EP1903912A1

EP1903912A1 - Synchronisation mechanism

Info

Publication number: EP1903912A1
Application number: EP06762117A
Authority: EP
Inventors: Hermann Bock
Original assignee: Bock 1 GmbH and Co KG
Current assignee: Bock 1 GmbH and Co KG
Priority date: 2005-06-26
Filing date: 2006-06-21
Publication date: 2008-04-02
Also published as: DE202005010097U1; CN100594823C; US20080136239A1; DE102005029906B3; CN101208029A; WO2007000270A1

Abstract

The invention relates to a synchronisation mechanism for a correlated seat and back rest movement of an office chair, said mechanism comprising a base support (1) that can be placed on a seat supporting post, a seat support (3), and a back rest support (4). The aim of the invention is to provide a synchronisation mechanism which does not necessitate the regulation of an elastic force in order to modify the pivoting resistance of the back rest. To this end, the back rest support (4) that can be pivoted about a transversal axis is connected to the base support (1) by means of a first connecting rod (7) and to the seat support (3) by means of a second connecting rod (25), in such a way that a pivoting movement of the back rest towards the rear induces a lifting movement of the rear region (32) of the seat support (3), and the seat support (3) is connected to the base support (1) in such a way that a lifting movement is performed simultaneously by the front region (37) of the seat support (3). The idea is based on the idea that the user of the office chair lifts him/herself up by putting pressure on the back rest.

Description

description

synchronous mechanism

The invention relates to a synchronous mechanism for a correlated seat-backrest movement of an office chair, with a placeable on a chair column base support, a seat support and a backrest support.

The term "synchronous mechanism" is understood to mean assemblies in the seat substructure of an office chair which provide kinematics which are coupled to one another and provide a specific relative movement of the seat and backrest The backrest support, which extends in a conventional manner from the actual synchronizing mechanism to the rear, carries on an upwardly extending arm, the backrest of the office chair.Seat carrier and backrest support are usually coupled so articulated that a pivoting movement of the backrest to the rear - like can be caused for example by a leaning of the chair user to the backrest - induced a lowering movement of the rear edge of the seat down.

In order to change the "pivoting resistance" of the backrest, such synchronous mechanisms usually have a spring arrangement for preloading the synchronizing mechanism, the strength of the prestressing being dependent, inter alia, on the weight of the chair user. German Offenlegungsschrift 2026 929 discloses a chair with automatically adapting backrest, in which the rear part of the seat panel raises when the user leans against the backrest and thus pivots it backwards. This is achieved in that a handle designed as a lever end of the backrest support is constantly applied to the underside of the seat plate. When lowering the seat plate, the backrest moves forward. If the user leans against the backrest, the rear part of the seat is raised.

An object of the present invention is to provide a synchronous mechanism in which a setting of a spring force for changing the "pivoting resistance" of the backrest is not required.

This object is achieved by a synchronous mechanism according to claim 1. Thereafter, it is provided that the pivotable about a transverse axis backrest support is connected on the one hand via a first link to the base support and on the other hand via a second link to the seat support such that a pivoting movement of the back to the rear induces a lifting movement of the rear portion of the seat support. At the same time the seat support is connected to the base support such that a lifting movement of the front portion of the seat support takes place.

A basic idea of the invention is that the user of the office chair "raises" himself by stressing the backrest itself, in other words, when the synchronous mechanism is operated by pushing the backrest back, the user works against his own weight resting on the seat. The desired "swivel resistance" thus sets itself, as it were, automatically on the basis of the weight of the user. From the prior art known spring force settings with elaborate adjustment mechanisms (worm gears, gears, threaded rods, etc.) are not required. This considerably reduces the manufacturing costs of the synchronous mechanism. At the same time, the reliability increases.

Characterized in that the seat support is not only raised in its rear region, but at the same time also takes place a lifting of the front portion of the seat support, synchronous entrainment of the seat takes place in a defined relationship to the backrest to the rear top.

Advantageous embodiments of the invention are specified in the subclaims.

It when the base support is connected to the front end portion of the seat support via a linear guide is particularly advantageous. In this case, there is a linear synchronous movement of the seat with the backrest. In addition to guides with linear guideways other guideways are of course possible. Due to the design of the guide, the position of the guide (for example, the inclination angle of the guide to the horizontal), etc., the synchronous movement of the seat support can be adjusted individually. Thus, for example, it is possible for the seat support to move absolutely linearly synchronously with the backrest without a "tilting." However, a corresponding design of the guide also makes "tilting" possible. Other variants can be achieved in that the connection point between the base support and seat support is mounted more or less far away from the front seat edge.

The required for the "self-adjusting" mechanics of the present invention lever geometry is achieved by the arrangement and design of the two links, wherein preferably the first link is provided with a pivot bearing for producing a pivotal connection with the base support, and wherein the handlebar end with the seat support and The relative movement of the seat support and backrest support to each other, the opposite bar end is hinged to the backrest support is thus defined by the position of the total four extending through the ends of the two links joint axes. At the same time, the displacement of the seat support to the base support is defined on the one hand by the linear guide in the front region of the seat support and on the other hand by the position and function of the pivot bearing on the first link.

It is particularly advantageous if the first link and / or the second link are covered to the outside by a part of the backrest support and / or a part of the seat support. By such a hidden arrangement "inside" the synchronizing mechanism dirt and damage to the pivot mechanism can be prevented.

Compared with those known from the prior art

Solutions according to the invention a structurally comparatively simple pivot mechanism is presented, with which the so-called "shirt extraction effect" is significantly reduced. In other words, a particularly high level of comfort is achieved, without having to resort to more expensive and expensive solutions.

An embodiment of the invention will be explained in more detail with reference to the drawings. Hereby show:

Fig. 1 is a perspective view of a synchronous mechanism obliquely from behind, Fig. 2 is a side view of the synchronous mechanism in the

Basic position and Fig. 3 is a side view of the synchronous mechanism in a pivoted backward position. All figures show the synchronous mechanism only schematically with the essential components of the invention.

The synchronous mechanism has a base support 1, which is set by means of a cone holder 2 on the upper end of a chair column (not shown), see Fig. 1. In addition, the synchronous mechanism comprises a substantially frame-shaped seat support 3 and a fork-shaped in plan view backrest support 4, whose cheeks 5, 6 are arranged on both sides of the base support 1. The seat support 3 is provided for receiving or mounting a preferably padded seat (not shown). The assembly is done using not shown fasteners in the usual way. At the

Backrest support 4 is attached to a backrest, not shown, which is height adjustable in modern office chairs. The backrest can also be integrally connected to the backrest support 4.

As is clear from the figures, the entire synchronous mechanism with respect to the central longitudinal plane M, as far as the actual kinematics is concerned, constructed mirror-symmetrically. In that regard, in the following description is always based on both sides in pairs existing construction elements of the actual pivot mechanism.

In the figures 1 and 2, the basic position is shown, in which the backrest support 4 assumes a substantially vertical position. Fig. 3 shows the synchronizing mechanism in a rearwardly pivoted position. The backrest support 4, which is pivotable about a transverse axis in the pivoting direction S, is connected to the base support 1 via a first link 7. In this case, the first link 7 is provided with a pivot bearing 8 for producing a pivotal connection with the base support 1. The handlebar 7 is articulated by means of a bearing pin 9 on a side leg 11 of the base support 1 extending in the direction of the seat trailing edge 10. The one free end 12 of the first link 7 is articulated via a hinge 13 with a side arm 14 of the seat support 3 extending in the direction of the seat trailing edge 10. The opposite free end 15 of the handlebar 7 is pivotally connected via a hinge 16 with a extending in the direction of the seat leading edge 17 cheek 5, 6 of the backrest support 4. The side arm 14 of the seat support 3 also runs parallel to the

Side leg 11 of the base part 1 as to the cheek 5, 6 of the backrest support 4. While side arm 14 and cheek 5, 6 are arranged substantially in alignment, the side legs 11 extends toward the chair center M offset to the side arm 14. The first arm 7 extends Thus, between the side legs 11 of the base support 1 on the one hand and the side arm 14 of the seat support 3 and the cheek 5, 6 of the backrest support 4 on the other.

Defined by the articulation of the lower end 15 of the handlebar 7 on the backrest support 4 first hinge axis 18 is seen in the chair longitudinal direction 19 behind the defined by the articulation of the upper end 12 of the arm 7 to the seat support 3 second hinge axis 20. The angle α of the first link 7 to the horizontal in the normal position is about 5 °. Even in a maximum rearwardly pivoted position of the synchronous mechanism, this order of arrangement of the joint axes 18, 20 changes Not. In the rearwardly pivoted position, as shown in Fig. 3, the first link 7 also shows obliquely forward, but then it includes with the vertical an angle ß of about 12 °. In addition, the first articulation axis 18 always extends below the second articulation axis 20 when viewed in the vertical direction.

The pivot bearing 8 is arranged outside the middle of the handlebar, namely slightly offset in the direction of the second hinge axis 20 out. The running through the pivot bearing 8

Pivot axis 21 extends parallel to the two hinge axes 18, 20. According to the course of the hinge axis 18, the two lower ends 15 of the two first link 7 of the synchronizing mechanism are connected to a holding axis 22 whose ends designed as a journal serve to form the joints 16. At the same time, a defined pivoting of the first link 7 is thereby secured and tilting of the link 7 is avoided.

At this point it should be pointed out once again that the components of the swivel mechanism are each double. However, for example, in Fig.l only the arranged on the right side 23 of the seat first link 7 is shown, while on the left side 24 of the seat existing first link is covered by the cheek 6 of the backrest support 4.

In addition, the backrest support 4 is connected via a second link 25 to the seat support 3. The first link 7 is slightly longer than the second link 25. The length ratio between the (rear) first link 7 and the (front) second link 25 is about 1.07: 1. The one free end 26 of the second link 25 is in turn via a joint 27 with the side arm 14 of the seat support 3 and the opposite free end 28 of the handlebar 25 via a joint 29 with the cheek 5, 6 of the backrest support 4 hingedly connected. Defined by the articulation of the lower end 28 of the second link 25 on the backrest support 4 third hinge axis 30 is arranged in the chair longitudinal direction 19 behind the defined by the articulation of the upper end 26 of the handlebar 25 to the seat support 3 fourth hinge axis 31. This means that the second link 25 in the basic position of the synchronous mechanism a

Inclination from the bottom rear to the front above, cf. Fig. 2. In this case, the angle γ of the second link 25 to the horizontal about 52 °. In the rearwardly pivoted position, as shown in Fig. 3, the second link 25 but obliquely backwards, namely at an angle δ of about 24 ° to the vertical, while the first link 7 is still pointing obliquely forward. In other words, the fourth hinge axis 31 is in this position behind the position of the third hinge axis 30, that is further displaced towards chair rear edge 10.

The vertical arrangement of the joint axes 30, 21 of the second link 25 corresponds to the principle according to the vertical arrangement of the joint axes 18, 20 in the first link 7. The third hinge axis 30 thus extends in vertical

Direction always below the fourth hinge axis 31st

The vertical arrangement of the four hinge axes 18, 20, 30, 31 of the first and second links 7, 25 is as follows: the second and fourth hinge axes 20, 31 are substantially at a height in both the home position and the pivoted position , The pivot axis 21 of the first link 7 always runs between the height of the second or fourth hinge axes 20, 31 and the height of the first and third hinge axes 18, 30. The first hinge axis 18 is in the basic position between the pivot axis 21 and the third hinge axis 30 and in the pivoted position below the fourth hinge axis 31st

By the described pivot mechanism ensures that the backrest support 4 can be pivoted to the backrest about a pivot axis in the pivoting direction S. At the same time, the

Pivoting movement S of the backrest to the rear, a lifting movement Hl of the rear portion 32 of the seat support 3, see. In a pivoting of the backrest to the rear bottom is in other words a displacement of the seat support 3 backwards and upwards, while the base support 1 with the pivot bearing 9 remains fixed in position.

In the area of the first and second links 7, 25, in which the cheek 5, 6 of the backrest support 4 and the

Meeting side arm 14 of the seat support 3, the lower edge of the side arm 14 running from the top rear to the bottom lies against the likewise running top edge 34 of the cheek 5, 6 in a defined contact region and thus secures the basic position of the synchronizing mechanism. To the slope, an area is added to the rear, in which the substantially vertically extending free end 35 of the side arm 14 and the correspondingly shaped end face 36 of the cheek 5, 6 face each other. By this arrangement, a closed cover is formed, which is the underlying

Lever construction protects against contamination. By a simple additional cover, for example in the form of an extension of the cheeks 5, 6 of the backrest support 4 Above, can be achieved beyond that even in the pivoted state penetration into the swing mechanism can be safely excluded. Thus, a high degree of security in the handling of the office chair can be created.

At the same time, the seat support 3 is connected to the base support 1 in such a way that a lifting movement H2 of the front area 37 of the seat support 3 takes place with a pivoting of the backrest support 4. In the embodiment, the

Synchronous mechanism carried out such that the rear portion 32 of the seat support 3 is raised slightly more than the front portion 37 of the seat support 3 (Hl> H2), so that from the substantially flat position of the seat support 3 in the basic position slightly forward inclined

Position of the seat support 3 in the pivoted position results. This avoids unwanted constrictions or pressure on the underside of the thighs during pivoting. In the pivoted position of the backrest support 4 is pivoted about a pivot angle ε of about 24 ° to the base support 1, while the seat support 3 is raised almost parallel. In the embodiment (Hl> H2), the rear portion 32 of the seat support 3 is raised relative to the front portion 37 of the seat support 3 by an angle φ of about 2 °.

The base support 1 is connected to the seat support 3 via a linear guide in the manner of a slot-like link 38, which is arranged in the front region 37 of the seat support 3. The base support 1 has two laterally arranged and in the direction of the seat leading edge 17 extending wings (not shown). These are connected to each other via a bearing axis. The bearing axis is parallel to the hinge axes 18, 20, 30, 31, the pivot axis 21 and the support shaft 22 is arranged. The two formed as a bearing pin 39 ends of the bearing axis are each from the inside in the gate 38, which serves as a linear sliding guide. The gate 38 is formed in a side member 40 of the seat support 3, which extends in the direction of the seat leading edge 17. The gate 38 extends obliquely from the front bottom to the rear top and closes with the horizontal in the pivoted position an angle η of about 42 ° (basic position about 40 °). In the basic position of the synchronizing mechanism, the ends 39 of the bearing axis abut the upper stop of the link 38. The bearing axis is then located approximately at a height with the second and fourth hinge axis 20, 31. When pivoting takes place by raising the seat support 3 is a shift of

Bearing axis in the direction of the opposite lower end of the link 38. The bearing axis is then located approximately at a height with the pivot axis 21st

Due to this construction, not only the rear portion 32 of the seat support 3 performs a lifting movement Hl when the seat back is loaded and the seat back support 4 performs pivotal movement in the swinging direction S rearward downward. In addition, the front portion 37 of the seat support 3 in a synchronous manner linearly lifted (lifting movement H2). In other words, there is a simultaneous lifting movement of the front and the rear end of the seat. The seat in its entirety is raised.

In addition, the synchronizing mechanism comprises a in the basic position substantially horizontally arranged in the seat support 3 spring element in the form of a tension spring 41, which is connected on the one hand with the bearing axis of the base support 1 and on the other hand with a further transverse holding axis 42 on the seat support 3. The tension spring 41 is mounted with its front end to the bearing axis and with its rear end to the support shaft 42. The tension spring is for

Initial position of the synchronizing mechanism biased. In the basic position, the arranged between the side legs 11 of the base support 1 holding axis 42 is approximately at the height of the bearing axis and the second and fourth hinge axis 20, 31. In the pivoted position, the support shaft 42 with the seat support 3 with backwards and upwards taken and is then also approximately at the height of the second and fourth hinge axis 20, 31. In this case, the distance between the bearing axis and support shaft 42 and the then obliquely rearwardly upward extending tension spring 41 is further stretched. With this spring tension, the return of the backrest from the pivoted position is supported in the normal position. Instead of a single tension spring 41, depending on the type of load provided for the chair, several springs parallel or other spring elements can be used. To determine the backrest inclination a mechanism not further explained is provided which can be operated by means of an actuating lever (not shown).

LIST OF REFERENCE NUMBERS

1 base carrier

2 cone holder

3 seat support

4 backrest support

5 cheek

6 cheek 7 first handlebar

8 pivot bearings

9 journals

10 seat trailing edge

11 side legs

12 free

13 joint

14 side arm

15 free

16 joint

17 seat leading edge

18 first joint axis

19 chair longitudinal direction

20 second hinge axis

21 pivot axis

22 holding axis

23 right side

24 left side

25 second handlebar

26 free

27 joint

28 free

29 joint

30 third hinge axis

31 fourth joint axis

32 rear area

33 lower edge

34 top edge

35 free

36 face

37 Front area

38 scenery

39 cones Side element tension spring holding axis

Claims

claims

Synchronous mechanism for a correlated seat-backrest movement of an office chair, with a placeable on a chair column base support (1), a seat support (3) and a backrest support (4), wherein the pivotable about a transverse axis backrest support (4) on the one hand via a first link (7) to the base support (1) and the other via a second link (25) with the seat support (3) is connected such that a pivoting movement of the backrest to the rear of a lifting movement (Hl) of the rear portion (32) of the seat support (3) induced and wherein the seat support (3) with the base support (1) is connected such that at the same time a lifting movement (Hl) of the front portion (37) of the seat support (3).

2. Synchronous mechanism according to claim 1, wherein the base support (1) with the seat support (3) via a guide (38), in particular a linear guide is connected, which is preferably arranged in the front region (37) of the seat support (3).

3. synchronizing mechanism according to claim 1 or 2, wherein the first link (7) with a pivot bearing (8) is provided for producing a pivotal connection with the base support (1), and wherein the one handlebar end (12) with the seat support (3) and the opposite bar end (15) is pivotally connected to the backrest support (4).

4. Synchronous mechanism according to one of claims 1 to 3, wherein the first link (7) and / or the second link (25) are covered to the outside by a part of the backrest support (4) and / or a part of the seat support (3) ,