Automatic variable transmission and hydraulic control system thereof

Abstract

An automatic variable transmnission, and a hydraulic pressure control system for the same, have a structure which can be installed in both rear and front wheel drive vehicles. The transmission includes: a torque converter which is connected to an output shaft of an engine and which converts and transfers torque from the engine; an input shaft connected to the output shaft of the torque converter; first and second planetary gearsets which are located between the input shaft and an output shaft; a first clutch which selectively locks a sun gear of the second planetary gearset to the input shaft; a second clutch which selectively locks the input shaft to the planetary pinion gear carrier of the first planetary gearset; a third clutch for selectively connecting the input shaft with a sun gear of the first planetary gearset; a first brake for selectively restricting the rotation of the sun gear of the first planetary gearset; a second brake for restricting rotation of both the ring gear of the second planetary gearset and the planetary pinion gear carrier of the first planetary gearset; and a one-way clutch to limit the rotational direction of the ring gear of the second planetary gearset and the planetary pinion gear carrier of the first planetary gearset.