| 摘要 |
A drive mechanism having a normal, fixed, transmission ratio between an input and an output shaft and having the shafts coupled together by a mechanism which can impart an additional incremental rotation to the output shaft during each revolution thereof. The mechanism includes a wheel having a sawtooth periphery fastened to the end of one shaft and a plate carrying one or a plurality of angularly spaced pawls fastened to the end of the other shaft. The pawls are mounted to resiliently engage in the teeth on the wheel periphery and to be movable along the sloping surfaces thereof. The plate and wheel are relatively shiftable to transversely offset the axes of the input and output shafts to permit such incremental movement to occur. The output shaft can rotate in one direction whether or not the input shaft is rotating, and with the shaft axes offset, the output shaft undergoes such additional incremental movement during each revolution thereof. |
