CONTROL SYSTEM FOR AN AUTOMATIC TRANSMISSION

摘要

An automatic transmission shift control system includes a hydraulically controlled valve mechanism for connecting and disconnecting a supply of hydraulic pressure to frictional coupling elements. Connection and disconnection of the hydraulic pressure supply locks and unlocks the frictional coupling elements in order to automatically shift an automatic transmission into desired gears. A time regulator regulates a duration time for which the valve mechanism is kept actuated and with which a speed at which the frictional coupling element is locked changes. The time regulator is controlled so as to variably regulate the duration time according to conversion efficiency of a torque converter. This conversion efficiency is, for example, determined from a speed conversion ratio and a torque conversion ratio.