JPH0634208A - Cooling device of electric article box of air conditioner - Google Patents

Abstract

PURPOSE:To obtain a cooling device of an electric article box of an air conditioner which makes it possible to prevent dew formation in the electric article box and to simplify a refrigerant circuit. CONSTITUTION:A refrigerant circuit 13 is constructed of a compressor 14, a four-way valve 15, a nonuse-side heat exchanger 16, a use-side heat exchanger 17, an accumulator 18, a pressure reducing device 19 and an intake piping 20. A number 22 denotes an auxiliary cooler provided as an attachment so as to enable execution of heat exchange for an electric article box 21, and a bypass circuit 23 is connected by piping to the intake piping 20 from a refrigerant branch port 25 through the auxiliary cooler 22. An electric expansion valve 24 is provided between the refrigerant branch port 25 and the auxiliary cooler 22 and a construction is made so that the opening of the electric expansion valve 24 is controlled in accordance with each operation mode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric box cooling device for an air conditioner in which the capacity of a compressor is controlled by an inverter.

[0002]

2. Description of the Related Art Conventionally, there is an air conditioner using a transistor inverter to control the capacity of a compressor.
The power transistors, diode modules, capacitors, and the like that form the inverter need to be cooled from the viewpoint of long life and prevention of deterioration of performance because the temperature rises due to heat generation. The most general cooling method is forced cooling with wind.

However, in the case of this air cooling system, there is a problem that dust in the cooling air is apt to adhere to the surface of the electric component, which lowers the reliability of the component. Further, when the non-use side heat exchanger of the air conditioner is installed in the machine room, the wind cooling method causes a rise in ambient temperature and has a problem that a sufficient cooling effect cannot be obtained.

Therefore, it has been proposed to use the refrigerant of the air conditioner itself to perform efficient cooling,
For example, there is one as shown in FIG. 6 disclosed in Japanese Utility Model Laid-Open No. 55-1156. In the figure, 1 is a variable capacity compressor driven by an inverter, 2 is a four-way valve, 3 is a non-use side heat exchanger, 4 is a heating decompression device, 5 is a cooling decompression device, and 6 is a use side heat exchange. Vessel, 7 is accumulator, 8,
9 is a check valve. Further, 10 is a capillary tube provided in an open path from the pipe connecting the pressure reducing devices 4 and 5 to the accumulator 7 via the auxiliary cooler 11, and 12 is the auxiliary cooler 11.
It is an electrical box that can exchange heat with.

The solid arrow indicates the flow direction of the refrigerant during the cooling operation, and the broken arrow indicates the flow direction of the refrigerant during the heating operation.

Next, the operation will be described. First, during the cooling operation, the high-temperature and high-pressure gas refrigerant compressed by the compressor 1 enters the non-use side heat exchanger 3 through the four-way valve 2 and radiates heat to the atmosphere to be condensed and liquefied to form a high-pressure liquid refrigerant. Becomes This high-pressure liquid refrigerant is guided to the cooling decompression device 5 through the check valve 8 and is decompressed to become a low-pressure gas-liquid two-phase refrigerant, which enters the use side heat exchanger 6 and collects heat from the indoor air to cool it. Along with
The refrigerant evaporates to a low-pressure gas refrigerant and is sucked into the compressor 1 via the accumulator 7.

During the heating operation, by switching the four-way valve 2, the high-temperature and high-pressure gas refrigerant discharged from the compressor 1 enters the heat exchanger 6 on the use side and radiates heat to indoor air to heat the refrigerant, and at the same time, the refrigerant itself. Is condensed into a high-pressure liquid refrigerant.
The high-pressure liquid refrigerant is decompressed by the heating decompression device 4 via the check valve 9, becomes a low-pressure gas-liquid two-phase refrigerant, is evaporated in the non-use side heat exchanger 3, and is accumulated in the compressor 1 via the accumulator 7. Inhaled.

Next, the supply of the refrigerant to the auxiliary cooler 11 attached to the electric component box 12 will be described. While the compressor 1 is in operation, the pipe portion connecting the cooling decompression device 5 and the heating decompression device 4 is a high-pressure liquid refrigerant, so the low-pressure gas-liquid two-phase refrigerant decompressed by the capillary tube 10 is an auxiliary cooler. 11, the heat is taken from the electric component box 12 to cool the electric component box 12.

[0009]

However, in the conventional air conditioner, since the capillary tube 10 has the function of adjusting the refrigerant flow rate that influences the cooling performance of the auxiliary cooler 11, the load fluctuation of the compressor 1 is prevented. On the other hand, it cannot be adjusted appropriately. That is,
Since the flow rate of the refrigerant passing through the capillary tube 10 is governed by the high pressure of the inflow portion of the capillary tube 10, it is almost constant regardless of the capacity of the compressor 1, but the electric heat-generating component (Fig. The calorific value of (not shown) is almost proportional to the capacity of the compressor 1. Therefore, when the capacity of the compressor 1 is reduced, the cooling performance becomes excessive, and there is a problem that dew condensation occurs in the electrical component box 12.

Further, since the ambient temperature during the heating operation is lower than that during the cooling operation, the required cooling performance of the auxiliary cooler 11 may be small, but there is no adjusting function and there is the same problem as described above.

Further, since it is necessary to supply the refrigerant to the auxiliary cooler 11 during both the cooling operation and the heating operation, it is necessary to always form the high-pressure liquid refrigerant portion in any operation mode, which complicates the refrigerant circuit. There was also a problem.

An object of the present invention is to provide an electric component box cooling device for an air conditioner capable of preventing dew condensation in the electric component box and simplifying the refrigerant circuit.

[0013]

The present invention has the following constitution in order to achieve the above-mentioned object.
That is, a compressor having a variable capacity, a four-way valve, a heat exchanger on the non-use side, a pressure reducing device, a refrigerant circuit consisting of a heat exchanger on the use side and an accumulator, an electric component box storing electric heating components, and an electric component box. An auxiliary cooler attached for heat exchange, and a refrigerant branch port provided in the middle of the refrigerant pipe connecting the non-use side heat exchanger and the pressure reducing device, through the auxiliary cooler and connected to the suction pipe of the accumulator. A bypass circuit capable of supplying refrigerant to the auxiliary cooler, an electric expansion valve provided between the refrigerant branch port and the auxiliary cooler in the bypass circuit, and a valve for controlling the valve opening degree of the electric expansion valve An opening control device is provided, and the valve opening of the electric expansion valve is controlled according to the operating capacity of the compressor and each operation mode of cooling, heating, and defrosting of the air conditioner. .

Further, a refrigerant circuit comprising a variable capacity compressor, a four-way valve, a non-use side heat exchanger, a pressure reducing device, a use side heat exchanger and an accumulator, an electric component box accommodating electric heating components, and this electric An auxiliary cooler attached to the product box for heat exchange, and a refrigerant branch port provided in the middle of a refrigerant pipe connecting the non-use side heat exchanger and the pressure reducing device, to the suction pipe of the accumulator through the auxiliary cooler. Bypass circuit that can be connected to supply a refrigerant to the auxiliary cooler,
In this bypass circuit, an electric expansion valve provided between the refrigerant branch port and the auxiliary cooler, a valve opening control device that controls the valve opening of the electric expansion valve, and the ambient temperature of the electrical component box And a temperature detecting means for detecting the temperature, and the valve opening control device corrects and controls the valve opening of the electric expansion valve based on the temperature detected by the temperature detecting means.

Further, a refrigerant circuit comprising a variable capacity compressor, a four-way valve, a non-use side heat exchanger, a pressure reducing device, a use side heat exchanger and an accumulator, an electric component box accommodating electric heating components, and this electric An auxiliary cooler attached to the product box for heat exchange, and a refrigerant branch port provided in the middle of a refrigerant pipe connecting the non-use side heat exchanger and the pressure reducing device, to the suction pipe of the accumulator through the auxiliary cooler. Bypass circuit that can be connected to supply a refrigerant to the auxiliary cooler,
In this bypass circuit, a capillary tube provided between the refrigerant branch port and the auxiliary cooler, an electromagnetic valve connected in parallel to the capillary tube, and a valve opening / closing control device that controls opening / closing of the electromagnetic valve are provided, and a heating operation is performed. Is a configuration in which the solenoid valve is opened and the solenoid valve is closed during the cooling operation and the defrost operation.

Further, a refrigerant circuit comprising a variable capacity compressor, a four-way valve, a non-use side heat exchanger, a pressure reducing device, a use side heat exchanger and an accumulator, and an electric component box accommodating an electric heating component, Auxiliary cooler attached to the electrical equipment box so that heat can be exchanged, and a suction pipe of the accumulator passing through the auxiliary cooler from a refrigerant branch port provided in the middle of a refrigerant pipe connecting the non-use side heat exchanger and the pressure reducing device. A bypass circuit capable of supplying a refrigerant to the auxiliary cooler by connecting to, a capillary tube provided between the refrigerant branch port and the auxiliary cooler in the bypass circuit, and a solenoid valve connected in parallel to the capillary tube, A valve opening / closing control device for controlling the opening / closing of the electromagnetic valve is provided, and the valve opening / closing control device is configured to close the electromagnetic valve for a predetermined time after the activation of the compressor.

[0017]

According to the electromagnetic product box cooling device for an air conditioner of the first aspect, the bypass circuit is composed of a refrigerant circuit having a variable capacity compressor and an electric product box accommodating electric heat-generating components. Since the refrigerant branch port between the exchanger and the pressure reducing device was connected to the intake pipe of the accumulator through the auxiliary cooler attached to the electrical component box via the electric expansion valve, the amount of refrigerant supplied to the auxiliary cooler was properly controlled. It In addition, the amount of refrigerant supplied to the auxiliary cooler can be controlled according to the operating capacity of the compressor and the required cooling amount that varies depending on the cooling / heating / defrosting operation modes.

According to the electric component box cooling device for an air conditioner of the second aspect, it is possible to control the amount of refrigerant supplied to the auxiliary cooler in accordance with the required cooling amount which changes depending on the ambient temperature of the electric component box.

According to the electric component box cooling device of the air conditioner of the third aspect, the refrigerant circuit having the variable capacity compressor and the electric component box accommodating the electric heating component are used, and the bypass circuit does not use the heat exchange. Since the refrigerant branch port was connected from the refrigerant branch port to the intake pipe of the accumulator through the parallel circuit of the capillary tube and the solenoid valve through the auxiliary cooler attached to the electrical equipment box, the amount of refrigerant supplied to the auxiliary cooler was controlled by the solenoid valve. It can be adjusted by controlling. Also, during heating operation, by opening the solenoid valve, the refrigerant can be supplied to the auxiliary cooler even under the condition where the pressure difference is relatively small, and during the cooling operation and the defrost operation, the solenoid valve is closed to close the capillary tube. Due to the relatively large pressure difference generated in the subcooler, the refrigerant can be supplied to the auxiliary cooler only by the capillary tube.

According to the electric component box cooling device of the air conditioner of the fourth aspect, the solenoid valve is controlled to be closed for a predetermined time when the compressor is started during the heating operation. Even if the pressure changes, the flow rate of the refrigerant flowing through the auxiliary cooler can be suppressed.

[0021]

【Example】

Example 1. An embodiment of the present invention is shown in FIG. 1. In the figure, 13 is a refrigerant circuit, and a variable capacity compressor 14 driven by an inverter, a four-way valve 15, a non-use side heat exchanger 16, a use side heat exchange. The container 17, the accumulator 18, the pressure reducing device 19, and the suction pipe 20 of the accumulator 18 are included. Reference numeral 21 is an electric component box that houses an electric heating component, and 22 is an auxiliary cooler that is attached to the electric component box 21 so that heat can be exchanged. Reference numeral 23 is a bypass circuit pipe-connected to a suction pipe 20 of the accumulator 18 from a refrigerant branch port 25 provided in the middle of the refrigerant pipe connecting the non-use side heat exchanger 16 and the pressure reducing device 19 via an auxiliary cooler 22. . Refrigerant branch port 25 and auxiliary cooler 22
An electric expansion valve 24 is provided between the two. Further, 26 is a valve opening control device for controlling the valve opening of the electric expansion valve 24, and 30 is temperature detecting means for detecting the ambient temperature of the electric component box 21.

In the figure, solid arrows indicate the direction of refrigerant flow during cooling operation, and broken arrows indicate the direction of refrigerant flow during heating operation. During the cooling operation, the high-temperature and high-pressure gas refrigerant compressed by the compressor 14 enters the non-use side heat exchanger 16 through the four-way valve 15 and radiates heat to the atmosphere to be condensed and liquefied to become a high-pressure liquid refrigerant. This high-pressure liquid refrigerant is decompressed by the decompression device 19 to become a low-pressure gas-liquid two-phase refrigerant, enters the use-side heat exchanger 17, collects heat from the indoor air and cools it, and evaporates the refrigerant to form a low-pressure gas. Becomes refrigerant and accumulator 1
8 and is sucked into the compressor 14 via. During heating operation,
By switching the four-way valve 15, the high-temperature and high-pressure gas refrigerant discharged from the compressor 14 enters the use-side heat exchanger 17 to radiate heat to indoor air to heat the refrigerant, and the refrigerant itself is condensed to form a high-pressure liquid. It becomes a refrigerant. High-pressure liquid refrigerant is a decompression device 1
It is decompressed at 9, becomes a low-pressure gas-liquid two-phase refrigerant, evaporates at the non-use side heat exchange gas 16, and is sucked into the compressor 14 via the accumulator 18.

Next, the operation of the bypass circuit 23 will be described. The refrigerant state at the refrigerant branch port 25 provided in the refrigerant pipe connecting the non-use side heat exchanger 16 and the pressure reducing device 19 becomes a high pressure liquid refrigerant during the cooling operation and a low pressure gas-liquid two-phase refrigerant during the heating operation. Also, accumulator 1
The refrigerant in the suction pipe 20 of No. 8 is in a low-pressure gas refrigerant state, and is always lower in pressure than the refrigerant branch port 25. Therefore, in the bypass circuit 23, a refrigerant flow from the refrigerant branch port 25 to the suction pipe 20 of the accumulator 18 is generated, so that the auxiliary cooler 22
A low-temperature refrigerant is supplied to the device to collect heat from the electrical component box 21 to cool it. The amount of refrigerant supplied to the auxiliary cooler 22 is adjusted by the electric expansion valve 24.

Next, the valve opening control in the valve opening control device 26 of the electric expansion valve 24 will be described with reference to FIGS. 2, 3 and 4. FIG. 2 is a flowchart showing a state in which the valve opening degree of the electric expansion valve 24 is set / output controlled. In step 31, it is determined whether or not the compressor 14 is in operation, and the valve opening control of the electric expansion valve 24 is performed only when the compressor 14 is in operation. When the compressor 14 is stopped, step 39 is performed. The valve opening output S = 0, that is, the valve is fully closed. When the compressor 14 is in operation, the process proceeds to step 32, the operation mode is determined, and in the case of cooling, the valve opening degree of the electric expansion valve 24 is controlled by steps 34 to 38. That is, step 34
Then, the compressor operating capacity set by the capacity control means (not shown) for controlling the operating capacity of the compressor 14 according to the indoor cooling load is read, and in step 35, the cooling reference opening preset by the compressor operating capacity is read. The degree S1 is calculated. Further, in step 36, the ambient temperature of the electrical component box 21 is detected by the temperature detecting means 30, and based on this detected temperature, step 37
The cooling opening correction value ΔS1 is calculated in step 38, and the valve opening output “S = S1 + ΔS1” is determined in step 38 based on the cooling reference opening S1 and the cooling opening correction value ΔS1. In step 32, in the case of heating operation, it is determined in step 33 whether or not it is defrost operation. If it is not defrost operation, in steps 40 to 44, the compressor operating capacity and Electrical box 21
The valve opening output “S = S2 + ΔS2” is determined on the basis of the ambient temperature of. If the defrost operation is performed in step 33, the defrost reference opening S3 is set in step 45, and the process proceeds to step 46 to determine the valve opening output "S = S3".

FIG. 3 is a characteristic diagram for setting the reference valve opening degree of the electric expansion valve 24 according to the operating capacity of the compressor 14.
In the figure, S1 is a cooling reference opening degree diagram, S2 is a heating reference opening degree diagram, and the reference opening degrees S1 and S2 are set so as to increase substantially proportionally as the compressor operating capacity increases. There is. That is, the amount of heat generated by the electric heating components housed in the electric component box 21 increases due to an increase in the operating capacity of the compressor 14, so the required cooling amount of the electric component box 21 also increases. Therefore,
By setting the reference opening degree of the electric expansion valve 24 based on the operating capacity of the compressor 14, the amount of refrigerant supplied to the auxiliary cooler 22 can be appropriately controlled. In addition, since the inlet refrigerant state of the electric expansion valve 24 is a high-pressure liquid refrigerant in the case of cooling, and a low-pressure two-phase refrigerant in the case of heating, the heating reference opening S2 is shown in FIG. 3 compared to the cooling reference opening S1. It is set extremely large as shown.

FIG. 4 is a characteristic diagram for setting the correction amount of the valve opening degree of the electric expansion valve 24 based on the ambient temperature of the electric component box 21. In the figure, the correction amount is a ratio to the reference opening shown in FIG. 3, and the cooling opening correction value ΔS1 and the heating opening correction value ΔS2 are independently set. When the ambient temperature is high, the required cooling amount of the electric component box 21 increases, so the correction values Δ1 and Δ2 are set to be large.

Example 2. Next, another embodiment of the present invention is shown in FIG. The same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the figure, 27 is a capillary tube provided between the refrigerant branch port 25 and the auxiliary cooler 22 and connected in parallel to the solenoid valve 28. Reference numeral 29 denotes a valve opening / closing control device that controls opening / closing of the solenoid valve 28.

Next, the operation will be described. Operation during cooling operation and heating operation with refrigerant, and auxiliary cooler 2
The cooling action of the electric component box 21 by 2 is the same as that of the first embodiment shown in FIG.

The operation of the bypass circuit 23 of this embodiment will be described including the control state of the valve opening / closing control device 29. In the cooling operation, the electromagnetic valve 28 maintains the open circuit state, and the refrigerant is supplied to the auxiliary cooler 22 only via the capillary tube 27. That is, in the cooling operation, since the refrigerant branch port 25 is a high pressure refrigerant liquid and the suction pipe 20 of the accumulator 18 is a low pressure gas refrigerant, a sufficient refrigerant flow rate can be secured only by the capillary tube 27 and the electric component box 21. The cooling performance of can be demonstrated. Further, in the heating operation, the electromagnetic valve 28 is opened, and the refrigerant is supplied to the auxiliary cooler 22 via the parallel opening of the capillary tube 27 and the electromagnetic valve 28. That is, in the heating operation, since the refrigerant branch port 25 is a low-pressure gas-liquid two-phase refrigerant, it is not possible to secure a sufficient refrigerant flow rate only by the capillary tube 27. Therefore, the electromagnetic valve 28 is opened to open the electrical component box 21. The auxiliary cooler 22 is supplied with a sufficient flow rate of the refrigerant to obtain the required cooling performance. In the case of the defrost operation that occurs in the heating operation, the refrigerant flow in the cooling operation (indicated by the solid arrow in the figure) is set. Therefore, the electromagnetic valve 28 is closed and the flow rate of the refrigerant supplied to the auxiliary cooler 22 is reduced. It is controlled so that it does not become excessive.

Immediately after starting the compressor 14,
Since a rapid pressure drop occurs in the suction pipe 20 of the accumulator 18, a sufficient refrigerant flow rate can be secured only by the capillary tube 27. Therefore, if the solenoid valve 28 is opened immediately after the compressor 14 is started in the heating operation, the refrigerant flow rate becomes excessive.
The solenoid valve 28 is controlled to be closed for a predetermined time immediately after the start.

[0032]

As described above, according to the electric component box cooling device for an air conditioner according to claim 1 of the present invention, an electric component box containing a refrigerant circuit having a variable capacity compressor and an electric heating component. The bypass circuit is connected to the intake pipe of the accumulator from the refrigerant branch port between the non-use side heat exchanger of the refrigerant circuit and the pressure reducing device through the auxiliary expansion cooler attached to the electrical component box via the electric expansion valve. At the same time, a valve opening control device was installed to control the valve opening of the electric expansion valve according to the operating capacity of the compressor and each operating mode of cooling, heating, and defrosting. It is possible to prevent the occurrence of dew condensation in the electric component box due to a change in the amount of the refrigerant supplied to the electric component box. In addition, a bypass circuit for cooling the electrical component box is connected between the refrigerant branch port whose pressure changes depending on the operation mode of the air conditioner and the intake pipe of the accumulator, and is supplied at the valve opening of the electric expansion valve. The amount of refrigerant can be controlled, and the refrigerant circuit can be simplified.

According to the electric component box cooling device for an air conditioner according to a second aspect of the present invention, the valve of the electric expansion valve is opened based on the temperature detected by the temperature detecting device for detecting the ambient temperature of the electric component box. Since the degree is corrected and controlled, the amount of refrigerant supplied to the auxiliary cooler can be appropriately controlled according to the required cooling amount of the electrical component box that changes depending on the ambient temperature.

According to a third aspect of the present invention, there is provided an electric component box cooling device for an air conditioner, which comprises a refrigerant circuit having a variable capacity compressor and an electric component box accommodating an electric heating component. The bypass circuit is connected from the refrigerant branch port between the heat exchanger on the unused side of the refrigerant circuit and the pressure reducing device to the suction pipe of the accumulator through the auxiliary open cooler attached to the electrical component box through the parallel opening of the capillary tube and the solenoid valve. Since the solenoid valve is opened during the heating operation and is closed during the cooling operation and the defrost operation, the valve opening / closing control device is provided, so that the refrigerant supply amount to the auxiliary cooler can be secured by a relatively simple refrigerant circuit configuration.

According to the electric component box cooling device for an air conditioner according to a fourth aspect of the present invention, since the circuit is closed for a predetermined time immediately after the compressor is started, there is a sudden pressure change due to the start of the compressor. Even in this case, the amount of refrigerant flowing through the auxiliary cooler can be suppressed.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an air conditioner according to a first embodiment of the present invention.

FIG. 2 is a flow chart showing a control state by the valve opening control device in FIG.

FIG. 3 is a characteristic diagram for setting the reference valve opening degree in FIG. 2 according to the operating capacity of the compressor.

FIG. 4 is a characteristic diagram for setting a valve opening correction value in FIG. 2 according to ambient temperature.

FIG. 5 is an overall configuration diagram of an air conditioner according to a second embodiment of the present invention.

FIG. 6 is an overall configuration diagram of a conventional air conditioner.

[Explanation of symbols]

 13 Refrigerant circuit 14 Compressor 15 Four-way valve 16 Non-use side heat exchanger 17 Use side heat exchanger 18 Accumulator 19 Pressure reducing device 20 Suction pipe 21 Electric component box 22 Auxiliary cooler 23 Bypass circuit 24 Electric expansion valve 25 Refrigerant branch port 26 Valve opening control device 27 Capillary tube 28 Electromagnetic valve 29 Valve opening / closing control device 30 Temperature detection device

Claims (4)

[Claims] 1. A refrigerant circuit comprising a variable capacity compressor, a four-way valve, a non-use side heat exchanger, a pressure reducing device, a use side heat exchanger and an accumulator, an electric component box accommodating an electric heating component, and this electric An auxiliary cooler attached to the product box for heat exchange, and a refrigerant branch port provided in the middle of a refrigerant pipe connecting the non-use side heat exchanger and the pressure reducing device, to the suction pipe of the accumulator through the auxiliary cooler. A bypass circuit that is connected to supply the refrigerant to the auxiliary cooler, an electric expansion valve provided between the refrigerant branch port and the auxiliary cooler in the bypass circuit, and a valve opening degree of the electric expansion valve A valve opening control device for controlling the electric expansion valve is controlled according to the operating capacity of the compressor and the cooling, heating, and defrosting operation modes of the air conditioner. To A cooler for electric box of air conditioners. 2. A refrigerant circuit comprising a variable capacity compressor, a four-way valve, a heat exchanger on the non-use side, a pressure reducing device, a heat exchanger on the use side and an accumulator; An auxiliary cooler attached to the product box for heat exchange, and a refrigerant branch port provided in the middle of a refrigerant pipe connecting the non-use side heat exchanger and the pressure reducing device, to the suction pipe of the accumulator through the auxiliary cooler. A bypass circuit that is connected to supply the refrigerant to the auxiliary cooler, an electric expansion valve provided between the refrigerant branch port and the auxiliary cooler in the bypass circuit, and a valve opening degree of the electric expansion valve A valve opening control device for controlling and a temperature detecting means for detecting the ambient temperature of the electric component box, and the valve opening control device opens the valve of the electric expansion valve based on the temperature detected by the temperature detecting means. Degree An electric component cooling device for an air conditioner, which is characterized by performing correction control. 3. A refrigerant circuit comprising a variable capacity compressor, a four-way valve, a non-use side heat exchanger, a pressure reducing device, a use side heat exchanger and an accumulator, an electric component box accommodating an electric heat generating component, and this electric machine. An auxiliary cooler attached to the product box for heat exchange, and a refrigerant branch port provided in the middle of a refrigerant pipe connecting the non-use side heat exchanger and the pressure reducing device, to the suction pipe of the accumulator through the auxiliary cooler. A bypass circuit which is connected to supply the refrigerant to the auxiliary cooler, a capillary tube provided between the refrigerant branch port and the auxiliary cooler in the bypass circuit, and a solenoid valve connected in parallel to the capillary tube, A valve opening / closing control device for controlling opening / closing of a solenoid valve is provided, wherein the solenoid valve is opened during a heating operation, and the solenoid valve is closed during a cooling operation and a defrost operation. Cooling device for electric box of air conditioner. 4. A refrigerant circuit comprising a variable capacity compressor, a four-way valve, a non-use side heat exchanger, a pressure reducing device, a use side heat exchanger and an accumulator, an electric component box accommodating an electric heat generating component, and this electric component. An auxiliary cooler attached to the product box for heat exchange, and a refrigerant branch port provided in the middle of a refrigerant pipe connecting the non-use side heat exchanger and the pressure reducing device, to the suction pipe of the accumulator through the auxiliary cooler. A bypass circuit which is connected to supply the refrigerant to the auxiliary cooler, a capillary tube provided between the refrigerant branch port and the auxiliary cooler in the bypass circuit, and a solenoid valve connected in parallel to the capillary tube, A valve opening / closing control device for controlling opening / closing of a solenoid valve, wherein the valve opening / closing control device is configured to close the solenoid valve for a predetermined time after the compressor is activated. Class box cooler.