EP3434902B1

EP3434902B1 - Hermetic rotary compressor and refrigeration cycle device

Info

Publication number: EP3434902B1
Application number: EP17770180.2A
Authority: EP
Inventors: Takuya Hirayama; FERDHY Monasry JAFET; Shinya Goto
Original assignee: Toshiba Carrier Corp
Current assignee: Toshiba Carrier Corp
Priority date: 2016-03-25
Filing date: 2017-03-17
Publication date: 2020-10-07
Anticipated expiration: 2037-03-17
Also published as: JP6574519B2; WO2017164138A1; JPWO2017164138A1; CN109072916B; CN109072916A; EP3434902A1; EP3434902A4

Description

Technical Field

Embodiments described herein relate generally to a hermetic rotary compressor and refrigeration cycle device provided with the hermetic rotary compressor.

Background Art

A hermetic rotary compressor is provided with a hermetic case configured to accommodate therein an electric motor section and compression mechanism section. The hermetic case is constituted of, for example, a cylindrical main case and lid-like end cases, and the end cases having an identical diameter are fitted into both ends of the main case to thereby hermetically seal the hermetic case. In FIG. 1 of Patent Literature 1, a rotary compressor in which a hermetic case is hermetically sealed by inserting end cases having diameters smaller than an inner diameter of a main case into both ends of the main case is disclosed. A cylinder disclosed in Patent Literature 1 is formed smaller than an inner diameter of the end case.
JP H11 336682 A discloses a rotary compression mechanism with a helical blade. Rotation is transmitted to a roller by a rotating shaft. A blade inserted inside a helical groove is abutted against the roller, partitioning the compression chamber. In FIG. 7, a two stage compressor with two compression chambers is disclosed.
WO 2009/064042 A1 discloses a two stage rotary compressor including a low pressure compression assembly, a middle plate and a high pressure compression assembly.
CN 104 632 581 A discloses a two stage compressor comprising a housing with an upper and a lower cover, wherein an outlet pipe is connected with the upper cover.
In recent years, a carbon dioxide refrigerant has been brought into use as a working fluid of a refrigeration cycle device. A carbon dioxide refrigerant has working pressure higher than a hitherto used HFC-based refrigerant, and hence it is necessary to enhance the pressure resistance of the hermetic case. When a shape of a corner part of an end case is made more similar to a spherical shape in order to enhance the pressure resistance of the hermetic case, the end case is made larger in the axial direction, thereby upsizing the hermetic rotary compressor. In particular, in the case of a vertically-installed structure, when the hermetic case becomes larger in the axial direction, the quantity of oil to be sealed in the hermetic case is increased, thereby making the hermetic rotary compressor heavier. An increase in the oil quantity is not desirable from the viewpoint of running costs and natural resources saving.

Citation List

Additional Patent Literature: JP 3958443 B

Summary of Invention

Technical Problem

Embodiments described herein aim to provide a hermetic rotary compressor capable of improving the pressure resistance of the hermetic case and restraining upsizing of the hermetic case, and refrigeration cycle device provided with the hermetic rotary compressor.

Solution to Problem

According to one embodiment, a hermetic rotary compressor is provided with the features according to claim 1.
A refrigeration cycle device of an embodiment is provided with the aforementioned hermetic rotary compressor and a refrigeration cycle circuit. In the refrigeration cycle circuit, a heat radiator, expanding device, and heat absorber are connected to each other in sequence, and a working fluid circulates through the circuit. The hermetic rotary compressor is connected to the refrigeration cycle circuit between the heat radiator and heat absorber.
Brief Description of Drawings

FIG. 1 is a cross-sectional view showing an example of a hermetic rotary compressor of a first embodiment.
FIG. 2 is a cross-sectional view showing an example of a hermetic rotary compressor of a second embodiment.

Mode for Carrying Out the Invention Hereinafter, a hermetic rotary compressor of each of embodiments will be described with reference to FIG. 1 and FIG. 2. FIG. 1 is a cross-sectional view showing an example of a hermetic rotary compressor K of a first embodiment. Further, FIG. 1 also shows the configuration of a refrigeration cycle device provided with the hermetic rotary compressor K at the same time. In the following descriptions, the hermetic rotary compressor K will be simply referred to as a compressor K.
As shown in FIG. 1, the refrigeration cycle device includes, as major elements, a compressor K, heat radiator 2, expanding device 3, and heat absorber 4. The heat radiator 2, expanding device 3, and heat absorber 4 are connected to each other in sequence through refrigerant pipes P. The compressor K is connected between the heat radiator 2 and heat absorber 4. An accumulator 5 is annexed to the compressor K. The major elements of the refrigeration cycle device constitute a refrigeration cycle circuit T through which the working fluid circulates.
The compressor K is provided with a hermetic case 10, electric motor section 11, and compression element 12 constituted of a plurality of compression mechanism sections, and rotating shaft 13. The electric motor section 11 is an example of a driving element. The electric motor section 11 and compression element 12 are accommodated in the hermetic case 10 and are coupled to each other through the rotating shaft 13.
In the example shown in FIG. 1, the compressor K is configured as a vertical rotary compressor. It should be noted that the compressor K is not limited to the vertical type, and may also be a horizontal rotary compressor. In the description of FIG. 1, a direction from the electric motor section 11 toward the compression element 12 along the rotating shaft 13 is called a "downward direction" or a "lower part" and, a direction opposite thereto is called an "upward direction" or an "upper part". Further, a length in the axial direction of the rotating shaft 13 is simply referred to as a "height".
Inside the hermetic case 10, lubricating oil is retained in an oil basin section Z located at a lowermost end, and the remaining space is filled with refrigerant gas serving as the working fluid. The compressor K of the first embodiment uses a carbon dioxide (CO₂) refrigerant as the working fluid. The carbon dioxide refrigerant has working pressure higher than the HFC-based refrigerant. Accordingly, high pressure resistance is required of the hermetic case 10 of the compressor K.
The hermetic case 10 is constituted of a main case 10a, lower end case 10c, and upper end case 10b. The main case 10a is formed into a cylindrical shape both ends of which are opened. The lower end case 10c is formed into a dish-like shape having an outer diameter smaller than an inner diameter of the main case 10a, and is fitted into a lower end of the main case 10a. The lower end case 10c is an example of an end case.
The upper end case 10b has a shape roughly identical to the lower end case 10c, and is fitted into an upper end of the main case 10a. The lower end case 10c and upper end case 10b are coupled to the main case by welding or the like. It should be noted that the main case 10a and upper end case 10b may be formed integral with each other to thereby form a closed-end cylindrical configuration. The upper end case 10b is another example of an end case.
In the hermetic rotary compressor K, a carbon dioxide refrigerant having high working pressure is used, and hence the main case 10a, upper end case 10b, and lower end case 10c constituting the hermetic case 10 each have a heavy wall thickness. A wall thickness of a hermetic case using an HFC-based refrigerant is, for example, 3 to 4 mm. A wall thickness of the hermetic case 10 according to the first embodiment is, for example, 7 to 8 mm.
In the compressor K, each of the end cases of the hermetic case 10 is not formed into a flat-plate shape, and is formed into a dish-like shape, and hence the pressure resistance thereof can be enhanced. The end cases are fitted into the main case 10a, and hence the end cases can be made compact in size. An outer diameter of the end case is smaller than an outer diameter of the main case 10a by twice the wall thickness.
A suction refrigerant pipe Pa and lead-out refrigerant pipe Pb are attached to the hermetic case 10. The suction refrigerant pipe Pa penetrates the main case 10a to thereby make the inside and outside of the hermetic case 10 communicate with each other. The lead-out refrigerant pipe Pb penetrates the upper end case 10b to thereby make the inside and outside of the hermetic case 10 communicate with each other. The suction refrigerant pipe Pa is connected to the heat absorber 4 through the accumulator 5. The lead-out refrigerant pipe Pb is connected to the heat radiator 2.
The electric motor section 11 is provided with a stator 15 and rotor 16. The rotor 16 is fixed to the rotating shaft 13. The stator 15 is fixed to an inner circumferential surface of the hermetic case 10. An inner circumferential surface of the stator 15 is opposed to an outer circumferential surface of the rotor 16 with a slight gap held between them.
The compression element 12 is positioned beneath the electric motor section 11 serving as a driving element. The compression element 12 is provided with, for example, a first compression mechanism section 18A, second compression mechanism section 18B, intermediate partition plate 20, main bearing 23, sub-bearing 24, and valve covers 27 and 28. The first and second compression mechanism sections 18A and 18B are provided with first and second cylinders 21 and 22, respectively.
The compression element 12 is an example of a plurality of compression mechanism sections. It should be noted that the number of compression mechanism sections is not limited to two cylinders. The compression element 12 may be of a multi-cylinder type including third and fourth compression mechanism sections in addition to the first and second compression mechanism sections 18A and 18B.
The main bearing 23 is fixed to the inner circumferential surface of the hermetic case 10 by, for example, welding. The valve cover 27, main bearing 23, first cylinder 21, intermediate partition plate 20, second cylinder 22, sub-bearing 24, and valve cover 28 are laid one on top of another in sequence from the electric motor section 11 side, and are fixed to each other by, for example, jointly fastening.
The main bearing 23 and sub-bearing 24 rotatably support the rotating shaft 13. The valve covers 27 and 28 cover the main bearing 23 and sub-bearing 24, respectively. An undersurface of the sub-bearing 24 is an example of an end section of the compression element 12.
In the first cylinder 21, a circular first cylinder chamber Sa interposed between the main bearing 23 and intermediate partition plate 20 is formed. In the second cylinder 22, a circular second cylinder chamber Sb interposed between the intermediate partition plate 20 and sub-bearing 24 is formed. Each of the first and second cylinder chambers Sa and Sb is formed into a shape having an identical diameter and height.
The rotating shaft 13 includes first and second eccentric sections a and b protruding in directions perpendicular to the axial direction. The first and second eccentric sections a and b are arranged in such a manner as to be shifted from each other by, for example, 180° with respect to the center of the rotating shaft 13. Cylindrical rollers 25 and 26 are respectively fitted on the first and second eccentric sections a and b.
The first eccentric section a and roller 25 are arranged in the first cylinder chamber Sa. The second eccentric section b and roller 26 are arranged in the second cylinder chamber Sb. When the rotating shaft 13 rotates, the roller 25 rolls in a state where the roller 25 is in contact with the first cylinder chamber Sa, and roller 26 rolls in a state where the roller 26 is in contact with the second cylinder chamber Sb.
In the first cylinder 21, a blade storing groove extending in a radial direction of the first cylinder chamber Sa is formed. In the second cylinder 22, a blade storing groove extending in a radial direction of the second cylinder chamber Sb is formed. In the blade storing grooves of the first and second cylinders 21 and 22, blades 30 and 32 are respectively stored in a protrudable/retractable manner.
A tip end of the blade 30 is in slidable contact with an outer circumferential surface of the roller 25 to thereby separate the first cylinder chamber Sa into two parts. Likewise, a tip end of the blade 32 is in slidable contact with an outer circumferential surface of the roller 26 to thereby separate the second cylinder chamber Sb into two parts.
In the blade storing groove of the first cylinder 21, a horizontal hole configured to arrange therein a coil spring 31 is formed. A base end of the blade 30 is pressed against the roller 25 by the coil spring 31. The coil spring 31 is an example of an elastically energizing member.
On the other hand, in the blade storing groove of the second cylinder 22, no horizontal hole for arranging therein a coil spring 31 is formed. The blade storing groove of the second cylinder 22 communicates with the inside of the hermetic case 10. A base end of the blade 32 is pressed against the roller 26 by the pressure of the working fluid filling the hermetic case 10.
The blade 30 of the first compression mechanism section 18A is provided with the elastically energizing member, and hence is pressed against the roller 25 at all times without being subject to the pressure inside the hermetic case 10. On the other hand, the blade 32 of the second compression mechanism section 18B is not pressed against the roller 26 immediately after starting of the electric motor section 11 when the pressure inside the hermetic case 10 is low. When the pressure inside the hermetic case 10 is raised by the first compression mechanism section 18A, the blade 32 enters a state where the blade 32 is pressed against the roller 26.
The second cylinder 22 has no need of space for arrangement of the elastically energizing member, and hence can be configured more compact in size than the first cylinder 21. In the second cylinder 22, a horizontal hole for arrangement of the elastically energizing member is not formed, and hence, although the second cylinder 22 is smaller than the first cylinder 21 in diameter, sufficient pressure resistance can be secured.
In the first cylinder 21, a suction hole is formed. In the suction hole, the aforementioned suction refrigerant pipe Pa is inserted. The suction hole and inside of the second cylinder chamber Sb communicate with each other by a branch suction path. The suction hole and branch suction path will be described later with reference to FIG. 2.
The working fluid to be supplied from the refrigeration cycle circuit T through the suction refrigerant pipe Pa is guided from the suction hole to the first cylinder chamber Sa, and is then guided from the branch suction path to the second cylinder chamber Sb. The working fluid is compressed by the first and second cylinder chambers Sa and Sb concomitantly with the rotation of the rotating shaft 13.
The working fluid compressed by the first cylinder chamber Sa is discharged into the inside of valve cover 27 through a discharge valve mechanism provided to the main bearing 23, and is then supplied to the inside of the hermetic case 10 from a discharge hole formed in the valve cover 27.
The working fluid compressed by the second cylinder chamber Sb is discharged into the inside of the valve cover 28 through a discharge valve mechanism provided to the sub-bearing 24. The inside of the valve cover 28 communicates with the inside of the valve cover 27 by a discharge gas guide passage penetrating the main bearing 23, first cylinder 21, intermediate partition plate 20, second cylinder 22, and sub-bearing 24. The working fluid discharged into the inside of the valve cover 28 is supplied to the inside of the hermetic case 10 through the inside of the valve cover 27.
As shown in FIG. 1, in the axial direction of the rotating shaft 13, the whole of the first cylinder 21 is positioned inside the main case 10a. At least part of the second cylinder 22 is positioned inside the lower end case 10c.
The compressor K of the first embodiment is characterized in that the maximum distance L from the center of the rotating shaft 13 to the outer circumference of the first cylinder 21 is greater than the maximum distance M from the center of the rotating shaft 13 to the inner circumference of the lower end case 10c. Accordingly, the maximum distance L from the center of the rotating shaft 13 to the outer circumference of the first cylinder 21 is greater than the maximum distance from the center of the rotating shaft 13 to the outer circumference of the second cylinder 22. The second cylinder 22 is formed more compact than the first cylinder 21 in size.
The compressor K of the first embodiment configured as described above is provided with the compression element 12 constituted of a plurality of compression mechanism sections. Of the plurality of compression mechanism sections, the second compression mechanism section 18B is configured in such a manner that at least part of the second cylinder 22 thereof is positioned inside the lower end case 10c in the axial direction of the rotating shaft 13.
When the shape of the lower end case 10c is made more similar to a spherical shape in order to enhance the pressure resistance, the dimension of the lower end case 10c becomes larger in the axial direction of the rotating shaft 13. However, in the first embodiment, at least part of the second cylinder 22 is positioned inside the lower end case 10c in the axial direction of the rotating shaft 13.
According to the first embodiment, it is possible to allow at least part of the second cylinder 22 to be positioned inside the lower end case 10c, and thereby form the main case 10a short, and hence it is possible to prevent the hermetic case 10 from becoming larger in size while enhancing the pressure resistance.
The lower end case 10c according to the first embodiment is fitted into the main case 10a, and the lower end case 10c can be formed smaller in diameter than the main case 10a in the radial direction. In the first embodiment, even when the lower end case 10c is made larger in the axial direction, the oil basin section Z formed by the lower end case 10c does not become excessively large in the radial direction.
As a result, it is possible to prevent an excessive amount of lubricating oil from being retained in the oil basin section Z, and prevent the weight of the compressor K from increasing. It is possible to prevent the environmental load and running costs resulting from use of an excessive amount of lubricating oil from increasing. It is possible to contribute to downsizing and weight reduction of the compressor K.
The second compression mechanism section 18B according to the first embodiment utilizes the pressure inside the hermetic case 10 as means for pressing the blade 32. It is not necessary to form a horizontal hole configured to provide therein a coil spring 31 in the second cylinder 22 according to the first embodiment.
In the first embodiment, the horizontal hole making the rigidity the lowest in the cylinder is made unnecessary, and hence, even when the maximum distance from the center of the rotating shaft 13 to the outer circumference of the second cylinder 22 is made small, the rigidity of the second cylinder 22 can be secured. The second cylinder 22 can be formed small, and hence as described previously it is possible to configure a compressor K in which at least part of the second cylinder 22 is made inside the lower end case 10c.
In the first embodiment, of the plurality of compression mechanism sections, the first compression mechanism section 18A is configured in such a manner that the whole of the first cylinder 21 is positioned inside the main case 10a in the axial direction of the rotating shaft 13, and thus the outer diameter of the first cylinder 21 can be made larger than the inner circumference of the lower end case 10c.
When the pressure inside the hermetic case 10 is utilized as means for pressing the blade 32, of the plurality of compression mechanism sections, at least one cylinder should be provided with a blade 30 pressed by an elastically energizing member. The horizontal hole storing therein the elastically energizing member is the part at which the rigidity is the lowest in the cylinder.
Further, of the plurality of compression mechanism sections, at least one cylinder is connected to the suction refrigerant pipe Pa penetrating the cylinder. The suction hole (d) in which the suction refrigerant pipe Pa is to be inserted is the part at which the rigidity is the lowest in the cylinder as in the case of the horizontal hole configured to store therein the elastically energizing member.
In the first embodiment, the horizontal hole and suction hole (d) are formed in only the first cylinder 21 having a sufficient wall thickness, and these holes are not formed in another cylinder. According to the first embodiment, it is possible to form the first cylinder 21 larger in the radial direction, and secure a sufficient wall thickness. Accordingly, even when the horizontal hole and suction hole (d) are formed in the first cylinder 21, rigidity can be secured to the first cylinder 21.
Next, a compressor Ka of a second embodiment will be described below with reference to FIG. 2. FIG. 2 is a cross-sectional view showing an example of a hermetic rotary compressor Ka of a second embodiment. In the second embodiment, the configuration of a main bearing 23 differs from the main bearing 23 of the first embodiment. Other configurations are identical to the first embodiment. Configurations having functions identical to or similar to the configurations described in the first embodiment are denoted by reference symbols identical to the first embodiment to thereby enable reference to corresponding descriptions of the first embodiment, and duplicated descriptions are omitted.
In the hermetic rotary compressor Ka of the second embodiment, a main bearing 23 is divided into frames 230a and 230b. The frame 230a is fixed to an inner circumferential surface of the main case 10a of a hermetic case 10 by, for example, welding. The frame 230a is stacked on the outer circumferential portion of the first cylinder 21 and fixed to the first cylinder 21 via a fixing bolt 35a.
The frame 230b is surrounded by the frame 230a and is located on the first cylinder 21. Further, the frame 230b is fixed to the first cylinder 21 via a fixing bolt 35b, and rotatably supports a rotating shaft 13.
When the compressor Ka is to be assembled, first the frame 230a is fixed to the inner circumferential surface of the main case 10a as a single item. Subsequently, the frame 230b in a state where first and second cylinders 21 and 22 are attached thereto is fixed to the frame 230a. The main bearing 23 is divided into the frames 230a and 230b, whereby it is possible to further enhance the assembly accuracy of the frame 230a with respect to the main case 10a.
As described previously with reference to FIG. 1, the first cylinder 21 is formed in such a manner that the maximum distance L from the center of the rotation shaft 13 to the outer circumference of the first cylinder 21 is made larger than the maximum distance M from the center of the rotating shaft 13 to the inner circumference of the lower end case 10c. The first cylinder 21 is sufficiently large in size, and hence even when a screw hole for fastening by the fixing bolts 35a and 35b is formed in the first cylinder 21, the rigidity of the first cylinder 21 can be secured.
As described previously, the second cylinder 22 is formed smaller than the first cylinder 21. The outer circumference of the second cylinder 22 is located at a more inward position than the screw hole of the fixing bolt 35a, and hence the second cylinder 22 can easily be attached to the first cylinder 21.
Subsequently, a configuration common to the first and second embodiments will be described below in more detail. Each of the compressors K and Ka includes a suction hole (d) and a branch suction path (d1, e, f) shown in FIG. 2. The suction hole (d) is formed in the first cylinder 21, and extends in the radial direction of the first cylinder chamber Sa.
The branch suction path (d1, e, f) includes a branch hole (d1), suction guide hole (e), and guide groove (f). The suction guide hole (e) is formed in the intermediate partition plate 20, and penetrates the intermediate partition plate 20 in the vertical direction. The branch hole (d1) is formed in the first cylinder 21, and communicates with the suction hole (d) and suction guide hole (e). The guide groove (f) is formed in the second cylinder 22, and communicates with the second cylinder chamber Sb and suction guide hole (e) .
As shown in FIG. 2, it is assumed that a distance from an upper end face of the second cylinder 22 to an end section of the compression element 12 is H1, distance from a lower end face of the second cylinder 22 to the end section of the compression element 12 is H2, and radius of curvature of the corner part of the lower end case 10c is R. In the example shown in FIG. 2, the end section of the compression element 12 is an undersurface of the valve cover 28. The compressors K and Ka of the first and second embodiments are configured to satisfy the condition H1>R>H2.
Assuming that the compressors K and Ka are configured to satisfy the condition H1<R, the amount of lubricating oil retainable in the lower end case 10c decreases to an extreme, and there is a fear that a shortage of lubricating oil will be caused to the compression element 12. Assuming that the compressors K and Ka are configured to satisfy the condition H2>R, the pressure resistance of the lower end case 10c is lowered.
Conversely, in the first and second embodiments, the condition H1>R is satisfied, and hence an appropriate amount of lubricating oil can be retained in the lower end case 10c. Lubricating oil is supplied to slide components constituting the compression element 12, whereby the reliability of the compression element 12 can be secured.
Moreover, in the first and second embodiments, the condition R>H2 is satisfied, and hence it is possible to make the shape of the lower end case 10c more similar to a spherical shape, and enhance the pressure resistance. Accordingly, the rigidity of the hermetic case 10 can be secured without excessively increasing the wall thickness of the hermetic case 10. According to the compressors K and Ka of the first and second embodiments, it is possible to enhance the pressure resistance of the hermetic case 10 and prevent the hermetic case 10 from becoming larger in size.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions.

Reference Signs List

2 ··· heat radiator, 3 ··· expanding device, 4 ··· heat absorber, 5 ··· accumulator, 10 ··· hermetic case, 10a ··· main case, 10b ··· upper end case, 10c ··· lower end case, 11 ··· electric motor section, 12 ··· compression element, 13 ··· rotating shaft, 15 ··· stator, ···16 ··· rotor, 18A ··· first compression mechanism section, 18B ··· second compression mechanism section, 10a ··· main case, 10c ··· end case (lower end case), 21 ··· first cylinder, 22 ··· second cylinder, 25, 26 ··· roller, 20 ··· intermediate partition plate, 23 ··· main bearing, 230a, 230b ··· frame, 24 ··· sub-bearing, 27, 28 ··· valve cover (example of an end section of a plurality of compression mechanism sections), 30, 32 ··· blade, 31 ··· elastically energizing member (coil spring), 35a, 35b ··· fixing bolts, a ··· first eccentric section, b ··· second eccentric section, d ··· suction hole, d1, e, f ··· branch suction path, H1 ··· distance from an upper end face of the second cylinder to an end section of a plurality of compression mechanism sections, H2 ··· distance from a lower end face of the second cylinder to the end section of the plurality of compression mechanism sections, K ··· hermetic rotary compressor, L ··· maximum distance from the center of the rotating shaft to the outer circumference of the first cylinder, M ··· maximum distance from the center of the rotating shaft to the inner circumference of the end case, Pa ··· suction refrigerant pipe, R ··· radius of curvature of the corner part of the end case, Sa ··· first cylinder chamber, Sb ··· second cylinder chamber and T ··· refrigeration cycle circuit.

Claims

A hermetic rotary compressor comprising:
a hermetic case (10) which comprises a main case (10a) including an opening and having a cylinder shape, and an end case (10c) fitted into inside of the opening of the main case (10a) and protruding to outside the main case (10a) from the opening, and in which a lubricant oil is stored;

a rotating shaft (13) accommodated in the hermetic case (10);

an electric motor section (11) accommodated in the hermetic case (10) and configured to rotate the rotating shaft (13);

a suction refrigerant pipe (Pa) which penetrates the main case (10a), and makes inside and outside of the hermetic case (10) communicate with each other, and to which a refrigerant is supplied; and

a compression element (12)accommodated in the hermetic case (10), coupled to the rotating shaft (13), and configured to compress the refrigerant supplied from the suction refrigerant pipe (Pa), wherein the compression element includes:
a first compression mechanism section (18A) comprising a first cylinder (21) comprising a first cylinder chamber (Sa), a suction hole (d) which is formed in the first cylinder (21) and is connected to the first cylinder chamber (Sa) and into which the suction refrigerant pipe (Pa) is inserted, a roller (25) fitted on the rotating shaft (13) and configured to compress the refrigerant in the first cylinder chamber, and a blade (30) in contact with the roller and dividing the refrigerant into two parts in the first cylinder chamber and

a second compression mechanism section (18B) comprising a second cylinder (22) comprising a second cylinder chamber (Sb), a roller (26) fitted on the rotating shaft (13) and configured to compress the refrigerant in the second cylinder chamber, and a blade (32) in contact with the roller (26) and dividing the refrigerant into two parts in the second cylinder chamber, the second compression mechanism section (18B) provided adjacent to the first compression mechanism section (18A) in an axial direction of the rotating shaft (13); and

the whole of the first cylinder (21) is positioned inside the main case (10a) in the axial direction of the rotating shaft (13), and at least part of the second cylinder (22) is positioned inside the end case, and

a maximum distance (L) from a center of the rotating shaft (13) to an outer circumference of the first cylinder is greater than a maximum distance (M) from the center of the rotating shaft to an inner circumference of the end case, and

characterized in that

the blade (30) of the first cylinder (21) is pressed against the roller (25) by an elastically energizing member (31) provided in the first cylinder (21), and the blade (32) of the second cylinder (22) is pressed against the roller (26) by the pressure of the refrigerant inside the hermetic case (10) and

a branch suction path (d) is formed between the first compression mechanism section (18A) and the second compression mechanism section (18B), making the suction hole (d) of the first cylinder (21) and the second cylinder chamber (Sb) of the second cylinder (22) communicate with each other.
The hermetic rotary compressor of Claim 1, characterized in that it is suitable to be used with carbon dioxide as refrigerant.
The hermetic rotary compressor of Claim 1 or 2, characterized in that
a radius of curvature (R) of a corner part of the end case is less than a distance (H1) from one end face of the second cylinder on the first cylinder side to an end section of the compression element, and is greater than a distance (H2) from the other end face of the second cylinder to the end section of the compression element.
A refrigeration cycle device comprising:
a refrigeration cycle circuit (T) in which a heat radiator (2), an expanding device (3), and a heat absorber (4) are connected to each other in sequence and through which a carbon dioxide refrigerant circulates; and characterized in that

the hermetic rotary compressor of any one of Claims 2 and 3 is connected to the refrigeration cycle circuit (T) between the heat radiator (2) and the heat absorber (4).