| 摘要 |
1,211,383. Castors. TENTE-ROLLEN G.m.b.H. & CO. 10 Nov. 1967 [21 Jan., 1967], No. 51199/67. Heading A4U. [Also in Division F2] In a castor a pivoted, laminated-spring, brake lever 10, having a tongue 13 for engaging the wheel rim, and a catch 11 for engaging ratchet teeth 12 on a ballbearing housing 5 surrounding the swivel axis, is operated to simultaneously lock the wheel against rolling and swivelling by a bolt 19 which is pressed continuously by the brake lever and which is projected by a foot-operated push button 18 against the action of a spring tongue 14 to a brakeoperating position in which it is latched. The bolt is released by a further operation of the push button in the same direction. An actuator housing 21, for the bolt and latching mechanism, is screwed into a tapped bore in an arm 16 riveted to the castor housing and secured in position of adjusted locking pressure by a checknut 22. The latching mechanism, of a type used in retractable ball point pens, includes a rotatable toothed shift sleeve 20 with internal splines and axial teeth at both ends, projections at different heights on the non-rotatable bolt 19 co-operating with the splines and ratchet teeth during movement of the bolt to rotate the sleeve by one ratchet tooth and alternately lock and release upward movement of the bolt. In modifications, the rotary member of the latching mechanism is a toothed disc or includes a pin or ball in a guide groove or a swivelling coupling pin. In further modifications the brake lever is a rigid rocker continuously biased by a spring, or is effective to prevent either rolling or swivelling of the wheel. |
