| 摘要 |
A safety crank for a winch drive or the like, comprising one or more ratchet wheels lying in a housing and provided with teeth and several spring-supported pawls engaging in the teeth, is designed according to the invention in such a way that at least two pawls (4) engage simultaneously and completely in the teeth (7) and are supported in each case on a tooth face (13), the number of teeth (7) corresponding to an even multiple of the number of engaging pawls (4). In this arrangement, four pawls (4), for example, can be provided which are arranged at equal angular distances from one another and of which in each case two diametrically opposite pawls (4) engage simultaneously in the teeth (7) of the ratchet wheel (2), while the other two pawls (4) are supported with their backs on tips of the teeth (7). On the one hand this ensures that the load acting on the corresponding engaged teeth (7) is halved just as the load acting on the pawls (4) is halved, and on the other hand the return distance of the crank (11) corresponds to the range which has to be covered until the next opposite pawls (4) come into engagement. Here, the ratio of the number of engaging pawls (4) to the number of pawls (4) not in engagement determines the return distance. <IMAGE>
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