| 摘要 |
<p>The invention concerns a device arranged to effect step-by-step turning movement of a stand by means of a piston-and-cylinder unit (13) which performs a reciprocating movement during each operational stroke. For the purpose of obtaining control of movements and retainment of the stand (1) during standstills as well as during turning movement of the latter, the device comprises an actuating arm (15) which is pivotable about the centre of the stand, and a carrier member (16) which moves together with the actuating arm (15) and, during turning movement of the stand over the intended distance, abuts against one of a number of fixed impact edges (9-12) spaced peripherally around the stand. The device also comprises stop means comprising two opposite spring-biased shoulders (18, 19) arranged upon completion of a turning movement of the stand to lock between said shoulders the immediately subsequent, advanced impact edge (9-12) while the actuating arm (15) performs its return movement and the carrier member (16) passes said subsequent impact edge (9-12) and assumes a position behind the latter.</p> |
