| 摘要 |
PURPOSE: To effectively suppress shift shock in the case of releasing lock-up regardless of causes of downshifting by judging whether or not the downshift is caused by rise in engine load and releasing the lock-up at slower speed in the case of judging NO than that in the case of judging YES. CONSTITUTION: A control unit reads respective kinds of signals in traveling of a vehicle and when a duty ratio of a control signal to a lock-up solenoid valve 51 is 100% and a downshift flag is 1, downshift is performed and at the same time the lock-up clutch 29 is disengaged. However, when the downshift is caused by abrupt increase in a throttle opening, the duty ratio of the control signal to the lock-up solenoid valve 51 is changed from 100% to 0%. This constitution can release lock-up quickly so as to prevent shift shock caused by lock-up delay in downshifting. |
