JP7604090B2 - Rotary compressor, manufacturing method thereof, and refrigeration cycle device - Google Patents

Description

Embodiments of the present invention relate to a multi-cylinder rotary compressor, a manufacturing method thereof, and a refrigeration cycle device equipped with the rotary compressor.

In recent years, in order to increase the refrigerant compression capacity, a vertical three-cylinder rotary compressor has been developed that has a compression mechanism in which three sets of refrigerant compression units are arranged in the axial direction of the rotary shaft. This type of rotary compressor has a longer overall length of the rotary shaft and a larger height of the compression mechanism, compared to a two-cylinder rotary compressor in which two sets of refrigerant compression units are arranged in the axial direction of the rotary shaft.
Furthermore, since the number of refrigerant compression sections is greater than in a two-cylinder rotary compressor, the output of the electric motor must be increased, which inevitably leads to an increase in the size of the electric motor.

Patent No. 4594302 Japanese Patent Application Publication No. 6-26478

In a three-cylinder rotary compressor, a heavy and large electric motor protrudes above the compression mechanism, which has an increased height, and the overall height of the sealed container housing the compression mechanism and the electric motor increases. This naturally increases the center of gravity of the three-cylinder rotary compressor, which creates a risk of large vibrations during operation. In order to reduce vibrations, it is possible to increase the number of fixing parts that fix the compression mechanism to the sealed container, but the compressor is generally welded to the sealed container by arc spot welding, which requires pilot holes to be drilled for welding, and the increased number of pilot holes may lead to manufacturing defects such as poor airtightness.
An object of the present invention is to provide a highly reliable rotary compressor which reduces vibration and noise during operation and which suppresses manufacturing defects.

In order to achieve the above object, the rotary compressor of the embodiment includes a cylindrical sealed container, a compression mechanism unit having a rotating shaft and a plurality of refrigerant compression units arranged in the sealed container at intervals in the axial direction of the rotating shaft and compressing a refrigerant, a stator fixed to the inner peripheral surface of the sealed container above the compression mechanism unit, and a rotor surrounded by the stator and fixed to the rotating shaft, and an electric motor that drives the compression mechanism unit via the rotating shaft inside the sealed container, and an accumulator that is connected to the compression mechanism unit via a suction pipe and separates the refrigerant into a liquid phase refrigerant and a gas phase refrigerant. The compression mechanism unit is welded to the sealed container by a main fixing part and an auxiliary fixing part located below the main fixing part. The number of welding points between the main fixing part and the sealed container is greater than the number of welding points between the auxiliary fixing part and the sealed container, and the main fixing part is composed of a main support member to which the refrigerant compression unit closest to the electric motor is connected, and the auxiliary fixing part is composed of an auxiliary support member to which the refrigerant compression unit farthest from the electric motor is connected. The multiple welding points of the main fixing part are provided at positions where the angle between a line connecting the welding points and the central axis of the sealed container and a straight-line reference line connecting the central axis of the sealed container and the central axis of the accumulator is 30° to 50°, at positions where the angle between the line connecting the welding points and the central axis of the sealed container and the reference line is 20° to 30°, and at positions where the angle between the line connecting the welding points and the central axis of the sealed container and the straight-line reference line and a line perpendicular to the straight-line reference line is 0° to 10°, and the axial distance from the multiple welding points of the main fixing part to the center of gravity of a structure including the compression mechanism and the rotor of the electric motor is closer than the axial distance from the welding points of the auxiliary fixing part to the center of gravity.

1 is a schematic configuration diagram of a refrigeration cycle device according to a first embodiment. FIG. 2 is a vertical cross-sectional view of the rotary compressor according to the embodiment. FIG. 2 is a plan view of the cylinder according to the embodiment. FIG. 2 is a plan view of the rotary compressor according to the embodiment. FIG. 11 is a longitudinal sectional view of a main portion of a rotary compressor according to a second embodiment.

Hereinafter, an embodiment for carrying out the invention will be described.
(First embodiment)
A rotary compressor according to a first embodiment will be described with reference to Fig. 1 to Fig. 4. Fig. 1 shows the configuration of a refrigeration cycle of an air conditioner 1, which is, for example, a refrigeration cycle device. The air conditioner 1 includes a rotary compressor 2, a four-way valve 3, an outdoor heat exchanger 4, an expansion device 5, and an indoor heat exchanger 6. These are connected via a refrigerant passage 7 through which a refrigerant circulates.

Specifically, as shown in FIG. 1, the discharge side of the rotary compressor 2 is connected to a first port 3a of the four-way valve 3. The second port 3b of the four-way valve 3 is connected to an outdoor heat exchanger 4. The outdoor heat exchanger 4 is connected to an indoor heat exchanger 6 via an expansion device 5. The indoor heat exchanger 6 is connected to the suction side of the rotary compressor 2 via an accumulator 8. When the air conditioning device 1 performs cooling operation, the four-way valve 3 switches so that the first port 3a communicates with the second port 3b and the third port 3c communicates with the fourth port 3d.

When the air conditioning device 1 starts cooling operation, the high-temperature, high-pressure gas-phase refrigerant compressed by the rotary compressor 2 is guided to the outdoor heat exchanger 4, which functions as a radiator (condenser), via the four-way valve 3. The gas-phase refrigerant guided to the outdoor heat exchanger 4 condenses through heat exchange with the outside air and changes to a high-pressure two-phase gas-liquid refrigerant. The high-pressure two-phase gas-liquid refrigerant is reduced in pressure as it passes through the expansion device 5 and changes to a low-pressure two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant is guided to the indoor heat exchanger 6, which functions as a heat absorber (evaporator), and exchanges heat with the indoor air as it passes through the indoor heat exchanger. As a result, the two-phase gas-liquid refrigerant absorbs heat from the air and evaporates, changing to a low-temperature, low-pressure gas-phase refrigerant. The air passing through the indoor heat exchanger 6 is cooled by the latent heat of evaporation of the liquid-phase refrigerant and is sent into the room as cold air. The low-temperature, low-pressure gas-phase refrigerant that has passed through the indoor heat exchanger 6 is guided to the accumulator 7 via the four-way valve 3. If the refrigerant contains liquid-phase refrigerant that has not completely evaporated, it is separated into liquid-phase refrigerant and gas-phase refrigerant in the accumulator 7. The low-temperature, low-pressure gas-phase refrigerant from which the liquid-phase refrigerant has been separated is sucked into the rotary compressor 2, where it is compressed again into high-temperature, high-pressure gas-phase refrigerant, repeating the above cycle.

When the air conditioning device 1 starts heating operation, the four-way valve 3 switches so that the first port 3a is connected to the third port 3c and the second port 3b is connected to the fourth port 3d. Therefore, the high-temperature, high-pressure gas-phase refrigerant discharged from the rotary compressor 2 is guided to the indoor heat exchanger 6 functioning as a condenser via the four-way valve 3, and is heat exchanged with the indoor air passing through the indoor heat exchanger 6. As a result, the gas-phase refrigerant passing through the indoor heat exchanger 6 is condensed by heat exchange with the air and changes to a high-pressure gas-phase refrigerant. The air passing through the indoor heat exchanger 6 is heated by heat exchange with the gas-phase refrigerant and sent into the room as hot air. The high-temperature liquid-phase refrigerant that has passed through the indoor heat exchanger 6 is guided to the expansion device 5 and is decompressed by the expansion device 5 to change to a low-pressure gas-liquid two-phase refrigerant. The gas-liquid two-phase refrigerant is guided to the outdoor heat exchanger 4, which functions as an evaporator, and evaporates by exchanging heat with the outdoor air, changing into a low-temperature, low-pressure gas-phase refrigerant. The low-temperature, low-pressure gas-phase refrigerant that has passed through the outdoor heat exchanger 4 is sucked into the rotary compressor 2 via the four-way valve 3 and the accumulator 8.

Next, a specific configuration of the rotary compressor 2 used in the air-conditioning apparatus 1 will be described. Fig. 2 is a diagram showing the internal structure of the vertical three-cylinder rotary compressor 2. As shown in Fig. 2, the rotary compressor 2 includes an airtight container 10, and an electric motor 11 and a compression mechanism 12 inside the airtight container 10.

The sealed container 10 is composed of three components, for example, a container body 10a, a bottom member 10b, and a lid member 10c. The container body 10a has a cylindrical peripheral wall 10d and stands upright along the vertical direction. The bottom member 10b is welded to the bottom end of the container body 10a so as to close the bottom opening of the container body 10a. The lid member 10c is welded to the top end of the container body 10a so as to close the top opening of the container body 10a.

A discharge pipe 10e is attached to the cover member 10c. The discharge pipe 10e is connected to the first discharge port 3a of the four-way valve 3 via the refrigerant circuit 7.
Lubricating oil for lubricating the compression mechanism 12 is stored in the lower part of the sealed container 10 .

The electric motor 11 is an inner rotor type motor and includes a stator 13 and a rotor 14. The stator 13 is fixed to the inner surface of the peripheral wall 10d of the vessel body 10a by shrink fitting or the like. The rotor 14 is positioned coaxially with the central axis O1 of the sealed vessel 10 (the central axis of the rotary compressor 2 ) and is surrounded by the stator 13.

The compression mechanism 12 includes a first refrigerant compression section 15A, a second refrigerant compression section 15B, a third refrigerant compression section 15C, a first intermediate partition plate 16, a second intermediate partition plate 17, a main bearing 18, an auxiliary bearing 19, and a rotating shaft 20. The center of gravity G of the structure including the compression mechanism 12 and the rotor 14 of the electric motor 11 that constitute the rotary compressor 2 of this embodiment is shown in Figure 2.

The rotating shaft 20 is positioned coaxially with the central axis O1 of the sealed container 10. The rotating shaft 20 has an upper end fixed to the rotor 14 of the electric motor 11, and first to third crank portions 40a, 40b, 40c formed integrally with the rotating shaft 20 at a distance from each other on the compression mechanism 12 side.
The first to third crank portions 40 a , 40 b , 40 c are eccentric with respect to the center of rotation of the rotating shaft 20 , and the eccentric directions are shifted by 120° in the circumferential direction of the rotating shaft 20 .

The first to third refrigerant compression sections 15A, 15B, and 15C are arranged in a row at intervals in the axial direction of the sealed container 10 and are arranged to surround the first to third crank sections 40a, 40b, and 40c of the rotating shaft 20, respectively. The first to third refrigerant compression sections 15A, 15B, and 15C each include a first cylinder body 21a, a second cylinder body 21b, and a third cylinder body 21c.

The first intermediate partition plate 16 is interposed between the first cylinder body 21a and the second cylinder body 21b. The upper surface of the first intermediate partition plate 16 is superimposed on the lower surface of the first cylinder body 21a so as to cover the inner diameter portion of the first cylinder body 21a from below, and the lower surface of the first intermediate partition plate 16 is superimposed on the upper surface of the second cylinder body 21b so as to cover the inner diameter portion of the second cylinder body 21b from above.
The second intermediate partition plate 17 is interposed between the second cylinder body 21b and the third cylinder body 21c. The upper surface of the second intermediate partition plate 17 is overlapped with the lower surface of the second cylinder body 21b so as to cover the inner diameter portion of the second cylinder body 21b from below. The lower surface of the second intermediate partition plate 17 is overlapped with the upper surface of the third cylinder body 21c so as to cover the inner diameter portion of the third cylinder body 21c from above.

The main bearing 18 is disposed on the upper surface of the first cylinder body 21a. The main bearing 18 has a flange portion 23 that protrudes toward the peripheral wall 10d of the container body 10a. The flange portion 23 is overlapped on the upper surface of the first cylinder body 21a so as to cover the inner diameter portion of the first cylinder body 21a from above. A first muffler 31 is attached to the end face of the main bearing 18 on the electric motor 11 side, and a first muffler chamber 32 is formed inside the first muffler 31.

The secondary bearing 19 is disposed on the underside of the third cylinder body 21c. The secondary bearing 19 has a flange portion 29 that protrudes toward the peripheral wall 10d of the container body 10a. The flange portion 29 is superimposed on the underside of the third cylinder body 21c so as to cover the inner diameter portion of the third cylinder body 21c from below. A second muffler chamber 33 is attached to the end face of the secondary bearing 19 opposite the electric motor 11, and a second muffler chamber 34 is formed inside the second muffler chamber 33.

The flange portion 23 of the main bearing 18, the first cylinder body 21a, the first intermediate partition plate 16, and the second cylinder body 21b are stacked in the axial direction of the sealed container 10 and are integrally connected via a plurality of first fastening bolts 24.

The flange portion 29 of the auxiliary bearing 19, the third cylinder body 21c, the second intermediate partition plate 17 and the second cylinder body 21b are stacked in the axial direction of the sealed container 10 and are integrally connected via a plurality of second fastening bolts 28.

The first cylinder body 21 a forms a first cylinder chamber 25 in a region surrounded by the flange portion 23 of the main bearing 18 and the first intermediate partition plate 16 .
The second cylinder body 21 b forms a second cylinder chamber in a region surrounded by the first intermediate partition plate 16 and the second intermediate partition plate 17 .
The third cylinder body 21 c defines a third cylinder chamber 27 in a region surrounded by the second intermediate partition plate 17 and the flange portion 29 of the auxiliary bearing 19 .

The first to third cylinder chambers 25, 26, 27 are fitted with the first to third crank portions 40a, 40b, 40c of the rotating shaft 20 and have the first to third rollers 41a, 41b, 41c that rotate eccentrically.

As shown in FIG. 3 as a representative example of the first cylinder body 21a, a vane slot 42 is formed in each of the first to third cylinder bodies 21a, 21b, and 21c so as to extend in the radial direction of the first cylinder chamber 25.
A vane 43 is housed in the vane slot 42. The vane 43 is movable along the vane slot 42 in the radial direction of the first cylinder chamber 25 and is biased toward the first cylinder chamber 25 via a spring 44. A tip of the vane 43 is slidably pressed against an outer circumferential surface of a roller 41a. The vane 43 cooperates with the roller 41a to divide the first cylinder chamber 25 into a suction region R1 and a compression region R2.

As shown in FIG. 2, the container body 10a has an opening 45. The first to third cylinder bodies 21a, 21b, and 21c have suction ports 46 that open into the cylinder chambers 25, 26, and 27, and the first to third suction pipes 36, 37, and 38 that extend from the lower end of the accumulator 8 are connected through the opening 45.

The flange portion 23 of the main bearing 18 and the first intermediate partition plate 16 are provided with a discharge valve (not shown) that opens the discharge hole when the pressure in the discharge hole and in the compression region R2 of the first cylinder chamber 25 reaches a predetermined value.
The first intermediate partition plate 16 and the second intermediate partition plate 17 are provided with a discharge hole and a discharge valve that opens the discharge hole when the pressure in the compression region R2 of the second cylinder chamber 26 reaches a predetermined value.
The second intermediate partition plate 17 and the flange portion 29 of the auxiliary bearing 19 are provided with a discharge hole and a discharge valve that opens the discharge hole when the pressure in the compression region R2 of the third cylinder chamber 27 reaches a predetermined value.

The discharge side of the discharge valve of the main bearing 18 communicates with the first muffler chamber 32, and the discharge side of the discharge valve of the sub-bearing 19 communicates with the second muffler chamber 34. The second muffler chamber 34 communicates with the first muffler chamber 32 via a discharge passage (not shown).
The discharge side of the discharge valve of the first intermediate partition plate 16 and the discharge side of the discharge valve of the second intermediate partition plate 17 communicate with the above-mentioned discharge passage and also communicate with the first muffler chamber 32 .

The above-mentioned compression mechanism 12 has an upper end fixed to the container body 10 a by a main support member 63 , and a lower end fixed to the container body 10 a by an auxiliary support member 64 .
The main support member 63 is disposed on the upper surface of the first cylinder body 21a, on the outer circumferential side of the flange portion 23 of the main bearing 18. The main support member 63 and the first cylinder body 21a are fastened to each other by a plurality of third fastening bolts 30.
The auxiliary support member 64 is disposed on the lower surface of the third cylinder body 21c on the outer circumferential side of the flange portion 23 of the auxiliary bearing 19. The auxiliary support member 64 and the third cylinder body 21c are fastened to each other by a plurality of fourth fastening bolts 35.

The main support member 63 and the auxiliary support member 64 are welded to a predetermined position of the container body 10a. For example, the main support member 63 is welded at the position of six pilot holes formed at the same height in the circumferential direction of the sealed container 10. The auxiliary support member 64 is welded at the position of three pilot holes formed at the same height in the circumferential direction of the container body 10a. The welding point of the main support member 63 and the container body 10a is called a welding point 65, and the welding point of the auxiliary support member 64 and the container body 10a is called a welding point 66. The main support member 63 constitutes the main fixing part 61 that fixes the upper end of the compression mechanism part 12 to the container body 10a. The welding point 65 of the main fixing part 61 has a distance T1 to the center of gravity G. The auxiliary support member 64 constitutes the auxiliary fixing part 62 that fixes the lower end of the compression mechanism part 12 to the container body 10a. The welding point 66 of the auxiliary fixing part 62 has a distance T2 to the center of gravity G. In this embodiment, the distance T1 from the welding point 65 of the main fixing part 61 to the center of gravity G is closer than the distance T2 from the welding point 66 of the auxiliary fixing part 62 to the center of gravity G.

4 is a plan view of the rotary compressor 2 showing the positions of the welding points 65 and 66. A part of the welding point 65 is provided at the same position in the circumferential direction of the sealed container 10 as the welding point 66. In this embodiment, the welding points 65 are six points in total, including two points 65a and 65b that sandwich a fixed part of the accumulator 8, two points 65c and 65d on the opposite side of the accumulator 8, one point 65e between the welding points 65a and 65c, and one point 65f between the welding points 65b and 65d .

In detail, the welding point 65a is provided at a position where the angle θ1 formed by the line connecting the welding point 65a and the central axis O1 of the rotary compressor 2 and the line connecting the central axis O1 of the rotary compressor 2 and the central axis O2 of the accumulator 8 (hereinafter referred to as the reference line A) is 30° to 50°. Similarly, the welding point 65b is provided at a position where the angle θ2 formed by the line connecting the welding point 65b and the central axis O1 of the rotary compressor 2 and the reference line A is 30° to 50°. At this time, the welding points 65a and 65b are provided on opposite sides of the reference line A.
The welding points 65c and 65d are provided at positions where angles θ3 and θ4 formed by a line connecting the welding points 65c and 65d with the central axis O1 of the rotary compressor 2 and the reference line A are 20° to 30°. At this time, the welding points 65c and 65d are provided on opposite sides of the reference line A.
The welding points 65e and 65f are provided at positions where angles θ5 and θ6 formed by a line connecting each welding point 65e, 65f with the central axis O1 of the rotary compressor 2 and a line perpendicular to the reference line A are 0° to 10°. The welding points 65e and 65f are provided at positions facing each other.

The welding points 66 are provided at the same positions as any three of the welding points 65, for example, welding points 65a, 65c, and 65f. By providing the welding points 65 and 66 at the above positions, the compression mechanism 12 can be stably supported without interfering with the fixing of the accumulator 8 to the sealed container 10.

Next, a method for manufacturing the above-mentioned three-cylinder rotary compressor 2 will be described.
The vessel body 10a is provided with pilot holes at positions where the main support member 63 and the auxiliary support member 64 are to be welded. The main support member 63 is inserted to a predetermined position and welded and fixed to the vessel body 10a by arc spot welding through the pilot holes.
Next, for example, the container body 10a is heated and the stator 13 of the motor 11 is fixed to the container body 10a on the upper side of the main support member 63 by shrink fitting.

Meanwhile, the rotor 14 of the electric motor 11 is fixed to the rotating shaft 20 of the compression mechanism 12, which includes the auxiliary support member 64. In this state, the compression mechanism 12 is inserted into the container body 10a. At this time, the container body 10a is turned upside down so that the stator 13 is at the bottom, and the rotating shaft 20 is inserted downward from the rotor 14 side until the top surface of the first cylinder body 21a of the compression mechanism 12 abuts against the main support member 63. Make sure that the suction port 46 of the compression mechanism 12 faces the opening 45 of the container body 10a.

In this state, the main support member 63 and the first cylinder body 21a are fastened together with the third fastening bolt 30, and the auxiliary support member 64 and the third cylinder body 21c are temporarily fastened together with the fourth fastening bolt 35. The auxiliary support member 64 is welded and fixed by arc spot welding through a pilot hole in the container body 10a. The auxiliary support member 64 temporarily fastened together with the fourth fastening bolt 35 and the third cylinder body 21c are then fully fastened together. The bottom member 10b and the lid member 10c are then welded and fixed to the container body 10a.

In such a three-cylinder rotary compressor 2, when the electric motor 11 is driven, the first to third rollers 41a, 41b, and 41c of the compression mechanism 12 rotate eccentrically in accordance with the rotation of the rotating shaft 20. This changes the volume of the suction region R1 and compression region R2 of the first to third cylinder chambers 25, 26, and 27, and the gas-phase refrigerant is sucked from the accumulator 8 through the first to third suction pipes 36, 37, and 38 into the suction region R1 of the first to third cylinder chambers 25, 26, and 27 through the suction port 46.

The gas-phase refrigerant sucked into the suction region R1 of the first cylinder chamber 25 from the first suction pipe 36 is gradually compressed as the suction region R1 transitions to the compression region R2, and when the pressure in the compression region R2 reaches a predetermined value, the discharge valve opens and the gas-phase refrigerant compressed in the first cylinder chamber 25 is discharged into the first muffler chamber 32 through the main bearing 18 and the first intermediate partition plate 16.
The gas-phase refrigerant sucked into the suction region R1 of the second cylinder chamber 26 from the second suction pipe 37 is compressed, and when the pressure in the compression region R2 reaches a predetermined value, the discharge valve opens and the refrigerant is guided to the first muffler chamber 32 via the first intermediate partition plate 16 and the second intermediate partition plate 17.
The gas-phase refrigerant sucked into the suction region R1 of the third cylinder chamber 27 from the third suction pipe 38 is compressed, and when the pressure in the compression region R2 reaches a predetermined value, the discharge valve opens and the refrigerant is guided to the first muffler chamber 32 via the second intermediate partition plate 17 and the second muffler chamber 34.

The eccentric directions of the first to third crank portions 40a, 40b, and 40c of the rotating shaft 20 are shifted by 120° each in the circumferential direction of the rotating shaft 20. Therefore, there is an equivalent phase difference in the timing at which the gas-phase refrigerant compressed in the first to third cylinder chambers 25, 26, and 27 is discharged.
The gas-phase refrigerant compressed in the first to third cylinder chambers 25, 26, 27 join together in the first muffler chamber 32 and is continuously discharged from the exhaust hole of the first muffler 31 into the sealed container 10. The gas-phase refrigerant discharged into the sealed container 10 passes through the electric motor 11 and is then guided to the four-way valve 3 from the discharge pipe 10e.

In the rotary compressor 2 of this embodiment, the upper end side of the compression mechanism 12 is fixed to the sealed container 10 by the main fixing part 61, and the lower end side of the compression mechanism 12 is fixed to the sealed container 10 by the auxiliary fixing part 62. In this embodiment, the center of gravity G of the structure including the rotor 14 of the electric motor 11 and the compression mechanism 12 is located between the first crank part 40a and the second crank part 40b. Therefore, the distance T1 from the main support member 63 to the center of gravity G is closer than the distance T2 from the auxiliary support member 64 to the center of gravity G. On the other hand, the welding points 65 of the main fixing part 61 are provided more than the welding points 66 of the auxiliary fixing part 62. Therefore, the vicinity of the center of gravity G, which is a vibration element of the compression mechanism 12, can be firmly fixed to the sealed container 10, and the vibration of the compression mechanism 12 can be suppressed.

Furthermore, by fixing the lower end of the compression mechanism unit 12 with the auxiliary fixing part 62, vibration of the compression mechanism unit 12 can be suppressed, and by reducing the number of welding points 66, the amount of pilot hole processing can be reduced, thereby preventing manufacturing defects such as poor airtightness.
Moreover, the auxiliary fixing portion 62 may be fixed by laser welding. In this case, since pilot hole processing is not required, it is possible to prevent the occurrence of welding defects and airtightness defects, and it is easy to ensure pressure resistance.

Second Embodiment
5 shows the compression mechanism 12 of the rotary compressor 2 of the second embodiment. The second embodiment differs from the first embodiment in the configuration for fixing the lower end side of the compression mechanism 12 to the sealed container 10. The second embodiment does not include the auxiliary support member 64, and the third cylinder body 21c constitutes the auxiliary fixing portion 62. Therefore, the outer periphery of the third cylinder body 21c is in contact with the sealed container 10.

The container body 10a has a plurality of welding points 65 at the same circumferential height corresponding to the main support member 63, and the third cylinder body 21c has fewer welding points 66 at the same circumferential height corresponding to the main support member 63. The number of pilot holes formed in the container body 10a for fixing the third cylinder body 21c is fewer than the number of pilot holes for fixing the main support member 63. With this configuration, the auxiliary support member 64 is not necessary, and the number of parts of the auxiliary fixing portion 62 can be reduced.

According to at least one embodiment of the three-cylinder rotary compressor 2 described above, the compression mechanism unit 12 is firmly fixed by having more welding points 65 of the main fixing part 61 close to the center of gravity G of the rotary compressor 2, which is the vibrating element, than the welding points 66 of the auxiliary fixing part 62 away from the center of gravity G, thereby making it possible to suppress vibration of the compression mechanism unit 12 and to prevent manufacturing defects such as poor airtightness due to pilot hole processing for welding.
Furthermore, if the auxiliary fixing portion 62 is welded by laser welding, pilot hole drilling is not required, making it possible to prevent manufacturing defects and ensure the pressure resistance of the sealed container 10 .

The main fixing part 61 is composed of a main support member 63 connected to the first refrigerant compression part 15A of the compression mechanism part 12, and the auxiliary fixing part 62 is composed of an auxiliary support member 64 connected to the third refrigerant compression part 15C. In the manufacturing method of the rotary compressor 2, the main support member 63 is welded and fixed to the container body 10a in advance, and the compression mechanism part 12 including the auxiliary support member 64 and having the rotor 14 of the electric motor 11 attached thereto is inserted into the container body 10a. Next, the main support member 63 and the first refrigerant compression part 15A are connected using the third fastening bolt 30, and the auxiliary support part 64 is welded and fixed to the sealed container 10, so that the compression mechanism part 12 can be easily positioned and fixed.

In the above embodiment, a three-cylinder rotary compressor having a compression mechanism 12 in which three sets of refrigerant compression sections 15 are arranged in the axial direction of the rotating shaft 20 is described, but the present invention can also be applied to a two-cylinder rotary compressor in which two sets of refrigerant compression sections 15 are arranged in the axial direction of the rotating shaft 20.

Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope of the invention and its equivalents as described in the claims, as well as in the scope and gist of the invention.

1...air conditioner, 2...rotary compressor, 4...outdoor heat exchanger, 5...expansion device, 6...indoor heat exchanger, 10...sealed container, 11...motor, 12...compression mechanism, 13...stator, 14...rotor, 15A...first refrigerant compression section, 15B...second refrigerant compression section, 15C...third refrigerant compression section, 20...rotating shaft, 61...main fixing section, 62...auxiliary fixing section, 63...main support member, 64...auxiliary support member, 65, 65...welding point, G...center of gravity, T1...distance from main fixing section to center of gravity G, T2...distance from auxiliary fixing section to center of gravity G

Claims (5)

A cylindrical sealed container;
a compression mechanism unit including a rotating shaft and a plurality of refrigerant compression units arranged in the sealed container at intervals in an axial direction of the rotating shaft and configured to compress a refrigerant;
an electric motor including a stator fixed to an inner peripheral surface of the sealed container above the compression mechanism and a rotor surrounded by the stator and fixed to the rotating shaft, the electric motor driving the compression mechanism via the rotating shaft inside the sealed container;
an accumulator connected to the compression mechanism via a suction pipe and separating the refrigerant into a liquid phase refrigerant and a gas phase refrigerant;
The compression mechanism is fixed to the sealed container by welding at a main fixing part and an auxiliary fixing part located below the main fixing part,
the number of welding points between the main fixing portion and the sealed container is greater than the number of welding points between the auxiliary fixing portion and the sealed container,
the main fixing part is constituted by a main support member to which the refrigerant compression part closest to the electric motor is connected, and the auxiliary fixing part is constituted by an auxiliary support member to which the refrigerant compression part farthest from the electric motor is connected,
the multiple welding points of the main fixing portion are provided at positions where an angle between a line connecting the welding points and a central axis of the sealed container and a linear reference line connecting the central axis of the sealed container and a central axis of the accumulator is 30° to 50°, at positions where an angle between the line connecting the welding points and the central axis of the sealed container and the reference line is 20° to 30°, and at positions where an angle between the line connecting the welding points and the central axis of the sealed container and the reference line is 0° to 10°,
a welding point of the auxiliary fixing portion for welding the compression mechanism to the rotor of the electric motor in an axial direction, the welding point being located in the axial direction of the auxiliary fixing portion; The rotary compressor according to claim 1, wherein the compression mechanism has first to third refrigerant compression sections. a circulation circuit in which a refrigerant circulates and which is connected to a radiator, an expansion device, and a heat sink;
3. A refrigeration cycle apparatus comprising: the rotary compressor according to claim 1 or 2, connected to the circulation circuit between the radiator and the heat sink. a compression mechanism portion fixed to an inner circumferential wall of a sealed container and having first to third refrigerant compression portions which compress a refrigerant; and an electric motor having a stator and a rotor and driving the compression mechanism portion via a rotating shaft, the compression mechanism portion being welded and fixed to the sealed container by a main fixing portion and an auxiliary fixing portion, the main fixing portion being constituted by a main support member to which the first refrigerant compression portion closest to the electric motor is connected, a number of welding points between the main fixing portion and the sealed container are greater than the number of welding points between the auxiliary fixing portion and the sealed container , the auxiliary fixing portion being constituted by an auxiliary support member attached to the compression mechanism portion below the main fixing portion, and the distance from the auxiliary fixing portion to a center of gravity of a structure including the compression mechanism portion and the rotor of the electric motor is greater than a distance to the center of gravity of the main fixing portion,
welding the main support member to the sealed container;
inserting the compression mechanism into the sealed container and fixing the first refrigerant compression unit to the main support member;
and welding the auxiliary support member to the sealed container. The method for manufacturing a rotary compressor according to claim 4, wherein the auxiliary support member is welded to the sealed container by laser welding.

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