| 摘要 |
PURPOSE:To eliminate hunting phenomenon, by setting the width of hysteresis such that the engine rotation for switching from direct-coupled driving the continuously variable driving is lower than the engine rotation for switching from continuously variable driving to direct-coupled driving. CONSTITUTION:When the speed change ratio of a continuously variable speed change path reaches to a direct-coupled transmission ratio, a start clutch 20 is disengaged while a direct-coupled clutch 5 is engaged so as to switch to direct-coupled driving. During said direct-coupled driving, a continuously variable transmission 10 is controlled to the optimal speed change ratio at the lower speed ratio side than the highest speed ratio so as to idle the continuously variable transmission 10 turns reducing the loss torque. When it is switched from direct-coupled driving to continuously variable driving, a hysteresis width corresponding to the throttle opening is set below the target engine rotation and it is controlled such that the continuously variable transmission is not switched to the continuously variable speed change driving until the engine rotation drops below said hysteresis width. In such a manner, hunting phenomenon can be prevented. |
