THERMAL VALVE AND CONTROL METHOD FOR THE THERMAL VALVE

摘要

PROBLEM TO BE SOLVED: To provide a thermal valve capable of not only controlling a full opening or a full closing but also controlling an intermediate state. SOLUTION: This thermal valve comprises a control valve 3 provided with a plug bar 2 for adjusting a fluid motion; a thermal drive portion 5 for operating the plug bar 2 of the control valve 3 by an output shaft 4; and a control portion 6 for controlling the thermal driving portion 5. The thermal driving portion 5 is provided with a heater 11 and a thermal element 12 for reversibly displacing the output shaft 4 corresponding to a heating degree by the heater 11 and for operating the plug bar 2 through the output shaft 4. The control portion 6 is provided with a displacement quantity detection sensor 13 for detecting a displacement quantity of the output shaft 4 and a control body 14 for controlling a heating degree of the heater 11 based on the displacement quantity of the output shaft 4 detected by the displacement quantity detection sensor 13.