GB1583906A

GB1583906A - Leg support arrangements

Info

Publication number: GB1583906A
Application number: GB41096/77A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-05-15
Filing date: 1978-05-15
Publication date: 1981-02-04

Description

(54) IMPROVEMENTS IN OR RELATING TO LEG SUPPORT ARRANGEMENTS (71) I, WILLIAM CORDINGLEY ALLEN, a British subject, of 68, High Street, Lenham, Kent ME17 2QB, do hereby declare the invention for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement : The present invention relates to leg support arrangements and in particular to leg supports for use by disabled persons and intended for attachment to chairs or other seats.

Leg supports in the form of flaps to be attached to the front edges of chairs are known. Such flaps are often attached after the chair users are occupying the chairs and are hooked or clamped in position while the users legs are supported by a helper. Flaps of this kind can only be repositioned with the aid of a helper.

The present invention is concerned with an arrangement for attachment to chairs and in particular to wheelchairs to allow a disabled user with the ability to move his upper limbs to adjust the leg support in order to improve the comfort of his chair and also, in suitable cases, to complete unaided a transfer from the chair to a bed or settee, for example.

According to the present invention, a leg support arrangement for a seat useable by a disabled person, includes a main support arranged for attachment at the front edge of the seat; a leg support member hinged at one edge to the main support member and moveable between a fully lowered position in which in use the member hangs from the seat edge and a fully raised position in which it lies in a position to act as a continuation of the seat; means for moving the leg support member comprising a gear arrangement having an input shaft and an output having an extending lever turned about a pivot in response to rotation of the input shaft, the gear arrangement also including ratchet means for preventing movement of the lever in response to a load thereon; means for mounting the gear arrangement on the main support; means for securing a roller assembly for rotation to the extending lever, the 'lever extension being such as to bring the roller assembly out from the seat when the arrangement is in use to engage the underside of the leg support member; and means for rotating the input shaft to move the leg support member. The rotating means may simply be a manually operable handle or it may include a motor connected to drive the input shaft.

A wheelchair embodying the present invention will now be described, by way of example, with reference to the accompanying drawing, in which, Figure 1 is a side view of a wheelchair having an adjustable leg support, Figure 2 is a view of the underside of the wheelchair, and, Figure 3 is a partial side view of a modified leg support. Referring to Figures 1 and 2, a wheelchair 1 of conventional form has a seat 2 carried by a pair of side-frame members 3. A support 4 is fitted across the underside of the front edge of the seat 2 and is clamped in this position by, for example, U-clamps 5 to the members 3. A hinge 6 is attached to the front of the support 4 and a leg support flap 7 is attached to the hinge 6, so that the flap 7 is free to move between an almost vertical position 8 and a substantially horizontal position 9 indicated by dashed lines in the Figure.

A flap raising arrangement is secured by a bracket 10 to the underside of the support 4. The arrangement has an arm 11 attached to a semicircular toothed plate 12 which is pivoted at 13 to a side plate of a gearbox 14. The gearbox 14 has an input spindle 15 formed as an extension piece to an input stub at the gearbox 14, and the spindle 15 is supported in a bearing plate 16 clamped to the frame of the chair 1. The spindle 15 carries a crank-handle 17, the spindle 15 being sufficiently long to permit the crankhandle 17 to extend beyond the side frame of the chair 1 to within reach of an occupant of the chair 1. The arm 11 has an extension piece 18 which carries a trans verse tube 19 housing a spindle 20.

The spindle 20 carries a pair of rollers 21 arranged to run on a spaced pair of tracks 22 secured to the underside of the flap 7. The tracks 22 may each be simply L-shaped members secured by one arm of the L to the flap so that the track 22 is formed by the other arm, and in this case, each roller 21 is grooved to accept the track profile. Alternative forms may be used for the tracks 22, such as rods of circular cross section, and in this case the rollers 21 would have a concave profile to suit that of the tracks 22.

It will be seen that as the arm 11 is rotated with the toothed plate 12 about the pivot 13, this movement is applied through the rollers 21 to raise the flap 7. The gearbox 14 is arranged to rotate the plate 12 in response to rotation of the input spindle 15 by the crank-handle 17. Not only is the gearbox 14 arranged to provide a lowgeared input to secure a mechanical advantage sufficient to lift the flap 7 while it is supporting the users legs, but it also has a double action ratchet mechanism on the plate 12 so that the flap 7 will remain in the position in which it was last set, regardless of whether it was being raised or lowered.

Such a gearbox is readily commercially available as an accessory in the motor vehicle industry and is used to operate an arm for raising and lowering a window of a motor vehicle. In the present arrangement such a window control was used simply by the addition of the bracket 10 to permit the gearbox to be mounted on the support 4, and the further addition of the extension lever 18 carrying the rollers 21.

It will be realised that the flap 7 may be lifted manually so that the tracks 22 are taken out of contact with the rollers 21.

This is of no consequence where, for example, flat tracks 22 are used in conjunction with plain rollers 21. Where, however, the tracks 22 are narrow and the rollers 22 are grooved to receive them, it is usually undesirable that they should be separated and in this case a keeper plate may be provided as indicated by a dashed outline in Figure 2. Figure 3 shows the keeper plate 23 in greater detail and it will be seen that the plate 23 has an upstanding portion with a slot 24 extending along its length.

The tube 19 supporting the roller spindle 20 passes through the plate 23 in the slot 24 so that the rollers 21 are prevented from disengaging from the tracks 22.

In use it is intended that a chair user will be enabled to raise the flap 7 by the use of the hand-crank 17 to raise his legs to a horizontal position before wheeling the chair alongside a bed, settee or other article of furniture to which he wishes to transfer. The arm rest of the chair is swung away, this being a feature of such chairs for the use of the disabled. The user then manoeuvres the upper part of his body from the chair seat to the furniture article while his legs remain supported on the flap 7. Finally, he moves his legs from the flap on to the furniture article.

It is found that some disabled users are able to perform this action without assistance. However, even when the user is unable so to do, it will be realised that the ability to control the angle of the flap 7 by a simple control is still an advantage.

Although shown as a single flat platform, it will be realised that the flap 7 may be padded or profiled as may be required.

The flap 7 and its operating arrangements are readily fitted to conventional wheelchairs by clamps, so that the arrangement is particularly valuable as an attachment for use in suitable cases. However, it may also be incorporated as an integral part of a special purpose chair. The arrangement is also readily fitted to a wheel chair equipped with individual footboards, the flap 7 moving between the footboards when they are in their raised positions. It is also possible to fit the arrangement to other seats than those of invalid chairs. Thus, an arrangement of suitable proportions may be fitted to a conventional household chair or bench as an adjustable leg rest.

A further improvement (not shown) consists in the addition of a low-voltage reversible motor connected to the gearbox, for example by a stepped down drive coupling, such as an adidtional gear train. The motor is conveniently driven from a battery carried on a support, arranged for example, behind or beneath the seat, by means of a switching arrangement contained in a box within easy reach of the occupant of the chair. The addition of the motor drive renders the benefits of the adjustable leg support available to a disabled occupant of the chair who has insufficient strength to operate the crank-handle described above.

The battery preferably consists of secondary cells.

WHAT I CLAIM IS:- 1. A leg support arrangement for a seat useable by a disabled person, including a main support arranged for attachment at the front edge of the seat; a leg support member hinged at one edge to the main support and moveable between a fully lowered position in which in use the member hangs from the seat edge and a fully raised position in which it lies in a position to act as a continuation of the seat; means for moving the leg support member comprising a gear arrangement having an input shaft and an output having an extending lever turned about a pivot in response to

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. verse tube 19 housing a spindle 20. The spindle 20 carries a pair of rollers 21 arranged to run on a spaced pair of tracks 22 secured to the underside of the flap 7. The tracks 22 may each be simply L-shaped members secured by one arm of the L to the flap so that the track 22 is formed by the other arm, and in this case, each roller 21 is grooved to accept the track profile. Alternative forms may be used for the tracks 22, such as rods of circular cross section, and in this case the rollers 21 would have a concave profile to suit that of the tracks 22. It will be seen that as the arm 11 is rotated with the toothed plate 12 about the pivot 13, this movement is applied through the rollers 21 to raise the flap 7. The gearbox 14 is arranged to rotate the plate 12 in response to rotation of the input spindle 15 by the crank-handle 17. Not only is the gearbox 14 arranged to provide a lowgeared input to secure a mechanical advantage sufficient to lift the flap 7 while it is supporting the users legs, but it also has a double action ratchet mechanism on the plate 12 so that the flap 7 will remain in the position in which it was last set, regardless of whether it was being raised or lowered. Such a gearbox is readily commercially available as an accessory in the motor vehicle industry and is used to operate an arm for raising and lowering a window of a motor vehicle. In the present arrangement such a window control was used simply by the addition of the bracket 10 to permit the gearbox to be mounted on the support 4, and the further addition of the extension lever 18 carrying the rollers 21. It will be realised that the flap 7 may be lifted manually so that the tracks 22 are taken out of contact with the rollers 21. This is of no consequence where, for example, flat tracks 22 are used in conjunction with plain rollers 21. Where, however, the tracks 22 are narrow and the rollers 22 are grooved to receive them, it is usually undesirable that they should be separated and in this case a keeper plate may be provided as indicated by a dashed outline in Figure 2. Figure 3 shows the keeper plate 23 in greater detail and it will be seen that the plate 23 has an upstanding portion with a slot 24 extending along its length. The tube 19 supporting the roller spindle 20 passes through the plate 23 in the slot 24 so that the rollers 21 are prevented from disengaging from the tracks 22. In use it is intended that a chair user will be enabled to raise the flap 7 by the use of the hand-crank 17 to raise his legs to a horizontal position before wheeling the chair alongside a bed, settee or other article of furniture to which he wishes to transfer. The arm rest of the chair is swung away, this being a feature of such chairs for the use of the disabled. The user then manoeuvres the upper part of his body from the chair seat to the furniture article while his legs remain supported on the flap 7. Finally, he moves his legs from the flap on to the furniture article. It is found that some disabled users are able to perform this action without assistance. However, even when the user is unable so to do, it will be realised that the ability to control the angle of the flap 7 by a simple control is still an advantage. Although shown as a single flat platform, it will be realised that the flap 7 may be padded or profiled as may be required. The flap 7 and its operating arrangements are readily fitted to conventional wheelchairs by clamps, so that the arrangement is particularly valuable as an attachment for use in suitable cases. However, it may also be incorporated as an integral part of a special purpose chair. The arrangement is also readily fitted to a wheel chair equipped with individual footboards, the flap 7 moving between the footboards when they are in their raised positions. It is also possible to fit the arrangement to other seats than those of invalid chairs. Thus, an arrangement of suitable proportions may be fitted to a conventional household chair or bench as an adjustable leg rest. A further improvement (not shown) consists in the addition of a low-voltage reversible motor connected to the gearbox, for example by a stepped down drive coupling, such as an adidtional gear train. The motor is conveniently driven from a battery carried on a support, arranged for example, behind or beneath the seat, by means of a switching arrangement contained in a box within easy reach of the occupant of the chair. The addition of the motor drive renders the benefits of the adjustable leg support available to a disabled occupant of the chair who has insufficient strength to operate the crank-handle described above. The battery preferably consists of secondary cells. WHAT I CLAIM IS:-

1. A leg support arrangement for a seat useable by a disabled person, including a main support arranged for attachment at the front edge of the seat; a leg support member hinged at one edge to the main support and moveable between a fully lowered position in which in use the member hangs from the seat edge and a fully raised position in which it lies in a position to act as a continuation of the seat; means for moving the leg support member comprising a gear arrangement having an input shaft and an output having an extending lever turned about a pivot in response to

rotation of the input shaft, the gear arrangement also including ratchet means for preventing movement of the lever in response to a load thereon; means for mounting the gear arrangement on the main support; means for securing a roller assembly for rotation to the extending lever, the lever extension being such as to bring the roller assembly out from the seat to which the arrangement is attached in use to engage the underside of the leg support member; and means for rotating the input shaft to move the leg support member.

2. A leg support arrangement as claimed in Claim 1, in which the rotating means includes a manually operable handle attached to the input shaft.

3. A leg support arrangement as claimed in Claim 2, in which the gear arrangement includes a low gear connection to the extending lever whereby a mechanical advantage is produced to permit a significantly small effort applied to the handle to raise the leg support member when loaded by the legs of an occupant of the seat to which the arrangement is attached in use.

4. A leg support arrangement as claimed in any preceding claim, in which the main support member is attachable to the seat by readily disengageable clamps.

5. A leg support arrangement as Claimed in Claim 4, in which the input shaft is supported in a bearing arranged to be clamped to the structure of the seat on which it is to be used to permit the handle to extend beyond the side of the structure.

6. A leg support arrangement as claimed in Claim 1, including a track arrangement mounted on the underside of the leg support member, the roller assembly being brought into engagement with the track arrangement by the lever extension.

7. A leg support arrangement as claimed in Claim 6, in which the track arrangement consists of a pair of spaced parallel track members extending at right-angles to the hinge and in which the roller assembly consists of a pair of rollers spaced apart to enable the rollers each to engage a different track member.

8. A leg support arrangement as claimed in Claim 7, in which the peripheries of the rollers are shaped to conform to the profiles of the track members.

9. A leg support arrangement as claimed in Claim 7 or Claim 8 in which the rollers are mounted on a common spindle and in which a slotted keeper plate is provided parallel to the tracks, the spindle moving in the slot of the keeper plate as the rollers move along the tracks to maintain the rollers in engagement with their respective tracks.

10. A leg support arrangement as claimed in Claim 1, in which the rotating means includes an electric motor connected to drive the input shaft and switching means connected to the motor and to a source of electric energy.

11. A leg support arrangement for a seat useable by a disabled person, constructed and arranged to operate substantially as described with reference to Figures 1 and 2, or to Figures 1, 2 and 3 of the accompanying drawing.