LOCKING DEVICE FOR CHAIR SEATS

Abstract: Device for locking in a chair seat in a desired angular position, comprising several lamellae (1) connected with the seat, extending through a retainer (7) and between fixed lamellae (2) arranged in the retainer, whereby clamping shoes (3, 4) which are abutting against the outer fixed lamellae (2) may be clamped by bolts (5, 6) for locking the position of the seat and providing possibility for adjustment of the clamping points of the bolts, where lameellae (1) without holes are arranged abutting against fixed lamellae (2) across their width, the lamellae (1) being connected with the seat of the chair, the fixed lamellae (2) being captured by the retainer (7) and the bolts (5, 6), each provided with a clamping shoe (3, 4) and aligned axially.

Description: Locking device for chair seats Present invention is related to a locking device for a chair seat with adjustable angle according to the preamble of the claim. Several principles are known for adjustment and locking the angular position of seats, especially of office chairs. For a long time it already has been known to use arcuated lamellae secured to the underside of the seat and guided be- tween lamellae blocks in a retainer which again is secured to the base of the chair, whereby a bolt is extending through a centric hole in the lamellae block and a slot in all lamel¬ lae. Locking of the seat in a desired position was provided by clamping the lamellae and the lamellae block together where- by the abutment surface which was necessary to achieve suffi¬ cient friction in relation to the force from the locking mechanism, was provided by the width of the lamella on both sides of the slots as well as their number. In known embodiments the width or the number of lamel- lae must be grater due to the slot, thereby to achieve the necessary friction surface in relation to the force which can be expected in connection with the clamping. Additionally manufacturing of the slots in the lamellae and the holes in the fixed lamellae made necessary an additonal operation in the production. Also the assembling consumed additional time for bringing the bolt through the holes in the fixed lamellae and the slots for clamping the lamellae against a fixed abut¬ ment. No consideration was made as to tolerances in the produc¬ tion in connection with the assembling of the lamellae. With the locking device according to the present inven¬ tion the above mentioned disadvantages by known corresponding devices are avoided and there is provided a possibility for adjustment of a desired position of the lamellae in the retai¬ ner as well as a possibility for later adjustment of the posi- tion of the operation handle when the locking device is brought in clamping position. These advantages are achieved with the locking device according to the invention as described with the features stated in the claim. In the drawing Fig. 1 discloses a section along I-I in Fig. 3, Fig. 2 discloses a section along II-II in Fig. 1 and Fig. 3 discloses a view from the right side in Fig. 1. Several arcuated lamellae 1 are secured to the under¬ side of a chair seat and protude through a retainer 7 secured to the base of the chair. In the retainer are arranged retai¬ ning lamellae in such a way that all arcuated lamellae 1 are kept between fixed lamellae. The fixed lamellae 2 are provided with recesses to be received by the side edges of the retainer 7 in such a way that the lamellae to are captured in the retai¬ ner 7. Against both sides of the lamella package are arranged preferably a cup shaped clamping shoe 3, 4 abutting with pre¬ ferably an annular surface against a retaining lamella 2. A bolt 5 is arranged through a hole in the retainer 7 and connected turnable with the clamping shoe 3 in such a way that the clamping shoe 3 by turning of the bolt 5 may be dis¬ placed against or away from the outer lamella 2. Upon desired adjustment of the bolt 5 by means of threads 6 , the bolt may be secured with a nut (not shown). Againt the opposite side of the lamella package a clamping shoe 4 is abutting against the lamella 2 whereby a bolt 8 releasably is connected with the clamping shoe 4 and threaded through a hole in the retainer 7. The bolt 8 conveniently is extended to the side of the chair and a opera¬ tion arm 9 is secured to the end of the bolt 8 suitably in a place for operation by the user. Turning of the operation arm 9 will press the clamping shoe 4 against the lamella 2. By adjustment of the bolt 5 the locking device may be adjusted upon wear of the lamella and a desired position of the operation arm 9 may be achieved by adjustment. In the same way desired position of the lamellae in the retainer may be adjusted by adjusting the bolts 5 and 8.

Claims: P a t e n t C l a i m Device for locking in a chair seat in a desired angu¬ lar position, comprising several lamellae (1) connected with the seat, extending through a retainer (7) and between fixed lamellae (2) arranged in the retainer, whereby clamping shoes (3, 4) which are abutting against the outer fixed lamellae (2) may be clamped by bolts (5, 6) for locking the position of the seat and providing possibility for adjustment of the clamping points of the bolts, CHARACTERIZED IN lamellae (1) without holes are arranged abutting against fixed lamellae (2) across their width, the lamellae (1) being connected with the seat of the chair, the fixed lamellae (2) being captured by the retainer (7) and the bolts (5, 6), each pro- vided with a clamping shoe (3, 4) and aligned axially.

Inventors: HOLSTENSSON LARS, LIE TORE, HOLSTENSSON, LARS, LIE, TORE
Applicants: RING MEKANIKK AS, RING MEKANIKK A.S.
Application year: 1989
Main classification: A47C3
IPC codes: A47C1, A47C3