JP2019173658A - Motor compressor - Google Patents

Abstract

To suppress noise while relieving machining accuracy and assembling accuracy.SOLUTION: A stator 14b is fixed to an inner housing 30. A bearing plate 51 holding a bearing 50 is fixed to the inner housing 30 with a first bolt 54. The inner housing 30 is stored in a motor housing 15. A discharge housing 16 is fixed to a compression part 13 with a second bolt 56. The compression part 13 is fixed to the inner housing 30. The motor housing 15 is fixed to the discharge housing 16 with a third bolt 57. An inner peripheral face 15c of the motor housing 15 and an outer peripheral face 30c of the inner housing 30 are separated from each other.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric compressor.

  A housing of the electric compressor houses a rotating shaft, a compression unit that compresses fluid by rotating the rotating shaft, and an electric motor that rotates the rotating shaft. The electric motor has a rotor that rotates integrally with the rotating shaft, and a cylindrical stator that surrounds the rotor and is fixed to the inner peripheral surface of the housing. The rotating shaft is rotatably supported by the housing via a bearing.

  In such an electric compressor, it is necessary to reduce the axial deviation between the axis of the rotating shaft and the axis of the bearing and the axial deviation between the axis of the rotating shaft and the axis of the stator as much as possible. Therefore, the processing accuracy of the bearing and the housing, the assembly accuracy of the bearing with respect to the housing, and the assembly accuracy of the stator with respect to the housing are required to be high accuracy.

  For example, in the electric compressor of Patent Document 1, a main frame that holds a bearing that supports one end of the rotating shaft, and a bearing that is disposed on the opposite side of the main frame from the electric motor and supports the other end of the rotating shaft. And a bottomed cylindrical centering member that houses the electric motor and the main frame and through which the rotation shaft passes. The subframe is fixed to the centering member, the electric motor is accommodated in the centering member, and the main frame is accommodated in the centering member. According to this, the processing accuracy of the bearing and the housing, the assembly accuracy of the bearing with respect to the housing, and the assembly accuracy of the stator with respect to the housing can be reduced.

JP 2010-163882 A

  However, in Patent Document 1, the centering member is fixed to the compression portion via a bolt while being accommodated in the housing, and further, the centering member is attached to the housing by welding or the like, for example. Since it is fixed, vibration from the compression portion is transmitted to the housing via the centering member, and noise is generated due to vibration of the housing.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an electric compressor capable of suppressing noise while reducing processing accuracy and assembly accuracy. .

  An electric compressor that solves the above problems includes a housing, a rotating shaft that is accommodated in the housing, a compression unit that compresses fluid by rotating the rotating shaft, and a rotor that rotates integrally with the rotating shaft. And an electric motor having a stator fixed to the housing and driving the compression unit, and a bearing that rotatably supports the rotating shaft with respect to the housing. Is an inner housing that houses the electric motor and to which the stator is fixed, a bearing plate that holds the bearing, an outer housing that houses the inner housing, and fluid compressed by the compression portion is discharged. And a discharge housing fixed to the compression part, and the compression part The outer housing is fixed to the discharge housing, the inner housing and the bearing plate are fixed by bolts, and the inner peripheral surface of the outer housing and the inner housing are fixed to the inner housing. The outer peripheral surface of the housing is separated.

  According to this, since the inner housing in which the stator is fixed and the bearing plate in which the bearing is held are separate members, when the bearing plate is fixed to the inner housing with bolts, the shaft center of the rotating shaft and the bearing Adjustments can be made to match the axis. Therefore, the processing accuracy of the bearing and the bearing plate, the assembly accuracy of the bearing with respect to the bearing plate, and the assembly accuracy of the stator with respect to the inner housing can be reduced.

  The inner peripheral surface of the outer housing fixed to the discharge housing is separated from the outer peripheral surface of the inner housing to which the compression portion is fixed. Therefore, compared with the case where the inner peripheral surface of the outer housing and the outer peripheral surface of the inner housing are in contact with each other, vibration from the compression portion is suppressed from being transmitted to the outer housing via the inner housing. It is possible to suppress the generation of noise due to vibration. From the above, noise can be suppressed while reducing processing accuracy and assembly accuracy.

  In the above electric compressor, the inner housing accommodates the electric motor and has a cylindrical main body member having an insertion opening for inserting the electric motor therein, and the inner housing is attached to the main body member and the insertion opening. A plate-like lid member that closes the portion, the compression portion is fixed to the main body member, the lid member is located on the opposite side of the compression portion, and the bearing plate It is good to be fixed to the lid member.

  According to this, the load from the compression part can be received by the main body member. Thus, for example, the lid member is positioned on the compression portion side and the compression portion is fixed to the lid member, and the load from the compression portion is more efficiently received by the inner housing than when the load from the compression portion is received by the lid member. Can receive well.

  According to the present invention, noise can be suppressed while reducing processing accuracy and assembly accuracy.

A side sectional view showing an electric compressor in an embodiment. The disassembled perspective view at the time of inserting a stator in an inner housing. The exploded perspective view at the time of fixing a compression part to an inner housing. The disassembled perspective view at the time of fixing a cover member to a main body member. The exploded perspective view at the time of fixing a bearing plate to an inner housing with the 1st bolt. The perspective view which shows the state by which the bearing plate was fixed to the inner housing with the 1st volt | bolt. The exploded perspective view at the time of fixing a discharge housing to a compression part with the 2nd bolt. The perspective view which shows the state by which the discharge housing was fixed to the compression part with the 2nd volt | bolt. The exploded perspective view at the time of fixing a motor housing to a discharge housing with a 3rd volt | bolt. The perspective view which shows the state by which the motor housing was fixed to the discharge housing with the 3rd volt | bolt. (A) is a sectional side view showing a part of an electric compressor in another embodiment, (b) is a sectional view schematically showing a stator core. The sectional side view which shows a part of electric compressor in another embodiment.

Hereinafter, an embodiment embodying an electric compressor will be described with reference to FIGS. In addition, the electric compressor of this embodiment is used for a vehicle air conditioner while being mounted on a vehicle.
As shown in FIG. 1, the electric compressor 10 includes a housing 11, a rotary shaft 12 accommodated in the housing 11, a compressor 13 that compresses a refrigerant that is a fluid by rotating the rotary shaft 12, and a compression And an electric motor 14 for driving the section 13.

  The housing 11 includes a bottomed cylindrical motor housing 15 and a bottomed cylindrical discharge housing 16 connected to the motor housing 15. The housing 11 has a cylindrical inner housing 30 that is accommodated in the motor housing 15. Therefore, the motor housing 15 is a cylindrical outer housing that houses the inner housing 30. The motor housing 15, the discharge housing 16, and the inner housing 30 are made of a metal material, for example, aluminum.

  The motor housing 15 has a plate-like bottom wall 15a and a peripheral wall 15b extending in a cylindrical shape from the outer peripheral portion of the bottom wall 15a. The discharge housing 16 has a plate-like bottom wall 16a and a peripheral wall 16b extending in a cylindrical shape from the outer peripheral portion of the bottom wall 16a. The opening edge 15e of the peripheral wall 15b of the motor housing 15 opposite to the bottom wall 15a and the opening edge 16e of the peripheral wall 16b of the discharge housing 16 opposite to the bottom wall 16a are abutted. The direction (axial direction) in which the axial center of the peripheral wall 15b of the motor housing 15 extends coincides with the direction (axial direction) in which the axial center of the peripheral wall 16b of the discharge housing 16 extends.

  A suction port (not shown) is formed in the motor housing 15. The suction port is connected to an external refrigerant circuit (not shown). A discharge port (not shown) is formed in the discharge housing 16. The discharge port is connected to an external refrigerant circuit.

  The rotating shaft 12 is accommodated in the motor housing 15. The direction (rotation axis direction) in which the rotation axis L <b> 1 of the rotation shaft 12 extends coincides with the axial direction of the peripheral wall 15 b of the motor housing 15 and the axial direction of the peripheral wall 16 b of the discharge housing 16. The compression unit 13 is accommodated near the discharge housing 16 in the motor housing 15 in the rotation axis direction of the rotation shaft 12.

  The compression unit 13 includes a fixed scroll 18 and a movable scroll 19 that is disposed to face the fixed scroll 18. The fixed scroll 18 is located closer to the discharge housing 16 than the movable scroll 19 in the rotational axis direction of the rotary shaft 12.

  The fixed scroll 18 includes a disk-shaped fixed side substrate 18 a and a fixed side spiral wall 18 b erected from the fixed side substrate 18 a toward the side opposite to the discharge housing 16. The movable scroll 19 has a movable substrate 19a having a disk shape, and a movable spiral wall 19b erected from the movable substrate 19a toward the fixed substrate 18a. The fixed-side spiral wall 18b and the movable-side spiral wall 19b are meshed with each other. The distal end surface of the fixed spiral wall 18b is in contact with the movable substrate 19a, and the distal surface of the movable spiral wall 19b is in contact with the fixed substrate 18a. The compression chamber 20 is partitioned by the fixed substrate 18a and the fixed spiral wall 18b, and the movable substrate 19a and the movable spiral wall 19b.

  A discharge chamber 16 c into which the refrigerant compressed in the compression chamber 20 is discharged is formed in the discharge housing 16. The discharge chamber 16c is defined by an inner surface of the discharge housing 16 and an end surface 18e on the fixed side substrate 18a opposite to the movable scroll 19e. A thin gasket 17 is interposed between the discharge housing 16 and the fixed substrate 18a. The gasket 17 prevents the refrigerant discharged to the discharge chamber 16c from leaking out of the discharge chamber 16c.

  An annular outer peripheral wall 18c is erected on the outer peripheral portion of the end surface of the fixed side substrate 18a on the movable scroll 19 side. The outer peripheral wall 18c surrounds the fixed-side spiral wall 18b. A cylindrical boss portion 19c projects from the end surface of the movable side substrate 19a opposite to the fixed scroll 18. The direction (axial direction) in which the axis of the boss portion 19 c extends coincides with the rotational axis direction of the rotary shaft 12.

  A bottomed cylindrical shaft support member 21 is accommodated on the side of the motor housing 15 opposite to the discharge housing 16 with respect to the compression portion 13. The shaft support member 21 is formed on the end surface on the discharge housing 16 side of the shaft support member 21 in the direction of the rotation axis of the rotary shaft 12, and on the bottom surface of the first recess 21a. It has a circular second recess 21b and a through hole 21c formed in the bottom surface of the second recess 21b.

  The movable side substrate 19a of the movable scroll 19 is located inside the first recess 21a. The boss portion 19c protrudes into the second recess 21b. The rotating shaft 12 passes through the through hole 21c. An annular slide bearing 22 is provided between the outer peripheral surface of the rotating shaft 12 and the inner peripheral surface of the through hole 21c. An end portion of the rotating shaft 12 on the compression portion 13 side is rotatably supported by the shaft support member 21 via a sliding bearing 22. The end surface on the discharge housing 16 side of the shaft support member 21 is in contact with the end surface of the outer peripheral wall 18 c of the fixed scroll 18. The outer diameter of the shaft support member 21 is the same as the outer diameter of the fixed side substrate 18a.

  An annular flange portion 12 a extending outward in the radial direction of the rotating shaft 12 protrudes from an end portion on the compression portion 13 side on the outer peripheral surface of the rotating shaft 12. The flange portion 12a is located inside the second recess 21b. The end surface of the flange portion 12a on the compression portion 13 side is located on the same plane as the end surface 12b of the rotation shaft 12 on the compression portion 13 side. Further, a part of the end surface 12b on the compression shaft 13 side of the rotary shaft 12 and a part of the flange portion 12a that spans a part of the end surface on the compression portion 13 side are movable from a position eccentric with respect to the rotation axis L1 of the rotation shaft 12. An eccentric shaft 12c protruding toward the scroll 19 is integrally formed. The axial direction of the eccentric shaft 12 c coincides with the rotational axis direction of the rotary shaft 12. The eccentric shaft 12c is inserted into the boss portion 19c.

  The movable scroll 19 is supported by the eccentric shaft 12c via an annular slide bearing 23 so as to be rotatable relative to the eccentric shaft 12c. In addition, a plurality of circular recesses 24 are formed on the outer peripheral portion of the end surface of the movable side substrate 19a opposite to the fixed scroll 18. The plurality of recesses 24 are arranged at predetermined intervals in the circumferential direction of the rotating shaft 12. An annular ring member 25 is fitted in each recess 24. Further, a pin 26 inserted into each ring member 25 protrudes from the bottom surface of the first recess 21 a of the shaft support member 21.

  The rotation of the rotary shaft 12 is transmitted to the movable scroll 19 via the eccentric shaft 12c and the sliding bearing 23, and the movable scroll 19 rotates. Then, when each pin 26 and the inner peripheral surface of each ring member 25 are in contact with each other, the rotation of the movable scroll 19 is prevented, and only the revolving motion of the movable scroll 19 is allowed. Thereby, the movable scroll 19 revolves while the movable spiral wall 19b contacts the fixed spiral wall 18b, and the volume of the compression chamber 20 decreases and the refrigerant is compressed.

  A bush 28 in which a balance weight 27 is integrated is fitted to the outer peripheral surface of the flange portion 12a. The balance weight 27 is integrally formed with the bush 28. The balance weight 27 is accommodated in the second recess 21b. The balance weight 27 cancels the centrifugal force acting on the movable scroll 19 when the movable scroll 19 revolves, thereby reducing the unbalance amount of the movable scroll 19.

  The inner housing 30 is accommodated on the opposite side of the discharge housing 16 from the shaft support member 21 in the motor housing 15. The inner housing 30 houses the electric motor 14. The electric motor 14 and the compression unit 13 are arranged side by side in the rotation axis direction of the rotation shaft 12. The electric motor 14 is disposed closer to the bottom wall 15 a of the motor housing 15 than the compression portion 13.

  The electric motor 14 includes a rotor 14a that rotates integrally with the rotary shaft 12, and a cylindrical stator 14b that surrounds the rotor 14a. The stator 14b has a cylindrical stator core 141b and a coil 142b wound around the stator core 141b. The electric motor 14 is driven by supplying electric power controlled by a drive circuit (not shown) to the coil 142b.

  The inner housing 30 includes a cylindrical main body member 31 and a plate-like lid member 41. The main body member 31 has an insertion opening 31a for housing the electric motor 14 and inserting the electric motor 14 therein. The lid member 41 is attached to the main body member 31 and closes the insertion opening 31a.

  As shown in FIG. 2, the main body member 31 of the inner housing 30 has an annular first ring portion 32 and second ring portion 33, and a plurality of connecting portions 34. The plurality of connecting portions 34 have a curved plate shape and connect the first ring portion 32 and the second ring portion 33. In the present embodiment, the main body member 31 has four connecting portions 34.

  The outer diameter of the first ring portion 32 and the outer diameter of the second ring portion 33 are the same. The outer diameters of the first ring portion 32 and the second ring portion 33 are the same as the outer diameter of the shaft support member 21 and the outer diameter of the fixed side substrate 18a. Further, the inner diameter of the first ring portion 32 and the inner diameter of the second ring portion 33 are the same.

  The four connecting portions 34 are arranged every 90 degrees in the circumferential direction of the first ring portion 32 and the second ring portion 33. The length of the main body member 31 in the four connecting portions 34 in the axial direction is the same. The length in the axial direction of the main body member 31 at the four connecting portions 34 is longer than the length in the axial direction of the stator core 141b.

  The inner peripheral surface 32a of the first ring portion 32 and the inner peripheral surfaces 34a of the four connecting portions 34 are continuous and located on the same surface. Further, the inner peripheral surface 33a of the second ring portion 33 and the inner peripheral surfaces 34a of the four connecting portions 34 are located on the same plane. A locking projection 34b protrudes from an end portion of the inner peripheral surface 34a of the four connecting portions 34 on the inner peripheral surface 33a side of the second ring portion 33. The end surface on the first ring portion 32 side of the locking projection 34 b is a flat surface extending in the radial direction of the first ring portion 32 and the second ring portion 33. The outer peripheral surface 34 c of each connecting portion 34 is located on the radially inner side of the first ring portion 32 and the second ring portion 33 with respect to the outer peripheral surface 32 c of the first ring portion 32 and the outer peripheral surface 33 c of the second ring portion 33. Yes. Therefore, the thickness of each connecting portion 34 is thinner than the thickness of the first ring portion 32 and the second ring portion 33.

  The stator 14b is fixed to the inner housing 30 by being fitted inside the main body member 31 of the inner housing 30 by shrink fitting. In the shrink fitting, the main body member 31 is first heated and expanded so that the inner diameter of the main body member 31, that is, the inner diameter of each of the first ring portion 32, the second ring portion 33, and the four connecting portions 34 is the outer diameter of the stator core 141b. Larger than. Thereafter, the stator 14b is inserted into the main body member 31 from the first ring portion 32 side. Therefore, the opening on the side opposite to the four connecting portions 34 in the first ring portion 32 forms an insertion opening 31 a of the main body member 31. The stator 14b is inserted into the main body member 31 until the end surface 141e of the stator core 141b located on the insertion direction side with respect to the main body member 31 comes into contact with each locking protrusion 34b. And the inner peripheral surface 34a of the four connection parts 34 is press-contacted with the outer peripheral surface of the stator core 141b by the shrinkage | contraction accompanying the transfer to the normal temperature of the main body member 31. Thereby, the stator 14 b is fixed to the inner housing 30.

  As shown in FIG. 3, a plurality of female screw holes 33 h are formed on the end surface 33 e of the second ring portion 33 on the side opposite to the connecting portion 34. In the present embodiment, the second ring portion 33 has four female screw holes 33h. A compression part bolt 35 for fixing the compression part 13 to the main body member 31 is screwed into each female screw hole 33h. As shown in FIG. 1, the fixed scroll 18 and the shaft support member 21 are formed with through holes 36 through which the respective compression portion bolts 35 are inserted. And each compression part volt | bolt 35 passes through each penetration hole 36, and is screwed in each internal thread hole 33h, Therefore In the state which the fixed scroll 18, ie, the compression part 13, pinched | supported the shaft support member 21 with the main body member 31. The body member 31 of the inner housing 30 is fixed.

  As shown in FIG. 4, a plurality of female screw holes 32 h are formed on the end surface 32 e of the first ring portion 32 opposite to the connecting portion 34. In the present embodiment, the first ring portion 32 has seven female screw holes 32h. An attachment bolt 42 for attaching the lid member 41 to the main body member 31 is screwed into each female screw hole 32h. On the outer peripheral portion of the lid member 41, through holes 43 through which the respective mounting bolts 42 are inserted are formed. Then, each attachment bolt 42 passes through each insertion hole 43 and is screwed into each female screw hole 32 h, whereby the lid member 41 is attached to the end surface 32 e of the first ring portion 32. Therefore, the lid member 41 is located on the opposite side of the main body member 31 from the compression portion 13.

  A circular insertion hole 44 is formed at the center of the lid member 41. The inner diameter of the insertion hole 44 is larger than the outer diameter of the rotating shaft 12. In a state where the lid member 41 is attached to the end surface 32 e of the first ring portion 32, the end surface of the rotating shaft 12 opposite to the compression portion 13 passes through the inside of the insertion hole 44 and protrudes from the lid member 41. In position.

  As shown in FIG. 1, the electric compressor 10 includes a bearing 50 that rotatably supports the end of the rotating shaft 12 on the side opposite to the compression portion 13 with respect to the housing 11. The bearing 50 is an annular slide bearing. The housing 11 has a bearing plate 51 that holds the bearing 50. The bearing plate 51 includes a cylindrical boss portion 52 and an annular flange portion 53 that protrudes radially outward of the boss portion 52 from the axial end portion of the boss portion 52 on the outer peripheral surface of the boss portion 52. is doing.

  The outer diameter of the boss portion 52 is smaller than the inner diameter of the insertion hole 44. Further, the inner diameter of the boss portion 52 is larger than the outer diameter of the rotating shaft 12. A bearing 50 is fitted on the inner peripheral surface of the boss portion 52. Therefore, the bearing 50 is held inside the boss portion 52. Further, the outer diameter of the flange portion 53 is larger than the inner diameter of the insertion hole 44.

  As shown in FIG. 5, a plurality of female screw holes 45 are formed around the insertion hole 44 in the lid member 41. In the present embodiment, the lid member 41 has three female screw holes 45. A first bolt 54 as a bolt for fixing the bearing plate 51 to the lid member 41 is screwed into each female screw hole 45. On the outer peripheral portion of the flange portion 53, through holes 55 through which the respective first bolts 54 are inserted are formed. Each first bolt 54 passes through each through hole 55 and is screwed into each female screw hole 45, whereby the bearing plate 51 is fixed to the lid member 41 of the inner housing 30.

  As shown in FIG. 6, in a state where the bearing plate 51 is fixed to the lid member 41 by the first bolts 54, the flange portion 53 is in surface contact with the end surface of the lid member 41 opposite to the main body member 31. Yes. Further, as shown in FIG. 1, the boss portion 52 passes through the insertion hole 44 and protrudes inside the main body member 31. The boss portion 52 surrounds the end of the rotating shaft 12 on the side opposite to the compression portion 13. An end portion of the rotating shaft 12 opposite to the compression portion 13 is rotatably supported by a bearing plate 51 via a bearing 50.

  As shown in FIG. 7, a plurality of female screw holes 18h are formed in the end surface 18e of the fixed side substrate 18a. In the present embodiment, the fixed side substrate 18a has eight female screw holes 18h. A second bolt 56 for fixing the discharge housing 16 to the compression portion 13 is screwed into each female screw hole 18h. The bottom wall 16a of the discharge housing 16 is formed with a through hole 16h through which each second bolt 56 is inserted. And each discharge bolt 16 is being fixed to the stationary side board | substrate 18a, ie, the compression part 13, when each 2nd volt | bolt 56 passes through each penetration hole 16h and is screwed in each internal thread hole 18h.

  As shown in FIG. 8, in a state where the discharge housing 16 is fixed to the fixed side substrate 18 a by the respective second bolts 56, the outer peripheral portion of the bottom wall 16 a and the peripheral wall 16 b of the discharge housing 16 are the outer periphery of the first ring portion 32. The surface 32c, the outer peripheral surface 33c of the second ring portion 33, the outer peripheral surface of the shaft support member 21, and the outer peripheral surface of the fixed side substrate 18a are located on the radially outer side of the rotary shaft 12.

  As shown in FIG. 9, a plurality of female screw holes 15 h are formed in the opening edge 15 e of the motor housing 15. In the present embodiment, the motor housing 15 has eight female screw holes 15h. A third bolt 57 for fixing the motor housing 15 to the discharge housing 16 is screwed into each female screw hole 15h. The discharge housing 16 is formed with through holes 16k that penetrate the outer peripheral portion of the bottom wall 16a and the peripheral wall 16b and through which the third bolts 57 are inserted. Each third bolt 57 passes through each through hole 16k and is screwed into each female screw hole 15h, whereby the motor housing 15 is fixed to the discharge housing 16.

  As shown in FIG. 10, the motor housing 15 is fixed to the discharge housing 16 by the respective third bolts 57, whereby the assembly of the electric compressor 10 of the present embodiment is completed. As shown in FIG. 1, the inner peripheral surface 15 c of the peripheral wall 15 b of the motor housing 15 and the outer peripheral surface 30 c of the inner housing 30 are separated from each other. In the present embodiment, the outer peripheral surface 30 c of the inner housing 30 is formed by the outer peripheral surface 32 c of the first ring portion 32, the outer peripheral surface 33 c of the second ring portion 33, and the outer peripheral surface 34 c of each connecting portion 34. The outer peripheral surface 32 c of the first ring portion 32 and the outer peripheral surface 33 c of the second ring portion 33 are separated from the inner peripheral surface 15 c of the peripheral wall 15 b of the motor housing 15.

Next, the operation of this embodiment will be described.
The inner housing 30 to which the stator 14b is fixed and the bearing plate 51 that holds the bearing 50 are separate members. When the bearing plate 51 is fixed to the inner housing 30 by the first bolts 54, the clearances between the first bolts 54 and the inner peripheral surfaces of the through holes 55 of the bearing plate 51, and the inner housing 30. The position of the bearing plate 51 can be adjusted. Therefore, when the bearing plate 51 is fixed to the inner housing 30 by the first bolts 54, the bearing plate 51 is adjusted so that the axis of the rotary shaft 12 and the axis of the bearing 50 coincide with each other. Fix to 30. Thereby, the axial shift of the shaft center of the rotating shaft 12 and the shaft center of the bearing 50 is suppressed, and the rotation of the rotating shaft 12 becomes smooth.

  Further, the inner peripheral surface 15c of the peripheral wall 15b of the motor housing 15 fixed to the discharge housing 16 by the respective third bolts 57 is separated from the outer peripheral surface 30c of the inner housing 30 to which the compression portion 13 is fixed. Therefore, compared with the case where the inner peripheral surface 15 c of the peripheral wall 15 b of the motor housing 15 and the outer peripheral surface 30 c of the inner housing 30 are in contact, vibration from the compression portion 13 is transmitted to the motor housing 15 via the inner housing 30. The occurrence of noise due to vibration of the motor housing 15 is suppressed.

In the above embodiment, the following effects can be obtained.
(1) When the bearing plate 51 is fixed to the inner housing 30 by the first bolts 54, the shaft center of the rotary shaft 12 and the shaft center of the bearing 50 can be adjusted to coincide with each other. Therefore, the processing accuracy of the bearing 50 and the bearing plate 51, the assembly accuracy of the bearing 50 with respect to the bearing plate 51, and the assembly accuracy of the stator 14b with respect to the inner housing 30 can be reduced. The inner peripheral surface 15 c of the peripheral wall 15 b of the motor housing 15 is separated from the outer peripheral surface 30 c of the inner housing 30. Therefore, compared with the case where the inner peripheral surface 15 c of the peripheral wall 15 b of the motor housing 15 and the outer peripheral surface 30 c of the inner housing 30 are in contact, vibration from the compression portion 13 is transmitted to the motor housing 15 via the inner housing 30. The occurrence of noise due to vibration of the motor housing 15 can be suppressed. From the above, noise can be suppressed while reducing processing accuracy and assembly accuracy.

  (2) The compression unit 13 is fixed to the main body member 31. The lid member 41 is located on the side opposite to the compression unit 13, and the bearing plate 51 is fixed to the lid member 41. According to this, the load from the compression part 13 can be received by the main body member 31. Therefore, for example, compared with the case where the lid member 41 is positioned on the compression unit 13 side and the compression unit 13 is fixed to the lid member 41, and the load from the compression unit 13 is received by the lid member 41, the compression unit 13 Can be efficiently received by the inner housing 30.

  (3) For example, the shape of the inner peripheral surface 15 c of the peripheral wall 15 b of the motor housing 15 can be simplified as compared with the case where the stator 14 b is shrink-fitted to the inner peripheral surface 15 c of the peripheral wall 15 b of the motor housing 15. Further, since the stress concentration due to the complicated shape of the inner peripheral surface 15c of the peripheral wall 15b of the motor housing 15 is alleviated, it is not necessary to increase the thickness of the peripheral wall 15b of the motor housing 15, and the motor housing 15 is lightweight. Can be

  (4) Since it is not necessary to project a cylindrical boss portion for holding the bearing 50 on the inner surface of the bottom wall 15a of the motor housing 15, the structure of the motor housing 15 can be simplified.

  (5) When the stator 14b is shrink-fitted on the inner peripheral surface 15c of the peripheral wall 15b of the motor housing 15, the deformation of the inner peripheral surface 15c of the peripheral wall 15b of the motor housing 15 due to the pressure in the motor housing 15 is taken into consideration. Therefore, it is necessary to set a large allowance for shrink-fitting of the inner peripheral surface 15c of the peripheral wall 15b of the motor housing 15 with respect to the motor housing 15. However, since the pressure in the motor housing 15 acts on both the inner peripheral surface 34 a of each connecting portion 34 and the outer peripheral surface 34 c of each connecting portion 34 at each connecting portion 34 of the inner housing 30. The pressure acting on each of the connecting portions 34 is offset, and the connecting portions 34 are not easily deformed by the pressure in the motor housing 15. Therefore, the allowance for shrink fitting of the inner peripheral surface 34a of each connecting portion 34 with respect to the stator 14b can be set small.

In addition, you may change the said embodiment as follows.
○ As shown in FIGS. 11A and 11B, the stator 14b is not fixed to the inner housing 30 by being fitted inside the body member 31 of the inner housing 30 by shrink fitting. May be fixed to the inner housing 30 by bolts 58.

  As shown in FIG. 11B, the stator core 141b has a plurality (for example, four) of protruding portions 141c that protrude from the outer peripheral surface of the stator core 141b to the radially outer side of the stator core 141b. As shown in FIG. 11A, each overhanging portion 141c extends in the axial direction of the stator core 141b. A plurality of female screw holes 21 h are formed on the end surface of the shaft support member 21 on the inner housing 30 side. Bolts 58 are screwed into the respective female screw holes 21h. Each overhanging portion 141c is formed with a through hole 141h through which each bolt 58 is inserted. In addition, the first ring portion 32 of the main body member 31 is formed with a communication hole 32k that communicates with the through hole 141h of each overhanging portion 141c. Further, the second ring portion 33 of the main body member 31 is formed with communication holes 33k communicating with the through holes 141h of the overhang portions 141c and the female screw holes 21h, respectively. Further, the cover member 41 is formed with a communication hole 41 k that communicates with each communication hole 32 k of the first ring portion 32.

  The bolts 58 pass through the communication holes 41k of the lid member 41, the communication holes 32k of the first ring portion 32, the through holes 141h of the overhang portions 141c, and the communication holes 33k of the second ring portion 33. Then, it is screwed into each female screw hole 21h. Thereby, the inner housing 30 is fixed to the shaft support member 21, and the stator 14 b is fixed to the inner housing 30. The shaft support member 21 and the fixed scroll 18 are fixed to each other by a bolt (not shown). Therefore, the fixed scroll 18, that is, the compression portion 13 is fixed to the main body member 31 of the inner housing 30 with the bolts 58 sandwiching the shaft support member 21 together with the main body member 31.

  As shown in FIG. 12, the bearing plate 51 may be fixed to the lid member 41 of the inner housing 30 by using the bolts 58 described in the embodiment shown in FIGS. 11 (a) and 11 (b). . The flange portion 53 of the bearing plate 51 is formed with a communication hole 53k that communicates with each communication hole 41k of the lid member 41. The bolts 58 are respectively connected to the communication holes 53k of the flange portion 53, the communication holes 41k of the lid member 41, the communication holes 32k of the first ring portion 32, the through holes 141h of the overhang portions 141c, and the second ring. It passes through each communication hole 33k of the portion 33 and is screwed into each female screw hole 21h. Thereby, the bearing plate 51 is fixed to the lid member 41 of the inner housing 30. In this case, each bolt 58 that functions to fix the stator 14b to the inner housing 30 also functions as a first bolt for fixing the bearing plate 51 to the lid member 41, so the number of parts can be reduced. it can.

  In the embodiment, the lid member 41 may be positioned on the compression unit 13 side and the compression unit 13 may be fixed to the lid member 41. In this case, the main body member 31 has a bottom portion that closes the opening portions of the first ring portion 32 opposite to the four connecting portions 34. The stator 14b is inserted into the main body member 31 from the second ring portion 33 side. Therefore, the opening on the side opposite to the four connecting portions 34 in the second ring portion 33 forms an insertion opening for the main body member 31. The lid member 41 closes a part of the opening on the side opposite to the four connecting portions 34 in the second ring portion 33. In this case, the lid member 41 may not be plate-shaped, and may be, for example, an annular shape whose inner diameter is smaller than the inner diameter of the second ring portion 33. The bearing plate 51 is fixed to the bottom of the main body member 31 by each first bolt 54.

  In the embodiment, the compression unit 13 is fixed to the main body member 31 of the inner housing 30 in a state where the shaft support member 21 is sandwiched with the main body member 31 by the respective compression unit bolts 35, but is not limited thereto. For example, the shaft support member 21 in a state where the compression portion 13 is fixed is press-fitted inside the main body member 31, so that the compression portion 13 is fixed to the main body member 31 of the inner housing 30 via the shaft support member 21. May be.

In the embodiment, the fixing method between the discharge housing 16 and the compression unit 13 is not limited to a fixing method using a bolt, and may be changed as appropriate.
In the embodiment, the fixing method of the motor housing 15 and the discharge housing 16 is not limited to the fixing method using bolts, and may be changed as appropriate.

In the embodiment, the numbers of the first bolts 54, the second bolts 56, and the third bolts 57 are not particularly limited.
In the embodiment, the bearing 50 may be a rolling bearing, for example.

  In embodiment, the compression part 13 is not restricted to the type comprised by the fixed scroll 18 and the movable scroll 19, For example, you may change into a piston type, a vane type, etc.

  (Circle) in embodiment, the electric compressor 10 may not be used for a vehicle air conditioner, and may be used for another air conditioner.

  DESCRIPTION OF SYMBOLS 10 ... Electric compressor, 11 ... Housing, 12 ... Rotary shaft, 13 ... Compression part, 14 ... Electric motor, 14a ... Rotor, 14b ... Stator, 15 ... Motor housing which is an outer housing, 15c ... Inner peripheral surface, 16 ... Discharge housing, 30 ... inner housing, 30c ... outer peripheral surface, 31 ... main body member, 31a ... insertion opening, 41 ... lid member, 50 ... bearing, 51 ... bearing plate, 54 ... first bolt as a bolt.

Claims (2)

A housing;
A rotating shaft housed in the housing;
A compression unit that compresses fluid by rotating the rotation shaft;
An electric motor that has a rotor that rotates integrally with the rotating shaft, and a stator that is fixed to the housing, and that drives the compression unit;
An electric compressor comprising: a bearing that rotatably supports the rotating shaft with respect to the housing;
The housing is
An inner housing that houses the electric motor and to which the stator is fixed;
A bearing plate for holding the bearing;
An outer housing that houses the inner housing;
A fluid housing compressed by the compression unit and discharged to the compression unit;
The compression part is fixed to the inner housing,
The outer housing is fixed to the discharge housing;
The inner housing and the bearing plate are fixed by bolts,
An electric compressor, wherein an inner peripheral surface of the outer housing and an outer peripheral surface of the inner housing are separated from each other. The inner housing is
A cylindrical main body member that houses the electric motor and has an insertion opening for inserting the electric motor therein;
A plate-like lid member that is attached to the main body member and closes the insertion opening,
The compression part is fixed to the body member;
The lid member is located on the opposite side of the compression section;
The electric compressor according to claim 1, wherein the bearing plate is fixed to the lid member.