JP6890919B2 - Closed compressor and refrigeration cycle equipment - Google Patents

Description

Embodiments of the present invention relate to a closed compressor and a refrigeration cycle device including the closed compressor.

A closed compressor in which the coating film of the accumulator is thicker than that of the closed container has been proposed.

In a closed compressor, it is desirable to thicken not only the accumulator but also the coating film of the closed container to improve the corrosion resistance. However, since heat-generating parts such as an electric motor are housed inside the closed container, if the coating film is thickened, the heat dissipation of the closed container is lowered.

Japanese Unexamined Patent Publication No. 2011-236479

An object of the present invention is to provide a closed compressor capable of reliably protecting a closed container from rust and sufficiently ensuring heat dissipation of the closed container.

The closed-type compressor of the embodiment is a closed-type compressor including a compression mechanism for compressing the refrigerant and a closed container containing the compression mechanism, and the closed container has a bottom portion and the bottom portion thereof. The lid on the opposite side, the bottom and the body connecting the lids, the first welded part where the bottom and the body are joined by welding, and the lid and the body are joined by welding. The closed container is configured to have a coating film having a locally changed thickness, and has a coating film formed on each of the bottom portion, the lid portion, and the body portion. , The coating film on the body has an arithmetic average swell of 0.3 μm or more, and based on the coating film on the body, the coating film on the bottom and lid is 1.5 times larger, the first welded part and the second The coating film on the welded portion is 1.75 times thicker.

It is a schematic block diagram which shows the refrigerating cycle apparatus of one Embodiment. It is sectional drawing which shows by cutting out a part of the closed type compressor shown in FIG. It is sectional drawing which shows by cutting a closed container in F3 part in FIG. It is sectional drawing which shows by cutting a closed container in F4 part in FIG. It is sectional drawing which shows by cutting a closed container in F5 part in FIG. It is sectional drawing which shows by cutting the closed container in F6 part in FIG. It is a schematic diagram explaining the waviness and roughness of the coating film surface. It is a figure which shows the cross-sectional curve obtained from each part of a closed container and the coating film surface formed on the test piece. It is a figure which shows the cross-sectional curve obtained from the coating film surface formed on the test piece. It is a figure which shows the arithmetic mean roughness and the arithmetic mean waviness of the coating film surface formed on the bottom part and the test piece.

Hereinafter, the refrigeration cycle apparatus 1 and the closed compressor 2 according to the embodiment of the present invention will be described with reference to FIGS. 1 to 10.
FIG. 1 is a schematic configuration diagram showing an embodiment of the refrigeration cycle device 1. The refrigeration cycle device 1 includes a closed compressor 2, a radiator (condenser) 3 connected to the closed compressor 2, an expansion device 4 connected to the radiator 3, an expansion device 4, and a closed compression. It includes an evaporator 5 connected between the machines 2.

The closed compressor 2 is, for example, a rotary type compressor that compresses the low-pressure vapor-phase refrigerant taken into the inside and changes it into a high-temperature and high-pressure vapor-phase refrigerant. The radiator 3 dissipates heat from the high-temperature and high-pressure gas-phase refrigerant sent from the closed compressor 2, and changes the vapor-phase refrigerant into a high-pressure liquid-phase refrigerant.

The expansion device 4 lowers the pressure of the high-pressure liquid-phase refrigerant sent from the radiator 3 and changes it into a low-temperature low-pressure liquid-phase refrigerant. The evaporator 5 vaporizes the liquid phase refrigerant sent from the expansion device 4 and changes it into a low pressure gas phase refrigerant. At this time, the heat of vaporization is taken away by the phase-changing refrigerant, and the periphery of the evaporator 5 is cooled. The vapor phase refrigerant that has taken away the heat of vaporization is taken into the closed compressor 2 again.

As described above, in the refrigeration cycle device 1, the refrigerant as the working fluid circulates while changing the phase between the gas phase refrigerant and the liquid phase refrigerant. Heat is dissipated from the refrigerant in the process of phase change from the gas phase refrigerant to the liquid phase refrigerant, and heat is absorbed by the refrigerant in the process of phase change from the liquid phase refrigerant to the vapor phase refrigerant. Heating and cooling are performed using these heat dissipation and heat absorption.

The sealed compressor 2 includes a compressor main body 11 and an accumulator 12. The accumulator 12 is a gas-liquid separator and is provided between the evaporator 5 and the compressor main body 11.

FIG. 2 is a cross-sectional view showing a part of the sealed compressor shown in FIG. 1 with a cutout. The accumulator 12 is connected to the compressor main body 11 through the first and second suction pipes 13 and 14, and is configured to supply only the vapor phase refrigerant vaporized by the evaporator 5 to the compressor main body 11. There is.

The compressor main body 11 includes a rotating shaft 21, a compression mechanism unit 23 that compresses the gas phase refrigerant by the rotation of the rotating shaft 21, and a closed container 30 in which the rotating shaft 21 and the compression mechanism unit 23 are housed. There is. The compression mechanism unit 23 has an electric motor unit 22 that rotates the rotating shaft 21.

The rotating shaft 21 is arranged so as to share the axis X with the closed container 30. The electric motor unit 22 is arranged closer to the upper side of the rotating shaft 21. The compression mechanism unit 23 is arranged closer to the lower side of the rotating shaft 21. In the following description, the direction along the axis X may be referred to as the axial direction, the direction orthogonal to the axis X may be referred to as the radial direction, and the direction around the axis X may be referred to as the circumferential direction.

The electric motor unit 22 is, for example, an inner rotor type DC brushless motor, and is arranged with a tubular stator 24 fixed to the inner wall surface of the closed container 30 and inside the stator 24 at intervals in the radial direction. It is provided with a columnar rotor 25.

The compression mechanism unit 23 includes a first cylinder chamber 26, a second cylinder chamber 27 arranged below the first cylinder chamber 26, and a first roller provided in the first cylinder chamber 26. 28 and a second roller 29 provided in the second cylinder chamber 27 are provided.

The first and second rollers 28 and 29 are configured to be eccentrically rotatable while being in sliding contact with the inner peripheral surface of the first cylinder chamber 26 as the rotating shaft 21 rotates. The first and second suction pipes 13 and 14 of the accumulator 12 are connected to the first and second cylinder chambers 26 and 27, respectively.

The closed container 30 has a closed container base material 31 formed of a steel material or the like, and a coating film 32 for coating the closed container base material 31. The closed container 30 includes a bottom portion 33, a lid portion 34 arranged on the side opposite to the bottom portion 33, and a body portion 35 connecting the bottom portion 33 and the lid portion 34. The bottom portion 33 and the lid portion 34 are formed in a deep dish shape. The body portion 35 is formed in a cylindrical shape.

The bottom portion 33 and the body portion 35 are joined by welding, and a first welded portion 36 is formed between them along the circumferential direction. The lid portion 34 and the body portion 35 are joined by welding, and a second welded portion 37 is formed between them along the circumferential direction.

Conventionally, the coating thickness of the closed container 30 has been about 20 μm. However, in order to improve corrosion resistance, a thicker one, for example 30 μm, is desirable. Further, in the closed container 30, the lid portion 34 is more likely to be rusted than the body portion 35 because the condensed water adhering to the low pressure side pipe of the refrigeration cycle device is likely to fall on the lid portion 34. Further, the bottom portion 33 is more easily rusted than the body portion 35 due to the influence of the drain water stored in the bottom plate of the refrigeration cycle device. Further, the first and second welded portions 36 and 37 are also more likely to rust than the body portion 35 because the paint is hard to adhere to them.

Therefore, in the present embodiment, the coating film thickness of the closed container 30 is locally changed. That is, FIGS. 3, 4, 5, and 6 are cross-sectional views showing the closed container 30 cut at the F3 portion, the F4 portion, the F5 portion, and the F6 portion in FIG. The coating film 32b on the bottom portion 33, the coating film 32c on the lid portion 34, and the coating film 32d on the first and second welded portions 36 and 37 are formed thicker than the coating film 32a on the body portion 35, respectively.

In the examples of FIGS. 3, 4, 5, and 6, the thickness T1 of the coating film 32a on the body 35 is 40 μm, the thickness T2 of the coating film 32b on the bottom 33 is 60 μm, and the coating film 32c on the lid 34. The thickness T3 is 60 μm, and the thickness T4 of the coating film 32d at the second weld 37 is 70 μm.

Based on the coating film 32a of the body 35, the coating films 32b and 32c of the bottom 33 and the lid 34 are 1.5 times, and the coating films 32d of the first and second welds 36 and 37 are 1.75 times. It can be said that it is formed to the thickness of.

The coating film 32 of the present embodiment is formed by electrostatic spraying powder coating. First, the closed compressor 10 in which a set of members such as the closed container base material 31, the accumulator 12, the first and second suction pipes 13 and 14 are joined by welding or the like, and each member is not yet painted. Prepare.

The closed type compressor 10 is grounded, and the powder coating material to which the electric charge is applied is sprayed on the closed type compressor 10. When the powder coating material adhering to the closed type compressor 10 is melted by heating with a heating device after spraying, a coating film by powder coating can be formed on the surface of the closed type compressor 10.

Examples of the powder coating material include epoxy resin, polyester resin, acrylic resin and the like. In this embodiment, an epoxy resin and a polyester resin are mixed and used. The electrical characteristic conditions for applying an electric charge to the powder coating material are, for example, an output current of 1 to 50 μA and an output voltage of −50 kV to −100 kV or + 50 kV to + 100 kV. In order to prevent unevenness due to overcurrent, it is preferable to set the output current to a constant current. In order to suppress electrostatic repulsion between powder coatings, it is preferable to set the output voltage to a negative voltage.

In the present embodiment, the coating films 32b, 32c, 32d on the bottom portion 33, the lid portion 34, and the first and second welded portions 36, 37 are formed thicker than the coating film 32a on the body portion 35. In order to form such a coating film 32, the powder coating is sprayed on the bottom portion 33, the lid portion 34, and the first and second welded portions 36 and 37 for a longer period of time than the body portion 35.

By changing the length of the spraying time depending on the site, a closed container base material 31 in which the amount of powder coating adhered is locally changed is obtained. When the closed container base material 31 is heated by a heating device, a closed container 30 in which the thickness of the coating film 32 is locally changed can be obtained.

In this way, the thickness of the coating film including the body 35 of the closed container 30 is formed thicker than before, and the coating thickness of the closed container 30 is locally changed to obtain the coating film of the entire closed container 30. Compared with the case where the thickness is the same as the coating thickness of the first and second welded portions 36, 37 and the like, the decrease in heat dissipation can be suppressed.

FIG. 7 is a schematic view illustrating the roughness and waviness of the surface of the coating film 32. When the surface of the coating film 32 is measured with a surface roughness measuring machine, a measurement curve in which waves having various periods and amplitudes are combined can be obtained. Surface roughness is defined as waves with a relatively short period, waves with a longer period than surface roughness and regular periodicity are defined as undulations, and waves with the longest period such as the slope of a flat plate or the arc of a cylinder are defined as geometric deviations. To do.

The cross-sectional curved surface is obtained by removing the geometric deviation from the measurement curve, and represents roughness and waviness. The roughness is the fine unevenness on the surface of the coating film 32. The swell is a periodic undulation on the surface of the coating film 32.

FIG. 9 shows the arithmetic mean waviness Wa and the cross-sectional curve of the coating film surfaces of the test pieces B1 and B2 having the same coating as the conventional closed container. Each measurement was performed in accordance with JIS B0601: 2001 using a surface roughness measuring machine. The coating film of the test piece B1 is formed by dip coating. The coating film of the test piece B2 is formed by electrodeposition coating. The arithmetic mean swell Wa of the test piece B1 was 0.2 μm, and the arithmetic mean swell Wa of the test piece B2 was 0.1 μm. As described above, it was found that the surface of the coating film of the conventional closed container has an arithmetic mean waviness Wa formed on the surface having a minute value of 0.2 μm or less.

On the other hand, when the arithmetic mean waviness of the coating film surface becomes large, the unevenness of the surface becomes large, the surface area of the coating film that can come into contact with the outside air increases, and the heat dissipation of the coating film surface improves. Therefore, in the present embodiment, the coating film on the body 35 having the largest surface area of the closed container 30 has an arithmetic mean swell Wa of 0.3 μm or more, which is 1.5 times or more the conventional one.

FIG. 8 is an arithmetic mean waviness Wa and a cross-sectional curve of the coating film surfaces formed on the second welded portion 37, the bottom portion 33, the body portion 35, and the test pieces A1 and A2. Each measurement was performed in accordance with JIS B0601: 2001 using a surface roughness measuring machine. The coating films of the test pieces A1 and A2 are formed by powder coating like the body 35, but the spraying time of the powder coating is shorter than that of the body 35.

The coating film 32b on the bottom 33 had an arithmetic mean swell Wa larger than that on the coating film 32a on the body 35. The coating film 32d of the second welded portion 37 had an arithmetic mean swell Wa larger than that of the coating film 32a of the body 35, and further had an arithmetic mean swell Wa larger than that of the coating film 32b of the bottom 33. The coating film 32a of the body 35 had an arithmetic mean swell Wa larger than that of the test pieces A1 and A2. The coating film of the test piece A2 had an arithmetic mean waviness Wa of 0.3 μm.

FIG. 10 shows the arithmetic mean roughness Ra and the arithmetic mean waviness Wa of the coating film surfaces formed on the bottom 33 and the test pieces A1, A3, A4 and B3. The arithmetic mean roughness Ra and the arithmetic mean swell Wa were measured using a surface roughness measuring machine according to JIS B0601: 2001, respectively. The coating films of the test pieces A3 and A4 are formed by powder coating. The coating film of the test piece B3 is formed by electrodeposition coating.

In the bottom 33, the test pieces A1, A3, and A4 in which the coating film was formed by powder coating, the arithmetic mean waviness Wa of the coating film was formed larger than that in the test piece B3 in which the coating film was formed by electrodeposition coating. Further, in the bottom portion 33, the test pieces A1, A3 and A4, the ratio of the arithmetic mean waviness Wa / the arithmetic mean roughness Ra of the coating film was formed larger than that of the test piece B3.

In the closed compressor 2 and the refrigerating cycle device 1 of the present embodiment configured as described above, the coating film 32 of the closed container 30 is formed by powder coating. Since a thick coating film 32 can be formed as compared with electrodeposition coating or the like, the corrosion resistance of the closed container base material 31 can be improved and the closed container 30 can be more reliably protected from rust. Moreover, since sufficient rust prevention can be expected only by powder coating, man-hours can be reduced by omitting chemical conversion treatment such as zinc phosphate treatment.

Further, in the present embodiment, the coating film 32 is formed so that the arithmetic mean waviness Wa on the surface is 0.3 μm or more. Generally, when the coating film 32 becomes thicker, the heat dissipation property deteriorates, but in the present embodiment, by forming undulations on the surface of the closed container base material 31, the contact area with the outside air is increased to promote heat dissipation, and the coating film 32 The decrease in heat dissipation due to the increase in the thickness of the film is suppressed.

Further, in the closed container 30, relatively rust-prone parts shown as F4 part, F5 part, and F6 part in FIG. 1 and other parts are mixed. In the closed compressor 2 and the refrigeration cycle device 1 of the present embodiment, since the coating film 32 of the rust-prone portion is locally formed to be thick, it can be more reliably protected from rust. On the other hand, powder paint is not used in other parts than in rust-prone parts. Cost can be reduced because the coating film is formed in the required portion in the required amount.

In particular, in the closed compressor 2 and the refrigeration cycle device 1 of the present embodiment, the coating film 32b of the bottom portion 33 and the coating film 32c of the lid portion 34 are formed thicker than the coating film 32a of the body portion 35. Corrosion resistance can be further improved by further firmly covering the bottom portion 33 and the lid portion 34. The coating film 32d of the first and second welded portions 36 and 37 is formed thicker than the coating film 32a of the body portion 35. It is possible to further improve the corrosion resistance by further firmly covering the first and second welded portions 36 and 37 in which an oxide film or the like is formed by welding and the corrosion resistance tends to decrease. Further, since the refrigeration cycle device 1 of the present embodiment includes a sealed compressor 2 having both corrosion resistance and heat dissipation, it can be stably operated even in a harsh environment.

The present invention is not limited to the above-described embodiment as it is, and at the implementation stage, the components can be modified and embodied within a range that does not deviate from the gist thereof. In addition, various inventions can be formed by an appropriate combination of the plurality of components disclosed in the above-described embodiment. For example, some components may be removed from all the components shown in the embodiments. Further, the components of different embodiments may be combined as appropriate.

For example, the above-described embodiment has sufficient rust prevention properties without chemical conversion treatment, but chemical conversion treatment may be further added. Although the thickness of the coating film is controlled by the length of the spraying time, the thickness of the coating film may be controlled by another method. In order to increase the waviness of the coating film surface, the heating time of the powder coating material adhered to the substrate surface may be shortened. The particle size distribution of the powder coating material may be wider than usual.

1 ... Refrigeration cycle device, 2 ... Sealed compressor, 3 ... Dissipator, 4 ... Expander, 5 ... Evaporator, 23 ... Compression mechanism, 30 ... Sealed container, 32, 32a, 32b, 32c, 32d ... Coating Membrane, 33 ... bottom, 34 ... lid, 35 ... body, 36, 37 ... first and second welds.

Claims (2)

A compression mechanism that compresses the refrigerant,
A closed container containing the compression mechanism and
It is a sealed compressor equipped with
The closed container includes a bottom portion, a lid portion on the opposite side of the bottom portion, a body portion connecting the bottom portion and the lid portion, and a first welded portion in which the bottom portion and the body portion are joined by welding. A second welded portion in which the lid portion and the body portion are joined by welding is provided.
The closed container is configured to have a coating film having a locally changed thickness, and is also configured.
In the coating film formed on each of the bottom portion, the lid portion, and the body portion,
The coating film on the body has an arithmetic mean swell of 0.3 μm or more.
Based on the coating film on the body, the coating film on the bottom and the lid is 1.5 times thicker, and the coating film on the first welded portion and the second welded portion is 1.75 times thicker. A sealed compressor characterized by being formed in. The sealed compressor according to claim 1 and
A radiator connected to the closed compressor and
An expansion device connected to the radiator and
An evaporator connected between the inflator and the closed compressor,
Refrigeration cycle device equipped with.

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