AU2008100468A4 - Chair - Google Patents

Description

00 00 00 ^1- 0D 0q

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION Innovation Patent Applicant: Anthony Joseph Op de Coul Invention Title:

CHAIR

The following statement is a full description of this invention, including the best method for performing it known to me: P77505.AU P. Set FWhNg Appl"c.lOn 200.5-21.dc (U) 2 00

CHAIR

This invention relates to a chair and, in particular, a wheeled chair.

C( Many chairs have a leg structure which embraces wheels so 00 it is simple exercise to move the chair about without

\O

having to lift the chair.

0i0 However, in hospitals, homes for the elderly and other 00 establishments that care for the infirmed, whilst there is C1 a need for chairs which can be moved easily and without lifting, it is also important that these chairs are not free to move all the time thus rendering access by the infirmed or elderly a hazardous exercise.

It is these issues that have brought about the present invention.

According to the present invention there is provided a chair having a wheeled leg structure, at least one of the wheels having a brake adapted to assume a locked position when the chair is unoccupied and an unlocked position when the chair is occupied.

The brake preferably engages the wheel in the locked position to prevent rotation of the wheel. Preferably a spring urges a projection to engage the wheel when the chair is unoccupied and to be displaced away from the wheel when the chair is occupied. In a preferred embodiment, it is the load of the occupant which displaces the spring away from the wheel.

Preferably the wheeled leg structure comprises four legs, each of which terminates in a wheel. A brake is preferably associated with in each rear wheel of the chair.

N:\Meloume\CasesPatent\770 00-77999\P77595.AA eSpeofication 2008-5-21 doc 21105/08 00 O An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which: C- 5 Figure 1 is a perspective view of a wheeled chair; 00 Figure 1A is an enlarged view of the wheeled structure of

\O

Sa front leg of the chair; 00 10 Figure 3 is a side elevation view of the chair in a locked 0 configuration; Figure 4 is a side elevation view of the chair in an unlocked configuration; Figure 4A is a forward perspective view of a wheel structure for a rear leg of the chair; Figure 4B is a rear perspective view of the wheel structure; Figure 5A is a plan view of the wheel structure; Figure 5B is a side elevational view of the wheel structure; Figure 5C is a front elevational view of the wheel structure; Figure 5D is a rear elevational view of the wheel structure; Figure 5E is a cross-sectional view of the wheel structure taking along the lines AA of Figure 5C, showing the wheel in an unlocked configuration; N:\Melboume\CasesPatent\77000-779991P77595.ALSpecis\P77595 AU Specification 2008-5-21 doc 21/05/08 0O 4 00 O Figure 6B is a cross-sectional view of the wheel in a locked configuration; and Figures 7A and 7B are side elevational views of the wheel in an unlocked and locked configuration.

00 The accompanying drawings illustrate a wheeled chair

\O

The chair has a seat 11, a back 12, and four downwardly extending legs 13, 14, 15, 16, the front 13, 14 and rear 00 10 legs 15, 16 are interconnected by an S shaped brace 17 as 0shown in Figure A. The end of each front leg 13 or 14 I supports a housing 20 that has a pair of downwardly projecting flanges 21, 22 which support a wheel 22, which is rotatable about an axle 24 that locates across the flanges 21, 22. The wheel 22 is constrained to rotate in a single plane.

Each rear leg 15, 16 terminates in a wheel structure which is shown in detail in Figures 5 to 7.

Each wheel structure 30 comprises an L shaped bracket 31 with an upright 32 which is bolted or screwed to the rear of the leg 15, 16. The L-shaped bracket 31 supports two substantially triangular side plates 35, 36 that are joined at the front by a bracing plate 37. The side plates 35, 36 define a space 40 in which a wheel 41 can be located and an axle 42 is positioned to project across the base of the plates to support the wheel, allowing the wheel 41 to rotate in a single plane between the side plates 35, 36.

The wheel structure 30 also includes a brake in the form of a V-shaped piece 50 of rectangular spring steel. It has one arm 52 attached to the underside of the L-shaped bracket 31 and the other arm 53 arranged to project down towards the periphery of the wheel 41. A leaf spring of rectangular profile, is located between two spaced lugs N:\Melboum e\CasesPaateni\7700-77999\P77595.ALA pciSpecification 2008-5-21.doc 21/05/08 00 O 61, 62 to engage the underside of the V-shaped brake piece The lugs 61, 62 extend across the triangular plates 36. In the laden position shown in Figures 6A and 7A, the load on the chair forces the L-shaped bracket to assume a position where the upright 32 is vertical and the lower plate horizontal. This has the effect of 00 compressing the leaf spring 60 to the position shown in

\O

Figure 6A. As soon as the load is taken off the chair, the leaf spring 60 forces the L-shaped bracket 31 upwardly 0 10 to tilt the whole assembly, forcing the downward projecting arm 53 of the brake piece 50 to engage the CI periphery of the wheel 41 to prevent the wheel from rotating, thus locking the wheel.

As shown in Figures 2 and 3, which are side elevational views of the chair 10, the back 12 of the chair 10 is slightly raised in the unloaded position as the rear wheels 41 assume the locked configuration shown in Figure 2. When a person sits on the chair, or someone pushes down on the back 12 of the chair 10, the leaf spring 60 is compressed to release the brake and thereby allow the chair to be easily moved on the wheels 41, 23.

In the preferred embodiment, the wheel structures are such that the chair 10 can only move in a single plane. It is however understood that this invention also envisages the situation where the wheels can have movement in any direction by use of wheels such as castor wheels or wheels with limited movement in certain directions. It is further understood that the chair 10 may take many shapes and forms and does not necessarily have to be four legged.

Other leg structures are envisaged by this invention.

In a situation where a chair like this is used in a hospital or in the residence of the elderly or the infirmed, a person seeking to sit on the chair 10 knows as he or she grips the chair that the chair is locked in N:\Melboume\Cases\Patent\77000-77999\P77595.AUSpecis77595AU Specification 2008-5-21 doc 21/05108 00 0 position and will not slide away as that person sits down.

Once the person has sat down the brake is released which then allows that person to either manoeuvre the chair about with his or her legs, or for an aide to push the C< 5 chair. Similarly, in a situation where it is desired to move the chairs about a room, it is a simple exercise to 00 push down the chair from the rear, thereby releasing the

\O

brake and effecting wheeled movement.

00 10 In the claims which follow and in the preceding Sdescription of the invention, except where the context CI requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

N:elboume\Cases\Paent77000-77999\P77595.AU\Spcs\P77595 AU Specification 2008-5-21 doc 21/05/08

Claims (3)

1. 2. The chair according to claim i, wherein the brake engages the wheel in the locked position to prevent 0 i0 rotation of the wheels. 00 CI 3. The chair according to either claim 1 or claim 2, wherein a spring urges a projection to engage the wheel when the chair is unoccupied, the spring causing the projection to be displaced away from the wheel when the chair is occupied.
2. 4. The chair according to claim 3, wherein it is the load of the occupant which compresses the spring to displace the projection away from the wheels. The chair according to any one of the preceding claims, wherein the wheeled leg structure comprises four legs each of which terminates in a wheel.
3. 6. The chair according to claim 5, wherein a brake is included in each rear wheel of the chair. N:olboume\Cases\Pate\77000-77999\P77595ASpecis\P77595.AU Specification 2008-5-21 .doc 21/05/08