| 摘要 |
A first body 7 which may be part of a crane is driven in rotation relative to a body 1 through a lost motion device and, for example, by a pinion 3 engaging with a toothed rim 2 attached to the body 7. The lost motion device may comprise lugs 10 and 11 fixed to the bodies 7 and 1 respectively, and a freely rotatable arm 9 mounted coaxially of the two bodies. When the lug 10 on the driven body abuts the arm 9 on one side, the arm 9 is driven until it abuts the lug 11 on the stationary body 1, further rotation then being prevented. However, when this position is reached, reverse rotation is possible through a limited angle which is greater than one revolution. <IMAGE> |
