Item of seating furniture with a spring-mounted backrest

Abstract

An item of seating furniture (100), with backrest (101), seat surface (102), supporting structure and resetting mechanism (200), wherein the backrest (101) and the seat surface (102) are connected to the supporting structure. The backrest (101) is pivotable relative to the supporting structure about a pivot axis from a first position into a second position, and the backrest (101) is connected to the seat surface (102) via connector (103). The connector (103) is designed such that, when the backrest (101) pivots relative to the seat surface, the seat surface (102) is inclined relative to the supporting structure, wherein the resetting mechanism (200) are designed to exert a resetting force on the backrest (101) in the second position, the resetting force is directed in the direction of the first position, wherein the item of seating furniture (100) with setting mechanism (104) which is designed to set the resetting force.

Claims

1. An item of seating furniture (100), comprising: a backrest (101), a seat surface (102), a supporting structure and a resetting mechanism (200), wherein the backrest (101) and the seat surface (102) are connected to the supporting structure, wherein the backrest (101) is pivotable relative to the supporting structure about a pivot axis from a first position into a second position, wherein the backrest (101) is connected to the seat surface (102) via a connector (103), wherein the connector (103) is designed such that, when the backrest (101) pivots relative to the seat surface, the seat surface (102) is inclined relative to the supporting structure, wherein the resetting mechanism (200) is designed to exert a resetting force on the backrest (101) in the second position, said resetting force being directed in the direction of the first position, wherein the item of seating furniture (100) comprises a setting mechanism (104) which is designed to set the resetting force, wherein the resetting mechanism (200) comprises a spring (200), wherein the spring (200) is designed as a helical spring with a plurality of turns, the number of turns per length unit of the spring (200) is inconstant and/or the turns have different radii of curvature.

2. The item of seating furniture (100) according to claim 1, wherein the resetting mechanism (200) is supported on the seat surface (102) and is connected to the connector (103).

3. The item of seating furniture (100) according to claim 1, wherein the connector (103) comprises a linkage.

4. The item of seating furniture (100) according to claim 1, wherein the resetting mechanism (200) is designed to exert the resetting force on the backrest (101) during the entire pivoting operation of the backrest (101).

5. The item of seating furniture (100) according to claim 1 wherein the spring (200) has a pretension, and wherein the pretension is adjustable.

6. The item of seating furniture (100) according to claim 5, wherein the setting mechanism (104) comprises a threaded rod and a gripping device which is screwable onto the threaded rod, wherein the pretension is settable by the extent to which the gripping device is screwed onto the threaded rod.

7. The item of seating furniture (100) according to claim 6, wherein the threaded rod has a left-handed thread.

8. The item of seating furniture (100) according to claim 6, wherein the threaded rod has a trapezoidal thread.

9. The item of seating furniture (100) according to claim 1, wherein the number of turns of the spring (200) per length unit increases continuously from one end to another end of the spring (200).

10. The item of seating furniture (100) according to claim 1, wherein the radii of curvature increase continuously from one end to the other end of the spring (200).

11. The item of seating furniture (100) according to claim 1, wherein the resetting mechanism (200) is disposed vertically relative to the seat surface (102).

Description

(1) The invention is described in more detail with reference to the attached figures, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

(2) FIGS. 1A-1E show schematic illustrations of an item of seating furniture according to one embodiment of the invention in various positions;

(3) FIGS. 2A-2C show schematic illustrations of the resetting means and setting means in the case of an item of seating furniture according to one embodiment of the invention;

(4) FIG. 3 shows a schematic illustration of the item, of seating furniture from FIG. 2 with differently set resetting means.

DETAILED DESCRIPTION OF THE INVENTION

(5) FIGS. 1A to 1B illustrate an item of seating furniture 100 with a backrest 101 and a seat surface 102. The backrest 101 is connected to the seat surface 102 via a linkage 103. A user can move the backrest 101 rearwards. This operation is illustrated in FIGS. 1A to 1E. In FIG. 1A, the backrest 101 is in a first position. In FIG. 1E, the backrest 101 is in a second position. The movement of the backrest 101 is converted via the linkage 103 into a movement of the seat surface 102. By means of this movement, the seat surface 102 changes its inclination relative to a supporting structure (not illustrated) to which both the backrest 101 and the seat surface 102 are fastened.

(6) A resetting force acts on the backrest 101 in the direction of the first position. Said resetting force can be set by a gripping means 104.

(7) FIGS. 2A to 2C more clearly illustrate how the resetting force is produced and how it can be adjusted. A helical spring 200, which is supported at one end of the seat surface 102, is provided. When the backrest 101 is moved from the first position in the direction of the second position, the spring 200 is compressed. If force is no longer exerted on the backrest 101 by the user, the resetting force of the spring 200 moves the backrest 101 into the first position again.

(8) The pretension of the spring 200 in the first position can be set by the gripping means 104. The gripping means can be screwed onto a threaded rod, as a result of which the spring is likewise compressed. The spring 200 has a progressive force increase. This means that the force which is required in order to deform the spring becomes greater the further the spring is compressed. This can be achieved, for example, by a conical spring shape or by a continuous change in the number of spring coils per length unit. Therefore, the further the gripping means 104 is screwed onto the threaded rod, the greater the force has to be in order to move the backrest 101. The resetting force can thus be set to the requirements of different users.

(9) A comparison in FIGS. 3 and 2B makes it particularly clear how different resetting forces can be set. In the two figures, the backrest 101 is at the same angle with respect to the seat surface 102. However, in FIG. 3, the gripping means 104 is screwed further onto the threaded, red, and therefore the spring 200 is further compressed and a greater force is required for moving the backrest 101.