SOLENOID VALVE AND HYDRAULIC PRESSURE CONTROL DEVICE FOR CLUTCH MECHANISM USING IT

摘要

PROBLEM TO BE SOLVED: To provide a solenoid valve physically small to detect malfunction. SOLUTION: A solenoid valve 30 is a hydraulic pressure control valve to adjust pressure of working oil pumped up from a tank 56 by a pump 55 and to apply it on a clutch 20. A spool 37 stops at a position where energizing force of a spring 38, electromagnetic force generated on a coil 47 by an electric current supplied to the coil 47 and force which the spool 37 receives from pressure of a feedback chamber 39 are balanced. When a plunger 42 makes contact with a stopper 50, an electric potential of a terminal 51 becomes an earth electric potential, and when the plunger 42 aparts from the stopper 50, the electric potential of the terminal 51 becomes an electric power source electric potential. It is possible to speedily detect completion of filling as an ECU 54 detects from pressure rise the feedback chamber 39 in filling control that the plunger 42 aparts from the stopper 50 and the electric potential of the terminal 51 becomes the electric power source electric potential.