| 摘要 |
A step-by-step ratchet mechanism has a mount, a hand lever that is carried on the mount and is pivotal about an axis of the hand lever, and a ratchet that is provided with a toothed set wheel and with an output shaft that is rotatable about an axis of the ratchet in the mount. Two catches are provided, they a) are each hinged on the hand lever and are pivotal around an axis of the catch, b) are each provided with a gear cutting that cooperates with the set wheel, c) are provided with a supporting flank that neighbors an abutment of the mount and d) are provided with a first elastic means that resiliently pretensions the two supporting flanks towards the abutment. Each catch is further provided with e) a pin. The gear cutting is designed as a toothed quadrant with several teeth. Two mean position levers are carried on the mount and are each pivotal about an axis of the mean position levers, one mean position lever being assigned to each catch. The mean position levers are provided with a stop flank. A stop area of the hand lever is provided and is arranged adjacent to each of said stop flanks. A second elastic means is allocated to the two mean position levers, said elastic means resiliently pretensioning the stop flank against each stop area. The mean position levers are provided each with a guide bight which is designed for receiving and guiding the pin of the corresponding catch. Each guide bight is arranged in such a manner that its aperture faces the aperture of the other guide bight.
|
