WO1995011656A1

WO1995011656A1 - A lifting seat chair for static and wheeled use by the infirm

Info

Publication number: WO1995011656A1
Application number: PCT/GB1993/002217
Authority: WO
Inventors: Karl Wingett Smith; Michael John Billington
Original assignee: Karl Wingett Smith; Michael John Billington
Priority date: 1993-10-28
Filing date: 1993-10-28
Publication date: 1995-05-04
Also published as: AU5343094A

Abstract

An articulated support platform comprises an assembly of components, some or all of the following variously hinged or otherwise joined together: Seat (1) Leg and Footrest (4) Back (6) and Armrests (8). The platform assembly is capable of adapting approximately to the postures adopted by the human body when sitting and standing and to transitional attitudes between these two extremes. It affords means of support for the infirm in all configurations. The articulated platform assembly is suitable for incorporation into an external frame, with or without wheels, rigid or collapsible, to serve as lifting seat chair, wheelchair or commode for the infirm. Guides and/or pivots to regulate the relative configuration of the component parts of the articulated platform are incorporated within the framework of the chair(s).

Description

Description A lifting seat chair for static and wheeled use by the infirm.

Technical Field

This invention relates to means of assisting an infirm person to rise from a sitting position to an upright stance and vice versa, with or without assistance from an able-bodied helper. Background Art

Lifting seat chairs for the infirm are well known; in many of these the seat or assembly of seat, back and armrests pivot around the front transverse edge of the seat to assist the user to rise. Few, if any, are adapted for use in wheeled chassis. Related art is known only to exist in the Applicants' Patent Application No. GB 9217407.7 which is complementary to this Application.

Disclosure of Invention

This present invention comprises an assembly of body support components - Footrest, Leg Support, Seat, Back and Armrests so connected together that they conform approximately to the posture of a user throughout the range of attitudes required to change from a sitting position to an upright stance and vice versa. In its simplest format a user in a sitting position leans forward thus moving his/her centre of gravity forward of a transverse horizontal pivot axis beneath the seat so that the forward weight shift causes the footrest to descend to floor level while the rear of the seat rises. The backrest - to which the armrests may be rigidly attached, is linked to the seat and the frame of the chair so as to rise with the seat and maintain an essentially constant attitude in relation to the floor datum. The backrest (and armrests if attached) also move forward throughout this process. The range of movement achieved may be varied by changes to the relative positions and proportions of the components of the articulated assembly; increased upward travel may also be derived from the use of external thrust means, which may be human, hydraulic, nechanical or electro-mechanical in origin. Transition from standing to a seated position is the reverse of the above sequence; the several components of the body support assembly afford confidence and comfort to a user throughout the range of movement. The response of the mechanism to small input forces is such that the incorporation of damping means is recommended. Figure 1 is a diagrammatic side view of a chair incorporating "swinging link" means of constraint to achieve the desired motions and Figure 2 illustrates the use of sliding guides to the same ends. One of a pair of chair sideframes 1 support a seat panel 2 on a transverse axis 3. The forward edge of the seat panel is hinged or otherwise connected to a combined leg and footrest assembly 4which may, if desired, also be connected to the sideframe by a swinging link 5. The relative lengths of the link 5 and of the forward overhang of the seat panel and their respective hinge positions determine the path to be followed by the assembly during its motion. Also, if desired, the footrest component may be hinged to the leg panel so as to fold away.

At the rear of the seat panel the back panel 6 is attached by hinge means; the swinging link 7 affords rigidity to the back panel at all times and constrains it to move in the desired manner during seat elevation and lowering. The forward ends of the links are attached to pivots on the sideframes.

Armrests 8 are alternatively attached to the back panel (in which configuration they rise with it) or to the sideframes. If desired they may be suitably hinged to fold.

Lower stop means to support the seat panel in the lower, seated cofiguration are necessary but obvious therefore they are not shown. Increased range of upward seat movement can be obtained by the incorporation of upward thrust means under the rear of the seat or onto the back panel; in this case incorporation of the transverse horizontal axis into a slider or channel system enables upward movement of the axis, seat rear, back and, when appropriate, armrests to continue after the footrest has descended to floor level.

In Figure 2 the essential objectives of the concept are achieved by alternative use of guide channels and sliders; the back panel and any attached components are constrained in attitude and path of motion by their incorporation of blocks running in channels 9 in the sideframes or vice versa while the footrest and leg support are similarly regulated by blocks and guide channels 10. The seat, when occupied, rests on support rails IX and both pivots about and slides on their forward ends.

Claims

1. An articulated support platform for the human body comprising some or all of the following:- Footrest, Leg panel, Seat, Backrest, Armrests, all hinged or otherwise joined together so as to follow the human body contours in its conventional sitting posture and throughout the range of attitudes adopted as it rises to the standing position and vice versa; its elevating motion can be considered in two stages: (i) in which the entire platform assembly rotates about a transverse horizontal axis incorporated into or situated beneath the seat and located at a distance from both front and rear edges of the seat and (ii) in which the centre of motion for the seat and backrest assembly is at or adjacent to the front edge of the seat or the footrest when this is lowered to floor level so that there is then no significant further motion of the leg panel or footrest when these are fitted.

2- An articulated support platform as claimed in Claim 1 mounted within a framework - static or wheeled, rigid or collapsible - which incorporates guide means (e.g. pivots, sliders or a combination of both) which constrain the articulated platform assembly to adopt a programmed sequence of configurations.

3- An assembly comprising seme or all cf the components claimed in Claim 1 or Claim 2 and equipped with powered means (e.g. mechanical, electro-mechanical, hydraulic, or human) to assist transition from sitting to standing and vice versa.

4- An articulated body support platform assembly as described in Claim 1, Claim 2 or Claim 3 whose motion is restricted to one or other of the two stages claimed in Claim 1 .

5- Anarticulated body support platform as claimed in Claim 1, Claim 2,* Claim 3 or Claim 4 and equipped with armrests attached so as to rise and fall with the backrest during the transition stages.

6- An articulated body support platform as claimed in Claim 1, Claim 2, Claim 3, Claim 4 or Claim 5 and provided with means to serve as commode.

^"7- An articulated body support platform as Claimed in Claim 1, Claim 2, Claim 3 or Claim 4 and provided with means for use in conjunction with a conventional toilet facility.

3 An articulated body support platform substantially as described herein with reference to Figures 1 and 2 of the accompanying drawing.