| 摘要 |
PURPOSE:To make a valve small-sized and eliminate vibration sounds by allowing a valve body to close a path invariably with a spring and providing a seal member on an operation bar to seal the path. CONSTITUTION:When the temperature of an evaporator outlet 12 is increased, the temperature of the evaporator outlet is conveyed to a temperature sensing element 15 through a capillary 20, and since the high-pressure refrigerant in the first fluid passage 11 is cut off by a seal member 29, the pressure of a chamber 19 is made equal to that on the evaporator side through an equalizer path 21, the pressure of a chamber 18 is made higher than that of the chamber 18 and a diaphragm 17 is displaced downward, thus displacing an operation bar 22 likewise downward. Therefore, a valve body 24 is displaced in the same direction against the flexibility of a spring 27 and is moved apart from a valve seat 28. Accordingly, the high-pressure and high-temperature refrigerant in the first fluid passage 11 is adiabatically expanded through the valve seat and the second fluid passage 14 to attain a low pressure and a low temperature, then it reaches an evaporator to perform a predetermined temperature control. When the outlet temperature of the evaporator is decreased, the pressure of the chamber 18 of the temperature sensing element is made lower than that of the chamber 19, and the valve body 24 is closed, the high-pressure and high-temperature refrigerant in the first fluid passage 11 is cut off and is not guided into the evaporator, thus the inside of the evaporator is controlled at a desired temperature. |
