EP1251762B1

EP1251762B1 - A chair having a seat of saddle-type

Info

Publication number: EP1251762B1
Application number: EP00915618A
Authority: EP
Inventors: Vagn Ekeroth; Magnus Lindfors
Original assignee: Ekeroth & Lindfors Design Hb
Current assignee: Ekeroth & Lindfors Design Hb
Priority date: 2000-01-25
Filing date: 2000-01-25
Publication date: 2006-03-22
Anticipated expiration: 2020-01-25
Also published as: DE60026831D1; DE60026831T2; EP1251762A1; WO2001054545A1; AU2000236849A1; NO20023517D0; NO20023517L

Description

The present invention relates to a chair that has a saddle-type seat which is supported by a centrally located leg post whose free end is pivotally supported against the underlying support surface, e.g. the floor.
Such "single-leg" chairs can be readily moved and provide a relatively large working radius, by virtue of the fact that the chair can be tilted or pivoted about the bottom end of the leg post, in other words at a relatively large vertical distance from the seat.

Description of the background art

A seating device of the kind that can be converted into a walking stick is known to the art from GB,A,2 210 784 (Home & Leisure Supplies). The seat and the leg of this known device can be separated one from the other, and the device includes beneath the seat a holder which enables the leg to be accommodated in two perpendicular directions, one for each of the aforesaid purposes. The seat must necessarily be both thin and light in weight, meaning that the design of the device is not user ergonomic when used for seating purposes. When the device is not in use, it must be supported in some suitable way, for instance in an umbrella stand or walking stick stand. In other words the device cannot be used conveniently in a place of work in which the user is forced occasionally to leave his/her chair, for instance in order to perform a task whilst in a standing position.
FR,A, 1 154 789 (Depouilly) teaches a chair that includes a seat and a forwardly sloping chair leg and two rearwardly extending support legs which are joined to the chair leg at a point above the midway region of the leg. The chair is intended to stand flat on an underlying support surface or floor surface and cannot be tilted forwards. The height of the seat - which is comparatively flat ― can be adjusted, but the seat does not have a convenient user ergonomic. The high position of the connection between the leg post and the support legs also causes the centre of gravity of the chair to lie relatively high-up, meaning that there is a significant danger of the chair toppling over when the user stands up.
US,A, 4 183 579 (Gonzales y. Rojas) teaches a chair that comprises a leg post and a saddle-shaped seat. The leg post, however, is not in contact with the underlying floor surface. Instead, the lower part of the chair is provided with three collapsible support feet and also has additional support legs which are joined to the leg post higher up, said chair thus having five contact points with the floor. The support feet are provided with suction cups for holding the chair in place, and the lower part of the leg post is joined to the overlying part of the post via a powerful spring which enables the chair to be tilted in any desired direction. The seat of this known chair arrangement does not, however, provide a user ergonomic sitting position and the chair has an unnecessarily complicated construction and is therefore expensive to produce and is difficult to move with the suction cups firmly affixed to the surface of the floor.

Object of the invention

The object of the present invention is to provide a chair of the aforedescribed kind which eliminates the aforesaid drawbacks and other drawbacks associated with known chairs, and which provides the user with great freedom of movement a conveniently ergonomic seating position, and which automatically moves to a rest position in which the user can take the weight off his/her feet.

Summary of the invention

These and other objects of the invention are fulfilled by an inventive chair of the aforedescribed kind that has the characteristic features set forth in the characterising clause of Claim 1.
Because the seat has a shape similar to that of a horse's saddle that includes an upper part and downwardly extending side parts that have a gentle or smooth concave curvature, there is provided for the user a highly beneficial seating position from an ergonomic aspect, with the possibility of lightening the load on the seat by the user using his/her own legs to this end when the chair is tipped forwards. The downwardly extending side parts of the chair enable movements carried out by the user in a sitting position to be well controlled.
Because of the low position of the connection of the support legs with the leg post, the centre of gravity of the chair is situated low down on the chair, meaning that the chair will automatically return to its slightly rearwardly sloping rest position when the user leaves the chair, for instance in order to perform a task in a standing position.
The height adjustable upper part of the leg post further contributes to the ergonomic design of the chair and the significant mobility of the user in a seated position while using his/her own legs to bring the chair into different attitudes, for instance a forwardly inclined attitude relative to the floor surface, with the user thus constantly sitting in a correct position with no weight acting on the user's legs. These characteristic features of the inventive chair are achieved by supporting the upper part of the leg post resiliently and telescopically by means of a gas spring mounted in the lower part of said leg post.
It is preferred in practice for the axis of the leg post in the rest position of the chair to lie in a vertical symmetry plane through the centre part of the seat. This facilitates the automatic return of the chair to its rest state and ensures greater stability in this state of the chair.
The leg post will conveniently be fitted with a ferrule or corresponding device made of rubber or some similar friction enhancing material that will function to grip against the floor surface. This will prevent the risk of the chair sliding over the floor surface when the chair is tilted in use at different angles relative to the floor.
The rear side of the seat conveniently includes a device for adjusting the height of the seat. The seat will suitably be fitted with two such height adjusters, namely one each side of the seat, so that the user may adjust the height of the seat with either his left or his right hand.
The rear side of the seat also conveniently includes a handle with which the chair can be carried, said handle being positioned between the two height adjusters in the case of the aforedescribed embodiment.
Release of either of the adjusters at the same time as the wearer stretches his legs will cause the seat to automatically move to a new sprung position at a higher level.
Actuation of either adjuster in another direction whilst exerting pressure on the seat will, instead, cause the seat to take a lower sprung position.
The invention will now be described with reference to an exemplifying embodiment thereof and also with reference to the accompanying drawings.

Brief description of the drawings

Figure 1 is a perspective side view of an inventive chair and shows the chair in an approximately vertical use position.
Figure 2 is a perspective side view of the chair according to Figure 1 and shows the chair in a slightly rearwardly inclined rest position.
Figure 3 is a perspective rear view of the saddle-like chair seat and shows associated devices for adjusting the height of the chair.
Figure 4 illustrates the seat from beneath and shows said associated chair-carrying and height adjusters, said seat being shown removed from the leg post of the chair.

Description of preferred embodiments

Figures 1 and 2 illustrate an inventive chair 1 that includes a saddle-type seat 2. Figure 1 shows the chair in an approximate vertical use position, whereas Figure 2 shows the chair in a somewhat rearwardly inclined rest position, in which two affiliated support feet 4a are in contact with the underlying floor surface.
The support feet 4a are mounted on the free end of two support legs 4 which are joined to the central leg post 3 of the chair in the region of its lower portion.
The seat 2 has a horse saddle shape that includes an upper part 2a having an outwardly concave curvature, and downwardly extending side portions 2b having an outwardly concave curvature.
The leg post 3 is comprised of two main parts, these being a lower part 3a which carries the support feet 4a, and the telescopic upper part 3b carrying the seat 2.
Although not shown, the lower part 3a of the leg post accommodates a gas spring which springily supports the upper part 3b of the leg post carrying the seat 2. Provided beneath the actual seat 2 on the rear side thereof are right and left air-spring actuators 5 which can be manipulated by the user's right or left hand. The air spring is constructed so that no relative rotation will take place between the parts 3b and 3a of the leg post, but only around the points of contact of the chair with the floor surface. Consequently, the leg supports 4 will always be orientated rearwardly in relation to the seating direction.
A chair carrying device 6 is provided between the two actuators 5.
A rubber ferrule 3c is fitted to the bottom part 3 a of the leg post and is in contact with the floor surface so as to prevent the chair from sliding relative to said surface.
Figure 1 shows the chair in an approximately vertical use position, from which it can be swung in different directions corresponding to the various tasks to be carried out by the user at that time, this omnidirectional movement of the chair being allowed by the gripping action of the feet against the underlying floor surface.
The upwardly concave upper part 2a of the seat 2 and its downwardly extending, outwardly concave side parts 2b afford a comfortable and ergonomic, beneficial seating posture to the user. The user also has good control over the chair and is able to guide the chair in its different movements whilst in a seating position, with the aid of his/her legs and with his/her feet in contact with the floor.
When seated on the seat, it is natural for the user to sit with his/her legs relatively wide apart, so as to obtain a natural and stable seating posture.
As the user leaves the chair, for instance to carry out a task in a standing position, the chair will automatically return to the rest position shown in Figure 2, with the support feet 4a in contact with the floor. The chair will be held stable in said rest position and will not topple even should the user leave the chair when the leg post has a not-insignificant forward lean in relation to a vertical line, due to the low level at which the support legs 4 are connected to the leg post 3, therewith giving the chair a low centre of gravity.
In the rest position of the chair shown in Figure 2, the axis of the leg post lies in a vertical symmetry plane passing through the centre portion 2a of the seat 2.
One particular advantage afforded by the inventive chair is that it enables the user to move with a high degree of freedom in an active position, and also allows the user to take the weight of his/her feet in the rest position of the chair, this position being assumed automatically by the chair as the user leans backwards.

Claims

A chair comprising a central leg post (3) which is pivotally supported against an underlying support surface at one end of the post, and a saddle-type seat (2) supported by said leg post, wherein
a) the lower part of the leg post (3) has rearwardly projecting leg supports (4) whose free ends form support feet (4a) positioned on the rear side of the chair;

b) the leg supports (4) are orientated relative to the leg post (3) such as to be out of contact with the underlying support surface when said leg post is in a vertical position or a forwardly inclined position;

c) the leg post (3) includes a lower part (3 a), which carries the support feet (4b), an upper part (3b) which is mounted telescopically in said lower part (3a) and which carries the seat (2), and a gas spring which enables the height of the seat to be adjusted, characterised in that

d) the seat (2) has a shape similar to that of a horse's saddle and includes an upper part (2a) that has a concave outward curvature, and downwardly extending side-portions (2b) that have an outward concave curvature; and

e) in that the leg post (3) and the support feet (4b) function to hold the chair in a rest position in which the leg post is inclined slightly rearwardly.
A chair according to Claim 1, characterised by an actuator (5) for actuating adjustment of the seat height, said actuator being fitted on the rear side of the seat (2)
A chair according to Claim 2, characterised in that the chair has an actuator (5) on each side of the rear part of the seat (2).
A chair according to Claim 3, characterised in that the gas spring functions to move the seat (2) automatically to a higher position in response to activation of an actuator (5).
A chair according to any one of Claims 1-4, characterised by a chair carrying device located underneath the rear central part of the seat.