Doppel-Elektromagnetventil

摘要

Provided is a safe, double solenoid type electromagnetic valve which, despite of a double solenoid type, can be used also as a single solenoid type electromagnetic valve and in which a main valve member does not change over from one change-over position to another even when electric power is supplied to two pilot valves at a time. A first piston 18 is disposed at one end of the main valve member 12, while second and third pistons 19, 20 are disposed at the opposite end of the main valve member, the first and second pistons 18, 19 having the same diameter, and the third piston 20 being smaller in diameter than the first and second pistons. Two solenoid mechanisms 30a and 30b are provided for making a pilot fluid operate on the first piston and the second, third pistons, and also provided is a change-over device 6 capable of change-over operation between the case where the pilot fluid is allowed to operate on both second and third pistons and the case where the pilot fluid is allowed to work on only the third piston 20 of a smaller diameter.