MOTOR

A motor includes a rotor and a stator having a tubular stator core, first and second electrical insulators arranged on first and second axial ends of the stator care and a stator winding. Each of the first and second electrical insulators includes an outer wall part, inner wall parts and body parts. The stator winding includes first, second and third phase stator windings and each of the windings has winding parts respectively wound around teeth of the stator core, a first lead part and a second lead part. Each of the first lead parts is connected to a power supply, and each of the second lead parts is connected in common to a neutral point part. The outer wall part of the first electrical insulator assembly includes a first movement restriction part that restricts movement of the neutral point part.

The present application claims priority to Japanese patent application serial number JP 2023-053999 filed on Mar. 29, 2023, the contents of which are incorporated fully herein by reference.

TECHNICAL FIELD

The present disclosure relates to a motor that includes a first lead part connected to a power supply and a second lead part connected to a common point.

BACKGROUND

In various devices such as compressors or the like, a motor including star-connected U-phase, V-phase and W-phase stator windings (coils) is used. For example, WO 2017-138534 A1 (a family member of U.S. Pat. No. 10,680,482 B2) discloses a compressor with a motor including star-connected phase stator windings. The compressor disclosed in WO2017-138534 includes a housing, and a compression mechanism part and a motor that are housed in the housing. The motor includes a stator and a rotor. The stator includes a stator core, electrical insulator assemblies (referred to as “resin bobbins”, “polymer bobbins”, “bobbins” or “insulators”) that are respectively arranged on first and second sides of the stator core in an axial direction, and a stator winding. The stator winding includes U-phase, V-phase and W-phase stator windings. Each of the phase stator windings has winding parts, a first lead part and a second lead part. The winding parts are respectively wound around the teeth of the stator core in a state in which the electrical insulator assemblies are arranged on both sides of the stator core in the axial direction. The first lead parts are connected to a power supply, and the second lead parts are connected to a common point. Thus, the phase stator windings are star-connected.

In such a motor, the second lead parts connected in common could move and come into contact with nearby electrical components. Therefore, in the motor disclosed in WO 2017-138534 A1, in order to restrict movement of the second lead parts, a guide member that is configured to hold the second lead parts is provided on the opposite side of one of the electrical insulator assemblies to the stator core.

SUMMARY

The motor disclosed in WO 2017-138534 A1 needs the guide member that holds the second lead parts. Further, it is necessary to mount the guide member to (on) the electrical insulator assembly and to wire the second lead parts to the guide member that is formed separately from the electrical insulator assembly.

Accordingly, it is one non-limiting object of the present disclosure to disclose techniques for easily restricting (preventing, blocking, restraining, limiting) movement of the lead parts connected in common using a simple structure.

The present disclosure relates to a motor that comprises a rotor and a stator.

The stator includes a tubular stator core extending in an axial direction, first and second electrical insulator assemblies that are respectively arranged (disposed) on first and second sides of the stator core in the axial direction, and a stator winding.

The stator core includes a yoke extending in a circumferential direction around an axis of the stator core, and teeth each extending radially inward from the yoke.

Each of the first and second electrical insulator assemblies includes an outer wall part, inner wall parts and body parts. The outer wall part extends in the circumferential direction and the axial direction. The inner wall parts are arranged radially inward of the outer wall part and are placed at positions spaced apart from each other in the circumferential direction and extend in the circumferential direction and the axial direction. The body parts are arranged on the stator core side in the axial direction between the outer wall part and the inner wall parts and extend radially.

The stator winding includes first, second and third phase stator windings. Each of the phase stator windings includes at least one winding part (winding, coil), a first lead part and a second lead part. Each winding part is formed by a lead wire wound around a respective one of the teeth of the stator core in a state in which the first and second electrical insulator assemblies are respectively arranged (disposed) on the first and second sides of the stator core in the axial direction. The first lead parts are connected to a power supply, and the second lead parts are connected to a common point. Thus, the phase stator windings are star-connected.

The stator winding includes a neutral point part (common point) to which the second lead parts of the phase stator windings are connected in common.

Furthermore, the outer wall part of the first electrical insulator assembly includes at least one movement restriction part that restricts (prevents, limits, blocks, retrains) movement of the neutral point part.

In the motor of this disclosure, the at least one movement restriction part that restricts movement of the second lead parts is provided on the outer wall part of the first electrical insulator assembly. Thus, movement of the second lead parts can be easily restricted (prevented, limited, blocked, retrained) using a simple structure.

In another aspect of the motor according to this disclosure, the at least one movement restriction part may comprise at least one first movement restriction part. The at least one first movement restriction part may be configured to restrict the neutral point part from moving radially inward and radially outward and toward the second side (stator core side) in the axial direction. When two or more first projections are provided, the projections are placed at positions spaced apart from each other in the circumferential direction.

In this aspect, the second lead parts can be restricted from moving radially inward and radially outward and toward the second side in the axial direction using a simple structure.

In another aspect of the motor according to this disclosure, the outer wall part of the first electrical insulator assembly may include at least one first projection protruding toward the first side (the opposite side to the stator core) in the axial direction.

Furthermore, at least one first projection may have a groove that extends in the circumferential direction and is open on the first side (the opposite side to the stator core) in the axial direction. The groove may be configured such that the neutral point part can be inserted therein.

The at least one first movement restriction part may include the groove formed (defined, provided) on the at least one first projection.

In this aspect, the second lead parts can be restricted from moving radially inward and radially outward and toward the second side in the axial direction using a simple structure.

In another aspect of the motor according to this disclosure, the first movement restriction part may be configured to restrict (prevents, limits, blocks, retrains) movement of the neutral point part toward at least one of the first and second sides in the circumferential direction.

In this aspect, the second lead parts are restricted (prevented, limited, blocked, retrained) from moving radially inward and radially outward and toward the second side in the axial direction and toward at least one of the first and second sides in the circumferential direction.

In another aspect of the motor according to this disclosure, the groove formed (defined, provided) on the at least one first projection may be closed on at least one of the first and second sides in the circumferential direction.

In this aspect, the second lead parts can be restricted from moving radially inward and radially outward and toward the second side in the axial direction and toward at least one of the first and second sides in the circumferential direction using a simple structure.

In another aspect of the motor according to this disclosure, the groove formed on the at least one first projection may be open on at least one of the first and second sides in the circumferential direction.

In this aspect, the neutral point part can be easily inserted into the groove.

In another aspect of the motor according to this disclosure, the at least one movement restriction part may comprise at least one second movement restriction part. The at least one second movement restriction part may be configured to restrict circumferential movement of the neutral point part in at least one direction.

In this aspect, the second lead parts can be restricted from moving radially inward and radially outward and toward the second side in the axial direction and toward at least one side in the circumferential direction using a simple structure.

In another aspect of the motor according to this disclosure, the outer wall part of the first electrical insulator assembly may include at least one first projection and at least one second projection protruding toward the first side (the opposite side to the stator core) in the axial direction. The at least one first projection may have a groove that extends in the circumferential direction and is open on the first side (the opposite side to the stator core) in the axial direction. The groove may be configured such that the neutral point part can be inserted therein. The at least one second projection may be circumferentially spaced apart from the at least one first projection.

In this aspect, the second lead parts can be restricted from moving radially inward and radially outward and toward the second side in the axial direction and toward at least one side in the circumferential direction using a simple structure.

In another aspect of the motor according to this disclosure, the groove formed on the at least one of the projections may be open on the first and second sides in the circumferential direction.

In this aspect, the neutral point part can be more easily inserted into the groove.

In another aspect of the motor according to this disclosure, the outer wall part of the first electrical insulator assembly may include second movement restriction parts on each of the first and second sides of the at least one of the projections in the circumferential direction.

The second movement restriction part arranged (disposed) on the first side in the circumferential direction may be configured to restrict (prevent, limit, block, retrain) movement of the neutral point part toward the first side in the circumferential direction, and the second movement restriction part arranged (disposed) on the second side in the circumferential direction may be configured to restrict (prevent, limit, block, retrain) movement of the neutral point part toward the second side in the circumferential direction.

In this aspect, movement of the second lead parts toward the first and second sides in the circumferential direction can be easily restricted (prevented, limited, blocked, retrained).

In another aspect of the motor according to this disclosure, the second movement restriction part may include the projections other than the at least one of the projections.

In this aspect, the second movement restriction part can be easily formed.

In another aspect of the motor according to this disclosure, the neutral point part may include a neutral point bus bar to which the second lead parts are connected.

The neutral point bus bar may be formed (composed) of an electrically conductive material, such as a metal.

In this aspect, the neutral point part can be easily formed.

In another aspect of the motor according to this disclosure, the stator may include a cover. The cover may be arranged (disposed) on the first side (the opposite side to the stator core) of the first electrical insulator assembly in the axial direction.

In this aspect, movement of the neutral point part to the first side (the opposite side to the stator core) in the axial direction can be restricted (prevented, limited, blocked, retrained).

Thus, in motors of the present disclosure, movement of the lead parts connected in common can be easily restricted (prevented, limited, blocked, retrained) using a simple structure.

DETAILED DESCRIPTION OF THE EMBODIMENT

A representative embodiment of a motor according to the present disclosure will be described with reference to the drawings.

In this description, the term “axial direction” refers to an extending direction (shown by X inFIGS.1and2) of an axis P of a stator core100. The axis P of the stator core100corresponds to a rotation center line (rotational axis) of a rotor50when the rotor50is arranged to be rotatable relative to a stator40.

The term “circumferential direction” refers to a circumferential direction (shown by Y inFIG.2) around the axis P as viewed from one side in the axial direction.

The term “radial direction” refers to an extending direction of any line passing through the axis Pas viewed from the one side in the axial direction. The term “inner side (inside, inward) in the radial direction” or “radially inner side” refers to the axis P side in the radial direction and the term “outer side (outside, outward) in the radial direction” or “radially outer side” refers to the opposite side to the axis P in the radial direction.

As for electrical insulator assemblies (a first electrical insulator assembly200, a second electrical insulator assembly300) and cover500, the terms “axial direction”, “circumferential direction” and “radial direction” respectively refer to the “axial direction”, “circumferential direction” and “radial direction” in a state in which the electrical insulator assemblies and the cover50are mounted on the stator core100.

Furthermore, inFIG.1, the side shown by arrow X1(upper side inFIG.1) and the side shown by arrow X2(lower side inFIG.1) are defined as a “first side in the axial direction” and a “second side in the axial direction”, respectively.

Furthermore, inFIGS.1and2, the side (clockwise side) shown by arrow Y1and the side (counterclockwise side) shown by arrow Y2are defined as a “first side in the circumferential direction” and a “second side in the circumferential direction”, respectively.

The “first side in the axial direction” and the “second side in the axial direction” may be defined in reverse, and the “first side in the circumferential direction” and the “second side in the circumferential direction” may be defined in reverse.

A compressor10of one embodiment of the present teachings and a motor30of one embodiment of the present teachings that can be advantageously used in the compressor10will be described with reference toFIGS.1to16.

The compressor10includes a housing20, the motor30and a compression mechanism part80. The motor30and the compression mechanism part80are housed in a housing interior space that is defined by a housing inner peripheral surface21of the housing20. The housing interior space is closed.

The housing20is provided with a suction pipe22and a discharge pipe23.

The compression mechanism part80compresses a working medium (such as a “refrigerant” or a “coolant”) for transferring thermal energy. For example, an HFC (hydrofluorocarbon) refrigerant may be used as the working medium.

The compression mechanism part80includes a cylinder81, an eccentric rotor82that is rotated by a rotary shaft70, and a compression chamber83. The rotary shaft70is rotatably supported by bearings84,85. When the eccentric rotor82is rotated by rotation of the rotary shaft70, the working medium drawn through the suction pipe22is compressed within the compression chamber83. Then, the compressed working medium is discharged from the discharge pipe23via an outlet port83aand a passage provided in the motor30.

The arrangement position (the arrangement position in the up-down direction or in the left-right direction) of the compression mechanism part80and the motor30can be appropriately changed. A known compression mechanism part can be used as the compression mechanism part.

The motor30includes a stator40and a rotor50.

The rotor50includes a rotor core60and a rotatable shaft70. The rotor core60has a tubular shape and has a rotor core inner peripheral surface61and a rotor core outer peripheral surface62. The rotatable shaft70is inserted (for example, press-fitted) into a rotatable shaft insertion hole that is defined by the rotor core inner peripheral surface61.

The stator40includes a stator core100, the first electrical insulator assembly200, the second electrical insulator assembly300, a stator winding400, a neutral point bus bar410and a cover500, as will be described in further detail below.

The stator core100is formed (composed) of a stack of laminated electromagnetic steel sheets.

The stator core100has a tubular shape extending along the axis P of the stator core100.

The stator core100has stator core end surfaces100A and100B on the first and second sides in the axial direction, respectively, and has a stator core outer peripheral surface102on the radially outer side and a stator core inner peripheral surface on the radially inner side. The stator core inner peripheral surface is formed by tooth tip surfaces122a(described below) of each of a plurality of teeth120.

The stator core100includes a yoke110and the teeth120as shown inFIG.2.

The yoke110extends in the circumferential direction around the axis P. The teeth120are spaced apart from each other in the circumferential direction and extend radially inward from the yoke110.

Each of the teeth120has a tooth base121and a tooth tip122. Each tooth base121extends radially inward from the yoke110. Each tooth tip122is formed (provided, disposed, defined) on the radially inner side of the corresponding tooth base121and extends in the circumferential direction. The tooth tip122has a circular-arc-shaped tooth tip surface122aon the radially inner side.

Pairs of the teeth120that are adjacent to each other in the circumferential direction respectively define slots130therebetween.

The tooth tip surfaces122aform (define) the stator core inner peripheral surface. Furthermore, the tooth tip surfaces122adefine a stator core interior space100ain which the rotor50(rotor core60) is arranged (disposed).

The stator core100is housed in the housing interior space with the stator core outer peripheral surface102in close contact with the housing inner peripheral surface21. In this embodiment, the housing inner peripheral surface21and the stator core outer peripheral surface102have a circular (or generally circular) section.

Parts of the circular (or generally circular) stator core outer peripheral surface102are flattened to form flat (notched) surfaces103. The flat surfaces103and the housing inner peripheral surface21define a passage104extending in the axial direction. The cooling medium flows through the passage104.

The cross-sectional shapes of the housing inner peripheral surface21, the stator core outer peripheral surface102and the passage104can be appropriately changed.

The first electrical insulator assembly200and the second electrical insulator assembly300are formed (composed) of a material having electrical insulating properties. In this embodiment, a polymer having electrical insulating properties is used.

The first electrical insulator assembly200(hereinafter simply referred to as a “first assembly200”) is arranged on the first side of the stator core100in the axial direction such that an end surface200A of the first assembly200faces the stator core end surface100A.

As shown inFIG.4, the first assembly200has an outer wall part210, inner wall parts220and body parts230.

The outer wall part210extends in the circumferential direction and the axial direction.

The inner wall parts220are arranged radially inward of the outer wall part210and are spaced apart from each other in the circumferential direction and extend in the circumferential direction and the axial direction.

The body parts230are arranged on the second side (the stator core100side) in the axial direction between the outer wall part210and the inner wall parts220and extend radially.

The outer wall part210, the inner wall parts220and the body parts230define a recess201that extends in the circumferential direction between the outer wall part210and the inner wall parts220and is open on the first side (the opposite side to the stator core100) in the axial direction. In this embodiment, the first assembly200is arranged on the first side of the stator core100in the axial direction such that the outer wall part210, the body parts230and the inner wall parts220face the yoke110, the tooth bases121and the tooth tips122of the stator core100, respectively.

The outer wall part210has notches212extending in the circumferential direction. The outer wall part210has projections211respectively formed (provided, disposed) between the circumferentially adjacent notches212that extend in the circumferential direction and protrude toward the first side in the axial direction (the opposite side to the stator core100).

Crossover parts401a,401b,401c(described below) of the stator winding400are drawn out from the inside to the outside of the outer wall part210or drawn back from the outside to the inside of the outer wall part210through the notches212, as can be seen inFIG.3.

Guide grooves213A,213B,213C are formed (provided, defined) on an outer peripheral surface of the outer wall part210and extend in the circumferential direction, as can also be seen inFIG.3. The guide grooves213A,213B,213C are spaced apart from each other in the axial direction. The crossover parts401a,410b,401cdrawn out from the inside to the outside of the outer wall part210through the notches212are arranged along the outer peripheral surface of the outer wall part210. At this time, the crossover parts401a,401b,401care respectively guided through any one of the guide grooves213A,213B,213C and thereby prevented (blocked, restrained) from coming into contact with each other. The guide grooves213A,213B,213C are each separated into parts by the notches212.

The positions in the circumferential direction, the lengths in the circumferential direction and the depths in the axial direction of the notches212(the positions in the circumferential direction and the lengths in the circumferential direction of the projections211) are set based on positions where the crossover parts401a,401b,401care drawn out from the inside to the outside of the outer wall part210or drawn back from the outside to the inside of the outer wall part210.

The outer wall part210has a first movement restriction part (first movement restricting part, first movement preventing part) and a second movement restriction part (second movement restricting part, second movement preventing part).

The first movement restriction part restricts (prevents, blocks, restrains, limits) a neutral point bus bar410(described below), which forms a neutral point of the stator winding400, from moving radially inward and outward and toward the second side (the stator core100side) in the axial direction.

The second movement restriction part restricts (prevents, blocks, restrains, limits) the neutral point bus bar410from moving toward the first and second sides in the circumferential direction.

First, the first movement restriction part will be described.

At least one of the projections211has a groove extending in the circumferential direction. In this embodiment, as shown inFIGS.3,5and6, two projections211A and211B adjacent in the circumferential direction have respective grooves211aand211b.

The groove211ais formed (defined) at (on, in) an end surface of the projection211A on the first side (the opposite side to the stator core100) in the axial direction and is open on the first side (the opposite side to the stator core100) in the axial direction and on the first and second sides in the circumferential direction. Specifically, the groove211ahas wall surfaces on the radially inner and outer sides and on the second side in the axial direction.

Similarly, the groove211bis formed (defined) at (on, in) an end surface of the projection211B on the first side in the axial direction and is open on the first side in the axial direction and the first and second sides in the circumferential direction. Specifically, the groove211bhas wall surfaces on the radially inner and outer sides and on the second side in the axial direction.

The grooves211a,211bare formed such that the neutral point bus bar410can be inserted in the grooves211a,211bof two adjacent projections211A,211B while spanning (straddling) the notch212between the projections211A,211B.

The wall surfaces of the grooves211a,211brestrict (prevent, block, restrain, limit) the neutral point bus bar410inserted in the grooves211a,211bfrom moving radially inward and outward and toward the second side in the axial direction.

In this embodiment, the projections211A,211B are examples of an “at least one projection” according to this disclosure. The grooves211a,211brespectively formed (defined) in the projections211A,211B correspond to a “first movement restriction part that is configured to restrict (prevent, block, restrain, limit) the neutral point part from moving inward and outward in the radial direction and toward the stator core side in the axial direction” according to this disclosure.

Next, the second movement restriction part will be described.

In this embodiment, the projections211other than the projections211A,211B having the respective grooves211a,211bare configured to restrict (prevent, block, restrain, limit) the neutral point bus bar410from moving toward the first and second sides in the circumferential direction.

Specifically, a projection211C is formed on the first side of the projection211A in the circumferential direction, which projection211A is arranged on the first side of the projection211B in the circumferential direction and is configured to restrict (prevent, block, restrain, limit) the neutral point bus bar410in the grooves211a,211bfrom moving toward the first side in the circumferential direction.

For example, when the neutral point bus bar410is in the grooves211a,211band moves toward the first side in the circumferential direction, the neutral point bus bar410abuts on an abutment part of the projection211C and thereby is restricted from moving further toward the first side in the circumferential direction.

Furthermore, a projection211D is formed (defined) on the second side of the projection211B in the circumferential direction, which projection211B is arranged on the second side of the projection211A in the circumferential direction and is configured to restrict (prevent, block, restrain, limit) the neutral point bus bar410in the grooves211a,211bfrom moving toward the second side in the circumferential direction.

For example, when the neutral point bus bar410is inserted in the grooves211a,211band moves toward the second side in the circumferential direction, the neutral point bus bar410abuts on an abutment part of the projection211D and thereby is restricted from further moving toward the second side in the circumferential direction.

In this embodiment, the projection211C corresponds to a “second movement restriction part that is arranged on the first side of at least one of the projections in the circumferential direction and is configured to restrict (prevent, block, restrain, limit) movement of the neutral point part toward the first side in the circumferential direction” according to this disclosure. The projection211D corresponds to a “second movement restriction part that is arranged on the second side of at least one of the projections in the circumferential direction and configured to restrict (prevent, block) movement of the neutral point part toward the second side in the circumferential direction” according to this disclosure.

The second electrical insulator assembly300(hereinafter simply referred to as a “second assembly300”) is arranged (disposed) on the second side of the stator core100in the axial direction such that an end surface300A of the second assembly300faces the stator core end surface100B, as can be seen inFIGS.1and3.

Like the first assembly200, the second assembly300has an outer wall part310, inner wall parts320and body parts230(seeFIG.1).

The outer wall part310, the inner wall parts320and the body parts330define a recess301that extends in the circumferential direction between the outer wall part310and the inner wall parts320and is open on the second side (the opposite side to the stator core100) in the axial direction.

In this embodiment, the crossover parts401a,401b,401cbetween winding parts are arranged along the outer peripheral surface of the outer wall part210of the first assembly200, as described below.

Therefore, parts correspond respectively to the projections211, the notches212and the guide grooves213A to213C formed in the outer wall part210of the first assembly200can be omitted in the outer wall part310of the second assembly300.

The second assembly300may of course have the same shape or configuration as the first assembly200.

The stator winding400includes a U-phase stator winding (coils), a V-phase stator winding (coils) and a W-phase stator winding (coils).

As shown inFIGS.3,5and6, the U-, V- and W-phase stator windings400include winding parts (coils), first lead parts400U1,400V1and400W1and second lead parts400U2,400V2and400W2. Each of the winding parts is formed by a lead wire composed of a conductive material (such as a copper wire) being wound around the respective tooth120(specifically, the tooth bases121) of the stator core100in a state in which the first and second assemblies200,300are respectively arranged (disposed) on the first and second sides of the stator core in the axial direction.

Each of the phase stator windings includes stator winding portions connected in series or in parallel.

Each of the stator winding portions has at least one winding part (coil).

Each winding part has a winding start end and a winding finish end.

Winding start part (wire) extends from the winding start end of the winding part.

Winding finish part (wire) extends from the winding finish end of the winding part.

The first lead parts (first lead wires)400U1,400V1and400W1of each of the phase stator windings are selected from the winding start parts connected to winding parts that form the U-, V- and W-phase stator windings. The second lead parts (second lead wires)400U2,400V2and400W2of each of the phase stator windings are selected from the winding finish parts connected to winding parts that form the U-, V and W-phase stator windings.

The winding start parts and the winding finish parts that are not respectively selected as the first lead parts and the second lead parts are used as the crossover parts (crossover wires)401a,401b,401c(seeFIG.3) that connect and extend between the winding parts.

In this embodiment, the crossover parts401a,401b,401care drawn out from the inside to the outside of the outer wall part210through any of the notches212of the outer wall part210of the first assembly200. Then, the crossover parts401a,401b,401care guided by the guide grooves213A,213B,213C formed on the outer peripheral surface of the outer wall part210and arranged along the outer peripheral surface of the outer wall part210. Subsequently, the crossover parts401a,410b,401care drawn back from the outside to the inside of the outer wall part210through any of the other notches212.

In this embodiment, the first lead parts400U1,400V1and400W1of the U-, V and W-phase stator windings are connected to a power supply. The second lead parts400U2,400V2and400W2of the U-, V and W-phase stator windings are connected in common to the neutral point bus bar410so that the neutral point bus bar410forms (provides, defines) a neutral point. Thus, the U-, V and W-phase stator windings are star-connected.

In this embodiment, the U-phase stator winding, V-phase stator winding and W-phase stator winding correspond to examples of “stator windings of first, second and third phases” according to this disclosure. The first lead parts400U1,400V1and400W1correspond to examples of “first lead parts connected to a power supply” according to this disclosure. The second lead parts400U2,400V2and400W2correspond to examples of “second lead parts connected in common” according to this disclosure.

The second lead parts400U2,400V2and400W2connected in common are routed in the circumferential direction within the recess201of the first assembly200.

The second lead parts400U2,400V2and400W2, if not restricted from moving, could potentially move and come into contact with any other electrical component. Therefore, the movement of the second lead parts400U2,400V2and400W2needs to be restricted.

The structures for restricting (preventing, blocking, limiting, restraining) movement of the second lead parts400U2,400V2and400W2in the motor of this embodiment will be described with reference toFIGS.3and5to7.

In this embodiment, the second lead parts400U2,400V2and400W2of the respective phases are connected to the neutral point bus bar410.

The neutral point bus bar410is formed (composed) of a conductive material. In this embodiment, the neutral point bus bar410is formed (composed) of copper.

The neutral point bus bar410is configured to be insertable in the grooves211a,211bformed in the projections211A,211B of the first assembly200, while spanning (straddling) the notch212between the projections211A,211B. For example, the neutral point bus bar410is formed in a plate-like shape extending in an arc so as to be insertable in the grooves211a,211b.

Furthermore, the neutral point bus bar410has a length shorter than a distance between the projections211C and211D, which together serve as the second movement restriction part, in the circumferential direction.

The neutral point bus bar410can be formed (produced) by various methods. For example, it can be formed by pressing (stamping, rolling) a round bar or a copper plate, or it can be formed from a wire that is round or square wire or that has another shape.

In this embodiment, the neutral point bus bar410to which the second lead parts400U2,400V2and400W2are connected in common constitutes a “neutral point part to which the second lead parts of the stator windings of the first to third phases are connected in common” according to this disclosure.

The neutral point bus bar410is inserted into the grooves211a,211bformed in the projections211A,211B of the outer wall part210of the first assembly200with the second lead parts400U2,400V2and400W2connected to the neutral point bus bar410.

Alternatively, the second lead parts400U2,400V2and400W2may be connected to the neutral point bus bar410with the neutral point bus bar410inserted into the grooves211a,211b.

A known connecting method is used to connect the second lead parts400U2,400V2and400W2to the neutral point bus bar410.

In this state, the wall surfaces of the groove211a,211brestrict the neutral point bus bar410from moving radially inward and outward and toward the second side (the stator core100side) in the axial direction. Furthermore, the projection211C restricts the neutral point bus bar410from moving toward the first side in the circumferential direction, and the projection211D restricts the neutral point bus bar410from moving toward the second side in the circumferential direction.

In this embodiment, the grooves211a,211bformed (defined) in the projections211A,211B of the outer wall part210of the first assembly200and the projections211C,211D of the outer wall part210of the first assembly200restrict movement of the neutral point bus bar410to which the second lead parts400U2,400V2and400W2are connected in common.

Thus, movement of the second lead parts400U2,400V2and400W2can be easily restricted using a simple structure.

The cover500is arranged on the first side (the opposite side to the stator core100) of the first assembly200in the axial direction, as shown inFIG.1.

The cover500is formed (composed) of a material having electrical insulating properties. In this embodiment, the cover500is formed (composed) of a polymer having electrical insulating properties.

The structure of the cover500will now be described in further detail with reference toFIGS.9to13.

The cover500includes a peripheral (circumferential) wall510and a top wall520.

The peripheral wall510extends in the circumferential direction and the axial direction and has a circular inner peripheral surface and a circular outer peripheral surface. The peripheral wall510is arranged (disposed, located) outside of the outer wall part210(the crossover parts401a,401b,401c) of the first assembly200in a state in which the crossover parts401a,401b,401care respectively inserted in the guide grooves213A,213B,213C formed on the outer peripheral surface of the outer wall part210of the first assembly200.

The top wall520is connected to an end of the peripheral wall510on the first side (the opposite side to the stator core100) in the axial direction and extends radially and in the circumferential direction. In this embodiment, the top wall520extends in a direction orthogonal (or substantially orthogonal) to the axial direction. The top wall520has an opening520ain its center. The first lead parts400U1,400V1and400W1through the opening520aof the top wall520.

The cover500is detachably mounted on the first assembly200via mounting mechanisms at a plurality of positions spaced apart from each other in the circumferential direction.

In this embodiment, each of the mounting mechanisms includes a locking piece having a claw and an engagement recess configured to be engaged with the claw of the locking piece. In this embodiment, the locking piece is formed in (on) the peripheral wall510of the cover500, and the engagement recess is formed in the outer wall part210of the first assembly200.

Furthermore, in this embodiment, two different mounting mechanisms (first and second mounting mechanisms) are provided, each including a locking piece with a claw and an engagement recess. An appropriate one of the mounting mechanisms is selectively used according to the mounting position.

First, the first mounting mechanism will be described.

As shown inFIGS.11,13and15, the first mounting mechanism includes a first locking piece530formed (provided, disposed) on the peripheral wall510of the cover500and a first engagement recess240formed in the outer wall part210of the first assembly200.

The first locking piece530extends in the axial direction. The first locking piece530has an end part530aon the first side (the opposite side to the stator core100) in the axial direction that is a fixed end fixed to the peripheral wall510and an end part530bon the second side (the stator core100side) in the axial direction that is a free end. The first locking piece530is configured such that the end part (free end)530bon the second side in the axial direction can be elastically deformed in a radial direction relative to the end part (fixed end)530aon the first side in the axial direction.

The first locking piece530has a claw531on the end part530bon the second side (the stator core100side) in the axial direction. The claw531has a locking surface (engagement surface)531aand an inclined (cam) surface531b. The inclined surface531bis inclined radially inward toward the first side in the axial direction from an end on the second side in the axial direction. The locking surface531aextends radially outward from an end of the inclined surface531bon the first side in the axial direction. In this embodiment, the locking surface531aextends in a direction orthogonal (or substantially orthogonal) to the axial direction.

As shown inFIG.15, the first locking piece530has the claw531protruding radially inward.

The first engagement recess240is formed at an end part of the outer peripheral surface of the outer wall part210of the first assembly200on the second side in the axial direction and is open on the radially outer side and the second side in the axial direction. The first engagement recess240has a locking surface (engaged surface)240athat extends in the direction orthogonal (or substantially orthogonal) to the axial direction on the first side in the axial direction and configured to be engageable (engaged) with (by) the locking surface531aof the claw531of the first locking piece530.

Next, the second mounting mechanism will be described.

As shown inFIGS.12,14and16, the second mounting mechanism includes a second locking piece550formed (provided, disposed) in (on) the peripheral wall510of the cover500and a second engagement recess250formed (provided, defined) in in the outer wall part210of the first assembly200.

The second locking piece550extends in the axial direction. The second locking piece550has an end part550a(fixed end) on the first side (the opposite side to the stator core100) in the axial direction that is a fixed end fixed to the peripheral wall510and an end part550bon the second side (the stator core100side) in the axial direction that is a free end. The second locking piece550is configured such that the end part (free end)550bon the second side in the axial direction can be elastically radially deformed relative to the end part (fixed end)550aon the first side in the axial direction.

The second locking piece550has a claw551on the end part550bon the second side (the stator core100side) in the axial direction. The claw551has a locking surface (engagement surface)551aand an inclined (cam) surface551b. The inclined surface551bis inclined radially outward toward the first side in the axial direction from an end on the second side in the axial direction. The locking surface551aextends radially inward from an end of the inclined surface551bon the first side in the axial direction. In this embodiment, the locking surface551aextends in a direction orthogonal (or at least substantially orthogonal) to the axial direction.

The second locking piece550has the claw551that protrudes radially outward.

As shown inFIGS.4and6, a projection260is formed at a position on an end part of the outer wall part210of the first assembly200on the second side in the axial direction where the engagement recess250is formed. The projection260protrudes radially outward. The second engagement recess250is formed in the projection260.

As shown inFIG.16, the second engagement recess250has an insertion opening250A formed on the first side in the axial direction through which the claw551of the second locking piece550is insertable. In the second engagement recess250, a locking surface (engaged surface)250aextending radially outward from an end of the insertion opening250A on the second side in the axial direction is formed. The locking surface250ais configured so as to be engageable (engaged) with (by) the locking surface551aof the claw551of the second locking piece550.

As shown inFIGS.4and7, the projection260of the first assembly200has a positioning projection261protruding toward the second side in the axial direction. The positioning projection261extends in the axial direction.

Furthermore, a positioning recess140is formed on the outer peripheral surface102of the stator core100. The positioning recess140extends in the axial direction and is open on the first side in the axial direction such that the positioning projection261is insertable therein. In this embodiment, the positioning recess140has an opening to the end surface100A of the stator core100on the first side in the axial direction.

When arranging the first assembly200on the first side of the stator core100in the axial direction, the positioning projection261formed on the projection260of the first assembly200is inserted into the positioning recess140formed in the outer peripheral surface102of the stator core100. Thus, the first assembly200can be easily positioned on the stator core100.

In this embodiment, the positioning projection261and the positioning recess140constitute a positioning mechanism.

The positioning projection261is formed on the projection260that protrudes radially outward on the outer wall part210of the first assembly200, and the positioning recess140is formed on the outer peripheral surface of the stator core100. With this arrangement, the positioning projection261can be easily inserted into the positioning recess140, and the first assembly200can be easily assembled on the stator core100.

A plurality of positioning mechanisms may be provided. Furthermore, the positioning mechanism is not limited to a positioning mechanism that includes the positioning projection261and the positioning recess140.

In this embodiment, the cover500is mounted on the first assembly200via the mounting mechanisms at four positions (points) in the circumferential direction. In this embodiment, the first mounting mechanism (the first locking piece530, the first engagement recess240) is provided at each of three of the four positions, and the second mounting mechanism (the second locking piece550, the second engagement recess250) is provided at the other one position.

When mounting the cover500on the first assembly200, the cover500is placed on the first side of the first assembly200in the axial direction such that each locking piece (the first locking piece530, the second locking piece550) formed in the peripheral wall510of the cover500faces a corresponding engagement recess (the first engagement recess240, the second engagement recess250) formed in the outer wall part210of the first assembly200. Then, the cover500is moved toward the second side (the stator core100side) in the axial direction.

When the cover500is moved toward the second side in the axial direction, the claw531of the first locking piece530abuts on an outer peripheral surface of the outer wall part210and thereby the first locking piece530is elastically deformed radially outward. In this state, when the cover500is further moved until the claw531of the first locking piece530is moved to a position corresponding to the first engagement recess240, the abutment of the claw531of the first locking piece530on the outer peripheral surface of the outer wall part210is released and thereby the first locking piece530elastically returns radially inward. Thus, the locking surface531aof the claw531of the first locking piece530is engaged with the locking surface240aof the first engagement recess240. The inclined surface531bof the claw531facilitates radially outward deformation of the first locking piece530.

Furthermore, the claw551of the second locking piece550abuts on a wall surface of the insertion opening250A of the second engagement recess250and thereby the second locking piece550is elastically deformed radially inward. In this state, when the cover500is further moved until the claw551of the second locking piece550passes through the insertion opening250A, the abutment of the claw551of the second locking piece550on the wall surface of the insertion opening250A is released and the second locking piece550elastically returns radially outward. Thus, the locking surface551aof the claw551of the second locking piece550is engaged with the locking surface250aof the second engagement recess250. The inclined surface551bon the claw551facilitates radially inward elastic deformation of the second locking piece550.

In an embodiment in which the first mounting mechanism (the first locking piece530, the first engagement recess240) is used as the mounting mechanism for mounting the polymer cover500on the first assembly200and the cover500is formed (composed) of an electrically insulating polymer, as shown inFIGS.9to12, openings540through the top wall520of the cover500in the axial direction are formed (provided, defined) at positions of the top wall520, each of which corresponds to a respective one of the first locking pieces530.

In so-called eco-friendly cars such as hybrid vehicles (HV), electric vehicles (EV) and fuel cell vehicles (FCV), a compressor (which may be referred to as an “electric compressor”) having a compression mechanism part that is driven by a motor is used as the compressor for an air conditioner.

Recently, along with an increase in vehicle power supply voltage (400V or more, particularly 400 to 1500V), a motor designed for high voltage operation is also required to be used as the motor for an electric compressor of a vehicle.

In a motor designed for low voltage operation, an insulation distance between the stator winding(s)400arranged inside the first assembly200and an electrical component arranged outside of the outer wall part210of the first assembly200is adequate even if the openings540are formed in the top wall520of the cover500. However, in a motor designed for high voltage operation, the insulation distance may be reduced due to the presence of the openings540of the cover500.

In an embodiment in which the second mounting mechanism (the second locking piece550, the second engagement recess250) is used as the mounting mechanism(s) for mounting the cover500on the first assembly200and the cover500is formed (composed) of an electrically insulating polymer, unlike in the case of using the first mounting mechanism, an opening540is not formed at a position (portion) of the top wall530of the cover500corresponding to the second locking piece550. In other words, the position (portion) of the top wall530corresponding to the second locking piece550is imperforate.

In the motor of this embodiment, either the first mounting mechanism or the second mounting mechanism is selectively used according to the mounting position at which the cover500is mounted to (on) the first assembly200.

For example, at each of three of the four mounting positions in the circumferential direction, the first mounting mechanism (the first locking piece530, the first engagement recess240) is used to mount the cover500to (on) the first assembly200, and at the other one mounting position, the second mounting mechanism (the second locking piece550, the second engagement recess250) is used to mount the cover500to (on) the first assembly200.

In this case, at the position where the cover500is mounted on (to) the first assembly200by using the second mounting mechanism (the second locking piece550, the second engagement recess250), an opening through the top wall520is not formed at a position (portion) of the top wall520corresponding to the second locking piece550.

By using the second mounting mechanism, a reduction of the electrical insulation distance, which would otherwise be caused by the presence of the opening formed in the top wall520of the cover500, is avoided. For example, when an electrical component is arranged outside of the outer wall part210of the first assembly200in the vicinity of an arrangement position of the electrical component, the second mounting mechanism is used as the mounting mechanism for mounting the cover500to (on) the first assembly200.

Furthermore, the second lead parts400U2,400V2and400W2mounted on (fixed to) the outer wall part210of the first assembly200may come into contact with the winding parts and the first lead parts400U1,400V1and400W1.

In this embodiment, as shown inFIG.12, first, second and third wall parts521,522,523are formed (provided, defined) on the second side (the stator core100side) of the top wall520of the cover500in the axial direction. The first wall part521is formed radially inward of the peripheral wall510and extends in the circumferential direction and the axial direction. The second and third wall parts522,523are formed between ends of the first wall part521on the first and second sides in the circumferential direction and the peripheral wall510, and extend radially. The first, second and third wall parts521,522and523and the peripheral wall510define a recess (channel)524that extends in the circumferential direction and the axial direction and is open on the second side in the axial direction. The first, second and third wall parts521,522,523are configured such that the neutral point bus bar410and the projections211C,211D are located within the recess524when the cover500has been mounted on the first assembly200.

This arrangement increases the electrical insulation distance between the neutral point bus bar410and the winding parts and the first lead parts400U1,400V1and400W1.

In the above description, the cover500of the first embodiment, which includes the first locking pieces530and the second locking piece550both formed on the peripheral wall510and the openings540formed in the top wall520, is described, but covers having different configurations can also be used.

FIG.17shows a perspective view of a cover600of a second embodiment.

In the cover600, only the first mounting mechanisms are used as the mounting mechanisms for mounting the cover600to the first assembly200.

The cover600includes a peripheral (circumferential) wall610and a top wall620.

First locking pieces630each constituting a portion of a respective one of the first mounting mechanisms are formed (provided, defined) at four positions in the circumferential direction on the peripheral wall610, preferably equispaced.

First engagement recesses each constituting a portion of a respective one of the first mounting mechanisms are formed (provided, defined), at respective positions where the first locking pieces630are positioned, in the outer wall part210of the first assembly200.

Furthermore, openings640are formed (provided, defined), at positions corresponding to each of the first locking pieces630, in the top wall620such that the first locking piece630can be viewed through the opening640. Because the openings640through which the first locking pieces630can be viewed are provided, the first locking pieces630can be easily placed at positions facing the corresponding first engagement recesses.

The cover600of the second embodiment is used when a reduction of the electrical insulation distance due to the presence of the openings640formed in the top wall620of the cover600would not cause a problem.

FIG.18shows a perspective view of a cover700of a third embodiment.

In the cover700, only the second mounting mechanisms are used as the mounting mechanisms for mounting the cover700to the first assembly200.

The cover700includes a peripheral (circumferential) wall710and a top wall720.

Second locking pieces750each constituting a portion of a respective one of the second mounting mechanisms formed (provided, defined) at four positions in the circumferential direction on the peripheral wall710, preferably equispaced.

Second engagement recesses each constituting a portion of a respective one of the second mounting mechanisms are formed (provided, defined), at respective positions where the second locking pieces750are positioned, in the outer wall part210of the first assembly200.

Second engagement recesses each constituting a portion of a respective one of the second mounting mechanisms are formed (provided, defined) at respective positions where the second locking pieces750are positioned, in the outer wall part210of the first assembly200.

Furthermore, openings740are formed (provided, defined), at positions corresponding to the second locking pieces750, in the top wall720.

The cover700of the third embodiment is used when the electrical insulation distance relative to the stator winding400arranged in the first assembly200needs to be increased.

In the cover700of the third embodiment, an opening through the top wall720in the axial direction, which is formed when the cover700is formed of resin, is not formed (provided, defined).

The cover700shown inFIG.18is provided with openings740through the top wall720in the axial direction in the top wall720. The openings shown inFIG.18are provided in order to supply outside air to the stator winding arranged (disposed) inside the cover600. That is, outside air is supplied through the openings740to the stator winding arranged inside the cover700.

FIG.19shows a perspective view of a cover800of a fourth embodiment.

In the cover800, only the second mounting mechanisms are used as the mounting mechanisms for mounting the cover800to the first assembly200.

The cover800includes a peripheral (circumferential) wall810and a top wall820.

In this embodiment, no openings through the top wall810in the axial direction are formed (provided, defined) even when the cover800is formed (composed) of a polymer.

The motor described above can be modified, e.g., as follows.

Although the first and second movement restriction parts are formed in (on) the first assembly200, they may instead be formed in (on) the second assembly300. In such a modification, the crossover parts401a,410b,401cand the second lead parts400U2,400V2and400W2of the respective phases are arranged (disposed) on the second assembly300side.

Two second movement restriction parts are provided in the embodiments described above, one of which restricts movement of the second lead parts400U2,400V2and400W2toward the first side in the circumferential direction and the other restricts the movement toward the second side in the circumferential direction. However, only one second movement restriction part may be provided to restrict the movement toward one of the first and second sides in the circumferential direction.

In the above-described embodiments, the projection having an abutment part on which the neutral point bus bar410abuts is used as the second movement restriction part. However, the second movement restriction part is not limited to this design of the projection. In other words, the second movement restriction part may be configured to only restrict movement of the neutral point bus bar toward at least one of the first and second sides in the circumferential direction. In addition, the second movement restriction part may be omitted.

Although the first movement restriction part is formed by the two grooves (211a,211b) in the embodiments above, it may be formed by at least one groove.

Even though grooves (211a,211b) are used as a part of the first movement restriction part, the first movement restriction part is not limited to embodiments having such grooves. In other words, the first movement restriction part may be configured to only restrict the neutral point bus bar from moving radially inward and outward and toward the stator core side in the axial direction.

The grooves (211a,211b) that are open on the first and second sides in the circumferential direction are used as the first movement restriction part in the above embodiments. However, a groove that is open on one of the first and second sides in the circumferential direction or a groove that is closed on at least one of the first and second sides in the circumferential direction may instead be used as the first movement restriction part.

In the embodiments above, the neutral point part to which the second lead parts400U2,400V2and400W2are connected in common is formed by the neutral point bus bar410, but the structure of the neutral point part is not limited to this. For example, the neutral point part may be formed by one of the second lead parts to which the other two second lead parts are connected.

The structure of the cover is not limited to the structure described in the embodiments above. Furthermore, although the cover is mounted on the first assembly200, it may instead be mounted on the second assembly300. In such an embodiment, the crossover parts401a,401b,401cof the stator windings of respective phases are arranged (disposed) on the second assembly300side.

Further, the cover may be omitted.

The present disclosure can be provided with the following features.(Aspect 1) A motor, comprising a rotor and a stator, whereinthe stator includes a tubular stator core extending in an axial direction, first and second electrical insulator assemblies that are respectively arranged on a first and second sides of the stator core in the axial direction, and a stator winding;the stator core includes a yoke extending in a circumferential direction around an axis of the stator core and teeth each extending radially inward from the yoke;each of the first and second electrical insulator assemblies includes an outer wall part that extends in the circumferential direction and the axial direction, inner wall parts that are arranged radially inward of the outer wall part and that extend in the circumferential direction and the axial direction, and body parts that are arranged on the stator core side in the axial direction between the outer wall part and the inner wall parts and extend radially;the stator winding includes first, second and third phase stator windings, each of the stator windings including a winding part (coil) wound around a respective tooth of the stator core, a first lead part connected to a power supply, and a second lead part connected in common;wherein:the stator winding includes a neutral point part to which the second lead parts of the phase stator windings are connected in common; andthe outer wall part of the first electrical insulator assembly includes at least one first movement restriction part that restricts movement of the neutral point part.(Aspect 2) The motor as defined in Aspect 1, wherein the at least one first movement restriction part is configured to restrict the neutral point part from moving radially inward and radially outward and toward the second side in the axial direction.(Aspect 3) The motor as defined in Aspect 1 or 2, wherein:the outer wall part of the first electrical insulator assembly includes at least one first projection protruding toward the first side in the axial direction;the at least one first projection has a groove that extends in the circumferential direction and is open on the first side in the axial direction and is configured such that the neutral point part can be inserted therein; andthe at least one first movement restriction part includes the groove.(Aspect 4) The motor as defined in any one of Aspects 1 to 3, wherein the at least one first movement restriction part is configured to restrict movement of the neutral point part toward at least one of the first and second sides in the circumferential direction.(Aspect 5) The motor as defined in any one of Aspects 1 to 4, wherein the groove is closed on at least one of the first and second sides in the circumferential direction.(Aspect 6) The motor as defined in any one of Aspects 1 to 4, wherein the groove is open on one of the first and second sides in the circumferential direction.(Aspect 7) The motor as defined in any one of Aspects 1 to 3, wherein:the outer wall part of the first electrical insulator assembly includes at least one second movement restriction part on at least one of first and second sides of the at least one first movement restriction part in the circumferential direction; andthe at least one second movement restriction part is configured to restrict movement of the neutral point part toward the at least one of the first and second sides in the circumferential direction.(Aspect 8) The motor as defined in any one of Aspects 1 to 3, wherein the groove is open on first and second sides in the circumferential direction.(Aspect 9) The motor as defined in any one of Aspects 1 to 3 and 8, wherein:the outer wall part of the first electrical insulator assembly includes second movement restriction parts on each of first and second sides of the at least one first projection in the circumferential direction; andthe second movement restriction part arranged on the first side in the circumferential direction is configured to restrict movement of the neutral point part toward the first side in the circumferential direction, and the second movement restriction part arranged on the second side in the circumferential direction is configured to restrict movement of the neutral point part toward the second side in the circumferential direction.(Aspect 10) The motor as defined in Aspect 7 or 9, wherein the second movement restriction part includes at least one second projection protruding toward the first side in the axial direction.(Aspect 11) The motor as defined in any one of Aspects 8 to 10, wherein the neutral point part includes a neutral point bus bar to which the second lead parts of the phase stator windings are connected.(Aspect 12) The motor as defined in any one of Aspects 1 to 11, wherein:the stator includes a cover that is arranged on the first side of the first electrical insulator assembly in the axial direction;the cover includes a peripheral wall that is arranged outside of the outer wall part of the first electrical insulator assembly and a top wall that is arranged on the first side of the outer wall of the first electrical insulator assembly in the axial direction;the peripheral wall extends in the circumferential direction and the axial direction; andthe top wall is connected to an end of the peripheral wall on the first side in the axial direction and extends in a direction crossing the axial direction, and has an open part in a center.(Aspect 13) The motor as defined in Aspect 12, wherein mounting mechanisms are provided for mounting the cover to (on) the outer wall part of the first electrical insulator assembly and are respectively formed at positions spaced apart from each other in the circumferential direction.(Aspect 14) The motor as defined in Aspect 13, wherein:Each of the mounting mechanisms includes a locking piece formed in (on) the peripheral wall of the cover and an engagement recess formed in the outer wall part of the first electrical insulator assembly;the locking piece extends in the axial direction and is configured such that an end part on the second side in the axial direction can be elastically radially deformed relative to an end part on the first side in the axial direction, and the locking piece has a claw formed on the end part on the second side in the axial direction; andthe engagement recess is configured to be engageable (engaged) with (by) the claw of the locking piece.(Aspect 15) The motor as defined in Aspect 14, wherein:the claw formed on each of the locking pieces protrudes radially outward;the outer wall part of the first electrical insulator assembly includes a second projection that protrudes radially outward at a position where the locking piece is positioned on an end part of the outer wall part on the second side in the axial direction; andthe engagement recess is formed in the second projection.(Aspect 16) The motor as defined in Aspect 14, wherein:the claw formed on each of the locking pieces protrudes radially inward; andthe engagement recess is formed at a position where the locking piece is positioned on an end part of the outer wall part of the first electrical insulator assembly on the second side in the axial direction.(Aspect 17) The motor as defined in Aspect 14, wherein:the claw formed on at least one of the locking pieces protrudes radially outward,the claws formed on the locking pieces other than the at least one of the locking piece protrude radially inward,the outer wall part of the first electrical insulator assembly includes a second projection that protrudes radially outward at a position where the at least one of the locking piece is positioned on an end part of the outer wall part on the second side in the axial direction,the engagement recess that is configured to be engageable (engaged) with (by) the claw of the at least one of the locking piece is formed in the second projection; andat positions of the outer wall part of the first electrical insulator assembly where the other locking pieces rather than the at least one of the locking pieces are positioned, each of the engagement recesses is configured to be engageable (engaged) with (by) the other locking pieces rather than the at least one of the locking pieces are formed.(Aspect 18) A compressor, having a compression mechanism part for compressing a working medium and a motor for driving the compression mechanism part, wherein:the motor comprises the motor as defined in any one of Aspect 1 to 17.

The present disclosure is not limited to the structures described in the embodiment, but rather, may be added to, changed, replaced with alternatives or otherwise modified.

Embodiments of the present disclosure may be configured as a motor or a compressor.

Any of the features or structures described in the embodiment may be used individually or in combination of appropriately selected ones.

DESCRIPTION OF THE REFERENCE NUMERALS