EP3217845B1 - Tilting mechanism and chair with a tilting mechanism - Google Patents

Description

The invention relates to a rocking mechanism for a chair, in particular an office chair according to the preamble of claim 1. Furthermore, the invention relates to a chair, in particular an office chair with such a tilt mechanism.

The invention relates to a tilt mechanism for chairs, as they are used in particular as office chairs. Such an office chair typically has a foot portion with which the chair stands up on the floor. The foot can, for example, be equipped with fixed foot elements or with rollers for moving the foot part on a substrate.

There is a centrally arranged vertical element which connects a seat surface with the foot part. The seat is arranged substantially horizontally so that a person can sit on this seat. Optionally, the chair still on a backrest and / or one or two-sided arranged armrests. In general, the seat is arranged rotatably relative to the foot part about a vertical axis of rotation.

The central support element can be designed to be height adjustable. For this purpose, an adjustable gas spring is often used. This serves on the one hand for height adjustment and on the other hand, at least partially for damping or suspension in the vertical direction, for example, when a person sits down on the seat.

In order not to excessively burden or even relieve the musculoskeletal system and in particular the back of the person, the seat can be equipped with a tilt mechanism, which arranges the seat movable relative to the foot part. As a result, the seat can be inclined relative to the foot part, preferably by a few degrees. Corresponding office chairs are known in which such a one-dimensional inclination of the seat in the direction of the user, so viewed from this forward or backward is possible. This usually serves a corresponding pivot axis. Optionally, an additional Inclination to the sides are made possible by a second pivot axis. In this case, this is called a 3D rocker.

Both an inclination to the two sides and to the front and back, so perpendicular to this requires a so-called neutral position. The seat is in the unloaded or centrally loaded state in this typically central neutral position. Incidentally, a person located on the seat by tilting the weight of the seat side or tilt forward or backward, preferably starting from the neutral position.

With a central bearing by two relatively mutually movably arranged bearing parts, the inclination is made possible, for example by means of two physical perpendicular to each other pivot axes. The upper bearing part serves for connection to a seat surface for a person and the lower bearing part for connection to the foot part for setting up the chair on a substrate.

The bearing parts are tilted relative to each other in a predetermined angular range by shifting the weight of the person. The known rocking mechanisms are equipped with metal springs for adjusting the neutral position. This leads to a comparatively static and, especially with prolonged use to usually stiff and noisy movements of the spring elements.

The DE 20 2009 011 789 U1 discloses a seat support for seating and standing aids, in which a Kugelflanschlager is provided between a seat receiving plate and a center mandrel, wherein the ball of the Kugelflanschlagers is movably mounted between a circumferential in a horizontal plane bearing shell of the housing. In addition, several buffers are provided circumferentially for damping tilting movements of the seat receiving plate.

The DE 10 2010 047 323 A1 discloses a seat support for an office chair, in which a bearing block is arranged between a chair pillar receptacle and a seat receptacle, in which a pendulum bearing is provided with an inner ring and an outer ring.

The DE 20 2006 019 708 U1 shows a tilt mechanism for a seat, which has two nested ball bearing shells, of which the lower shell is connected to the foot part of the chair and the upper bearing shell with the seat.

The object underlying the invention is to provide a Wippmechanik that eliminates the disadvantages of the prior art. In particular, the new rocker mechanism should enable a noise-free and smooth operation even with long service life.

A Wippmechanik with the features of claim 1 solves this problem. Accordingly, the bearing parts have mutually correspondingly curved bearing shells for mutual storage. This means that both the upper bearing part and the lower bearing part each have a corresponding bearing shell. These bearings are curved in correspondence with each other, i. essentially, they have an identical curvature. In particular, the bearing shells are formed identically at least with respect to the curvature. This allows a smooth and quiet adjustment or inclination of the seat against the foot. Physical pivot axes are preferably not provided. The bearing shells of the two bearing parts are arranged one above the other in the assembled state of the rocking mechanism on a chair. In addition, a plurality of spring elements are provided between the lower bearing part and the upper bearing part, which counteract a deflection and / or are arranged in pairs opposite the center of the bearing shells.

Preferably, the Wippmechanik is characterized in that the bearing shells are spherical shell-shaped relationship meadow formed as spherical shells sections. A spherical shell is a section of a spherical surface. A spherical shell section or a spherical shell therefore does not designate a complete sphere, but only a part of it. Typically, such a spherical shell section is significantly smaller than a hemisphere here. Since a sphere has an identical curvature at all points of the spherical shell, bearing shells with the same curvature or with the same ball diameter can abut one another over the entire surface. Thus, an optimal storage is achieved.

Preferably, the bearing shells are annular or ring-shaped. Accordingly, they preferably have an annular cross-section. Thus, the bearing shell comprises a circumferential, closed edge on the one hand and a free, central region on the other. If the bearing shells are spherical shell sections or similarly curved surfaces, the circumferential annular section is correspondingly curved.

The bearing shells are preferably arranged displaceable relative to one another. Thus, a relative inclination of the bearing parts to each other is made possible. This is achieved in that one of the bearing shells is displaced with respect to the other bearing shell along the curved surface of the bearing shell, ie along a curved path. Alternatively, this movement can be described by a pivot about an axis of rotation, which is arranged at the center of curvature. In isotropic or symmetrically curved bearing shells, the movement therefore runs in all directions along identically curved paths. In the case of anisotropically or asymmetrically curved bearing shells, a plurality of virtual pivoting or pivoting axes may need to be considered.

The relative pivoting or tilting of the bearing parts to each other along the surface of the bearing shells by relative displacement of the bearing shells achieved. This ensures that the inclination of the bearing parts to each other in virtually any direction is changed. A three-dimensional mobility of the bearing parts to each other is thus given within the given degrees of freedom.

According to the invention a plurality of spring elements are provided. These serve to mediate a spring action and / or damping against a relative inclination of the bearing parts to each other. In particular, the spring elements serve to generate an opposing spring action in deflections from the neutral position or inclinations of the bearing parts. This spring effect should preferably serve to return the bearing parts back to the neutral position. In particular, pairs of opposing spring elements are provided, in particular with respect to the center of the bearing and the bearing shells or the vertical axis. More preferably, an even number of spring elements is provided, preferably four or eight spring elements. More preferably, the spring elements are arranged in pairs as opponents. This means in particular that when rebounding one of the spring elements whose opponent springs in and vice versa. Thus, a bilateral suspension can be ensured. The opponents are preferably arranged opposite each other.

In particular, at least a part of the spring elements, preferably all spring elements have an identical spring action and / or damping. Alternatively, individual spring elements or even all spring elements may have different spring action and / or damping. This means that in particular for individual directions of movement, a different strength spring action and / or damping can be adjusted. This can preferably be ensured both by insertion and subsequently by replacing individual or even all spring elements. This can be provided in each direction of movement a certain, possibly different spring action and / or damping.

The spring elements are in particular formed as a hollow body. Preferably, they have a deformable wall. Thus, an elastic effect of the spring elements is achieved. Particularly preferably, the spring elements are cylindrical, more preferably as a hollow cylinder.

According to the invention, the spring elements are formed as elastomer springs or elastomeric spring elements. Elastomeric springs are characterized by permanent elasticity of linear spring action and low manufacturing costs. Moreover, elastomer springs avoid in particular the usual noise development of metallic spring elements.

In particular, the bearing portion of the lower bearing part is provided with a central receptacle, preferably in the manner of a projection. This receptacle is preferably used for fastening a vertical element or a corresponding connecting element arranged on the foot part. As a vertical element or part thereof may preferably serve a gas spring. By the central receptacle has a round cross-section, a rotation of the seat against the foot part about a vertical axis of rotation can already be ensured.

The bearing section of the upper bearing part has in particular a central opening for receiving the central vertical element of the foot part or the central receptacle and / or the associated projection of the lower bearing part. The vertical element may in particular include a gas spring. The breakthrough is required to attach the upper bearing part to the lower bearing part, if a central bearing of the seat is to be provided, such as by means of a gas spring. Namely, the upper bearing part preferably surrounds the lower bearing part at least in part.

The bearing portion of the upper bearing part is supported by means of a pressure washer on the lower bearing part. For this purpose, the pressure disk is preferably annular. In particular, the thrust washer is annular to be disposed about the central receptacle on the lower bearing member. Preferably, for this purpose, a circumferential groove or the like is provided, in which the thrust washer is inserted.

More preferably, at least one sliding element is arranged between the bearing shells and / or between the bearing shell of the upper bearing section and the thrust washer. Such a sliding element may, for example, be a foil, a pane or the like, which is produced in particular from a low-friction material. For example, it may be a Teflon element or the like. Thus, the friction between the bearing shells or between the bearing shell and the pressure plate is reduced, so as to provide a smooth rocker mechanism.

More preferably, an actuating device for a height adjustment of the chair is provided. To adjust the height, in particular, a gas spring arranged in the region of the foot part or of the central vertical element is used. Such a gas spring can be used on the one hand for height adjustment and on the other hand for partial damping. The actuator is preferably designed lever-shaped and / or annular. Preferably, an actuating arm is used to actuate a release button of the gas spring. In particular, a handling handle region is provided at the other end region of the actuating device. The actuating device is preferably triggered by a vertical movement upwards or downwards. In particular, a corresponding axis of rotation can be provided for the actuating device.

The object mentioned above is also achieved by a chair, in particular an office chair or swivel chair with the features of claim 13. This chair preferably has a seat for a person and a foot part for Set up on a surface. The seat is movably connected to the foot part in a limited angular range relative to one another. The chair is characterized in that a rocking mechanism according to the above description is provided for the movable connection of the seat surface to the foot part. Accordingly, the above descriptions of the rocking mechanism are applicable in combination with the described chair.

Fig. 1

einen Stuhl beziehungsweise Bürostuhl mit einer erfindungsgemäßen Wippmechanik,

Fig. 2

die Wippmechanik in einer perspektivischen Ansicht von unten,

Fig. 3

die Wippmechanik in einer perspektivischen Ansicht von oben,

Fig. 4

die Wippmechanik in einer Draufsicht von unten,

Fig. 5

die Wippmechanik in einer seitlichen Schnittansicht, und

Fig. 6

die Wippmechanik in einer Explosionsdarstellung.

A preferred embodiment of the invention will be described below with reference to the drawings. In these show:

Fig. 1

a chair or office chair with a rocking mechanism according to the invention,

Fig. 2

the rocking mechanism in a perspective view from below,

Fig. 3

the rocking mechanism in a perspective view from above,

Fig. 4

the rocking mechanism in a plan view from below,

Fig. 5

the Wippmechanik in a side sectional view, and

Fig. 6

the rocking mechanism in an exploded view.

The chair 10 as an office or swivel chair is characterized by a rocking mechanism 11 according to the invention.

This rocking mechanism 11 is arranged below a seat surface 12 for connection to a foot part 13 of the chair 10. Between the rocking mechanism 11 and the actual foot part 13, however, a vertical element 14 is still arranged. The vertical element 14 has a gas spring 15 in the interior.

For actuation or height adjustment of the gas spring 15, an actuating lever 16 is provided below the seat surface 12 in the region of the tilt mechanism 11. This operating lever 16 is used to actuate an upper-side control knob 17 of the gas spring 15. In an upward movement of the operating lever 16 on the outside End portion by engagement of a user is due to the lever axis 18 of the gas spring-side end portion 19 of the operating lever 16 is moved downward, so that the control knob 17 is depressed. This leads to a release of the gas spring 15, which can freely expand at low weight load on the chair 10. In a typical load with a person, however, the gas spring 15 is compressed, so that the rocking mechanism 11 moves downwards with the seat surface 12.

As an alternative to the actuating lever 16 shown here, in particular also an actuating ring (not shown here) can be provided. Instead of a single lateral actuating lever 16 then a circumferential ring is disposed below the seat surface 12. This ring can also be actuated by an upward or downward movement of the corresponding control knob 17 of the gas spring 15.

Incidentally, the chair 10 here also has a backrest 19, which is fastened to the seat surface 12. In the illustrated embodiment, however, no further elements, such as armrests or the like are provided. These can however be added if necessary.

Both the seat 12 and the backrest 19 each have a padding 20. This serves to increase the convenience for a user of the chair 10, so a person sitting on it.

The foot part 13 has in the illustrated embodiment 5 of a central region projecting arms 21. These arms 21 serve to achieve a secure state of the chair 10 on a substrate.

As in the embodiment shown, at the end regions of each of the arms 21 rotatable rollers 20 about vertical axes can be arranged, with the seat surface 12 screwed on the underside. The lower bearing part 24, however, is placed on the upper portion of the vertical life 14 in the form of the housing of the gas spring 15. The gas spring 15 or the vertical element 14 has at the upper portion corresponding to an outer shape, which corresponds to the interior of an associated receptacle 26 of the lower bearing part 24. Typically, this is a round cross-section. Basically, but also other cross sections be conceivable. A round cross section offers the advantage that the seat surface 12 can already be rotatable relative to the vertical element 14 thereby.

The upper bearing part 23 is formed as a housing 27, that the lower bearing part 24 receives inside it. Accordingly, the upper bearing part 23 substantially encloses the lower bearing part 24.

The actual storage of the two bearing parts 23, 24 to each other is completed by two so-called cups 28 and 29. The first bearing shell 28 is formed on the housing 27 of the upper bearing part 23 at. In principle, however, this bearing shell 28 can also be designed as a separate part that is connected in a different way to the upper bearing part 23. In any case, the bearing shell 28 is formed as a spherical shell-shaped element. This means that the bearing shell 28 has a shape or curvature which corresponds to a section of a spherical surface.

The lower bearing part 24 also has an integrally formed bearing shell 29. The bearing shell 28 is formed as part of the lower bearing part 24. Specifically, here the lower wall is formed as a bearing shell 29. However, a second bearing shell 32 is still provided, which actually serves as a support for the upper bearing part 24. Therefore, the bearing shell 29 could indeed be omitted in principle. But it serves as an investment and to secure storage upwards.

The shape and curvature of the bearing shells 29 and 32 essentially correspond to those of the bearing shell 28. In other words, the radii of curvature of the respectively associated spherical surfaces also correspond. It is ensured that the two bearing notes 28 and 29 always create an optimal manner to each other within the intended movement-dependent inclination range. An optimal power transmission is guaranteed.

Since the upper bearing part 23 practically completely surrounds the lower bearing part 24, the bearing shell 28 is arranged below the bearing shell 29. To allow the two bearing notes 28 and 29 as fully as possible abut against each other and to provide support for the upper bearing part 23 on the lower bearing part 24 via the bearing shell 32, therefore, a thrust washer 30 is provided. This pressure plate 30 is on the projection 31 of the lower bearing part 24 is placed and secured thereto. For this purpose, a circumferential groove 36, in which the pressure plate 30 is inserted.

Between the thrust washer 30 and the bearing shell 28, a bearing shell 32 is additionally provided as a lower bearing element. Accordingly, the bearing shell 28 rests on the lower bearing shell 32, which has fallen over the thrust washer 30 on the projection 31. At the top, the bearing shell 28 is formed adjacent to the upper bearing shell 29. This upper bearing shell 29 is part of the lower bearing part 24 and does not have to be explicitly designed as a bearing shell.

In order to allow passage of the projection 31 through the bearing certificate 28, this has a central opening 33. This opening 33 is usually formed as a circular opening. In order to allow a relative mobility of the two bearing parts 23 and 24 against each other and ultimately an inclination of the seat surface 12, the opening 33 has a larger cross section than the projection 31. Accordingly, gaps 34 are laterally in the area between the bearing shells 28, 29 and 32 and the projection 31 is present. These gaps 34 allow a lateral pivoting movement by displacement of the upper bearing part 23 relative to the lower bearing part 24. The pivoting movement is limited by a stop of the bearing shell 28 laterally to the projection 31 on one side. Since the area around the projection 31 including the bearing shells 28, 29 and 32 is circular and thus point-symmetrical to the center, an inclination in each spatial direction is possible.

The detailed in the Fig. 5 shown relative orientation of the two bearing parts 23 and 24 to each other corresponds to the so-called neutral position. This is the orientation in unloaded condition. Starting from this neutral position, pivoting can take place by displacing the bearing parts 23 and 24 relative to each other on both sides. This is made possible because corresponding gaps 34 are present around the projection 31.

Between lower bearing part 24 and upper bearing part 23 also spring elements 35 are still provided, which are formed in the embodiment shown as elastomer springs or elastomeric spring elements. On the one hand, the elastomer springs or spring elements 35 serve to hold the two bearing parts 23 and 24 in the mentioned, in particular central, neutral position. For this purpose, the spring elements 35 under bias between the upper bearing part 23, the lower bearing part 24 is inserted. This ensures that in symmetrical construction of the spring elements 35, a substantially central neutral position is taken. Accordingly, the circumferential gap 34 is formed with a constant cross section.

In the embodiment shown, a total of eight spring elements 35 are provided. The spring elements 35 are arranged distributed around the circumference of a circular inner region of the tilt mechanism 11. This ensures that each tilting movement of the rocking mechanism 11 is distributed to one or more of the spring elements 35. To the extent that one of the spring elements 35 is loaded, a correspondingly opposite spring element 35 is relieved. According to the setting of the bias of the spring elements 35 already the strength of the spring action can be adjusted.

Incidentally, the spring effect is adjusted primarily by the choice of material and the shape of the spring elements 35. For example, anywhere on the one hand identical spring elements 35 may be used all around. Alternatively, individual directions can be reinforced or weakened by more or less elastic spring elements 35 in the spring action. While identical spring elements 35 should be used on the sides, as a rule, a different thickness of the spring elements 35 can be provided forwards and backwards due to the different desired spring effect. Thus, an individual adjustment of the spring action in different directions of inclination is possible.

When using so-called elastomer springs as spring elements 35 will be formed as a rule, as a cylindrical hollow body. Accordingly, they have a circumferential wall, which can be deformed when force in the vertical direction. The wall will accordingly be deformed into a less bulbous shape, depending on the applied force. Upon discharge of one of the spring elements 35, the stored energy is then released elastically again. This leads to a return movement of the two bearing parts 23 and 24 in the direction of their neutral position.

Alternatively, if appropriate, other types of spring elements 35 may be provided. According to the invention, however, are elastomeric springs over, for example metallic springs to be preferred, since accordingly avoided by these caused noises and other difficulties.

LIST OF REFERENCE NUMBERS

10

chair

11

tilt mechanism

12

seat

13

footboard

14

vertical element

15

gas spring

16

actuating lever

17

control knob

18

lever axis

19

backrest

20

upholstery

21

poor

22

role

23

upper bearing part

24

lower bearing part

25

screw holes

26

admission

27

casing

28

bearing shell

29

bearing shell

30

thrust washer

31

head Start

32

bearing shell

33

breakthrough

34

gap

35

spring element

36

groove

Claims (13)

1. A tilting mechanism for a chair (10), in particular an office chair, having two bearing parts (23, 24) of a central bearing arranged so as to be movable relative to one another, wherein the upper bearing part (23) is formed for connecting to a seat (12) for a person and the lower bearing part (24) is formed for connecting to a base part (13) for placing said chair (10) on a ground, wherein said bearing parts (23, 24) are tiltable relative to each other in a predetermined angular range by shifting the weight of the person and comprise mutually correspondingly curved bearing shells (28, 29, 32) for mutual bearing, and a plurality of spring elements (35) is provided between said lower bearing part (24) and said upper bearing part (23) which counteract a deflection and/or are arranged in pairs opposite the center of said bearing shells (28, 29, 32),
   characterized in that
   said bearing shells (28, 29, 32) of said two bearing parts (23, 24) are positioned one above the other when the tilting mechanism (11) is mounted on a chair (10), wherein said spring elements (35) are designed as elastomeric springs or elastomeric spring elements.
2. The tilting mechanism according to claim 1, characterized in that said bearing shells (28, 29, 32) are formed as spherical shell sections.
3. The tilting mechanism according to claim 1 or 2, characterized in that said bearing shells (28, 29, 32) have an annular cross-section.
4. The tilting mechanism according to any one of preceding claims, characterized in that said bearing shells (28, 29, 32) are arranged so as to be displaceable relative to each other for relative inclination of said bearing parts (23, 24).
5. The tilting mechanism according to any one of preceding claims, characterized in that the relative orientation or inclination of said bearing parts (23, 24) to each other is variable in any direction along the surface profile of said bearing shells (28, 29, 32) by relative displacement of said bearing parts (23, 24) to each other.
6. The tilting mechanism according to any one of preceding claims, characterized in that at least a part of said spring elements (35) has an identical spring effect and/or damping, wherein individual spring elements (35) may have a different spring effect and/or damping.
7. The tilting mechanism according to any one of preceding claims, characterized in that said spring elements (35) are formed as a hollow body having a deformable wall and/or that said spring elements (35) are formed cylindrically.
8. The tilting mechanism according to any one of preceding claims, characterized in that said lower bearing part (24) has a central receptacle (26) for a vertical element (14) of said base part (13).
9. The tilting mechanism according to any one of preceding claims, characterized in that said bearing shell (28) of said upper bearing part (23) has a central opening (33) for receiving the central vertical element (14) of said base part (13).
10. The tilting mechanism according to any one of preceding claims, characterized in that said bearing shell (29, 32) of said upper bearing part (23) is supported on a preferably annular thrust washer (30) on said lower bearing part (24).
11. The tilting mechanism according to any one of preceding claims, characterized in that at least one sliding element is arranged between said bearing shells (28, 29, 32) and/or between bearing shell (28, 29, 32) and thrust washer (30).
12. The tilting mechanism according to any one of preceding claims, characterized in that an actuating device or an actuating lever (16) for a height adjustment of said chair or said seat (12) is provided, wherein said actuating device is preferably formed lever-shaped or annular and/or wherein said actuating device can be triggered by a vertical movement.
13. A chair, in particular an office chair, having a seat (12) for a person and a base part (13) for placement on a ground, wherein said seat (12) is connected to said base part (13) so as to be movable in a limited angular range relative to each other, characterized in that a tilting mechanism (11) according to any one of preceding claims is provided for the movable connection of said seat (12) to said base part (13).

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