Speed change control system for automatic transmission

摘要

A speed change control system for an automatic transmission which includes a plurality of frictional engagement elements and in which a first speed change unit for executing a clutch-to-clutch shift by applying/releasing two frictional engagement elements simultaneously and a second speed change unit for executing a speed change by applying a one-way clutch are connected in tandem. The decision is made upon both the clutch-to-clutch shift of the first speed change unit and the speed change, as effected by applying the one-way clutch of the second speed change unit. At the speed change time, the clutch-to-clutch shift is established before the application of the one-way clutch. According to the present invention, therefore, the clutch-to-clutch shift at the first speed change unit of the automatic transmission, as accompanied by the application of the one-way clutch at the second speed change unit, can be easily controlled to prevent the shift shock.