Patent ID: 6405554
Filing Date: 2002-06-18
Classification: F25B,Y02B

Abstract:
A refrigerating system comprising:a high stage side refrigerant circuit (3, 120) formed by connecting a high stage side compressor (9, 18, 121), a condenser (10, 122), a motor-operated expansion valve (12, EVL1, EVL2) and a refrigerant heat exchanger (5, 11A, 111B) in this order; a low stage side refrigerant circuit (2, 103A, 103B) formed by connecting a low stage side compressor (4, 31A, 31B, 131A, 131B), the refrigerant heat exchanger (5, 111A, 111B), an expansion mechanism (7, EV21) and an evaporator (8, 50) in this order; high pressure sensing means (SPH2), provided in the low stage side refrigerant circuit (2, 103A, 103B), for sensing the high pressure in the low stage side refrigerant circuit (2, 103A, 103B); and expansion valve control means (16) for controlling the motor-operated expansion valve (12, EVL1, EVL2) of the high stage side refrigerant circuit (2, 120) so that the pressure sensed by the high pressure sensing means (SPH2) reaches a predetermined:target high pressure.