Multi-stage gear shift transmission

Abstract

A multi-stage gear shift transmission comprising a plurality of forward stage gear trains capable of being alternatively established, and a reverse stage gear train having an idle gear portion meshed with a reverse input gear and a reverse output gear. The forward stage and reverse stage gear trains are provided between an input shaft and an output shaft parallel to the inut shaft. A reverse stage establishing clutch mechanism is interposed in the middle of the reverse stage gear train. The idle gear portion is divided into a first idle gear meshed with the reverse input gear, and a second idle gear meshed with the reverse output gear and capable of being connected to the first idle gear through the reverse stage establishing clutch mechanism. The reverse stage establishing clutch mechanism comprises a sleeve which is engaged with the first idle gear for relative non-rotation and for axial relative movement and which is capable of being meshed with the second idle gear, a braking member which is disposed between the first and second idle gears for axial movement so that it may be urged toward the second idle gear in response to the movement of the sleeve toward the second idle gear and which is capable of being rotated in unison with the first idle gear, and a stationary part fixedly disposed to temporarily frictionally engage with the braking member when the braking member is moved toward the second idle gear.