GB2391519A

GB2391519A - Folding chair with or without wheels

Info

Publication number: GB2391519A
Application number: GB0217836A
Authority: GB
Inventors: Rios Jose Luis Jasso
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-08-01
Filing date: 2002-08-01
Publication date: 2004-02-11
Anticipated expiration: 2022-08-01
Also published as: GB2391519B; GB0217836D0

Abstract

A foldable mechanism applied as an example in a wheelchair with divided firm sitting 1,2 and back firm support 3,4,5, that folds until the side frames 25, 24 stay side by side, the sitting surfaces stay opposed one of the other and the central element of the back 4 folds to the front and the back components 3, 5 flip downwards until they stay face to face with the sitting surfaces 1,2, with a mechanism consisting in a double parallelogram with diagonal locking elements stopping the rotation of the sitting surfaces around 180 degrees one from the other when the chair is open, the wheelchair includes accessories as the footrest and the armrest (Fig 5) that swings in terms of folding it, in the x, y plane or longitudinal vertical plane.

Description

1 2391519

FOLDING CHAIR WITH OR WITHOUT WHEELS

This invention is a foldable system applied to a chair that permits a comfortable support for the user when she or he sit on it and at the same time when the system is folded, a compact space saving unit, the system is applied and tested in a wheelchair, because in this context those features are essential for the user, but the system is not limited to a wheelchair or to a dining, or easy chair, camping chair or to a any kind of chair, and at the same time can be applied to any kind of chairs including a wheelchair.

A standard wheelchair whose mechanism consists in a x folding structure with user interface components or sitting surfaces consisting in hammock hanging canvases, offers poor body support and the way the wheelchair folds is not as compact as can be. The static chairs, meaning a normal chair, offer more elaborated ergonomics and a production engineering that a wheelchair lacks.

This chair solves a comfort problem at the same time when it is folded it can became a compact suitcase size unit.

A preferred embodiment of the invention will now be described with reference to the accompanying drawing in which: Figure 1 shows a perspective of the unfolded chair.

Figure 2 shows a front view of the unfolded chair.

Figure 3 shows a perspective of the mechanism Figure 4 shows a perspective of the folded chair Figure 5 shows a perspective of the chair accessories.

The features in this chair design are the user interface components, being these, the horizontal rigid support cushioned sitting surfaces 1 and 2, the vertical rigid support cushioned plane 3, 4, 5, designated as a back and lumbar support for the user, and a mechanism shown in Figure 3, keeping the comfort performance of these interfaces.

The horizontal rigid support cushioned sitting surface is divided in two equal proportions components, right 1 and left 2 and the division line runs along the length of the chair, from front to back, and in the centre of it looking the chair from the front as shown in Figure 2, in this horizontal line, the sitting planes are hinged and when the chair is folded, their surfaces stay around 360 degrees opposite one of the other as shown on Figure 4, in the rear extremity of the component that works as an axis of the sitting surfaces central hinge, there is another hinged component 6 where the vertical rigid support cushioned surface designated as a back support 3, 4, S. is attached, and folds in the vertical longitudinal plane and to the front of the chair, ending in a horizontal position and parallel to the axis of the sitting surfaces central hinge as shown in Figure 4.

The surface designated as a back and lumbar support is, looking in the transversal vertical plane or the front view of the chair, divided in three components 3, 4, 5 by vertical lines, making three surfaces, one central component 4 and two side components 3, 5, attached to the central component with a flexible component that acts as a hinge with a vertical axis parallel to the vertical plane, each side component is crossed by a tension diagonal element like a belt 7 that begins in the upper central component and ends in the wheelchair side frame, on both sides, this tension element relieves the loads of the surface designated as a back and lumbar support when a person is sitting in the chair, when the chair is being folded, the side components of the vertical back support rotate forward until describe almost a right angle with the central component, but as this central element is folding in the vertical longitudinal plane, and ends parallel to the axis of the sitting surface hinge, each surface of the side components of the back support ends face to face with the surface of the sitting plane as shown on Figure 4.

The mechanism components Figure 3 are the sitting planes named before whose opposed extremes are attached by hinges 22, 23 to the right 24 and left 25 frames of the chair, two horizontal components 8, 9 hinged together by an axis 10 that runs parallel to the sitting central hinged axis 11, this two elements 8,9, follow the movements of the sitting planes 1,2 describing a double symmetrical parallelogram in the transversal vertical plane or front view of the chair Figure 2, these components work as a tension- compression elements with the diagonal elements, as well as keep the box structure in the horizontal plane, and two diagonal hinged components 12, 13, whose axis 14 runs parallel to the sitting central axis 11 and whose extremes descend to each side of the chair having a common hinge axis 15, 16 with the extremes of the two horizontal components 8, 9, and attached as well to the chair frames 24, 25, the diagonal components limit the movement of the parallelogram, relieve the load from the user weight to the sides, and add structure to prevent twists in the longitudinal vertical plane and in the longitudinal horizontal plane. The mechanism components can be produced using injection-moulded plastic due to the special and complex shape of the hinges as well as to save weight.

A vertical solid element like a tube 17 joins the axis of the central hinge 10, with the axis of the sitting hinge 1 1. This tube passes through the axis of the diagonal elements hinge 14. So this axis slides up and down the vertical tube 17 when the chair is been folded.

This chair when it is designated to have wheels and to be used by a disabled person has other accessories shown on Figure 5 like the footrests 18 that folds rotating in the vertical longitudinal plane of the chair, a step 19 limits the footrest in position. The armrest 20 folds in the same plane of the footrest and its keep in place by a positioning mechanism 21.

Claims

1. A foldable chair that has firm sitting and back support both with pressure relive elements for the user comfort.

2. A chair as claimed that its sitting surface is divided in two equal parts and the back support is divided in three surfaces those folds over the divided sitting when the system is folded.

3. A chair that can have wheels or not which its mechanism is based in a double symmetrical parallelogram with a double diagonal locking components as shown on attached drawings.

4. A chair as claimed in any preceding claim that when it is designated to have wheels and to be used by a person not able to walk or with walking difficulties, can include elements for keeping the feet of the user in safe transit place, that folds in the longitudinal vertical plane or transversal horizontal axis in terms of achieving compactness.

5. A chair that when it is designated to have wheels as shown in the drawings, can be made in reinforced thermo fixed plastics, thermoplastics or in light metal alloys or in any combination of these materials or other materials as wood.

6. A chair substantially as herein described above and illustrated in the accompanying drawings.