CONTROL MEANS FOR VEHICLE AUTOMATIC TRANSMISSIONS

摘要

A vehicle automatic transmission including a torque converter and a multiple stage transmission gear mechanism. The gear mechanism is controlled through a hydraulic system having solenoid valves. An electronic control unit is provided to control the hydraulic system under a shift control map having shift up and shift down control lines. The shift down control line is determined in terms of the torque converter turbine speed and the engine throttle valve position as a line in which the torque converter is operated with a torque ratio of substantially one.