HYDRAULIC CONTROL DEVICE FOR AUTOMATIC TRANSMISSION FOR VEHICLE HAVING CLUTCH DISENGAGE CONTROL MEANS INDEPENDENT OF CLUTCH ENGAGE CONTROL MEANS

摘要

For an automatic transmission for a vehicle such as an automobile having a speed stage shifting mechanism including parallelly arranged first and second hydraulically operated input clutches and adapted to provide the 3rd speed stage in which the first and second input clutches C1 and C2 are both engaged and the overdrive 4th stage in which the clutch C1 is disengaged and the clutch C2 is engaged, the engagement of the clutch C1 in the 3rd speed stage being not essential unless engine brake availability is required, a hydraulic control device has a hydraulic pressure supply control means for variably controlling speed of supply of a hydraulic pressure to the first input clutch C1 according to conditions for engaging the first input clutch such whether it is a kickdown of an overdrive inhibition, and a hydraulic pressure exhaustion control means for controlling speed of exhaustion of a hydraulic pressure from the first input clutch C1 independently of the hydraulic pressure supply control means to be substantially higher than the speed in the supply.