EP1440632B1 - Chair with quick-adjustable force accumulator - Google Patents

Abstract

The working chair has an energy storing device with a front end rotatably mounted on the free swiveling end of a guide bar. The rear end of the energy storing device is engaged with the end of a backrest support at an adjustable contact point.

Description

The invention relates to a chair with rapidly adjustable energy accumulator according to the preamble of patent claim 1.

With the subject matter of EP 0 277 474A1 a chair has become known in which the seat part is mounted by means of a parallelogram handlebar assembly against the bias of a spring element height-adjustable on the seat support. The backrest support is pivotally mounted on the seat support, wherein a pivoting of the backrest support takes place against the biasing force of the spring element. However, it is not possible to manually influence the biasing force of the spring element.

With the subject matter of DE 198 10 768 A1, a further synchronizing mechanism has become known, in which a force accumulator not prestressed by the backrest support in the form of a helical compression spring is present. In this known arrangement, the bias of the helical compression spring can be changed by a mechanical gear, which is acted upon by a hand-rotatable knob.

It is accordingly a synchronous mechanism in which the spring force of the helical compression spring can be adjusted by a manual adjustment.

When swinging the backrest support the seat plate is guided over an obliquely backward directed slot to the rear, whereby the spring is tensioned. Thus, there is the disadvantage of a relatively difficult guidance between the seat and the backrest support and, moreover, the further disadvantage that the manual adjustment of the spring preload force by a spur gear is complex and prone to failure.

With the own DE 35 37 203 A1 a work chair with tilt mechanism of seat and backrest is disclosed, both of which are arranged on a seat support in the same direction and pivotally dependent on each other, wherein in the seat support a force element with an adjustable in its longitudinal extent Blocking element is arranged and the seat pan and the backrest spring-loaded pivoted into the rest position, wherein the force accumulator has two parallel compression springs with a blocking element mounted therebetween and one end of the force element is pivotally connected to the free, pivotable part of a lever arm, which is part of the the backrest is connected backrest support.

EP 1 258 211 A3 discloses a synchronous mechanism for a simultaneous seat surface and backrest pivoting movement in office chairs which has a spring arrangement with integrated spring force adjustment arrangement, wherein the spring arrangement comprises a pivotable bearing block, an abutment link articulated in the bearing block the compression spring back rests support side and a manually operated control mechanism is provided.

With the above. Document DE 198 10 768 A1 discloses an office chair with synchronous mechanism, which has a non-restraint biased energy storage in the form of a helical compression spring, wherein the bias of the helical compression spring is changed by a mechanical transmission, which is acted upon by a hand-rotatable knob.

The invention is therefore the object of developing a chair with adjustable by the user energy storage so that a much simpler adjustment of the energy storage can be done.

To achieve the object is provided in the invention that on the pivotable part of the backrest support a locking member is arranged, which consists essentially of a rack. The recesses of this rack are directed against the energy storage, which is engageable with an associated spring guide and arranged at the rear end of the spring guide tooth into engagement with the recesses of the rack of the locking member.

With the given technical teaching, there is the advantage over the prior art that no longer a direct adjustment of the bias of the energy storage by a spur gear or the like, but that the setting of the energy storage by pivoting the point of the energy accumulator on the pivotal part of the backrest support he follows.

It is important now that the pivoting of the energy accumulator (designed here as a helical compression spring) can be adjusted by hand. For this purpose, an externally accessible lever is provided which is non-rotatably connected to a tab in which a slot is arranged. In this slot, the spring guide of the energy storage is guided. If the lever is pivoted manually, then the tab and the slot incorporated in the tab is pivoted, whereby the spring guide is adjusted in this slot and the spring is more or less pivoted about its front pivot bearing.

In this way, a sensitive adjustment of the spring force on the backrest support is possible because the arranged on the locking part rack has a diverse subdivision. For example, a number of eight to thirty different latching recesses may preferably be arranged along the length of the rack, these latching recesses interacting in each case with one or more teeth of the spring guide of the energy accumulator.

It is important that there is no need for locking the pivoting of the manually pivotable lever, because it is an automatic locking of the set position. Thus, as soon as the backrest side end of the energy accumulator is locked with its teeth in the associated teeth on the locking part of the backrest support independently by the lowering of the backrest support, it requires no further locking for the hand-pivoting lever more. This saves significant design and manufacturing costs.

In contrast to so-called "full automatic" according to the prior art is no longer provided in the invention that the seat plate itself is designed to be pivotable. So it does not cause adjustment of the spring, but according to the invention the spring is changed by a hand-adjustable lever in its point of force application on the backrest support. This significantly reduces the manufacturing costs.

It is customary to date that the front end of the force accumulator (eg the helical compression spring) is supported on a housing-fixed point of the seat support. The invention refrains from this and provides that this front point is now arranged on the pivotable part of a link which is arranged on the foremost edge of the seat carrier.

This link pivots in the same way as the backrest support pivots when the user leans against the backrest support. In order to the front end of the force accumulator is additionally biased against the rear, lean-side end of the force accumulator, whereby an additional bias of the energy accumulator takes place. This is so biased in a double manner when pivoting down the backrest support, namely once by the movement of the pivotal part on the seat, namely the backrest end of the force accumulator, and on the other hand, the force accumulator is independently of this additionally additionally compressed by the fact that the front end of the force accumulator attaches to said handlebar, which is also pivotable in the direction of the back-swinging backrest carrier.

Incidentally, the invention also provides that a pre-positioning of the latching tooth or of the latching teeth of the energy accumulator in relation to the rack is made on the latching part. Such pre-positioning always ensures that when pivoting the backrest support is always a locking tooth of the energy storage of an associated recess on the locking member opposite. This unwanted scratching and scraping noises are avoided when making the locking connection.

The invention achieves this by providing an indexing pin at the free, pivotable end of the energy accumulator, which engages in an associated indexing rail in a spring-loaded manner. This indexing rail therefore specifies different pivoting angles of the energy accumulator before it is even engaged in the latching recess on the locking part. In this way, it is always ensured that the locking tooth on the energy storage is always in juxtaposition to a corresponding recess on the locking part.

The invention provides in another embodiment, a stepless locking, because it is readily possible, the engagement between the energy storage and the associated locking member as a sliding guide execute, which can be locked in certain places (for example by means of an eccentric).

A stepless engagement of the lean side end of the force accumulator in the associated locking member is hereby expressly claimed.

The subject of the present invention results from the subject matter of the claims.

All information and features disclosed in the documents, including the abstract, in particular the spatial design shown in the drawings, are claimed to be essential to the invention insofar as they are novel individually or in combination with respect to the prior art.

In the following the invention will be explained in more detail with reference to drawings showing only one embodiment. Here are from the drawings and their description further features essential to the invention and advantages of the invention.

Figur 1:

Seitenansicht eines Arbeitsstuhls,

Figur 2:

ein Mittenlängsschnitt durch die Anordnung nach Figur 1 bei mittlerer Einstellung der Rückstellkraft,

Figur 3:

die Draufsicht auf die Anordnung nach Figur 1 und 2,

Figur 4:

eine Darstellung wie Figur 2 in einer zweiten Spannstellung bei leichtester Einstellung der Rückstellkraft,

Figur 5:

eine Darstellung wie Figur 2 in einer dritten Spannstellung bei stärkster Einstellung der Rückstellkraft,

Figur 6:

eine Darstellung wie Figur 2 mit abgesenktem Lehnenbügel und verriegeltem Einstellmechanismus.

Show it:

FIG. 1:

Side view of a work chair,

FIG. 2:

4 shows a central longitudinal section through the arrangement according to FIG. 1 with medium setting of the restoring force, FIG.

FIG. 3:

the top view of the arrangement according to Figures 1 and 2,

FIG. 4:

a view like Figure 2 in a second clamping position with the slightest adjustment of the restoring force,

FIG. 5:

2 shows a representation in a third clamping position with the strongest setting of the restoring force,

FIG. 6:

a representation as Figure 2 with lowered backrest bar and locked adjustment mechanism.

In the figures 1 to 6 a work chair is generally shown, which consists of a lift column 5 which is fixed in the seat support 7. On the seat support 7, a backrest support 1 engages, which is pivotally connected to the seat support 7, each with a right and left tab 2 (see Figure 3). For this purpose, the respective tab 2 is rotatably mounted in a bearing 8 on the seat support 7.

The upper seat bearing 3 is used for pivotally receiving a seat plate, not shown, which attaches via a non-illustrated tab on this seat bearing 3.

The front end of the seat plate, not shown, is pivotally attached via a further tab, not shown, to a front seat bearing 4. The tabs are firmly connected to the seat plate.

It is important that at the front end of the seat support 7, a pivot bearing 24 is present, which receives a link 23, which is thus formed in the arrow directions 37 about this bearing 24 pivotable. As already stated, the front end of the seat plate, not shown, is received in the front seat bearing 4, so that this front end is formed pivotable with the associated link 23.

In a pivoting of the arm 23 about the pivot bearing 24 and thus not shown seat plate is pivoted about the seat bearing 3 around.

According to Figures 1 and 3, the backrest support 1 is connected to a respective tab 2, wherein the tab 2 is received in the bearing 8. This results in a free, pivotable, lower part of the tab 2, in which a bearing 9 is incorporated. This bearing 9 is the pivot bearing for a locking member 10. The locking member 10 consists essentially of two mutually parallel tabs 11, which essentially form a U-shaped part, in the central region of a rack 12 is arranged.

The locking member 10 is thus rotatably connected to the tab 2 and makes because of the movement of the backrest support in the direction of arrow 34 with the same movement, where it pivots about the bearing 8.

It is therefore a bearing 9 is used because on the bearing pin provided in the bearing 9 store other parts, namely in particular the parts for the locking plate 26 and the hand-adjustable locking the pivot adjustment.

In the tab 2, an axis 17 is arranged in the free, pivotable part, in which an actuating lever 16 is pivotally received. This operating lever 16 is fixedly connected to a tab 36, in which a slot 18 is incorporated.

In the slot 18, a guide pin 19 is slidably received, so that so that the compression spring 21 is freely adjustable. It is also mentioned that instead of a helical compression spring, all other known energy stores can be used, such as gas springs, hydraulic springs, elastomer springs and the like.

In the illustrated embodiment, the spring guide of the compression spring 21 consists of a lower spring guide 20, in which the guide pin 19 is arranged and arranged from a displaceable thereto, the upper spring guide 22nd

It is therefore about two telescopically movable sleeves, which form the spring guides 20, 21.

The upper part of the spring guide 22 is pivotally received in the upper seat bearing 4.

The adjustable locking of the lower spring guide 20 now takes place in that when pivoting the lever 16 in the direction of arrow 38, the tab 36 pivots about the pivot point of the axis 17 and hereby the slot is adjusted transversely in the direction of the longitudinal axis of the helical compression spring. Thus, the point of application of the compression spring 21 is changed to the backrest support, because the entire end of the spring guide 20 is now pivoted in the direction of arrows 33.

This pivoting in the direction of arrow 33 is therefore only possible because the backrest support 1 has not yet been pivoted in the direction of arrow 34.

Was the desired point of the compression spring 21 found on the backrest support by adjusting the lever 16, then the backrest support 1 can be pivoted in any position in the direction of arrow 34 to the rear. This pivoting ensures that the locking member with the rack 12 pivots counterclockwise about the bearing 8 and in this case a arranged on the rack 12 locking recess 31 engages with an associated tooth 32 on the lower spring guide 20 of the energy storage locked the backrest, and there is the significant advantage that when pivoting down the backrest carrier of the energy storage with a previously preselected force applied to the backrest support 1 and hereby a desired restoring force for the backrest carrier could be previously set (Figure 6).

It is important that when pivoting the backrest support in its rest position according to Figure 1 and Figure 2, the previously described locking engagement between the locking member 10 and the tooth 32 of the spring guide 20 disengaged comes, so now on the lever 16 another pivot position of the compression spring 21 can be selected in relation to the tab 2.

That is, the tooth 32 can be engaged with relieved backrest support in any locking recess 31 on the locking member 10.

For example, if an upper recess 31 is used for the locking engagement, then the backrest support 1 is biased only with a small biasing force (clamping position of Figure 4), whereas when a lower recess 31 is used at the lower end of the locking member for the locking engagement of the energy storage a high biasing force acts on the backrest support 1 (clamping position of Figure 5). By contrast, FIG. 2 shows a middle clamping position.

It is important that the energy storage itself only needs to be equipped with a relatively small dimensioned compression spring 21, because even an additional bias of the compression spring by Nachobenverschwenken the arm 23 in the direction of arrow 35, when the backrest is pivoted in the direction of arrow 34 to the rear. In this way, the upper spring guide 22 is still pressed against the lower spring guide 20, whereby the compression spring 21 is additionally compressed and thereby the spring force is increased.

For completeness, it should be mentioned that the seat support 7, a rotary button 25 for the height adjustment of the lift column 5 is present.

Furthermore, it is mentioned that a rotary button not shown for a locking of the pivoting movement of the backrest and thus of the backrest support 1 is present. This locking is effected in that a forwardly directed longitudinal lever 28 is connected to the locking part 10, which forms a front guide recess 29 for the longitudinal guide of a locking plate 26 arranged displaceably there.

In the locking plate 26, a series of consecutive holes 27 are arranged, and the locking of the backrest support in any pivot position is possible in that by the locking plate 26, a spring-loaded pressure pin (locking or index pin) can be engaged, thereby forming a connection between the locking part 10 and the associated backrest support 1 in the region of the seat support 7 is made.

Thus, the backrest support 1 is fixedly coupled to the seat support 7 and the backrest support can thus no longer be pivoted in the direction of arrow 34 and in the opposite direction.

The locking plate 26 moves analogously to the pivoting movement of the backrest carrier in the direction of arrows 34 and in the opposite direction thereto, which is represented by the arrow direction 30.

The spring-loaded locking pin (not shown in the drawing) sits on the seat support in the region of the front bore 27. However, if the backrest support 1 is pivoted in a half-pivoted position and then locked, then the bore 27 moves in the locking plate 26 in alignment with the front bore 27th on the seat support, so that now in the middle hole of the locking plate of the locking pin is inserted.

If, on the other hand, the backrest support is locked in a strongly pivoted-down position, then the rearmost hole 27 in the locking plate 26 moves forwards, where in the drawing of FIG. 2 the foremost bore 27 on the seat support is shown and in this comparison of the bore 27 and not closer shown hole in the seat support then engages the spring-loaded pressure pin.

drawing Legend

1

backrest support

2

Flap (right and left)

3

seat support

4

seat support

5

lift column

6

arrow

7

seat support

8th

Bearing on seat support 7 (for part 2 and part 10)

9

Force fit for part 2 and part 10, bearings for part 28

10

locking member

11

flap

12

rack

13

14

15

16

actuating lever

17

Axis (for part 16 and part 36)

18

Long hole

19

guide pin

20

Lead (below)

21

compression spring

22

Lead (above)

23

handlebars

24

pivot bearing

25

Rotary key (height adjustment)

26

locking plate

27

drilling

28

longitudinal lever

29

Guide recess (seat support 7)

30

arrow

31

recess

32

tooth

33

arrow

34

arrow

35

arrow

36

flap

37

arrow

38

arrow

Claims (8)

1. Working chair with an adjustable backrest support biasing force, in which a pivotable backrest support (1) is arranged on a seat support (7) and is biased with a biasing force, which can be adjusted by hand, of an energy store (21) against the back of the user, wherein the front end of the energy store (21) is rotatably mounted on a free, pivotable end of a connecting rod (23) close to the edge of the seat and the rear end of the energy store (21) is articulated to a free, pivotable end of the backrest support (1) and wherein this engagement point is configured to be adjustable and fixable and a locking part (10) is arranged on the backrest support (1) and can be brought into engagement with the energy store (21), characterised in that the locking part (10) is configured as a toothed rack (12) and the latching recesses (31) of the toothed rack (12) are directed toward the energy store (21), which, with an associated spring guide (20, 22) and a tooth (32) arranged on the rear end of the spring guide (20, 22) can be brought into engagement with the latching recesses (31) of the toothed rack (12) of the locking part (10).
2. Working chair according to claim 1, characterised in that the energy store is configured as a helical compression spring (21), the engagement point of which on the pivotable part of the backrest support (1) can be pivoted by hand.
3. Working chair according to claim 2, characterised in that an actuating lever (16), which is accessible from outside, is non-rotatably connected to a bracket (36), in which a slot (18) is arranged, in which the spring guide (20, 22) of the energy store (21) is displaceably guided.
4. Working chair according to any one of claims 1 to 3, characterised in that the locking part (10) is self-locking.
5. Working chair according to any one of claims 1 to 4, characterised in that the front end of the energy store (21) is additionatly biased toward the rear backrest-side end of the energy store.
6. Working chair according to any one of claims 1 to 5, characterised in that there is a prepositioning of the engagement of the energy store (21) with respect to the toothed rack (12) on the locking part (10).
7. Working chair according to claim 6, characterised in that an index pin is present on the free, pivotable end of the energy store (21) and engages in a springloaded manner in an associated indexing rail and thus brings the tooth (32) of the spring guide (20, 22) opposite a latching recess (31) of the toothed rack (12).
8. Working chair according to any one of claims 1 to 7, characterised in that there is a stepless engagement of the backrest-side end of the energy store (21) in the associated locking part (10).

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