Hyundai Motor Company

Hyundai Notor Company

Joon-Bae Kim

Jae-Duk Jang

Jong-Sool Park

Chang-Wook Lee

Jin-Hee Lee

Tae-Kyun Kim

Disclosed is a hydraulic control system for an automatic transmission that controls a powertrain, which includes a first friction element for use as an engine brake for discontinuing operation of a one-way clutch in the transmission and a second friction element operating only when the first friction element is disengaged. The hydraulic control system comprises a manual valve including a forward range port for exhausting hydraulic pressure when driving in a forward range, and an L range port for exhausting hydraulic pressure for low speed control; and a switch valve controlled by engine brake signal pressure, solenoid pressure, and forward range pressure supplied from the forward range port, the switch valve selectively supplying control pressure to the first friction element and the second friction element.

Hydraulic control system for automatic transmission

This invention provides a hydraulic control system for controlling a power train including four clutches and two brakes, wherein a first pressure controlled by a first solenoid valve is selectively supplied to two clutches of the power train under control of a first switch valve, a second pressure controlled by a second control valve is selectively supplied to another clutch and a first brake of the power train under control of a second switch valve, hydraulic pressure from a port of a manual valve is supplied to yet another clutch via a control valve, hydraulic pressure from another port of the manual valve is supplied to a second brake via another control valve, and the two control valves are controlled by a third solenoid valve.

Growing community of inventors

Seongnam, South Korea

Joon-Bae Kim