| 摘要 |
<p>An improved four-wheel-drive system transmit driving power to front and rear wheels which includes a viscous coupling (600), a sub-transmission (500) of a continuously variable type provided in one of the driving axles, and an actuator variably controlling the change gear ratio of the sub-transmission (500) to control the ratio of driving power distributed between the front and rear wheels. The power distribution ratio is changed suitably to both the driving conditions and the road surface conditions. Further this four-wheel-drive system is lightweight and with low vibration in comparison with the conventional type using a center differential.</p> |
