JPS6045342B2 - Refrigeration equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a refrigeration system that can greatly increase the amount of heat required for defrosting compared to conventional systems, and can also simplify the refrigerant piping system.

Therefore, the device of the present invention has a plurality of compressors IA and IB having the same suction pressure, and a separate compressor 1 having a different suction pressure from these compressors, that is, the suction pressure is lower than that of the compressors IA and IB. Each discharge side 2a, 2b, 2 is commonly connected 3 in parallel to one condenser 4, and this condenser 4 is connected 7 to one liquid receiver 6, and a liquid sending pipe 8 from the liquid receiver is connected. , each expansion valve 10a, 1
Coolers 11A, 11B, 1 with branch pipes equipped with 0b, 10
1, and the refrigerant return pipes 12a and 12b of the coolers 11A and 11B with the same pressure are connected to the suction lo of the compressors IA and IB with the same suction pressure via one suction header 13,
15a, 15b, but the return pipe 12 of the remaining cooler 11 is connected 15 to the suction port of the different suction pressure compressor 1 without going through a suction header, and the liquid receiver 6 is connected to the suction pipe 15 to send the gas therein. A trachea 17 connects to the gas intermediate reservoir 16, and a return pipe 12a from each cooler is connected to the gas intermediate reservoir 16.
12b, 12 are connected to branch connections 19a, 19b, 12 through flow path switching valve devices such as three-way valves 18a, 18b, 18, etc.
It is said to have a structure of 19.

Here, in addition to the illustrated three-way valve, the flow path switching valve device includes:
In some cases, the structure is such that one switching valve is provided in each of the return pipe and the branch pipe.

In addition, the liquid receiver 6 may also be used as a condenser, and the return pipe 12 of the cooling pipe 11 may be connected to the suction header 1 or 3 by a branch pipe 21 equipped with a protective check valve 20. There is also. Note that 22, 22a, and 22b are defrost bypass valves, and 23, 23a, and 23b are bypass pipes thereof. In the above-mentioned apparatus of the present invention, the return refrigerant from the cooler during refrigeration operation is transferred from the coolers 11A, 1 and IB to the suction header 13, suction pipes 14, 15a,
15b to the compressors IA and IB, and the cooler 11
The air is sucked into the compressor 1 from the suction pipe 15 without passing through the suction header.

By the way, each refrigerant return pipe is connected to a switching valve 18 to an intermediate gas reservoir 16 into which saturated refrigerant gas from the liquid receiver 6 is sent.
Since the trachea 19a, 19b, and 19 are connected through the trachea 19a, 18b, and 18, the illustrated three-way switching valve is
By rotating the pipes 12a, 12b, 12 by 30 degrees, the saturated gas in the intermediate gas reservoir 16 is returned to the respective coolers.
You can defrost each cooler by reversing the flow with
The figure shows the cooler 11 during defrosting. In addition, hot gas instead of saturated gas may be used as the defrosting gas, and in this case, it may be necessary to
is connected to the intermediate gas reservoir 16 through a trachea 17. As described above, according to the present invention, the hot gas from the compressor and the saturated gas from the liquid receiver are pooled in the intermediate gas reservoir. Defrosting can be easily carried out by sending hot gas or saturated gas into the cooler, and not only can sufficient heat be stored for defrosting, but the defrosting piping system can also be simplified. It also has the advantage of reducing equipment costs.

Furthermore, in addition to the compressors 1A and 1B with the same suction pressure, a compressor 1 with a lower suction pressure is provided, and the refrigerant return pipe 12 from the cooler 1 is connected to the suction header 1 in the compressor 1.
Since the compressors 15 are connected without going through 3, even if the loads of multiple coolers are different or partially different, it is necessary to use compressors 1, 1A, and 1B that can handle the maximum load. Instead, only the compressor 1 needs to be set for maximum load, and the horsepower of the entire compressor can be reduced, saving electric power and saving energy.

[Brief explanation of the drawing]

The figure is a circuit diagram showing an example of a device according to the present invention. In the diagram, 1, 1A, 1B... Compressor, 4...
...Compressor, 6...Liquid receiver, 11, 11A, 1
1B...Cooler, 13...Suction header, 16...Gas intermediate reservoir, 18, 18a,
18b...Flow path switching device, 19, 19a, 19
b...Trachea.

Claims (1)

[Claims] 1 The discharge sides of multiple compressors with the same suction pressure and separate compressors with different suction pressures are commonly connected in parallel to a condenser, and this condenser is connected to a liquid receiver. Then, the liquid sending pipe from the liquid receiver is connected to each cooler by a branch pipe each equipped with an expansion valve, and each refrigerant return pipe of the cooler with the same pressure is connected to the same suction pipe through one suction header. The return pipe of the remaining cooler is connected to the suction port of the compressor with a different suction pressure without going through a suction header, and the liquid receiver is connected therein. The trachea connects the gas intermediate reservoir to the gas intermediate reservoir, and the return pipes from each cooler are branched to this gas intermediate reservoir via a three-way flow switching valve device such as a three-way valve. Refrigeration equipment.