Clutch hydraulic controller

A clutch hydraulic controller comprising:

• a hydraulic actuator, which engages and disengages a clutch;
• regulator valve means, which adjusts and sets a line pressure;
• an electrically controlled valve, which produces a valve control pressure in correspondence to an electrical control signal;
• correspondent pressure generating means, which produces mechanically a correspondent pressure that corresponds to rotational speed of an engine;
• a clutch pressure control valve, which adjusts said line pressure by using said valve control pressure or said correspondent pressure and supplies this adjusted line pressure to said hydraulic actuator;
• a shift restriction valve, which draws selectively either said valve control pressure or said correspondent pressure;
• and
• fault determining means, which determines existence of a fault;
• wherein:
• as long as said fault determining means determines that said hydraulic controller is operating normally, said shift restricting valve restricts said correspondent pressure to said clutch pressure control valve and said line pressure is adjusted by said clutch pressure control valve using said valve control pressure directly, for setting said clutch control pressure;
• and
• if said fault determining means determines that there is a breakdown, then said line pressure is adjusted by said clutch pressure control valve using said correspondent pressure being supplied through said shift restricting valve instead of using said valve control pressure, for setting said clutch control pressure.