THERMOSTATIC AUTOMATIC EXPANSION VALVE

PROBLEM TO BE SOLVED: To prevent a sensed temperature from being changed in response to a gaseous phase and a liquid phase of refrigerant by a method wherein a temperature-sensitive cylinder for use in sensing a temperature of refrigerant at an outlet of an evaporator is inserted into and installed at a refrigerant pipe at an outlet of the evaporator. SOLUTION: A temperature-sensitive cylinder 101 is inserted into and fixed to a refrigerant pipe 102 at an outlet of an evaporator. The temperature-sensitive cylinder 101 is inserted into the refrigerant pipe at a female threaded part 102a formed at one end of an inner side of the refrigerant pipe, a capillary tube 105 communicates with it and it is air-tightly pushed and held by a nut 103. A section near the fixing part of the nut 103 is thermally isolated from the surrounding air by a thermal insulator 104. In this way, a thermal giving or acceptance between the surrounding air and the temperature-sensitive cylinder is shut off to cause a temperature of the temperature-sensitive cylinder to be governed only with a temperature of refrigerant flowing around the cylinder and in turn a gaseous phase section of wet refrigerant and a liquid phase section of wet refrigerant flowing in the refrigerant pipe show the same temperature from each other, so that under a state in which no giving or acceptance of heat is provided, a temperature variation of the temperature-sensitive cylinder caused by a difference in coefficients of heat transfer of the gas-liquid refrigerants is not produced.