EP1060694A1 - Chair, particularly office-chair - Google Patents

Abstract

The adjustable frame for an office chair (1) has a seat support frame (2) rotatable about a first pivot point (8) which also form a pivot for a lowerable backrest (6). The backrest has a second pivot (12) to allow synchronised movement with the squab (10). The first pivot point is higher, in the rest position o the backrest than the second pivot which can be in the same plane as the squab.

Description

The invention relates to a chair, in particular an office chair, with one in reference arranged on a seat support rotatable about a first pivot a rest position reclining backrest, and one with the backrest rotatably connected about a second pivot point, synchronized with the backrest reclining seat.

Such a chair is for example from the European patent application EP 0 888 739 A2 is known. In the known chair are both the backrest as well as the seat rotatably connected to it from a rest position designed to tilt backwards. The one running in a vertical plane of movement Tilt movement is from a linkage in the form of a four-swivel chain controlled as a guide gear. Make one with a pedestal connected seat support a basic control arm and the one above it in approximately parallel position trending seat a handlebar.

These handlebars are at their ends each via a front link and one Return links connected to form the four-swivel chain. The The rear link is fixed to the backrest in relation to the inclination movement connected so that the first pivot through the axis of rotation between the Seat support or base link and the rear link is given. In corresponding The second pivot point is by the axis of rotation between the return link and given the seat or the handlebar.

A chair is known from EP 0 250 207 B1 in a similar manner Tilting movement of the backrest and the seat that is guided synchronously with it controlled via a four-swivel chain. With this chair it is the tilting movement of the chair controlling four-swivel chain from one with their ends on the front joint of the seat link and on the base of the gas pressure spring applied to the seat link each from a backward tilt position to return to the rest position.

A chair of the type mentioned at the outset is also known from PCT WO 83/00610. This chair is used as a guide gear for the inclination movement also a coupling gear, but in the form of a Kurbei loop, i.e. a three-link chain with two swivel joints and one swivel-thrust joint. In this chair, too, a gas pressure spring releases the seat link a backward tilt position to the rest position. The one with her one end is attached to the base or seat support by a compression spring with its other end at the rear joint of the seat handlebar, where this with the the backrest carrying back link is connected.

The invention has for its object a chair of the type mentioned to further develop such that a particularly far-reaching inclination movement the backrest with an inclination of, for example, up to 40 ° to the starting position of the backrest - is possible without the chair tilts back over its center of gravity. Furthermore, it should also be special large backrest inclination of more than 40 ° largely avoided be that a person sitting on the chair has the feeling of being soon Experiences overturning.

This object is achieved in that the first pivot point in the rest position is positioned at approximately the same height or higher than or as the second pivot point.

The invention is based on the consideration that in the known chairs this tends to tilt and the achievable angle of inclination Backrest is therefore limited by the fact that the center of gravity of the chair is the inclination of the backrest to the rear in a particularly strong degree as well is shifted backwards. This is particularly reinforced by the fact that an inclination of the backrest back and down which is synchronized with this guided seat is also moved to the rear. For a minor one The chair should be inclined to tilt so that even with one stronger inclination of the backrest the center of gravity in only a small amount Dimensions is shifted backwards. A shift of focus to rear can be kept particularly low by the inclination of the Backrest backwards a synchronous shift of the seat not behind, but rather to the front. This is due to the arrangement mentioned of the first and the second pivot point relative to each other.

The chair is advantageously designed in such a way that during an inclination movement the backrest back and down the second pivot moved forward and down. An inclination of the backrest backwards and goes down with a shift of the seat forward and with a lowering of the seat. Relatively speaking, the moves (with respect to the seat support stationary) first pivot point in relation to the seat surface up, whereas the second pivot point down towards moved the seat support. With such an arrangement, the sequence of movements particularly pleasant for the person using the chair during inclination be designed.

For a particularly simple construction, the chair is also useful designed so that the second pivot point at the level of the seat and thus the through this defined axis of rotation between the seat and backrest in the Seat lies.

In a further advantageous embodiment, the first pivot point is higher than the lower edge the seat. For a particularly pleasant sensation of movement the person using the chair is also in a further practical configuration the second fulcrum to recreate the body's own fulcrums in the rest position about one for the ischial bones of the seated Person intended position arranged.

In a particularly advantageous embodiment, the chair is designed such that the inclination movement the synchronous relationship between the seat and Backrest is approximately 1: 3. With an inclination of the backrest of approximately 40 ° there is thus an inclination of the seat surface with respect to its starting position of about 13 ° or 14 ° from their starting position, the inclination advantageously results from a corresponding lowering of the seat.

For a particularly ergonomic design, the seat is especially with regard to their dimensions in relation to the position of the first and the second fulcrum, appropriately dimensioned such that when the backrest is tilted back and forth below the front edge of the seat moved forward and down.

For mechanical support and to tilt the seat enable, this seat with the seat support is conveniently one third pivot point rotatably connected. In order for the inclination movement of the Backrest intended movement of the seat forwards and downwards to enable the third pivot point is expediently positively guided. The positive guidance is advantageously designed such that a Backrest tilting back and down the third Pivot point moved forward and downward. By dimensioning the Forced guidance is the synchronous relationship between the seat and the Backrest and the extent of the forward movement of the seat at the Adjustable backrest inclination.

For a particularly simple construction, the third pivot point is forced a guided tour provided. One defined by the third pivot The axis of rotation can be physically positioned at a suitable location on the Arranged seat, with their ends facing beyond the seat Turning rod can be realized, the ends of which are positively guided in the backdrop. In this Embodiment is as a guide gear for the inclination movement a coupling gear provided in the manner of a three-swivel chain with link guide. As an alternative, the third pivot point can also be moved around on the seat support a fourth pivot point rotatably arranged arm.

The advantages achieved with the invention are in particular that the positioning of the first pivot point in the rest position at approximately the same height or higher than the second pivot point is ensured in a particularly simple manner is that when the backrest is tilted backward, it moves forward the seat is done. This was done by tilting the backrest backwards Shifting the center of gravity of the chair backwards is thus caused by the Movement of the seat to the front at least partially compensated. As a result shows the chair even when the backrest is particularly far inclined only a particularly low tendency to tip over.

In addition, it is ensured by such an arrangement that that on the chair seated person with an inclination of the backrest not in the manner of falling over tilted completely backwards, but rather in the manner of a rotation around a body's own pivot point without major lateral displacement into one inclined position is brought. A comparatively strong inclination is therefore the Backrest with synchronous inclination of the seat enables without the seated person experiences the feeling of tipping over soon.

The guidance of the third pivot point in a setting also enables the setting one that is particularly pleasant for the movement Synchronous ratio between seat and backrest of about 1: 3 simultaneous lowering of the front edge of the seat surface during the recline the backrest.

Fig. 1

in schematischer Seitenansicht einen Bürostuhl in Ruheposition,

Fig. 2

den Bürostuhl gemäß Fig. 1 in nach hinten zurückgeneigter Endstellung,

Fig. 3

überlagert die Darstellungen des Bürostuhls gemäß den Figuren 1 und 2,

Fig. 4

in schematischer Seitenansicht eine alternative Ausführungsform eines Bürostuhls in Ruheposition,

Fig. 5

den Bürostuhl gemäß Fig. 4 in nach hinten zurückgeneigter Endstellung, und

Fig. 6

überlagert die Darstellungen des Bürostuhls gemäß den Figuren 4 und 5.

Exemplary embodiments of the invention are explained in more detail below with reference to a drawing. In it show:

Fig. 1

a schematic side view of an office chair at rest,

Fig. 2

1 in the end position tilted backwards,

Fig. 3

overlays the representations of the office chair according to FIGS. 1 and 2,

Fig. 4

a schematic side view of an alternative embodiment of an office chair in the rest position,

Fig. 5

4 in the end position tilted backwards, and

Fig. 6

overlays the representations of the office chair according to FIGS. 4 and 5.

Corresponding parts are given the same reference numerals in all figures Mistake.

The chair 1 designed as an office chair according to FIGS. 1, 2 comprises a fixed one with a stand carrier, not shown, connected 2. With the Seat support 2 is rotatably connected to a backrest 6 via an axis of rotation 4. The backrest 6 is from the rest position shown in FIG tiltable at the back. The backrest 6 is inclined by rotation around a first pivot point 8, which is essentially through the central axis of the Axis of rotation 4 is given.

With the backrest 6 there is a seat surface 10 about a second pivot point 12 rotatably connected, in the embodiment, the second pivot point 12 is by the Given the central axis of a fastener, not shown, which the Seat 10 physically connects to the backrest 6. In terms of its lateral Position is the second pivot point 12 in the rest position of the chair 1 approximately below the position that the ischial bones one in the chair 1 ingested person.

As shown in Figure 1, the first pivot 8 is in the rest position of the chair 1 positioned slightly higher than the second pivot point 12. Alternatively, the first pivot point 8 but also at about the same height or significantly higher than the second pivot point 12 may be arranged. The second is in the exemplary embodiment Pivot point 12 in the seat surface 10, so that the first pivot point 8 is also above the lower edge 13 of the seat 10 is arranged.

The seat 10 is for one with an inclination movement of the backrest 6 synchronous inclination movement. A occurring rotation of the Seat 10 relative to the orientation of the seat support 2 is over a third pivot point 14 characterized. The third pivot point 14 is physical in the exemplary embodiment realized in an axis of rotation 16 arranged below the seat surface 10. The axis of rotation 16 and with this the third pivot point 14 are in one on the seat support 2 arranged backdrop 18 positively guided.

As can be seen particularly in the comparative illustration according to FIG the chair 1 is designed such that when the backrest is tilted 6 to the rear (and thus also downwards) the second pivot point 12 moved forward and down. An inclination of the backrest to the rear thus results in both a forward movement of the seat surface 10 as well as lowering them. The resulting inclination of the seat 10 is thereby due to the inclination movement and its guidance in the Setting 18 occurring change in position of the third pivot point 14 is determined. When the backrest 6 is inclined backwards, the third moves Pivotal point 14 due to its positive guidance in the backdrop 18 to the front and downward.

The backdrop 18 is in relation to the positioning of the pivot points 8, 12 and 14 dimensioned such that the synchronous ratio with respect to the inclination movement between the seat surface 10 and the backrest 6 is approximately 1: 3. With in other words: the angle of inclination swept by the backrest 6 at its inclination is about three times the angle around which the seat is 10 when moving tends.

To reset from the backward tilt position of the backrest 6 is in the rest position, the chair 1 with a suitable not shown Spring system, for example with a conventional one, arranged in or on the seat support 2 Gas spring, provided.

The chair 1 'in the exemplary embodiment according to FIGS. 4 to 6 also has the chair 1 has a positively driven axis of rotation 16 and thus a positively driven one third pivot point 14 between the seat surface 10 and the seat support 2. At the Chair 1 ', however, is an arm 20 for the forced guidance of the third pivot point 14 intended. The arm 20 acts on the third pivot point 14 and is in turn arranged with the seat support 2 rotatable about a fourth pivot point 22. With regard to its dimensioning, the arm 20 is also dimensioned such that that the synchronous relationship between the Seat 10 and the backrest 6 is about 1: 3.

Each of the chairs 1,1 'is due to the arrangement of the pivot points 8, 12 to each other suitable for a particularly large angle of inclination of the backrest 6. The achievable inclination of the backrest can be, for example, up to 40%, without tipping over. According to the synchronous ratio between the seat 10 and the backrest 6 of about 1: 3 occurs at an incline the backrest 6 by about 40 ° with respect to the starting position of the backrest 6 an inclination of the seat surface 10 due to its lowering by approximately 13 ° or 14 ° from the starting position of the seat 10. For that Person using chair 1, 1 turns up despite the comparatively strong Inclination a particularly pleasant feeling of movement, as a result of the opposite lateral movements of the backrest 6 and seat 10 only one comparatively slight shift of the center of gravity to the rear occurs. The pleasant impression of movement is further enhanced by the fact that the seat surface 10 is dimensioned in such a way that when the backrest 6 is tilted backwards and downwards Front edge 24 of the seat surface 10 as well as this overall forward and moved down.

Reference list

1.1 '

chair

2nd

Seat support

4th

Axis of rotation

6

backrest

8th

first pivot point

10th

Seat

12th

second pivot point

13

Lower edge

14

third pivot point

16

Axis of rotation

18th

Backdrop

20th

poor

22

fourth pivot point

24th

Front edge of the seat 10

Claims (11)

Chair (1, 1 '), in particular office chair, with a backrest (6) which can be rotated about a first pivot point (8) with respect to a seat support (2) and which can be tilted from a rest position, and with one with the backrest (6) a second fulcrum (12) which is rotatably connected and which can be tilted synchronously with the backrest,
characterized,
that the first pivot point (8) is positioned in the rest position at approximately the same height or higher than or as the second pivot point (12). Chair (1,1 ') according to claim 1,
characterized,
that when the backrest (6) tilts backwards and downwards, the second pivot point (12) moves forwards and downwards. Chair (1, 1 ') according to claim 1 or 2,
characterized,
that the second pivot point (12) lies at the level of the seat surface (10). Chair (1,1 ') according to one of claims 1 to 3,
characterized,
that the first pivot point (8) is higher than the lower edge (13) of the seat surface (10). Chair (1,1 ') according to one of claims 1 to 4,
characterized,
that the second pivot point (12) is arranged in the rest position approximately below a position provided for the seat bones of a seated person. Chair (1,1 ') according to one of claims 1 to 5,
characterized,
that the synchronous ratio between seat surface (10) and backrest (6) is approximately 1: 3 with respect to an inclination movement. Chair (1,1 ') according to one of claims 1 to 6,
characterized,
that when the backrest (6) tilts backwards and downwards, the front edge (24) of the seat surface (10) moves forwards and downwards. Chair (1,1 ') according to one of claims 1 to 7,
characterized,
that a third pivot point (14) defined as the pivot point between the seat surface (10) and the seat support (2) is positively guided with regard to an inclination movement of the backrest (6). Chair (1,1 ') according to claim 8,
characterized,
that when the backrest (6) tilts backwards and downwards, the third pivot point (14) moves forwards and downwards. Chair (1) according to claim 8 or 9,
characterized,
that the third pivot point (14) is positively guided in a backdrop (18). Chair (1 ') according to claim 8 or 9,
characterized,
that the third pivot point (14) is positively guided via an arm (20) which is arranged on the seat support (2) and is rotatable about a fourth pivot point (22).

Images