JPS63187058A - 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 Industrial Application] The present invention relates to a refrigeration system that performs capacity control using a hot gas bypass method, and particularly to a hot gas bypass circuit thereof.

[Conventional technology]

The above-mentioned hot gas bypass method is conventionally known as a method for controlling the capacity of a refrigerator during low load.

Next, FIG. 2 shows a refrigerant circuit of a conventional refrigeration system that employs the capacity control system using the hot gas bypass method described above. In the figure, 1 is a compressor, 2 is a condenser, 3 is an expansion valve,
Reference numeral 4 denotes an evaporator, and a main refrigerant circuit 5 is constructed by connecting these in order with piping. On the other hand, apart from the main refrigerant circuit 5, a condenser 2. A gas bypass circuit 7 is connected directly to the inlet of the evaporator 4 by bypassing the expansion valve 3 and passing through the hot gas bypass valve 6. Note that 8 is an evaporation pressure regulating valve interposed on the suction side of the pressure 1[1.

With this configuration, when the refrigeration load decreases, a part of the gas discharged from the compressor 1 is bypassed to the evaporator 4 via the hot gas bypass circuit 7, and this amount of bypass gas is transferred to the hot gas bypass valve as a constant pressure expansion valve. 6, the capacity of the refrigeration system is controlled, thereby making it possible to match the refrigeration capacity to fluctuations in the refrigeration load and keep the objects to be cooled at a constant temperature.

[Problem that the invention seeks to solve]

However, the above-mentioned refrigeration apparatus has the following problems. That is, when the refrigeration load decreases, the refrigerant is throttled by the evaporation pressure regulating valve 8, and the refrigerant is sucked into the compressor 1 in a superheated state. For this reason, the temperature of the discharged gas from the compressor 1 rises excessively, and the hot gas whose temperature rises excessively due to the capacity control operation described above flows through the hot gas bypass circuit 7 as it is. On the other hand, the constant pressure expansion valve that is normally used as the hot gas bypass valve 6 on the market has little consideration given to heat resistance in its specifications, which causes the hot gas bypass valve 6 to reach excessively high temperatures! ! Problems with reliability remain in long-term use, such as shortening of service life due to exposure.

The purpose of this invention is to solve the heat resistance problem of the hot gas bypass valve and improve its reliability by cooling the temperature of the hot gas flowing through the hot gas bypass circuit and suppressing it to below the allowable value of the hot gas bypass valve. An object of the present invention is to provide a refrigeration device designed to improve the temperature.

[Means for solving problems]

In order to solve the above problems, according to the present invention, a main refrigerant circuit returns from the compressor to the compressor via a condenser, an expansion valve, and an evaporator, and a main refrigerant circuit returns from the compressor to the compressor via a hot gas bypass valve. In a refrigeration system comprising a refrigeration cycle including a hot gas bypass circuit for capacity control leading to an inlet of the hot gas bypass circuit, the temperature of the hot gas flowing through the hot gas bypass valve is adjusted to A radiator shall be installed to cool the gas to a temperature below the allowable value of the gas bypass valve.

[Effect]

With the above configuration, the real gas flowing into the hot gas bypass valve through the hot gas bypass circuit during capacity control operation is cooled by the radiator in the previous stage, and the gas temperature is below the allowable temperature of the hot gas bypass valve as a constant pressure expansion valve. can be suppressed to the value of Therefore, the hot gas bypass valve can sufficiently withstand long-term use in terms of heat resistance, and stable operation is guaranteed.

〔Example〕

FIG. 1 shows a refrigerant circuit diagram of a refrigeration system according to an embodiment of the present invention, and the same parts corresponding to those in FIG. 2 are given the same reference numerals. That is, according to this invention, compression II
A radiator indicated by reference numeral 9 is interposed on the upstream side of the hot gas bypass valve 6 in the hot gas bypass circuit 7 which is piped between the discharge side of the evaporator I and the inlet of the evaporator 4. This radiator 9 is connected to the hot gas bypass circuit 7 during capacity control operation.
It plays the role of cooling the hot gas flowing through it, and is designed to keep the temperature of the hot gas flowing into the hot gas bypass valve 6 below the allowable temperature value of the hot gas bypass valve 6, which is regulated from heat resistance. It is configured as a capacitive heat exchanger.

With this configuration, even in an operating state where the discharge gas temperature of the compressor 1 increases due to a decrease in the refrigeration load, the hot gas flowing through the hot gas bypass circuit 7 is cooled by the radiator 9 by the capacity control operation, and the hot gas The temperature of the gas flowing through the bypass valve 6 is suppressed below the allowable temperature value of the hot gas bypass valve 6 as a constant pressure expansion valve. Therefore, the hot gas bypass valve is heat resistant and can withstand long-term use, ensuring stable operation.

〔Effect of the invention〕

As described above, according to the present invention, the main refrigerant circuit returns from the compressor to the compressor via the condenser, expansion valve, and evaporator, and the main refrigerant circuit returns from the compressor to the inlet of the evaporator via the hot gas bypass valve. In a refrigeration system comprising a refrigeration cycle including a hot gas bypass circuit for capacity control, the temperature of the hot gas flowing through the hot gas bypass valve is determined on the upstream side of the hot gas bypass valve in the hot gas bypass circuit. By installing a heat radiator to cool the product below the allowable value, it solves the problem of heat resistance of the hot gas bypass valve, which was a problem with conventional refrigeration equipment, and enables long-term stable use. Its durability and reliability can be improved.

[Brief explanation of the drawing]

FIG. 1 is a refrigerant circuit diagram of a refrigeration system according to an embodiment of the present invention, and FIG. 2 is a refrigerant circuit diagram of a conventional refrigeration system. In each figure, 1: Compressor, 2: Condenser, 3: Expansion valve, 4: Moisture generator, 5
: Main refrigerant circuit, 6: Hot gas bypass valve, 7: Hot gas bypass circuit, 9: Heat radiator. Figure 1 Figure 2

Claims (1)

[Claims] The main refrigerant circuit returns from the compressor to the compressor via the condenser, expansion valve, and evaporator, and the hot gas bypass circuit for capacity control runs from the compressor discharge side to the evaporator inlet via the hot gas bypass valve. In the refrigeration system having a refrigeration cycle, a radiator is provided upstream of the hot gas bypass valve in the hot gas bypass circuit to cool the temperature of the hot gas flowing through the hot gas bypass valve to a value below the allowable value of the hot gas bypass valve. A refrigeration device characterized in that it is configured with a