WO1992021270A1

WO1992021270A1 - Chair

Info

Publication number: WO1992021270A1
Application number: PCT/DE1991/000479
Authority: WO
Inventors: Stefan Hoffmann
Original assignee: Sifa Sitzfabrik Gmbh
Priority date: 1990-04-05
Filing date: 1991-05-05
Publication date: 1992-12-10
Also published as: ATA81690A; AT394134B

Abstract

Described is a chair with a foot (1), a leg (2), a seat (3) whose inclination can be adjusted and which is mounted on the leg (2), and an adjustable back (4) which is mounted by means of a support arm (7) at least on the leg (2) so that it can be adjusted in a substantially horizontal axis (a3, a1, a4) from a first, substantially vertical, position in which it is substantially above the plane of the seat to a second, substantially lying, position in which it is substantially below the plane of the seat. The support arm (7) is made up of two parts (7a, 7b) which can be rotated with respect to each other about a substantially horizontal axis (a1) and locked in place with respect to each other.

Description

armchair

description

The invention relates to an armchair with a foot, a foot column, a seat arranged on the foot column, the inclination of which is adjustable, and with an adjustable backrest which is supported at least on the foot column by means of a support arm and which extends around at least one, essentially horizontal axis a first, substantially upright and located substantially above the seat level

Position of use in a second, essentially lying, and essentially below the seat level position of use is adjustable.

Convertible armchairs of this type are known from GB-PS 2 202 138 and WO-88/04903, in which a one-piece, extended support arm or support is provided for a backrest, which is used to convert one position of use into the other can be pivoted with the backrest body or leading over the seat of the chair. A disadvantage of these embodiments is that the pivot angle is limited by abutting the support arm, such as in the variant according to Fig. 2 of GB-PS 2 202 138, to the bottom part and that only the self-suspension of the extended arm instead of one for the backrest body own defined spring force is provided. Furthermore, in these known armchairs the process of tilting the seat is rigidly coupled with the process of pivoting the backrest. For example, according to GB-PS 2 202 138 a gear or a latching mechanism is provided and according to

Proposed by WO-88/04903, the seat is simultaneously tilted forward by the lower rail part of the support that comes up during the conversion. This has the disadvantage of less flexibility with regard to body-appropriate adjustments and represents an undesired restriction. In addition, a variant known from WO-88/04903 leads in which the conversion takes place by separating the backrest part and attaching it as a knee-rest to a foot part , through the separation steps to a corresponding operating effort.

A chair-like, convertible seat device is also known from DE-OS 36 23 224. This proposed solution is also based on a one-piece support arm, which, however, in contrast to the variants according to the above-mentioned GB-PS 2 202 138 must be U-shaped so that it can be pivoted past the front edge of the seat, leading over the seat surface. An additional effort compared to conventional office armchairs is also given by the required special storage part for such a U-shaped support arm.

From EP-A2-263 898 a knee chair has become known in which various adjustment options are provided in ergonomic terms. Among other things, the seat contact surface can be moved both in its plane and in height. GB-A-2 085 719 describes a basically conventional office armchair in which the backrest is formed in two parts and is adjustable by a special lever mechanism.

EP-Al-107 627 describes an armchair whose backrest is partly constructed in segments and partly contains a large number of internal adjusting devices in order to enable adaptation to the anatomical conditions of the user. The large number of stiffening segments that are connected to each other via levers or springs is remarkable. The associated adjustment mechanisms are also extremely complex.

The object of the invention is to provide an armchair which can be quickly converted from a conventional office armchair into a so-called knee armchair, also known as a "balance armchair". In practice, a balance armchair and a conventional office armchair are used alternately to load the muscle and skeleton parts more evenly over a working day. This object is achieved with an armchair of the type mentioned in the introduction, in which, according to the invention, the support arm consists of two parts which can be pivoted and locked relative to one another about an essentially horizontal axis.

In contrast to the known ones described above, the armchair according to the invention offers

Armchair constructions all the advantages of the well-known armchair with foot column, combined with a conversion option that is both constructive Effort and operation are extremely simple. Bulky constructions, such as are part of the state of the art, are avoided.

Further features of the invention emerge from the

Sub-claims emerge. The invention and its advantages are explained in more detail below using exemplary embodiments which are illustrated in the drawing. 1 shows an armchair according to the invention with its backrest in a first position of use in a schematic side view, FIG. 2 in a same view the armchair with its backrest in a second position of use, FIG. 3 in a partial view in the direction of the arrow of FIG Fig. 1 seat and back of the armchair according to Fig. 1, Figs. 4 to 7 in partial side view of a second embodiment of the invention in different phases of conversion from a knee chair into a conventional armchair, Fig. 8 and 9 in partial side view a third Variant of the invention and Fig. 10 in partial side view a fourth variant of the invention.

1, an armchair according to the invention consists of a foot 1, a foot pillar 2, a seat 3 arranged on the upper end of the foot pillar 2, and a backrest 4 which is supported or fastened to the foot pillar 2.

The foot column 2 is generally adjustable in height in a known manner by telescoping and can be locked in different positions. Here, the lower part 2a of the foot column 2 can be formed in one piece with the foot 1. The seat 3 is by means of a pivot bearing 5 to the Upper part 2b of the foot column 2 articulated and thus more or less tiltable to the front or back, whereby it can be locked in its tilted positions, for example by means of a strut 6, which can be locked in the manner not shown here on the foot 2, for example by means of a clamping screw or a pin-hole row connection.

The backrest 4 is fastened to the upper part 2b of the foot column 2 by means of a support arm 7. In the exemplary embodiment shown, the support arm consists of two parts 7a, 7b which can be pivoted relative to one another about an essentially horizontal axis al and which can be fixed in their mutual positions. This can e.g. by means of a fixable gas pressure spring 8. 1 shows a position in which the parts 7a, 7b run at right angles to one another; A position in which the part 7b is inclined to the rear by approximately 30 ° is shown in broken lines in order to give the backrest 4 a corresponding inclination.

The support arm part 7a is fastened to the upper part 2b of the foot column 2 by means of a rotary bearing 9 and can be rotated with respect to the part 7a about the axis s of the foot column 2, whereby it can be determined in two rotational positions different by 180 °, for example by latching or one Clamping screw (not shown).

The backrest 4 in this embodiment consists of a lower, larger part 4a and an upper, smaller part 4b. Both parts 4a, 4b are mutually adjustable about an essentially horizontal axis a2 and in their mutual positions, for example, by increased frictional force, but a complete locking is also conceivable.

In the embodiment shown, it is essential that the support arm 7 or its part 7a by one

Rotary bearing 9 located horizontal axis a3 can be pivoted downward by approximately 90 °, which is explained in more detail below.

The armchair according to the invention can be transformed from the shape shown in Fig. 1 into a knee chair. For this purpose, the support arm part 7a and the seat 3 are rotated about the pivot bearing 9 by 180 ° with respect to the foot column part 2b and then the entire support arm 7 together with the backrest 4 is pivoted downward about the axis a3 by 90 °. Now the upper backrest part 4b can be folded around the axis a2 and the inclination of the seat 3 around the pivot bearing 5 can be adjusted somewhat forwards in order to achieve the shape shown in FIG. 2, in which the backrest 4 instead of as in FIG 1 serves as a backrest, now as a knee or shin-rest. It is fixed about an axis a4, preferably at about 20 ° with respect to the horizontal, to adapt to the knee or shin after the load has been applied.

In addition to FIGS. 1 and 2, FIG. 3 shows a possible embodiment of the lower part 4a or the upper part 4b of the backrest 4 with the seat 3 in a partial view in the direction III in FIG. 1, the parts 4a and 4b around a substantially horizontal axis a2 are adjustable. The transformation of the chair from a knee chair into the usual shape shown in FIG. 1 and vice versa can also be carried out according to the steps shown in FIGS. 4 to 7. 4 shows a position which corresponds to the knee chair function according to FIG. 2. In Fig. 5 it is indicated by the arrow that in the embodiment shown in Figs. 4 to 7 it is provided that the seat 3 is designed to be displaceable and lockable with respect to the foot column 2, so that the armchair after the seat 3 has been set horizontally according to by subsequent displacement in the direction of the arrow and rotation through 180 ° about which the axis s can first be brought into the position shown in FIG. 6. The transition from the position shown in FIG. 6 to that according to FIG. 7 takes place by folding the support arm 7 up by 90 ° about the axis a3 and rotating the backrest 4 about the axis a4. For the sake of simplicity, the upper part 4b of the backrest 4, which can be rotated about the axis a2, has been omitted in FIGS. 4 to 7. However, such an upper part does not necessarily have to be provided, ie the back 4 can also be made in one piece or can also consist of more than two parts. According to the conversion possibility shown in FIGS. 4 to 7, one advantage of such an embodiment is in particular that a change of function can be carried out while sitting, whereby the armchair fulfills that of a real combination chair in addition to the function of a simple office work chair.

In a further embodiment according to FIG. 8, the support arm part 7b has a lockable swivel joint 10 which allows this support arm part to be rotated in itself, ie around its axis a5 by 180 °. As a result, the backrest 4 can move out of the usual positions shown in FIG be turned laterally by 180 ° into their lower knee chair position according to FIG. 9. In Fig. 9 it is indicated by further rotary arrows that the backrest 4 is adjustable about the axis a4 and that the support arm 7a can be rotated horizontally by means of the pivot bearing 9. In such an embodiment, the seat 3 does not have to be designed to be displaceable, as in FIG. 5, in order to be able to carry out a conversion corresponding to the positions in accordance with FIGS.

In a further embodiment according to FIG. 10, there is also no need to provide a sliding seat 3 for the above conversion. The figure shows schematically that the support arm 7 or at least one of the support arm parts 7a, 7b in this variant are adjustable in length, in particular telescopic, in order to obtain the desired relative position of the backrest 4 to the seat 3, the backrest 4 about the axis a4 is also rotatable.

The illustrated and described embodiments of the invention show how a chair can be quickly converted from one seat to the other, with a particular advantage being that the manufacturing cost of a

Combination chair according to the invention are only slightly higher than that of a conventional office chair.

Claims

1.

Armchair with a foot (1), a foot column (2), a seat (3) arranged on the foot column (2), the inclination of which is adjustable and with an adjustable arm supported at least on the foot column (2) by means of a support arm (7) Backrest (4), which rotates about at least one, essentially horizontal axis (a3, a1, a4, a5) from a first, essentially upright position of use located substantially above the seat level to a second position substantially below and essentially below the seat level lying position of use is adjustable, characterized in that the support arm (7) consists of two parts (7a, 7b) which can be pivoted and locked relative to one another about an essentially horizontal axis (a1, a5).

Second

Armchair according to claim 1, so that the support arm (7) can be rotated about the axis of the foot column (2) and can be locked in at least two rotational positions.

Third Armchair according to one of claims 1 or 2, characterized in that a support arm part (7b) has a lockable swivel joint

(10), which allows this support arm part to rotate about 180 ° about its axis (a5) (Fig.

9).

4. Armchair according to one of claims 1 to 3, so that the back (4) can be pivoted about a horizontal axis (a4) with respect to the support arm (7) or a support arm part (7b).

5th

Armchair according to one of claims 1 to 4, d a d u r c h g e k e n n z e i c h n e t that the support arm (7) or at least one of the

Support arm parts (7a, 7b) can be changed in length, in particular telescopically (FIG. 10).

6th

Armchair according to one of claims 1 to 5, so that the seat (3) is displaceable and lockable with respect to the foot column (2).

7.

Armchair according to one of claims 1 to 6, characterized in that the backrest (4) consists of at least two parts (4a, 4b) which are adjustable relative to one another about an essentially horizontal axis (a2).

8th.

Armchair according to one of claims 1 to 7, so that the seat (3) can be rotated with respect to the foot column (2) and can be locked in at least one rotational position.