NZ328792A - Foldable chair with back rest of variable inclination - Google Patents

Description

/ New Zealand No. 328792 International No. PCTI TO BE ENTERED AFTER ACCEPTANCE AND PUBLICATION Priority dates: 17.09.1996; Complete Specification Filed: 17.09.1997 Classification:^) A47C4/28.52; A61G5/08 Publication date: 26 August 1998 Journal No.: 1431 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION Title of Invention: Collapsible chair Name, address and nationality of applicant(s) as in international application form: LENDAL PTY LIMITED, an Australian company of 25 Ledgar Road, Balcatta, Western Australia, Australia " 'J -2- v> i- -■ I The present invention relates to a chair. More particularly, the invention relates to a chair having a seat and a back rest moveable with respect to the seat between a collapsed condition for transportation and storage, and an operative condition in which it is selectively angularly adjustable with respect to the seat so 5 that the inclination of the back rest can be adjusted according to the requirements of a user.

The invention has been devised particularly, although not solely, as a wheel chair.

With wheel chairs, it is common to have a seat and a back rest which is 10 selectively adjustable with respect to the seat by angular movement about a horizontal pivot axis. This arrangement allows the back rest to be folded downwardly about the pivot axis into a storage position in which it rests against the seat. A difficulty with this arrangement is that in the folded condition, the back rest does not generally lie flat against the seat but rather assumes an 15 inclined position resting against the rear end section of the seat. This problem arises because of the low position of the pivot axis relative to the seat owing to a need to maintain the bottom edge of the back rest in close proximity to the seat when the back rest is in the operative condition. The inclined position of the back rest does not allow the wheel chair to be sufficiently compact for storage and 20 transportation in many vehicles commonly in use, such as station wagons. The wheel chairs are therefore constructed in sections which can be disassembled for transportation in such vehicles. However, the need to disassemble the wheel chairs introduces a procedure which is best avoided if possible.

It would be advantageous to provide a chair in which the back rest can be folded 25 onto the seat in order to assume a compact condition. The present invention seeks to provide such a chair.

The invention provides a chair comprising a seat and a back rest, link means pivotally connected to the seat about a first axis and pivotally connected to the *2 p, 792 PATENTS FORM NO. 5 Fee No. 1 &. 4: $340.00 PATENTS ACT 1953 COMPLETE SPECIFICATION COLLAPSIBLE CHAIR WE LENDAL PTY LIMITED, an Australian company of 25 Ledgar Road, Balcatta, Western Australia, Australia hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: | luflLLECfUAL PRu/EfiTY GFFICt j OF N.Z. ~3" 2 back rest about a second axis parallel to the first axis, the bade reST being angularly adjustable about the second axis for selectively varying the inclination of the back rest with respect to the seat, and the link means being angularly moveable with respect to the seat about the first axis for selectively elevating the 5 second axis with respect to the seat for folding of the back rest onto the seat.

Preferably , the angular movement of the link means elevates the second axis to an extent sufficient to allow the back rest to fold into a flat condition on the seat.

Conveniently, the link means is moveable about the first axis from a first condition in which it supports the back rest for angular movement thereof about the second 10 axis, and a second condition in which the back rest is folded onto the seat.

Conveniently, the link means includes a portion between the two pivot axis which is generally horizontal when the link means is in the first condition and generally vertical when th*5 link means is in the second condition.

The link means may comprise a pair of links positioned one at each side of the 15 back rest.

Preferably, a locking means is provided for selectively locking the link means in the first condition. This provides stability to the arrangement and ensures that the link means does not inadvertently pivot about the first axis when an occupant of the chair rests on the back rest or when the inclination of the back rest is adjusted.

The locking means may comprise a locking pin mounted on one of the links and moveable axially into and out of an engaging condition, the locking pin having a handle which can be gripped for moving the locking pin into and out of the engaging position and which can also be used for moving the link means from the 25 first condition to the second condition. Conveniently, there are two such locking pins, one associated with each of the links. : v 2 - 4 - * -J Preferably, each locking pin is biased into the engaging pos^^n.

A control means may be provided for selectively adjusting the inclination of the back rest with respect to a seat. The control device may comprise a telescopic ram.

The invention will be better understood by reference to the following description of one specific embodiment thereof as shown in the accompanying drawings in which: Fig. 1 is a schematic side view of a wheel chair according to the embodiment, the wheel chair having an occupant supporting portion with a 10 back rest in an upright condition; Fig 2 is a view similar to figure 1 with the exception that the occupant supporting portion is shown in a rearwardly tilted position; Fig. 3 is a schematic side view of the wheel chair shown in a collapsed condition, with the back rest folded onto the seat; Fig. 4 is a schematic perspective view of the occupant supporting portion of the wheel chair in the operative condition; Fig. 5 is a rear view of the occupant supporting portion in the operative condition; Fig. 6 is a schematic perspective view of the occupant supporting portion 20 in the collapsed condition; Fig. 7 is a rear view of the occupant supporting portion in the collapsed condition; Fig. 8 is a side view of the occupant supporting portion in the collapsed condition; Fig. 9 is a schematic view of a frame structure forming part of the occupant supporting portion, the frame structure being shown in an exploded form; and Fig. 10 is a schematic view illustrating procedures required to move the occupant supporting portion from the operative position into the collapsed condition.

The embodiment shown in the drawings is directed to a wheel chair which comprises an occupant supporting portion 11 supported on a mobile base structure 13. The occupant supporting portion 11 is selectively tiltable with respect to the mobile base structure 13 so that the occupant of the wheel chair can be supported in various positions, generally between an upright position and a rearmost inclined position. Two of such positions are shown in Figs. 1 and 2 of the drawings.

The occupant supporting portion 11 comprises a seat 15, a back rest 17, and arm rests (which are not shown in the drawings).

The seat 15 includes a cushioned seat portion 21 mounted on a seat frame structure 23.

The back rest 17 comprises a back rest frame structure 25 and a cushioned back rest portion 36.

The seat frame structure 23 includes two longitudinal frame sections 27 at the sides thereof between which the cushioned seat portion 21 is supported. The longitudinal frame sections 27 extend rearwardly beyond the seat portion 21 and are connected one to another by a bridging frame section 33. The longitudinal frame sections 27 and the bridging frame section 33 are of integral construction.

The back rest frame structure 25 includes two longitudinal frame sections 35 at the sides thereof, and two transverse frame sections 37, 39. The transverse section 39 extends between, and is formed integrally with, the longitudinal sections 35 at the upper end thereof to provide a handle 41. The handle can be used to adjust the angular position of the back rest. The cushioned back rest portion 36 is supported between the longitudinal frame sections 35.

The back rest 17 is pivotally connected to the seat 15 by link means 43 comprising a pair of rigid links 45 positioned one to each side of the back rest 17 and a transverse element 46 extending between and fixed to the links.

Each link 45 comprises a first section 47 and a second section 49 disposed angularly with respect to the first section.

The first section 47 of each link 45 is pivotally connected at 48 to the respective longitudinal frame section 27 rearwardly of the seat portion 21 for pivotal movement about a substantially horizontal first axis. The frame section 27 has a mounting bracket 51 provided by a pair of spaced apart lugs 53 between which the link 45 is pivotally connected by a hinge pin to provide the pivot connection at 48.

The second section 49 of each link 45 is bifurcated and pivotally connected at 57 to the respective longitudinal frame section 35 for pivot movement about a second pivot axis parallel to the first pivot axis at 48. The back rest 17 can be pivoted about the second axis, for selectively varying its inclination with respect to the seat, according to the requirements of a user.

A control means 61 such as a manually operable telescopic ram is pivotally connected between the back rest from structure 25 and the seat frame structure 23. The telescopic ram 61 is selectively detachable from one or both of the back rest frame structure 25 and the seat frame structure 23 to allow folding of the back rest, as will be explained later. _ 7 _ " O - *- Each link 45 is angularly movable with respect to the seat 15 about its first axis at 48 for selectively elevating the second axis at 57 with respect to the seat for folding of the back rest 17 into a flat condition onto the seat, as best seen in Figs. 6 and 8 This angular movement of each link 45 is between a first condition (as shown in Fig 4) in which the link supports the back rest 17 for angular movement about the second axis, and a second condition (as shown in Fig. 6) in which the second axis is elevated and the back rest in a flat condition on the seat.

In the first condition, the first section 47 of each link 45 is generally horizontal 10 and rests on the respective longitudinal frame section 27 for stability. In this condition, the second section 49 extends upwardly in an angular fashion.

In the second condition, the first section 47 of each link 45 extends generally vertically.

A locking means 65 is provided for selectively locking each link 45 in the first 15 condition. This is to provide stability to the arrangement and ensure that each link 45 does not inadvertently pivot about its first axis at 48 when the occupant of the chair rests on the back rest 17 or when the inclination of the back rest is adjusted.

The locking means 65 comprises a locking pin 67 mounted on the second section 20 49 of each link 45 for axial movement into and out of engagement with a catch 69 fixed onto the respective longitudinal frame section 31. The catch 69 is received within the bifurcated second section 49 when the link 45 is in the first condition. The catch has a locking hole 70 into which the locking pin 53 is adapted to be received when the link 45 is in the first condition. The locking pin 67 has a handle 25 71 which can be gripped for releasing the locking pin from the catch 69 and also for moving the link 45 from the first condition to the second condition. For convenience, the locking pin 67 is biased into its engaging position. - 8 - '•*»' ia«Ji o i v *- In operation, the back rest 17 of the wheelchair can conveniently be moved from the operative position (as seen in Fig. 4) to a compact collapsed condition (as seen in Fig. 6) tor transportation and storage.

The procedures for moving the back rest 17 from the operative condition to the 5 collapsed condition are illustrated schematically in Fig. 10 of the drawings. The telescopic ram 61 is detached from the back rest 17 to allow the latter to pivot freely The locking means 65 are then released to allow the two links 45 to each pivot about the first axis at 48 from the first condition into the second condition. This elevates the second pivot axis and allows the back rest to lay flat on the seat 10 to provide a compact arrangement.

To return the back rest 17 to the operative condition, it is merely necessary to raise it from the seat 15, so causing it to pivot about the second axis. This procedure causes the links 45 to return to their first condition where they can be locked in place by the locking means 65. The back rest can then be set to the 15 desired inclination by attaching the ram 61.

From the foregoing, it is evident that the present invention provides a simple yet highly effective arrangement for folding a chair between operative and compact conditions.

It should be appreciated that the scope of the invention is not limited to the scope 20 of the embodiment described. "w Ura '.*/ f V>'

Claims (11)

WHAT WE CLAIM IS:

1 A chair comprising a seat and a back rest, link means pivotally connected to the seat about a first axis and pivotally connected to the back rest about a second axis parallel to the first axis, the back rest being angularly adjustable about the second axis for selectively varying the inclination of the back rest with respect to the seat, and the link means being angularly moveable with respect to the seat about the first axis for selectively elevating the second axis with respect to the seat for folding of the back rest onto the seat.

2. A chair according to claim 1 wherein the angular movement of the link means elevates the second axis to an extent sufficient to allow the back rest to fold into a flat condition on the seat.

3. A chair according to claim 1 or 2 wherein the link means is moveable about the first axis from a first condition in which it supports the back rest for angular movement thereof about the second axis, and a second condition in which the back rest is folded onto the seat.

4. A chair according to any one of the preceding claims wherein the link means includes a portion between the two pivot axis which is generally horizontal when the link means is in the first condition and generally vertical when the link means is in the second condition.

5. A chair according to any one of the preceding claims wherein the link means comprises a pair of links positioned one at e.ach side of the back rest.

6. A chair according to any one of preceding claims 3 to 5 wherein a locking means is provided for selectively locking the link means in the first condition.

7. A chair according to claim 6 wherein the locking means comprises a locking pin mounted on one of the links and moveable axially into and out of an engaging condition, the locking pin having a handle which can be gripped for moving the locking pin into and out of the engaging position and which can also be used for moving the link means from the first condition to the second condition.

8. A chair according to claim 7 wherein there are two locking pins, one associated with each of the links.

9. A chair according to claim 7 or 8 wherein each locking pin is biased into the engaging position.

10. A chair according to any one of the preceding claims further comprising a control means for selectively adjusting the inclination of the back rest with respect to a seat.

11. A chair substantially as herein described with reference to the accompanying drawings. LENDAL PTY LIMITED By its Attorneys TAMES ft WFJJ.q END OF CLAIMS INfi-LLECrU/d _,;;iY GFFlCul OF U.Z. 17 J J:-: ict.3 RECEIVED