Automatic transmission control system for automobiles

摘要

An automatic transmission control system for an automatic transmission including a hydraulic pressure control circuit which supplies locking and unlocking pressures selectively to a plurality of friction coupling elements to lock and unlock the selected friction coupling elements, changing a torque transmission path in a transmission gear mechanism to provide available gears, a specific one of which is achieved by locking and unlocking simultaneously specific friction coupling elements. During a skip gear change, in particular a 4-1-down-shift, first, second and third pressure regulating means are controlled in a way that 2-4 brake and 3-4 clutch are released in such order as to decrease relative speed between input and output of the forward clutch. A shift shock caused due to the torque draw from a clutch drum rotating in opposite directions will be suppressed.