JP2017008949A - Electric compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the cooling performance of an electric motor.SOLUTION: In a rotor core 24a, refrigerant passages 70 are formed, which penetrate in the axial direction of a rotating shaft 23 to provide communication between a first region Z1 and a second region Z2. At the end of the rotor core 24a on the first region Z1 side, a first end plate 81 is provided, which is formed with a first communication opening 81h for bringing the first region Z1 and the refrigerant passages 70 in communication with each other via first openings 701 of the refrigerant passages 70. Radially outer areas of the first openings 701 based on the rotating shaft 23 are covered with the first end plate 81. At the end of the rotor core 24a on the second region Z2 side, a second end plate 82 is provided, which is formed with a second communication opening 82h for bringing the second region Z2 and the refrigerant passages 70 in communication with each other via second openings 702 of the refrigerant passages 70. Radially outer areas of the second openings 702 based on the rotating shaft 23 are covered with the second end plate 82, and radially inner areas of the second openings 702 based on the rotating shaft 23 are not covered with the second end plate 82.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an electric compressor.

  Generally, a housing of an electric compressor is formed of a bottomed cylindrical motor housing and a bottomed cylindrical discharge housing joined to an opening end of the motor housing. An inverter cover is attached to the motor housing. A rotating shaft is accommodated in the motor housing. Further, the motor housing accommodates a compression part having a compression chamber for compressing the refrigerant and an electric motor for driving the compression part. Furthermore, a motor drive circuit for driving the electric motor is accommodated in the space defined by the motor housing and the inverter cover.

  The electric motor includes a rotor (rotor) that rotates integrally with a rotating shaft, and a stator (stator) that is fixed to the inner peripheral surface of the motor housing so as to surround the rotor. The stator is configured such that a coil is disposed in a slot between a plurality of teeth formed on an annular stator core fixed to an inner peripheral surface of a motor housing. The rotor is composed of a rotor core fixed to the rotating shaft and a plurality of permanent magnets embedded in the rotor core.

  A suction port is formed in the motor housing. An external refrigerant circuit is connected to the suction port. In addition, a discharge chamber is defined between the motor housing and the discharge housing, a discharge port is formed in the discharge housing, and an external refrigerant circuit is connected to the discharge port. Then, the refrigerant sucked into the motor housing from the suction port flows toward the compression portion through a passage formed between the outer peripheral surface of the stator core and the inner peripheral surface of the motor housing, and is sucked into the compression chamber. . The refrigerant sucked into the compression chamber is compressed in the compression chamber and discharged into the discharge chamber, flows out to the external refrigerant circuit through the discharge port, and is returned to the motor housing through the suction port.

  Here, although the stator core is cooled by the refrigerant flowing through the passage formed between the outer peripheral surface of the stator core and the inner peripheral surface of the motor housing, the rotor core is hardly cooled by the refrigerant and the entire electric motor is difficult to cool.

  For this reason, for example, Patent Document 1 discloses a structure in which a plurality of cooling holes (refrigerant passages) penetrating in the axial direction are formed in the rotor core, and the refrigerant sucked into the motor housing from the suction port is allowed to flow into the cooling holes. Is disclosed. According to this, the rotor core can be cooled by the refrigerant flowing through each cooling hole, and the cooling performance of the entire electric motor is improved.

Korean Published Patent No. 2011-128680

However, there is a desire to further improve the cooling performance of the electric motor than Patent Document 1.
The present invention has been made to solve the above problems, and an object thereof is to provide an electric compressor capable of improving the cooling performance of an electric motor.

  In order to achieve the above object, the invention according to claim 1 is an electric motor comprising a rotor that rotates integrally with a rotating shaft, a stator that surrounds the rotor and is fixed to an inner peripheral surface of a housing, and the rotating shaft. An electric motor comprising a compression section that is driven by rotation of the motor and a motor drive circuit that drives the electric motor, and a coil is disposed in a slot between a plurality of teeth formed in a stator core that constitutes the electric motor. In the compressor, a first region where the first coil end on the compression part side of the coil is located and a second coil end on the coil opposite to the compression part side are located in the housing. A suction port that is open to the second region and is connected to an external refrigerant circuit. The rotor core that constitutes the rotor is formed with a refrigerant passage that penetrates in the axial direction of the rotating shaft and communicates the first region and the second region, and is arranged on the first region side of the rotor core. The end portion is provided with a first end plate formed with a first communication port that communicates the first region and the refrigerant passage through the first opening of the refrigerant passage. The outer region in the radial direction with respect to the rotation axis is covered with the first end plate, and the second region and the refrigerant passage are provided at the end of the rotor core on the second region side. A second end plate having a second communication port that communicates with the refrigerant passage through the second opening is provided, and a radially outer region of the second opening with respect to the rotation axis is defined by the second end plate. Covered with two end plates and radially inward with respect to the rotation axis of the second opening It is summarized in that which is not covered by the second end plate.

  According to this invention, the second coil end is cooled by the refrigerant sucked into the second region via the suction port. Subsequently, the refrigerant in the second region flows into the refrigerant passage, and the rotor core is cooled by the refrigerant flowing through the refrigerant passage. Further, the refrigerant flowing through the refrigerant passage is centrifuged into a gas-phase refrigerant and oil by the rotation of the rotor, and the oil is radially outwardly based on the rotation axis in the refrigerant passage by the centrifugal force due to the rotation of the rotor. Blown away. The rotor core is efficiently cooled by the oil blown to the radially outer region with respect to the rotation axis in the refrigerant passage by the centrifugal force generated by the rotation of the rotor. Furthermore, the oil flowing through the refrigerant passage is dammed to the first end plate at the first opening of the refrigerant passage and temporarily stored in a radially outer region based on the rotation axis of the first opening in the refrigerant passage, The rotor core is further efficiently cooled by the temporarily stored oil. In addition, the refrigerant flowing through the refrigerant passage flows out to the first region through the first opening and the first communication port. Then, the first coil end is cooled by the refrigerant that has flowed into the first region. Thus, the stator core can be cooled by cooling the first coil end and the second coil end. As a result, the cooling performance of the electric motor can be improved.

  Further, the oil blown to the radially outer region with the rotation axis as a reference by the centrifugal force due to the rotation of the rotor on the second region side in the refrigerant passage is blown away by the refrigerant flowing from the second region into the refrigerant passage. This can be prevented by the second end plate. Therefore, the oil blown off in the radially outer region with respect to the rotation axis by the centrifugal force due to the rotation of the rotor on the second region side in the refrigerant passage is easily stored in the refrigerant passage, and the rotor core is cooled by the oil. The cooling performance of the electric motor can be further improved.

  The invention according to claim 2 is characterized in that, in the invention according to claim 1, a collision wall is provided in the refrigerant passage and in a radially inner region with reference to the rotation axis of the refrigerant passage. The gist.

  According to this invention, the oil that could not be completely separated from the refrigerant by the rotation of the rotor can be separated from the refrigerant by colliding the refrigerant flowing through the refrigerant passage with the collision wall. Therefore, the rotor core can be further easily cooled by the oil, and the cooling performance of the electric motor can be further improved.

  The invention according to claim 3 is the invention according to claim 2, wherein the rotary shaft is supported by a bearing, the bearing is held by a bearing holding portion provided in the housing, and the collision wall is formed by the bearing. The gist is the end wall of the holding portion.

  According to this invention, since the bearing holding part is an existing configuration of the electric compressor, it is not necessary to separately provide a member that functions as a collision wall, and the configuration can be simplified. Further, since the end wall of the bearing holding portion is provided in the refrigerant passage, the physique along the axial direction of the electric compressor is compared with the case where the end wall of the bearing holding portion is provided outside the refrigerant passage. It can be downsized.

The gist of a fourth aspect of the present invention is that, in the third aspect of the invention, the bearing holding portion and the rotating shaft communicate with the refrigerant passage.
According to the present invention, since the oil flowing through the refrigerant passage flows between the bearing holding portion and the rotating shaft, the bearing can be lubricated and cooled by the oil flowing between the bearing holding portion and the rotating shaft.

The gist of the invention according to claim 5 is that, in the invention according to any one of claims 1 to 4, a plurality of the refrigerant passages are formed in a circumferential direction of the rotating shaft.
According to the present invention, for example, the cooling performance of the electric motor can be improved as compared with the case where there is only one refrigerant passage.

  A sixth aspect of the present invention is the invention according to any one of the first to fifth aspects, wherein the outer side in the radial direction is in the refrigerant passage and is based on the rotation axis of the refrigerant passage. The gist of the present invention is that the region has a protruding wall extending in the axial direction in the refrigerant passage.

  According to the present invention, the oil blown off in the radially outer region with respect to the rotation axis by the centrifugal force due to the rotation of the rotor can be stored in the regions on both sides of the ridge wall in the refrigerant passage. Therefore, the oil blown off in the radially outer region with respect to the rotation axis due to the centrifugal force due to the rotation of the rotor can be prevented from staying locally in the refrigerant passage, and the oil makes the rotor core efficient. It can cool well.

  The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein the compression section, the electric motor, and the motor drive circuit are arranged in the axial direction of the rotating shaft in this order. The gist is that they are arranged side by side.

  According to this invention, the motor drive circuit can be cooled by the refrigerant sucked into the second region through the suction port.

  According to this invention, the cooling performance of the electric motor can be improved.

A side sectional view showing an electric compressor in an embodiment. FIG. 1 is a sectional view taken along line 1-1 in FIG. FIG. 2 is a sectional view taken along line 2-2 in FIG. 1.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.
As shown in FIG. 1, the housing 11 of the electric compressor 10 includes a motor housing 12 having a bottomed cylindrical shape made of a metal material (made of aluminum in this embodiment), and an open end (the left end in FIG. 1) of the motor housing 12. ) And a discharge housing 13 having a bottomed cylindrical shape made of a metal material (made of aluminum in the present embodiment). A discharge chamber 15 is defined between the motor housing 12 and the discharge housing 13. An inverter cover 41 having a bottomed cylindrical shape made of a metal material (made of aluminum in this embodiment) is joined to the bottom wall 12 a of the motor housing 12.

  A rotating shaft 23 is accommodated in the motor housing 12. In the motor housing 12, a compression unit 18 for compressing the refrigerant and an electric motor 19 for driving the compression unit 18 are arranged side by side along the direction (axial direction) in which the axis L of the rotary shaft 23 extends (horizontal direction). Next to each other). The electric motor 19 is disposed closer to the bottom wall 12 a (right side in FIG. 1) of the motor housing 12 than the compression portion 18. A housing space 41a is defined by the bottom wall 12a of the motor housing 12 and the inverter cover 41, and a motor drive circuit 40 (in FIG. 1, indicated by a two-dot chain line) for driving the electric motor 19 is defined in the housing space 41a. Is shown). The motor drive circuit 40 is attached in close contact with the outer surface of the bottom wall 12a, and is thermally coupled to the bottom wall 12a. Therefore, in this embodiment, the compression part 18, the electric motor 19, and the motor drive circuit 40 are arrange | positioned along with the axial direction of the rotating shaft 23 in this order.

  The compression unit 18 includes a fixed scroll 20 fixed in the motor housing 12 and a movable scroll 21 disposed to face the fixed scroll 20. A compression chamber 22 whose volume can be changed is defined between the fixed scroll 20 and the movable scroll 21. In the motor housing 12, a cylindrical shaft support member 30 that supports one end of the rotary shaft 23 is disposed between the electric motor 19 and the compression portion 18. A bearing holding portion 30 a is provided on the inner peripheral side of the shaft support member 30. The bearing holding portion 30a holds a sliding bearing 23a as a bearing that rotatably supports one end side of the rotary shaft 23. Further, a shaft support 121a is formed on the bottom wall 12a. The shaft support 121a holds a sliding bearing 23b that rotatably supports the other end of the rotary shaft 23. The rotating shaft 23 is rotatably supported with respect to the shaft support member 30 and the bottom wall 12a of the motor housing 12 via sliding bearings 23a and 23b.

  A suction port 30 h is formed in the outer peripheral portion of the shaft support member 30. The outer side of the outer peripheral portion of the movable scroll 21 communicates with the suction port 30h, and the motor housing 12 communicates with the compression chamber 22 via the suction port 30h.

  A stator 25 (stator) is fixed to the inner peripheral surface of the motor housing 12, and the stator 25 is formed with a plurality of teeth 27 (see FIG. 5) formed on an annular stator core 26 fixed to the inner peripheral surface of the motor housing 12. 2 and FIG. 3), a coil 29 is disposed in a slot 27s. The stator core 26 is configured by laminating a plurality of core plates 26c that are magnetic bodies (electromagnetic steel plates). A rotor 24 (rotor) is provided inside the stator 25. The rotor 24 includes a rotor core 24a fixed to the rotary shaft 23 and a plurality of permanent magnets 24b embedded in the rotor core 24a. The rotor core 24a is configured by laminating a plurality of core plates 24c that are magnetic bodies (electromagnetic steel plates).

  As shown in FIGS. 2 and 3, a passage forming portion 12 c that protrudes radially outward of the rotating shaft 23 is formed in a part of the portion located above the motor housing 12. The passage forming portion 12 c extends linearly along the axial direction of the rotating shaft 23. Between the passage forming portion 12c and the stator core 26, a cluster block 50 having a rectangular box shape made of synthetic resin is disposed. In the cluster block 50, connection terminals 50a are arranged. The outer bottom surface 50 c of the cluster block 50 has an arc shape along the outer peripheral surface of the stator core 26, and extends parallel to the axial direction of the stator core 26.

  As shown in FIG. 1, a gap filling member 51 made of a resin material is provided between the passage forming portion 12 c and the cluster block 50. Then, by this gap filling member 51, in the motor housing 12, the first region Z <b> 1 in which the first coil end 291 on the compression portion 18 side in the coil 29 is positioned and the first region Z <b> 1 in the coil 29 on the opposite side to the compression portion 18 side. Communication between the passage forming portion 12c and the cluster block 50 with the second region Z2 where the two coil ends 292 are located is blocked.

  From the first coil end 291, leading ends of U-phase, V-phase, and W-phase lead wires 29 a (only one is shown in FIG. 1) are drawn out. The starting end of each lead wire 29 a is electrically connected to the connection terminal 50 a through the first insertion hole 501 of the cluster block 50.

  A through hole 12 b is formed in the bottom wall 12 a of the motor housing 12. A sealing terminal 42 is disposed in the through hole 12b. Each of the sealing terminals 42 includes three metal terminals 43 electrically connected to the motor drive circuit 40 and three glass insulating members 44 that fix the metal terminals 43 while being insulated from the bottom wall 12a (see FIG. 1 only one is shown). One end of the metal terminal 43 is electrically connected to the motor drive circuit 40 via the cable 45. The other end of the metal terminal 43 is electrically connected to the connection terminal 50 a through the second insertion hole 502 of the cluster block 50.

  A suction port 12 h is formed in the motor housing 12. The suction port 12h is entirely open in the second region Z2 in the motor housing 12. An external refrigerant circuit 60 is connected to the suction port 12h. A discharge port 16 is formed on one end wall (left end in FIG. 1) of the discharge housing 13, and an external refrigerant circuit 60 is connected to the discharge port 16.

  As shown in FIGS. 2 and 3, the rotor core 24a has a plurality of refrigerant passages 70 (6 in the present embodiment) that penetrate the axial direction of the rotary shaft 23 and communicate the first region Z1 and the second region Z2. ) Is formed. Each refrigerant passage 70 is formed at intervals in the circumferential direction of the rotating shaft 23. A ridge wall 70 b extending in the axial direction in the refrigerant passage 70 is formed in each refrigerant passage 70 and in a radially outer region with respect to the rotation shaft 23 of the refrigerant passage 70. In the radial direction of the rotating shaft 23, the outermost portions 70 e in both sides of the refrigerant passage 70 sandwiching the ridge wall 70 b correspond to the outermost portions of the respective refrigerant passages 70.

  The refrigerant passage 70 is formed by punching each core plate 24c. As shown in FIG. 3, an annular notch 70 k is formed on the refrigerant passage 70 on the first region Z <b> 1 side so that the refrigerant passages 70 adjacent to each other in the circumferential direction of the rotating shaft 23 communicate with each other. The cutout portion 70k is formed by cutting out the inner peripheral surface of the plurality of core plates 24c stacked on the first region Z1 side of the plurality of core plates 24c. The inner peripheral surface of the cutout portion 70k is located on the radially outer side than the radially inner surface of the rotation shaft 23 in the refrigerant passage 70.

  A disc-shaped first end plate 81 is attached to the end of the rotor core 24a on the first region Z1 side. The first end plate 81 is formed with a circular first communication port 81 h that allows the first region Z1 and each refrigerant passage 70 to communicate with each other through the first opening 701 of each refrigerant passage 70. The inner diameter of the first communication port 81h is smaller than the inner diameter of the imaginary circle R1 that passes through the outermost part 70e in the regions on both sides of the rib wall 70b in the refrigerant passage 70. Therefore, the periphery of the first communication port 81h in the first end plate 81 protrudes inward in the radial direction of the rotation shaft 23 from the virtual circle R1, and a radially outer region with respect to the rotation shaft 23 of the first opening 701 is defined. Covering. In the present embodiment, the inner diameter of the first communication port 81h is set so that the inner peripheral surface of the first communication port 81h is positioned on the radially inner side of the rotation shaft 23 with respect to the ridge wall 70b. In addition, the inner diameter of the first communication port 81 h is larger than the outer diameter of the bearing holding portion 30 a of the shaft support member 30.

  As shown in FIG. 2, a disc-shaped second end plate 82 is attached to the end of the rotor core 24a on the second region Z2 side. The second end plate 82 is formed with a circular second communication port 82h that allows the second region Z2 and each refrigerant passage 70 to communicate with each other through the second opening 702 of each refrigerant passage 70. The inner diameter of the second communication port 82h is smaller than the inner diameter of the virtual circle R1 that passes through the outermost part 70e in the regions on both sides of the ridge wall 70b in the refrigerant passage 70. Therefore, the second communication port 82 h and the second end plate 82 around the second communication port 82 h protrude radially inward of the rotation shaft 23 from the virtual circle R 1, and a radially outer region of the second opening 702 with respect to the rotation shaft 23 as a reference. Covering. In the present embodiment, the inner diameter of the second communication port 82h is set so that the inner peripheral surface of the second communication port 82h is located on the radially inner side of the rotation shaft 23 with respect to the protruding wall 70b. In addition, the first end plate 81 and the second end plate 82 prevent the permanent magnet 24b from jumping out in the axial direction of the rotary shaft 23.

  As shown in FIG. 3, a part of the bearing holding portion 30 a of the shaft support member 30 is inserted inside the notch portion 70 k through the first communication port 81 h of the first end plate 81. The outer peripheral surface of the bearing holding portion 30 a is located on the radially outer side than the radially inner surface of the rotation shaft 23 in the refrigerant passage 70. As a result, the outer peripheral portion of the bearing holding portion 30a is in each refrigerant passage 70 and in the radially inner region with respect to the rotation shaft 23 of each refrigerant passage 70 from the first region Z1 side to each refrigerant passage 70. Has been inserted inside. In addition, the end wall 30e of the bearing holding portion 30a is provided in each refrigerant passage 70 and in a radially inner region with respect to the rotation shaft 23 of each refrigerant passage 70 as a reference. As shown in FIG. 1, the bearing holding portion 30 a and the rotary shaft 23 communicate with each refrigerant passage 70.

Next, the operation of this embodiment will be described.
In the electric compressor 10, the electric power controlled by the motor drive circuit 40 is supplied to the electric motor 19, whereby the rotary shaft 23 rotates together with the rotor 24 at the controlled rotational speed. Then, in the compression unit 18, the volume of the compression chamber 22 between the fixed scroll 20 and the movable scroll 21 is reduced. Then, the refrigerant is sucked into the motor housing 12 from the external refrigerant circuit 60 through the suction port 12h.

  Here, the communication between the first region Z1 and the second region Z2 through the passage forming portion 12c and the cluster block 50 is blocked by the gap filling member 51. Therefore, the refrigerant sucked into the motor housing 12 through the suction port 12h flows out into the second region Z2, and the second coil end 292 is cooled by the refrigerant that flows out into the second region Z2. Further, since the refrigerant that has flowed out into the second region Z2 flows along the bottom wall 12a, the bottom wall 12a is cooled by this refrigerant, and the motor drive circuit 40 that is thermally coupled to the bottom wall 12a is cooled. The

  Subsequently, the refrigerant in the second region Z2 flows into the refrigerant passages 70 via the second communication ports 82h and the second openings 702 of the second end plate 82, and the rotor core 24a is moved by the refrigerant flowing through the refrigerant passages 70. To be cooled. Further, the refrigerant flowing through each refrigerant passage 70 is centrifuged into a gas-phase refrigerant and oil by the rotation of the rotor 24, and the oil moves through the rotation shaft 23 in each refrigerant passage 70 by the centrifugal force due to the rotation of the rotor 24. It is blown away in the radially outer region as a reference. The oil blown off in the radially outer region with reference to the rotating shaft 23 is stored in regions on both sides of the rib wall 70b in the refrigerant passage 70.

  Here, the radially outer region with respect to the rotation shaft 23 of the second opening 702 of each refrigerant passage 70 is covered with the second end plate 82. Therefore, the oil blown to the radially outer region with respect to the rotation shaft 23 by the centrifugal force due to the rotation of the rotor 24 on the second region Z2 side in each refrigerant passage 70 from the second region Z2 to each refrigerant passage 70. The second end plate 82 prevents the second end plate 82 from being blown away by the inflowing refrigerant. Then, the rotor core 24a is efficiently cooled by the oil stored in the regions on both sides of the ridge wall 70b in the refrigerant passage 70.

  Further, the oil flowing through each refrigerant passage 70 is dammed to the first end plate 81 by the first opening 701 of each refrigerant passage 70, and the radial direction based on the rotation shaft 23 of the first opening 701 in each refrigerant passage 70. Temporarily stored in the outer area. The rotor core 24a is further efficiently cooled by the temporarily stored oil. Further, the refrigerant flowing through each refrigerant passage 70 collides with the end wall 30e of the bearing holding portion 30a. Therefore, in the present embodiment, the end wall 30e of the bearing holding portion 30a functions as a collision wall with which the refrigerant flowing through the refrigerant passage 70 collides. Thereby, the oil that could not be completely separated from the refrigerant by the rotation of the rotor 24 is separated from the refrigerant. Therefore, the rotor core 24a is further cooled by the separated oil.

  The oil flowing through the refrigerant passage 70 flows between the bearing holding portion 30a and the rotating shaft 23. The sliding bearing 23 a is lubricated and cooled by the oil that flows between the bearing holding portion 30 a and the rotating shaft 23.

  Further, the refrigerant flowing through the refrigerant passage 70 flows out to the first region Z1 through the first opening 701 and the first communication port 81h of the first end plate 81. Then, the first coil end 291 is cooled by the refrigerant that has flowed out into the first region Z1. Thus, the stator core 26 is cooled by cooling the first coil end 291 and the second coil end 292. And the stator core 26 and the rotor core 24a are cooled, and the electric motor 19 whole is cooled.

  Then, the refrigerant in the first region Z1 is sucked into the compression chamber 22 through the suction port 30h and compressed in the compression chamber 22, and the compressed refrigerant is discharged into the discharge chamber 15. The refrigerant discharged into the discharge chamber 15 flows out to the external refrigerant circuit 60 through the discharge port 16 and is recirculated into the motor housing 12.

In the above embodiment, the following effects can be obtained.
(1) A refrigerant passage 70 that penetrates in the axial direction of the rotary shaft 23 and communicates the first region Z1 and the second region Z2 is formed in the rotor core 24a. Furthermore, a first communication port 81h that connects the first region Z1 and the refrigerant passage 70 via the first opening 701 of the refrigerant passage 70 is formed at the end of the rotor core 24a on the first region Z1 side. An end plate 81 was provided. A radially outer region of the first opening 701 with respect to the rotation shaft 23 is covered with a first end plate 81. According to this, the oil flowing through the refrigerant passage 70 is blocked by the first end plate 81 at the first opening 701 of the refrigerant passage 70 and has a diameter with reference to the rotation shaft 23 of the first opening 701 in the refrigerant passage 70. The rotor core 24a can be cooled more efficiently by the oil temporarily stored in the direction outside region and the oil stored temporarily. As a result, the cooling performance of the electric motor 19 can be improved.

  (2) A second communication port 82h that connects the second region Z2 and the refrigerant passage 70 through the second opening 702 of the refrigerant passage 70 is formed at the end of the rotor core 24a on the second region Z2 side. A two-end plate 82 was provided. A radially outer region of the second opening 702 with respect to the rotation shaft 23 is covered with a second end plate 82. According to this, the oil blown to the radially outer region with respect to the rotation shaft 23 by the centrifugal force due to the rotation of the rotor 24 on the second region Z2 side in the refrigerant passage 70 from the second region Z2 to the refrigerant passage 70. The second end plate 82 can prevent the second end plate 82 from being blown away by the refrigerant flowing into the tank. Therefore, the oil blown to the radially outer region with respect to the rotation shaft 23 by the centrifugal force due to the rotation of the rotor 24 on the second region Z2 side in the refrigerant passage 70 is easily stored in the refrigerant passage 70, and the oil Thus, the rotor core 24a can be easily cooled, and the cooling performance of the electric motor 19 can be further improved.

  (3) The end wall 30e of the bearing holding portion 30a is provided in the refrigerant passage 70 and in a radially inner region with respect to the rotation shaft 23 of the refrigerant passage 70 as a reference. According to this, the oil that could not be completely separated from the refrigerant by the rotation of the rotor 24 can be separated from the refrigerant by colliding the refrigerant flowing through the refrigerant passage 70 with the end wall 30e of the bearing holding portion 30a. Therefore, the rotor core 24a can be further easily cooled by the oil, and the cooling performance of the electric motor 19 can be further improved.

  (4) The end wall 30e of the bearing holding portion 30a is used as the collision wall. According to this, since the bearing holding part 30a is the existing structure of the electric compressor 10, it is not necessary to separately provide a member that functions as a collision wall, and the structure can be simplified. Further, since the end wall 30e of the bearing holding portion 30a is provided in the refrigerant passage 70, the electric compressor 10 of the electric compressor 10 is compared with the case where the end wall 30e of the bearing holding portion 30a is provided outside the refrigerant passage 70. The physique along the axial direction can be reduced in size.

  (5) The bearing holder 30 a and the rotary shaft 23 communicate with each refrigerant passage 70. According to this, since the oil flowing through each refrigerant passage 70 flows between the bearing holding portion 30a and the rotating shaft 23, the oil flowing between the bearing holding portion 30a and the rotating shaft 23 lubricates the slide bearing 23a. And can be cooled.

  (6) A plurality of refrigerant passages 70 are formed in the rotor core 24 a in the circumferential direction of the rotating shaft 23. Therefore, for example, the cooling performance of the electric motor 19 can be improved as compared with the case where the number of the refrigerant passages 70 is one.

  (7) Within each refrigerant passage 70 and in the radially outer region with reference to the rotation shaft 23 of each refrigerant passage 70, a rib wall 70 b extending in the axial direction in each refrigerant passage 70 is provided. According to this, the oil blown off in the radially outer region based on the rotation shaft 23 by the centrifugal force due to the rotation of the rotor 24 can be stored in the regions on both sides of the rib wall 70b in the refrigerant passage 70. it can. Therefore, it is possible to prevent the oil blown off in the radially outer region with respect to the rotation shaft 23 by the centrifugal force caused by the rotation of the rotor 24 from being locally retained in the refrigerant passage 70. The rotor core 24a can be efficiently cooled.

  (8) The compression unit 18, the electric motor 19, and the motor drive circuit 40 are arranged in this order along the axial direction of the rotary shaft 23. According to this, the motor drive circuit 40 can be cooled by the refrigerant sucked into the second region Z2 via the suction port 12h.

  (9) According to the present embodiment, since the rotor core 24a can be efficiently cooled, the cooling performance of each permanent magnet 24b embedded in the rotor core 24a can be improved. Therefore, it is not necessary to form each permanent magnet 24b from a material having high heat resistance, which can contribute to cost reduction.

  (10) The first communication port 81h and the second communication port 82h so that the inner peripheral surfaces of the first communication port 81h and the second communication port 82h are located on the radially inner side of the rotating shaft 23 with respect to the ridge wall 70b. The inner diameter was set. According to this, compared with the case where the inner peripheral surface of the 1st communicating port 81h and the 2nd communicating port 82h is located in the radial direction outer side of the rotating shaft 23 rather than the protrusion wall 70b, the 1st end plate 81 is provided. And in the 2nd end plate 82, the area which dams the oil in the area | region of the both sides which pinch | interpose the rib wall 70b in the refrigerant path 70 can be increased. As a result, the oil can be easily stored in the regions on both sides of the rib 70b in the refrigerant passage 70.

  (11) The communication between the first region Z1 and the second region Z2 between the passage forming portion 12c and the cluster block 50 is blocked by the gap filling member 51. Therefore, the refrigerant sucked into the motor housing 12 through the suction port 12h can be easily discharged to the second region Z2, and the motor drive circuit 40 is efficiently cooled by the refrigerant flowing into the second region Z2. can do. Further, since the refrigerant flowing through the refrigerant passage 70 can be increased as much as possible, the rotor core 24a can be efficiently cooled.

  (12) The first end plate 81 and the second end plate 82 also have a function of preventing the permanent magnet 24b from protruding in the axial direction of the rotary shaft 23. Therefore, the number of parts can be reduced as compared with the case where the first end plate and the second end plate are provided separately from the end plates that prevent the permanent magnets 24b from protruding in the axial direction of the rotary shaft 23.

In addition, you may change the said embodiment as follows.
In the embodiment, the second end plate 82 may be deleted. In this case, in the axial direction of the rotating shaft 23, it is necessary to separately provide an end plate for preventing each permanent magnet 24b from jumping out toward the second region Z2.

In the embodiment, the first end plate 81 and the second end plate 82 may be provided separately from the end plate that prevents the permanent magnet 24b from protruding in the axial direction of the rotation shaft 23.
In the embodiment, the end wall 30e of the bearing holding portion 30a may not be inserted into the refrigerant passage 70.

In the embodiment, a member that functions as a collision wall may be provided separately.
In the embodiment, the number of the refrigerant passages 70 is not particularly limited.
In the embodiment, a ridge wall 70b extending in the axial direction in each refrigerant passage 70 is provided in each refrigerant passage 70 and in a radially outer region with respect to the rotation shaft 23 of each refrigerant passage 70 as a reference. You may have two or more.

In the embodiment, the refrigerant passage 70 may not have the ridge wall 70b, and may be, for example, a circular refrigerant passage.
In the embodiment, the inner peripheral surfaces of the first communication port 81h and the second communication port 82h may be located on the radially outer side of the rotation shaft 23 with respect to the ridge wall 70b.

  In the embodiment, the shapes of the first communication port 81h and the second communication port 82h are not particularly limited. In short, it is sufficient that the periphery of the first communication port 81h in the first end plate 81 or the periphery of the second communication port 82h of the second end plate 82 protrudes inward from the virtual circle R1. The radially outer region of the first opening 701 with respect to the rotational shaft 23 is covered with the first end plate 81, and the radially outer region of the second opening 702 with respect to the rotational shaft 23 is the second end plate. What is necessary is just to be covered with 82.

In the embodiment, the bearing holder 30 a and the rotary shaft 23 may not communicate with each refrigerant passage 70.
In the embodiment, the gap filling member 51 may be deleted, and the first region Z1 and the second region Z2 may be communicated with each other via the passage forming portion 12c and the cluster block 50.

  In the embodiment, the compression unit 18, the electric motor 19, and the motor drive circuit 40 may not be arranged along the axial direction of the rotating shaft 23 in this order. For example, the inverter cover 41 may be fixed to the peripheral wall of the motor housing 12, and the motor drive circuit 40 may be stored in a storage space defined by the peripheral wall of the motor housing 12 and the inverter cover 41.

  In the embodiment, the compression unit 18 may be, for example, a piston type or a vane type.

  DESCRIPTION OF SYMBOLS 10 ... Electric compressor, 11 ... Housing, 12h ... Suction port, 18 ... Compression part, 19 ... Electric motor, 23 ... Rotating shaft, 23a ... Sliding bearing as a bearing, 24 ... Rotor, 24a ... Rotor core, 25 ... Stator, 26 ... Stator core, 27 ... Teeth, 27s ... Slot, 29 ... Coil, 30a ... Bearing holding part, 30e ... End wall that functions as a collision wall, 40 ... Motor drive circuit, 60 ... External refrigerant circuit, 70 ... Refrigerant passage, 70b ... rib wall, 81 ... first end plate, 81h ... first communication port, 82 ... second end plate, 82h ... second communication port, 291 ... first coil end, 292 ... second coil end, 701 ... first 1 opening, 702 ... 2nd opening, Z1 ... 1st area | region, Z2 ... 2nd area | region.

Claims (7)

A rotor that rotates integrally with the rotating shaft, an electric motor that includes a stator that surrounds the rotor and is fixed to the inner peripheral surface of the housing, a compression unit that is driven by the rotation of the rotating shaft, and drives the electric motor An electric compressor including a motor drive circuit, wherein a coil is disposed in a slot between a plurality of teeth formed in a stator core constituting the electric motor,
In the housing, there are a first region where the first coil end on the compression portion side of the coil is located, and a second region where a second coil end on the coil opposite to the compression portion side is located. The housing is formed with a suction port that opens to the second region and is connected to an external refrigerant circuit. The rotor core that forms the rotor penetrates in the axial direction of the rotating shaft. And the refrigerant path which connects the 1st field and the 2nd field is formed,
A first end plate in which a first communication port that connects the first region and the refrigerant passage through the first opening of the refrigerant passage is formed at an end of the rotor core on the first region side. Provided,
A radially outer region of the first opening with respect to the rotation axis is covered with the first end plate,
A second end plate formed with a second communication port for communicating the second region and the refrigerant passage through a second opening of the refrigerant passage is formed at an end of the rotor core on the second region side. Provided,
A radially outer region of the second opening with respect to the rotation axis is covered with the second end plate,
An electric compressor characterized in that a radially inner region of the second opening with respect to the rotation axis is not covered with the second end plate.   2. The electric compressor according to claim 1, further comprising a collision wall in the refrigerant passage and in a radially inner region with respect to the rotation axis of the refrigerant passage. The rotating shaft is supported by a bearing, and the bearing is held by a bearing holding portion provided in the housing,
The electric compressor according to claim 2, wherein the collision wall is an end wall of the bearing holding portion.   The electric compressor according to claim 3, wherein the bearing holding portion and the rotating shaft communicate with the refrigerant passage.   The electric compressor according to any one of claims 1 to 4, wherein a plurality of the refrigerant passages are formed in a circumferential direction of the rotating shaft.   2. A rib wall extending in the axial direction in the refrigerant passage in the refrigerant passage and in a radially outer region with respect to the rotation axis of the refrigerant passage. The electric compressor according to any one of claims 5 to 6.   The compression unit, the electric motor, and the motor drive circuit are arranged in this order along the axial direction of the rotating shaft. The electric compressor as described.