WO2015040538A1

WO2015040538A1 - Wheelchair propulsion arrangement

Info

Publication number: WO2015040538A1
Application number: PCT/IB2014/064544
Authority: WO
Inventors: Marthinus Gerhardus Jacobus Fourie
Original assignee: PELTERET, John Spencer; DE LANGEN, Rene
Priority date: 2013-09-19
Filing date: 2014-09-16
Publication date: 2015-03-26

Abstract

The invention discloses a wheelchair propulsion arrangement for a wheel of a wheelchair, which includes a frame being adapted to be circumferentially slidably mounted to the wheel; and a lever pivotally joined to the frame, wherein the lever has a foot being adapted to selectively frictionally engage a tyre of the wheel, and wherein the lever has a handgrip located above an armrest of the wheelchair. The frame partially circumferentially encloses the wheel, namely enclosing a rim and a tyre of the wheel.

Description

WHEELCHAIR PROPULSION ARRANGEMENT

FIELD OF INVENTION

The present invention relates to a wheelchair propulsion arrangement.

More particularly, the present invention relates to a wheelchair propulsion arrangement for the manual propulsion of a wheelchair.

BACKGROUND TO INVENTION

Most wheelchairs are propelled by hand by means of the person sitting in the wheel chair reaching down and gripping a circumferential handrail located radially inwardly of the wheelchair's wheel. However, this can be cumbersome for elderly people or those with injuries who may struggle to reach down to the handrail. It is therefore desirable to provide a drive means that is more easily reachable.

Such a drive means in known from US 5303945 wherein there is provided an attachment for a wheel chair having an arm joined to the wheel axle of the wheel chair and extending across the seat of the wheelchair. As this arm extends across the seat, people may encounter difficulties in getting in or out of the chair. Also, the arm may cause a blockage when attempting to enter confined spaces.

It is an object of the invention to suggest a wheelchair propulsion arrangement which assists in overcoming these problems. SUMMARY OF INVENTION

According to the invention, a wheelchair propulsion arrangement for a wheel of a wheelchair includes a frame being adapted to be circumferentially slidably mounted to the wheel; a lever pivotally joined to the frame, wherein the lever has a foot being adapted to selectively frictionally engage a tyre of the wheel, and wherein the lever has a handgrip located above an armrest of the wheelchair.

The frame may partially circumferentially enclose the wheel, namely enclosing a rim and a tyre of the wheel.

The frame may be attached to the wheel by various means, such as by bolting it together or clipping it to the rim.

The frame may be provided with internal rollers, whereby the rollers engage an outer surface of the tyre and are adapted to reduce friction between the frame and the tyre.

The lever may extend through a slot provided in the armrest.

The foot may be shaped as a flat plate or disc or it may be curved to conform to the surface of the tyre.

The propulsion arrangement may include a biasing means and/or spring to assist in moving the frame circumferentially around the wheel.

The biasing means and/or spring may be a coil spring, such as a tension or expansion coil spring. The invention extends to a wheelchair provided with a wheelchair propulsion arrangement as described herein.

Further according to the invention, a wheelchair propulsion arrangement for a wheel of a wheelchair includes a lever being adapted to be circumferentially moveably mounted relative to the wheel, wherein the lever has a foot being adapted to selectively frictionally engage a tyre of the wheel, and wherein the lever has a handgrip located above an armrest of the wheelchair; and locating means for positioning the foot in proximity to the tyre.

BRIEF DESCRIPTION OF DRAWINGS

The invention will now be described by way of example with reference to the accompanying schematic drawings.

In the drawings there is shown in:

Figure 1 : A perspective view of a wheelchair provided with a wheelchair propulsion arrangement according to the invention;

Figure 2: A left side view seen along arrow II in Figure 1 ;

Figure 3: An enlarged scale left side view of the area indicated by arrow III in

Figure 2;

Figure 4: A left side view of the wheelchair of Figure 2 showing the wheelchair propulsion arrangement in a retracted position; and Figure 5: A left side view of the wheelchair of Figure 2 showing the wheelchair propulsion arrangement in an extended position.

DETAILED DESCRIPTION OF DRAWINGS

Referring to the drawings, there is shown a wheelchair being generally indicated by reference numeral 10. The wheelchair 10 is of a conventional type having a frame 12 supporting a seat 14 with backrest 16, and having opposite armrests 18, 20. Opposite large drive wheels 22, 24 are rotatably joined to the frame 12 on the outer sides thereof. Each drive wheel 22, 24 has a rim 26 onto which is fitted a tyre 28.

As the left and right sides of the wheelchair 10 are mirror images of each other, the following description will be limited to describing the right side only - it being understood that the same description will be equally applicable to the right side thereof.

Mounted on the drive wheel 22 is a wheelchair propulsion arrangement in accordance with the invention, being generally indicated by reference numeral 50. The propulsion arrangement 50 includes a hollow frame 52 that partially circumferentially encloses the rim 26 and the tyre 28 with the frame 52 being slidable thereon so that the frame 52 can slide backwards and forwards around the drive wheel 22. The frame 52 can be attached to the wheel 22 by various means, such as by bolting it together or clipping it to the rim 26.

Opposite rollers 54,56 are provided internally of the frame 52 and joined thereto, with the rollers 54,56 engaging the outer surface of the tyre 28. The rollers 54,56 reduce friction between the frame 52 and the tyre 28 as the frame 52 slides around the wheel 22.

The frame 52 pivotally supports a lever 58 at pivot 60. The lever 58 has an arm 62 extending upwardly from the pivot 60 and terminating in a handgrip 64. Preferably the arm 62 extends through an elongated slot 66 provided in the armrest 18 so that the handgrip 64 is located above the armrest 18 for easy gripping by a person sitting in the wheelchair 10. The slot 66 has a back edge 66.1 nearest to the backrest 24 and a front edge 66.2 furthest from the backrest 24.

The lever 52 further has a leg 68 extending from the arm 62 towards the wheel 22. The leg 68 terminates in a foot 70 for contacting the tyre 28. The foot 70 can be shaped as a flat plate or disc or it can be curved to conform to the surface of the tyre 28. The foot 70 is adapted to frictionally grip against the tyre 28.

A biasing means in the form of a spring 72 is provided to assist in moving the propulsion arrangement 50 towards the backrest 24. The spring 72 can be a coil spring, such as the tension coil spring as illustrated, being provided between the frame 52 and the backrest 24. Alternatively, the spring 72 can be an expansion spring located forward of the frame 52.

In use, when the propulsion arrangement 50 is in its position of rest as shown in Figure 4, the frame 52 will be retracted towards the backrest 24 to such an extent until either the coil spring 72 is fully compressed or until the arm 62 abuts against the back edge 66.1 of the slot 66. A person is then able to drive the wheel 22 forwards by moving the lever 58 forward along the slot 66. The forward force applied to the lever 58 causes it to pivot around pivot 60 so that the foot 70 presses against and frictionally engages with the tyre 28, thereby resulting in the propulsion arrangement 50 being joined stationary to the wheel 22 and causing rotation thereof as the lever 58 is moved along the slot 66.

Once the lever 58 reaches the front edge 66.2 (shown in Figure 5), the person relaxes their grip so that the foot 70 is no longer pressed onto and frictionally engages with the tyre 28. The person can then retract the lever 58 back to its rest position whereby the propulsion arrangement 50 will slide circumferentially along the wheel 22 while the wheel 22 itself remains stationary. The spring 72 assists in moving the propulsion arrangement 50 back to the rest position.

The repetitive movement of the propulsion arrangement 50 as described above enables a person to move the wheelchair 10 forwards, assuming the same movement is caused on both opposite drive wheels 22 simultaneously. The wheelchair 10 can be turned by moving the propulsion arrangement on only one of the drive wheels 22.

In an alternative embodiment, not shown in the drawings, the frame 52 may be omitted. In such case the lever 58 includes a roller engaging against the underside of the armrest 18 adjacent to the slot to assist in positioning the foot 70 in the correct location in relation to the tyre 28. The underside of the armrest 18 may be curved having a curvature being concentric to the diameter of the tyre 28.

Claims

PATENT CLAIMS

1 . A wheelchair propulsion arrangement for a wheel of a wheelchair, which includes

(a) a frame being adapted to be circumferentially slidably mounted to the wheel; and

(b) a lever pivotally joined to the frame, wherein the lever has a foot being adapted to selectively frictionally engage a tyre of the wheel, and wherein the lever has a handgrip located above an armrest of the wheelchair.

2. An arrangement as claimed in claim 1 , in which the frame partially circumferentially encloses the wheel, namely enclosing a rim and a tyre of the wheel.

3. An arrangement as claimed in claim 2, in which the frame is attached to the wheel by various means, such as by bolting it together or clipping it to the rim.

4. An arrangement as claimed in any one of the preceding claims, in which the frame is provided with internal rollers, whereby the rollers engage an outer surface of the tyre and are adapted to reduce friction between the frame and the tyre.

5. An arrangement as claimed in any one of the preceding claims, in which the lever extends through a slot provided in the armrest.

6. An arrangement as claimed in any one of the preceding claims, in which the foot is shaped as a flat plate or disc or it is curved to conform to the surface of the tyre.

7. An arrangement as claimed in any one of the preceding claims, which includes a biasing means and/or spring to assist in moving the frame circumferentially around the wheel.

8. An arrangement as claimed in claim 7, in which the biasing means and/or spring is a coil spring, such as a tension or expansion coil spring.

9. A wheelchair propulsion arrangement for a wheel of a wheelchair, which includes a lever being adapted to be circumferentially moveably mounted relative to the wheel, wherein the lever has a foot being adapted to selectively frictionally engage a tyre of the wheel, and wherein the lever has a handgrip located above an armrest of the wheelchair; and locating means for positioning the foot in proximity to the tyre.

10. A wheelchair propulsion arrangement for a wheel of a wheelchair substantially as hereinbefore described with reference to the accompanying drawings.

1 1 . A wheelchair, which includes a wheelchair propulsion arrangement as claimed in any one of claims 1 to 9.

12. A wheelchair substantially as hereinbefore described with reference to the accompanying drawings.