Fluid control solenoid valve

摘要

A fluid control solenoid valve includes a fluid passage having a valve seat therein. The solenoid valve further includes a bellows having a valve element and a retractable bellows portion continuous with the valve element. The valve element opens the fluid passage when lifted from the valve seat, and closes the fluid passage when seated onto the valve seat. A first spring urges the valve element in a valve lifting direction away from the valve seat, while a second spring urges the valve element in a valve seating direction toward the valve seat. An electromagnetic actuator is further provided for moving the valve element in the valve lifting direction, when energized. The first spring is interposed between an adjusting screw and the valve element. The adjusting screw is arranged to be extended at a high temperature so as to increase a biasing force of the first spring urging the valve element in the valve lifting direction. This prevents a sealing load, which is applied to the valve element to cause it to be seated onto the valve seat, from increasing. Increase in sealing load would be otherwise caused due to thermal expansion of the bellows portion at the high temperature.