阅读说明：本技术 电动压缩机 (Electric compressor ) 是由 鸣田知和 于 2018-11-15 设计创作，主要内容包括：【课题】不增大驱动电动压缩机的压缩机构的电动马达整体的尺寸,就抑制线圈与定子芯之间的放电。电动压缩机的电动马达具有圆筒状的定子和在其径向内侧配置的转子。【解决方案】定子具有：定子芯(52),由圆筒状的轭部(52B)、和从其内周面向径向内侧突出且在周向上隔开既定间隔而配置的多个齿部(52A)构成；线轴状的绝缘子(54),相对于多个齿部(52A)中的各个可装卸地嵌装；线圈(56),卷绕于绝缘子；以及绝缘性部件(58),覆盖线圈(56)的卷绕状态下的外表面。(To suppress discharge between a coil and a stator core without increasing the size of an electric motor for driving a compression mechanism of an electric compressor. An electric motor of an electric compressor includes a cylindrical stator and a rotor disposed radially inward of the stator. [ solution ] A stator has: a stator core (52) that is composed of a cylindrical yoke (52B) and a plurality of teeth (52A) that protrude radially inward from the inner circumferential surface thereof and are arranged at predetermined intervals in the circumferential direction; a bobbin-shaped insulator (54) which is detachably fitted to each of the plurality of teeth (52A); a coil (56) wound around the insulator; and an insulating member (58) that covers the outer surface of the coil (56) in the wound state.)

1. An electric compressor comprising an electric motor having a rotor disposed radially inside a cylindrical stator, and a compression mechanism driven by the electric motor and compressing a refrigerant of a vehicle air conditioner,

the stator has:

a stator core including a cylindrical yoke and a plurality of teeth portions protruding radially inward from an inner circumferential surface of the yoke and arranged at predetermined intervals in a circumferential direction;

a bobbin-shaped insulator detachably fitted to each of the plurality of teeth;

a coil wound around the insulator; and

and an insulating member covering an outer surface of the coil in a wound state.

2. The electric compressor according to claim 1, wherein the insulator has:

a cylindrical body portion having both ends open and fitted to each of the plurality of teeth in a state in which the coil is wound;

a first flange portion extending outward from an opening edge of the main body portion located radially outward of the tooth portion; and

a second flange portion extending outward from an opening edge of the main body portion located radially inward of the tooth portion,

the insulating member covers the outer surface of the coil in a wound state, and also covers the peripheral edges of the first flange and the second flange.

3. The electric compressor according to claim 1 or claim 2, wherein the insulating member is a self-melting tape or a coating layer formed of a resin having electrical insulation.

4. The motor-driven compressor according to claim 3, wherein the resin is polyphenylene sulfide, polytetrafluoroethylene, polyethylene terephthalate, or an epoxy resin.

5. The electric compressor according to any one of claims 1 to 4, wherein the stator core has a split structure in which the yoke portion and the plurality of tooth portions are provided separately.

6. The electric compressor according to any one of claims 1 to 5, wherein the cylindrical yoke is configured by a plurality of arc-shaped members that are coupled to each other in a state of being arranged in a circumferential direction.

7. The electric compressor according to any one of claims 1 to 6, wherein a part or all of the plurality of teeth are integrally joined at a radially inner end thereof.

Technical Field

The present invention relates to an electric compressor used for compressing a refrigerant in an air conditioner for a vehicle.

Background

Such an electric compressor generally includes a compression mechanism that compresses a refrigerant of an air conditioner for a vehicle and an electric motor that drives the compression mechanism. As an electric motor, an electric motor described in patent document 1 is known. The electric motor described in patent document 1 is an inner rotor type electric motor in which a rotor is disposed radially inside a cylindrical stator. The stator includes: a stator core having a cylindrical yoke and a plurality of teeth portions protruding radially inward from an inner circumferential surface thereof and provided at predetermined intervals in a circumferential direction; a bobbin-shaped insulator fitted to the tooth portion; and a coil wound around the insulator.

The insulator has a square tubular body portion having both ends open and fitted to the tooth portion, an outer flange portion formed over the entire circumference of the body portion having one end open and positioned radially outward (base end side) of the tooth portion, and an inner flange portion formed over the entire circumference of the body portion having the other end open and positioned radially inward (tip end side) of the tooth portion.

Disclosure of Invention

Problems to be solved by the invention

However, for example, as the voltage of a battery for an automobile such as an electric automobile or a hybrid automobile increases, a relatively high voltage is applied to an electric motor of an electric compressor. In such an electric motor, it is required to ensure a longer insulation distance, particularly a creepage distance, which is the shortest distance along the surface of the insulating member between the conductive members, for electrically insulating the conductive members such as the coil and the stator core from each other.

Here, in the electric motor described in patent document 1, since the outer surface of the coil wound around the insulator is exposed, when a relatively high voltage is applied to the electric motor, there is a risk that the creepage distance required to electrically insulate the coil from the stator core is insufficient. If the creepage distance is insufficient, electric discharge occurs in which current flows between the outer surface of the coil and the tip of the tooth portion along the surface of the inner flange portion, and electric discharge occurs in which current flows between the outer surface of the coil and the yoke portion along the surface of the outer flange portion, and the coil coating is damaged. In order to suppress such discharge between the coil and the stator core, for example, it is conceivable to secure an appropriate creepage distance by enlarging each flange portion of the insulator to extend the shortest distance from the outer surface of the coil to the tip of the tooth portion or the yoke portion along the surface of each flange portion. However, since the size of the entire electric motor is increased by increasing the circumferential distance between the teeth to avoid interference between the insulators, it is not preferable to increase the flange portions.

Accordingly, an object of the present invention is to provide an electric compressor capable of suppressing discharge between a coil and a stator core without increasing the size of the entire electric motor.

Means for solving the problems

An electric compressor according to an aspect of the present invention includes an electric motor having a rotor disposed radially inward of a cylindrical stator, and a compression mechanism driven by the electric motor and compressing a refrigerant of an air conditioning device for a vehicle. The stator includes: a stator core including a cylindrical yoke and a plurality of teeth portions protruding radially inward from an inner circumferential surface of the yoke and arranged at predetermined intervals in a circumferential direction; a rotor disposed radially inward of the stator core; a bobbin-shaped insulator detachably fitted to each of the plurality of teeth; a coil wound around the insulator; and an insulating member covering an outer surface of the coil in a wound state.

Effects of the invention

According to the present invention, since the outer surface of the coil wound around the insulator is covered with the insulating member, it is possible to suppress discharge between the coil and the stator core without increasing the size of the entire electric motor.

Drawings

Fig. 1 is a sectional view showing an electric compressor according to an embodiment of the present invention.

Fig. 2 is a side view showing the stator.

Fig. 3 is a perspective view showing the stator.

Fig. 4 is an exploded perspective view of the stator.

Fig. 5 is a view of the stator as viewed from the inverter side.

Fig. 6 is a sectional view taken along line a-a of fig. 2.

Fig. 7 is a perspective view showing the insulator before the coil is wound.

Fig. 8 is a perspective view showing the insulator in a state where the wound coil is covered with the insulating member.

Fig. 9 is a sectional view showing the insulator in a state where the wound coil is covered with the insulating member.

Detailed Description

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

Fig. 1 is a sectional view showing an electric compressor according to an embodiment of the present invention.

The electric compressor 1 is provided in a refrigerant circuit of a vehicle air conditioner such as an electric vehicle or a hybrid vehicle, for example, and sucks, compresses, and discharges a refrigerant of the vehicle air conditioner. The electric compressor 1 is a so-called inverter-integrated compressor including an electric motor 10, a compression mechanism 20 driven by the electric motor 10 and compressing a refrigerant of an air conditioner for a vehicle, an inverter 30 for driving the electric motor 10, and a casing 40 accommodating the electric motor 10, the compression mechanism 20, and the inverter 30.

The electric motor 10 includes a cylindrical stator 50 and a rotor 60 disposed radially inward of the stator 50. That is, the electric motor 10 is a so-called inner rotor type electric motor in which the rotor 60 is disposed radially inside the stator 50. As the electric motor 10, for example, an 8-pole 12-slot type three-phase ac motor is used.

Further, the stator 50 includes: a bobbin-shaped insulator 54 fitted in each of the plurality of teeth 52A of the stator core 52, which will be described in detail later, a coil 56 (not shown in fig. 1) wound around the insulator 54, and an insulating member 58 covering an outer surface of the coil 56 in a wound state.

The rotor 60 has a plurality of magnetic poles not shown. More specifically, in the rotor 60, 4 permanent magnets are embedded in the N-pole and 4 permanent magnets are embedded in the S-pole. That is, the rotor 60 has 8 magnetic poles at equal intervals. A through hole (not shown) into which the drive shaft 60A of the electric motor 10 is inserted is formed in the radial center of the rotor 60. The rotor 60 and the drive shaft 60A are integrated by shrink fitting or the like.

The compression mechanism 20 is disposed on one end side of the drive shaft 60A. The compression mechanism 20 is a so-called scroll type compression mechanism having a fixed scroll part 22 and a movable scroll part 24 which are disposed to face each other in the direction of the center axis O shown in fig. 1, for example.

The fixed scroll part 22 is integrally formed with a volute wrap (scroll) 22B on an end plate 22A. Similarly, in the movable scroll member 24, a scroll wrap 24B is integrally formed on the end plate 24A.

The two scroll members 22, 24 are disposed such that the two scroll teeth 22B, 24B mesh, the end portion of the protruding side of the scroll tooth 22B contacts the end plate 24A, and the end portion of the protruding side of the scroll tooth 24B contacts the end plate 22A. Further, tip seals are embedded in the projecting end portions of the two scroll teeth 22B and 24B.

The two scroll members 22 and 24 are arranged such that the side walls of the two scroll wraps 22B and 24B partially contact each other in a state where the circumferential angles of the two scroll wraps 22B and 24B are offset from each other. Thereby, a crescent-shaped closed space refrigerant bag 70 is formed between the two scroll teeth 22B, 24B.

The movable scroll member 24 is coupled to one end of the drive shaft 60A, and revolves on a circular orbit around the central axis O while being prevented from rotating by a rotation preventing mechanism, not shown. That is, the movable scroll 24 rotates relative to the fixed scroll 22 by the rotation of the drive shaft 60A.

The inverter 30 converts a direct current from a vehicle battery, not shown, into an alternating current, and supplies the electric motor 10 with the alternating current.

The casing 40 includes, for example, a cylindrical center casing 42 that houses the compression mechanism 20, a cylindrical front casing 44 that is disposed in front of the center casing (leftward in fig. 1) and houses the electric motor 10 and the inverter 30, an inverter cover 46 that is disposed in front of the front casing 44, and a cylindrical rear casing 48 that is disposed behind the center casing 42 (rightward in fig. 1) and has a closed rear end. The housings 42, 44, and 48 and the inverter cover 46 are formed by casting, for example, and are integrally fastened by fastening means (not shown) such as bolts, thereby constituting the housing 40.

The center case 42 is composed of a cylindrical portion 42A and a bottom wall portion 42B. On the rear side in the center case 42, the compression mechanism 20 is disposed in a space defined by the cylindrical portion 42A and the bottom wall portion 42B. The opening at the rear side of the center housing 42 is closed by a rear housing 48.

The front housing 44 is formed of an annular peripheral wall 44A and a partition wall 44B. The inverter 30 and the electric motor 10 are disposed on the front side and the rear side of the front case 44 with the partition wall 44B interposed therebetween. An opening of the front side (the side where the inverter 30 is arranged) of the front housing 44 is closed by an inverter cover 46.

A through hole 42B1 is formed in the bottom wall 42B of the center case 42 at substantially the center thereof. One end of the drive shaft 60A is rotatably supported by the through hole 42B1 via a bearing 72. A support portion 44B1 that rotatably supports the other end of the drive shaft 60A is formed substantially at the center of the partition wall 44B of the front housing 44. Thereby, the rotor 60 of the electric motor 10 is rotatably supported radially inside the stator 50.

Further, a thrust receiving portion 42B2 that receives the end plate 24A of the movable scroll member 24 via the thrust plate 74 is provided in the bottom wall portion 42B of the center housing 42. Thereby, the movable scroll member 24 is supported in the thrust direction.

A refrigerant suction chamber (not shown) is formed inside the front housing 44. A suction port (not shown) for the refrigerant flowing from the outside of the electric compressor 1 to the suction chamber is provided in the peripheral wall portion 44A of the front housing 44. By the refrigerant flowing into the suction chamber from the suction port, the electric motor 10 radiates heat, and the electric components of the inverter 30 radiate heat via the partition wall 44B.

A refrigerant passage space 76 is formed inside the center housing 42 and the front housing 44, and the refrigerant passage space 76 extends in a direction parallel to the central axis O and guides the refrigerant from the suction chamber to the vicinity of the compression mechanism 20.

A first end face 42A1 joined to the front end face of the rear case 48 and a second end face 42A2 located radially inward of the first end face 42A1 and recessed forward in the direction of the central axis O are provided on the rear end face of the cylindrical portion 42A of the center case 42. The end plate 22A of the fixed scroll member 22 is sandwiched by the second end face 42A2 and the front end face of the rear housing 48.

Here, a discharge port 22A1 for discharging the refrigerant compressed by the compression mechanism 20 to the rear shell 48 side is formed substantially in the center of the end plate 22A of the fixed scroll member 22. The discharge port 22a1 is provided with a check valve 22a 2. A discharge chamber 48A into which the refrigerant discharged from the discharge hole 22A1 flows is formed between the rear case 48 and the end plate 22A. Further, a peripheral chamber 48B communicating with the discharge chamber 48A is formed around the discharge chamber 48A. A discharge port 48C for discharging the refrigerant passing through the discharge chamber 48A and the surrounding chamber 48B to the outside is provided in the outer wall of the rear housing 48.

Further, for example, annular gaskets (not shown) are interposed between the first end face 42A1 and the front end face of the rear case 48 and between the end plate 22A and the front end face of the rear case 48. Similarly, an annular gasket (not shown) is interposed between the front end surface of the cylindrical portion 42A of the center case 42 and the rear end surface of the peripheral wall portion 44A of the front case 44. This suppresses leakage of the refrigerant from the inside to the outside of the casing 40.

In the electric compressor 1 configured as described above, if a magnetic field is generated in the stator 50 by the power supply from the inverter 30, a rotational force acts on the rotor 60. Thereby, the drive shaft 60A is rotationally driven. Then, the rotational force of the drive shaft 60A is transmitted to the movable scroll member 24, and the movable scroll member 24 rotates. When the movable scroll member 24 rotates, the refrigerant taken into the refrigerant bladder 70 through the suction port, the suction chamber, and the refrigerant passage space 76 is compressed. The compressed refrigerant is discharged from the discharge hole 22a1 to the discharge chamber 48A, and is led out therefrom to the outside via the peripheral chamber 48B and the discharge port 48C.

The structure of the stator 50 and the insulator 54 constituting a part thereof of the electric motor 10 will be described in detail below with reference to fig. 2 to 8.

Fig. 2 is a side view showing the stator 50, fig. 3 is a perspective view showing the stator 50, fig. 4 is an exploded perspective view showing the stator 50, fig. 5 is a view of the stator 50 viewed from the inverter 30 side, and fig. 6 is a sectional view of a-a line of fig. 2. Fig. 7 is a perspective view showing the insulator 54 before the coil 56 is wound, and fig. 8 is a perspective view showing the insulator 54 in a state where the wound coil 56 is covered with the insulating member 58. In fig. 2 to 4, the compression mechanism 20 is disposed on the left side of the stator 50, and the inverter 30 is disposed on the right side.

The stator 50 includes a stator core 52 including a cylindrical yoke 52B and a plurality of teeth 52A protruding radially inward from an inner circumferential surface of the yoke 52B and arranged at predetermined intervals in the circumferential direction, the insulator 54, the coil 56, and an insulating member 58. In the 8-pole 12-slot type three-phase ac motor, for example, 12 teeth 52A are provided, and 12 slots open to the rotor 60 side are formed between the 12 teeth 52A.

Each of the plurality of teeth 52A is formed by laminating a plurality of substantially T-shaped silicon steel plates formed such that an end portion 52A1 on the radially inner side (front end side) (hereinafter simply referred to as "inner end portion") is wider than an end portion 52A2 on the radially outer side (base end side) (hereinafter simply referred to as "outer end portion") in the direction of the central axis O. The distal end surface of the inner end portion 52a1 is curved in an arc shape.

The yoke 52B is formed by, for example, laminating a plurality of silicon steel plates formed in an annular shape in the direction of the center axis O. As shown in fig. 4, a plurality of groove portions 52B1 extending in the direction of the central axis O and arranged at predetermined intervals in the circumferential direction are formed on the inner circumferential surface of the yoke portion 52B. The outer end 52A2 of each tooth 52A is pressed into the plurality of groove portions 52B 1. That is, the stator core 52 has a split structure in which the yoke portion 52B and the tooth portion 52A are provided separately.

In fig. 3 and 4, the yoke 52B is illustrated as an integrally formed cylindrical member, but the present invention is not limited thereto. For example, the yoke portion 52B may have a split structure including a plurality of (e.g., 12) arc-shaped members 52B2 divided by a broken line B in fig. 5. That is, the cylindrical yoke portion 52B may be formed of a plurality of arc-shaped members 52B2 coupled to each other in a state of being arranged in the circumferential direction. In this case, each of the plurality of teeth 52A is press-fitted into the groove portion 52B1 of each arcuate member 52B2 so as to protrude radially inward from the inner peripheral surface of each arcuate member 52B 2.

In fig. 3 to 5, the plurality of teeth 52A are provided separately, but the present invention is not limited to this. For example, the plurality of teeth 52A may be formed by connecting the inner end portions 52A1 of the teeth 52A adjacent in the circumferential direction to each other so that the inner peripheral edge defined by the inner end portions 52A1 thereof has a substantially circular shape. In this case, the plurality of teeth 52A are press-fitted into the yoke 52B in a state where the outer peripheral edge defined by the outer end 52A2 is formed in a gear shape. However, the present invention is not limited to this, and the plurality of tooth portions 52A may be press-fitted into the yoke portion 52B in a state where not all of the tooth portions 52A are coupled but two or more tooth portions 52A are coupled to each other. That is, a part or all of the plurality of teeth 52A may be integrally connected at the radially inner end (inner end 52A 1).

The insulator 54 is a resin bobbin having electrical insulation. As shown in fig. 7, the insulator 54 includes, for example, a square tubular body portion 54A having both ends open, a rectangular first flange portion 54B formed over the entire circumference of the opening edge on one end side of the body portion 54A, and a rectangular second flange portion 54C formed over the entire circumference of the opening edge on the other end side of the body portion 54A.

The body 54A has a rectangular opening and is fitted into the tooth 52A. The first flange portion 54B is positioned radially outward of the tooth portion 52A in a state where the body portion 54A is fitted in the tooth portion 52A. The second flange portion 54C is positioned radially inward of the tooth portion 52A in a state where the body portion 54A is fitted in the tooth portion 52A. As shown in fig. 5, the first flange portion 54B is longer than the second flange portion 54C in the circumferential direction of the stator core 52 when the insulator 54 is fitted in the tooth portion 52A. As shown in fig. 7, the first flange 54B is longer than the second flange 54C in the direction along the center axis O of the stator core 52 (vertical direction in fig. 7).

As shown in fig. 6, the portion of the inner diameter of the main body portion 54A located radially inward of the tooth portion 52A is widened in conformity with the shape of the inner end portion 52A1 of the tooth portion 52A. Therefore, in a state where the insulator 54 is fitted in the tooth portion 52A, the peripheral edge of the inner end portion 52A1 is surrounded by the inner wall of the body portion 54A.

The coil 56 is, for example, a copper wire with an insulating coating, and is wound around the body 54A of the insulator 54 (see fig. 6). As shown in fig. 8, the outer surface of the coil 56 wound around the insulator 54 (body 54A) (i.e., the exposed surface on the outermost outer circumferential side of the coil 56 in the wound state) is covered with an insulating member 58. After that, the outer end portions 52A2 of the respective tooth portions 52A are inserted into the respective openings on the second flange portion 54C side of the insulator 54 in the state shown in fig. 8, and the insulator 54 is detachably fitted to the respective tooth portions 52A. In this state, the outer end 52A2 of each tooth 52A is press-fitted into the groove 52B1 of the yoke 52B, thereby forming the stator 50.

The insulating member 58 is, for example, a self-melting tape made of resin having electrical insulation. In view of the ease of work in the manufacturing process of the electric motor 10, the high vibration resistance required for the vehicle air conditioner, and the like, the self-melting tape is preferably a type of self-melting tape (for example, a heat-shrinkable tape) that has low adhesion force during manufacturing and is bonded by melting the adhesive surface by heating. Then, the self-melting tape is wound around the entire circumference of the coil 56 wound around the insulator 54 (main body portion 54A), thereby covering the outer surface of the coil 56 in a wound state.

Further, as shown in fig. 9, the self-melting band is preferably wound around the respective peripheral edges of the 1 st and 2 nd flange portions 54B and 54C in addition to the outer surface of the coil 56 in the wound state. That is, the insulating member 58 may cover the peripheral edges of the first and second flange portions 54B and 54C.

However, the insulating member 58 is not limited to the self-melting tape, and may be a coating layer formed by applying an electrically insulating resin to the outer surface of the coil 56 and the peripheral edges of the flange portions 54B and 54C, or by impregnating the entire insulator 54 around which the coil 56 is wound with a resin.

Examples of the resin used for the self-melting tape and the coating layer include resins having relatively high heat resistance, oil resistance, and refrigerant resistance, in addition to electrical insulation, such as polyphenylene sulfide, polytetrafluoroethylene, polyethylene terephthalate, and epoxy resin.

The electric compressor 1 having the electric motor 10 configured as described above has the following operational advantages.

That is, since the outer surface of the coil 56 wound around the tooth portion 52A of the stator core 52 via the insulator 54 is covered with the insulating member 58, the exposed surface of the coil 56 with respect to the stator core 52 is eliminated. Accordingly, even when a relatively high voltage is applied to the electric motor 10, electric discharge in which a current flows between the outer surface of the coil 56 and the stator core 52 along the surfaces of the flange portions 54B and 54C of the insulator 54 is suppressed. More specifically, the respective constituent members can be electrically insulated from each other regardless of the shortest distance from the outer surface of the coil 56 to the inner end 52A1 of the tooth portion 52A along the surface of the second flange portion 54C and the shortest distance from the outer surface of the coil 56 to the yoke portion 52B along the surface of the first flange portion 54B, that is, the creeping distance. Further, since it is not necessary to secure an insulation distance (particularly, a creeping distance) between the coil 56 and the stator core 52, which is required when a relatively high voltage is applied to the electric motor 10, it is not necessary to increase the size of the flange portions 54B and 54C. Therefore, it is not necessary to increase the circumferential distance between the teeth 52A in order to avoid interference between the insulators 54 caused by increasing the flange portions 54B and 54C, and thus the above-described discharge can be suppressed without increasing the size of the entire motor 10.

In general, in an electric motor, electric discharge can occur not only between a coil and a stator core but also between adjacent coils. However, in the electric motor 10 configured as described above, since the outer surface of the coil 56 in the wound state is covered with the insulating member 58, the discharge between the adjacent coils 56 can be suppressed. Therefore, the circumferential distance between the adjacent tooth portions 52A can be shortened, and the size of the entire electric motor 10 can be reduced.

Further, the insulating member 58 covers the outer surface of the coil 56 wound around the tooth portion 52A via the insulator 54 over the entire circumference. Thus, in the electric compressor 1, the components of the electric compressor 1 close to the coil 56, such as the peripheral wall portion 44A and the partition wall 44B of the front housing 44 and the bottom wall portion 42B of the center housing 42, are electrically insulated from the coil 56. Therefore, since the discharge between the coil 56 and the components of the electric compressor 1 can be suppressed, the size of the entire electric compressor 1 can be reduced, for example, by reducing the accommodation space in the housing 40.

In the above description, the peripheral edges of the first and second flange portions 54B and 54C of the insulator 54 are covered with the insulating member 58, in addition to the outer surface of the coil 56 in the wound state. This can more effectively eliminate the gap between the coil 56 and the first and second flange portions 54B and 54C. Therefore, it is possible to more effectively suppress electric discharge that flows between the outer surface of the coil 56 and the inner end 52A1 of the tooth 52A or the yoke 52B along the surface of each flange 54B, 54C due to the current passing through the gap.

Further, in the above description, the stator core 52 has a split structure in which the yoke portion 52B and the tooth portion 52A are provided separately. The insulator 54 is detachably fitted to the tooth portion 52A. Thus, when maintenance of the electric motor 10 is performed or the coil 56 is damaged, the insulator 54 removed from the tooth 52A can be inspected or replaced with the insulator 54 around which a new coil 56 is wound after the tooth 52A is removed from the yoke 52B.

The embodiments shown in the drawings are merely illustrative of the present invention, and it is needless to say that the present invention includes various improvements and modifications of the present invention by those skilled in the art within the scope of the claims, in addition to the contents directly shown by the embodiments described above.

Description of the symbols

1 electric compressor

10 electric motor

50 stator

52 stator core

52A multiple teeth

52A1 inboard end

52B yoke part

52B2 arc-shaped component

54 insulator

54A body part

54B first brush part

54C second brush part

56 coil

58 insulating member

60 rotor.