Refrigeration cycle device

Abstract

A mixed refrigerant including a plurality of component refrigerants circulates in a refrigeration cycle device. An expansion valve includes a power element. A filled fluid filled in the power element is one component refrigerant in the plurality of component refrigerants. A slope of a saturated vapor pressure curve of the filled fluid is larger than the slope of the saturated vapor pressure curve SV 0 of the mixed refrigerant. Thereby, an opening degree of the expansion valve can be prevented from exceeding in a low-temperature region, and the opening degree corresponding to a load can be obtained in a high-temperature region.

1 . A refrigeration cycle device comprising:
 a refrigerant cycle including a compressor, a condenser, an expansion valve and an evaporator, which are coupled in this order; and   a mixed refrigerant made of a plurality of component refrigerants, which is circulated in the refrigerant cycle, wherein   the expansion valve includes:
 a valve portion configured to adjust an amount of the mixed refrigerant supplied into the evaporator based on an opening degree of the valve portion; and 
 a power element configured to adjust the opening degree of the valve portion based on a pressure of a filled fluid that is filled inside the power element, and 
   a slope of a saturated vapor pressure curve of the filled fluid is larger than a slope of a saturated vapor pressure curve of the mixed refrigerant.   
   
   
       2 . The refrigeration cycle device according to  claim 1 , wherein
 the filled fluid is one component refrigerant of the plurality of component refrigerants, and   a slope of a saturated vapor pressure curve of the one component refrigerant is larger than the slope of the saturated vapor pressure curve of the mixed refrigerant.   
   
   
       3 . The refrigeration cycle device according to  claim 2 , wherein
 the slope of the saturated vapor pressure curve of the one component refrigerant is the largest in the plurality of component refrigerants.   
   
   
       4 . The refrigeration cycle device according to  claim 1 , wherein
 a slope of a saturated vapor pressure curve of one component refrigerant is the smallest in the plurality of component refrigerants, and   the filled fluid is made of at least one of the plurality of component refrigerants other than the one component refrigerant.   
   
   
       5 . The refrigeration cycle device according to  claim 1 , wherein
 the filled fluid is one component refrigerant in the plurality of component refrigerants.   
   
   
       6 . The refrigeration cycle device according to  claim 1 , wherein
 the slope of the saturated vapor pressure curve of the filled fluid is larger than the slope of the saturated vapor pressure curve of the mixed refrigerant in a general range from a low-temperature region to a high-temperature region.   
   
   
       7 . The refrigeration cycle device according to  claim 1 , wherein
 a saturated vapor pressure difference between the saturated vapor pressure curve of the filled fluid and the saturated vapor pressure curve of the mixed refrigerant gradually increases as an evaporation temperature increases.