JPS5924148A - 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 The present invention relates to a refrigeration cycle of a refrigerator and a method of controlling the same, and particularly to a method for preventing hot gas in an evaporator from flowing into a condenser or compressor during defrosting, and furthermore, The present invention relates to a refrigerator that allows easy startup of a compressor after defrosting.

A conventional refrigeration cycle will be explained with reference to FIG. 1. A compressor 1, a condenser 2, a pressure reducer 3, and an evaporator 4 are successively connected through refrigerant pipes. A defrosting heater is installed in the evaporator 4, and during defrosting, the compressor 1 is stopped and the defrosting heater is energized to melt the frost using electrical energy. In the above-mentioned refrigeration cycle that performs defrosting, the gas refrigerant heated by the defrost heater passes through the refrigerant pipe from the evaporator 4 and flows into the compressor 1 or condenser 2, so it must be heated before the defrosting is completed. The drawback was that it generated a lot of heat.

An object of the present invention is to provide a refrigerator that reduces power consumption and heat load of a defrost heater during defrosting, and facilitates starting of a compressor after defrosting.

In the conventional defrosting method using a refrigeration cycle, the gas refrigerant heated by the defrost heater flows from the evaporator to the compressor or condenser, so the temperature of the evaporator rises slowly and the heating time of the defrost heater becomes longer. Put it away. As a result, it was not possible to reduce power consumption during defrosting. Therefore, the present invention focuses on reducing the power consumption of the refrigeration cycle by providing on-off valves upstream and downstream of the evaporator and controlling the refrigerant in the evaporator so that it does not move during defrosting.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3. 6.7 in FIG. 2 is an on-off valve, which prevents the gas refrigerant generated in the evaporator from flowing into the compressor and condenser during defrosting operation, thereby shortening the defrosting time. 5 is a defrosting heater. During defrosting, the on-off valve 6 is closed as soon as the compressor is stopped, as shown in FIG. 3, and the defrost heater 5 installed in the evaporator is energized to heat the evaporator and defrost it.

During this defrosting period, the refrigerant remaining in the evaporator is heated and its temperature rises, but unlike conventional methods, it does not flow into the compressor or condenser, so the evaporator and refrigerant remaining in the evaporator are heated. The power consumption of the defrosting heater is small. As a result, the heat load on the evaporator side can be reduced. Further, when starting the compressor after defrosting is completed as shown in A of FIG. 3, a control method is used in which the compressor is started after a certain period of time, for example, 3 to 10 minutes, as shown in B. According to control B, the pressure of the refrigeration cycle after defrosting is balanced, so that the compressor can be started easily. By opening the valve 6 for 7 hours under control B, the pressure balance can be achieved more quickly. Therefore, the refrigeration cycle of the present invention has the effect of being able to reduce the amount of power consumed during defrosting, and making it easier to start up the compressor after defrosting.

Furthermore, when an instantaneous energization valve is used as the opening/closing valve, it is sufficient to energize the valve at the moment of opening/closing operation, which has the advantage of reducing the amount of power consumed by the valve.

In the above description, the on-off valve has been explained, but specifically, there are electromagnetic on-off valves, pressure-type on-off valves, temperature-type on-off valves, etc., which can exhibit similar effects.

Present invention 3. According to the above, an on-off valve is provided between the condenser and the pressure reducer, and between the evaporator and the compressor, and the on-off valve is controlled to be closed when the defrost heater is energized, so the power consumption of the defrost heater can be reduced. At the same time, the heat load caused by the defrosting heater on the evaporator side can be reduced. Further, by delaying the start-up of the compressor after defrosting, the pressure of the refrigeration cycle is balanced, so that the start-up of the compressor can be facilitated.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a refrigeration cycle of a conventional refrigerator, FIG. 2 is a block diagram of a refrigeration cycle of a refrigerator according to the present invention, and FIG. 3 is a diagram of a defrosting heater, an on-off valve, and a compressor of a refrigerator according to the present invention. FIG. 2 is a diagram showing a control pattern of FIG. 1... Compressor, 2... Condenser, 3... Pressure reducer, 4
...Evaporator, 5.Defrost heater, 6.7.Opening/closing valve. </'' 2゜茅1c21

Claims (1)

[Claims] 1. In a refrigeration cycle in which a compressor, a condenser, a pressure reducer, and an evaporator are sequentially connected through a refrigerant pipe, an on-off valve is provided between the condenser and the pressure reducer and between the evaporator and the compressor. What is claimed is: 1. A refrigerating machine characterized in that the on-off valve is controlled to close during defrosting operation. 2. The refrigerator according to claim 1, wherein an on-off valve is installed only between the condenser and the pressure reducer, and is controlled to close during defrosting operation. 3. The refrigerator according to claims 1 and 2, wherein the compressor is started after a certain period of time after defrosting. 4. The refrigerator according to claim 1, wherein the valve (6) is opened for a certain period of time (τ,) after defrosting. 5. The refrigerator according to claim 1, characterized in that an instantaneous energization valve is used as the on-off valve.