| 摘要 |
A high-pressure side discharge port of a two-stage compressor ( 12 A) and a condenser ( 14 A) are connected, condenser ( 14 A) and a PMV ( 15 A) are connected, a refrigerating side exit of PMV ( 15 A) is connected to a medium pressure side suction port of two-stage compressor ( 12 A) via an R capillary tube ( 16 A) and an F evaporator ( 18 A), connected to an F evaporator ( 26 A) via an F capillary tube ( 24 A), F evaporator ( 26 A) is connected to a low-pressure side suction port of two-stage compressor ( 12 A) via a low-pressure suction pipe ( 28 A), PMV ( 15 A) can switch a simultaneous cooling mode and a freezing mode, and in the simultaneous cooling mode, a refrigerant flow rate toward R evaporator ( 18 A) is adjusted by PMV ( 15 A), and thereby a temperature difference control is performed so as to make a difference between an entrance temperature and an exit temperature of R evaporator ( 18 A) equal to a preset temperature difference (for example, 4° C.). A controller ( 22 ), on the basis of the detection condition of a temperature sensor ( 23 ) for a freezing chamber and a temperature sensor ( 24 ) for a refrigerating chamber, controls a freezing cycle device ( 10 ). Here, controller ( 22 ) controls an opening of a regulating valve ( 12 ) so as to make a superheat amount which is a difference between an exit temperature and an entrance temperature of a refrigerating evaporator ( 5 ) equal to a target superheat amount, and thereby adjusts a refrigerant flow rate to refrigerating evaporator ( 5 ) in a limited state. In this case, when a power is turned on, the entrance temperature and the exit temperature of refrigerating evaporator ( 5 ) are the same, so that controller ( 22 ), when the power is turned on, calibrates detected temperatures of an entrance temperature sensor ( 27 ) and an exit temperature sensor ( 26 ) so as to coincide with each other, and thereby can execute surely the subsequent limiting adjustment of regulating valve ( 12 ) on the basis of the superheat amount. Further, in this case, when a refrigerant supply to refrigerating evaporator ( 5 ) is stopped and the temperature of refrigerating evaporator ( 5 ) rises suddenly, controller 22 increases an opening of a valve opening ( 42 ) to refrigerating evaporator ( 5 ) of regulating valve ( 12 ) to a predetermined return value, so that the refrigerant supply amount to refrigerating evaporator ( 5 ) is increased at a stretch, and thus the refrigerating evaporator can be cooled quickly. A refrigerator having a two-stage compressor ( 12 A) for cooling efficiently both a refrigerating chamber ( 2 A) and a freezing chamber ( 5 A) will be provided. When limiting and adjusting a refrigerant flow rate to one evaporator according to an opening of a valve body so as to make a superheat amount of one evaporator appropriate on the basis of the superheat amount which is a difference between an exit temperature and an entrance temperature of one evaporator, a refrigerator for detecting accurately the entrance temperature and the exit temperature of one evaporator will be provided. When limiting and adjusting a refrigerant flow rate to one evaporator according to an opening of a valve body, a refrigerator for causing no delay in a refrigerant supply to one evaporator will be provided.
|
