Control valve device

Claim 1

A control valve device for controlling fluid communication in a fluid passage in response to an input current signals from a switch device and changes in ambient temperature, said control device comprising; a body member having an inlet port and an outlet port, said body having a fluid passage formed therein connecting said inlet port and said outlet port; a valve member disposed in said fluid passage for controlling fluid communication in said fluid passage; yoke means made of a magnetic material and fixedly secured on said body member; an inner core disposed on a central axis in said yoke means; a bobbin made of a nonmagnetic material and disposed on an outer periphery of said inner core; a solenoid coil wound on said bobbin and forming a magnetic circuit with said yoke means and said inner core; a plunger member positioned in said magnetic circuit and disposed on said central axis with said inner core wherein said plunger member is attracted by said inner core upon energization of said solenoid coil; a shaft fixed in said plunger member at a first end and operatively associated with said valve member at an end opposite said first end; a first spring supported by said body member at one end and biasing said valve member in a direction of a closed position thereof; and a second spring supported by said body member at one end and biasing said valve member in a direction of an open position thereof wherein said second spring further comprises a shape memory alloy spring expandable so as to maintain a memorized shape at a predetermined temperature.