| 摘要 |
An planetary gearing in which a planetary gear is positioned at three or more positions. A sun gear and a planetary carrier are co-axially and rotatably arranged. A planetary gear is rotatably supported by the planetary carrier to engage the sun gear. A plurality of transmission gears are arranged around the sun gear to be selectively engaged with the planetary gear when the planetary gear revolves around the sun gear. Stopper projections are provided on the planetary carrier, each corresponding to each of the transmission gears. An engagement lever is rotatably arranged to take a first position and a second position. The engagement lever at the first position holds the planetary carrier, by selectively engaging one of the stopper projections, to make the planetary gear engage the corresponding transmission gear. On the contrary, the engagement lever at the second position is disengaged from the stopper projections. The engagement lever is controlled by a cam member so as to rotate between the first and second positions. The cam member is controlled by a control member so that the engagement lever rotates and stops at the first and second positions. |
