Gas solenoid valve
A gas solenoid valve includes: a housing including a first port, a second port, and a valve port leading to the first port and the second port; a main valve body capable of moving between a closed position thereof closing the valve port and an open position thereof opening the valve port and configured to move in an opening direction from the closed position to the open position by pressure of gas supplied through the first port; a biasing member that provides a biasing force acting in a closing direction to the main valve body to position the main valve body in the closed position; and an electromagnetic drive device that generates an excitation force opposing the biasing force of the biasing member to cause the main valve body to move to the open position. A damping chamber in the housing dampens movement of the main valve body.
1. A gas solenoid valve, comprising:
a housing including a first port, a second port, and a valve port leading to the first port and the second port;
a main valve body capable of moving between a closed position and an open position and configured to move in an opening direction by pressure of gas supplied through the first port, the closed position being a position of the main valve body closing the valve port, the open position being a position of the main valve body opening the valve port;
a biasing member that provides a biasing force to the main valve body to position the main valve body in the closed position, the biasing force acting in a closing direction from the open position to the closed position;
a seat piston that is inserted through the main valve body, receives the biasing force of the biasing member, and biases the main valve body to the closed position; and
an electromagnetic drive device that generates an excitation force to cause the main valve body to move to the open position, the excitation force opposing the biasing force of the biasing member, wherein
a pilot passage connecting the first port and the second port is formed in the main valve body,
the seat piston is capable of moving between a pilot closed position and a pilot open position, the pilot closed position being a position of the seat piston closing the pilot passage, the pilot open position being a position of the seat piston opening the pilot passage,
the electromagnetic drive device includes a plunger through which the seat piston is inserted in a manner to be movable in conjunction, a stationary pole disposed facing the plunger, and a solenoid that provides the excitation force to the plunger to attract the plunger to the stationary pole to cause the seat piston to move to the pilot open position and cause the main valve body to move to the open position,
a damping chamber that damps movement of the main valve body is formed in the plunger, and
the damping chamber that is adjacent to the seat piston and located in the opening direction of the main valve body relative to the main valve body introduces and discharges gas through a gap between the seat piston and the plunger.
2. The gas solenoid valve according to claim 1 , wherein:
the biasing member is disposed in the damping chamber.
3. The gas solenoid valve according to claim 1 , further comprising:
a stopper that limits an amount of movement of the main valve body in the opening direction.