| 摘要 |
Shifting device for a turning gear transmission having an automatic change of transmission ratio when a change in direction of a driving shaft occurs, including two driving gearwheels disposed coaxially with respect to the driving shaft, the driving gearwheels being of different diameters and, respectively, being disconnectable from the driving shaft, and a driven shaft having two driven gearwheels firmly connected thereto and being in continuous pair-wise engagement with the driving gearwheels, further includes a pawl holder rotatably mounted on the driving shaft, the driving gearwheels being rotatably mounted on the pawl holder, at least one pair of pawls held by the pawl holder, and a device for causing the pair of pawls, contingent upon the respective direction of rotation of the driving shaft, to effect an entrainment of one of the driving gearwheels in a different direction of rotation. |
