Abstract: An automatic transmission system for automotive vehicle includes a hydraulic pump for pressurizing fluid, a pressure regulating valve for varying hydraulic pressure supplied from the hydraulic pump, nine friction elements activated by drive pressure or reverse pressure supplied from a manual valve, first and second shift control sections having at least two shift valves for supplying hydraulic pressure to the friction elements, selectively, and a torque pressure converting section for supplying torque pressure to the first shift control section. The system performs five forward speeds and one reverse speed. Two solenoid valves are adopted to control four shift valves and control is performed sequentially such that the construction of the system can be simplified and the shift feeling can be improved.

Abstract: A hydraulic control system of automatic transmission for vehicles includes a torque converter control part having a damper clutch control solenoid valve and a regulator valve; a manual valve for supplying an oil pressure to another lines according to a shift lever's position; a first, a second, and a third indirect control valves, to which the oil pressure is supplied if the manual valve is set in drive "D" range; a first, a second, and a third solenoid valves, each of which controls the indirect control valves, respectively; a first friction element communicating with the first indirect control valve; a second friction element communicating with the second indirect control valve; a third friction element communicating with the second indirect control valve; a fourth friction element communicating with the third indirect control valve; a switch valve for supplying an operating pressure to the second friction element in drive "D" range and supplying the operating pressure to the third friction element in "L" r