Hydraulic control system of automatic transmission

摘要

A hydraulic control system for an automatic transmission comprising a shift speed mechanism, a frictional element hydraulically controlled for switching a power transmitting path in the shift speed mechanism, a working pressure controller for controlling an engaging force of the frictional element during a shift operation by adjusting a working pressure applied to the frictional element, a calculator for calculating separately an input torque pressure corresponding to an input torque introduced to the shift speed mechanism and an inertia torque pressure corresponding to an inertia torque which is changed in accordance with a speed change of the shift speed mechanism, and a learning control compensator for compensating the inertia torque pressure by means of a learning control. The shift shock is effectively suppressed irrespective of the change of the vehicle operating circumstance.