Twin-clutch type transmission unit for engine, and motorcycle incorporating the same

摘要

A twin-clutch type transmission unit includes inner and outer shafts provided respectively with first and second disc clutches for transmission and interruption of input from a prime mover, a plurality of drive gears provided on the inner and outer shafts, and a counter shaft provided with driven gears selectively operable to mesh with the drive gears, with the first and second disc clutches of the inner and outer shafts being alternately disengaged and engaged so as to perform a gear shift. In the transmission unit, a dog-type clutch for synchronizing rotations of the inner shaft and the outer shaft is provided. At the time of vehicle starting, the inner and outer shafts are connected with each other, and the first and second disc clutches of both the inner and outer shafts are engaged. Such transmission unit contrives reductions in the size and weight of a twin-clutch type transmission unit.

主权项

1. A twin-clutch type transmission unit comprising
a first clutch and a second clutch; a first input shaft and a second input shaft provided respectively with said clutches for transmission and interruption of input from a prime mover; a plurality of drive gears provided on the first and second input shafts; an output shaft provided with a plurality of driven gears operable to selectively mesh with the drive gears, with the clutches of the first input shaft and the second input shaft being alternately disengaged and engaged so as to perform a gear shift; and a clutch synchronization device for synchronizing rotation of the first input shaft and rotation of the second input shaft, the clutch synchronization device comprising a first drive gear being rotationally fixed on the first input shaft and a second drive gear being rotationally fixed on the second input shaft, said clutch synchronization device being operative to directly connect the first input shaft and the second input shaft; wherein, at a time of vehicle starting: the first input shaft and the second input shaft are directly connected to each other by said clutch synchronization device, the clutches of both the first and second input shafts are simultaneously engaged, such that motive force from the prime mover is transmitted by the first clutch to the first input shaft and simultaneously by the second clutch to the second input shaft, the motive force transmitted to the second input shaft by the second clutch is further transmitted from the second input shaft to the first input shaft by the clutch synchronization device, a sum of the motive force transmitted from the first clutch to the first input shaft and the motive force transmitted from the clutch synchronization device to the first input shaft is transmitted from the first input shaft to the output shaft, and a loading of the first and second clutches is shared during the time of vehicle starting.