GB2278090A

GB2278090A - Powered mobility aid for a standing person.

Info

Publication number: GB2278090A
Application number: GB9324382A
Authority: GB
Inventors: Robin Banks
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-05-22
Filing date: 1993-11-26
Publication date: 1994-11-23
Also published as: GB9310576D0; GB9324382D0

Abstract

A mobility aid for use by the disabled or infirm comprises a wheeled platform (10) on which the user of the aid can stand. At the front of the platform (10), there is a framework (14) on the top of which are mounted control means (15) for controlling operation of motors which drive the front wheels (11) of the aid. Apart from the framework (14), the platform (10) is substantially unenclosed so that the user of the aid can obtain access to the platform (10) from the rear and both sides. <IMAGE>

Description

MOBILITY AIDS Field of the Invention This invention relates to mobility aids, i.e. to equipment for use by the disabled or infirm to enable them to achieve an increased degree of mobility.

There are at present a range of motorised vehicles for use by the disabled but they have the disadvantage that their size limits the situations in which they can be used. Their cost also limits their availability.

There are also motorised wheelchairs; but there are many partially disabled people whose disabilities are such that they do not wish to become "confined" to a wheelchair.

It has accordingly been proposed in US Patent Specification No. 3,872,945 to provide a powered walker for use by disabled persons in a standing position within the walker which comprises a four-sided frame extending vertically upward from a platform. The platform is supported by a pair of front wheels, one of which is driven by an electric motor, and by a pair of rear wheels which can be turned for steering the vehicle. The four-sided frame effectively encloses the user of the walker so as to support the user in a standing position.

The powered walker is, as mentioned in the specification, liable to tip and is really only suitable for use over flat, even surfaces. It is also not really suitable for use by persons whose only disability is a "walking" disability.

A further powered walker is disclosed in US Patent Specification No. 5,168,947 and includes a wheeled platform upon which a person can stand. Variable speed reversible electric motors are provided for driving the wheels and a three-sided walker frame, within which a person can stand, is detachably mounted on the platform. The walker frame includes control switches for separately and independently controlling the two motors.

The electric motors drive the rear wheels of the platform so that it is liable to tip in a rearward direction. The threesided frame again encloses the user of the walker, though not to the same extent as the frame of the walker of US Specification No. 3,872,945 and, once more, the walker is really only suitable for use over flat, even surfaces.

It is accordingly an object of the present invention to provide an improved mobility aid which is not limited to use over flat, even surfaces.

It is a further object of the invention to provide a stable motorised mobility aid which does not have a "confining" effect on the user of the aid.

It is a still further object of the invention to provide a motorised mobility aid for use by the partially disabled, for example, by people in the early stages of Parkinson's disease.

Summary of the Invention According to the present invention there is provided a mobility aid comprising a platform on which the user of the aid can stand, a power source mounted on the platform, a plurality of ground-engaging wheels supporting the platform, said wheels including a pair of independently driven front wheels and one or more rear wheels, an upwardly extending structure at the front of the platform which is otherwise substantially unenclosed so as to permit the user to obtain access to the platform from the rear thereof or from either side, and control means mounted at or adjacent the top of the upwardly extending structure whereby the user can control the direction and rate of movement of the platform.

The platform is preferably a substantially rectangular platform and there are preferably two rear wheels, preferably castor wheels, the four wheels supporting the platform being disposed at the four corners of the rectangle so as to provide a stable supporting structure.

The driven front wheels are preferably of larger diameter than the rear castor wheels and the driven front wheels are preferably arranged for rotation about axes which are above the level of the platform support surface so as, again, to increase the stability of the mobility aid.

The power source may be an internal combustion engine which drives a pump which supplies hydraulic fluid under pressure to reversible hydraulic motors which drive the front wheels. The control means may then be in the form of a pair of pivoted levers mounted at the top of the upwardly extending structure at the front of the platform, the two levers being pivotable inwardly, i.e. towards one another, to effect forward driving movement of the hydraulic motors and pivotable outwardly, i.e. away from one another, to effect rearward driving movement of the hydraulic motors. If it is desired to turn the platform with a very small turning circle, one of the drive wheels will be driven in the forward direction while the other drive wheel is being driven in a rearward direction.

The power source may alternatively be an electric battery or battery pack, particularly one or more rechargeable batteries. The motors driving the drive wheels will then be reversible electric motors and the control means may then be in the form of a pair of switches mounted at the top of the upwardly structure at the front of the platform, one switch being moved to control the direction and rate of rotation of one of the drive wheels and the other being moved to control the rate of rotation of the other drive wheel.

The power source is preferably positioned on the platform so that its centre of gravity is substantially on the front-toback centre-line of the platform and is spaced a significant distance to the rear of the axles of the front wheels. A stable structure will thus be obtained enabling the mobility aid to be used over uneven or inclined surfaces.

A front frame member may extend from side-to-side of the mobility aid forwardly of the supporting surface of the platform, the drive wheels being mounted on the front frame member by means of stub axles.

In a modification of the arrangement defined above, a four-wheel-drive system is provided. For example, the two driven front wheels may be connected by belt or chain drives to corresponding rear wheels. The likelihood of slipping of the wheels when the aid is being driven over, for example, muddy ground, would thereby be reduced.

In a further modification of the arrangement defined above, the four wheels are replaced by a pair of tracks, one on each side of the vehicle and independently driven, as described above, by, for example, hydraulic motors.

Brief Description of the Drawings Figure 1 is a side view of a mobility aid, Figure 2 is a front view of the mobility aid, and Figure 3 is a plan view of the mobility aid.

Description of the Preferred Embodiment The mobility aid illustrated schematically in the accompanying drawings includes a generally rectangular platform 10 on which the user of the aid will stand. The platform 10 has a pair of front wheels 11 and a pair of rear wheels 12 disposed (as shown in Figure 3) at the four corners of the rectangle.

The front wheels 11 are driven wheels and are of larger diameter than the rear wheels 12 which are castor wheels. The platform 10 is supported between the wheels and, as can be seen from Figure 1, the level of the supporting surface of the platform 10 is below the level of the axes of the front wheels 11. This enhances the stability of the aid.

A power source is mounted on the platform 10. The power source is illustrated diagrammatically by the block 13 shown in the drawings. The power source 13 can be an internal combustion engine which drives a hydraulic pump which supplied hydraulic fluid under pressure to reversible hydraulic motors which drive the two front wheels 11.

A support structure, in the form of a framework 14, extends upwardly from the front of the platform 10 and, as can be seen from Figure 1, the framework 14 is inclined rearwardly.

At the top of the framework 14, there are a pair of control levers 15 which control operation of the hydraulic motors driving the front wheels 11. The levers 15 are connected by links 16 to control members of the hydraulic motors and the arrangement is such that the right-hand side lever 15 controls operation of the right-hand side front wheel 11 while the lefthand side lever 15 controls the left-hand side front wheel 11.

When the respective control lever 15 is moved inwardly from its 'at rest' position, the corresponding wheel 11 is driven forwardly at a rate dependent on the angle through which the lever 15 has been pivoted while, when one of the control levers 15 is pivoted outwardly, the corresponding front wheel 11 is driven rearwardly, again at a rate dependent on the angle through which the lever 15 has been pivoted.

The hydraulic system may be such that the aid can be driven at a speed of the order of 6 or 7 kilometres per hour, i.e. at a brisk walking speed and the power of the engine and hydraulic system may such that the aid is able to ascend significant inclines when carrying a typical adult male and/or to be driven over rough terrain.

The framework 14 at the front of the platform 10 acts as a support for the user of the aid and it is to be noted that the platform 10 is unenclosed at the rear and at the sides.

This means that the user of the aid can obtain access to the platform 10 from either side or from the rear. He or she does not feel hemmed in and, if physically fit apart from his or her walking disability, is able to carry out a variety of 'normal' activities.

The engine and hydraulic system are positioned so that their centre of gravity is on the front-to-back centre-line of the platform 10 and so that their centre of gravity is to the rear of the axes of the front wheels 11 (as shown in Figure 1).

The front wheels 11 can be mounted by means of stub axles on a front frame member 17 which acts as a structural element of the aid and is located forwardly of the platform 10. This whole arrangement (including the front-wheel drive arrangement) ensures the maximum stability for the aid enabling it be used over rough terrain and uneven ground, such as might be encountered by a farmer or shepherd.

As mentioned above, the power source may be one or more rechargeable batteries mounted on the platform 10 and providing an electrical supply to reversible electric motors which drive the front wheels 11.

It will be seen from the above that the invention provides a mobility aid which has a variety of uses and is more versatile than the prior art devices referred to above. As mentioned above, a four-wheel-drive version of the mobility aid may be provided. The front and rear wheels may also be replaced by tracks.

As illustrated, the rear wheels 12 may be standard castor wheels. Each rear wheel may, however, be in the form of a sphere slightly less than half of which projects from a housing within which a plurality of smaller balls are contained, the smaller balls acting as load-supporting bearing elements for the sphere. Such a spherical ground-engagement element functions as a wheel with the advantage that it can roll freely in any desired direction and the term "wheels" as used in the appended claims is to be interpreted accordingly.

The particular type of wheel fitted to the aid may depend on the purpose for which the aid will primarily be used. Thus, if the aid is to be used by a farmer, at least the front wheels will be provided with tyres which have tracks and other formations to obtain enhanced grip. On the other hand, if the aid is to be used by a golfer, the wheels will be provided with substantially smooth surfaces which will not cause damage to the greens.

The power of the motors (whether hydraulic or electric) may depend on the requirements of the user of the aid. Thus a heavily built farmer wishing to use the aid outdoors will require more power than an elderly lady using the aid to go shopping or around the house.

Although the platform is substantially unenclosed, apart from the framework 14, a detachable fitting (not shown) may be provided on the platform 10 for supporting a golf bag or the like. A further optional extra is a seat, possibly of a nature similar to a shooting stick, which is removably mounted in a socket (not shown) in the platform 10. The seat, if provided, may be such that the user of the aid is supported in an almost standing position such as would be appropriate for a farmer wishing to engage in clay pigeon shooting.

Claims

Claims:

1. A mobility aid comprising a platform on which the user of the aid can stand, a power source mounted on the platform, a plurality of ground-engaging wheels supporting the platform, said wheels including a pair of independently driven front wheels and one or more rear wheels, an upwardly extending structure at the front of the platform which is otherwise substantially unenclosed so as to permit the user to obtain access to the platform from the rear thereof or from either side, and control means mounted at or adjacent the top of the upwardly extending structure whereby the user can control the direction and rate of movement of the platform.

2. A mobility aid as claimed in Claim 1, in which the platform is substantially rectangular.

3. A mobility aid as claimed in Claim 2, which has two rear castor wheels.

4. A mobility aid as claimed in Claim 3, in which the four wheels supporting the platform are disposed at the four corners of the rectangle.

5. A mobility aid as claimed in Claim 3 or Claim 4, in which the driven front wheels are of larger diameter than the rear castor wheels.

6. A mobility aid as claimed in Claim 5, in which the driven front wheels are arranged for rotation about axes which are above the level of the platform support surface.

7. A mobility aid as claimed in Claim 1, in which the power source is an internal combustion engine.

8. A mobility aid as claimed in Claim 7, in which the engine drives a pump which supplies hydraulic fluid under pressure to reversible hydraulic motors which drive the front wheels.

9. A mobility aid as claimed in Claim 8, in which the control means are in the form of pivoted levers mounted at the top of the upwardly extending structure at the front of the platform.

10. A mobility aid as claimed in Claim 9, in which the levers are pivotable towards one another to effect forward driving movement of the hydraulic motors are away from one another to effect rearward driving movement of the hydraulic motors.

11. A mobility aid as claimed in Claim 1, in which the power source comprises one or more rechargeable electric batteries.

12. A mobility aid as claimed in Claim 11, in which the front wheels are driven by reversible electric motors.

13. A mobility aid as claimed in Claim 12, in which the control means are in the form of a pair of switched mounted at the top of the upwardly extending structure at the front of the platform.

14. A mobility aid as claimed in Claim 5 or Claim 6, in which the power source is positioned on the platform so that its centre of gravity is substantially on the front-to-back centre-line of the platform and is spaced a significant distance to the rear of the axes of the front wheels.

15. A mobility aid as claimed in Claim 5 or Claim 6, in which a front frame member extends from side-to-side of the mobility aid forwardly of the supporting surface of the platform, and in which the drive wheels are mounted on the front frame member by means of stub axles.

16. A mobility aid as claimed in any one of the preceding claims in which, as viewed in side elevation, the upwardly extending structure at the front of the platform is inclined rearwardly.

17. A mobility aid as claimed in Claim 1, which has a four-wheel-drive system.

18. A mobility aid as claimed in Claim 17, which includes belt or chain drives whereby the rear wheels of the aid are driven from the front wheels.

19. A modification of the mobility aid as claimed in Claim 1, in which the ground-engaging wheels are replaced by a pair of independently driven tracks.

20. A mobility aid as claimed in Claim 1, in which the or each rear wheel comprises a spherical element slightly less than half of which projects from a support housing.

21. A mobility aid constructed and arranged to operate substantially as hereinbefore described with reference to and as shown in the accompanying drawings.