JPS6140900B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a refrigeration system equipped with a plurality of refrigerant compressors each having an independent refrigerant circuit.
The purpose of this invention is to increase the degree of subcooling of other systems by utilizing exhaust heat during defrosting when each refrigerant circuit is defrosted at predetermined intervals, thereby improving the refrigeration effect.

Conventionally, in refrigeration equipment that uses multiple refrigerant compressors with independent refrigeration circuits, the defrosting operation of each refrigerant circuit is performed independently and without relation to each other, so the waste heat during defrosting is The reality was that it was wasted and not used to improve the freezing effect of other systems.

The present invention has been made in view of the above points, and attempts to utilize exhaust heat by sequentially performing defrosting operations at equal intervals, thereby constantly increasing the degree of subcooling of other systems.

Below, the present invention will be explained with reference to the embodiment shown in the drawings. Reference numerals 1 and 2 are refrigerant compressors, 3 and 4 are condensers, 5,
6 is a pressure reducing valve, 7 and 8 are evaporators, 9 and 10 are accumulators, and 11 and 12 are suction pressure regulating valves, which are connected by piping to form an independent refrigeration cycle, refrigerant circuits 13 of A system and B system. , 14 respectively.

Each refrigerant circuit 13, 14 includes a refrigerant compressor 1,
Three-way valves 15, 16 are provided between the 2 and the condensers 3, 4, and defrosting side pipes 17, 18 are connected between the three-way valves, the pressure reducing valves 5, 6, and the evaporators 7, 8. ing.

Reference numeral 19 denotes a common intermediate heat exchanger, which is connected to the high pressure side refrigerant pipes 20 and 2 of each refrigerant circuit 13 and 14.
1 and a common low pressure side refrigerant pipe 22 during defrosting, and the low pressure side refrigerant pipe 22 is connected to a solenoid valve 2, respectively.
3, 24 and solenoid valves 25, 26 provided in the low pressure side refrigerant pipes 27, 28 during cooling.
It is connected in parallel with 0. 31 is a pressure reducing valve.

Next, in the above circuit configuration, the operation will be explained when the A-system refrigerant circuit 13 including the refrigerant compressor 1 performs the defrosting operation, and the B-system transparent refrigerant circuit 14 including the refrigerant compressor 2 performs the cooling operation. .

First, in the A-system refrigerant circuit 13, the high-temperature refrigerant gas discharged from the refrigerant compressor 1 flows from the three-way valve 15 through the defrosting side pipe 17 as shown by the arrow into the evaporator 7, where it adheres due to the heat of condensation. Thaw any frost that may be present. After that, the low pressure side refrigerant pipe 22 of the intermediate heat exchanger 19
The refrigerant gas is vaporized when passing through the refrigerant compressor 1 via the accumulator 9 and the suction pressure regulating valve 11.

On the other hand, in the B-system refrigerant circuit 14, the high-temperature refrigerant gas discharged from the refrigerant compressor 2 passes through the three-way valve 16 and the intermediate heat exchanger 19, is liquefied in the condenser 4, and then flows into the evaporator 8 from the pressure reducing valve 6, where it flows into the evaporator 8. It vaporizes. Thereafter, it returns to the refrigerant compressor 2 via the electromagnetic valve 30, the accumulator 10, and the suction pressure regulating valve 12.

In the intermediate heat exchanger 19, the low-pressure refrigerant pipe 22 of the A-system refrigerant circuit 13 cools the high-pressure refrigerant pipe 21 of the B-system refrigerant circuit 14, thereby increasing the degree of subcooling. Furthermore, no liquid back-up occurs as a result. During defrosting, the solenoid valve 29 is closed and the solenoid valves 23 and 25 are opened in conjunction with the operation of the three-way valve 15.

Furthermore, although the embodiment describes a two-system refrigeration circuit using two refrigerant compressors, the same applies to a case of three or more systems, and in this case, defrosting is performed sequentially at equal intervals.

As mentioned above, the refrigeration system according to the present invention includes a compressor,
In a refrigeration system configured by combining multiple refrigerant circuits in which a condenser, an expansion device, and an evaporator are sequentially connected via piping, and the outlet side of the compressor and the inlet side of the evaporator are connected by a defrosting side pipe. , one intermediate heat exchanger shared by each circuit is provided on the outlet side of the compressor of each refrigerant circuit, and a side pipe passing through the intermediate heat exchanger is provided on the outlet side of the evaporator of each refrigerant circuit. Each of the refrigerant circuits is configured such that during cooling operation, the refrigerant passes through a compressor, an intermediate heat exchanger, a condenser, an expansion device,
The refrigeration cycle consists of a refrigeration cycle in which the refrigerant flows sequentially through the evaporator, while during defrosting operation, the refrigerant flows in sequence through the compressor, the defrosting side pipe, the evaporator, the side pipe, and the intermediate heat exchanger. Therefore, when defrosting operation and cooling operation are performed in parallel in the plurality of refrigerant circuits, the intermediate heat exchanger connects the high pressure side refrigerant pipe of the refrigerant circuit during cooling operation to that pipe line. Cooling can be carried out in the side pipe of the refrigerant circuit during defrosting operation, through which low-temperature liquid refrigerant flows after defrosting. It is possible to heat the side pipe of the refrigerant circuit during frost operation, increase the degree of subcooling of the refrigerant circuit during cooling operation, improve the freezing effect of the refrigeration system, and reduce liquid backflow after defrosting. .

[Brief explanation of the drawing]

The drawing is a circuit configuration diagram showing an embodiment of the refrigeration system according to the present invention. 1, 2... Refrigerant compressor, 13, 14... Refrigerant circuit, 17, 18... Defrosting side pipe, 19... Intermediate heat exchanger, 20, 21... High pressure side refrigerant pipe, 22...
...Low pressure side refrigerant pipe.

Claims (1)

[Claims] 1 A refrigerant circuit is constructed by combining multiple refrigerant circuits in which the compressor, condenser, expansion device, and evaporator are sequentially connected via piping, and the outlet side of the compressor and the inlet side of the evaporator are connected by a defrosting side pipe. In a refrigeration system, one intermediate heat exchanger shared by each circuit is provided on the outlet side of the compressor of each refrigerant circuit, and the intermediate heat exchanger is provided on the outlet side of the evaporator of each refrigerant circuit. Each of the refrigerant circuits constitutes a refrigeration cycle in which the refrigerant sequentially passes through the compressor, intermediate heat exchanger, condenser, expansion device, and evaporator during cooling operation, while during defrosting operation Sometimes the refrigerant is in the compressor,
A refrigeration system comprising a defrosting cycle that sequentially flows through a defrosting side pipe, an evaporator, a side pipe, and an intermediate heat exchanger.