EP1874160A1

EP1874160A1 - Seating, especially office chair

Info

Publication number: EP1874160A1
Application number: EP06742717A
Authority: EP
Inventors: Hermann Bock
Original assignee: Bock 1 GmbH and Co KG
Current assignee: Bock 1 GmbH and Co KG
Priority date: 2005-04-28
Filing date: 2006-04-27
Publication date: 2008-01-09
Anticipated expiration: 2026-04-27
Also published as: DE102005020247B3; CN101166443A; EP1874160B1; CN101166443B; US20080100119A1; DE202005006980U1; WO2006114311A1; JP2008538950A

Abstract

The invention relates to a seating, especially an office chair. The aim of the invention is to provide, with relatively few constructive elements, an office chair that offers the comfort comparable to that obtainable by a synchronous mechanism. For this purpose, the seating comprises a seating element (1) having a seat (9), and a back element (2) articulated to the seat (1) and pivotable about a transversal axis (6). The seat (9) of the seating element (1) is configured in such a manner that, when the back element (2) is pivoted into a rearward position, the user is brought in a position simulating the movement of the back element (2), thereby allowing a movement of the body of the user in synchronicity with the movement of the back element, without the entire seating element carrying out such a synchronous movement.

Description

Seating furniture, in particular office chair

The invention relates to seating, in particular an office chair.

So-called synchronous mechanisms are known from the prior art. These are assemblies in the seat base of an office chair that enable a correlated movement of the seat backrest. The seat support and backrest support are articulated in such a way that a pivoting movement of the backrest to the rear, as can be caused, for example, by the chair user leaning against the backrest, induces a lowering movement of the rear edge of the seat downward. This brings a considerable comfort advantage and is desirable for orthopedic reasons. A disadvantage of these synchronous mechanisms is their comparatively complicated mechanical structure. As a result, synchronous mechanisms are also comparatively expensive to manufacture.

An object of the present invention is to provide a solution which, with a comparatively low design effort, provides a comfort advantage which is comparable to that of a synchronous mechanism.

This object is achieved by a piece of seating furniture according to claim 1. Thereafter, a piece of seating furniture is provided which consists of only two main assemblies, namely a preferably fixed seat element and a back element, the seat element having a seat surface and the back element being pivotable and articulated about a transverse axis the seat element is connected. According to the invention, the seat surface is designed such that when the backrest is pivoted backwards, as is caused, for example, by the user leaning against the back element, the movement of the

Back element tracing movement performed. In other words, the design of the seat surface results in a lowering movement of the user when the backrest is pivoted backwards, without the seat element itself moving. This enables a synchronous movement of the user's body to the movement of the back element without the entire seat element performing such a synchronous movement. This leads both to a shift in the center of gravity of the user and to a shift in movement in the sense that the user carries out a movement with the aid of the invention that largely corresponds to the movement that a user would carry out using a corresponding synchronous mechanism. With the help of the invention, a comfort advantage which is comparable to that of a much more expensive synchronous mechanism is achieved in a structurally simple and therefore also very inexpensive manner. In particular, the so-called "shirt pull-out effect" is effectively avoided.

Advantageous refinements are specified in the subclaims.

According to a particularly advantageous embodiment of the invention, the seat surface has at least two in

Longitudinal direction of seat areas arranged one behind the other, which differ in the way they are upholstered. The term padding is used here understood any elastic configuration of the seat, no matter what material is used for it. In addition to the use of molded foams, any other elastic materials can in principle also be used, for example spring assemblies or combinations of materials such as foam in conjunction with silicone cushions. The use of two-zone foam is also possible, for example.

It is very particularly advantageous if at least one rear seating area has upholstery which enables the user to sink in more than a front seating area. If the user moves backwards and the seat is stressed in the rear area, this occurs simultaneously

In other words, the rear seating area is designed in such a way that when the backrest is loaded, the pelvis of the user slides into the upholstery in the manner of rolling. This results in a particularly synchronous movement between

Back element and user achieved.

It is also particularly advantageous if the back element is connected to the seat element via a pivot axis which is arranged in the longitudinal direction of the chair before the chair column is attached to the seat element. The position of the pivot axis contributes significantly to the fact that an ergonomically very advantageous sitting is possible.

If spring elements are provided for pretensioning the back element, which are arranged essentially horizontally in the seat element, a particularly flat design can be achieved. As spring elements are depending on the construction any springs, such as tension or compression springs, can be used.

Further advantageous refinements of the invention are described using an exemplary embodiment which is explained in more detail with the aid of the drawings. Here show:

Fig. 1 is a perspective view of the seat element without a seat (first spring position), Fig. 2 is a section through the seat element (first

3 a section through the seat element (second

Spring position),

4 shows a further section through the seat element (first spring position) with seat cover,

Fig. 5 shows a further section through the seat element

(second spring position).

The office chair according to the invention comprises a seat element 1 and a back element 2. As shown in FIG. 2, the essentially horizontally arranged seat element 1 is pivotally connected to the back element 2 at a bearing point 3. In other words, the back element 2 is articulated and carried out in the area of the underside 4 of the seat element 1, for example when the user is leaning against the back element 2, a pivoting movement 5 about the pivot axis 6 which runs through the pivot bearing and which runs transversely to the longitudinal direction 7 of the chair .

The type of back element 2 is irrelevant to the invention. For example, the back element 2 can comprise a backrest in the form of a shell, a net or the like. The back element 2 can be transferred from its normal position shown in the figures into a rear position and back. To change the restoring force of the back element 2, a spring force setting 8 is provided, the exact functioning of which will be explained later.

The seat element 1 comprises on the one hand the actual seat support with the articulation of the back element 2 and the spring force setting 8. Because the fulcrum of the mechanism is arranged very close under the seat surface 9, the sequence of movements when the back element 2 is moved backwards is similar to that of one Synchronous mechanism. In particular, the so-called shirt pull-out effect is reduced. In other words, the horizontal and vertical position of the pivot axis 6 relative to the seat element 1 or to the back element 2 is particularly crucial for the movement sequence that can be achieved.

In addition, all other mechanical components are also integrated in the seat element 1, for example the receptacles 10 for armrests (not shown). In other words, the functional components of the seat support and mechanics form a structural unit. The integrated and compact design of the seat element 1 is particularly clear from FIG. 1. The cost-effective production is particularly advantageous in this type. In addition, the number of individual parts required is significantly reduced, which also reduces manufacturing costs and also increases reliability. A cone receptacle 11 is provided approximately in the center of the seat element 1 and serves to receive the upper end of a chair column, for example a gas spring (not shown).

The base body 12 of the seat element 1 essentially consists of a plastic plate with a number of wall elements 14 extending in the longitudinal direction 7 of the chair and the transverse direction 13 of the chair. These serve not only to achieve the required stability of the seat element 1. At the same time, a significant material saving is possible. In addition, the wall elements 14 also partially perform other tasks. For example, they serve as a guide or holding element for the trigger rod 15 for height adjustment of the gas spring, the trigger rod 15 being actuated via a button 16 which is also integrated in the base body 12. The wall elements 14 also serve to hold and guide the drive shaft 17 of the spring force setting 8, an actuating element (not shown in FIG. 1), for example in the form of a handwheel, being attached to the free end 18 of the drive shaft 17.

A spring arrangement is used to return the back element 2 from its rear position to its normal position. The spring arrangement comprises two compression springs 19 with a circular cross-section, which lie in corresponding spring receptacles 20 provided in the base body 12.

Apart from the fact that the spring angle by the displacement of the spring linkage when the

Spring force setting 8 can be changed, the compression springs 19 lie essentially horizontally in the seat element 1, which results in an extremely flat design leaves. On the one hand, the low overall height enables a visually appealing design of the chair. In addition, the use of a wide variety of chair columns or gas springs is possible, so that special requirements for seat heights can also be met.

The position of the two compression springs 19 is changed via a U-shaped round steel 21, the U-legs 22 of which are inserted into the two round springs 19. The compression springs 19 are raised or lowered on one side via the movement of the “U-base” 23 of the round steel 21 in the deflection direction 24, while the opposite ends of the compression springs 19 remain in their starting position by fixing the ends 25 of the round steel 21 on the base body 12 the rounded ends 25 lie in a kind of ball socket 26 on the base body 12.

When the back element 2 is loaded, that is to say when the back element 2 moves into a rear position, pivot pins 28 attached to the shaft 27 and extending from the underside 4 through the base body 12 to the round steel bar 21 press against the compression springs 19 and thus provide an operative connection between the compression springs 19 and the back element 2 ago. The pivot lugs 28 are U-shaped as a guide such that they receive the U-legs 22 of the round steel 21.

When the spring force adjustment is changed, the rotation of the drive shaft 17 causes a worm wheel 29 attached to it to rotate, which results in a rotation of a toothed wheel 30 engaging therein. The gearwheel 30 is arranged on a thread axis 31 running in the deflection direction 24, that is to say perpendicularly, on which a thread is used Boom 32 is attached. The arm 32 has a U-shaped driver 33 which carries the round steel 21 up or down, depending on the direction in which the drive shaft 17 is rotated. As a result, the position of the compression springs 19 from a lower first spring position

(Fig. 1, 2, 4) in an upper second spring position (Fig. 3, 5) changed. In other words, a "powerless" spring force setting is possible. Only the position of the compression springs 19 and thus the articulation angle changes. In other words, the spring force setting takes place under

Inclusion of the laws of the lever law in that the compression springs 19 attack at different points on the articulation lugs 28. By moving the articulation points in the direction of deflection 24, the lever arm is lengthened or shortened, so that the round springs 19 are more or less compressed.

The upholstery 34 of the seat 9, cf. Fig. 4, consists of molded foam and is attached to a seat plate 39 which can be mounted on corresponding receptacles 40 of the base body 12. Due to the special design of the padding 34, the user rolls backwards as it were when the back element 2 is moved. It slides into the foam. The foam must therefore be free in the direction of the seat end 35 in order to be able to expand to the rear. In order to achieve this, an open design of the upholstery 34, without rearward limiting elements, is preferred.

The seat surface 9 is divided into two different seat areas 36, 37 arranged one behind the other in the longitudinal direction 7 of the seat, which differ in the way they are upholstered. The shape of the seat 9 used in the present example is the front one Seat area 36, which accounts for approximately 30% to 40% of the total length of the upholstery 34, is provided with a “normal” upholstery thickness, while the rear seat area 37 (between 70% and 60% of the total length) is provided with a variable upholstery 34 which In the example shown, the upholstery thickness of the rear seat area 37 is increased by at least 20 mm compared to the upholstery thickness of the front seat area 36. The manner of transition from the front seat area 36 to the rear seat area 37 is preferably very soft and flowing and without edges. Particularly good results have been achieved with a transition area 38 in the form of an elongated lying S. The transition from the front seating area 36 to the rear seating area 37 is positioned in such a way that in a normal (" average ") posture essentially strains the front seating area. If the backrest is then loaded, the user's pelvis rolls over the lying S into the rear seating area. The user thus follows the movement of the

Backrest down back.

Reference symbol list

1 seat element

2 back element

3 bearing point

4 underside of seat element

5 swivel movement 6 swivel axis

7 longitudinal direction of the chair

8 spring force adjustment

9 seat 10 armrest mount

11 cone holder

12 basic bodies

13 chair cross direction 14 wall element

15 release rod

16 release button

17 drive axle

18 drive axle free ends 19 compression spring

20 spring mount

21 round bars

22 U-legs

23 U-Grund 24 direction of deflection

25 round steel end

26 ball socket

27 wave

28 Articulation nose 29 Worm wheel

30 gear

31 thread axis

32 outriggers

33 carrier 34 padding

35 seat end

36 Front seating area

37 Rear seating area

38 transition area 39 seat plate

40 recording

Claims

Expectations

1. Seating furniture, in particular office chair, with a seat element (1) which has a seat surface (9), and with a back element (2) which can be pivoted about a transverse axis (6) and is articulated to the seat element (1), the seat surface ( 9) of the seat element (1) is designed in such a way that when the back element (2) is pivoted into a rear position, a user executes a movement which is traceable to the movement of the back element (2).

2. Seating furniture according to claim 1, wherein the seat surface (9) has at least two seat areas (36, 37) arranged one behind the other in the longitudinal direction (7) of the seat, which differ in the way they are upholstered (34).

3. Seating furniture according to claim 2, wherein at least one rear seating area (37) has an upholstery (34) that enables the user to roll backwards and downwards.

4. Seating furniture according to one of claims 1 to 3, wherein the transverse axis (6) in the longitudinal direction of the chair (7) before attachment

(11) the chair column is arranged.

5. Seating furniture according to one of claims 1 to 4, with im

Spring elements (19) arranged essentially horizontally in the seat element (1) for prestressing the back element (2).