| 摘要 |
The invention is concerned with a continuously variable transmission mechanism which incorporates a variator and an epicyclic gearset. Several brakes and/or clutches are arranged for selectively coupling together or holding stationary various parts of the mechanism to provide forward and reverse transmission ranges within which the overall transmission ratio can be varied by the variator. In a first mode of operation the drive is through the variator, the epicyclic gearset acting as a reduction gearing and a further reduction gearing to an output co-axial with the input. In a second mode, the gearset is locked up to provide direct drive from the variator output to the reduction drive. The ratio of the reduction drive corresponds to the maximum step-up ratio of the variator so that in the second mode, with maximum variator step up ratio the overall transmission ratio is 1:1 in a third mode the input is coupled directly to the output to bypass the variator and provide direct drive. The epicyclic gearset can be used in a reverse mode to provide a reverse gear. |
