| 摘要 |
<p>A continuously-variable-ratio transmission ('CVT'), especially of the toroidal-race rolling-traction type, in which the prime mover is connected to the ratio-varying component ('variator') by a torque converter (1) or other starting device capable of slip. The CVT output (36) is connected both to the variator output (23) and also, by way of fixed ratio gearing (37, 38) and a one-way clutch (53), to the output of the starting device. At low speeds drive is transmitted from primer mover to the CVT output by way of the fixed ratio gearing in both forwards and reverse. In forward drive, as the speed of the variator output rises, operation of the one-way clutch (53) causes the drive transmission path to change from the fixed ratio gearing to the variator output once the speed of the latter exceeds the former. Where the variator is of the toroidal-race type, further one-way clutch means (54) may be included to ensure that the fixed ratio gearing components can rotate in one direction only, thus preventing them from imposing reverse rotation upon the essentially unidirectional variator components.</p> |
