| 摘要 |
<p>A rocker mechanism (10) preferably intended for rotatable arm chairs, comprising an upper part (12) which is attached to a seat and which is pivotally journalled to an underpart (14) by means of a horizontal pivot shaft (24), the underpart being carried by the vertical supporting pin of, for example, a rotatable arm chair. The underpart presents an upstanding holder (36) having a throughpassing opening (38) for accommodating a locking rod (48) provided with a handle and extending parallel with the pivot shaft (24), and promontories (40) which have a trapezium-shape cross section and which are intended for abutment with recesses (41) in two clamping plates or jaws (76) located on a respective side of the hoder. The locking rod (48) is journalled in bearing blocks (58) on the upper part (12) and presents a lefthand screwthread (50) and a righthand screwthread (52) which co-act with respective screwthreaded holes (51 and 53) provided in the clamping plates or jaws (76). The promontories (40) of the holder and the corresponding recesses (41) of the clamping plates present curved surfaces (44, 46 and 45, 47) the centre of curvature of which islocated in the pivot centre of the pivot shaft (24).</p> |
