摘要 |
In a fluid pressure control system for a continuously variable transmission, a valve for regulating a torque converter pressure is a pilot actuated valve having a pressure increasing side pilot port for receiving a control pilot pressure for controlling a line pressure and a pressure decreasing side pilot port for receiving a second pilot pressure. A selector valve is switched between a first state for allowing the supply of the second pilot pressure to decrease the torque converter pressure supplied to the torque converter and a second state for draining the second pilot pressure to increase the torque converter pressure. By controlling the selector valve, a control unit increases the torque converter pressure in a wide throttle high speed vehicle operation with the torque converter in a lockup state to ensure the lockup engagement and in a wide throttle starting operation with the torque converter in a non-lockup state to prevent an engine stall. Otherwise, the control system decreases the torque converter pressure to improve the fuel economy.
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