VARIABLE EJECTOR TYPE REFRIGERATING CYCLE AND HEAT PUMP TYPE WATER HEATER

摘要

PROBLEM TO BE SOLVED: To prevent the biting of a needle valve into a nozzle in fully-closing motion at restarting.;SOLUTION: In this variable ejector type refrigerating cycle, a heat pump ECU 20A stops a compressor 1, and controls a nozzle of an ejector 3 to be opened to a prescribed value when an operation of a refrigerating cycle is stopped. A probability of biting the needle valve 3f into the nozzle 3a exists only when a fully-closing position of the needle valve 3f is confirmed in a state that a pressure difference exists at restarting. The pressure difference in the refrigerating cycle is quickly eliminated by opening the nozzle to a prescribed value when the refrigerating cycle is stopped. Thereby a taper formed on the needle valve 3f for preventing the biting becomes unnecessary, cost can be reduced while improving control performance in an extremely low flow rate, and the biting of the needle valve 3f into the nozzle 3a in a fully-closing operation at restarting can be prevented.;COPYRIGHT: (C)2007,JPO&INPIT