| 摘要 |
A lock-up type automatic transmission having a lock-up clutch between the pump impeller and the turbine runner of the torque converter. Control means for engaging and disengaging the lock-up clutch includes a lock-up control valve, a solenoid valve to control the shifting of the lock-up control valve, lock-up decision circuit means for producing a lock-up permission signal, shifting operation detector circuit means for producing a shift pulse signal, and a solenoid valve control means for controlling the solenoid valve to effect engagement of the lock-up clutch under conditions when the lock-up permission signal is present and the shift signal is not present, but to effect temporal disengagement of the lock-up clutch in response to the presence of the shift signal even when the lock-up permission signal is present. A delay means is provided to retard the appearance of the shift signal from the appearance of a demand for the shifting from one gear ratio to another gear ratio. |
