CONTROLLER FOR VEHICLE AUTOMATIC TRANSMISSION

摘要

PROBLEM TO BE SOLVED: To provide an automatic transmission which a controller can terminate shifting motion adequately even if a signal is abnormal in order to calculate an input shaft torque required for the automatic transmission shifting control. SOLUTION: In the automatic transmission 2, the controller can calculate an input shaft torque required eventually so that the hydraulic pressure required for shifting control does not come under the lower limit by fixing a torque ratio to the maximum upper limit of the shifting execution range if the input shaft torque is not figured out due to that either an engine revolution Ne or an input shaft revolution Nt of torque converter 10 is abnormal. Therefore, the controller can secure required control hydraulic pressure corresponding to engaging force for the friction engagement element in the automatic transmission 2 if sensors fitted to either transmission side or engine side is abnormal and it is characterized that the damage to friction engagement element is prevented terminating shifting motion within the predetermined time limit without shortage of the engaging force in the shifting control of the automatic transmission 2.