GB2388824A

GB2388824A - Wheelchair with foldable, angle settable backrest

Info

Publication number: GB2388824A
Application number: GB0310332A
Authority: GB
Inventors: James William Taylor
Original assignee: Remploy Ltd
Current assignee: Remploy Ltd
Priority date: 2002-05-08
Filing date: 2003-05-06
Publication date: 2003-11-26
Also published as: GB0310332D0; GB0210530D0

Abstract

A wheelchair has a seat frame (1), and a backrest (10) pivoted onto the seat frame (1) so that it can be folded towards the seat (6) for transport or storage. It also includes a combined latch and backrest angle setting fitment (20) which is engagable with and releasably latchable onto the seat frame (1) behind the backrest pivot (12, Fig 3/4). The extent of the fitment (20) is variable, for example by adding spaces (29), to vary the attitude of the backrest (10) in its non-folded, in use, configuration.

Description

WHEELCHAIR

Many wheelchairs have a backrest which folds to make the unoccupied wheelchair more compact for storage or 5 transport. The optimum angle of the backrest to the seat changes with the postural needs of the occupant. It is therefore desirable to have a backrest which not only folds, but which is also angle-settable. Once set for use, it is desirable that the backrest is capable of being 10 locked against folding towards its folded position.

Backrest angle setting can be achieved by means of a segment plate secured to the backrest with a series of holes at different angles, or a jacking screw feature which 15 increases or decreases the angular distance travelled by a folding backrest. Locking the backrest in position against folding is often achieved by the action of a spring- loaded latch plate which can be released by the user when the backrest is to be folded.

Many discerning and active wheelchair users do not appreciate the cluttered appearance of conventional backrest adjustment setting and locking components or their added weight.

According to this invention a wheelchair having a seat frame, and a backrest pivoted onto the seat frame so that it can be folded towards the seat for transport or storage, also includes a combined latch and backrest angle setting 30 fitment which is engagable with and releasably latchable onto the seat frame behind the backrest pivot, the extent of the fitment being variable to vary the attitude of the backrest in its non-folded, in use, configuration.

35 Preferably the figment includes a foot portion which engages on and at least partly surrounds the seat frame and includes a latch such as a spring loaded quarter turn cam

( operated locking pin. The extent of the fitment between the foot portion and the connection of a fitment with the backrest is variable, for example, by providing two telescoping portions for example, screw threaded into one 5 another or by providing an assembly of removable spacers.

Preferably the fitment includes means to vary the angle between the foot portion and the portion of the backrest to which the fitment is attached. This may be 10 formed by having a pair of matching arcuate surfaces that can rotate with respect to one another. It is preferred that these arcuate surfaces include inter-engaging splines, so that the surfaces, once set in position against one another, interlock and are retained in that set 15 position.

Preferably, the backrest includes a generally hoop shaped component the free ends of which are pivoted onto the seat frame in front of the squab of the backrest and 20 the middle of which extends behind the squab of the backrest, and two separate generally upright components which support the squab and the bases of which are connected to a fitment. When the backrest is arranged in this way its two components are rigidly fixed to one 25 another, for example, by welding.

A particular example of a wheelchair in accordance with this invention will now be described with reference to the accompanying drawings; in which: Figure 1 is a perspective view of the whole wheelchair from the left hand side and above; Figure 2 is an exploded perspective view of the backrest angle setting fitment; 35Figure 3 is a scrap side elevation of the assembled fitment; and,

Figures 4 and 5 are scrap side elevations of part of the right hand side of the wheelchair frame showing the frame portions adjusted at different angles.

5 This example of a wheelchair comprises two generally S-shaped side frames 1 and 2 the top parts of which form armrests 3, the middle parts of which form a seat frame and the lower parts of which support front castor wheels 4 and large propulsion wheels 5. The shape of the frames 1 and 10 2 provide for some inherent springing between a seat 6 and the wheels 4 and 5 as a result of the resilience of the side frames 1 and 2. This resilience can be complemented by one or two additional springs 7 mounted between curved cross-beams which connect the side frames 1 and 2. The 15 wheelchair also includes a footrest 9 which is connected to the side frames 1 and 2 and a backrest 10.

The backrest lO includes a tubular metal framework formed by a hoop shaped portion 11, the free ends of which 20 are pivotally connected to the frames 1 and 2 at pivot point 12 (see Figures 4 and 5) and upright tubular members 13. The members 13 may have pushing handles formed on their upper ends or the hoop-shaped portion may be used as a pushing handle 14. The members 13 support a squab 25 portion 15 of the backrest 10. The tubular portions 13 are welded onto the hoop portion 11. The lower end of the tubular portions 13 rest on and engage with the middle parts of the side frames 1 and 2 via fitments 20 shown most clearly in Figures 2 and 3.

The fitment 20 comprises a foot portion 21 which partially encircles the side frame 1 and 2 and which carries a captive sprung loaded locking pin 22 which can be withdrawn by a quarter turn rotation of a cam actuated 35 lever 23. The locking pin, in use, engages in an elongate hole 24 on the side frames 1 and 2. The top portion of the foot 21 includes an arcuate recess 25 formed with

transverse salines 26. The rest of the fitment comprises a first latch washer 27 having an arcuate surface formed with salines 28 and number of spacers 29. An insert portion 30 which is fixed into the lower end of the tubes 5 13 has an internal screw thread and the whole fitment including a selected number of spacers 29 is held together by a bolt 31.

By varying the number of spacers 29 included in the 10 fitment 20 the effective length of the tubular member 13 is varied and hence the angle of the backrest 10 to the seat 6 of the wheelchair. Figure 4 shows the arrangement with two spacers 29 included where the angle between the seat and the backrest is less than 90 whereas Figure 5 shows 15 the configuration with no spacers 29 included where there is an obtuse angle formed between the seat 6 and the backrest lO. In a setting up operation the number of spacers 29 to be included in the fitment is determined and then with the bolt 31 not completely tightened the backrest 20 is erected until the foot 21 engages the frames 1 and 2.

The angle of the foot 21 relative to the tubular portion 13 is then adjusted by moving the latch washer 28 with respect to the surface 25 of the foot 21 until the angle of the foot 21 corresponds to that of the frame 1 and 2. The 25 appropriate splines 26 and 28 on the surfaces 25 and 27 interlock and the bolt 31 is tightened to retain the foot 21 at the appropriate orientation with respect to the tube 13.

Claims

1. A wheelchair having a seat frame, and a backrest pivoted onto the seat frame so that it can be folded towards the seat for transport or storage, including a 5 combined latch and backrest angle setting fitment which is engagable with and releasably latchable onto the seat frame behind the backrest pivot, the extent of the fitment being variable to vary the attitude of the backrest in its non-

folded, in use, configuration.

10 2. A wheelchair according to claim 1, in which the fitment includes a foot portion which engages on and at least partly surrounds the seat frame and includes a latch.

3. A wheelchair according to claim 2, in which the latch is a spring loaded quarter turn cam operated locking pin.

15 4. A wheelchair according to any one of the preceding claims, in which the extent of the fitment between the foot portion and the connection of a fitment with the backrest is variable by providing an assembly of removable spacers.

5. A wheelchair according to any one of the preceding 20 claims, in which the fitment includes means to vary the angle between the foot portion and the portion of the backrest to which the fitment is attached.

6. A wheelchair according to claim 5, in which the means to vary the angle are formed by having a pair of matching 25 arcuate surfaces that can rotate with respect to one another. 7. A wheelchair according to claim 6, in which the arcuate surfaces include inter-engaging splines, so that the surfaces, once set in position against one another, 30 interlock and are retained in that set position.

8. A wheelchair according to any one of the preceding claims, in which the backrest includes a generally hoop shaped component the free ends of which are pivoted onto the seat frame in front of the squab of the backrest and 35 the middle of which extends behind the squab of the backrest, and two separate generally upright components

which support the squab and the bases of which are connected to a fitment.

9. A wheelchair according to claim 8, in which the two components of the backrest are rigidly fixed to one another by welding.

10. A wheelchair substantially as herein described with reference to the accompanying drawings.