 1 in a fully reclined, bed-like configuration; Figure 3 shows a front perspective view of an occuhant being assisted to stand from a functionally equivalent chair to that shown in Figures 1 and 2; Figure 4 shows a side view of an embodiment of a leg rest 20 retraction mechanism for use in a chair according to the present invention; Figure 5 shows a side perspective view of the leg rest retraction mechanism of Figure 4 at its retracted oosition 25 and illustrating the forward sliding motion of the leg rest and hinge along the slide mechanism; Figure 6 shows a side perspective view of the leg rest retraction mechanism of Figures 4 and 5 illustrating the pivotal lifting motion of the leg rest about the hinge at its forward position; and Figure 7 shows a side view of a further embodiment of a leg rest retraction mechanism for use in a chair according to the 35 present invention.

Detailed Description

The invention will now be described with reference to specific embodiments. It is to be understood that the disclosed embodiments are provided in order to demonstrate one or more ways of putting the invention into effect and that they are in no way to be considered as being limiting on the scope of protection, which is defined solely by the appended claims.

Throughout the figures, like reference numerals are used to refer to like components.

Figures 1 and 2 show front perspective views of an intensive 15 care chair 100 respectively in a partially reclined, seated position and in a fully reclined, bed-like configuration.

The intensive care chair 100 is intended for use with critically ill and recovering patients, and so is configured not only to allow the patient to sit up, in the seated position shown in Figure 1, but also to allow the patient to be quickly put into a fully reclined recovery position, lying flat, with the chair 100 in the bed-like position as shown in Figure 2. Additionally, in order to aid in mobilisation, the chair 100 can be further operated to a more upright seating position, bringing the patient's feet down towards and in contact with the ground. The chair 100 will then assist the patient to stand by raising the seat 120 and by angling or tilting the seat 120 forward.

As shown in Figure 1, the chair includes a back 110, a seat 120 and a leg rest 130. The back 110 is pivotally coupled to the rear of the seat 120 via a hinge (not shown) so that the seat back can be moved between the lowered, substantially horizontal configuration shown in Figure 2 and a raised, seated configuration as shown in Figure 1. The seat back 110 can be further pivoted beyond the position shown in Figure 1 to a substantially upright position.

The leg rest 130 is pivotally coupled to a front end of the seat 120 at a hinge 125 (indicted, but not visible, in Figures 1 and 2). The leg rest 130 can be pivoted about the hinge 125 between a raised, substantially horizontal position as shown in Figure 2 and a lowered, seated position as shown in Figure 1. The leg rest 130 can be further pivoted about the hinge 125 beyond the position shown in Figure 1 to a fully lowered position in which it is substantially vertically aligned.

A foot rest 132 is provided at the feet end of the leg rest 130, and in this embodiment it is coupled to the leg rest 130 by a hinge 135. The footrest 132 can be pivoted around the hinge 135 so as to fold the footrest behind the leg rest 130. This allows the footrest 132 to support a patient's feet whilst they are seated in the chair 100, but to be displaced out of the way, in order to allow the patient to stand on the floor and not on the foot rest 132, when the leg rest 130 is fully lowered.

The chair 100 also includes wings 112 and 114 on the two sides of the back 110, as well as arms 122 and 124 on the two sides of the seat 120. In the upright, seated configuration of the chair 100, the wings 112, 114 and arms 122, 124 provide support to a patient in the chair 100 so that they can sit in comfort. They also serve to prevent the patient falling out of the chair when in an infirm condition and unable to support themselves reliably or at all. In the fully flat, bed-like position shown in Figure 2, the wings 112, 114 and the arms 122, 124 serve as sideboards to prevent a patient from rolling or otherwise falling out of the chair 100. The wings 112, 114 and arms 122, 124 are removable to facilitate sliding transfer of the patient from the chair 100 to an adjacent hospital bed or to a surgical table, when in the fully reclined bed-like configuration shown in Figure 2. They may alternatively be configure to be folded, rotated, slid or otherwise moved out of the way.

The seat 120 is mounted to a lifting means 160, for raising and lowering the seat 120 and the connected elements of the chair, including the back 110 and the leg rest 130. In Figure 1, the chair 100 is shown substantially in its fully lowered position. Lowering of the chair 100 is necessary to facilitate a patient sitting into and standing up from the chair 100, and the chair 100 is also more stable for accommodating a seated patient when in the lowered position.

By contrast, Figure 2 shows the chair 100 in a raised position, achieved by extending the lifting mechanism 160. In this position, a patient lying flat in the chair in its bed-like configuration is more easily accessible for nurses and medical staff to give treatment. Being able to adjust the height of the chair 100 also facilitates horizontal translation of the patient onto another adjacent surface at the same height, such as a hospital bed or operating table. In this example, the lifting means 160 is provided as a piston, such as a pneumatic piston, which can raise or lower the seat 120 simply by extending and retracting the piston.

Other lifting mechanisms could be used instead, such as a motorised lifting mechanism.

It will be appreciated that the raising and lowering of the chair back 110 and the leg rest 130 is also motorised, in this case using electric motors, although a piston mechanism would also be possible for the actuation of either or both of the chair back 110 and the leg rest 130.

Movement of the foot rest 132 about the hinge 135, as well as 35 movement or removal of the wings 112, 114 or the arms 122, 124 may be achieved either by manual operation or by way of a motorised or pneumatic system, depending on the model of the chair 100.

The lifting means 160 is mounted in a wheeled frame 150 having rear wheels 151, 152 and front wheels 153, 154. As best seen in Figure 2, the front end of the frame 150 is formed with forwardly projecting arms 155, 156, with the front wheels 153 and 154 mounted at the front ends thereof. This provides a separation between the front wheels 153 and 154 into which the leg rest 130 can be received when it is rotated around hinge 125 into its lowered position. The forward projection of the arms 155, 156 gives a wide lateral base to the wheeled frame 150 so as to make it stable and so prevent tilting or toppling when the chair 100 is in motion (i.e., when the chair is being wheeled around). In particular, the chair 100 must be stable when a patient is being wheeled somewhere with the chair 100 in the fully reclined, bed-like configuration shown in Figure 2.

Figure 3 shows an intensive care chair 100' which is functionally equivalent to the intensive care chair 100 shown in Figures 1 and 2. The chair 100' includes a back 110', a seat 120' and a leg rest 130'. The back 110' and the leg rest 130' are pivotably mounted to the respective back and front ends of the seat 120' in the same manner as the intensive care chair 100. Similarly, the seat 120' is mounted to a lifting means 160' in the form of a piston, with the lifting means 160' being mounted on a wheeled frame 150'. The wheeled frame 150' has rear wheels 151' and 152' and front wheels 153' (not visible in Figure 3) and 154'. As shown in Figure 3, the wings on the chair back 100' have been removed, whilst the arms 122' and 124' remain in place on each side of the seat 120'. The leg rest 130' is connected to the seat 120' by way of a hinge 125'. 3 5

Figure 3 illustrates how a patient P seated in the chair 100' is positioned when attempting to stand (or, in reverse, when sitting down into the chair 100'). A nurse N is shown controlling the seat 120' lifting and tilting mechanism to assist the patient P in standing. However, it can be seen that the patient P has their feet in front of their torso, and consequently in front of their body's centre of mass. Gravity is therefore is pulling the patient P into the chair, making it difficult or impossible for patient P to stand, and making the reverse process of sitting down into the chair difficult or unstable. The present invention seeks to beneficially facilitate the patient in positioning their feet beneath their body's centre of mass when standing up from an intensive care chair.

Turning to Figure 4, there is shown a leg rest retraction mechanism 200 for use in an intensive care chair, such as the intensive care chairs 100 and 100' described above. The mechanism shown is applied to the frame of a seat 220, and would replace the seat 120, hinge 125, leg rest 130 and foot rest 132 in the intensive care chair 100 or the corresponding seat 120', hinge 125' and leg rest 130' in the intensive care chair 100'.

The same mechanism is shown in Figures 4, 5 and 6, and the same reference numbers are used to refer to the same components. These figures show the framework of the mechanism 200, but without any cushions or padding applied to the seat 220, leg rest 230 or foot rest 232. It will be appreciated that these cushions or pads can simply be attached onto the respective components, in any known fashion. These and other components are not illustrated in Figures 4 to 6 in order to provide an unobstructed view of the main components of the leg rest retraction mechanism 200.

The leg rest retraction mechanism 200 is provided at the front end of the seat 220. Hinge parts 215 can be seen at the rear end of the seat 220 to provide a pivotable mounting point for the seat back.

In common with the previously described intensive care chairs 100 and 100', the present mechanism 200 provides for the leg rest 230 to be pivotably connected to the seat 220 via a hinge 225. However, in this case the hinge 225 is formed on or mounted to a slidable carriage 224, which is fixed beneath the seat 220. As best seen in Figures 5 and 6, the carriage 224 is slidable with respect to a so-called "frictionless" slide plate 222 made from a low friction material such as polypropylene, polyethylene, or medical grade nylon, as examples. The slide carriage 224 includes projecting portions which sit within and are guided by grooves formed in the slide plate 222, again as best seen in Figures 5 and 6.

Accordingly, the hinge 225 can be retracted from a forward position at or near the front end of the seat 220 to a retracted position as shown in Figure 4, where the hinge is beneath the seat 220, and in which it is retracted backwards behind the front end of the seat 220. In reverse, the hinge 225 can be translated forwards toward the front end of the seat 220 by sliding the carriage 224 forwards along the slide plate 222, until reaching the forward position shown in Figure 6.

Translation of the carriage 224 in the forwards and reverse directions is achieved by extending and retracting, respectively, a piston 270. A piston 270 is mounted to the seat 220 by way of a frame member 221 suspended beneath the seat 220. The rear end of the piston 270 is mounted to the frame member 221 by way of a pivotable coupling or hinge 272. The front end of the piston is not coupled directly to the carriage 224 but is coupled to a frame member 236 of the leg rest 230. Frame member 236 is pivotably connected to the carriage 224 at hinge 225, so as to allow the leg rest 230 to pivot between the lowered and raised positions relative to the seat 220. The front end of the piston 270 is coupled to the frame member 236 by a further pivotable coupling or hinge 274.

By virtue of this arrangement, the piston 270 is able to perform both the functions of translating the carriage 224 along the slide plate 220 (as shown by arrow A in Figure 5) and of rotating the leg rest 230 about the hinge 225 relative to the seat 220 (as shown by arrow B in Figure 6). This is achieved by mounting the piston 270 at an angle relative to the slide plate 222 so that, starting from the position shown in Figure 4 and 5, the force exerted by the piston 270 as it extends is converted solely into lateral, forward motion of the carriage 224 along the slide plate 222.

That is, as the piston 270 extends from the position shown in Figures 4 and 5, it will not cause rotation of the leg rest 230 about the hinge 225. This is achieved by a combination of the relative positioning of the pivot point 274 and hinge 225 relative to the position and angle of the piston, as well as accounting for the effects of friction and the weight of the leg rest 230. This arrangement ensures that the leg rest 230 will not rotate around the hinge 225 during the forward translation of the carriage 224 along the slide plate 222, until reaching the forward position of the carriage 224 as shown in Figure 6. At this position, forward translation of the carriage 224 is no longer possible, and continued extension of the piston 270 will cause the leg rest to pivot from its lowered position as shown in Figures 4 to 6 towards a raised position such as that of the leg rest 230 of chair 110 shown in Figures 1 and 2. The fully raised position of the leg rest 230 may be set to be that in which the leg rest 230 in a substantially horizontal alignment, i.e. in which the leg rest 130 and seat 220 are in a bed-like configuration such as shown for the chair 100 in Figure 2.

The same is true for the reverse motion, in which retraction of the piston 270 will firstly cause the leg rest 230 to rotate about the hinge 225 from a raised position (the reverse of arrow B shown in Figure 6), until the leg rest 230 reaches the fully lowered position shown in Figure 6 (and which is maintained in Figures 4 and 5). Further retraction of the piston 270 will then cause a sliding retraction of the carriage 224 along the slide plate 220 (the reverse of arrow A shown in Figure 5) to bring the carriage 224, as well as the hinge 235 and connected leg rest 230, back to the fully retracted position shown in Figures 4 and 5.

The sliding retraction and extension of the hinge 225 can thus be controlled independently from the pivoting of the leg rest 230 about the hinge 225, allowing a user of the chair to controllably adjust their position when seated in the chair and when resting their legs on the leg rest 230.

Leg rest 230 is additionally provided with a mechanism for extending and contracting the length of the leg rest 230, so as to make it longer or shorter between the hinge 225 and the hinge 235. This allows the intensive care chair to be lowered to a lower position than would otherwise be possible while still being able to retract the leg rest 230 beneath the seat 220.

The leg rest retraction mechanism 200 includes an outer tray 237, in which an inner tray 238 is slidably mounted so as to allow the inner tray to move inwardly and outwardly relative to the outer tray 237 in a sliding motion. The position of the inner tray 238 relative to the outer tray 237 can be fixed and secured by way of a threaded clamping means 239 which slides along a groove in the outer tray 237 as shown and is received in a threaded bore of the inner tray 238. The foot rest 232 is pivotably coupled to the inner tray 238 of the leg rest 230 at a hinged connection 235. It will be appreciated that the inner tray 238 and foot rest 232 are sized and configured to accommodate cushions or other padding, so as to make the leg rest 230 comfortable for a person seated in the chair. The foot rest 232 can also be made removable from the inner frame 238 in order to create additional space beneath the seat 220 when the leg rest 230 is retracted beneath the seat 220.

By virtue of the leg rest retraction mechanism 200, a space can be created beneath the front end of the seat 220 in which a patient or other occupant of the chair seated in the seat 220 can place their feet beneath their centre of mass when attempting to stand from the chair. This allows the patient or other occupant to stably take control of their body weight when standing, making it possible for infirm patients to stand when it would otherwise be impossible for them or they would be unstable.

It will be appreciated that the seat leg retraction mechanism 200 shown in Figures 4, 5 and 6 forms part of an intensive care chair which may otherwise have identical or equivalent construction to that of the chairs 100 and 100' shown Figures 1 to 3, such that the seat 220 is to be mounted on a lifting means for raising and lowering the seat, thus providing assistance to a patient or other occupant of the chair when standing.

The retractable leg rest 230 also beneficially allows the seat 220 to be brought to a lower position by the lifting means mounted in the wheeled frame of the intensive care chair, which makes it easier for patients of all shapes and sizes to place their feet firmly on the ground when still seated in the seat 220, prior to and at the point of standing.

A further embodiment of a leg rest retraction mechanism 200' is shown in Figure 7 in a view corresponding to that of Figure 4. Like components are designated by like reference numerals as for the embodiment of Figures 4 to 6 but supplemented by a prime "'fl. All descriptions made above for the embodiment of Figures 4 to 6 apply equally for the embodiment of Figure 7 and the corresponding components with corresponding reference numerals, unless clearly not applicable or explicitly stated otherwise herein.

Figure 7 shows a side view of leg rest retraction mechanism 200'. Unlike the "frame only" views in Figures 4 to 6, Figure 7 illustrates the seat back 210', seat 220' and leg rest 230' with cushions installed.

Seat back 210' is mounted on the hinges or hinge portions 215' (indicated but not visible in Figure 7) so as to be pivotably mounted to the seat 220'. The leg rest 230' is mounted to the hinge 225' carried by the carriage 224' and arranged to slide along a slide plate 222' (not visible in Figure 7) in identical manner as for the embodiment of Figures 4 to 6. Details of the slide mechanism of Figure 7 are the same in size, shape, form or function as compared with the embodiment of Figures 4 to 6, in particular as regards the frame member 221', piston 270', pivotable couplings 272' and 274' and leg rest frame member 236'.

In the embodiment of Figure 7, the leg rest 230' does not have an extendable length with sliding outer and inner trays, but is a fixed length. The leg rest 230' has a cushion mounted thereon, and, as shown in Figure 7, a face of the cushion (corresponding to the upper side of the cushion when the chair is in the bed-like configuration) faces forwards towards the front of the chair when the leg rest 230' is in its lowered and retracted position as illustrated.

The leg rest 230' has a foot rest 232' (not shown) that can be attached to and detached from the leg rest by way of any suitable attachment and release mechanism such as threaded connections or a sliding mechanism with a locking Din or nut. The foot rest 232' is removed in Figure 7.

The foot rest 232' will ordinarily be removed in a situation of use where the patient or other occupant of the chair wishes to stand. It is generally more stable to stand up onto the floor than onto the foot rest 232', and in some cases the foot rest 232' or its connection to the leg rest 230' is not strong enough to support the weight of a patient or other chair occupant standing on it.

What is clearly shown in Figure 7 is that a vertical line L at the front end of the seat 220' passes in front of the forward facing face of the cushion on leg rest 230'. That is, the front face of the cushion is retracted to a position behind the front end of the seat 220' by a horizontal distance D. In typical chair leg mechanisms, the leg rest hinge is located at the front end of the seat, so that the leg rest cushion projects forwards in front of the front end of the seat when the leg rest is folded down. Because of this an occupant of the chair cannot easily bend their leg around the front end of the seat when attempting to stand up. This forces the occupant to place their feet in front of the leg rest and in front of their centre of mass when attempting to stand, making standing difficult or impossible.

Bringing the front face of the cushion of the leg rest 230' behind the line L allows a patient or other chair occupant both to bend their knee more easily around the front end of seat 220' and also to position their feet under the front end of seat 220', allowing them to place their feet beneath their body's centre of mass when attempting to stand. More specifically, this arrangement allows an occupant of the seat to place their feet on the floor at least partially beneath a front end portion of the seat 220'. This assists with balance and weight distribution, making the process more stable.

The distance D can be as little as 0 mm while still obtaining some advantage over known designs in which the leg rest cushion projects in front of the front end of seat 220'. Greater advantage is achieved as the distance D increases, allowing the chair occupant to place their feet under the seat 220' and under their body's centre of mass. The distance D is therefore preferably at least 5mm, more preferably at least 25mm, and most preferably at least 50mm.

The same retraction of the front face of the cushion of the leg rest 230 and the attendant advantages are also present in and applicable to the embodiment of Figures 4 to 6 with the foot rest 232 removed.

Advantageously, the construction and arrangements shown in Figures 4 to 7 provide a single actuator for operating both the sliding and pivoting motions of the leg rest retraction mechanisms 200 and 200', minimising the number of components used in manufacture and assembly.

As well as reducing costs and complexity, this also reduces the amount of space occupied by the mechanism beneath the seat 220 or 220', which can become crowded by the various mechanisms that otherwise have to be accommodated in this space and which would otherwise stand in the way of allowing the leg rest 230 or 230' to be retracted beneath seat 220 or 220'. Notably, the underside of the seat has to accommodate motors or actuators for operating other components of the intensive care chair, such as the raising and lowering of the seat back about hinge 215 or 215', and in some cases additional motorised components such as for the arms or wings of the chair.

Many adaptations of the principles and concepts outlined above will be apparent to the skilled person in view of the teaching contained herein. All such variations within the scope of the appended claims and their equivalents as properly assessed are intended to fall within the scope of protection defined by the claims.

Claims

Claims 1. A chair having a back, a seat and a leg rest, the leg rest being mounted to the seat, wherein at least a feet-end of the leg rest can be folded and/or retracted below the seat to allow an occupant of the seat to place their feet on the floor beneath their centre of mass when standing, and/or to allow an occupant of the seat to place their feet on the floor at least partially beneath a front end portion of the seat.
2. A chair having a back, a seat and a leg rest, the leg rest being mounted to the seat, wherein the leg rest can be folded and/or retracted to a position below the seat in which a forward-facing cushion surface of the folded and/or retracted leg rest is positioned horizontally behind a front end of the seat, preferably by a distance of at least 5 mm, more preferably by a distance of at least 25 mm, most preferably by a distance of at least 50 mm.
3. A chair having a back, a seat and a leg rest, the leg rest being pivotally mounted to the seat by a hinge, wherein the hinge is retractable from a forward position at or near a front end of the seat to a retracted position beneath the seat.
4. The chair of Claim 3, wherein retraction of the hinge to the retracted position allows an occupant of the seat to place their feet on the floor beneath their centre of mass when standing.
S. The chair of Claim 3 or 4, wherein, with the hinge in the forward position, the leg rest is pivotable between a raised position, in which it may be substantially horizontally aligned, and a lowered position, in which it may be substantially vertically aligned.
6. The chair of Claim 5, wherein in the lowered position the leg rest is pivoted beyond the vertical so that the feet end of the leg rest is behind the hinged end.
7. The chair of Claim 5, 6 or 7, wherein the hinge is retractable when the leg rest is in the lowered position, and wherein the leg rest is arranged to be retracted together with the hinge.
8. The chair of any one of Claims 3 to 7, wherein the hinge is arranged to be retracted along a slide mechanism by a piston.
9. The chair of Claim 8, wherein the slide mechanism includes a slide plate made from polypropylene, polyethylene, medical grade nylon or another low friction material, and a slide carriage on which the hinge is arranged.
10. The chair of Claim 8 or 9, wherein the piston is also arranged to translate the hinge forward along the slide mechanism from the retracted position to the forward position.
11. The chair of Claim 8, 9 or 10 as dependent directly or indirectly on Claim 5, wherein the piston is further arranged to pivot the leg rest between the lowered and raised positions when the hinge is at the forward position.
12. The chair of any one of Claims 8 to 11, wherein the piston is mounted below the seat and is pivotally coupled at one end to the seat and is pivotably coupled at the other end to the leg rest.
13. The chair of any one of Claims 8 to 12, wherein the piston is pivotally coupled to the seat and the leg rest at an angle relative to the slide mechanism and with the pivot points arranged relative to the hinge such that, when the piston extends to translate the hinge forwards along the slide mechanism from the retracted position, the leg rest remains in the lowered position until the hinge reaches the forward position, at which point further extension of the piston pivots the leg rest from the lowered position towards the raised position.
14 The chair of Claim 13, wherein the pivot points are further arranged relative to the hinge such that, when the hinge is in the forward position, when the piston retracts to lower the leg rest from the raised position to the lowered position, it will not retract the hinge along the slide mechanism until the leg rest reaches the lowered position, at which point further retraction of the piston slides the hinge along the slide mechanism from the forward position towards the retracted position.
15. The chair of any preceding claim, wherein the chair is an assisted standing chair and the seat is arranged to raise and/or tilt forward to assist an occupant seated in the chair to stand.
16. The chair of any preceding claim, wherein a length of the leg rest can be reduced by sliding or folding a feet-end portion of the leg rest into or under a hinge-end portion of the leg rest.
17. The chair of any preceding claim, wherein the seat is mounted to a lifting means for raising and lowering the seat.
18. The chair of Claim 18, wherein the lifting means is mounted in a wheeled frame.
19. The chair of Claim 18, wherein left and right front wheels of the wheeled frame are mounted on respective left and right mounting arms, and at least a feet end of the leg rest is arranged to be accommodated in a space between the mounting arms when the hinge is retracted.
20. The chair of any preceding claim, wherein the chair back is pivotable relative to the seat between a lowered position, in which it may be substantially horizontally aligned, and a raised position, in which it may be substantially vertically aligned
21. The chair of any preceding claim, wherein the chair is an intensive care chair or a trauma chair