PURPOSE: To maintain a refrigerant circulation amount in a refrigerating cycle at a suitable value by connecting a plurality of capillary tubes having different resistance values in parallel with a tube between a condenser and a cooler.
CONSTITUTION: A refrigerant discharge side of a compressor 11 is connected to a refrigerant inlet side of a condenser 12, and a dryer is connected to a refrigerant outlet side of the condenser 12. A refrigerant tube from the dryer is output from a condensing unit 4 into a room and connected to a cooler 7 in a heat insulation box 3 through a passage controller and a pressure reducing unit 18. A tube 19 from the cooler 7 is output from the box 3 out of the room, and connected to a refrigerant suction side of the compressor 11. The unit 18 has a plurality of capillary tubes connected in parallel with a refrigerant tube. A resistance value against a refrigerant flow is largest at the first capillary tube, intermediate at the second capillary tube, and lowest at the third capillary tube. Three solenoid valves of the controller are respectively connected in series with the capillary tubes.
MARU KENJI
YAMAGISHI NOBUYASU
