JP7360785B2 - Rotary compressor and refrigeration cycle equipment - Google Patents

Description

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

A rotary compressor used in a refrigeration cycle device such as an air conditioner includes, for example, a horizontally elongated case, a compression mechanism section housed in the case, and an electric motor section that drives the compression mechanism section. The case stores lubricating oil. The compression mechanism compresses the working fluid.

In the rotary compressor, when lubricating oil is mixed into the working fluid, there is a possibility that the amount of lubricating oil discharged from the case together with the working fluid (discharged oil amount) increases. Furthermore, in the rotary compressor, the volume of the gas phase space may become smaller due to the lubricating oil level becoming higher in a part of the internal space of the case. Therefore, the separation of the lubricating oil from the working fluid may not progress, and the amount of lubricating oil discharged may further increase.

Patent No. 4261999 Japanese Patent Application Publication No. 2-264189

The problem to be solved by the present invention is to provide a rotary compressor and a refrigeration cycle device that can suppress the amount of lubricating oil discharged together with working fluid.

The rotary compressor of the embodiment includes a case, a compression mechanism section, an electric motor section, and a frame. The case stores lubricating oil. The case has a horizontally long shape. The compression mechanism section is housed within the case. The compression mechanism section compresses the working fluid. The electric motor section is connected to the compression mechanism section via a rotating shaft. The frame is provided within the case. The interior of the case is divided into a first chamber, a second chamber, and a third chamber. The first chamber is provided with a lubricating oil supply port that supplies the lubricating oil to the compression mechanism section, and a discharge port that discharges the working fluid discharged from the compression mechanism section to the outside of the case. There is. The second chamber is formed between the compression mechanism section and the electric motor section, and the working fluid is discharged from the compression mechanism section. The third chamber is formed on a side of the electric motor section opposite to the compression mechanism section. The rotary compressor supplies the working fluid between the first chamber and the second chamber, between the second chamber and the third chamber, and between the third chamber and the first chamber. It has a fluid flow path through which it circulates. The rotary compressor has a lubricating oil flow path that allows the lubricating oil to flow between the first chamber, the second chamber, and the third chamber. The frame partitions the first chamber and the second chamber. The lubricant flow path includes a first lubricant flow path and a second lubricant flow path. The first lubricating oil flow path is formed at a lower portion of the frame. The first lubricating oil flow path allows the lubricating oil to flow between the first chamber and the second chamber. The second lubricating oil flow path is formed at a lower portion of the electric motor section. The second lubricating oil flow path allows the lubricating oil to flow between the second chamber and the third chamber. The fluid flow path that allows the working fluid to flow between the second chamber and the third chamber is a second fluid flow path. The fluid flow path that allows the working fluid to flow between the third chamber and the first chamber is a third fluid flow path. The opening of the third fluid flow path on the third chamber side is closer to the central axis of the rotating shaft than the opening of the second fluid flow path on the third chamber side.

1 is a schematic configuration diagram of a refrigeration cycle device including a cross-sectional view of a rotary compressor according to a first embodiment. FIG. 2 is a schematic configuration diagram of a refrigeration cycle device including a cross-sectional view of a rotary compressor according to a second embodiment.

Hereinafter, a rotary compressor and a refrigeration cycle device according to an embodiment will be described with reference to the drawings.

(First embodiment)
As shown in FIG. 1, the refrigeration cycle device 100 of the first embodiment includes a rotary compressor 101, a radiator 102 (condenser), an expansion device 103, and a heat absorber 104 (evaporator). , these are connected by a refrigerant pipe 105. In the following description, the vertical direction will be defined based on FIG.

The rotary compressor 101 compresses a gas refrigerant, which is a working fluid. The radiator 102 condenses the high-pressure gas refrigerant discharged from the rotary compressor 101 into liquid refrigerant. The expansion device 103 reduces the pressure of the liquid refrigerant condensed in the radiator 102. The heat absorber 104 evaporates the liquid refrigerant whose pressure has been reduced by the expansion device 103.

The rotary compressor 101 includes a closed case 1 (case), a compression mechanism section 2 and an electric motor section 3 housed in the closed case 1, and a communication path 40. The closed case 1 is a case with a closed structure formed in a cylindrical shape. The sealed case 1 stores lubricating oil 16. The direction of the central axis C of the sealed case 1 is a direction intersecting the vertical direction (for example, a direction perpendicular to the vertical direction, that is, a horizontal direction). In the internal space of the sealed case 1, the horizontal length (the horizontal dimension in FIG. 1, i.e., the dimension in the direction of the central axis C) is larger than the height (the vertical dimension in FIG. 1, i.e., the inner diameter). It has a shape (horizontally long shape).

An insertion hole 43 is formed in the first end 1a (one end in the direction of the central axis C) of the sealed case 1. A discharge pipe 15 that discharges the gas refrigerant inside the sealed case 1 to the outside of the sealed case 1 is inserted through the insertion hole 43 . A discharge port 20, which is an inlet of the discharge pipe 15, is located in a first chamber 21, which will be described later. The sealed case 1 has a first end insertion hole 45 and a second end insertion hole 46 formed therein. A portion of the communication path 40 on the first end 40 a side is inserted into the first end insertion hole 45 . The first end insertion hole 45 is formed at a position facing the first chamber 21, which will be described later. A portion of the communication path 40 on the second end 40 b side is inserted into the second end insertion hole 46 . The second end insertion hole 46 is formed at a position facing the third chamber 23, which will be described later.

A frame 10 is provided inside the sealed case 1. The frame 10 is formed into a plate shape extending in a direction intersecting the central axis C of the closed case 1. The frame 10 is fixed to the inner peripheral surface of the sealed case 1.

A first fluid flow path 24A (fluid flow path) through which a gas refrigerant flows is formed in the upper part of the frame 10. The first fluid flow passage 24A penetrates the frame 10 in the thickness direction. The first fluid flow path 24A communicates a first chamber 21 and a second chamber 22, which will be described later. The first fluid flow path 24A allows gas refrigerant to flow between the first chamber 21 and the second chamber 22. The number of first fluid flow passages 24A may be one or more.

The distance between the opening 31 of the first fluid flow path 24A on the first chamber 21 side and the discharge port 20 of the discharge pipe 15 is greater than the distance between the opening 32 of the first end 40a of the communication path 40 and the discharge port 20. Preferably long. In other words, it is preferable that the opening 31 is further away from the discharge port 20 than the opening 32 is. According to this configuration, since the distance from the opening 31 to the discharge port 20 is long, the lubricating oil in the gas refrigerant flowing into the first chamber 21 from the second chamber 22 through the first fluid flow path 24A is transferred to the discharge port 20. It becomes easy to separate by the time it reaches . Therefore, the amount of lubricating oil discharged through the discharge pipe 15 can be suppressed.

A first lubricating oil flow path 25A (lubricating oil flow path) through which the lubricating oil 16 flows is formed in the lower part of the frame 10. The first lubricating oil flow passage 25A penetrates the frame 10 in the thickness direction. The first lubricating oil flow passage 25A communicates a first chamber 21 and a second chamber 22, which will be described later. The first lubricating oil flow path 25A allows the lubricating oil 16 to flow between the first chamber 21 and the second chamber 22. The number of first lubricating oil flow passages 25A may be one or more.

The compression mechanism section 2 includes a cylinder 6, bearings 7, 7, and a roller 9. The compression mechanism section 2 is provided inside the closed case 1. A cylinder chamber 5 is formed within the cylinder 6 by bearings 7, 7. A rotating shaft 4 passes through the cylinder chamber 5. The cylinder 6 is fixed to the frame 10 by screws or the like.

The bearings 7, 7 support the rotating shaft 4 at one end and the other end of the cylinder 6. Of the two bearings 7, 7, the bearing 7 on the motor section 3 side is the main bearing 7A, and the bearing 7 located at the opposite position from the main bearing 7A with respect to the cylinder 6 is the sub bearing 7B.

A discharge muffler 13 is provided on the main bearing 7A. The discharge muffler 13 is formed with a discharge hole 14 that opens into a second chamber 22, which will be described later.

The secondary bearing 7B is provided with a holding member 41 that holds the oil supply pipe 17. The lubricating oil supply port 19 , which is the inlet of the oil supply pipe 17 , is a suction port that sucks the lubricating oil 16 . The lubricating oil supply port 19 is located within the first chamber 21 . The lubricating oil supply port 19 is immersed in the lubricating oil 16 stored in the first chamber 21 .

The roller 9 is engaged with a crank eccentric portion 8 provided at a portion of the rotating shaft 4 located within the cylinder chamber 5 . When the rotating shaft 4 rotates, the roller 9 eccentrically rotates while contacting the inner circumferential surface of the cylinder 6 via a lubricating oil film.

The electric motor section 3 is provided inside the sealed case 1. The electric motor section 3 is located away from the compression mechanism section 2 in the direction along the central axis C (left-right direction in FIG. 1). The electric motor section 3 includes a rotor 28 and a stator 30. The rotor 28 is fixed to the rotating shaft 4. A portion of the rotating shaft 4 to which the rotor 28 is fixed is referred to as a shaft portion 29. The rotor 28 is provided with magnets (not shown). The rotor 28 rotates around the central axis 27 together with the rotating shaft 4 . The stator 30 is arranged at a position surrounding the rotor 28. A current-carrying coil is wound around the stator 30.

The rotating shaft 4 extends in a direction (eg, horizontal direction) that intersects with the vertical direction. The central axis 27 of the rotating shaft 4 coincides with the central axis C of the sealed case 1, for example. A portion of the rotating shaft 4 that is supported by the sub-bearing 7B is referred to as a first chamber-side shaft portion 26. For example, the first chamber side shaft portion 26 is a portion including the first end 4a. The first chamber side shaft portion 26 is located within the first chamber 21 .

The first end 4a (the end on the compression mechanism section 2 side) of the rotating shaft 4 may be in contact with a thrust plate (not shown) provided within the holding member 41. As will be described later, a force acts on the rotor 28 in a direction from the third chamber 23 toward the first chamber 21 along the central axis 27, but the movement of the rotating shaft 4 is restricted by the thrust plate. Ru.

The inside of the sealed case 1 is divided into a first chamber 21, a second chamber 22, and a third chamber 23.
The first chamber 21 is formed inside a portion of the sealed case 1 that includes the first end 1a. The first chamber 21 and the second chamber 22 are partitioned by the frame 10.

The second chamber 22 is formed between the compression mechanism section 2 and the electric motor section 3. The volume of the second chamber 22 is preferably smaller than the volume of the first chamber 21. It is preferable that the second chamber 22 has the smallest volume among the first chamber 21 to the third chamber 23. If the volume of the second chamber 22 is smaller than that of the first chamber 21, the influence of fluctuations in the oil level in the first chamber 21 on fluctuations in the oil level in the second chamber 22 can be reduced. Therefore, it is possible to suppress an increase in the amount of lubricating oil (oil discharge amount) discharged from the first chamber 21 through the discharge pipe 15 together with the gas refrigerant due to an increase in the oil level in the first chamber 21 . Further, the volume of the third chamber 23 can be increased, and the effect of separating lubricating oil within the third chamber 23 can be enhanced.

The third chamber 23 is formed on the opposite side of the motor section 3 from the compression mechanism section 2 side. The third chamber 23 is inside a portion of the sealed case 1 that includes the second end 1b (the other end in the direction of the central axis C).

A second fluid flow path 24B (fluid flow path) through which a gas refrigerant flows is formed in the upper part of the electric motor section 3. The second fluid flow path 24B has an inner circumference side flow path 24B1 and an outer circumference side flow path 24B2. The inner peripheral flow path 24B1 is formed in the rotor 28. The outer circumferential flow path 24B2 is formed in the stator 30. The openings of the inner circumferential flow path 24B1 and the outer circumferential flow path 24B2 on the third chamber 23 side are referred to as openings 34B1 and 34B2, respectively. The number of the inner circumference side flow path 24B1 and the outer circumference side flow path 24B2 may be one or more. The inner circumference side flow path 24B1 and the outer circumference side flow path 24B2 penetrate the electric motor section 3 in the direction along the rotating shaft 4, and communicate the second chamber 22 and the third chamber 23.

A second lubricating oil flow path 25B (lubricating oil flow path) through which the lubricating oil 16 flows is formed in the lower part of the electric motor section 3. The second lubricating oil flow passage 25B penetrates the electric motor section 3 in the direction along the rotating shaft 4, and communicates the second chamber 22 and the third chamber 23. The number of second lubricating oil flow passages 25B may be one or more.

The first lubricating oil flow passage 25A and the second lubricating oil flow passage 25B allow lubricating oil to flow between the first chamber 21, the second chamber 22, and the third chamber 23. Note that a lubricant flow path that communicates the first chamber 21 and the third chamber 23 may be provided instead of the second lubricant flow path 25B.

The communication path 40 is a conduit having a third fluid flow path 24C (fluid flow path) through which a gas refrigerant can flow. The third fluid flow path 24C communicates the third chamber 23 and the first chamber 21, and allows the gas refrigerant to flow between the third chamber 23 and the first chamber 21. A portion of the communication path 40 between a portion inserted into the first end insertion hole 45 and a portion inserted into the second end insertion hole 46 is provided outside the sealed case 1. The number of communication paths 40 may be one or more.

The opening 33 at the second end 40b of the communication path 40 is preferably closer to the central axis 27 of the rotating shaft 4 than the opening (openings 34B1, 34B2) on the third chamber 23 side of the second fluid flow path 24B. . When the opening 33 is closer to the central axis 27 of the rotating shaft 4 than the openings (openings 34B1, 34B2) of the second fluid flow path 24B, the gas introduced into the third chamber 23 from the second fluid flow path 24B is The lubricating oil contained in the refrigerant is easily separated from the gas refrigerant due to the centrifugal force generated by the rotation of the rotor 28. Therefore, the gas refrigerant introduced into the first chamber 21 from the opening 33 near the central axis 27 through the communication path 40 has a low lubricating oil content. Therefore, the amount of lubricating oil (oil discharge amount) discharged from the first chamber 21 through the discharge pipe 15 can be suppressed.

Let Pa be the pressure in the first chamber 21, Pb be the pressure in the second chamber 22, and Pc be the pressure in the third chamber 23. The cross-sectional area of the first chamber-side shaft portion 26 of the rotating shaft 4 perpendicular to the central axis 27 is defined as Aa. The first chamber-side shaft portion 26 is a portion of the rotating shaft 4 located within the first chamber 21 and supported by the sub-bearing 7B. Let Ar be the cross-sectional area of the rotor 28 of the electric motor section 3 perpendicular to the central axis 27. Let Aj be the cross-sectional area of the shaft portion 29 (the portion of the rotating shaft 4 to which the rotor 28 is fixed) perpendicular to the central axis 27.

The rotor 28 is provided so that its magnetic center is shifted toward the third chamber 23 with respect to the magnetic center of the stator 30. Therefore, a force is generated in the rotor 28 in a direction from the third chamber 23 side toward the first chamber 21 side. Let this force be F.
In the rotary compressor 101, it is preferable that the following relational expression (1) holds.

F+Pc×Aj-Pa×Aa>(Pb-Pc)×Ar...(1)

When relational expression (1) holds true, a thrust force can be applied to the rotating shaft 4 toward the first chamber 21, so that the rotating shaft 4 is in a state where its movement is restricted (for example, the first end 4a is in contact with the thrust plate). (state) can be maintained. Therefore, lubricating oil is efficiently supplied from the oil supply pipe 17 to the compression mechanism section 2. Therefore, the reliability of the operation of the compression mechanism section 2 can be improved. Further, when the relational expression (1) holds true, the movement of the rotating shaft 4 can be maintained in a restricted state, so that thrust noise can be suppressed. Therefore, it is possible to improve reliability and reduce noise.

In order for relational expression (1) to hold true, it is preferable to adjust one or more of the pressures Pa, Pb, and Pc to an appropriate range by setting the cross-sectional area of one or more of the fluid flow passages 24A to 24C.

Next, the operation of the rotary compressor 101 will be explained. As the gas refrigerant, carbon dioxide (CO ₂ ), HFC refrigerant (R410A, R32, etc.), HFO refrigerant (R1234yf, R1234ze, etc.), etc. can be used. Carbon dioxide as a gas refrigerant has a higher density than other gas refrigerants, so it is difficult to separate from lubricating oil. Since the rotary compressor 101 has excellent performance in separating gas refrigerant and lubricating oil, it tends to exhibit superiority when carbon dioxide is used as the gas refrigerant.

As the lubricating oil 16, for example, any one of ester-based, ether-based, alkylbenzene-based, and polyalkylene glycol-based oils, or a mixture of these oils can be used.

The rotating shaft 4 rotates around the central axis 27 by driving the electric motor section 3 . As the rotating shaft 4 rotates, the crank eccentric part 8 and the roller 9 rotate eccentrically within the cylinder chamber 5. At this time, the roller 9 comes into sliding contact with the inner peripheral surface of the cylinder 6. A gas refrigerant is drawn into the cylinder chamber 5 from outside the sealed case 1 through a suction pipe 11 . The gas refrigerant is compressed within the cylinder chamber 5.

The gas refrigerant compressed in the cylinder chamber 5 is introduced into the discharge muffler 13 from the discharge port 12 formed in the main bearing 7A. The gas refrigerant in the discharge muffler 13 is discharged into the second chamber 22 from the discharge hole 14 of the discharge muffler 13 .

A portion of the gas refrigerant in the second chamber 22 is introduced into the third chamber 23 through the second fluid flow path 24B. The gas refrigerant in the third chamber 23 is introduced into the communication path 40 from the opening 33. This gas refrigerant is introduced into the first chamber 21 from the opening 32 through the third fluid flow passage 24C. Another part of the gas refrigerant in the second chamber 22 is introduced into the first chamber 21 through the first fluid flow path 24A.

A part of the gas refrigerant in the first chamber 21 is introduced into the discharge pipe 15 from the discharge port 20 and is discharged to the outside of the sealed case 1 through the discharge pipe 15. The discharged gas refrigerant is introduced into the radiator 102.

The lubricating oil 16 in the first chamber 21 is supplied to each sliding portion from the oil supply pipe 17 via the inner cavity 18 of the rotating shaft 4 . The lubricating oil 16 can flow between the first chamber 21 and the second chamber 22 through the first lubricating oil flow path 25A. The lubricating oil 16 can flow between the second chamber 22 and the third chamber 23 through the second lubricating oil flow path 25B.

In the rotary compressor 101, a part of the gas refrigerant discharged from the compression mechanism section 2 into the second chamber 22 is introduced into the third chamber 23 through the second fluid flow path 24B, and lubricating oil is introduced into the third chamber 23. After being separated, it is introduced into the first chamber 21 through the third fluid flow path 24C. Therefore, the lubricating oil mixed in the gas refrigerant is more easily separated from the gas refrigerant than when the entire amount of the gas refrigerant is directly introduced into the first chamber 21 from the second chamber 22. Therefore, the amount of lubricating oil (oil discharge amount) discharged together with the gas refrigerant from the first chamber 21 through the discharge pipe 15 can be suppressed.

In the rotary compressor 101, a part of the gas refrigerant discharged into the second chamber 22 is introduced into the first chamber 21 via the third chamber 23, so that the first fluid flow is directly from the second chamber 22. The flow rate of the gas refrigerant introduced into the first chamber 21 through the passage 24A can be lowered. Therefore, separation of lubricating oil can proceed in this gas refrigerant. Therefore, the amount of lubricating oil (oil discharge amount) discharged through the discharge pipe 15 can be further suppressed.

In the rotary compressor 101, the gas refrigerant in the third chamber 23 is guided to the first chamber 21 by the third fluid flow path 24C, so the pressure in the third chamber 23 becomes low. Therefore, due to the pressure difference between the second chamber 22 and the third chamber 23, the oil level of the lubricating oil 16 in the third chamber 23 becomes high. This can prevent the oil level of the lubricating oil 16 in the first chamber 21 from becoming too high, increasing the volume of the gas phase space in the first chamber 21, making it easier to separate the lubricating oil and the gas refrigerant. Therefore, the amount of lubricating oil (oil discharge amount) discharged from the first chamber 21 through the discharge pipe 15 together with the gas refrigerant can be suppressed.

(Second embodiment)
A second embodiment will be described based on FIG. 2. Note that the same components as those described in the first embodiment are given the same reference numerals, and overlapping explanations will be omitted.

As shown in FIG. 2, the refrigeration cycle apparatus 200 of the second embodiment is different from the refrigeration cycle apparatus 100 of the first embodiment (see FIG. (see).

The rotary compressor 201 differs from the rotary compressor 101 (see FIG. 1) in that it includes a communication path 140 (fluid flow path) instead of the communication path 40. A fluid flow path 124A that constitutes a communication path 140 is formed in the frame 10. The fluid flow path 124A is a flow path that penetrates the frame 10 in the thickness direction. The fluid flow path 124A allows the first chamber 21 and the second chamber 22 to communicate with each other.

The communication path 140 includes a fluid flow path 124A, a third fluid flow path 124C in the pipe line 141, and a communication path 124D formed in the stator 30. The conduit 141 is provided inside the closed case 1. One end of the third fluid flow path 124C is connected to the communication path 124D. The communication path 140 is formed inside the sealed case 1. The communication path 140 allows the third chamber 23 and the first chamber 21 to communicate with each other, and allows gas refrigerant to flow between the third chamber 23 and the first chamber 21 . The number of communication paths 140 may be one or more.

The rotary compressor 201 is compact because the communication path 140 is provided inside the closed case 1. The rotary compressor 201 is easy to manufacture because the communication path 140 is provided inside the closed case 1.

According to at least one embodiment described above, a part of the working fluid discharged from the compression mechanism section into the second chamber is introduced into the third chamber, and then introduced into the first chamber through the fluid flow passage. . Therefore, compared to the case where the entire amount of the working fluid is directly introduced into the first chamber from the second chamber, the lubricating oil mixed in the working fluid is easily separated from the working fluid. Therefore, the amount of lubricating oil (oil discharge amount) discharged from the first chamber together with the working fluid can be suppressed.

Although several embodiments of the invention have been described, these embodiments are presented by way of example 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 changes can be made without departing from the gist of the invention. These embodiments and their modifications are included within the scope and gist of the invention as well as within the scope of the invention described in the claims and its equivalents.

DESCRIPTION OF SYMBOLS 1... Sealed case (case), 2... Compression mechanism section, 3... Electric motor section, 4... Rotating shaft, 14... Discharge hole, 16... Lubricating oil, 19... Lubricating oil supply port, 20... Discharge port, 21... First chamber, 22...second chamber, 23...third chamber, 24A...first fluid flow path (fluid flow path), 24B...second fluid flow path (fluid flow path), 24C...third fluid flow path (third 25A...first lubricating oil flow path (lubricating oil flow path), 25B...second lubricating oil flow path (lubricating oil flow path), 26... 1st chamber side shaft portion (portion located inside the first chamber), 28... Rotor, 29... Shaft portion (portion to which the rotor is fixed), 100, 200... Refrigeration cycle device, 101, 201... Rotary compression machine, 102...heat radiator, 103...expansion device, 104...heat absorber, 140...communication path (fluid flow path for circulating working fluid between the first chamber and the third chamber).

Claims (6)

An oblong case that stores lubricating oil,
a compression mechanism section that is housed in the case and compresses the working fluid;
an electric motor unit connected to the compression mechanism unit via a rotating shaft;
a frame provided within the case;
Equipped with
The inside of the case is
a first chamber provided with a lubricating oil supply port that supplies the lubricating oil to the compression mechanism section, and a discharge port that discharges the working fluid discharged from the compression mechanism section to the outside of the case;
a second chamber formed between the compression mechanism section and the electric motor section, from which the working fluid is discharged from the compression mechanism section;
a third chamber formed on a side of the electric motor section opposite to the compression mechanism section;
A fluid flow path for flowing the working fluid between the first chamber and the second chamber, between the second chamber and the third chamber, and between the third chamber and the first chamber, respectively. and a lubricating oil flow path for circulating the lubricating oil between the first chamber, the second chamber, and the third chamber,
the frame partitions the first chamber and the second chamber,
The lubricating oil flow path is
a first lubricating oil flow passage formed in a lower part of the frame and distributing the lubricating oil between the first chamber and the second chamber;
a second lubricating oil flow passage formed at a lower part of the electric motor section and distributing the lubricating oil between the second chamber and the third chamber ;
The fluid flow path that allows the working fluid to flow between the second chamber and the third chamber is a second fluid flow path,
The fluid flow path that allows the working fluid to flow between the third chamber and the first chamber is a third fluid flow path,
The opening of the third fluid flow path on the third chamber side is closer to the central axis of the rotating shaft than the opening of the second fluid flow path on the third chamber side.
Rotary compressor. The rotary compressor according to claim 1, wherein the fluid flow path that allows the working fluid to flow between the first chamber and the third chamber is provided within the case. The rotary compressor according to claim 1 or 2, wherein the volume of the second chamber is smaller than the volume of the first chamber. The electric motor section includes a stator and a rotor whose magnetic center is shifted toward the third chamber from the magnetic center of the stator,
The pressure in the first chamber is Pa, the pressure in the second chamber is Pb, the pressure in the third chamber is Pc, and a section perpendicular to the central axis of the portion of the rotating shaft located in the first chamber. The area is Aa, the cross-sectional area perpendicular to the central axis of the rotor is Ar, and the cross-sectional area perpendicular to the central axis of a portion of the rotating shaft to which the rotor of the motor section is fixed is Aj. , if F is the force acting on the rotor in the direction from the third chamber toward the first chamber due to the misalignment of the magnetic center of the rotor with respect to the stator, then the following relational expression (1) is obtained. The rotary compressor according to any one of claims 1 to 3, wherein:
F+Pc×Aj-Pa×Aa>(Pb-Pc)×Ar...(1) The rotary compressor according to any one of claims 1 to 4, wherein the working fluid is carbon dioxide. A rotary compressor according to any one of claims 1 to 5, a radiator connected to the rotary compressor, an expansion device connected to the radiator, and an expansion device connected to the expansion device. A refrigeration cycle device equipped with a heat absorber.

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