Chair, in particular office chair

Abstract

A chair, in particular an office chair, has a backrest which is coupled to a seat support by way of a backrest support. The chair further has a seat face. For tool-free chair assembly the backrest support is constructed in two pieces having a first support member which is associated with the seat support and having a second support member which is associated with the backrest and which is joined to the seat-support-side first support member in a positive-locking plug type connection and is locked therein.

Claims

1. A chair, comprising: a backrest; a seat support; a seat with a seat surface; and a backrest support connecting said backrest to said seat support, said backrest support being constructed in two pieces including a seat-support-side, first support member associated with said seat support and a backrest-side, second support member associated with said backrest; said first and second support members being joined to one another in a positive-locking plug connection and locked therein; one of said first and second support members being formed, at a joint side thereof, with a plug type receiving member and the other of said first and second support members being formed, at a joint side thereof, with an insertion shaft; a locking bar disposed inside said plug type receiving member, said locking bar being rotatably movable.

2. The chair according to claim 1, wherein said locking bar is pivotally mounted in an insertion direction.

3. The chair according to claim 1, which comprises a resilient element disposed inside said plug type receiving member, said resilient element being supported on an inner wall of said plug type receiving member and on said locking bar, and wherein said locking bar pivots counter to a restoring force of said resilient element during a closure of the plug type connection.

4. The chair according to claim 1, wherein said plug connection has an inner side with a recessed stepped contour into which said locking bar pivots during the plug type connection.

5. The chair according to claim 1, wherein said insertion shaft has a convex outer contour at a free end side thereof.

6. The chair according to claim 1, wherein said insertion shaft has a locking contour in which said locking bar pivots out during the plug type connection.

7. The chair according to claim 5, wherein a locking ramp is formed along said locking contour and said locking bar is disposed to slide along said locking ramp during the plug type connection with said free-end-side end face thereof sliding into said locking end position.

8. The chair according to claim 6, wherein an abutment ramp is formed along said locking contour, said abutment ramp running obliquely into a ramp base, and said locking bar pivots out against said ramp base during the locking operation.

9. The chair according to claim 6, wherein said locking contour is formed such that said locking bar, during a pivot movement thereof into the locking end position, draws said insertion shaft into said plug type receiving member in an insertion direction.

10. The chair according to claim 6, wherein said locking ramp is formed to conform to a pivot radius of said locking bar as a ramp depth increases.

11. The chair according to claim 1 being an office chair.

12. The chair according to claim 1, wherein said backrest is pivotally coupled to said seat support.

13. The chair according to claim 1, wherein said seat is coupled to said seat support for movement synchronously with said backrest.

14. A chair, comprising: a backrest; a seat support; a seat with a seat surface; an armrest; and said armrest support being constructed in two pieces including a seat-support-side, first support member associated with said seat support and a backrest-side, second support member associated with said backrest; said first and second support members being joined to one another in a positive-locking plug connection and locked therein; one of said first and second support members being formed, at a joint side thereof, with a plug type receiving member and the other of said first and second support members being formed, at a joint side thereof, with an insertion shaft; a locking bar disposed inside said plug type receiving member, said locking bar being rotatably movable.

15. The chair according to claim 14, wherein said backrest is pivotally coupled to said seat support.

16. The chair according to claim 14, wherein said seat is coupled to said seat support for movement synchronously with said backrest.

17. The chair according to claim 14 being an office chair.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) Embodiments of the invention are explained in greater detail below with reference to the drawings, in which:

(2) FIG. 1 is a schematic side view of an office chair with joined support members of a backrest support,

(3) FIG. 2 is a cutout of the two-piece backrest support in a pre-insertion position,

(4) FIG. 3 is a view according to FIG. 2 of the plug type connection of the support members of the backrest support in the insertion position without any locking,

(5) FIG. 4 is a view according to FIGS. 1 and 2 of the locked plug type connection of the two support members with the locking bar which is pivoted into the locking position,

(6) FIG. 5 is a perspective partial view of a structural embodiment of the backrest support in the pre-insertion position of the insertion shaft of the backrest-side support member in front of the plug type receiving member of the seat-support-side support member,

(7) FIG. 6 is a perspective cutout of the embodiment according to FIG. 5 when viewed in the plug type receiving member of the seat-support-side support member,

(8) FIG. 7 is a perspective cutout of the embodiment according to FIG. 5 with a backrest support which is connected and locked when viewed from below in the direction towards an unlocking opening in the seat-support-side support member,

(9) FIG. 8 is a schematic side view of an office chair according to FIG. 1 with a variant of the plug type connection with joined support members of the backrest support, and

(10) FIG. 9 is a front view of an office chair according to FIGS. 1 and 8 with armrests which are joined in corresponding plug type connections including locking.

(11) Components which correspond to each other are given the same reference numerals in all the Figures.

DESCRIPTION OF THE INVENTION

(12) FIG. 1 is a schematic side view of an office chair 1. The office chair 1 has a seat or a seat face 2 and a backrest 3 and is supported by means of a chair column 4 by a foot frame which is not shown. The office chair 1 may further have armrests which are not shown and which form a functional unit with the backrest 3.

(13) A backrest support 5 which supports the backrest 3 and to which the armrests are where applicable secured so as to be able to be inserted and locked can be pivoted by means of a rotary bearing 6, that is to say, mounted on a seat support 7 so as to be able to be inclined backwards. Between the backrest support 5 and the seat support 7 there may be provided in a manner not shown in greater detail a synchronization mechanism which enables a synchronous movement of the seat face 2 during an inclination of the backrest 3 in a backward direction.

(14) The backrest support 5 is substantially or approximately L-shaped with a vertical L-shaped member 5a and an L-shaped member 5b which extends in a substantially horizontal manner below the seat face 2. In the shaded partially sectioned transition region of the two L-shaped members 5a, 5b, the backrest support 5 is constructed in two pieces with a seat-support-side (first) support member 8 and a backrest-side (second) support member 9 being formed. The two support members 8, 9 are joined in a positive-locking plug type connection 10 and locked therein by means of a locking bar 11.

(15) As shown in FIGS. 2 to 4 as an enlarged cutout of the region of the plug type connection 10 between the two support members 8 and 9, the seat-support-side support member 8 has a plug type receiving member 12 in which the locking bar 11 is arranged with the articulation end thereof in a rotary bearing 13 so as to be pivotably movable. A resilient element 14 is also arranged inside the plug type receiving member 12 and is supported at that location on the one hand on an inner wall 15 of the plug type receiving member 12, which inner wall faces the seat face 2 and, on the other hand, on the locking bar 11. The locking bar 11 is located with the articulation end thereof in the region of a stepped contour 16 within the plug type receiving member 12 in such a manner that the locking bar 11 in the inwardly pivoted state shown in FIG. 3 is in alignment with an insertion wall 17 between an insertion opening 18 and the rotary bearing 13. That is to say, the inwardly pivoted locking bar 11 completely releases the plug type receiving member 12, that is to say, a corresponding insertion channel inside the plug type receiving member 12 of the seat-support-side support member 8.

(16) The backrest-side support member 9 of the backrest support 5 has at the joint side an insertion shaft 19 whose outer diameter is adapted to the clear width of the plug type receiving member 12 of the backrest-side support member 8 in order to produce a positive-locking connection in the plug type connection 10. Inside the insertion shaft 19, there are provided at the side thereof facing the locking bar 11 a locking contour 20 with an abutment ramp 21 which extends obliquely, that is to say, which declines in an oblique manner in the insertion direction 21, and a locking ramp 22 which merges with the abutment ramp 21 in the region of a ramp base 23. The locking ramp 22 rises in the insertion direction 21 in a suitable manner in a circular manner or declines counter to the insertion direction 21 shown towards the ramp base 23.

(17) During the production of the plug type connection 10 between the two support members 8, 9 of the two-piece backrest support 5, the insertion shaft 19 moves inside the plug type receiving member 12 into abutting contact with the locking bar 11. As a result, the locking bar 11 is pivoted into the pivoted-in position thereof shown in FIG. 3. To this end, the insertion shaft 19 is provided at the free end side with a concave outer contour 24. As soon as the insertion shaft 19 has completely passed the locking bar 11 with the locking contour 20 thereof and in this instance the ramp end 25 of the locking ramp 22, which end is applied to the ramp base 23, has passed the free end 26 of the locking bar 11, the locking bar 11 falls into the wedge-like locking contour 20 of the insertion shaft 19. During this pivot movement of the locking bar 11, it slides with the free end 26 thereof along the locking ramp 22. In this instance, it conforms to the pivot radius of the locking bar 11 as the ramp depth increases in the direction of the ramp base 23.

(18) In addition, the insertion shaft 19 is increasingly drawn in the insertion direction 21 into the corresponding plug type receiving member 12 of the corresponding support member 8. In this instance, the locking contour 20 and in particular the path of the locking ramp 22 is constructed in such a manner that the locking bar 11 during its pivot movement into the locking end position draws the insertion shaft 19 into the plug type receiving member 12 in the insertion direction 21. This effect of self-drawing of the support member 9 which has the insertion shaft 19 into the plug type receiving member 12 of the other support member 8 is achieved by means of a corresponding circular configuration of the locking ramp 22 by it conforming to the pivot radius R.sub.11 of the locking bar 11 as the ramp depth increases. The circle which is associated with the pivot radius R.sub.11 of the locking bar 11 and the circle which is associated with the circle of the circular locking ramp 22 with the radius of curvature R.sub.22 are illustrated in FIG. 4. It is possible to see the circle centre points of the circles with the radii R.sub.11 and R.sub.22 spaced apart from each other with the result described that the insertion shaft 19 while the free end 26 of the locking bar 11 slides along the locking ramp 22, the insertion shaft 19 of the support member 9 is increasingly drawn into the corresponding plug type receiving member 12 of the support member 8. This effect with a correspondingly controlled pivoting of the locking bar 11 is supported by the resilient element 14. In this instance, relative movements between the two support members 8, 9 result in movements of the support member 9 which has the insertion shaft 19 in the insertion direction 21 until the locking bar 11 has reached its locking end position.

(19) FIGS. 5 to 7 show a specific structural configuration of the two-piece backrest support 5 with the seat-support-side support member 8 and the backrest-side support member 9 thereof in a preliminary position of the plug type connection 10 between the insertion shaft 19 and the plug type receiving member 12 of the respective support member 9 or 8, respectively. It is possible to see the locking contour 20 in the embodiment, for example, formed by two struts 20a, 20b which are spaced apart from each other and on which the abutment ramp 21 and the locking ramp 22 are formed.

(20) FIG. 6 is a view into the plug type receiving member 12 of the seat-support-side support member 8. It is possible to see the in this instance plate-like locking bar 11 shown in the pivoted-out position thereof according to FIG. 2. The stepped contour 16, behind which the locking bar 11 during the production of the plug type connection 10 pivots in against the inner wall 15 of the plug type receiving member 12, is provided in this instance by a rod-like or strut-like formed element 27 which is formed on the corresponding inner wall 15 of the plug type receiving member 12 of the seat-support-side support member 8. In the inner wall 28 of the plug type receiving member 12, which wall is opposite this inner wall 15 and the insertion wall 17, there is introduced an access opening 29 for a tool by means of which the plug type connection 10 between the two support members 8 and 9 of the backrest support 5 can be unlocked.

(21) In the locked plug type connection 10 shown in FIG. 7 between the two support members 8 and 9 of the backrest support 5, the insertion shaft 19 is accessible in the region of the web-like construction of the locking contour 20 thereof via the access opening 28. In this instance, there is formed between the webs 20a, 20b which together form the locking contour 19 at the opposite side a gap-like or slot-like unlocking opening 30, by means of which the locking bar 11 is accessible by means of a tool and can be manually pivoted into the unlocking position thereof shown in FIG. 3. If the plug type connection 10 is unlocked in this manner, the backrest 3 together with the backrest-side support member 9 can be released from the seat-support-side support member 8.

(22) The invention is not limited to the embodiments described above. Instead, other variants of the invention may also be derived therefrom by the person skilled in the art without departing from the subject-matter of the invention. In particular, all the individual features described in connection with the embodiments can further also be combined in a different manner, without departing from the subject-matter of the invention.

(23) For example, according to the variant shown in FIG. 8, the plug type receiving member 12 may also be provided on the backrest-side support member 9 and accordingly the insertion shaft 19 may be provided on the seat-support-side support member 8.

(24) In addition, the locking bar 11 may also be constructed as a locking hook which in the opposite insertion direction 21 with respect to FIG. 2 is shown so as to extend obliquely in the initial position thereof in order during the production of the plug type connection 10 to again be deflected against the inner wall 15 or against the insertion wall 17 of the plug type receiving member 12 and with corresponding insertion positioning to slide with the hook end thereof along the locking ramp 22 against the ramp base 23. The effect of the self-drawing of the insertion shaft 19 into the corresponding plug type receiving member 12 is thereby achieved again.

(25) Furthermore, with an office chair 1 which is provided according to FIG. 9 with armrests 31, these can also be mounted without any tools on the armrest support 5 with an identical plug type connection 10 including locking by means of a corresponding locking bar 11 which is preferably supported by means of a resilient element 14.

LIST OF REFERENCE NUMERALS

(26) 1 Chair/office chair 2 Seat face 3 Backrest 4 Chair column 5 Backrest support 5a Vertical L-shaped member 5b Horizontal L-shaped member 6 Rotary bearing 7 Seat support 8 Seat-support-side support member 9 Backrest-side support member 10 Plug type connection 11 Locking bar 12 Plug type receiving member 13 Rotary bearing 14 Resilient element 15 Inner wall 16 Stepped contour 17 Insertion wall 18 Insertion opening 19 Insertion shaft 20 Locking contour 20a,b Strut 21 Abutment ramp 22 Locking ramp 23 Ramp base 24 Outer contour 25 Ramp end 26 Free end 27 Formed element 28 Inner wall 29 Access opening 30 Unlocking opening 31 Armrest