摘要 |
A high efficiency hydraulic control system for a wet dual clutch transmission includes an engine driven hydraulic pump. A first pair of variable feed solenoid valves independently and mutually exclusively provide hydraulic fluid to a respective pair of main or input clutch actuators. A second pair of variable feed solenoid valves provide hydraulic fluid to a pair of inlet ports of a first spool or logic valve. The position of the spool of the first logic valve is controlled by an on-off solenoid valve. A first pair of outlet ports of the first logic valve selectively provide hydraulic fluid to a first three area piston which selects two gear or speed ratios, for example, reverse and third gear. A second pair of outlet ports of the first logic valve selectively provide hydraulic fluid to a pair of inlet ports of a second spool or logic valve. The position of the spool of the second logic valve is controlled by hydraulic fluid from the input clutch circuits. A first pair of ports of the second logic valve selectively provide hydraulic fluid to a second three area piston which selects two other gear or speed ratios, for example, first and fifth gears and a second pair of ports of the second logic valve selectively provide hydraulic fluid to a third three area piston which selects two additional gear or speed ratios, for example, second and fourth gears. |