JP2004028402A5 - - Google Patents

Description

0006
[Means for solving problems]
In the present invention according to claim 1, in order to achieve the above object, the present invention is a steam compression type refrigerator that transfers heat on the low temperature side to the high temperature side, and is a compressor (10) that compresses a refrigerant. A high-pressure side heat exchanger (20) that dissipates heat from the high-pressure refrigerant, a depressurizing means (40) that depressurizes and expands the high-pressure refrigerant, and a low-pressure side heat exchanger (30) that evaporates the low-pressure refrigerant to absorb heat. The depressurizing means includes a nozzle (41) for equientropically depressurizing and expanding the high-pressure refrigerant, and an ejector (40) having a booster (42, 43) for converting the enthalpy decreased during depressurization and expansion into pressure energy. During the defrosting operation to remove the frost adhering to the surface of the side heat exchanger (30), the throttle opening of the nozzle (41) is increased compared to before the defrosting operation to increase the pressure of the low pressure refrigerant. It is characterized by that.

As a result, the defrosting operation can be performed by a simple means such as increasing the throttle opening of the nozzle (41) , so that the number of parts of the steam compression type refrigerator can be increased, the structure can be complicated, and the assembly man-hours can be increased. Can be prevented. As a result, the manufacturing cost of the steam compression refrigerator can be reduced, and a new steam compression refrigerator different from the conventional one can be obtained.

In the invention according to claim 2, it is provided on the refrigerant suction side of the compressor (10), separates the inflowing refrigerant into a gas phase refrigerant and a liquid phase refrigerant, and sucks the vapor phase refrigerant into the compressor (10). A gas-liquid separator (50) to be supplied to the side is provided, and the refrigerant flowing out of the ejector (40) flows into the gas-liquid separator (50), and further, the gas-liquid separator (40) is pumped by the pumping action of the ejector (40). The refrigerant is supplied from the low pressure side heat exchanger (30) from 50) .

The invention according to claim 3 is characterized in that, in an operation mode other than the defrosting operation, the throttle opening degree of the nozzle (41) is controlled according to a heat load.

The invention according to claim 4 is characterized in that the pressure of the low-pressure refrigerant during the defrosting operation is a pressure at which the saturation temperature of the refrigerant becomes 0 ° C. or higher.

The invention according to claim 5 is characterized in that the pressure of the high-pressure refrigerant is equal to or higher than the critical pressure of the refrigerant.

The invention according to claim 6 is characterized in that carbon dioxide is used as a refrigerant.

Claims (6)

A vapor compression type refrigerator which moves low temperature side heat to high temperature side, which is a compressor (10) for compressing a refrigerant, a high pressure side heat exchanger (20) for radiating heat of a high pressure refrigerant, and a high pressure refrigerant A decompression unit (40) for expansion and decompression, and a low pressure side heat exchanger (30) for evaporating and absorbing the low pressure refrigerant ;
The decompression means is
And an ejector (40) having a nozzle (41) for isoentropically decompressing and expanding high-pressure refrigerant, and a booster (42, 43) for converting enthalpy reduced at the time of decompression and expansion into pressure energy.
The front SL low-pressure side heat exchanger (30) during the defrosting operation for removing frost adhering to the surface of, the throttle opening degree of the nozzle (41), low-pressure refrigerant and larger than that before performing the defrosting operation A vapor compression type refrigerator characterized by raising the pressure of Gas-liquid separation provided on the refrigerant suction side of the compressor (10) to separate the inflowing refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant and supplying the gas-phase refrigerant to the suction side of the compressor (10) Equipped with a container (50),
The refrigerant that has flowed out of the ejector (40) flows into the gas-liquid separator (50), and the low-pressure heat exchanger (30) is further discharged from the gas-liquid separator (50) by the pumping action of the ejector (40). 2. The vapor compression refrigerator according to claim 1, wherein the refrigerant is supplied to the The vapor compression refrigerator according to claim 1 or 2, wherein in the operation mode other than the defrosting operation, the throttle opening degree of the nozzle (41) is controlled according to a heat load. The vapor compression refrigerator according to any one of claims 1 to 3, wherein the pressure of the low pressure refrigerant during the defrosting operation is a pressure at which the saturation temperature of the refrigerant is 0 ° C or higher. The vapor compression refrigerator according to any one of claims 1 to 4, wherein a pressure of the high pressure refrigerant is equal to or higher than a critical pressure of the refrigerant. The vapor compression refrigerator according to any one of claims 1 to 5, wherein carbon dioxide is used as the refrigerant.