Multi-speed transmission

摘要

A multi-speed transmission having a plurality of forward speed gear trains and at least one reverse speed gear train wherein two parallel shafts, one fixed and the other movable along its axial direction, are mounted within the transmission casing. Shifting forks are mounted on said shafts to selectively engage the forward and reverse speed gear trains. For example, for a multi-speed transmission having five forward speeds and one reverse speed, a first shift fork is slidably mounted on a stationary shaft to selectively engage the first and second gear trains, a second shift fork is slidably mounted on the slidable shaft to selectively engage the third and fourth gear trains and a third shift fork is mounted on the slidable shaft so as to be slidable in only one direction to engage the fifth speed gear train. Movement of the slidable shaft in the direction opposite that which engages the fifth speed gear train acts to engage the reverse speed gear train. The shift forks are retained in their selective position by retaining mechanisms which have retractable protrusions engageable with notches in the shafts.