Hydraulic control system for a continuously variable transmission with a torque converter

摘要

A high pressure circuit is connected between a secondary pressure control valve and a lockup clutch control valve for actuating a lockup clutch of a torque converter. A low pressure circuit is connected between the lockup clutch control valve and a continuously variable transmission. A high relief valve is provided in the high pressure circuit for controlling the lockup clutch with high pressure. A low relief valve is provided in the low pressure circuit for lubricating a transmission belt so as to improve cooling efficiency.