JPS60178259A - Two-element refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a binary refrigeration system, and more particularly to a structure for preventing overload during startup of a low-temperature side refrigeration cycle.

[Background of the Invention] FIG. 1 shows a cycle diagram of a conventional dual refrigeration system. ^ Temperature 1111.1 refrigeration cycle is pan temperature side compression P
A1, curdler 2, expansion valve 3, cascade condenser +j4
It's getting better. The sweet cold-blooded low-temperature cycle consists of the low-temperature side compressor 5, the cascade condenser 4, the expansion valve b1, and the evaporator r. Then, in the high temperature side cold expansion cycle, the refrigerant discharged from the still temperature side compressor 1 is liquefied in the condenser 2 and 1. The pressure is reduced by the expansion valve 3, the cascade condenser 4 exchanges heat with the refrigerant of the low temperature side refrigeration cycle, evaporates, and returns to the high temperature side compressor 1 again. On the other hand, the low temperature side refrigeration cycle V
In C, 2 tons of refrigerant discharged from the low temperature side compressor 5 is condensed and liquefied in the cascade condenser 4, oils the expansion valve 6, exchanges heat with the object to be cooled in the evaporator 7, and returns to the low temperature N machine 5
Return to

In this binary refrigeration system, the refrigerants (R-13, R-03, etc.) used in the low-temperature side refrigeration cycle generally have low saturated vapor pressures, so an expansion tank 8 and a capillary tube 9 are installed in the low-pressure side path. When the operation is stopped, the refrigerant is stored in the expansion tank 8 to keep the pressure in the refrigeration cycle low. Then, at the start of operation, the expansion tank 8
The refrigerant inside is gradually returned to the refrigeration cycle through the capillary tube 9' to prevent overload operation of the low temperature side compressor 5.

However, since the refrigerant is stored in the expansion tank 8 through the entire capillary tube 9, the refrigerant does not easily enter the expansion tank 8 immediately after the operation is stopped, and the pressure of the refrigeration cycle is not reduced. Since the function of 8 cannot be fully demonstrated, there is a problem that the amount of refrigerant circulated increases when restarting immediately after stopping, resulting in overload operation of the low-pressure side compressor 5.

[Purpose of the invention]

OBJECTS OF THE INVENTION 1. It is an object of the present invention to provide a dual refrigeration system that allows the function of an expansion tank to be fully exhibited even immediately after the operation of the refrigeration cycle is stopped, and that can prevent overload operation of the low-temperature side compressor.

(Summary of the invention) The present invention provides a check valve in parallel to a capillary tube,
Immediately after the operation of the refrigeration cycle is stopped, the refrigerant is quickly recovered into the expansion tank through the check valve, and after the operation is started, the refrigerant is recovered to V'.
It is characterized in that the refrigerant in the expansion tank is gradually returned to the refrigeration cycle through a capillary tube.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. FIG. 2 shows a cycle system diagram of the dual refrigeration system according to the present invention, and the same reference numerals as in FIG. 1 represent the same or equivalent components. This binary refrigeration system is provided with a reverse valve 10 connected in parallel to a capillary tube 9. The check valve 10 is configured to allow the refrigerant to flow only toward the expansion tank 8 side.

In the above-mentioned binary refrigeration system, when the low temperature side compressor 5 stops, the refrigerant in the refrigeration cycle quickly flows into the expansion tank 8 through the check valve IUt, and the pressure in the refrigeration cycle is reduced in a short time. decreases, so even if the compressor 5 is restarted immediately after being stopped, the low-temperature side compressor 5 will not go into overload operation. Further, after the low temperature side compressor 5 is started, the refrigerant in the expansion tank 8 is gradually returned to the refrigeration cycle through the capillary tube 9, so that the normal cooling operation is performed without overload operation.

〔Effect of the invention〕

As explained above, according to the present invention, the function of the expansion tank can be fully exhibited at all times, so that overload operation of the low-temperature side compressor can be prevented even when restarting immediately after stopping.

[Brief explanation of drawings]

FIG. 1 is a cycle system diagram of a conventional binary refrigeration system, and FIG. 2 is a cycle system diagram of a dual system refrigeration system according to the present invention. 5...low temperature side compressor, 8...expansion unit, 9...
Capillary tube, 10... check valve. Representative patent attorney Akio Takahashi 11 ≠ zfJ

Claims (1)

[Claims] High temperature side compressor, condenser, expansion valve, stop side refrigeration cycle such as cascade condenser, low temperature side compressor, front DC
A binary refrigeration system K is equipped with a low-temperature side refrigeration cycle consisting of a cascade condenser, an expansion valve, and an evaporator, and an expansion tank is connected to the low-pressure side thread path of the low-temperature side refrigeration cycle via a capillary tube. A two-way refrigeration system characterized in that a check valve that allows the flow to flow only toward the expansion tank is provided in parallel with the capillary tube.