Power transmission system

摘要

There is provided a power transmission system which is capable of positively preventing a driver from having a feeling of inertia travel due to torque transmission interruption during an up-shifting operation, simply by using synchromeshes alone and without increasing the axial length of a transmission. This power transmission system includes first to third gear pairs (GP1-GP3) each having an input gear (GI) arranged on an input shaft (14) and an output gear (GO) arranged on an output shaft (15), and first to third synchromeshes (SR1-SR3) each capable of performing disconnecting operation for disconnecting a corresponding one of the first to third gear pairs from the input shaft or the output shaft, baulking operation for power transmission until rotations of the corresponding one of the gear pairs and the input shaft or the output shaft are synchronized, and connecting operation for connecting between the corresponding one of the gear pairs and the input shaft or the output shaft by meshed engagement. When the speed position of the transmission is shifted from the M-th speed position to the L-th speed position, the third synchromesh is caused to move toward the third gear pair by a first predetermined amount which is not large enough to cause the third synchromesh to engage with the third gear pair, to thereby transmit the driving force of the input shaft to the output shaft.