Scroll electric compressor

Abstract

To provide a scroll electric compressor which enables reduction of the number of components and can be downsized in an axial direction.SOLUTION: In a scroll electric compressor, a rotor 24 has balance adjustment portions 58 which are provided at positions such that the balance adjustment portions 58 cancel a centrifugal force generated by a balance weight. An adjustment steel plate 51 has weight portions 52 each of which is formed at a position where a radial dimension of a first flow hole 511 is reduced compared to a radial dimension of a second flow hole 512 that overlaps the balance weight with respect to an axial direction. Further, the balance adjustment portion 58 is formed by stacking the weight portions 52 in the axial direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an electric scroll compressor. [Background technology]

[0002] For example, Patent Document 1 discloses a scroll-type electric compressor in which a balance weight is integrated with a drive shaft serving as a rotating shaft, and a rotor weight is integrated with an electric motor. When such a scroll-type electric compressor is in operation, centrifugal force caused by the revolution of the movable scroll serving as an orbiting scroll acts on the drive shaft, and centrifugal force generated by the balance weight also acts on the drive shaft. Furthermore, when the scroll-type compressor is in operation, centrifugal force generated by the rotor weight also acts on the drive shaft through the rotor. As a result, in the scroll-type electric compressor, the centrifugal force generated by the balance weight and the centrifugal force generated by the rotor weight cancel out the centrifugal force of the movable scroll acting on the drive shaft. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-36133 Summary of the Invention [Problem to be solved by the invention]

[0004] In a scroll-type electric compressor configured to offset the centrifugal force of the movable scroll acting on the drive shaft, it is desirable to reduce the number of parts and make the compressor more compact in the axial direction. [Means for solving the problem]

[0005] A scroll-type electric compressor for solving the above problems includes a rotating shaft, a motor including a rotor fixed to the rotating shaft and a cylindrical stator surrounding the rotor, a compression section driven by rotation of the rotating shaft to compress a fluid, and a housing accommodating the motor and the compression section, wherein the compression section includes a fixed scroll provided within the housing and an orbiting scroll that revolves with the rotation of the rotating shaft and forms a compression chamber between the fixed scroll and the orbiting scroll to compress the fluid, and the housing includes a motor housing accommodating the motor, a compression section housing accommodating the compression section, and a journal housing rotatably supporting the rotating shaft between the rotor and the orbiting scroll, and the rotating shaft includes a rotary shaft extending in a radial direction of the rotating shaft and extending forward in an axial direction of the rotating shaft. a balance weight is provided facing the rotor and the support housing, the rotor is formed by stacking a plurality of laminated steel plates in the axial direction, the rotor has a plurality of fluid circulation holes formed in the circumferential direction of the rotor that penetrate in the axial direction and through which the fluid flows, the fluid circulation holes are formed by stacking circulation holes formed in the laminated steel plates in the axial direction, the rotor has a balance adjustment portion provided at a position that cancels out the centrifugal force generated by the balance weight, the laminated steel plates have a weight portion formed at a position where the radial dimension of the circulation hole is smaller than the radial dimension of the circulation hole that overlaps with the balance weight in the axial direction, and the balance adjustment portion is formed by stacking the weight portion in the axial direction.

[0006] According to this, when the scroll-type electric compressor is operating, centrifugal force caused by the revolution of the orbiting scroll acts on the rotating shaft, and centrifugal force generated by the balance weight also acts on the rotating shaft. Furthermore, centrifugal force generated by the balance adjustment unit also acts on the rotating shaft through the rotor. As a result, in the scroll-type electric compressor, the centrifugal force of the orbiting scroll acting on the rotating shaft can be offset by the centrifugal force generated by the balance weight and the centrifugal force generated by the balance adjustment unit.

[0007] The rotor having the balance adjustment portion is provided by adjusting the radial dimensions of the through holes in the laminated steel plates to adjust the weight of the weight portion. In other words, the balance adjustment of the rotor weight using the balance adjustment portion can be performed simply by adjusting the radial dimensions of the through holes. Therefore, the balance adjustment of the rotor can be performed without providing a separate component such as a weight to the rotor. Therefore, compared to a case where a separate component is added to the axial end face of the rotor to perform balance adjustment of the rotor, the number of rotor parts can be reduced and the rotor can be made smaller in the axial direction.

[0008] In a scroll-type electric compressor, the rotor is formed integrally with the rotating shaft by shrink fitting, the fluid circulation holes are elongated holes extending in an arc shape in the circumferential direction of the rotor, and inner surfaces of the fluid circulation holes extend along concentric circles centered on the axis of the rotating shaft, and the fluid circulation holes located radially inward of the balance adjustment portion may be located radially inward compared to the fluid circulation holes that overlap with the balance weight in the axial direction.

[0009] According to this, when the rotor is integrated with the rotating shaft by shrink fitting, the rotor is heated. At this time, the rotor is likely to expand in the radial direction of the rotor due to the presence of the fluid circulation holes. Therefore, even if the size of the fluid circulation holes is reduced in the radial direction of the rotor, the rotor and the rotating shaft can be easily integrated.

[0010] In the scroll-type electric compressor, the balance adjustment portion may be provided by stacking the weight portion over the entire axial direction of the rotor. This allows the weight of the rotor to be balanced in the axial direction, making it easy to manufacture a balanced rotor.

[0011] In the scroll-type electric compressor, the balance adjustment portion may be provided by stacking the weight portion on a part of the rotor in the axial direction. This allows the weight balance of the rotor to be varied in the axial direction, thereby widening the range of balance adjustment possible with the rotor. [Effects of the Invention]

[0012] The scroll type electric compressor of the present invention can reduce the number of parts and make it smaller in size in the axial direction. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a cross-sectional view showing a scroll-type electric compressor according to a first embodiment. [Figure 2] FIG. 2 is an exploded perspective view showing the rotor. [Figure 3] FIG. 3 is a view of the rotor as viewed in the axial direction. [Figure 4] FIG. 4 is a view of the rotor body as viewed in the axial direction. [Figure 5] FIG. 5 is a cross-sectional view showing a rotor according to the second embodiment. [Figure 6] FIG. 6 is a diagram showing a laminated steel sheet according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] [First embodiment] A first embodiment of a scroll type electric compressor will be described below with reference to FIGS.

[0015] <Overall scroll type electric compressor> 1, the scroll-type electric compressor 10 includes a housing 11, a rotating shaft 15, a compression unit 25, a motor 22, and a balance weight 33. The rotating shaft 15, the compression unit 25, the motor 22, and the balance weight 33 are each accommodated inside the housing 11.

[0016] <Housing> The housing 11 includes a motor housing 12, a support housing 13, and a compression unit housing 14. The motor housing 12, the support housing 13, and the compression unit housing 14 are made of metal, such as aluminum.

[0017] The motor housing 12 has an end wall 12a and a peripheral wall 12b that extends cylindrically from the outer periphery of the end wall 12a toward the journal housing 13. The axial direction of the peripheral wall 12b coincides with the axial direction of the rotary shaft 15. An internally threaded hole 12c is formed in the peripheral wall 12b on the side opposite the end wall 12a. Furthermore, an intake port 12e is formed in the peripheral wall 12b on the side facing the end wall 12a to draw in a refrigerant as a fluid.

[0018] The motor housing 12 has a boss 12d protruding from the inner surface of the end wall 12a. A first end of the rotary shaft 15 is inserted into the boss 12d, and a bearing 16 is provided between the inner peripheral surface of the boss 12d and the outer peripheral surface of the first end of the rotary shaft 15.

[0019] The support housing 13 has a disk-shaped flange 19, a cylindrical portion 18 that protrudes from the inner peripheral edge of the flange 19, and an end wall 17 that extends in a disk shape from the inner peripheral edge of the cylindrical portion 18. The outer peripheral portion of the flange 19 is sandwiched from both sides in the axial direction of the rotary shaft 15 by the motor housing 12 and the compression portion housing 14. A bolt insertion hole 19a is formed in part of the outer peripheral portion of the flange 19.

[0020] The second end of the rotary shaft 15 is inserted through the center of the end wall 17. A bearing 21 is provided between the outer peripheral surface of the second end of the rotary shaft 15 and the inner peripheral surface of the cylindrical portion 18. The rotary shaft 15 is rotatably supported in the housing 11 via the bearings 16 and 21. The rotary shaft 15 has an eccentric shaft 32 integrally formed therewith, which protrudes from an end face 15a at the second end. The eccentric shaft 32 protrudes toward the compression portion 25 from a position eccentric with respect to the axis L1 of the rotary shaft 15.

[0021] Motor housing 12 and support housing 13 define a motor accommodating chamber 20. Motor 22 is housed in motor accommodating chamber 20 and is also housed in housing 11. Refrigerant is drawn into motor accommodating chamber 20 through suction port 12e.

[0022] The compression unit housing 14 has an end wall 14a and a peripheral wall 14b that extends cylindrically from the outer peripheral edge of the end wall 14a toward the support housing 13. The axial direction of the peripheral wall 14b coincides with the axial direction of the rotary shaft 15. A bolt insertion hole 14c is formed in the peripheral wall 14b on the side opposite the end wall 14a. A bolt B1 that passes through the bolt insertion hole 14c of the compression unit housing 14 and the bolt insertion hole 19a of the flange 19 is screwed into the female threaded hole 12c of the motor housing 12. In this way, the motor housing 12, the support housing 13, and the compression unit housing 14 are connected to form the housing 11.

[0023] A plurality of first grooves 36 are formed in a portion of the inner circumferential surface of the peripheral wall 12b of the motor housing 12. Furthermore, first holes 37 communicating with each of the first grooves 36 are formed in the outer periphery of the flange 19 of the journal housing 13. Furthermore, second grooves 38 communicating with each of the first holes 37 are formed in a portion of the inner circumferential surface of the peripheral wall 14b of the compression unit housing 14. Note that for convenience of illustration, FIG. 1 shows only one each of the first groove 36, first hole 37, and second groove 38.

[0024] In the scroll-type electric compressor 10, the refrigerant sucked into the motor accommodating chamber 20 from the suction port 12e passes through the motor 22, then passes through the first groove 36, the first hole 37, and the second groove 38, and is sucked into the compression section 25.

[0025] A discharge chamber 40 is defined inside the housing 11. The discharge chamber 40 is defined by the compression section housing 14 and the compression section 25. The discharge chamber 40 communicates with a discharge port 27h of the compression section 25. Refrigerant compressed in the compression section 25 is discharged into the discharge chamber 40 via the discharge port 27h.

[0026] <Motor> The motor 22 is accommodated in the motor housing 12. The motor 22 rotates the rotary shaft 15. The motor 22 includes a rotor 24 fixed to the rotary shaft 15 and a cylindrical stator 23 surrounding the rotor 24. The rotor 24 rotates integrally with the rotary shaft 15. The stator 23 surrounds the rotor 24 in the circumferential direction of the rotary shaft 15 and is fixed to the peripheral wall 12b.

[0027] The stator 23 has a cylindrical stator core 23a fixed to the inner circumferential surface of the circumferential wall 12b of the motor housing 12, and a coil 23b wound around the stator core 23a. Power controlled by a drive circuit (not shown) is supplied to the coil 23b, causing the rotor 24 to rotate, and the rotary shaft 15 to rotate integrally with the rotor 24. The rotor 24 will be described in detail later.

[0028] <Compression section> The compression section 25 is driven by the rotation of the rotary shaft 15 to compress the refrigerant. The compression section 25 has a fixed scroll 27 provided in the housing 11 and an orbiting scroll 28 that revolves with the rotation of the rotary shaft 15 and forms a compression chamber 29 for compressing the refrigerant between the fixed scroll 27 and the orbiting scroll 28. The fixed scroll 27 and the orbiting scroll 28 are disposed inside the peripheral wall 14b of the compression section housing 14. Therefore, the compression section housing 14 accommodates the compression section 25.

[0029] The fixed scroll 27 is fixed to the compression section housing 14 and disposed inside the housing 11. The fixed scroll 27 has a fixed base plate 27a, a fixed spiral wall 27b, and a fixed outer peripheral wall 27c. The fixed base plate 27a is disk-shaped. A discharge port 27h is formed in the center of the fixed base plate 27a. The fixed spiral wall 27b stands up from the fixed base plate 27a toward the journal housing 13. The fixed outer peripheral wall 27c stands up in a cylindrical shape from the outer periphery of the fixed base plate 27a toward the journal housing 13. The fixed outer peripheral wall 27c surrounds the fixed spiral wall 27b. A suction port 27d is provided in the fixed outer peripheral wall 27c.

[0030] The orbiting scroll 28 is provided inside the compression section housing 14 and is connected to the rotary shaft 15. The orbiting scroll 28 has an orbiting base plate 28a and an orbiting spiral wall 28b. The orbiting base plate 28a is disk-shaped. The orbiting base plate 28a faces the fixed base plate 27a and the support housing 13 in the axial direction of the rotary shaft 15. Therefore, the support housing 13 rotatably supports the rotary shaft 15 between the rotor 24 and the orbiting scroll 28. The orbiting spiral wall 28b stands upright from the orbiting base plate 28a toward the fixed base plate 27a. The orbiting spiral wall 28b meshes with the fixed spiral wall 27b. The orbiting spiral wall 28b is located inside the fixed outer peripheral wall 27c. The tip surface of the fixed spiral wall 27b contacts the orbiting base plate 28a, and the tip surface of the orbiting spiral wall 28b contacts the fixed base plate 27a. A compression chamber 29 for compressing the refrigerant is defined by the fixed base plate 27a, the fixed spiral wall 27b, the swirling base plate 28a, and the swirling spiral wall 28b.

[0031] The swivel base plate 28a has a cylindrical boss portion 28c on its end face 28e opposite the fixed base plate 27a. The axial direction of the boss portion 28c coincides with the axial direction of the rotary shaft 15. A plurality of circular recesses 28d are formed around the boss portion 28c on the end face 28e of the swivel base plate 28a. The recesses 28d are arranged at predetermined intervals in the circumferential direction of the rotary shaft 15. An annular ring member 28f is fitted into each recess 28d. A pin 31 to be inserted into each ring member 28f is protruded from the end face 13e of the support housing 13 on the compression section housing 14 side.

[0032] The fixed base plate 27a has a valve mechanism 27v attached to the surface opposite to the orbiting scroll 28. The valve mechanism 27v opens and closes the discharge port 27h. The eccentric shaft 32 protruding from the end face 15a of the rotating shaft 15 protrudes toward the orbiting scroll 28 and is inserted into the boss portion 28c. The orbiting scroll 28 is supported on the eccentric shaft 32 via a bushing 34 and a bearing 35 so as to be rotatable relative to the eccentric shaft 32. The rotation of the rotating shaft 15 is transmitted to the orbiting scroll 28 via the eccentric shaft 32, the bushing 34, and the bearing 35. As a result, the orbiting scroll 28 attempts to rotate, but contact between the pins 31 and the inner circumferential surfaces of the ring members 28f prevents the orbiting scroll 28 from rotating and allows only the orbital motion of the orbiting scroll 28. As a result, the orbiting scroll 28 revolves while the orbiting spiral wall 28b is in contact with the fixed spiral wall 27b, reducing the volume of the compression chamber 29 and compressing the refrigerant.

[0033] In the scroll-type electric compressor 10, the refrigerant drawn into the motor housing chamber 20 through the suction port 12e passes through the motor 22, the first groove 36, the first hole 37, and the second groove 38, and is drawn into a suction chamber (not shown) through the suction port 27d. The refrigerant drawn into the suction chamber is compressed in the compression chamber 29 by the orbital motion of the orbiting scroll 28. The refrigerant compressed in the compression chamber 29 pushes aside the valve mechanism 27v and is discharged into the discharge chamber 40 through the discharge port 27h.

[0034] <Balance weight> The balance weight 33 is fixed to the rotary shaft 15 and rotates integrally with the rotary shaft 15. The balance weight 33 faces the rotor 24 and the support housing 13 in the axial direction of the rotary shaft 15. The balance weight 33 is disposed on the rotary shaft 15 at a position opposite the eccentric shaft 32 across the axis L1, and is disposed eccentrically from the axis L1. The balance weight 33 has a substantially rectangular plate shape extending in the radial direction of the rotary shaft 15. The balance weight 33 has a base end 33a, an inclined portion 33b, and a tip end 33c. The base end 33a is fixed to the rotary shaft 15. The inclined portion 33b extends inclined from the base end 33a toward the support housing 13. The tip end 33c extends from the inclined portion 33b approximately perpendicular to the radial direction of the rotary shaft 15. The inclined portion 33 b and the tip portion 33 c of the balance weight 33 extend away from the eccentric shaft 32 in the radial direction of the rotary shaft 15 .

[0035] The balance weight 33 offsets the centrifugal force acting on the orbiting scroll 28 when the orbiting scroll 28 revolves, thereby reducing the amount of imbalance in the orbiting scroll 28. The shape of the balance weight 33 can be changed to any shape as long as it can offset the centrifugal force acting on the orbiting scroll 28 when the orbiting scroll 28 revolves.

[0036] <Rotor> 1 and 3, the rotor 24 has a rotor body 50, a pair of retaining plates 71, a plurality of connecting pins 73, and a plurality of permanent magnets 24a. The axial direction of the rotor 24 and the rotor body 50 coincides with the axial direction of the rotating shaft 15, and the radial direction of the rotor 24 and the rotor body 50 coincides with the radial direction of the rotating shaft 15.

[0037] The rotor body 50 is formed with a shaft hole 50a through which the rotating shaft 15 is inserted, a plurality of magnet holes 50b through which the permanent magnets 24a are inserted, a plurality of pin holes 50c through which the connecting pins 73 are inserted, and a plurality of fluid circulation holes 60 through which the refrigerant flows. Each of the shaft hole 50a, magnet holes 50b, pin holes 50c, and fluid circulation holes 60 penetrates the rotor body 50 in the axial direction, and multiple holes are formed in the circumferential direction of the rotor 24.

[0038] As shown in Figures 2 and 3, the shaft hole 50a is formed in the center of the rotor body 50. The multiple magnet holes 50b are formed in the peripheral edge of the rotor body 50. The multiple magnet holes 50b are formed at equal intervals in the circumferential direction of the rotor body 50. The number of permanent magnets 24a and the number of magnet holes 50b provided in the rotor body 50 can be changed as appropriate. The multiple pin holes 50c are formed radially inward of the rotor body 50 from the portion of the rotor body 50 where the magnet holes 50b are formed. The multiple pin holes 50c are formed at equal intervals in the circumferential direction of the rotor body 50. The number of pin holes 50c formed in the rotor body 50 can be changed as appropriate depending on the number of connecting pins 73.

[0039] The fluid circulation holes 60 include two first fluid circulation holes 61 and three second fluid circulation holes 62. In Fig. 3, the outer shape of the second fluid circulation holes 62 matches the outer shape of an introduction hole 72 of a holding plate 71, which will be described later, and therefore the second fluid circulation holes 62 are indicated by dashed lines. The two first fluid circulation holes 61 do not overlap the base end 33a of the balance weight 33 in the axial direction of the rotating shaft 15. Furthermore, the middle second fluid circulation hole 62 of the three second fluid circulation holes 62 entirely overlaps the inclined portion 33b of the balance weight 33 in the axial direction of the rotating shaft 15, and the two second fluid circulation holes 62 on either side partially overlap the inclined portion 33b of the balance weight 33.

[0040] The two first fluid circulation holes 61 and the three second fluid circulation holes 62 are formed at equal intervals around the axial hole 50a. An axial view is when the rotor body 50 is viewed along the axial direction. When viewed in the axial direction, each of the first fluid circulation holes 61 and the second fluid circulation holes 62 is an elongated hole extending in an arc shape in the circumferential direction of the rotor body 50. Furthermore, each of the first fluid circulation holes 61 and the second fluid circulation holes 62 penetrates the entire rotor body 50 in the axial direction.

[0041] Each first fluid passage 61 is defined by a first inner arcuate surface 61a, which is the inner circumferential surface of the first fluid passage 61, a first outer arcuate surface 61b, and a pair of first side surfaces 61c. The first inner arcuate surface 61a is located radially inward of the first outer arcuate surface 61b and has a smaller dimension in the circumferential direction of the rotor body 50 than the first outer arcuate surface 61b. One of the pair of first side surfaces 61c connects one ends of the first inner arcuate surface 61a and the first outer arcuate surface 61b, and the other of the pair of first side surfaces 61c connects the other ends of the first inner arcuate surface 61a and the first outer arcuate surface 61b.

[0042] Each second fluid flow hole 62 has a second inner arcuate surface 62a, a second outer arcuate surface 62b, and a pair of second side surfaces 62c. The second inner arcuate surface 62a is located radially inward of the second outer arcuate surface 62b and has a smaller dimension in the circumferential direction of the rotor body 50 than the second outer arcuate surface 62b. One of the pair of second side surfaces 62c connects one ends of the second inner arcuate surface 62a and the second outer arcuate surface 62b, and the other of the pair of second side surfaces 62c connects the other ends of the second inner arcuate surface 62a and the second outer arcuate surface 62b.

[0043] When viewed in the axial direction of the rotor body 50, the first inner arcuate surface 61a and the second inner arcuate surface 62a are located on the arc of a first imaginary circle C1. The first imaginary circle C1 is a concentric circle of the shaft hole 50a whose center is the axis L1 of the rotary shaft 15.

[0044] Furthermore, when viewed in the axial direction of the rotor body 50, the three second outer arc surfaces 62b are located on the arc of a second imaginary circle C2, which has a larger diameter than the first imaginary circle C1. The second imaginary circle C2 is concentric with the shaft hole 50a and the first imaginary circle C1, and is centered on the axis L1 of the rotating shaft 15. The two first fluid circulation holes 61 are located radially inward of the second imaginary circle C2. The two first fluid circulation holes 61 and the three second fluid circulation holes 62 are located on the arc of the first imaginary circle C1.

[0045] The radial dimension of the first side surface 61c of the rotor body 50 is smaller than the radial dimension of the second side surface 62c of the rotor body 50. Therefore, the circumferential dimension of the first outer arcuate surface 61b of the rotor body 50 is smaller than the circumferential dimension of the second outer arcuate surface 62b of the rotor body 50.

[0046] In the rotor body 50, a portion radially outward of the first fluid circulation holes 61 forms a balance adjustment portion 58. The balance adjustment portion 58 is formed in the rotor body 50 by making the radial dimension of the first fluid circulation holes 61 in the rotor 24 smaller than the radial dimension of the second fluid circulation holes 62. In other words, the balance adjustment portion 58 is formed at a position where the radial dimension of the first fluid circulation holes 61 is smaller than the radial dimension of the second fluid circulation holes 62 that overlap with the balance weight 33 in the axial direction.

[0047] The radial dimension of the balance adjustment portion 58 is greater than the dimension of the portion outer than the second fluid circulation holes 62. Therefore, the weight of the balance adjustment portion 58 is greater than the weight of the portion of the rotor body 50 radially outer than the second fluid circulation holes 62. In addition, the first fluid circulation holes 61 located radially inward of the balance adjustment portion 58 are located radially inward compared to the other second fluid circulation holes 62.

[0048] The center of gravity of the rotor body 50 is located radially closer to the two first fluid communication holes 61 than the axis L1 of the rotary shaft 15. More specifically, the center of gravity of the rotor body 50 is located on the opposite side of the axis L1 from the inclined portion 33b and the tip end portion 33c of the balance weight 33. As a result, the rotor 24 has a balance adjustment unit 58 provided at a position in the circumferential direction of the rotor 24 that controls the centrifugal force generated by the balance weight 33.

[0049] 2, the rotor body 50 of the rotor 24 is formed by stacking a plurality of adjustment steel plates 51 as laminated steel plates in the axial direction of the rotating shaft 15. The radial direction of the adjustment steel plates 51 coincides with the radial direction of the rotating shaft 15.

[0050] 4, the adjustment steel plate 51 is formed with a shaft hole forming hole 51a that forms the shaft hole 50a, a magnet hole forming hole 51b that forms the magnet hole 50b, a pin hole forming hole 51c that forms the pin hole 50c, and a circulation hole 51d that forms the fluid circulation hole 60. Each of the shaft hole forming hole 51a, the magnet hole forming hole 51b, the pin hole forming hole 51c, and the circulation hole 51d penetrates the adjustment steel plate 51 in the plate thickness direction.

[0051] The shaft hole forming hole 51a is formed in the center of the adjustment steel plate 51. The multiple magnet hole forming holes 51b are formed in the peripheral edge of the adjustment steel plate 51. The multiple magnet hole forming holes 51b are formed at equal intervals in the circumferential direction of the adjustment steel plate 51. The multiple pin hole forming holes 51c are formed radially inward of the adjustment steel plate 51 from the portion where the magnet hole forming holes 51b are formed. The multiple pin hole forming holes 51c are formed at equal intervals in the circumferential direction of the adjustment steel plate 51.

[0052] The through holes 51d include two first through holes 511 and three second through holes 512. The two first through holes 511 and the three second through holes 512 are formed at equal intervals around the shaft hole forming hole 51a. When the adjustment steel plate 51 is viewed in the plate thickness direction, each of the first through holes 511 and the second through holes 512 is an elongated hole extending in an arc shape in the circumferential direction of the adjustment steel plate 51.

[0053] Each first through hole 511 has a first inner edge portion 511a that forms the first inner arcuate surface 61a, a first outer edge portion 511b that forms the first outer arcuate surface 61b, and first side edge portions 511c that form each of a pair of first side surfaces 61c. The first inner edge portion 511a is located more inward in the radial direction of the adjustment steel plate 51 than the first outer edge portion 511b, and has a smaller dimension in the circumferential direction of the adjustment steel plate 51 than the first outer edge portion 511b. One of the pair of first side edge portions 511c connects one end of the first inner edge portion 511a and one end of the first outer edge portion 511b, and the other of the pair of first side edge portions 511c connects the other ends of the first inner edge portion 511a and one end of the first outer edge portion 511b. The first fluid communication holes 61 are formed by stacking the first communication holes 511 formed in the adjustment steel plates 51 in the axial direction of the rotary shaft 15 .

[0054] Each second through hole 512 has a second inner edge portion 512a that forms the second inner arcuate surface 62a, a second outer edge portion 512b that forms the second outer arcuate surface 62b, and second side edge portions 512c that form each of a pair of second side surfaces 62c. The second inner edge portion 512a is located radially inward of the second outer edge portion 512b and has a smaller dimension in the circumferential direction of the adjustment steel plate 51 than the second outer edge portion 512b. One of the pair of second side edge portions 512c connects one end of the second inner edge portion 512a and one end of the second outer edge portion 512b, and the other of the pair of second side edge portions 512c connects the other ends of the second inner edge portion 512a and one end of the second outer edge portion 512b. The second fluid flow holes 62 are formed by stacking the second flow holes 512 formed in the adjustment steel plate 51 in the axial direction of the rotary shaft 15 .

[0055] In the adjustment steel plate 51, the radial dimension N1 from the outer edge of the adjustment steel plate 51 to the first outer edge 511b is greater than the radial dimension N2 from the outer edge of the adjustment steel plate 51 to the second outer edge 512b. Therefore, the portion of the adjustment steel plate 51 where the two first through holes 511 are formed in the circumferential direction is heavier than the other portions. This heavier portion forms a weight portion 52 of the adjustment steel plate 51. The weight portion 52 is formed in the adjustment steel plate 51 at a position where the radial dimension of the first through hole 511 is smaller than the radial dimension of the second through hole 512 that overlaps with the balance weight 33 in the axial direction. Therefore, the adjustment steel plate 51 has the weight portion 52 formed in a position where the radial dimension of the first through hole 511 is smaller than the radial dimension of the second through hole 512 that overlaps with the balance weight 33 in the axial direction.

[0056] 4 shows a case where second through holes 512 are formed instead of the first through holes 511. The first through holes 511 are formed by blocking a portion of the second through holes 512. In other words, the first through holes 511 are formed with a larger dimension in the radial direction of the adjustment steel plate 51 than the second through holes 512.

[0057] The weight portions 52 of the adjustment steel plates 51 are stacked over the entire axial direction of the rotor body 50 to form the balance adjustment portion 58. Therefore, the adjustment steel plates 51 have the weight portions 52, and the balance adjustment portion 58 is formed by stacking the weight portions 52 over the entire axial direction of the rotor 24.

[0058] In the adjustment steel plate 51, by adjusting the size of the dimension N1 and thus the radial dimension of the first communication hole 511, the weight of the weight portion 52 can be adjusted, and thus the weight of the balance adjustment portion 58 can be adjusted. Adjusting the weight of the balance adjustment portion 58 adjusts the position of the center of gravity of the rotor body 50. As the dimension N1 is made smaller, the radial dimensions of the first communication hole 511 and the first fluid communication hole 61 increase, thereby reducing the weight of the weight portion 52 and therefore the balance adjustment portion 58. In other words, as the dimension N1 is made smaller, the position of the center of gravity of the rotor body 50 can be brought closer to the axis L1. Furthermore, by matching the dimension N1 with the dimension N2, all five fluid communication holes 60 have the same size, eliminating imbalance in the adjustment steel plate 51.

[0059] Conversely, the larger the dimension N1, the smaller the radial dimensions of the first communication holes 511 and the first fluid communication holes 61, and therefore the weight of the weight portion 52 and therefore the balance adjustment portion 58 increases. In other words, the larger the dimension N1, the farther the position of the center of gravity of the rotor body 50 can be moved from the axis L1. Then, by adjusting the magnitude of the dimension N1 and the position of the center of gravity, the balance adjustment in weight with the balance weight 33 can be performed.

[0060] Specifically, the weight and the position of the center of gravity of the balance adjustment unit 58 are adjusted so that the centrifugal force generated by the balance weight 33 can be offset by the centrifugal force generated by the balance adjustment unit 58. The weight and the position of the center of gravity of the balance adjustment unit 58 are determined by adjusting the dimension N1, and the value of the dimension N1 is adjusted taking into consideration the weight of the adjustment steel plate 51, the weight of the balance weight 33, the weight of the holding plate 71, the weight of the connecting pin 73, and the weight of the permanent magnet 24a.

[0061] 2 and 3, each of the pair of holding plates 71 is formed of a disk-shaped metal plate. One holding plate 71 is disposed on a first axial end face of the rotor body 50, and the other holding plate 71 is disposed on a second axial end face of the rotor body 50.

[0062] Coupling pins 73 are inserted through the pair of holding plates 71 and each pin hole 50c of the rotor body 50. Both ends of each coupling pin 73 are crimped, thereby sandwiching the rotor body 50 between the pair of holding plates 71. A permanent magnet 24a is inserted through each magnet hole 50b and is adhered to the rotor body 50 with an adhesive.

[0063] Each holding plate 71 has a through hole 71a formed therein that coincides with the shaft hole 50a of the rotor body 50. The rotary shaft 15 is inserted through the through hole 71a and the shaft hole 50a of each holding plate 71. Five introduction holes 72 are formed in each holding plate 71. Two of the five introduction holes 72 are positioned to overlap with the two first fluid circulation holes 61, and the remaining three are positioned to overlap with the three second fluid circulation holes 62.

[0064] Each introduction hole 72 has an inner diameter edge 72a, an outer diameter edge 72b, and a pair of edges 72c. The inner diameter edge 72a is located radially inward of the holding plate 71 relative to the outer diameter edge 72b, and has a smaller dimension in the circumferential direction of the holding plate 71 than the outer diameter edge 72b. One of the pair of edges 72c connects one end of the inner diameter edge 72a and one end of the outer diameter edge 72b, and the other of the pair of edges 72c connects the other ends of the inner diameter edge 72a and one end of the outer diameter edge 72b.

[0065] The circumferential dimension of an inner diameter edge 72a of the retaining plate 71 is the same as the dimensions of the first inner arcuate surface 61a and the second inner arcuate surface 62a. The circumferential dimension of an outer diameter edge 72b of the retaining plate 71 is the same as the dimension of the second outer arcuate surface 62b. The radial dimension of an edge 72c of the retaining plate 71 is larger than the first side surface 61c and the same as the dimension of the second side surface 62c. Therefore, as shown in FIG. 3 , the first fluid circulation hole 61 opens in a part of the retaining plate 71, radially inward of the introduction hole 72 of the retaining plate 71. The second fluid circulation hole 62 opens over the entire surface of the introduction hole 72.

[0066] Therefore, the introduction holes 72 overlapping with the first fluid circulation holes 61 and the second fluid circulation holes 62 open the first fluid circulation holes 61 and the second fluid circulation holes 62 over the entire surfaces. The pair of holding plates 71 have a uniform weight balance in the circumferential and radial directions. Therefore, even when the rotor body 50 is sandwiched between the pair of holding plates 71, the weight imbalance caused by the rotor body 50 is maintained.

[0067] The rotor 24 is provided integrally with the rotating shaft 15 by shrink-fitting the rotating shaft 15 into the shaft hole 50a and the through-hole 71a. At this time, the rotor body 50 and the rotating shaft 15 are positioned so that the first fluid communication hole 61 side of the rotor body 50 is located on the opposite side of the balance weight 33 across the axis L1.

[0068] [Operation of the embodiment] The operation of this embodiment will be described. When the scroll-type electric compressor 10 is in operation, centrifugal force caused by the revolution of the orbiting scroll 28 acts on the rotating shaft 15. Meanwhile, a balance weight 33 is integrally provided on the rotating shaft 15. As a result, when the scroll-type electric compressor 10 is in operation, the centrifugal force generated by the balance weight 33 acts on the rotating shaft 15. Furthermore, the rotor 24 has a balance adjustment unit 58 provided on the rotor body 50. As a result, when the scroll-type electric compressor 10 is in operation, the centrifugal force generated by the balance adjustment unit 58 also acts on the rotating shaft 15 through the rotor 24. As a result, in the scroll-type electric compressor 10, the centrifugal force of the orbiting scroll 28 acting on the rotating shaft 15 can be offset by the centrifugal force generated by the balance weight 33 and the centrifugal force generated by the balance adjustment unit 58.

[0069] [Advantages of the first embodiment] According to the above embodiment, the following effects can be obtained. (1-1) In the rotor body 50, by adjusting the weight of the weight portion 52 by adjusting the radial dimension of the first through hole 511 of the adjustment steel plate 51, it is possible to provide the balance adjustment portion 58 to the rotor 24 in which the adjustment steel plates 51 are stacked. In other words, the balance adjustment of the rotor 24 using the balance adjustment portion 58 can be performed simply by adjusting the radial dimension of the adjustment steel plate 51. Therefore, the balance adjustment of the rotor 24 can be performed without providing a separate member such as a weight to the rotor 24. Therefore, compared to the case where the balance adjustment of the rotor 24 is performed by adding a separate member to the end face of the rotor 24 in the axial direction, the number of parts of the rotor 24 can be reduced and the rotor 24 can be made smaller in the axial direction.

[0070] (1-2) The balance adjustment portion 58 is provided in the rotor 24 by forming the first fluid circulation holes 61 and the second fluid circulation holes 62, which have different radial dimensions, in the rotor body 50. That is, the balance adjustment portion 58 is formed by filling the portion of the rotor body 50 where the second fluid circulation hole 62 is to be formed with the weight portion 52 of the adjustment steel plate 51. Therefore, if the second fluid circulation hole 62 is formed at the position of the first fluid circulation hole 61, the balance adjustment portion 58 can be formed by effectively utilizing the portion that would otherwise be discarded. Therefore, the scroll-type electric compressor 10 can reduce the number of parts of the rotor 24 while reducing the material yield of the rotor 24, and can also reduce the axial size of the rotor 24.

[0071] (1-3) The first fluid communication holes 61 are holes through which the refrigerant flows when the refrigerant is drawn into the compression section 25. In the scroll-type electric compressor 10, the balance adjustment section 58 can be provided in the rotor 24 by adjusting the size of the first fluid communication holes 61, that is, by adjusting the size of the first communication holes 511 in the radial direction. Therefore, the scroll-type electric compressor 10 can effectively offset the centrifugal force of the orbiting scroll 28 acting on the rotary shaft 15 by effectively utilizing the existing configuration.

[0072] (1-4) The first fluid circulation hole 61, together with the second fluid circulation hole 62, is disposed on the first imaginary circle C1. Therefore, the first fluid circulation hole 61 is disposed close to the shaft hole 50a in the radial direction of the rotor body 50. When the rotor body 50 is integrated with the rotating shaft 15 by shrink fitting, the rotor body 50 is heated. At this time, the rotor body 50 is likely to expand in the radial direction of the rotor 24 due to the presence of the fluid circulation holes 60, including the first fluid circulation hole 61. Therefore, even if the radial dimension of the first fluid circulation hole 61 is smaller than that of the second fluid circulation hole 62, the rotor 24 and the rotating shaft 15 can be easily integrated using the first fluid circulation hole 61.

[0073] (1-5) The balance adjustment portion 58 is provided over the entire axial length of the rotor 24. This allows the weight of the rotor 24 to be balanced axially, making it easy to manufacture a balanced rotor 24.

[0074] [Second embodiment] Next, a second embodiment of a scroll-type electric compressor will be described with reference to Figures 5 and 6. Note that the second embodiment has a configuration in which only the rotor body 50 of the first embodiment is modified, and therefore detailed description of similar parts will be omitted.

[0075] 5, the rotor body 50 is formed by laminating a plurality of adjustment steel plates 51 of the first embodiment and laminated steel plates 82 that are different from the adjustment steel plates 51. The radial direction of the laminated steel plates 82 coincides with the radial direction of the rotating shaft 15.

[0076] As shown in FIG. 6 , five second through holes 512 are formed in the laminated steel plate 82, in addition to the second through holes 512 formed in the adjustment steel plate 51. The five second through holes 512 are formed at equal intervals in the circumferential direction of the laminated steel plate 82. The radial dimension M from the outer edge of the laminated steel plate 82 to the second outer edge 512b is the same as the radial dimension N2 from the outer edge of the adjustment steel plate 51 to the second outer edge 512b. The radial outer dimensions M of the five second through holes 512 are all the same. Therefore, the laminated steel plate 82 does not include a weight portion 52. The center of gravity of the laminated steel plate 82 is located on the center P of the laminated steel plate 82.

[0077] 5, the rotor body 50 is formed by stacking a plurality of adjustment steel plates 51 and a plurality of laminated steel plates 82 in the axial direction. The adjustment steel plates 51 are stacked from a first axial end face to a second end face side of the axial center. The laminated steel plates 82 are stacked from a second end face side of the axial center to the second end face.

[0078] The fluid flow hole 60 has a third fluid flow hole 63 formed by a first flow hole 511 of the adjustment steel plate 51 and a second flow hole 512 of the laminated steel plate 82, and a second fluid flow hole 62 formed by the second flow hole 512 of the adjustment steel plate 51 and the second flow hole 512 of the laminated steel plate 82.

[0079] Therefore, in the rotor body 50, the portion where the adjustment steel plates 51 are stacked is provided with a balance adjustment portion 58 by the weight portion 52, and is heavier than the portion where the laminated steel plates 82 are stacked. Therefore, the rotor body 50 has a different weight balance in both the axial and circumferential directions. The balance adjustment portion 58 is provided by stacking the weight portion 52 on a portion of the rotor 24 in the axial direction.

[0080] [Effects of the second embodiment] Therefore, according to the second embodiment, in addition to the effects (1-1) to (1-4) described in the first embodiment, the following effects can be obtained.

[0081] (2-1) The balance adjustment portion 58 is provided at a portion of the axial direction of the rotor 24. This allows the weight balance of the rotor 24 to be varied in the axial direction as well. This allows for a wider range of balance adjustment using the rotor 24.

[0082] (2-2) The rotor body 50 is formed by combining an adjustment steel plate 51 and a laminated steel plate 82. The laminated steel plate 82 has five second through holes 512 formed at equal intervals in the circumferential direction, and therefore does not have a weight portion 52. Therefore, the laminated steel plate 82 is an existing steel plate used to manufacture a rotor 24 that does not have a balance adjustment portion 58. Therefore, by combining the existing laminated steel plate 82 with the adjustment steel plate 51, the weight balance of the rotor 24 can be adjusted.

[0083] [Example of change] This embodiment can be implemented with the following modifications: This embodiment and the following modifications can be implemented in combination with each other to the extent that no technical contradiction occurs. Note that the above embodiment may be modified as follows.

[0084] The steel plates forming the rotor body 50 may be other than the adjustment steel plates 51 and the laminated steel plates 82. In short, as long as the balance adjustment portion 58 can be provided in the rotor 24, various types of laminated steel plates may be used by appropriately adjusting the radial dimension of the fluid circulation holes 60.

[0085] The number of fluid circulation holes 60 may be two, three, four, six or more. When the number of fluid circulation holes 60 is three or more, the number of circulation holes that overlap with the balance weight 33 in the axial direction may be changed appropriately to one, two, etc., and the number of circulation holes that are smaller in radial dimension than the circulation holes that overlap with the balance weight 33 may also be changed appropriately.

[0086] For example, if there are two fluid circulation holes 60, each fluid circulation hole 60 has a semicircular arc shape when viewed in the axial direction of the rotor body 50. In this case, the radial dimension of one fluid circulation hole 60 is smaller than the radial dimension of the other fluid circulation hole 60 that overlaps with the balance weight 33 in the axial direction to form the weight portion 52. The weight portions 52 may then be stacked in the axial direction to provide the balance adjustment portion 58.

[0087] In the first embodiment, the number of first fluid holes 61 formed from the first holes 511 and the number of second fluid holes 62 formed from the second holes 512 may be changed as appropriate depending on the size and weight of the balance weight 33. For example, there may be two first fluid holes 61 and one second fluid hole 62.

[0088] Similarly, in the second embodiment, the number of third fluid circulation holes 63 formed by the first circulation holes 511 and the second circulation holes 512 and the number of second fluid circulation holes 62 may be changed as appropriate depending on the size and weight of the balance weight 33. For example, there may be two third fluid circulation holes 63 and one second fluid circulation hole 62.

[0089] In the rotor 24, the radial dimension of the fluid communication holes 60 may be set to zero, and the balance adjustment portion 58 may be provided on the rotor 24. The first fluid circulation hole 61 may be formed with the first outer arcuate surface 61b positioned on the second imaginary circle C2. Even in this case, the weight portion 52 is formed at a position where the radial dimension of the first circulation hole 511 is smaller than the radial dimension of the second circulation hole 512 that overlaps with the balance weight 33 in the axial direction.

[0090] The fluid may be a gas other than a refrigerant, such as air, hydrogen, or nitrogen. [Explanation of symbols]

[0091] 10...Scroll-type electric compressor, 11...Housing, 15...Rotating shaft, 22...Motor, 23...Stator, 24...Rotor, 27...Fixed scroll, 28...Orbiting scroll, 33...Balance weight, 51...Adjusting steel plate as laminated steel plate, 52...Weight part, 58...Balance adjustment part, 60...Fluid flow hole, 82...Laminated steel plate, 511...First flow hole, 512...Second flow hole.

Claims

1. A rotation axis; a motor including a rotor fixed to the rotary shaft and a cylindrical stator surrounding the rotor; a compression unit that is driven by rotation of the rotary shaft and compresses a fluid; a housing that accommodates the motor and the compression unit, the compression section includes a fixed scroll provided in the housing and an orbiting scroll that revolves in association with rotation of the rotary shaft and forms a compression chamber that compresses the fluid between the orbiting scroll and the fixed scroll, the housing includes a motor housing that accommodates the motor, a compression unit housing that accommodates the compression unit, and a journal housing that rotatably supports the rotation shaft between the rotor and the orbiting scroll, a balance weight is provided on the rotary shaft, the balance weight extending in a radial direction of the rotary shaft and facing the rotor and the support housing in an axial direction of the rotary shaft; The rotor is formed by stacking a plurality of laminated steel plates in the axial direction, The rotor has a plurality of fluid passage holes formed in a circumferential direction of the rotor, the fluid passing through the fluid passage holes in the axial direction, In the scroll-type electric compressor, the fluid flow holes are formed by stacking flow holes formed in the laminated steel plates in the axial direction, the rotor has a balance adjustment portion provided at a position that offsets the centrifugal force generated by the balance weight, the laminated steel plate has a weight portion formed at a position where the radial dimension of the flow hole is smaller than the radial dimension of the flow hole that overlaps with the balance weight in the axial direction, and the balance adjustment portion is formed by stacking the weight portions in the axial direction.

2. the rotor is integrally provided with the rotary shaft by shrink fitting, 2. The scroll-type electric compressor according to claim 1, wherein the fluid circulation holes are elongated holes extending in an arc shape in the circumferential direction of the rotor, and inner circumferential surfaces of the fluid circulation holes extend along concentric circles centered on the axis of the rotating shaft, and the fluid circulation holes located radially inward of the balance adjustment portion are located radially inward of the fluid circulation holes that overlap with the balance weight in the axial direction.

3. 3. The scroll-type electric compressor according to claim 1, wherein the balance adjustment portion is provided by stacking the weight portions over the entire axial direction of the rotor.

4. 3. The scroll-type electric compressor according to claim 1, wherein the balance adjustment portion is provided by stacking the weight portion on a portion of the rotor in the axial direction.

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