JP2000274840A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a fault due to a liquid refrigerant specially when restarted by sensing a liquefying ratio of the refrigerant sucked into a compressor, stopping the compressor when the ratio becomes a given value or above, operating a heating means, and controlling so that the compressor becomes a given temperature. SOLUTION: When the refrigerator is operated, a refrigerant is compressed by a compressor 1 to become high temperature and high pressure gas. The gas flows to a condenser 3 where the gas is cooled and condensed to become a high pressure liquid, which is pressure reduced by a pressure reducing unit 4, and then fed to an evaporator 5. Here, the liquid refrigerant derives circumferential heat to be evaporated and becomes a gaseous state to be sucked to the compressor 1. In this case, if a wet vapor suction for sucking a large amount of the liquid refrigerant to the compressor 1 due to a certain cause occurs, a liquefying ratio of the refrigerant is sensed by a sensing means 8. Then, if the vapor suction for causing a damage of the compressor 1 is decided by a deciding means 9, a constraint voltage is given to a motor 1a of the compressor 1 to heat the compressor by a reactive power while stopping the compressor 1, thereby expediting vaporization of the liquid refrigerant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator for heating and circulating a liquid refrigerant returned to a compressor.

[0002]

2. Description of the Related Art FIG. 7 is a block diagram showing the structure of a conventional refrigerator disclosed in Japanese Patent Application Laid-Open No. 8-226714. FIG. 8 is a schematic diagram and a timing chart of the motor windings in the open-phase current state of the compressor motor of the refrigerator.

In FIG. 7, 29 is a compressor, 30 is a compressor of the compressor 29, 30a is a revolving scroll of the compressor 30, 30b is a fixed scroll of the compressor 30, 31 is a suction pipe, 32 Is a discharge pipe, 33 is a compressor 2
9 is a motor for driving the compressor 9, 34 is a compressor power supply circuit, 35 is a controller, and 36 is a flow switch or the like provided in the suction pipe line 31. When the refrigerant liquid amount in the compressor 29 exceeds a set amount, This is a refrigerant liquid amount detection unit that outputs an output signal.

In FIG. 8, (a) shows a motor 3
3 shows the relationship between the winding No. 3 and the current flowing through the winding. As shown in this figure, the current I and the current I ′ are alternately flown only in the U and V phases with the W phase being open. FIG. 3B is a timing chart showing the current supply state.

Next, the operation in this configuration will be described. First, the control device 35 checks the output from the refrigerant liquid amount detecting means 36 while the compressor 29 is stopped, and determines whether or not the output is continuous for a predetermined time or more. Next, when it is determined that the output from the refrigerant liquid amount detecting means 36 has continued for a predetermined time or more as a result of this determination, the control device 35 applies a weak voltage as shown in FIG. Since the compressor power supply circuit 34 is controlled so that a high-frequency loss current flows, the temperature of the windings of the motor 33 rises and becomes warm by this control, whereby the refrigerant laid in the lubricating oil of the compressor 29 is warmed. Since the gas is gasified and exits from the lubricating oil, the liquid level of the refrigerant buried in the lubricating oil decreases. Next, the reduced refrigerant liquid level is detected by the refrigerant liquid amount detecting means 3.
6 and outputs it to the control device 35.
5 drives the compressor 29.

Japanese Patent Application Laid-Open No. Sho 59-113284 discloses a technique in which a compressor is started by applying a low frequency or a DC power supply voltage for a certain period of time so that the compressor does not rotate when the compressor is started, and then increasing the power supply frequency. It has been disclosed.

[0007]

As described above,
In the conventional refrigerator, although the compressor is protected from oil compression generated due to the refrigerant stagnated in the compressor lubricating oil before operation, the compressor is operated by a liquid refrigerant returning to the operating compressor, a so-called liquid bag. However, there was a problem that the device was damaged.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is possible to avoid damage to a compressor caused by liquid back of a predetermined value or more during operation,
An object of the present invention is to provide a highly reliable refrigerator that operates by gasifying a refrigerant liquid that has been backed up.

[0009]

According to the present invention, there is provided a refrigerator in which a compressor having a heating means, a condenser, a decompressor, and an evaporator are sequentially connected by piping, and the refrigerant is sucked into the compressor. Liquid-liquid ratio detecting means for detecting the liquid ratio of the refrigerant, based on the detection result of the liquid ratio detecting means,
Control means for stopping the compressor when the liquid ratio of the refrigerant is equal to or more than a predetermined value, and operating the heating means to control the temperature of the compressor to a predetermined temperature. It is a thing.

The heating means comprises an electric motor incorporated in the compressor, and the control means supplies a constrained voltage to the electric motor to stop the compressor, and the temperature of the compressor is reduced to a predetermined temperature. Control to be

The heating means is attached to the compressor and comprises an electric heater for heating lubricating oil of the compressor. The electric heater is operated by the control means so that the temperature of the compressor becomes a predetermined temperature. It is controlled so that

Further, the control means operates the defrost heater attached to the evaporator when the control means operates the heating means so that the temperature of the compressor becomes a predetermined temperature.

Further, the control means drives the blower of the evaporator when the control means controls the temperature of the compressor to a predetermined temperature by operating the heating means.

Further, when the control means operates the heating means so that the temperature of the compressor becomes a predetermined temperature, the pressure reducing device prevents the refrigerant of the condenser from flowing to the evaporator. Is to close.

An accumulator is provided between the evaporator and the compressor, and separates the refrigerant into a liquid refrigerant and a gas refrigerant, and is provided in parallel with a refrigerant pipe connecting the accumulator and the compressor. An oil return pipe connecting the bottom of the accumulator and the oil reservoir of the compressor and returning the lubricating oil at the bottom to the oil reservoir by a head difference;
A control valve provided in the oil return pipe to regulate the flow of the lubricating oil, wherein the control means opens the control valve when controlling the temperature of the compressor to a predetermined temperature. Things.

Further, the control means drives the compressor when the temperature of the compressor reaches a predetermined temperature.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a configuration diagram of a refrigerator according to Embodiment 1 of the present invention. In addition,
The solid line in this figure shows the flow in the refrigerant system, and the dotted line shows the flow in the electric system.

In FIG. 1, reference numeral 1 denotes a compressor for sucking and compressing a refrigerant, and reference numeral 2 denotes a compressor power supply for driving the compressor 1. The compressor 1 includes a compressor motor 1a which is an electric motor driven by a compressor power supply device 2, a compressor 1b driven by the compressor motor 1a to compress a refrigerant, and an outer shell of the entire compressor. A compressor shell 1c;
It is composed of 3 is a condenser for cooling the refrigerant discharged from the compressor 1, 4 is a decompressor such as an expansion valve and a capillary tube for decompressing the condensed refrigerant cooled by the condenser 3, and 5 is a decompressor 4 An evaporator that evaporates the refrigerant by exchanging heat between the depressurized refrigerant and air or the like in the freezer. The compressor 1, the condenser 3, the decompressor 4, and the evaporator 5 are sequentially connected by piping. , A refrigerant circuit is configured.

Reference numeral 7 denotes a refrigerant liquid ratio detector which is provided in a suction refrigerant passage 6 between the evaporator 5 and the compressor 1 and detects the degree of wetness of the refrigerant flowing through the suction refrigerant passage 6 (liquid ratio of the refrigerant). Means 8 are attached to the shell 1c of the compressor and the like, and compressor temperature detecting means 9 for detecting the temperature of the compressor, and 9 is the presence or absence of a liquid bag based on the detection result of the refrigerant liquid ratio detecting means 8, that is, the detected refrigerant. Judging means 10 for judging whether the liquid ratio is equal to or more than a predetermined value, based on the judgment result of this judging means 9, when the liquid ratio of the refrigerant becomes equal to or more than the predetermined value, stop the compressor and operate the heating means. This is control means for controlling the compressor so that the temperature of the compressor becomes a predetermined temperature, that is, the liquid refrigerant is vaporized.

The heating means referred to here is an electric motor 1a built in the compressor, a crankcase heater attached to warm the lubricating oil of the compressor, or a separately provided heater (electric heater). However, in the following description, the electric motor 1 incorporated in the compressor will be described.
a will be described as a representative example.

Next, the operation of the refrigerator of FIG. 1 will be described. First, when the refrigerator is operated, the refrigerant is compressed by the compressor 1, flows as a high-temperature and high-pressure gas to the condenser 3, where it is condensed, becomes a high-pressure liquid, and is decompressed by the decompressor 4, and , And flows into the evaporator 5, where the liquid refrigerant evaporates, becomes a gas state, is sucked into the compressor 1, and repeats the same operation again. In this operating state, the refrigerant sucked into the compressor 1 is always in a gas state, that is, only a refrigerant having a wetness of 0 (dryness of 1) is sucked. Since the signal in which the liquid ratio is equal to or less than the predetermined value is transmitted to the determination unit 9, the determination unit 9 determines that there is no liquid back, that is, it is equal to or less than the predetermined value.
In order to transmit the determination result to the control means 10, the control means 10 continues the operation of the compressor 1.

However, due to sudden changes in the cooling load and operating conditions, etc., the adjustment of the refrigerant flow rate in the decompressor did not work well.
If all liquid refrigerant cannot be gasified at
At the time of so-called liquid back in which a large amount of liquid refrigerant passes through the suction pipe 6 and is sucked into the compressor 1, the liquid ratio of the refrigerant in the liquid back state is detected by the refrigerant liquid ratio detecting means 8 and transmitted to the discriminating means 9. Therefore, the determination means 9 determines whether or not the liquid back causes the compressor 1 to be damaged, that is, whether or not the detection result is equal to or less than a predetermined value, and transmits the determination result to the control means 10.

Next, when the transmitted determination result is equal to or less than the predetermined value, it is determined that the liquid is not back enough to damage the compressor 1, and the control means 10 continues the operation of the compressor 1. However, when the pressure is equal to or more than the predetermined value, the control means 10 stops the operation of the compressor 1 and simultaneously operates the compressor 1 as a heating means.
While the compressor 1 is stopped by supplying the constrained voltage to the motor 1a, the compressor 1 is warmed by the reactive power. In other words, a weak current that does not start the compressor motor 1a flows through the motor 1a, and the compressor 1 is warmed by the heat generated by the winding due to this current, and the liquid refrigerant that has been backed up is vaporized.

When the compressor 1 warms up to a predetermined temperature and gasifies the liquid refrigerant sucked into the compressor by this operation, the compressor temperature detecting means 8 attached to the compressor 1 Since it is detected from the detection temperature that the liquid refrigerant has gasified, and the detection result is transmitted to the control means 10,
The control means 10 releases the constraint voltage supplied to the motor, that is, releases the power supply to the electric heater, and supplies the normal operating voltage to drive the compressor 1. Accordingly, the compressor 1 compresses the gasified refrigerant.

As described above, the liquid ratio of the refrigerant sucked into the compressor is detected by the refrigerant liquid ratio detecting means. Based on the detection result, when the liquid ratio of the refrigerant becomes a predetermined value or more, the control is performed. Since the means stops the compressor and operates the heating means to control the temperature of the compressor to a predetermined temperature, it is possible to avoid damage to the compressor caused by the liquid back exceeding a predetermined value. At the same time, the liquid refrigerant sucked into the compressor is gasified, so that a highly reliable refrigerator that prevents troubles caused by the liquid refrigerant during operation and re-operation can be obtained.

At this time, if the electric motor incorporated in the compressor is used as the heating means, the control means only supplies the constrained voltage to the electric motor, and the liquid refrigerant is vaporized while stopping the compressor. In addition, it is possible to obtain a refrigerator having a small number of components, being economical, and having high reliability and preventing troubles caused by liquid refrigerant.

Further, if a crankcase heater attached to warm the lubricating oil of the compressor is used as a heating means, a refrigerator having few components, being economical, and having high reliability and preventing trouble due to liquid refrigerant can be obtained. can get.

Further, as shown in FIG. 3, when the control means stops the operation of the compressor 1 and operates the electric heater to control the temperature of the compressor to a predetermined temperature, the evaporator Heater 21 or blower 1 for evaporator attached to
8 is operated, the liquid refrigerant sucked into the compressor 1 is vaporized, and the liquid refrigerant in the evaporator is also heated by the heating energy of the defrost heater or the air energy in the refrigerator blown by the blower. Because it will evaporate,
In particular, it is possible to obtain a highly reliable refrigerator that prevents trouble caused by liquid refrigerant from the evaporator during re-operation.

When the control means 10 operates the electric heater as described above to control the temperature of the compressor to a predetermined temperature, the refrigerant of the condenser does not flow to the evaporator. Thus, for example, when the electric expansion valve 23 having the opening / closing function as the decompressor 3 is closed, or when the decompressor is closed by providing means having the opening / closing function, the refrigerant of the condenser does not flow to the evaporator. As a result, the liquid refrigerant in the evaporator is easily vaporized easily, so that it is possible to obtain a highly reliable refrigerator in which the trouble due to the liquid refrigerant from the evaporator at the time of re-operation is particularly prevented.

Further, the control means drives the compressor when the temperature of the compressor reaches a predetermined temperature, so that a trouble caused by the liquid refrigerant at the time of re-operation is surely prevented and stable operation is performed. A highly reliable refrigerator can be obtained.

Embodiment 2 FIG. 2 is a configuration diagram of a refrigerator according to Embodiment 2 of the present invention. As shown in FIG.
In the second embodiment, a gas-liquid separator 11 such as an accumulator is installed and added between the evaporator 5 and the compressor 1 in the first embodiment.
1 is connected to a crankcase chamber (oil storage chamber) of the compressor 1 via a control valve 13, and an oil return pipe 12 is added thereto. The control valve 13 is opened when the compressor is stopped when the ratio exceeds a predetermined value and the heating means is operated to control the temperature of the compressor to a predetermined temperature. The bottom of the accumulator 11 is located higher than the crankcase chamber of the compressor 1.
Is opened, the lubricating oil (refrigeration oil) accumulated at the bottom of the accumulator 11 returns to the crankcase chamber of the compressor 1.

Next, this operation will be described in detail with reference to FIG. First, when the refrigerator is operated, the refrigerant is compressed by the compressor 1 and flows into a condenser as a high-temperature and high-pressure gas, where it is condensed and becomes a high-pressure liquid. The refrigerant becomes a gas-liquid mixed refrigerant and flows to the evaporator 5, where the liquid refrigerant evaporates, and all of the liquid refrigerant becomes a gaseous state.
1 and is sucked into the compressor 1 through the compressor 1 to repeat the same operation again.

In this operating state, the refrigerant sucked into the compressor 1 is always in a gaseous state, that is, only a refrigerant having a wetness of 0 (dryness 1) is sucked. , That is, a signal in which the liquid ratio is equal to or less than a predetermined value, is transmitted to the determination means 9. For transmission, the control means 10 opens the control valve 13 at predetermined time intervals while continuing the operation of the compressor 1, and lubricates oil (refrigeration oil) accumulated at the bottom of the accumulator 11 by a head difference to the crankcase of the compressor 1. Repeat the operation while returning to the room.

However, due to sudden changes in the cooling load and operating conditions, etc., the adjustment of the refrigerant flow rate in the pressure reducer was not successful, and the evaporator 5
If the liquid refrigerant cannot be gasified at all, that is,
A large amount of liquid refrigerant passes through the suction pipe 6 and accumulator 11
Although the gas refrigerant is separated here and the gas refrigerant is allowed to flow to the compressor 1 as much as possible, if this state continues and the liquid refrigerant continuously flows into the accumulator 11, the capacity of the accumulator 11 eventually exceeds the capacity. That is, the liquid refrigerant overflows and flows to the compressor 1.

Next, the liquid ratio of the liquid refrigerant flowing to the compressor 1 is detected by the refrigerant liquid ratio detecting means 8 and transmitted to the discriminating means 9, so that the discriminating means 9 uses a liquid bag which leads to damage of the compressor 1. It is determined whether or not there is, in other words, whether or not the detected liquid refrigerant ratio is equal to or less than a predetermined value, and the result of the determination is transmitted to the control means 10.

Therefore, based on the transmitted judgment result, the control means 10 judges that, when the detection result is equal to or less than the predetermined value, the situation does not damage the compressor 1 as described above. The control means 10 continues the operation of the compressor 1. However, when the pressure is equal to or more than the predetermined value, the control means 10 stops the operation of the compressor 1, opens the control valve provided in the oil return pipe, and removes the lubricating oil and the liquid refrigerant accumulated at the bottom of the accumulator 11 from the compressor. The lubricating oil, the liquid refrigerant, and the liquid refrigerant drawn into the compressor 1 are warmed by an electric heater as a heating means.

Next, the compressor 1 is warmed to a predetermined temperature by this series of operations, and the compressor temperature detecting means 8 detects from the detected temperature that the liquid refrigerant flowing into the compressor has been gasified. Is transmitted to the control means 10, so that the control means 10 drives the compressor 1. Therefore, the compressor 1 compresses the gasified refrigerant. In this case, even if the refrigerant liquid flows without gas in the evaporator due to a change in the response speed of the device or operating conditions, the refrigerant liquid is separated by the accumulator and stored. During operation, the compressor 1 surely compresses the gasified refrigerant.

The series of heating operations of the electric heater include, for example, supplying a constrained voltage to the electric motor 1a of the compressor 1 and stopping the compressor 1 while using the reactive power to stop the compressor 1a.
Or in other words, a weak current that does not start the compressor motor 1a flows through the motor 1a, and the compressor 1 is warmed by the heat generated by the windings due to this current, and the liquid refrigerant that has been backed up and the liquid from the accumulator 11 The refrigerant may be heated and vaporized, or may be heated and vaporized by a crankcase heater attached to warm the lubricating oil of the compressor, or may be heated and vaporized by a heater separately provided in the compressor. .

As described above, the refrigerant liquid ratio detecting means detects the liquid ratio of the refrigerant sucked into the compressor via the accumulator, and based on the detection result, the liquid ratio of the refrigerant becomes equal to or more than the predetermined value. When the control means stops the compressor, the heating means is operated to keep the temperature of the compressor at a predetermined temperature, and an oil return pipe connecting the bottom of the accumulator and the oil storage chamber of the compressor. Open the control valve of
In addition to avoiding damage to the compressor caused by the liquid back exceeding a predetermined value due to continuous return of the liquid refrigerant during operation, the liquid refrigerant sucked into the compressor and the liquid refrigerant in the accumulator are gasified. Therefore, it is possible to more reliably obtain a highly reliable refrigerator in which trouble due to the liquid refrigerant during operation and restart is prevented.

Further, the control means drives the compressor when the temperature of the compressor reaches a predetermined temperature, so that the operation is performed after gasifying the liquid refrigerant sucked into the compressor and the liquid refrigerant in the accumulator. Therefore, it is possible to more reliably obtain a highly reliable refrigerator that prevents a trouble caused by the liquid refrigerant at the time of re-operation and performs stable operation.

[0041]

Since the present invention is configured as described above, it has the following effects.

The liquid ratio of the refrigerant sucked into the compressor is detected by the refrigerant liquid ratio detecting means. Based on the detection result, when the liquid ratio of the refrigerant exceeds a predetermined value, the control means stops the compressor. At the same time, the heating means is operated to control the temperature of the compressor to a predetermined temperature, so that damage to the compressor caused by liquid back exceeding a predetermined value is avoided, and suction to the compressor is performed. Since the liquid refrigerant thus obtained is gasified, a highly reliable refrigerator that prevents troubles caused by the liquid refrigerant during operation and re-operation can be obtained.

Further, the heating means comprises an electric motor incorporated in the compressor, and the control means supplies the constrained voltage to the electric motor so as to stop the compressor and control the temperature of the compressor to a predetermined temperature. Since the control means only supplies the constrained voltage to the motor, the liquid refrigerant is vaporized while the compressor is stopped.Therefore, the number of components is small, the cost is low, and reliability due to troubles caused by the liquid refrigerant is prevented. Refrigeration machine with high temperature can be obtained.

Further, the heating means comprises an electric heater which is attached to the compressor and warms the lubricating oil of the compressor. The electric heater is operated by the control means so that the temperature of the compressor becomes a predetermined temperature. Control, the number of components is small,
An economical and highly reliable refrigerator that prevents troubles due to liquid refrigerant can be obtained.

When the control means operates the heating means so that the temperature of the compressor becomes a predetermined temperature, the control means operates the defrost heater attached to the evaporator. Therefore, a highly reliable refrigerator that can prevent trouble caused by liquid refrigerant from the evaporator at the time of re-operation can be obtained.

Further, when the control means operates the heating means to control the temperature of the compressor to a predetermined temperature, the control means drives the blower of the evaporator, so that the liquid refrigerant in the evaporator is also vaporized. In particular, it is possible to obtain a highly reliable refrigerator that prevents troubles due to liquid refrigerant from the evaporator at the time of re-operation.

When the control means operates the heating means to control the temperature of the compressor to a predetermined temperature, the pressure reducer is closed so that the refrigerant of the condenser does not flow to the evaporator. Because the liquid refrigerant in the evaporator is surely vaporized,
In particular, it is possible to obtain a highly reliable refrigerator that prevents trouble caused by liquid refrigerant from the evaporator during re-operation.

Further, the refrigerant liquid ratio detecting means detects the liquid ratio of the refrigerant sucked into the compressor via the accumulator,
Based on the detection result, when the liquid ratio of the refrigerant becomes equal to or more than a predetermined value, the control unit stops the compressor and operates the heating unit so that the temperature of the compressor becomes the predetermined temperature, Since the control valve of the oil return pipe that connects the bottom of the accumulator and the oil reservoir of the compressor is opened, damage to the compressor caused by the liquid back exceeding a predetermined value due to continuous return of the liquid refrigerant during operation Liquefaction and the liquid refrigerant sucked into the compressor and the liquid refrigerant in the accumulator are gasified, so that a reliable refrigeration that reliably prevents troubles caused by the liquid refrigerant during operation and re-operation. Machine is obtained.

Further, since the control means drives the compressor when the temperature of the compressor reaches a predetermined temperature, troubles due to the liquid refrigerant at the time of re-operation are surely prevented, and stable operation is performed. A highly reliable refrigerator can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a refrigerator according to a first embodiment.

FIG. 2 is a schematic configuration diagram of a refrigerator according to a second embodiment.

FIG. 3 is a configuration diagram of another refrigerator according to the first embodiment.

FIG. 4 is a configuration diagram of another refrigerator according to the first embodiment.

FIG. 5 is a block diagram of a configuration showing conventional liquid compression protection control.

FIG. 6 is a schematic diagram and a timing chart of a motor winding showing a high-frequency open-phase current state according to the conventional liquid compression protection control.

[Explanation of symbols]

1 compressor, 1a compressor motor, 1b compression section,
1c compressor shell, 2 compressor power supply, 3
Condenser, 4 decompressor, 5 evaporator, 6 suction pipe,
7 Refrigerant liquid ratio detecting means, 8 Compressor temperature detecting means, 9 Judging device, 10 Refrigerator control device, 11
Accumulator, 12 oil return pipe, 13 solenoid valve, 15 crankcase heater, 16 evaporator temperature detection sensor, 17 freezer, 18 evaporator blower, 19 internal temperature detection sensor, 20 refrigerator control device, 21 defrost heater, 23 electricity Type expansion valve.

Claims (8)

[Claims] 1. A refrigerant liquid ratio for detecting a liquid ratio of refrigerant sucked into a compressor in a refrigerator in which a compressor having a heating means, a condenser, a decompressor, and an evaporator are sequentially connected by piping. Detecting means, based on the detection result of the liquid ratio detecting means, when the liquid ratio of the refrigerant has become a predetermined value or more,
Control means for stopping the compressor and operating the heating means to control the temperature of the compressor to a predetermined temperature. 2. The heating means comprises an electric motor incorporated in the compressor, and the control means supplies a constrained voltage to the electric motor to stop the compressor and to keep the compressor at a predetermined temperature. The refrigerator according to claim 1, wherein the control is performed such that 3. The heating means is attached to the compressor and comprises an electric heater for warming lubricating oil of the compressor, and the electric heater is operated by the control means so that the temperature of the compressor becomes a predetermined temperature. The refrigerator according to claim 1, wherein the control is performed such that 4. The defrosting heater mounted on the evaporator is operated when the control means operates the heating means so that the temperature of the compressor becomes a predetermined temperature. The refrigerator according to any one of claims 1 to 3. 5. The air blower of the evaporator when the control means operates the heating means to control the temperature of the compressor to a predetermined temperature. 4. The refrigerator according to any one of to 3 above. 6. The decompressor according to claim 1, wherein when the control unit operates the heating unit to set the temperature of the compressor to a predetermined temperature, refrigerant in the condenser does not flow to the evaporator. The refrigerator according to any one of claims 1 to 5, wherein the refrigerator is closed. 7. An accumulator provided between the evaporator and the compressor for separating the refrigerant into a liquid refrigerant and a gas refrigerant, and provided in parallel with a refrigerant pipe connecting the accumulator and the compressor. An oil return pipe connecting the bottom of the accumulator and the oil storage chamber of the compressor and returning the lubricating oil at the bottom to the oil storage chamber by a head difference; and A control valve for adjusting a flow of the air, wherein the control means opens the control valve when controlling the temperature of the compressor to a predetermined temperature. The refrigerator according to any one of the above. 8. The refrigerator according to claim 1, wherein said control means drives said compressor when a temperature of said compressor reaches a predetermined temperature.