JP6584631B2 - Rotary compressor - Google Patents

Description

  The present invention relates to a rotary compressor, and more particularly to the structure of a hermetic container of a hermetic rotary compressor.

  In a hermetic rotary compressor that is an example of a rotary compressor, internal parts such as an electric motor and a compressor are hermetically sealed in a welded integral container, and a discharge pipe that discharges refrigerant to the upper part of the hermetic container; Airtight terminals connected to internal components are provided. If the inside of the sealed container becomes high pressure during the operation of the hermetic rotary compressor, the sealed container may be deformed due to stress concentration between the discharge pipe and the airtight terminal, which may cause leakage of the refrigerant.

  In Patent Document 1, it has been proposed to improve the pressure-resistant strength of the upper closed container by forming the upper part of the closed container, which has been flat in the past, in a hemispherical shape, and disposing a discharge pipe through which the refrigerant flows in the center.

  In Patent Document 2, the upper sealed container is formed into a circular lid shape as a whole by a plurality of spherical surfaces, and the pressure-tight strength of the upper sealed container is arranged by arranging airtight terminals, accessories, etc. along the spherical surface. It has been proposed to facilitate the installation of discharge pipes and airtight terminals while improving the efficiency.

JP-A-11-159456 JP2015-124700A

  To reduce the size and increase the capacity of the rotary compressor, it is conceivable to increase the amount of refrigerant circulation. In this case, the discharge pipe diameter is increased to an appropriate size while maintaining the outer diameter of the sealed container. Therefore, it is necessary to suppress the loss in the discharge pipe. However, when the discharge pipe diameter is enlarged, the airtight terminal and the discharge pipe provided on the upper part of the sealed container are close to each other, and stress is concentrated in the region between the airtight terminal and the discharge pipe when the closed container is at high pressure. Is likely to occur. The deformation that occurs in this region is difficult to prevent even if the configurations of Patent Documents 1 and 2 are adopted, and leakage of refrigerant gas, breakage of the airtight terminal, and the like occur.

  The present invention has been made in order to solve the above-described problems. Even if the discharge pipe diameter is enlarged while maintaining the outer diameter of the sealed container, the strength of the upper sealed container can be secured, and the airtight terminal is provided. An object of the present invention is to provide a rotary compressor capable of easily arranging the above.

A rotary compressor according to the present invention includes a compression mechanism section and a sealed container that houses an electric motor section. The sealed container closes a cylindrical body and an opening at one end of the body, and discharges a refrigerant. A first sealed container having a discharge pipe connected to a central part thereof, and a second sealed container for closing an opening at the other end of the body part, wherein the first sealed container is connected to the electric motor part. A flat portion on which an airtight terminal is disposed, and at least one curved surface portion other than the flat portion, and the flat portion has a first end and a second end in a major axis direction. An axis that has an elliptical shape, is formed by an opening at the one end, is located on a virtual vertical plane that is orthogonal to the axial direction of the body portion, and is an axis obtained by projecting the major axis of the elliptical shape on the virtual vertical plane on the virtual vertical plane to the first axis perpendicular to, apart from the virtual vertical plane closer to the discharge pipe Inclined at a first inclination angle in the direction, a second axis perpendicular to the first axis in the virtual vertical plane, from said virtual vertical plane than the first end and the second end It inclines at a 2nd inclination angle in the away direction.

  According to the rotary compressor according to the present invention, the flat surface portion on which the airtight terminal is disposed is inclined at the first inclination angle and the second inclination angle with respect to the virtual vertical plane orthogonal to the axial direction of the trunk portion. As a result, the distance between the discharge pipe and the airtight terminal and the distance between the airtight terminal and the sealed container are extended, and even if the discharge pipe diameter is increased while the outer diameter of the sealed container is maintained, the stress between the discharge pipe and the airtight terminal is increased. Is prevented from being concentrated, and the sealed container is less likely to be deformed. In addition, the strength of the sealed container can be sufficiently secured, and the arrangement of the airtight terminals is facilitated.

It is an internal block diagram which shows the inside of the rotary compressor which concerns on embodiment. It is a top view of an upper airtight container. It is a figure when the cross section along the X-axis of FIG. 2 is seen in the Y direction. It is a figure when the cross section along the Y-axis of FIG. 2 is seen in a X direction. It is a graph which shows the comparison result of the deformation | transformation amount with respect to the internal pressure of the upper airtight container of this Embodiment, and the upper airtight container of a prior art example.

Embodiment.
FIG. 1 is an internal configuration diagram showing the inside of a rotary compressor 100 according to the present embodiment. In the following description, as the rotary compressor 100, a twin rotary type rotary compressor 100 having two cylindrical cylinders 25 in the compression mechanism unit 2 will be described as an example. As shown in FIG. 1, the rotary compressor 100 is a hermetic electric compressor in which a compression mechanism unit 2 and an electric motor unit 3 are accommodated in a hermetic container 1. A suction muffler 14 is connected to the sealed container 1, and refrigerant is sucked from the suction muffler 14, compressed to a high pressure, and discharged.

  The sealed container 1 includes a cylindrical body 11, an upper sealed container 12 that closes an opening on the upper side of the body 11, and a lower sealed container 13 that closes an opening on the lower side of the body 11. The upper sealed container 12 is an example of a first sealed container of the present invention, and the lower sealed container 13 is an example of a second sealed container of the present invention. The parts to which they are connected are fixed by welding and kept sealed. The body 11 is provided with a suction pipe 15 connected to the suction muffler 14, and the upper sealed container 12 is provided with a discharge pipe 4. The discharge pipe 4 is on the extension line of the rotating shaft 21 and is installed at the center of the upper sealed container 12. The upper sealed container 12 is provided with an airtight terminal 16 and a rod 7 which are electrically connected to the electric motor unit 3 in the sealed container 1. A cover for protecting the airtight terminal 16 is attached to the rod 7. The lower sealed container 13 has a shape approximated to a hemispherical shape. The lower sealed container 13 may be provided with an oil supply mechanism that stores lubricating oil supplied to the compression mechanism unit 2.

  The electric motor unit 3 includes a rotor 31 and a stator 32. The stator 32 is shrink-fitted to the body 11 of the sealed container 1 and fixed by various fixing methods such as welding, and is electrically connected to the airtight terminal 16 provided on the upper sealed container 12 by lead wires.

  The compression mechanism unit 2 includes a rotary shaft 21, a main bearing 22, a sub bearing 23, a rolling piston 24, a cylindrical cylinder 25, and a vane 26. The rotating shaft 21 is fixed to the rotor 31 of the electric motor unit 3 and is held by the main bearing 22 and the sub bearing 23. The rolling piston 24 is fixed to the rotary shaft 21 and accommodated in the cylindrical cylinder 25 so as to be eccentrically rotatable. The cylindrical cylinder 25 is divided for each compression chamber by a vane 26, moves through the compression chamber, and the high-pressure refrigerant is discharged into the space inside the sealed container 1.

  FIG. 2 is a top view of the upper sealed container 12. As shown in FIG. 2, the upper closed container 12 connected to the body 11 on the XY plane formed by the upper end of the cylindrical body 11 has a circular shape when viewed from above, and a discharge pipe is formed at the center of the container. 4 is provided. The surface of the upper sealed container 12 is composed of a flat surface portion 17 and a curved surface portion 18. The flat surface portion 17 has an elliptical shape having end portions 17 a and 17 b, and an edge portion is connected to the curved surface portion 18.

  The flat surface portion 17 is formed in an elliptical shape, and one end portion 17 a is provided with a plurality of airtight terminals 16 to which the electric motor portion 3 inside the sealed container 1 is connected and the outermost shell 16 a is continuous with the flat surface portion 17. ing. In addition, a rod 7 perpendicular to the planar portion 17 is provided at the other end 17 b of the planar portion 17. The discharge pipe 4 provided at the center of the upper sealed container 12 has an outer diameter of 0.1 to 0.2 times the outer diameter of the upper sealed container 12. On the other hand, of the surface of the upper closed container 12, the curved surface portion 18 is formed in a shape approximated to a hemispherical shape by a plurality of curved surfaces, for example.

  FIG. 3 is a view when a cross section along the X axis in FIG. 2 is viewed in the Y direction. As shown in FIG. 3, when the plane portion 17 is viewed in the Y direction, the plane portion 17 is inclined at an angle of θ1 with respect to the XY plane formed at the upper end of the body portion 11, and the edge of the plane portion 17 is The curved portion 18 is connected to the curved portion 18a by a smooth curve. Specifically, it is formed at the upper end of the body portion 11 and is inclined at an inclination angle θ1 in a direction away from the XY plane with respect to the X axis located on the XY plane orthogonal to the axial direction of the body portion 11. . The inclination angle θ1 is, for example, θ1 = 5 °, and one end 17a of the flat surface portion 17 protrudes outward from the hemispherical surface formed by the curved surface portion 18. The distance from one end 17a of the plane portion 17 to the XY plane formed by the upper end of the body 11 is farther than the distance from the other end 17b to the XY plane formed by the upper end of the body 11. positioned. The flat surface portion 17 inclined at the inclination angle θ1 is connected to the curved surface portion 18 by the concave portion 18a, so that the distance along the surface between the outermost shell 16a of the airtight terminal 16 and the side surface of the discharge pipe 4, and the airtightness The distance along the surface between the outermost shell 16a of the terminal 16 and the inner surface of the upper sealed container 12 is increased. The concave portion 18a is formed thick and has a function as a rib for improving strength.

  FIG. 4 is a view when a cross section along the Y-axis in FIG. 2 is viewed in the X direction. As shown in FIG. 4, when the plane portion 17 is viewed in the X direction, the plane portion 17 is inclined at an angle of θ2 = 10 °, for example, with respect to the XY plane formed at the upper end of the body portion 11. Specifically, it is inclined with respect to the Y axis orthogonal to the X axis at an inclination angle θ2 in a direction away from the XY plane. Also in this case, the flat surface portion 17 is inclined at the inclination angle θ2, so that the distance along the surface between the outermost shell 16a of the hermetic terminal 16 and the side surface of the discharge pipe 4 and the outermost of the hermetic terminal 16 are increased. The distance along the surface between the shell 16a and the inner surface of the upper closed vessel 12 is increased. Also when viewed in the Y direction, one end 17a of the flat surface portion 17 protrudes from the curved surface portion 18, and the edge portion of the flat surface portion 17 is connected to the curved surface portion 18 by a smooth curve of the concave portion 18a. Yes. Note that the XY plane is an example of a virtual vertical plane of the present invention, the X axis and the Y axis are examples of a first axis and a second axis, and the tilt angle θ1 and the tilt angle θ2 are the first tilt angle and It is an example of the 2nd inclination angle.

  As described above, the plane portion 17 has an inclination with respect to the upper end surface of the body portion 11 in two cross sections in the X direction and the Y direction orthogonal to each other when the upper sealed container 12 is viewed from above, and is formed by the recess 18a. The curved surface portion 18 is smoothly connected. Therefore, even when the distance between the airtight terminal 16 and the discharge pipe 4 is maintained when viewed from above, the distance along the surface between the outermost shell 16 a of the airtight terminal 16 and the side surface of the discharge pipe 4. And the distance along the surface between the outermost shell 16a of the airtight terminal 16 and the inner surface of the upper sealed container 12 is extended. By increasing the inclination angles θ <b> 1 and θ <b> 2 of the flat surface portion 17, one end portion 17 a of the flat surface portion 17 is further away from the curved surface portion 18, and one end portion 17 a of the flat surface portion 17 protrudes from the curved surface portion 18. The distance to the XY plane is large. Therefore, the distance along the surface from the airtight terminal 16 to the discharge pipe 4 is further extended.

  If the diameter of the sealed container is 100 mm and the flat surface portion 17 is not inclined, the distance between the side surface of the discharge pipe 4 and the outermost shell 16a of the hermetic terminal 16 and the outermost shell 16a of the hermetic terminal 16 will be described. And a sufficient distance from the inner surface of the upper sealed container 12 cannot be secured. On the other hand, the distance between the flat portion 17 inclined at the inclination angles θ1, θ2 and the side surface of the discharge pipe 4 and the outermost shell 16a of the hermetic terminal 16 is 5 mm, and the outermost shell 16a of the hermetic terminal 16 and the upper sealed container 12 are set. The distance between the inner surface and the inner surface is 5 mm, and the design conforming to the regulation of the insulation distance is possible. Therefore, the distance between the side surface of the discharge pipe 4 and the outermost shell 16a of the airtight terminal 16 is 5 mm or more, and the distance between the outermost shell 16a of the airtight terminal 16 and the inner surface of the upper sealed container 12 is 5 mm or more. It is desirable. In addition, the inclination angles θ1 and θ2 of the plane portion 17 are preferably 5 ° or more and 30 ° or less with respect to the XY plane. By setting the inclination angles θ1 and θ2 in this range, the distance between the side surface of the discharge pipe 4 and the outermost shell 16a of the hermetic terminal 16, the outermost shell 16a of the hermetic terminal 16, and the inner surface of the upper sealed container 12 The distance between is secured. In addition, since the flat surface portion 17 is inclined, the airtight terminal 16 is prevented from jumping out of the opening of the upper sealed container 12 in a plan view.

  Next, the operation of the rotary compressor 100 will be described. The rotary compressor 100 sucks the refrigerant from the suction muffler 14 through the suction pipe 15. The refrigerant sucked from the suction pipe 15 is introduced into the compression mechanism unit 2, is compressed in the compression mechanism unit 2, becomes a high-temperature / high-pressure gas refrigerant, and is discharged into the sealed container 1. The gas refrigerant passes through the gap between the inner surface of the sealed container 1 and the electric motor unit 3 and is discharged from the discharge pipe 4 of the upper sealed container 12. As a result, a high-temperature and high-pressure gas refrigerant is generated by the rotary compressor 100.

  When the refrigerant compressed in the compression mechanism unit 2 is discharged into the closed container 1, the sealed container 1 receives an outward force from the high-temperature and high-pressure gas refrigerant. Among the sealed containers 1, the body 11 and the lower sealed container 13 have a shape approximate to a cylindrical shape and a hemispherical shape, so that stress concentration due to an outward force is reduced.

  On the other hand, the upper airtight container 12 has a surface formed by an elliptical flat surface portion 17 and a curved surface portion 18 approximated to a hemispherical shape. The flat surface portion 17 is provided with an airtight terminal 16 and a rod 7 to which a cover for protecting the airtight terminal 16 is attached, and the curved surface portion 18 is provided with a discharge pipe 4 at a center position of the upper sealed container 12. ing. The flat surface portion 17 is inclined in two directions, and one end portion 17a of the elliptical flat surface portion 17 protrudes outward from the curved surface portion 18 of the upper closed container 12 and is higher than the center of the upper closed container 12. Has been extended. Further, the flat surface portion 17 and the curved surface portion 18 are connected by a smooth curved concave portion 18a. Therefore, the distance between the airtight terminal 16 and the discharge pipe 4 is increased as compared with the case where the upper sealed container 12 is flat or a plane along a spherical shape. The concave portion 18a has an increased thickness and functions as a rib.

  In this way, the upper closed container 12 has a surface formed by the flat surface portion 17 and the curved surface portion 18, and a smooth concave portion 18a in which the edge portion of the flat surface portion 17 where stress is particularly concentrated is formed thick. To the curved surface portion 18. A region other than the flat surface portion 17 in the upper sealed container 12 is formed by a curved surface portion 18 approximated to a hemispherical shape. Thereby, even if the pressure inside the airtight container 1 rises, stress concentration is reduced, and deformation of the upper airtight container 12 is suppressed.

  The plane portion 17 is inclined in two directions, and the distance between the airtight terminal 16 provided on the plane portion 17 and the discharge pipe 4 provided on the curved surface portion 18 is extended. Therefore, for example, even when the discharge pipe 4 having a diameter 0.1 times larger than the outer diameter of the upper sealed container 12 is used, the airtight terminal 16 and the discharge pipe 4 can be arranged sufficiently separated from each other. It becomes.

  The airtight terminal 16 requires a cover for covering the airtight terminal 16, and for this purpose, the rod 7 for attaching the cover must also be disposed. The flat surface portion 17 protrudes outward from the curved surface portion 18 of the upper sealed container 12, extends to a high position, and has a large area. Therefore, it is easy to arrange or attach the airtight terminal 16 and the rod 7 and to attach the cover to the rod 7.

Performance evaluation.
In the performance evaluation, the upper closed container 12 of the rotary compressor 100 according to the present embodiment and the conventional upper closed container were subjected to numerical analysis and the deformation amount under load was calculated and compared. In the upper sealed container 12 according to the present embodiment, the inclination of the plane portion 17 is set so as to have an inclination angle of 10 ° with respect to the X axis and 15 ° with respect to the Y axis in FIG. In the upper sealed container of the comparative example, the airtight terminal was provided with a flat surface with no inclination, and a discharge pipe was provided at the center of the upper sealed container. The outer diameter and plate thickness of the upper sealed container of the comparative example were the same as those of the upper sealed container 12. The outer diameter of the discharge pipe 4 used for the upper sealed container 12 was 1.5 times the outer diameter of the discharge pipe used for the upper sealed container of the comparative example.

  FIG. 5 is a graph showing a comparison result of the deformation amount with respect to the internal pressure of the upper sealed container 12 of the present embodiment and the upper sealed container of the conventional example. In FIG. 5, numerical analysis conditions were set for the upper closed container with a load pressure of 5 MPa, and the deformation amount under load was calculated. The black bar graph is the amount of change in the example, and the white bar graph is the amount of change in the comparative example. In the comparison, the deformation amount of the upper sealed container of the comparative example was set to 100%.

  As shown in FIG. 5, the amount of deformation between the discharge tube 4 of the upper sealed container 12 and the airtight terminal 16 is about 50 of the amount of deformation between the discharge tube of the upper sealed container of the comparative example and the airtight terminal. It has decreased to about%. Further, the deformation amount of the central portion of the hermetic terminal 16 is reduced to about 80% of the deformation amount of the central portion of the hermetic terminal of the comparative example. Thus, it is considered that the amount of deformation decreased even when the outer shape of the discharge pipe 4 increased by 1.5 times because the distance between the discharge pipe 4 and the airtight terminal 16 was sufficiently maintained. In addition, it is considered that one of the factors is that the flat portion 17 where the airtight terminal 16 is arranged and the curved surface portion 18 where the discharge pipe 4 is arranged are connected by a smooth concave portion 18a. From the above, it was found that by adopting the structure of the upper sealed container 12 of the present embodiment, the stress concentration is alleviated and the deformation of the upper sealed container 12 can be greatly reduced.

  In the above description, a twin rotary compressor having two compression chambers has been described as an example. However, the present invention is applied to a single rotary having a large refrigerant flow rate, a scroll compressor, and the like, and the discharge pipe is expanded. You can also plan.

  In the above description, the case where the compressor is applied to a vertical type compressor is described. However, in a horizontal type compressor, the vertical sealed container is press-fitted into the open part of the cylindrical sealed container. The present invention can also be applied when a discharge pipe is provided at the center.

  According to the rotary compressor 100 according to the present embodiment described above, the flat surface portion 17 on which the airtight terminal 16 is disposed is inclined at the inclination angles θ1 and θ2 from the XY plane formed by the opening of the body portion 11. Yes. Thereby, the distance along the surface between the outermost shell 16a of the hermetic terminal 16 and the side surface of the discharge pipe 4, and the surface between the outermost shell 16a of the hermetic terminal 16 and the inner surface of the upper sealed container 12. The distance along is extended. Therefore, even if the outer diameter of the discharge pipe 4 is enlarged while the outer diameter of the sealed container 1 is maintained, the strength of the sealed container 1 can be ensured. In addition, since a large area can be secured in the flat portion 17, the arrangement and connection of the airtight terminals 16 are facilitated.

  According to the rotary compressor 100 according to the present embodiment described above, the inclination angles θ1 and θ2 are formed at different angles. For this reason, the distance between the side surface of the discharge pipe 4 and the outermost shell 16a of the airtight terminal 16 and the distance between the outermost shell 16a of the airtight terminal 16 and the inner surface of the upper sealed container 12 are sufficiently secured. be able to.

  According to the rotary compressor 100 according to the present embodiment, one end portion 17a of the flat surface portion 17 is protruded from the curved surface portion 18 and the distance from the XY plane is increased. The area of the flat surface portion 17 can be sufficiently enlarged while maintaining the distance from the distance, and the distance between the airtight terminal 16 and the discharge pipe 4 can be increased.

  According to the rotary compressor 100 according to the present embodiment, the flat portion 17 and the curved surface portion 18 are connected by the concave portion 18a with a smooth curve, whereby the strength of the sealed container 1 is improved.

  According to the rotary compressor 100 according to the present embodiment, the outer diameter of the discharge pipe 4 is enlarged, and it is possible to increase the amount of refrigerant circulation while maintaining the strength of the hermetic container 1, and high-performance rotary compression. A machine 100 is obtained.

  According to the rotary compressor 100 according to the present embodiment, by setting the inclination angles θ1 and θ2 of the plane portion 17 to 5 ° or more and 30 ° or less, the distance between the airtight terminal 16 and the discharge pipe 4 is increased. And the area of the plane part 17 can be expanded sufficiently. Further, it is possible to prevent the airtight terminal 16 from protruding outward from the sealed container 1.

  According to the rotary compressor 100 according to the present embodiment, for example, even if the diameter of the sealed container is 100 mm, the distance between the side surface of the discharge pipe 4 and the hermetic terminal 16 is 5 mm or more. The distance from the side surface of the upper sealed container 12 can be 5 mm or more. Therefore, it is possible to design according to the regulation of the insulation distance.

  According to the rotary compressor 100 according to the present embodiment, since the rod 7 is provided on the flat surface portion 17, the operation of attaching the cover that covers the airtight terminal 16 becomes easy.

  According to the rotary compressor 100 according to the present embodiment, even when a refrigerant having a saturation pressure higher than that of the R22 refrigerant is compressed, safety is maintained because the strength of the sealed container 1 is sufficient.

  DESCRIPTION OF SYMBOLS 1 Airtight container, 2 Compression mechanism part, 3 Electric motor part, 4 Discharge pipe, 7 Rod, 11 Trunk part, 12 Upper airtight container, 13 Lower airtight container, 14 Inhalation muffler, 15 Inhalation pipe, 16 Airtight terminal, 16a Outermost shell , 17 plane part, 17a end part, 17b end part, 18 curved surface part, 18a recessed part, 21 rotating shaft, 22 main bearing, 23 auxiliary bearing, 24 rolling piston, 25 cylindrical cylinder, 26 vane, 31 rotor, 32 stator , 100 rotary compressor.

Claims (9)

A compression mechanism section, and a sealed container that houses the electric motor section;
The sealed container is
A cylindrical body,
A first sealed container in which an opening at one end of the body portion is closed and a discharge pipe for discharging a refrigerant is connected to a central portion;
A second sealed container that closes an opening at the other end of the body part,
The first sealed container is
A plane portion in which an airtight terminal connected to the electric motor portion is disposed;
Having at least one curved surface part other than the flat part,
The plane portion is
Having an elliptical shape having a first end and a second end in the longitudinal direction;
A first axis that is formed by the opening at the one end, is located on a virtual vertical plane that is orthogonal to the axial direction of the body portion, and that is orthogonal to the axis that projects the major axis of the elliptical shape on the virtual vertical plane on the virtual vertical plane On the other hand, as it approaches the discharge pipe, it is inclined at a first inclination angle in a direction away from the virtual vertical plane,
A second axis perpendicular to the first axis in the virtual vertical plane, said first end portion is inclined at a second inclination angle in a direction away from the imaginary vertical plane than the second end Rotary compressor. The first tilt angle and the second tilt angle are formed to be different from each other.
The rotary compressor according to claim 1. The distance between the virtual vertical plane and the position of the plane portion farthest from the virtual vertical plane is:
The rotary compressor according to claim 1 or 2, wherein the rotary compressor is larger than a distance between the virtual vertical plane and the curved surface portion. The flat surface portion and the curved surface portion are
Connected by a recess formed in the curved portion,
The rotary compressor as described in any one of Claims 1-3. The outer diameter of the discharge pipe is
It is formed to be 0.1 times or more of the outer diameter of the first sealed container,
The rotary compressor as described in any one of Claims 1-4. The first inclination angle is not less than 5 ° and not more than 30 ° with respect to the virtual vertical plane,
The second inclination angle is not less than 5 ° and not more than 30 ° with respect to the virtual vertical plane.
The rotary compressor as described in any one of Claims 1-5. The distance between the side surface of the discharge pipe and the airtight terminal is 5 mm or more,
The rotary compressor according to any one of claims 1 to 6, wherein a distance between the hermetic terminal and a side surface of the second hermetic container is 5 mm or more. The plane portion is
Provided with a rod that is provided perpendicular to the plane portion and to which a cover that covers the hermetic terminal is attached;
The rotary compressor as described in any one of Claims 1-7. The compression mechanism is
Compresses a refrigerant having a higher saturation pressure than the R22 refrigerant.
The rotary compressor as described in any one of Claims 1-8.

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