| 摘要 |
An improved shiftable change speed transmission is provided. The improved transmission is preferably provided with at least one countershaft having countershaft gears thereon disposed in meshing engagement with main shaft gears encircling the transmission main shaft. Gears are selectively axially movable relative to the associated shaft by conventional means for effecting shifting of the transmission. The axially movable gears cooperate with clutch rings which surround and are supported on and for rotation with the associated shaft by splines, preferably the clutch rings also are axially movable relative to the associated shaft and are resiliently urged in a direction toward the respective gear with which same cooperates, whereby shifting of the axially movable gear toward its respective clutch ring causes resilient axial movement of the latter until synchronization is achieved to permit the clutch ring to move axially in response to said resilient urging and engage the main shaft gear. The improvement comprises providing spline teeth on the clutch ring or the associated shaft which are of a substantially constantly varying thickness and are arranged such that, when the clutch rings are in the non-axially displaced position, the circumferential spacing betwen cooperating clutch ring and shaft spline teeth is smaller at the axial end of the clutch ring closest to the gear with which it is associated than at the other end of the clutch ring. |
