GB2330299A

GB2330299A - Leg support for wheelchair

Info

Publication number: GB2330299A
Application number: GB9721127A
Authority: GB
Inventors: Donald Brookes
Original assignee: MEDEQUIP SUB 1 Ltd; Sunrise Medical Ltd; Parker Bath Ltd
Current assignee: MEDEQUIP SUB 1 Ltd; Sunrise Medical Ltd; Parker Bath Ltd
Priority date: 1997-10-07
Filing date: 1997-10-07
Publication date: 1999-04-21
Anticipated expiration: 2017-10-07
Also published as: GB9721127D0; GB2330299B

Abstract

An elevating leg support for a wheelchair includes a leg support 10 pivoted at 27 to a link 12 which is itself pivoted at 28 to a mounting member 11 on the wheelchair. A pivotal control link 13 is so connected to the mounting member and leg support that when the support is moved from the lowered towards a horizontal position (arrow A), the pivot point 27 moves forward (arrow B) thereby increasing the effective length of the leg support. The link 13 may be replaced by another link of a different length or may itself be adjustable in length. Movement may be driven by a telescopically extending electrically powered screw and nut mechanism 14.

Description

Title: LEG SUPPORT FOR WHEELCHAIR Description of Invention This invention relates to a leg support for a wheelchair, and more particularly to a so-called elevating leg support.

An elevating leg support is movable relative to the main structure of a wheelchair between a lowered position in which it is able to support a leg of the occupant of the wheelchair in a position in which it extends downwardly from the knee, usually with the occupant's foot supported on a foot rest at or adjacent the lowermost end of the leg support, and an elevated position in which it is able to support the leg of the occupant extending more or less horizontally forward from the knee, usually with the weight of the occupant's lower leg supported by a support member beneath the occupant's calf. In the simplest arrangement, the leg support is mounted to the structure of the wheelchair by a simple pivotal mounting which is at or adjacent the uppermost end of the leg support when the leg support is in its lowered position.

However, in known wheelchairs it is most unlikely that the axis about which such a leg support pivots will coincide with the pivot axis of the knee of the wheelchair's occupant. Usually the relationship between such axes is such that as the leg support is moved to its elevated position the footrest will tend to push on the underside of the occupant's foot, forcing the occupant backwardly in the seat of the wheelchair. This is undesirable. It has been proposed that this problem can be overcome if the leg support is designed as a telescopic structure and there is provided a means for extending it telescopically as it is moved from its lowered position to its elevated position.

Such telescopic extension of the leg support is in addition to any telescopic or otherwise adjustment of the length of the leg support which is able to be pre-set to suit different sizes of wheelchair occupant. However, the mechanisms proposed for causing such telescopic extension of a leg support have been complex and hence expensive to manufacture and potentially unreliable.

It is broadly the object of the present invention to provide an improved elevating leg support for a wheelchair.

According to one aspect of the invention, we provide an elevating leg support for a wheelchair, comprising a leg support member; a mounting member adapted for connection to the wheelchair; a link member having a first pivotal connection to said leg support member and a second pivotal connection to said mounting member at a position spaced from said first pivotal connection; said first pivotal connection providing for pivotal movement of the leg support member between a lowered position in which it extends generally dossnsvardly from said first pivotal connection and an elevated position in which it extends generally forwardly from said first pivotal connection; and control means operable to cause pivotal movement of the link member about said second pivotal connection as the leg support member moves from its lowered position to its elevated position, so that said first pivotal connection and leg support member are displaced forwardly in the course of said movement.

Preferably the control means comprises a control member which is pivotally connected on the one hand to the mounting member and on the other hand to the leg support member.

By appropriate selection of the length of the control member, the amount by which the link member pivots about its second pivotal connection in the course of movement of the leg support member from its lowered position to its elevated position, and hence the amount by which the leg support member is displaced fornvardln in the course of such movement, can be varied. It is envisaged that a number of control members of different lengths would be available, or a control member of adjustable length could be utilised to enable the leg support to be adapted for different models of wheelchair and/or different wheelchair occupants.

The invention is applicable to a leg support which is moved manually between its lowered and elevated positions. Preferably, however, there is powered actuating means for causing such movement.

Such a powered actuating means may comprise an electrically powered actuator, conveniently of telescopically-extendable form. Such an actuator may be pivotally connected between the link member adjacent its pivotal connection to the mounting member, and the leg support member at a position spaced from the pivotal connection of the leg support member to the link member.

The invention also provides a wheelchair having an elevating leg support in accordance with the first aspect of the invention.

The invention will now be described by way of example with reference to the accompanying drawings, of which: Figure 1 is a side elevation of an elevating leg support in accordance with the invention, in a first operative position; Figure 2 is a view as Figure 1 but with the leg support in a second position.

Referring firstly to Figure 1 of the drawings, an elevating leg support comprises the principal components of a leg support member indicated generally at 10, a mounting member 11, a link member 12, a control member 13, and an actuator 14.

The leg support member 10 comprises a tubular upper portion 15 and a lower portion 16 which is telescopically adjustable relative to the upper portion 15 and is able to have its adjusted position fixed, e.g. bs a clamping device, not shown. Thus the overall length of the leg support member can be set as required to suit a particular wheelchair occupant. At its lowermost end, the portion 16 of the leg support member carries a footrest 17. Approximately mid-way up the leg support member, it may carry a support part such as a concave pad for supporting the calf of the wheelchair occupant.

The mounting member indicated generally at 11 comprises an upwardly oriented tubular member 20 which towards its upper end has secured thereto a rearwardly extending arm 21 which in turn carries a spigot 22 protruding downwardly for reception in the open top of a frame tube 23 of a wheelchair. At its lowermost end the mounting member 20 carries a bracket 24 and a clip 25 which is of an appropriate design to engage the external surface of the frame tube 23. Thus the mounting member 20 is removably connected to the wheelchair. The forward end of a seat cushion of the wheelchair is indicated at 44, and a support tube therefor is shown at 45.

The link member 12 has a first pivotal connection by a clevis and pivot pin arrangement indicated at 27 to the top end of the leg support member 10. The link member further has a second pivotal connection as indicated at 28 to the top of the mounting member 11.

The control member 13 comprises a link which is pivotally connected at 29 to a bracket 30 welded to the part 15 of the leg support member 10 adjacent its top end. The opposite end of the control link member 30 is pivotally connected at 3 1 to a bracket 32 adjacent the lowermost end of the mounting member 20.

The actuator indicated generally at 14 is a Wlescopically extendable and contractable device of the tqlpe incorporating an electric motor and a screw and nut mechanism. Its body portion 34 in which the electric motor is housed is pivotally connected at 35 to the link member 12 adjacent the second pivotal connection 28 of such link member to the mounting member 20. The actuator further comprises a tubular extension 36 of the body 34 and an output member 37 extends from the open end of the portion 36. The output member 37 is pivotally connected at 38 to a bracket 39 embracing the part 15 of the leg support member.

Figure 1 shows the leg support in a lowered position in which it extends downwardly from its pivotal connection 27. Extension of the actuator 14 causes it to be moved to an elevated position and Figure 2 shows the leg support in such a position in which it extends forwardly and nearly horizontally from its pivotal connection 27. To reach this position, the leg support 10 has moved in a generally arcuate path of movement as indicated by the arrow A on Figure 1, while the link member 12 has also moved in an arcuate path about its pivotal connection 28, as indicated by the arrow B in Figure 1. Such arcuate movement of the link member 12 from a position in which it is upwardly inclined at about 45" to the horizontal from its pivotal connection 28 to a position in which it lies closer to the horizontal, causes the leg support member as a whole to be moved forwardly away from the mounting member 20.

The extent of such movement of the leg support member is determined by the geometry of the pivotally connected components of the leg support assembly. In particular, a change in the length of the control link member 13 will cause a change in the amount by which the leg support is moved folwvardly as it is moved to its elevated position, and accordingly replacement of the control link member 13 by another one of different length may be carried out in order to suit the elevating leg support assembly to a different wheelchair and/or occupant. A further altelTnative is that a control link member 13 of adjustable length may be utilised. For example. a control link member could be provided with a number of apertures spaced along its length. with appropriate ones being selected to be used for the pivotal connections to the mounting member and leg support member. Alternativelss a control link member could comprise separate parts adapted to be connected respectively to the mounting member and leg support member, which parts are adjustable relative to one another and able to be fixed in a relative position that sets the two pivotal connections of the control link member at the required distance from one another.

Thus the invention provides an elevating leg support assembly which in straightforward manner overcomes or reduces the above described disadvantages associated with previously known such leg supports.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

CLAIMS 1. An elevating leg support for a wheelchair, comprising a leg support member; a mounting member adapted for connection to the wheelchair; a link member having a first pivotal connection to said leg support member and a second pivotal connection to said mounting member at a position spaced from said first pivotal connection; said first pivotal connection providing for pivotal movement of the leg support member between a lowered position in which it extends generally downwardly from said first pivotal connection and an elevated position in which it extends generally forwardly from said first pivotal connection; and control means operable to cause pivotal movement of the link member about said second pivotal connection as the leg support member moves from its lowered position to its elevated position, so that said first pivotal connection and leg support member are displaced forwardly in the course of said movement.
2. A leg support according to Claim 1, wherein the control means comprises a control member which is pivotally connected on the one hand to the mounting member and on the other hand to the leg support member.
3. A leg support according to Claim 2, wliereiii the control member is adapted to be replaced by an alternative control member of different length.
4. A leg support according to Claim 2, wherein the control member is adjustable in length.
5. A leg support according to any one of preceding claims, wherein there is powered actuating means for causing movement of the leg support between its lowered and elevated positions.
6. A leg support according to Claim 5, wherein said powered actuating means comprises an electrically powered actuator of telescopically-extendable form.
7. A leg support according to Claim 6, wherein said actuator is pivotally connected between the link member adjacent its pivotal connection to the mounting member, and the leg support member at a position spaced from the pivotal connection of the leg support member to the link member.
8. A leg support substantially as hereinbefore described with reference to the accompanying drawings.
9. A wheelchair having an elevating leg support according to any one of the preceding claims.
10. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.