Refrigerant circuit device

Abstract

A refrigerant circuit device includes: a refrigerant circuit including a condenser installed in the storage room, a compressor absorbing and compressing a refrigerant evaporated in the condenser, a heat radiator causing the refrigerant, compressed by the compressor, to release heat from the refrigerant, an electronic expansion valve causing an adiabatic expansion of the refrigerant which has released heat in the heat radiator, and a refrigerant pipe line sequentially connecting the condenser, the compressor, the heat radiator, and the electronic expansion valve to flow the refrigerant; and a controller, in case of performing a forced cooling operation in which the product stored in the storage room is forcedly cooled, adjusting an opening of the electronic expansion valve in a manner that a temperature or a pressure of the refrigerant that has been discharged from the compressor approaches a predetermined target discharge temperature or a predetermined target discharge pressure, respectively.

What is claimed is: 
     
         1 . A refrigerant circuit device to cool a product stored in a storage room, the refrigerant circuit device comprising:
 a refrigerant circuit including
 a condenser installed in the storage room, 
 a compressor configured to absorb and compress a refrigerant which has been evaporated in the condenser, 
 a heat radiator configured to cause the refrigerant, which has been compressed by the compressor, to release heat from the refrigerant, 
 an electronic expansion valve configured to cause an adiabatic expansion of the refrigerant which has released heat in the heat radiator, 
 a refrigerant pipe line sequentially connecting the condenser, the compressor, the heat radiator, and the electronic expansion valve to flow the refrigerant; and 
   a controller configured to, in case of performing a forced cooling operation in which the product stored in the storage room is forcedly cooled, adjust an opening of the electronic expansion valve in a manner that a temperature or a pressure of the refrigerant that has been discharged from the compressor approaches a predetermined target discharge temperature or a predetermined target discharge pressure, respectively.   
     
     
         2 . The refrigerant circuit device according to  claim 1 , wherein, the controller is configured to, in a case of performing a normal cooling operation in which the product stored in the storage room is cooled to have temperature thereof maintained within a cooling temperature range set in advance, control the opening of the electronic expansion valve in a manner that a temperature of the refrigerant that flows into the condenser approaches a predetermined target evaporating temperature. 
     
     
         3 . The refrigerant circuit device according to  claim 2 , wherein, the controller is configured to, when an internal temperature of the storage room is equal to or lower than a temperature for switching which is lower than a lower limit temperature of the cooling temperature range, switch from the forced cooling operation to the normal cooling operation. 
     
     
         4 . The refrigerant circuit device according to  claim 3 , wherein the temperature for switching is set in a manner that the product in the storage room has temperature to be equal to or lower than an upper limit temperature of the cooling temperature range. 
     
     
         5 . The refrigerant circuit device according to  claim 1 , wherein carbon dioxide is used as the refrigerant.