JP6262101B2 - Rotary compressor and refrigeration cycle apparatus - Google Patents

Description

  Embodiments described herein relate generally to a rotary compressor and a refrigeration cycle apparatus.

  Conventionally, there has been known a rotary compressor in which an electric motor unit and a compression mechanism unit driven by a rotating shaft connected to the electric motor unit are housed in a hermetically sealed case, and a working fluid such as a gas refrigerant is compressed by the compression mechanism unit. ing. Among such rotary compressions, a compressor having a compression mechanism having three cylinders arranged in the axial direction of the rotating shaft and at least three bearings that support the rotating shaft (described below) is known. (See Patent Documents 1 and 2).

JP2012-122400A Japanese Patent No. 4594302

  However, when three cylinders and three or more bearing parts are provided in the compression mechanism, it is not easy to align the three or more bearing parts, and it takes a lot of time to assemble the rotary compressor. . Moreover, since the length of the rotating shaft is increased by providing three cylinders, the rotating shaft is likely to be bent or deformed.

  An object of an embodiment of the present invention is to make it easy to align the bearings in a rotary compressor that supports a rotating shaft using at least three bearings, and to This is to suppress the occurrence of swinging.

  The rotary compressor according to the embodiment is a rotary compressor in which an electric motor unit and a compression mechanism unit driven by a rotary shaft connected to the electric motor unit are housed in a hermetically sealed case, and the working fluid is compressed by the compression mechanism unit. The compression mechanism section includes at least three cylinders that are arranged in the axial direction of the rotation shaft and surround the rotation shaft, a closing member that closes both ends of each cylinder to form a cylinder chamber in each cylinder, An eccentric portion provided in a portion located in each cylinder chamber, a roller that is fitted to the eccentric portion and rotates eccentrically in each cylinder chamber as the rotary shaft rotates, and a suction chamber and a compression chamber in the circumferential direction in each cylinder chamber The rotary shaft is pivotally supported by a bearing portion provided on at least three of the closing members, and a sliding portion between the inner peripheral surface of the bearing portion and the outer peripheral surface of the rotary shaft is provided. Clearance “C”, bearing When the axial length of the sliding portion between the inner peripheral surface and the outer peripheral surface of the rotating shaft is “L”, the value of “C / L” of the bearing portion located closest to the motor portion is It is smaller than the value of “C / L” of other bearing portions.

It is a block diagram of the refrigerating-cycle apparatus containing the rotary compressor shown in the cross section. It is a horizontal sectional view showing a portion of a cylinder. It is explanatory drawing about clearance "C" between the internal peripheral surface of a bearing part, and the outer peripheral surface of a rotating shaft.

  An embodiment is described based on a drawing. FIG. 1 shows the overall configuration of a refrigeration cycle apparatus 1. This refrigeration cycle apparatus 1 includes a compressor body 2 and an accumulator 3, and a rotary compressor 4 that compresses a gas refrigerant that is a working fluid. A condenser 5 connected to the compressor body 2 to condense the high-pressure and high-temperature gas refrigerant discharged from the compressor body 2 into a liquid refrigerant, and an expansion device 6 connected to the condenser 5 to decompress the liquid refrigerant. And an evaporator 7 connected between the expansion device 6 and the accumulator 3 and evaporating the expanded liquid refrigerant. The accumulator 3 and the compressor body 2 are connected by a suction flow path 8 through which a gas refrigerant flows.

  The compressor body 2 has a sealed case 9 formed in a cylindrical shape. In the sealed case 9, an electric motor unit 10 located on the upper side and a center line in the vertical direction are connected to the electric motor unit 10. The rotating shaft 11 and the compression mechanism part 12 driven by the electric motor part 10 via the rotating shaft 11 are accommodated.

  The electric motor unit 10 includes a rotor 13 to which the rotating shaft 11 is fixed, and a stator 14 that is fixed to the inner peripheral portion of the sealed case 9 and disposed at a position surrounding the rotor 13. The rotor 13 is provided with a permanent magnet (not shown), and a current-carrying coil (not shown) is wound around the stator 14. When the coil is energized, the rotor 13 and the rotating shaft 11 rotate integrally.

  The compression mechanism unit 12 is a part that compresses the gas refrigerant, and includes three cylinders 15 a, 15 b, and 15 c arranged in the axial direction of the rotary shaft 11. Both ends of each cylinder 15a, 15b, 15c along the axial direction of the rotary shaft 11 are closed by blocking members (main bearing 16, first partition plate 17, second partition plate 18, sub bearing 19), and both ends are closed. Cylinder chambers 20a, 20b, and 20c are formed in the cylinders 15a, 15b, and 15c. The rotating shaft 11 is penetrated by these closing members (the main bearing 16, the first partition plate 17, the second partition plate 18, and the auxiliary bearing 19), and the rotating shaft 11 is a bearing portion provided in the main bearing 16. 16 a, a bearing portion 18 a provided on the second partition plate 18, and a bearing portion 19 a provided on the auxiliary bearing 19. In addition, a bearing part may be provided also in the 1st partition plate 17, and what is necessary is just to provide a bearing part in at least three of the closure members.

  Eccentric portions 21a, 21b, and 21c are provided in portions of the rotary shaft 11 located in the cylinder chambers 20a, 20b, and 20c, and rollers 22a, 22b, and 22c are fitted into the eccentric portions 21a, 21b, and 21c. ing. Each roller 22a, 22b, 22c is arranged to rotate eccentrically while the outer peripheral surface is in line contact with the inner peripheral surface of each cylinder 15a, 15b, 15c via an oil film when the rotary shaft 11 rotates.

  Each cylinder chamber 20a, 20b, 20c is provided with blades 25a, 25b, 25c that bisect the inside of each cylinder chamber 20a, 20b, 20c into a suction chamber 23 and a compression chamber 24 along the circumferential direction. . The suction chamber 23 and the compression chamber 24 will be described later with reference to FIG.

  The main bearing 16 is provided with a discharge port 26 through which the gas refrigerant compressed in the cylinder chamber 20 a is discharged, and a discharge valve 27 that opens and closes the discharge port 26. Further, a main bearing side muffler 28 into which the gas refrigerant discharged from the discharge port 26 flows is attached to the main bearing 16. The gas refrigerant that has flowed into the main bearing side muffler 28 flows into the sealed case 9 from an outlet 29 formed in the main bearing side muffler 28.

  The first partition plate 17 is provided with a discharge port 30 through which the gas refrigerant compressed in the cylinder chamber 20 b is discharged, and a discharge valve 31 that opens and closes the discharge port 30. In the first partition plate 17, a partition plate inner space 32 into which the gas refrigerant discharged from the discharge port 30 flows is formed. The inside of the partition plate space 32 and the inside of the main bearing side muffler 28 are communicated with each other through the communication passage 33, and the gas refrigerant discharged from the discharge port 30 and flowing into the partition plate space 32 passes through the communication passage 33. It flows into the bearing side muffler 28.

  The auxiliary bearing 19 is provided with a discharge port 34 through which the gas refrigerant compressed in the cylinder chamber 20 c is discharged, and a discharge valve 35 that opens and closes the discharge port 34. Further, a sub bearing side muffler 36 into which the gas refrigerant discharged from the discharge port 34 flows is attached to the sub bearing 19. The sub-bearing side muffler 36 and the partition plate space 32 communicate with each other through a communication passage (not shown), and the gas refrigerant discharged from the discharge port 34 into the sub-bearing side muffler 36 passes through the partition plate space 32. Then, it flows into the main bearing side muffler 28.

  FIG. 2 is a horizontal cross-sectional view showing a portion of the cylinder 15a that is a part of the compression mechanism section 12. As shown in FIG. A blade groove 37 is formed in the cylinder 15a, and the blade 25a is accommodated in the blade groove 37 so as to be reciprocally movable. The blade 25a is urged so that the tip end abuts against the outer peripheral surface of the roller 22a. The tip of the blade 25a abuts against the outer peripheral surface of the roller 22a, so that the inside of the cylinder chamber 20a extends in the circumferential direction. It is divided into a suction chamber 38 and a compression chamber 39. The suction flow path 8 is communicated with the suction chamber 38, and the discharge port 26 is communicated with the compression chamber 39.

  The configuration of the other cylinders 15b and 15c is the same as the configuration of the cylinder 15a. Each cylinder chamber 20b and 20c is divided into a suction chamber 38 and a compression chamber 39 by each blade 25b and 25c.

  FIG. 3 is an explanatory view of the clearance “C” between the inner peripheral surface of the bearing portion 16 a and the outer peripheral surface of the rotating shaft 11. When the inner diameter dimension of the bearing portion 16a of the main bearing 16 is "D" and the outer dimension of the portion pivotally supported by the bearing portion 16a of the rotary shaft 11 is "d", the clearance "C" is "C = D- d ". Although not shown, the clearance “C” between the inner peripheral surface of the bearing portion 18 a of the second partition plate 18 and the outer peripheral surface of the rotary shaft 11, the inner peripheral surface of the bearing portion 19 a of the auxiliary bearing 19, and the rotary shaft 11. The clearance “C” between the outer peripheral surface and the outer peripheral surface is similarly expressed.

  Here, in the three bearing portions 16a, 18a, and 19a that support the rotating shaft 11, the clearance is set to “C” as described above, and the inner peripheral surfaces of these bearing portions 16a, 18a, and 19a and the rotating shaft 11 is the value of “C / L” of the bearing portion 16a located closest to the electric motor portion 10 when the length in the axial direction of the sliding portion between the outer peripheral surface 11 and the outer peripheral surface 11 is “L” (see FIG. 1). Is set smaller than the value of “C / L” of the other bearing portions 18a and 19a.

  Of the three bearing portions 16a, 18a and 19a, the “C / L” value of the bearing portions 16a and 19a located at both ends is smaller than the “C / L” value of the bearing portion 18a located therebetween. Is set.

  Returning to FIG. A ring-shaped groove 40 is formed at the end of the auxiliary bearing 19 on the side away from the motor unit 10. By forming the groove 40, the rigidity of the end portion side away from the motor unit 10 on the sliding surface with the rotating shaft 11 of the bearing unit 19 a located farthest from the motor unit 10 is It is set smaller than the rigidity of the end side near the electric motor part 10 on the sliding surface with the rotating shaft 11 of the bearing part 16a located closest.

  Next, returning to FIG. 2, the clearance “C ′” of the fitting portion between the inner peripheral surface of the roller 22a and the outer peripheral surface of the eccentric portion 21a will be described. When the inner diameter of the roller 22a is “D ′” and the outer dimension of the eccentric portion 21a is “d ′”, the clearance “C ′” is expressed as “C ′ = D′−d ′”. Although not shown, the clearance “C ′” of the fitting portion between the inner peripheral surface of the roller 22b and the outer peripheral surface of the eccentric portion 21b, and between the inner peripheral surface of the roller 22c and the outer peripheral surface of the eccentric portion 21c. The clearance “C ′” of the fitting portion is similarly expressed.

  Here, the clearance of the fitting portion between the rollers 22a, 22b, and 22c and the eccentric portions 21a, 21b, and 21c is “C ′” as described above, and the inner peripheral surface of the rollers 22a, 22b, and 22c and the eccentric portion 21a, When the length in the axial direction of the fitting portion between the outer peripheral surfaces of 21b and 21c is “L ′” (see FIG. 1), the value of “C ′ / L ′” is the value of each bearing portion 16a described above. , 18a and 19a are set to be larger than the “C / L” value.

  In such a configuration, in the rotary compressor 4, when the electric motor unit 10 is energized, the rotating shaft 11 rotates around the center line together with the rotor 13, and the compression mechanism unit 12 is driven by this rotation. The gas refrigerant is compressed in each cylinder chamber 20a, 20b, 20c.

  When the pressure of the compressed gas refrigerant reaches the set pressure, the discharge valves 27, 31, and 35 are opened, and the gas refrigerant is discharged from the discharge ports 26, 30, and 34. The gas refrigerant discharged from each of the discharge ports 26, 30, 34 flows directly into the main bearing side muffler 28, or passes through the partition plate inner space 32 and the auxiliary bearing side muffler 36, so that the main bearing side muffler 28. Flows in. The gas refrigerant that has flowed into the main bearing-side muffler 28 flows out from the outlet 29 into the sealed case 9.

  The gas refrigerant flowing into the sealed case 9 flows in the order of the condenser 5, the expansion device 6, and the evaporator 7, returns to the rotary compressor 4, and the refrigeration cycle in the refrigeration cycle apparatus 1 is executed.

  Here, in the compression mechanism part 12, the rotating shaft 11 is pivotally supported by three bearing parts 16a, 18a, 19a. In these bearing portions 16 a, 18 a, and 19 a, the value of “C / L” obtained from the clearance “C” and the axial length “L” of the sliding portion is the bearing located closest to the motor portion 10. The part 16a is set smaller than the other bearing parts 18a and 19a. For this reason, it is possible to most effectively suppress the tilting and swinging of the rotating shaft 11 when the electric motor unit 10 is driven, and the gap between the rotor 13 and the stator 14 when driving the electric motor unit 10 is made uniform. Can keep. Thereby, the rotation efficiency of the electric motor part 10 can be improved, and the noise and vibration which generate | occur | produce with the rotating shaft 11 rotating can be reduced.

  Further, since “C / L” is set large in the other bearing portions 18a and 19a, the alignment of the respective bearing portions 16a, 18a and 19a can be easily performed, and the assembly of the rotary compressor 4 is facilitated. Can be improved.

  Further, the “C / L” values of the bearing portions 16 a and 19 a located at both ends of the compression mechanism portion 12 are set to be smaller than the “C / L” values of the bearing portion 18 a located therebetween. For this reason, it is possible to suppress the tilt and swing of the rotating shaft 11 when the electric motor unit 10 is driven, and to keep the gap between the rotor 13 and the stator 14 uniform when the electric motor unit 10 is driven. it can. Thereby, the rotation efficiency of the electric motor part 10 can be improved, and the noise and vibration which generate | occur | produce with the rotating shaft 11 rotating can be reduced.

  Further, since “C / L” of the bearing portion 18a on the center side is set large, it is possible to allow more deformation and deflection of the rotating shaft 11 due to the compression load, and the reliability of the rotary compressor 4 can be increased. Durability can be increased.

  Comparing the rigidity of the sliding surfaces of the bearing portions 19a and 16a with the rotary shaft 11, the ring-side groove 40 is formed in the auxiliary bearing 19, so that the end portion side of the bearing portion 19a away from the motor portion 10 is provided. Is set to be smaller than the rigidity of the end portion side of the bearing portion 16a close to the electric motor portion 10. Thereby, in the sliding surface of the bearing part 16a located nearest to the electric motor part 10, since the rigidity of the end part side close to the electric motor part 10 is large, the inclination of the rotating shaft 11 and a whirling can be suppressed. On the other hand, on the sliding surface of the bearing portion 19a located away from the motor portion 10, the rigidity on the end side away from the motor portion 10 is small, so even if the rotation shaft 11 is inclined or swung, the rotation shaft 11 or An unreasonable force is prevented from acting on the bearing portion 19a, and the reliability and durability of the rotary compressor 4 can be improved.

  Next, the clearance “C ′” of the fitting portion between the inner peripheral surfaces of the rollers 22a, 22b, and 22c and the outer peripheral surfaces of the eccentric portions 21a, 21b, and 21c, and the inner peripheral surfaces of the rollers 22a, 22b, and 22c, The value of “C ′ / L ′” including the axial length “L ′” between the outer peripheral surfaces of the eccentric portions 21a, 21b, and 21c is the value of each of the bearing portions 16a, 18a, and 19a. It is set larger than the value of “C / L”. Therefore, when the rotation shaft 11 is tilted or bent, the rollers 22a, 22b, and 22c are restrained from tilting even when the rotation shaft 11 is tilted. For this reason, the end surfaces of the rollers 22a, 22b, and 22c are in contact with the main bearing 16, the first partition plate 17, the second partition plate 18, and the auxiliary bearing 19, and the tips of the blades 25a, 25b, and 25c are the rollers 22a, The contact with the outer peripheral surfaces of 22b and 22c is prevented from being stopped, and the reliability and durability of the rotary compressor 4 can be improved.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. This embodiment and its modifications are included in the scope of the present invention and the gist thereof, and are also included in the invention described in the claims and the equivalent scope thereof.

DESCRIPTION OF SYMBOLS 4 ... Rotary compressor, 5 ... Condenser, 6 ... Expansion device, 7 ... Evaporator, 9 ... Sealing case, 10 ... Electric motor part, 11 ... Rotating shaft, 12 ... Compression mechanism part, 15a, 15b, 15c ... Cylinder , 16 ... main bearing (closing member), 17 ... first partition plate (closing member), 18 ... second partition plate (closing member), 19 ... auxiliary bearing (closing member), 20a, 20b, 20c ... cylinder chamber, 21a, 21b. 21c ... eccentric part, 22a, 22b, 22c ... roller, 25a, 25b, 25c ... blade, 38 ... suction chamber, 39 ... compression chamber

Claims (5)

In the rotary compressor in which the electric motor unit and the compression mechanism unit driven by the rotary shaft connected to the electric motor unit are housed in a sealed case, and the working fluid is compressed by the compression mechanism unit,
The compression mechanism section includes at least three cylinders that are arranged in the axial direction of the rotary shaft and surround the rotary shaft, a closing member that closes both ends of each cylinder to form a cylinder chamber in each cylinder, and An eccentric portion provided in a portion of the rotating shaft located in each cylinder chamber, a roller fitted into the eccentric portion and rotated eccentrically in each cylinder chamber as the rotating shaft rotates, and in each cylinder chamber A blade that bisects the suction chamber and the compression chamber in the circumferential direction;
The rotating shaft is pivotally supported by bearing portions provided on at least three of the closing members,
The clearance of the sliding portion between the inner peripheral surface of the bearing portion and the outer peripheral surface of the rotating shaft is “C”, and the clearance of the sliding portion between the inner peripheral surface of the bearing portion and the outer peripheral surface of the rotating shaft is When the axial length is “L”, the “C / L” value of the bearing portion located closest to the motor portion is smaller than the “C / L” values of the other bearing portions. A rotary compressor characterized by that.   2. The rotary compressor according to claim 1, wherein a value of “C / L” of the bearing portion positioned at both ends is smaller than “C / L” of the bearing portion positioned therebetween.   The rigidity of the sliding portion of the bearing portion located farthest from the motor portion is such that the rigidity on the end portion side away from the motor portion in the sliding surface of the bearing portion located farthest from the motor portion is the sliding portion of the bearing portion located closest to the motor portion. The rotary compressor according to claim 1, wherein the rotary compressor is smaller than the rigidity on the end side close to.   The clearance of the fitting portion between the inner peripheral surface of the roller and the outer peripheral surface of the eccentric portion is “C ′”, and the shaft of the fitting portion between the inner peripheral surface of the roller and the outer peripheral surface of the eccentric portion The value of "C '/ L'" is larger than the value of "C / L" of each said bearing part when the length of a direction is set to "L '". The rotary compressor according to one item. The rotary compressor according to any one of claims 1 to 4, a condenser connected to the rotary compressor, an expansion device connected to the condenser, the expansion device, and the rotary type An refrigeration cycle apparatus comprising: an evaporator connected to the compressor.

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