Motor and compressor

Abstract

To provide a technique that, in a motor, improves the space factor of stator windings.SOLUTION: In a motor, a stator includes a stator core, an electrical insulation body, and stator windings. The stator core has a cylindrical shape extending in an axial direction. The stator core has a yoke extending in a circumferential direction, and multiple teeth extending radially inward from the yoke. Each of the teeth includes a tooth base part extending radially inward from the yoke, and a tooth tip part that is continuous with a radially inward tip end of the tooth base part. The electrical insulation body includes a first outer wall part disposed on a first side in the axial direction of the yoke, a first drum part disposed on the first side in the axial direction of the tooth base part, and a first inner wall part disposed on the first side in the axial direction of the tooth tip part. The first drum part includes a first side surface on the first side in the circumferential direction and a second side surface on the second side in the circumferential direction. The electrical insulation body includes a projection formed at a connection part between the first drum part and the first outer wall part, the projection having an inclined wall surface that is connected to an inner peripheral surface of the first outer wall part and the first side surface.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates to electric motors and compressors. [Background technology]

[0002] A concentrated winding stator is known in which the stator winding is wound around an electrical insulator that insulates the stator core from the stator winding. The stator has a yoke extending circumferentially, multiple teeth extending radially from the yoke, and multiple slots defined between adjacent teeth. The teeth have tooth bases extending radially inward from the yoke and tooth tips located at the tips of the tooth bases and extending circumferentially. For example, Patent Document 1 discloses a stator in which an inclined surface is formed on the upper surface of the tooth base. This allows the stator winding to be wound while sliding toward the outer wall portion along the inclined surface formed on the upper surface of the connecting portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-272045 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in conventional techniques, the stator windings are sometimes wound so as to cross each other, which can reduce the space factor of the stator windings in the slots. Therefore, there is a need to improve the space factor of the stator windings in the slots. [Means for solving the problem]

[0005] The present disclosure can be realized in the following forms.

[0006] (1) According to one aspect of the present disclosure, there is provided an electric motor including a stator and a rotor. In this electric motor, the stator includes a stator core, an electrical insulator, and a stator winding. The stator core has a cylindrical shape extending in the axial direction. The stator core has a yoke extending in the circumferential direction and a plurality of teeth extending radially inward from the yoke. The teeth include tooth bases extending radially inward from the yoke and tooth tip portions connected to radially inner tips of the tooth bases. The electrical insulator includes a first outer wall portion disposed on a first axial side of the yoke, a first body portion disposed on the first axial side of the tooth base, and a first inner wall portion disposed on the first axial side of the tooth tip portions. The first body portion has a first side surface on a first circumferential side and a second side surface on a second circumferential side. The stator winding is wound around the tooth base with the first body portion disposed at least on a first axial side of the tooth base. The electrical insulator includes a protrusion formed at a connection between the first body portion and the first outer wall portion, the protrusion having an inclined wall surface connected to an inner circumferential surface of the first outer wall portion and the first side surface. According to the electric motor of this aspect, it is possible to suppress or prevent the arrangement of the stator windings arranged on the first side surface from becoming disordered, and it is possible to improve the space factor of the stator windings. (2) In the electric motor of the above aspect, an inclination angle between a plane direction of the inclined wall surface and an extension direction of the first body portion may be equal to or greater than 40 degrees and equal to or less than 70 degrees. This type of motor encourages the stator windings to be arranged in a close-packed structure, thereby improving the space factor of the stator windings. (3) In the electric motor of the above aspect, the width of the inclined wall surface from the inner circumferential surface of the first outer wall portion to the first side surface may be 1.5 to 3 times the diameter of the conductor forming the stator winding. According to this form of motor, among the three stages of stator windings, the radially outermost stator windings are encouraged to be arranged in a closest-packed structure, thereby improving the space factor of the stator windings across multiple stages. (4) In the electric motor of the above aspect, a groove extending in the axial direction may be provided on the inner circumferential surface of the first outer wall portion at a position where the inner circumferential surface intersects with the surface direction of the second side surface. According to the electric motor of this aspect, it is possible to suppress or prevent interference between the stator winding led from the outer wall portion to the second side surface and the stator winding wound around the trunk portion. (5) In the electric motor of the above aspect, the first inner wall portion may further include a first flange portion protruding from the first body portion toward a first circumferential side and a second flange portion protruding from the first body portion toward a second circumferential side. The second flange portion may be configured to have a radial thickness greater than the radial thickness of the first flange portion. According to the electric motor of this aspect, it is possible to suppress or prevent gaps between the stator windings on the second side surface, and to improve the space factor of the stator windings. (6) In the electric motor of the above aspect, the position of the stator winding in contact with the second flange portion may be offset radially outward from the position of the stator winding in contact with the first flange portion. According to the electric motor of this configuration, the stator windings can be wound with an inclination radially outward relative to the circumferential direction, and it is possible to suppress or prevent the arrangement of the stator windings from becoming disordered. (7) In the electric motor of the above aspect, the radial thickness of the second flange portion may be thicker than the radial thickness of the first flange portion by a thickness that is 0.25 to less than 1.0 times the diameter of the conductor that forms the stator winding. According to the electric motor of this configuration, it is possible to suppress or prevent the occurrence of gaps between the stator windings on the second side surface and the stator windings from falling off. (8) In the electric motor of the above aspect, a groove extending in the axial direction may be provided on the inner circumferential surface of the first outer wall portion at a position where the inner circumferential surface intersects with the surface direction of the second side surface. According to the electric motor of this aspect, it is possible to suppress or prevent interference between the stator winding led from the outer wall portion to the second side surface and the stator winding wound around the trunk portion. (9) In the electric motor of the above aspect, the electrical insulator may further include a second outer wall portion disposed on a second axial side of the yoke, a second body portion disposed on a second axial side of the tooth bases, and a second inner wall portion disposed on a second axial side of the tooth tips. The electrical insulator may include a first electrical insulating portion including the first outer wall portion, the first body portion, and the first inner wall portion, and a second electrical insulating portion separate from the first electrical insulating portion and including the second outer wall portion, the second body portion, and the second inner wall portion. This type of electric motor allows for a simple method of producing the stator. Furthermore, because the first and second electrical insulating parts are separate, even if the axial length of the stator is changed, the electric motor can be manufactured without creating a new mold. (10) In the electric motor of the above form, the electrical insulator may further include a second protrusion formed at the connection between the second body portion and the second outer wall portion, and having a second inclined wall surface connected to the inner surface of the second outer wall portion and the second side surface. In this motor, the provision of inclined wall surfaces on both the first axial side and the second axial side facilitates axial arrangement of the stator windings, thereby more reliably suppressing or preventing the arrangement of the stator windings from becoming disordered. (11) In the electric motor of the above aspect, the electrical insulator may further include a second outer wall portion disposed on a second axial side of the yoke, a second body portion disposed on a second axial side of the tooth bases, and a second inner wall portion disposed on a second axial side of the tooth tips. The electrical insulator may include a first electrical insulating portion including the first outer wall portion, the first body portion, and the first inner wall portion, a second electrical insulating portion including the second outer wall portion, the second body portion, and the second inner wall portion, and an insulator connecting portion connected between the first electrical insulating portion and the second electrical insulating portion. This type of motor can reduce the number of steps required to assemble the electrical insulator and the stator core, thereby improving motor productivity. Furthermore, by positioning the insulator connection part at the axial center, even if the stack thickness (axial length) of the stator is changed, the motor can be manufactured without creating a new mold. (12) In the electric motor of the above form, the electrical insulator may further include a second protrusion formed at the connection between the second body portion and the second outer wall portion, and having a second inclined wall surface connected to the inner surface of the second outer wall portion and the second side surface. In this motor, the provision of inclined wall surfaces on both the first axial side and the second axial side facilitates axial arrangement of the stator windings, thereby more reliably suppressing or preventing the arrangement of the stator windings from becoming disordered. (13) According to another aspect of the present disclosure, there is provided a compressor including a compression mechanism that compresses and delivers a fluid and an electric motor that drives the compression mechanism. This compressor may include the electric motor according to any of the above aspects. The present disclosure can also be realized in various forms other than electric motors, such as a stator, a method for manufacturing a stator, a method for manufacturing an electric motor, a method for forming a stator winding, etc. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is an explanatory diagram showing the internal structure of a compressor including a motor according to the first embodiment. [Figure 2] FIG. 2 is an explanatory diagram showing the configuration of a stator used in the motor according to the first embodiment. [Figure 3] FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2. [Figure 4] FIG. 2 is a perspective view showing the external configuration of an electrical insulator. [Figure 5] FIG. 2 is a plan view showing the external configuration of the electrical insulator. [Figure 6] FIG. 6 is an explanatory diagram showing an enlarged view of a part of FIG. 5; [Figure 7] FIG. 2 is an explanatory diagram schematically showing a stator winding wound around a body portion. [Figure 8] FIG. [Figure 9] FIG. [Figure 10] FIG. 4 is an enlarged explanatory diagram showing the periphery of a protrusion. [Figure 11] FIG. 4 is an explanatory diagram showing an enlarged view of the first flange portion and the periphery of the second flange portion. [Figure 12] FIG. 4 is an explanatory diagram showing an enlarged view of a part of FIG. 3; [Figure 13] FIG. 10 is an explanatory diagram showing the configuration of a conventional stator core as a comparative example. [Figure 14] FIG. 10 is an explanatory diagram showing the configuration of a stator core included in a motor according to a second embodiment. [Figure 15] FIG. 10 is an explanatory diagram showing the configuration of a stator core included in a motor according to a third embodiment. [Figure 16] FIG. 10 is an explanatory diagram showing the configuration of a stator core included in a motor according to a fourth embodiment. [Figure 17] FIG. 10 is an explanatory diagram showing a modified example of the electrical insulator. DETAILED DESCRIPTION OF THE INVENTION

[0008] A. First embodiment: A1. Compressor 300 and motor 310 configuration: 1 is an explanatory diagram showing the internal structure of a compressor 300 including a motor 310 according to a first embodiment of the present disclosure. The compressor 300 is, for example, a scroll-type electric compressor. The compressor 300 is mounted, for example, on a vehicle (not shown) and functions as a refrigeration circuit of a vehicle air conditioner together with, for example, an evaporator, an expansion valve, and a condenser.

[0009] 1, compressor 300 includes housing 301, motor 310, compression mechanism 320 that compresses and discharges fluid, drive shaft 330, and drive circuit 340. Housing 301 accommodates motor 310 and compression mechanism 320. Housing 301 is formed with suction port 302, motor chamber 303 in which motor 310 is disposed, and discharge port 305.

[0010] The suction port 302 communicates with the motor chamber 303. The suction port 302 is connected to, for example, an evaporator (not shown), and receives refrigerant supplied from the evaporator and causes it to flow into the motor chamber 303. The discharge port 305 discharges the high-pressure refrigerant compressed by the compression mechanism 320 to the outside of the compressor 300. The discharge port 305 is connected to, for example, a condenser (not shown).

[0011] The drive shaft 330 is a substantially cylindrical member that extends along the rotation axis AX. The drive shaft 330 is supported within the housing 301 so as to be rotatable around the rotation axis AX. An eccentric pin 332 having a substantially cylindrical shape is formed on the end of the drive shaft 330. The eccentric pin 332 is positioned at a position offset a predetermined distance from the rotation axis AX.

[0012] The motor 310 generates a driving force that rotates the drive shaft 330 around the rotation axis AX. The motor 310 is an example of an "electric motor." The motor 310 has a stator 100 having a substantially cylindrical shape and a rotor 200. The stator 100 is fixed to a motor chamber 303. The stator 100 is electrically connected to a drive circuit 340. The drive circuit 340 is, for example, an inverter configured to control the motor 310. The rotor 200 is disposed inside the stator 100 so as to be rotatable relative to the stator 100. The rotor 200 is coupled to the drive shaft 330. The rotation of the rotor 200 causes the drive shaft 330 to rotate around the rotation axis AX.

[0013] The compression mechanism 320 includes a fixed scroll 322 and a movable scroll 324. The movable scroll 324 is connected to the drive shaft 330 via an eccentric pin 332. The fixed scroll 322 is fixed to the housing 301. A communication passage 304 is formed in the fixed scroll 322. The fixed scroll 322 and the movable scroll 324 each include a wall surface arranged in a spiral shape, and the spiral wall surfaces are arranged so as to mesh with each other. As a result, a compression chamber capable of compressing a refrigerant is formed between the fixed scroll 322 and the movable scroll 324. When the motor 310 is operated and the drive shaft 330 rotates around the rotation axis AX, the movable scroll 324 rotates, and the refrigerant in the compression chamber is compressed. The compressed refrigerant is discharged from the compression mechanism 320 through the communication passage 304 to the discharge port 305.

[0014] A2. Stator 100 configuration: FIG. 2 is an explanatory diagram showing the configuration of a stator 100 included in a motor 310 according to the first embodiment. As shown in FIG. 2, the stator 100 includes a stator core 80, an electrical insulator 70, and a stator winding 90. FIG. 2 schematically shows three directions used in the present disclosure. The "axial direction Z" refers to the axial direction of the rotation axis AX of the rotor 200. The side of the axial direction Z toward a first outer wall portion 72 (described later) is defined as the "axial first side Z1," and the opposite side is defined as the "axial second side Z2." When the motor 310 is disposed vertically, the axial first side Z1 may also be referred to as the "upper side," and the axial second side Z2 may also be referred to as the "lower side." The "circumferential direction X" refers to the circumferential direction centered on the rotation axis AX. In the circumferential direction X, when viewing the motor 310 from the first axial side Z1, the counterclockwise direction is defined as the "first circumferential side X1" and the clockwise direction is defined as the "second circumferential side X2." The "radial direction Y" is a direction that passes through the rotational axis AX and is perpendicular to the rotational axis AX. The radial direction Y refers to the radial direction centered on the rotational axis AX. In the radial direction Y, the side of the rotational axis AX is defined as the "radially inner side Y2," and the opposite side is defined as the "radially outer side Y1."

[0015] 3 is a cross-sectional view taken along the line III-III in FIG. 2. In FIG. 3, the stator winding 90 is omitted from the illustration in order to facilitate understanding of the technology. The stator core 80 is formed by laminating a plurality of electromagnetic steel sheets. As shown in FIG. 3, the stator core 80 has a yoke 82 extending along the circumferential direction X and a plurality of teeth 84. The electrical insulator 70 is configured to cover the stator core 80 in order to electrically insulate the stator winding 90 from the stator core 80.

[0016] The teeth 84 extend from the yoke 82 in a direction approaching the rotation axis AX, i.e., along the radially inward direction Y2. The teeth 84 are arranged so as to be spaced apart from one another along the circumferential direction X. The teeth 84 adjacent to one another in the circumferential direction define slots 78. The number of teeth 84 is set as appropriate.

[0017] Each of the teeth 84 includes a tooth base 846 and a tooth tip 844. The tooth base 846 is connected to a yoke inner circumferential surface 820 of the yoke 82. The tooth base 846 extends from the yoke inner circumferential surface 820 of the yoke 82 toward the radially inward direction Y2. The portion where the tooth base 846 and the yoke 82 are connected is also referred to as a "connection portion 863." The tooth base 846 includes a tooth first side surface 841 on a circumferential first side X1 and a tooth second side surface 842 on a circumferential second side X2.

[0018] The tooth tip portions 844 are portions connected to the tips of the tooth base portions 846 on the radially inner side Y2. As shown in Fig. 3, the tooth tip portions 844 extend from the tips of the tooth base portions 846 toward both the first circumferential side X1 and the second circumferential side X2. Teeth tip surfaces 844T formed on the radially inner side Y2 of the tooth tip portions 844 define a stator core inner space in which the rotor 200 is rotatably disposed.

[0019] 3, the slot 78 is a space defined by two teeth 84 adjacent to each other in the circumferential direction X and the yoke inner peripheral surface 820 of the stator core 80. The slot opening 780 is defined by the tooth tip portion 844 of the tooth 84 arranged on the first circumferential side X1 and the tooth tip portion 844 of the tooth 84 arranged on the second circumferential side X2. In the concentrated winding method, the stator winding 90 is wound around the body portion 74 by inserting a needle into the slot 78 from inside the electrical insulator 70 through the slot opening 780 and moving the inserted needle.

[0020] A3. Composition of electrical insulator 70: The configuration of the electrical insulator 70 will be described with reference to FIGS. 4 to 6. FIG. 4 is a perspective view showing the external configuration of the electrical insulator 70. FIG. 5 is a plan view showing the external configuration of the electrical insulator 70. The electrical insulator 70 is formed from a resin having insulating properties. The electrical insulator 70 is also sometimes called a "resin bobbin." As shown in FIG. 4, the electrical insulator 70 includes a first electrical insulating portion 701 disposed on the first axial side Z1 of the stator core 80, a second electrical insulating portion 702 disposed on the second axial side Z2 of the stator core 80, and an insulator connecting portion 703. Note that the electrical insulator 70 is not limited to being made of resin and may be made of a material other than resin.

[0021] The insulator connecting portion 703 is provided between the first electrical insulating portion 701 and the second electrical insulating portion 702. In this embodiment, as shown in Figures 3 and 4, the insulator connecting portion 703 is formed on the inner surface side of the stator core 80. Specifically, the insulator connecting portion 703 is formed on the yoke inner circumferential surface 820, the tooth first side surface 841, and the tooth second side surface 842.

[0022] In this embodiment, the electrical insulator 70 is formed by insert molding. Specifically, the electrical insulator 70 is formed by introducing a resin material into a mold with the stator core 80 disposed therein, and then hardening the resin material. As a result, the electrical insulator 70 is formed with the stator core 80 housed therein and with the first electrical insulating portion 701, the second electrical insulating portion 702, and the insulator connecting portion 703 integrated together.

[0023] The first electrical insulating portion 701 includes a first outer wall portion 72 arranged on the first axial side Z1 of the yoke 82, a first body portion 74 arranged on the first axial side Z1 of the tooth bases 846, and a first inner wall portion 76 arranged on the first axial side Z1 of the tooth tips 844. The second electrical insulating portion 702 includes a second outer wall portion arranged on the second axial side Z2 of the yoke 82, a second body portion arranged on the second axial side Z2 of the tooth bases 846, and a second inner wall portion arranged on the second axial side Z2 of the tooth tips 844. The second outer wall portion, the second body portion, and the second inner wall portion are formed at positions on the second axial side Z2 corresponding to the first outer wall portion 72, the first body portion 74, and the first inner wall portion 76, respectively. The second outer wall portion, the second body portion, and the second inner wall portion have the same configurations as the first outer wall portion 72, the first body portion 74, and the first inner wall portion 76, and therefore description thereof will be omitted. The insulator connecting portion 703 has a third outer wall portion arranged on the radially inner side Y2 of the yoke inner peripheral surface 820 of the yoke 82, a third body portion arranged on the first circumferential side X1 of the tooth bases 846, a fourth body portion arranged on the second circumferential side X2 of the tooth bases 846, a third inner wall portion arranged on the first circumferential side X1 of the tooth tip portions 844, and a fourth inner wall portion arranged on the second circumferential side X2 of the tooth tip portions 844. In this specification, when there is no distinction between the first outer wall portion 72, the second outer wall portion, and the third outer wall portion, they are simply referred to as the "outer wall portion 72," when there is no distinction between the first body portion 74, the second body portion, the third body portion, and the fourth body portion, they are simply referred to as the "body portion 74," and when there is no distinction between the first inner wall portion 76, the second inner wall portion, the third inner wall portion, and the fourth inner wall portion, they are simply referred to as the "inner wall portion 76."

[0024] 4, the outer wall portion 72 is a portion that extends further toward the first axial side Z1 than the trunk portion 74. Conductors that connect the stator windings 90 wound around the trunk portion 74 are arranged on the outer wall portion 72. Grooves 724, which will be described later, are formed on the outer wall portion 72.

[0025] The body portion 74 is a portion around which the stator winding 90 is wound. The portion where the body portion 74 and the outer wall portion 72 are connected is also referred to as a "connection portion 743." As shown in FIG. 5 , the body portion 74 has a first side surface 741 on a first circumferential side X1 and a second side surface 742 on a second circumferential side X2. The first side surface 741 is disposed on a first circumferential side of a tooth first side surface 841 of the stator core 80, and the second side surface 742 is disposed on a second circumferential side of a tooth second side surface 842. The first side surface 741 is included in a third body portion, and the second side surface 742 is included in a fourth body portion.

[0026] Fig. 6 is an explanatory diagram showing an enlarged view of a partial area AR2 in Fig. 5. In the electrical insulator 70, a protrusion 744 is formed on a connection portion 743 on the first side surface 741 side of a connection portion 743 where the body portion 74 and the outer wall portion 72 are connected. The protrusion 744 is configured to protrude from the inner circumferential surface 720 toward the radially inner side Y2 and from the first side surface 741 toward the circumferential first side X1. The protrusion 744 is formed over the entire length of the body portion 74 in the axial direction Z (see Fig. 4). In other words, in this embodiment, the electrical insulator 70 includes: a protrusion 744 formed at a connection 743 between the first body 74 and the first outer wall 72 in the first electrical insulating portion 701; a second protrusion having a second inclined wall surface formed at a connection 743 between the second body and the second outer wall in the second electrical insulating portion 702; and a third protrusion having a third inclined wall surface formed at a connection 743 between the third body and the third outer wall in the insulator connecting portion 703. By providing inclined wall surfaces on both the first axial side Z1 and the second axial side Z2 and across the space therebetween, the stator windings 90 are more easily arranged along the axial direction Z. This more reliably suppresses or prevents the arrangement of the stator windings 90 from becoming disarrayed. However, the protrusion 744 is not limited to extending over the entire length of the connection 743 of the body 74, and may be formed on only a portion of the connection 743. For example, the protrusion 744 may be formed only on the connection portion 743 between the first body portion 74 and the first outer wall portion 72. At least one of the second protrusion and the third protrusion may be omitted. Also, a plurality of protrusions 744 may be provided on one connection portion 743.

[0027] The protruding portion 744 has an inclined wall surface 744s that is connected to the inner circumferential surface 720 of the outer wall portion 72 and the first side surface 741. When the stator winding 90 is wound around the first side surface 741, the stator winding 90 that comes into contact with the protruding portion 744 can be guided along the inclined wall surface 744s to an appropriate arrangement position. Furthermore, the protruding portion 744 can restrict movement of the stator winding 90 toward the radially outer side Y1. The provision of the protruding portion 744 can suppress or prevent the stator windings 90 arranged around the body portion 74 from being wound in a manner that crosses each other.

[0028] When the surface of the trunk portion 74 on the first axial side Z1 is defined as a first end face 746, a plurality of protrusions 746E are formed on the first end face 746. The plurality of protrusions 746E are arranged along the extension direction of the trunk portion 74. The protrusions 746E protrude from the first end face 746 toward the first axial side Z1. More specifically, the protrusions 746E have a substantially triangular pyramid shape, with their apexes protruding from the first end face 746 toward the first axial side Z1. Adjacent protrusions 746E define recesses 746R. The recesses 746R restrict movement of the stator winding 90 arranged on the first end face 746 in the radial direction Y. The recesses 746R are arranged at equal intervals from one another. As a result, the stator windings 90 arranged on the first end face 746 are more likely to be arranged parallel to one another, and it is possible to suppress or prevent the stator windings 90 from being wound around the body portion 74 in a manner that crosses one another.

[0029] 6, the inner wall 76 is formed with a first flange 761 that protrudes from the trunk 74 toward a first circumferential side X1, and a second flange 762 that protrudes from the trunk 74 toward a second circumferential side X2. The first flange 761 and the second flange 762 prevent the stator winding 90 wound around the trunk 74 from falling off to the radially inner side Y2. In this embodiment, as will be described later, the second flange 762 is configured to have a thickness in the radial direction Y that is greater than the thickness in the radial direction Y of the first flange 761.

[0030] A4. Stator Winding 90 Configuration: FIG. 7 is an explanatory diagram schematically illustrating the stator winding 90 wound around the trunk portion 74. FIG. 7 schematically illustrates a distance L1 in the circumferential direction X from the wall surface of the first flange portion 761 on the radially outer side Y1 to the inner circumferential surface 720, and a distance L2 in the circumferential direction X from the wall surface of the second flange portion 762 on the radially outer side Y1 to the inner circumferential surface 720. FIG. 7 also schematically illustrates a thickness T1 in the radial direction Y of the first flange portion 761 and a thickness T2 in the radial direction Y of the second flange portion 762. Note that the configuration of each part is simplified in FIG. 7 to facilitate understanding of the technology. In this specification, for ease of explanation, the conductor forming the stator winding 90 may be simply referred to as the "stator winding 90."

[0031] A method for forming the stator winding 90 will be described. As shown in FIG. 4, the stator winding 90 is led from the outer wall portion 72 through the groove portion 724 to the trunk portion 74. The stator winding 90 led to the trunk portion 74 is repeatedly wound around the trunk portion 74 one turn at a time and arranged in order along the radial direction Y. The numbers in the stator winding 90 shown in FIG. 7 schematically indicate the order in which the stator winding 90 is wound. The numbers in the stator winding 90 are individually indicated for the first side surface 741 and the second side surface 742. In this embodiment, the winding order is from the second side surface 742 to the first side surface 741.

[0032] As indicated by the number "1" on the right side of Fig. 7, the stator winding 90 is led from the outer wall portion 72 to the vicinity of a connection portion 743 between the second side surface 742 and the inner circumferential surface 720. In this specification, the unit of arrangement of the stator winding 90 in the radial direction Y is defined as a "row," and the unit of arrangement in the circumferential direction X is defined as a "stage." In the example of Fig. 7, the outermost position in the radial direction Y in the first stage ST1 is the position of the stator winding 90 in the first row CL1, where the stator winding 90 is wound for the first time.

[0033] After passing over the second side surface 742 in the axial direction Z, the stator winding 90 passes through the second end surface of the body portion 74, which is the opposite side to the first end surface 746, from the second circumferential side X2 to the first circumferential side X1, as shown by arrow A1 in FIG. 7. As indicated by the number "1" on the left side of FIG. 7, the stator winding 90 that has passed through the second end surface is guided to the first side surface 741 and passes over the first side surface 741 in the axial direction Z. After passing over the first side surface 741, the stator winding 90 is guided over the first end surface 746 from the first circumferential side X1 to the second circumferential side X2, as shown by arrow A2 in FIG. 7. In this manner, one turn of the stator winding 90 is completed around the body portion 74.

[0034] The stator winding 90 is again guided to the second side surface 742, where it is wound repeatedly in the same manner. Specifically, as indicated by the number "2" on the right side of FIG. 7, the second and subsequent columns CL2 and CL3 are sequentially arranged adjacent to the first column CL1 toward the radially inward direction Y2. As indicated by the number "n+1" on the right side of FIG. 7, when the inner wall portion 76 is reached, the arrangement of the stator winding 90 in the first stage ST1 is completed. After the arrangement of the stator winding 90 in the first stage ST1 is completed, the stator winding 90 is stacked on the second circumferential side X2 relative to the first stage ST1, as indicated by the number "n+2" on the right side of FIG. 7. Note that, on the first side surface 741, the stator winding 90 is stacked on the first circumferential side X1 relative to the first stage ST1. The stator winding 90 begins to be arranged in the second stage ST2 toward the radially outward direction Y1, and the same process is repeated for the third and subsequent stages ST3 and ST4.

[0035] The configuration of the grooves 724 provided in the inner circumferential surface 720 of the outer wall portion 72 will be described using Figures 8 and 9. Figure 8 is an explanatory diagram showing the configuration of the outer wall portion 72. As shown in Figure 8, the grooves 724 are provided in the inner circumferential surface 720 of the outer wall portion 72 at positions where the planar direction SD of the second side surface 742 intersects and in the vicinity thereof. That is, the grooves 724 are formed on an extension of the second side surface 742 and in the vicinity thereof. Furthermore, the grooves 724 extend in the axial direction Z from the vicinity of the first end surface 746 of the trunk portion 74 on the inner circumferential surface 720 to the upper end 722T of the outer wall portion 72. In other words, the grooves 724 are provided on the introduction path of the stator winding 90 from the outer wall portion 72 to the trunk portion 74.

[0036] FIG. 9 is an explanatory diagram showing an enlarged view of the groove 724. As shown in FIG. 9, in this embodiment, the depth of the groove 724 is configured to approximately match the diameter of the conductor forming the stator winding 90. Therefore, the surface of the stator winding 90 passing through the groove 724 is approximately flush with the inner circumferential surface 720. In other words, by providing the groove 724 in the inner circumferential surface 720, the stator winding 90 can be shifted radially outward Y1 by the depth of the groove 724 in the introduction path of the stator winding 90 from the outer wall portion 72 to the second side surface 742. Therefore, for example, as shown at position P1 in FIG. 9, it is possible to suppress or prevent interference between a portion of the stator winding 90S introduced from the outer wall portion 72 to the second side surface 742 and a portion of the stator winding 90T constituting the second stage ST2 or any subsequent stage, as shown at position P2. The depth of groove 724 does not necessarily have to be approximately the same as the diameter of the conductor, but may be greater than the diameter of the conductor. The depth of groove 724 may also be smaller than the diameter of stator winding 90. Groove 724 may also be omitted.

[0037] Fig. 10 is an explanatory diagram showing an enlarged view of the periphery of the protruding portion 744. As shown in Fig. 10, if the stator windings 90 can be arranged in a close-packed structure in which the gaps between the stator windings 90 are substantially minimized, it is believed that the space factor of the stator windings 90 can be improved. When the inner circumferential surface of the protruding portion 744 is an inclined wall surface 744s, the outermost stator winding 90 in the radial direction Y can come into contact with the inclined wall surface 744s.

[0038] In this embodiment, the inclined wall surface 744s is a plane that inclines from the radially outer side Y1 to the radially inner side Y2 as it moves from the first circumferential side X1 to the second circumferential side X2. This configuration allows the arrangement of the stator windings 90, which are arranged at the outermost positions in the radial direction Y, in the first stage ST1, the second stage ST2, and the third stage ST3, to be regulated along the surface direction of the inclined wall surface 744s. Furthermore, in this embodiment, the inclination angle θ1 between the surface direction of the inclined wall surface 744s and the extension direction of the trunk portion 74 (the radial direction in this embodiment) is configured to be approximately 55 degrees. This configuration allows the stator windings 90 to be arranged in a close-packed structure, thereby improving the space factor of the stator windings 90. In this embodiment, when the inclination angle θ1 is set to 60 degrees, an error of 5 degrees is set, taking into account variations in the diameter of the stator windings 90 and variations in the arrangement positions of the stator windings 90. This prevents a decrease in the number of stator windings 90 arranged per stage due to variations in the diameter of the stator windings 90 or variations in the arrangement positions of the stator windings 90. However, the inclined wall surface 744s is not limited to being flat, and may be a curved surface. In this case, the inclined wall surface 744s may be a curved surface that is convex toward the radially inward direction, i.e., toward the slots 78, or a curved surface that is concave toward the radially outward direction, i.e., toward the side opposite the slots 78.

[0039] However, the inclination angle θ1 is not limited to 55 degrees. The inclination angle θ1 can be, for example, 60 degrees. Furthermore, the inclination angle θ1 is preferably 40 degrees or greater. If the inclination angle θ1 is less than 40 degrees, for example, the stator winding 90 arranged at the outermost position in the radial direction Y of the second stage ST2 may easily fall off toward the first stage ST1, which may result in a decrease in the space factor. Furthermore, the inclination angle θ1 is preferably 70 degrees or less. If the inclination angle θ1 is greater than 70 degrees, the space available for arranging the stator windings 90 in the radial direction Y may become smaller, which may reduce the number of stator windings 90 arranged per stage and result in a decrease in the space factor.

[0040] 10 shows the cross-sectional width WS of the inclined wall surface 744s. Here, the cross-sectional width WS of the inclined wall surface 744s refers to the width from the inner circumferential surface 720 of the outer wall portion 72 to the first side surface 741. In this embodiment, the cross-sectional width WS is configured to be approximately 2.2 times the diameter DM of the conductor forming the stator winding 90. With this configuration, in the three stages from the first stage ST1 to the third stage ST3, the outermost stator winding 90 in the radial direction Y can be arranged to have a close-packed structure, thereby improving the space factor of the stator winding 90 across multiple stages.

[0041] However, the cross-sectional width WS is not limited to 2.2 times the diameter DM. The cross-sectional width WS is preferably, for example, 1.5 times the diameter DM or more. This configuration allows the outermost stator windings 90 in the radial direction Y to be arranged in a close-packed structure in at least two stages, the first stage ST1 and the second stage ST2. If the cross-sectional width WS is less than 1.5 times the diameter DM, it may be difficult to align the stator windings 90 in the second stage ST2 and subsequent stages. Furthermore, the cross-sectional width WS is preferably, for example, 3 times the diameter DM or less. If the cross-sectional width WS is more than 3 times the diameter DM, the size of the protrusion 744 may be excessive. For example, the number of rows of the stator windings 90 that can be arranged in the first stage ST1 may be reduced, resulting in a lower space factor.

[0042] 10 shows the thickness WT of the protrusion 744 in the radial direction Y. In this embodiment, the thickness WT is determined in accordance with the design of the cross-sectional width WS and the inclination angle θ1. However, the thickness WT may also be set using the distance from the protrusion 744 to the first flange 761 in the radial direction Y. For example, by setting the thickness WT so that the distance from the protrusion 744 to the first flange 761 in the radial direction Y is an integer multiple of the diameter DM, it is possible to suppress or prevent gaps from occurring between the stator windings 90 arranged on the first side surface 741.

[0043] The configuration of the inner wall portion 76 will be described with reference to FIG. 11. FIG. 11 is an explanatory diagram showing an enlarged view of the periphery of the first flange portion 761 and the second flange portion 762. As shown in FIG. 11, in this embodiment, the thickness T2 of the second flange portion 762 in the radial direction Y is configured to be thicker than the thickness T1 of the first flange portion 761 in the radial direction Y. More specifically, the thickness T2 of the second flange portion 762 at the radially outer side Y1 is configured to be thicker than the thickness T1 of the first flange portion 761 by a thickness TU. By increasing the thickness T2 of the second flange portion 762, the position of the stator winding 90 arranged on the second side surface 742 can be offset toward the radially outer side Y1 by the increased thickness TU. Note that the product of the distance L1 and the thickness T1 shown in FIG. 7 is substantially the same as the product of the distance L2 and the thickness T2. The distance from the inner wall portion 76 to the rotor 200 is approximately uniform from the first flange portion 761 to the second flange portion 762. In addition, the distance from the inner circumferential surface 720 to the tip end surface of the inner wall portion 76 is approximately constant.

[0044] FIG. 11 shows, as a comparative example, a position 90R of the stator winding 90 when the thickness of the second flange 762 is not increased. A gap SP may occur between the stator winding 90 arranged at the arrangement position 90R and the stator winding 90 arranged at the adjacent position 90Q. If a gap SP occurs, the stator winding 90 in the second stage ST2 may fall off, which may reduce the space factor. In this embodiment, the thickness TU is set to a thickness equivalent to the gap SP, thereby suppressing or preventing the occurrence of the gap SP. By configuring the stator winding 90 so that it can be arranged in a close-packed structure even at the innermost position in the radial direction Y, the space factor of the stator winding 90 can be improved.

[0045] Note that the thickness TU may be set using the remainder (also referred to as the "remainder") obtained when dividing the distance L2 in the circumferential direction X from the wall surface on the radially outer side Y1 of the second flange portion 762 to the inner circumferential surface 720 shown in Fig. 7 by the diameter DM. In other words, the thickness TU can be determined by a simple method in which the calculated remainder is predicted to be the size of the gap SP.

[0046] The thickness TU may be set using the diameter DM of the conductor forming the stator winding 90. For example, the thickness TU may be set to 0.5 times the diameter DM of the conductor forming the stator winding 90. This configuration can suppress or prevent gaps between the stator windings 90 on the second side surface 742 and the stator windings 90 from falling off into the first stage ST1. The thickness TU is preferably set to, for example, 0.25 times the diameter DM or more. If the thickness TU is less than 0.25 times the diameter DM, gaps may occur between the stator windings 90, potentially disrupting the arrangement of the stator windings 90. Furthermore, the thickness TU is preferably set to less than 1.0 times the diameter DM. If the thickness TU is 1.0 times the diameter DM or more, the number of stator windings 90 that can be arranged on the second side surface 742 may be reduced.

[0047] 11 , the second flange 762 extends from a second side surface 742, which is the side surface of the body portion 74 opposite to the first side surface 741 on which the protruding portion 744 is formed. In other words, the thickness of the flange on the side opposite to the protruding portion 744 across the body portion 74 in the circumferential direction X is increased. By increasing the thickness T2 of the second flange 762 on the side opposite to the protruding portion 744, the relative position of the stator windings 90 arranged on the second side surface 742 can be offset from the position of the stator windings 90 arranged on the first side surface 741 in accordance with the size of the protruding portion 744.

[0048] In this embodiment, the position of the stator winding 90 on the second side surface 742 is offset radially outward Y1 relative to the position of the stator winding 90 on the parallel first side surface 741. In the example of Fig. 11, the position of the stator winding 90A that contacts the second flange 762 on the second side surface 742 side is offset radially outward Y1 by an angle θ2 relative to the position of the stator winding 90B that contacts the first flange 761 on the first side surface 741 side. Note that when the stator winding 90 on the second side surface 742 is arranged in parallel with the stator winding 90 on the first side surface 741 along the circumferential direction X, as in arrangement position 90R, the angle θ2 is zero.

[0049] In this embodiment, by winding the stator winding 90 at an angle θ2 toward the radially outward side Y1 with respect to the parallel arrangement, it is possible to wind the stator winding 90 while applying a force in a direction toward the radially outward side Y1. Therefore, the next stator winding 90 can be wound adjacent to the stator winding 90 already wound on the radially outward side Y1, which can suppress or prevent the arrangement of the stator windings 90 from being disturbed. Note that, as shown in FIG. 6, the arrangement of the recesses 746R on the second side face 742 side is offset by the angle θ2 from the arrangement of the recesses 746R on the first side face 741 side.

[0050] A5. Stator Core 80 Configuration: The configuration of the stator core 80 will be described with reference to Figures 12 and 13. Figure 12 is an explanatory diagram showing an enlarged view of a partial area AR1 of Figure 3. In this embodiment, as shown in Figure 12, a notch 86 having a recessed shape facing in the direction opposite to the direction toward the slot 78 is formed in a connection portion 863 of the stator core 80 where the tooth second side surface 842 and the yoke inner peripheral surface 820 are connected.

[0051] FIG. 13 is an explanatory diagram showing the configuration of a conventional stator core 80R as a comparative example. As shown in FIG. 13, the conventional electrical insulator 70R does not have a protrusion 744, and the stator core 80R does not have a notch 86. In the conventional stator core 80R, the cross-sectional area of the connection portion 743 on the first side surface 741 side is substantially the same as the cross-sectional area of the connection portion 743 on the second side surface 742 side. Therefore, when forming the electrical insulator 70R using the stator core 80R, the flow rate of the resin material at the connection portion 743 on the first side surface 741 side is substantially the same as the flow rate of the resin material at the connection portion 743 on the second side surface 742 side. For example, when forming the electrical insulator 70 by insert molding, when the resin material is introduced between the stator core 80 and the mold, the resin material tends to flow substantially uniformly on the first side surface 741 side and the second side surface 742 side.

[0052] In contrast to this, in this embodiment, as shown in Fig. 12, a protrusion 744 is formed at a connection portion 743 on the first side surface 741 side of the electrical insulator 70. Area S1, shown by cross-hatching in Fig. 12, is the cross-sectional area of the protrusion 744. Area S1 can be considered to be the area increased by the formation of the protrusion 744 compared to the conventional electrical insulator 70R.

[0053] For example, if the notch 86 shown in FIG. 12 is not formed and only the protruding portion 744 is formed, the volume of the space between the mold and the stator core 80 increases by an amount corresponding to the area S1. Therefore, when the electrical insulator 70 is formed by insert molding, the resin tends to flow into the position of the protruding portion 744. As a result, the flow rate of the resin material on the first side surface 741 side may be greater than the flow rate of the resin material on the second side surface 742 side. In this case, the resin material may not be sufficiently filled between the connecting portion 743 on the second side surface 742 side and the mold, which may result in molding defects such as a so-called short shot.

[0054] In this embodiment, a notch 86 is formed in a tooth second side surface 842 opposite to the tooth first side surface 841 on which the protrusion 744 is formed. The notch 86 increases the volume from the stator core 80 to the mold, improving the flow rate of the resin material introduced during insert molding. In this embodiment, by forming the notch 86 on the second side surface 742 side, the flow rate of the resin material in the connection portion 743 on the first side surface 741 side and the flow rate of the resin material in the connection portion 743 on the second side surface 742 side are configured to be approximately uniform.

[0055] As shown in FIG. 12 , the notch 86 is formed in the yoke inner circumferential surface 820 of the yoke 82. The notch 86 has a first portion 86P1 having a recessed shape extending from the yoke inner circumferential surface 820 toward the radially outward direction Y1, and a second portion 86P2 having a recessed shape extending from the tooth second side surface 842 toward the circumferential first side X1. By including both the first portion 86P1 and the second portion 86P2, the area of the notch 86 is increased, thereby improving the flow rate of resin material through the notch 86. In this embodiment, the first portion 86P1 and the second portion 86P2 are connected to each other and form an integrated recessed shape. By forming the notch 86 over a wide range from the yoke inner circumferential surface 820 to the tooth second side surface 842, the flow rate of resin material through the connection portion 863 can be increased compared to when the notch 86 is provided separately on the yoke inner circumferential surface 820 and the tooth second side surface 842.

[0056] As shown in FIG. 12, the planar shape of the notch 86 is formed using curves. For example, the first portion 86P1 and the second portion 86P2 are connected by a curved portion 862 with a small curvature. The curvature of the curved portion 862 is smaller than the curvature of a connection portion 863 between the yoke inner circumferential surface 820 and the tooth first side surface 841, for example, shown on the left side of FIG. 12. This configuration reduces the flow resistance of the notch 86 and improves the flow rate of the resin material through the notch 86 during insert molding. Therefore, the notch 86 can be made smaller than if the curved portion 862 were not provided.

[0057] In the present embodiment, the cross-sectional area S1 of the protruding portion 744 and the cross-sectional area S2 of the cutout portion 86 are configured to be different from each other. Specifically, the cross-sectional area S2 is configured to be smaller than the cross-sectional area S1. This is because the difference in the flow rate of the resin material between the first side surface 741 side and the second side surface 742 side is taken into consideration, as the thickness T2 of the second flange portion 762 is configured to be thicker than the thickness T1 of the first flange portion 761.

[0058] As described above, according to the motor 310 of this embodiment, the electrical insulator 70 includes a protrusion 744 connected to the inner circumferential surface 720 of the outer wall portion 72 and the first side surface 741 at a connection portion 743 between the body portion 74 and the outer wall portion 72. When the stator winding 90 is wound around the first side surface 741, the stator winding 90 can be guided along the protrusion 744 to an appropriate arrangement position. Furthermore, the protrusion 744 can restrict movement of the stator winding 90 toward the radially outward side Y1. Therefore, it is possible to suppress or prevent the arrangement of the stator winding 90 arranged on the first side surface 741 from becoming disordered, and the space factor of the stator winding 90 can be improved.

[0059] According to the motor 310 of this embodiment, the inclination angle θ1 between the surface direction of the inclined wall surface 744s and the extension direction of the trunk portion 74 is configured to be approximately 55 degrees. By configuring in this manner, the stator windings 90 can be densely arranged to form a close-packed structure, and the space factor of the stator windings 90 can be improved.

[0060] According to the motor 310 of this embodiment, the cross-sectional width WS of the protruding portion 744 from the inner circumferential surface 720 to the first side surface 741 is configured to be approximately 2.2 times the diameter DM of the conductor forming the stator winding 90. With this configuration, the outermost stator windings 90 in the radial direction Y can be densely arranged to form a close-packed structure in three stages from the first stage ST1 to the third stage ST3. Therefore, the space factor of the stator windings 90 across multiple stages can be improved.

[0061] According to the motor 310 of the present embodiment, the thickness T2 of the second flange 762 in the radial direction Y is configured to be greater than the thickness T1 of the first flange 761 in the radial direction Y. Therefore, it is possible to suppress or prevent the generation of gaps SP between the stator windings 90 on the second side surface 742, and it is possible to improve the space factor of the stator windings 90.

[0062] According to the motor 310 of this embodiment, the position of the stator winding 90A that contacts the second flange 762 on the second side surface 742 is offset by an angle θ2 toward the radially outward direction Y1 from the position of the stator winding 90B that contacts the first flange 761 on the first side surface 741. By winding the stator winding 90 at an angle θ2 toward the radially outward direction Y1 with respect to the parallel arrangement, the stator winding 90 can be wound while applying a force in a direction toward the radially outward direction Y1. Therefore, the next stator winding 90 can be wound adjacent to the stator winding 90 already wound on the radially outward direction Y1, which can suppress or prevent the arrangement of the stator windings 90 from being disrupted.

[0063] The motor 310 of this embodiment has a groove 724 extending in the axial direction at a position on the inner circumferential surface 720 where the groove 724 intersects with the planar direction SD of the second side surface 742. This makes it possible to suppress or prevent interference between the stator winding 90S guided from the outer wall portion 72 to the second side surface 742 and the stator winding 90T constituting the second stage ST2 or any subsequent stages.

[0064] According to the motor 310 of this embodiment, the first electrical insulating portion 701, the second electrical insulating portion 702, and the insulator connecting portion 703 of the electrical insulator 70 are integrally formed by insert molding. This reduces the number of steps required to assemble the electrical insulator 70 and the stator core 80, thereby improving the productivity of the motor 310.

[0065] According to the motor 310 of this embodiment, the stator core 80 includes recessed notches 86 formed in the tooth second side surface 842 and the yoke inner circumferential surface 820 of the yoke 82 adjacent to the tooth second side surface 842. Therefore, when the electrical insulator 70 is formed by insert molding, the flow rate of the resin material at the connection portion 743 on the second side surface 742 side can be improved. Therefore, even if the flow rate of the resin material at the connection portion 743 on the first side surface 741 side is increased to form the protrusion 744, for example, the flow rate of the resin material between the first side surface 741 side and the second side surface 742 side can be favorably balanced. Therefore, molding defects such as short shots can be reduced or prevented when forming the electrical insulator 70.

[0066] According to motor 310 of this embodiment, notch 86 has an integral recessed shape that includes a first portion 86P1 formed on yoke inner circumferential surface 820 of yoke 82 and a second portion 86P2 formed on tooth second side surface 842 at connection portion 863 where tooth base 846 and yoke 82 are connected. By forming notch 86 widely from yoke inner circumferential surface 820 to tooth second side surface 842, the flow rate of resin material at notch 86 during insert molding can be increased compared to when notch 86 is provided separately on yoke inner circumferential surface 820 and tooth second side surface 842.

[0067] According to the motor 310 of this embodiment, the notch 86 has a curved portion 862 with a curvature smaller than the curvature of a connection portion 863 between the yoke inner circumferential surface 820 of the yoke 82 and the tooth first side surface 841. This reduces the flow resistance of the notch 86 and improves the flow rate of the resin material in the notch 86 during insert molding.

[0068] According to motor 310 of this embodiment, cross-sectional area S1 of protrusion 744 is different from cross-sectional area S2 of cutout 86. Even if there is a difference in the flow rate of resin material at a position other than connecting portion 863, such as a difference in thickness between second flange 762 and first flange 761, it is possible to suitably set the balance of the flow rate of resin material during insert molding.

[0069] B. Second embodiment: 14 is an explanatory diagram showing the configuration of a stator core 80b included in a motor 310 according to the second embodiment. Stator core 80b differs from stator core 80 shown in the first embodiment in that it has tooth protrusions 88 instead of cutouts 86, but the configuration is otherwise similar. When forming electrical insulator 70 having protrusions 744 by insert molding, tooth protrusions 88 suppress or prevent an increase in the flow rate of resin material flowing through connection portions 743 on the first side surface 741 side.

[0070] The tooth protrusions 88 are connected to the yoke inner circumferential surface 820 of the yoke 82 and the tooth first side surface 841 at the connection portion 863 between the tooth bases 846 and the yoke 82. The tooth protrusions 88 have a shape that protrudes toward the slots 78. In this embodiment, the shape of the tooth protrusions 88 is substantially the same as the cross-sectional shape of the protrusions 744 shown in the first embodiment. Specifically, the tooth protrusions 88 are configured to protrude from the yoke inner circumferential surface 820 toward the radially inward direction Y2 and from the tooth first side surface 841 toward the circumferentially first side X1. The tooth protrusions 88 have tooth inclined wall surfaces 88s that are connected to the yoke inner circumferential surface 820 and the tooth first side surface 841. The inclination angle θ3 between the surface direction of the tooth inclined wall surfaces 88s of the tooth protrusions 88 and the radial direction Y is configured to be approximately 55 degrees, the same as the inclination angle θ1. Forming tooth protrusions 88 can suppress an increase in the volume between connecting portion 863 and the mold. Therefore, when forming protrusions 744, an increase in the flow rate of resin material on first side surface 741 can be suppressed or prevented.

[0071] In this embodiment, the distance TB from the tooth inclined wall surface 88s to the mold is set to be the same as, for example, the distance TA1 from the yoke inner circumferential surface 820 on the side of the tooth first side surface 841 to the mold, the distance TA2 from the tooth first side surface 841 to the mold, the distance TA4 from the yoke inner circumferential surface 820 on the side of the tooth second side surface 842 to the mold, and the distance TA3 from the tooth second side surface 842 to the mold. "The same as the distance TB" means that the distance TB includes an error of plus or minus 10%. This allows, for example, the flow rate of the resin material during insert molding to be uniform throughout. Therefore, while forming the protrusion 744, local variations in the flow rate of the resin material during insert molding can be suppressed or prevented. Furthermore, uniforming the thickness of the electrical insulator 70 can suppress or prevent local variations in the insulation performance of the stator core 80.

[0072] C. Third embodiment: FIG. 15 is an explanatory diagram showing the configuration of a stator core 80c included in a motor 310 according to the third embodiment. As shown in FIG. 15, the stator core 80c includes notches 86c that are smaller versions of the notches 86 described in the first embodiment, and tooth protrusions 88c that are smaller versions of the tooth protrusions 88 described in the second embodiment. In this manner, the stator core 80c may include both the notches 86c and the tooth protrusions 88c. Even with this configuration, when forming the electrical insulator 70 having the protrusions 744 by insert molding, the flow rate of the resin material during insert molding can be suitably balanced between the first side surface 741 and the second side surface 742.

[0073] D. Fourth embodiment: FIG. 16 is an explanatory diagram showing the configuration of a stator core 80d included in a motor 310 according to the fourth embodiment. As shown in FIG. 16, the stator core 80d includes multiple cutouts 86d1 and 86d2. More specifically, the stator core 80d differs from the stator core 80 shown in the first embodiment in that it does not include a curved portion 862 and that a first portion 86P1 formed on the yoke inner circumferential surface 820 of the yoke 82 and a second portion 86P2 formed on the tooth second side surface 842 are separate bodies. As a result, the first portion 86P1 functions as the cutout 86d1, and the second portion 86P2 functions as the cutout 86d2. Even with this configuration, when forming the electrical insulator 70 having the protrusion 744 by insert molding, the flow rate of the resin material during insert molding can be suitably balanced between the first side surface 741 and the second side surface 742.

[0074] E. Other Embodiments: (E1) FIG. 17 is an explanatory diagram showing a modified example of the electrical insulator. In the above embodiment, an example was shown in which the electrical insulator 70 was formed by insert molding. However, the electrical insulator 70 may be formed by a method other than insert molding. For example, the first electrical insulating portion 701 and the second electrical insulating portion 702 may be configured to be separate bodies by being individually molded. In this case, the insulator connecting portion 703 is not provided, and the first electrical insulating portion 701 and the second electrical insulating portion 702 are each assembled to the stator core 80. This allows the stator 100 to be produced by a simple method. Furthermore, by forming the first electrical insulating portion 701 and the second electrical insulating portion 702 as separate bodies, the motor 310 can be manufactured without creating a new molding die even if the length of the stator 100 in the axial direction Z is changed. 17 , insulation between the stator winding 90 and the teeth 84 is achieved by, for example, an insulating film IF arranged between the stator winding 90 and the teeth 84, instead of the insulator connection portion 703. The second electrical insulating portion 702 may include a second protruding portion formed at a connection portion 743 between the second body portion and the second outer wall portion, and having a second inclined wall surface connected to the inner circumferential surface and the second side surface of the second outer wall portion. Furthermore, for example, if a sufficient space factor can be obtained by providing the protruding portion 744 provided on the first electrical insulating portion 701, the second protruding portion may be omitted.

[0075] The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit thereof. For example, the technical features in the embodiments corresponding to the technical features in each aspect described in the Summary of the Invention section can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted. [Explanation of symbols]

[0076] 70, 70R...electrical insulator, 72...outer wall portion, 74...body portion, 76...inner wall portion, 78...slot, 80, 80R, 80b, 80c, 80d...stator core, 82...yoke, 84...teeth, 86, 86c, 86d1, 86d2...notch portion, 86P1...first portion, 86P2...second portion, 88, 88c...teeth protrusion portion, 88s...teeth inclined wall surface, 90, 90A, 90B, 90S, 90T...stator winding, 100...stator, 200...rotor, 300...compressor, 301...housing, 302...suction port, 303...motor chamber, 304...communicating passage, 305...discharge port, 310...motor, 320...compression mechanism, 322...fixed scroll, 324...moving scroll, 330...drive Driving shaft, 332... eccentric pin, 340... drive circuit, 701... first electrical insulating portion, 702... second electrical insulating portion, 703... insulator connecting portion, 720... inner circumferential surface, 722T... upper end, 724... groove portion, 741... first side surface, 742... second side surface, 743... connecting portion, 744... protruding portion, 744s... inclined wall surface, 746... first end surface, 746E... protruding portion, 746R ...recess, 761...first flange, 762...second flange, 780...slot opening, 820...yoke inner surface, 841...teeth first side surface, 842...teeth second side surface, 844...teeth tip, 844T...teeth tip surface, 846...teeth base, 862...curved portion, 863...connection portion, AX...rotating axis, IF...insulating film, SP...gap

Claims

1. An electric motor comprising a stator and a rotor, the stator includes a stator core, electrical insulators, and a stator winding; The stator core is It has a cylindrical shape extending in the axial direction, a yoke extending in a circumferential direction and a plurality of teeth extending radially inward from the yoke; The teeth are a teeth base extending radially inward from the yoke; a tooth tip portion connected to a radially inner tip of the tooth base portion, The electrical insulator is a first outer wall portion disposed on a first axial side of the yoke; a first body portion disposed on a first axial side of the tooth base; a first inner wall portion disposed on a first axial side of the tip end portion of the teeth, the first barrel portion has a first side surface on a first side in the circumferential direction and a second side surface on a second side in the circumferential direction, the stator winding is wound around the tooth base with the first body portion disposed at least on a first axial side of the tooth base, the electrical insulator includes a protrusion formed at a connection portion between the first body portion and the first outer wall portion, the protrusion having an inclined wall surface connected to an inner circumferential surface of the first outer wall portion and the first side surface; Electric motor.

2. 2. The electric motor according to claim 1, The inclination angle between the surface direction of the inclined wall surface and the extension direction of the first body portion is 40 degrees or more and 70 degrees or less. Electric motor.

3. 2. The electric motor according to claim 1, a width of the inclined wall surface from an inner circumferential surface of the first outer wall portion to the first side surface is 1.5 to 3 times the diameter of a conductor forming the stator winding; Electric motor.

4. 2. The electric motor according to claim 1, A groove portion extending in the axial direction is provided on an inner circumferential surface of the first outer wall portion at a position where the groove portion intersects with a surface direction of the second side surface. Electric motor.

5. 2. The electric motor according to claim 1, the first inner wall portion further includes a first flange portion protruding from the first body portion toward a first side in the circumferential direction, and a second flange portion protruding from the first body portion toward a second side in the circumferential direction, The second flange portion has a radial thickness greater than the radial thickness of the first flange portion. Electric motor.

6. 6. The electric motor according to claim 5, a position of the stator winding in contact with the second flange portion is offset radially outward from a position of the stator winding in contact with the first flange portion; Electric motor.

7. 6. The electric motor according to claim 5, the radial thickness of the second flange portion is greater than the radial thickness of the first flange portion by a thickness that is 0.25 to less than 1.0 times the diameter of a conductor that forms the stator winding; Electric motor.

8. 6. The electric motor according to claim 5, A groove portion extending in the axial direction is provided on an inner circumferential surface of the first outer wall portion at a position where the groove portion intersects with a surface direction of the second side surface. Electric motor.

9. 2. The electric motor according to claim 1, The electrical insulator is the rotor further includes a second outer wall portion disposed on a second axial side of the yoke, a second body portion disposed on a second axial side of the tooth base, and a second inner wall portion disposed on a second axial side of the tooth tip, a first electrically insulating portion including the first outer wall portion, the first body portion, and the first inner wall portion; and a second electrically insulating portion that is separate from the first electrically insulating portion and includes the second outer wall portion, the second body portion, and the second inner wall portion. Electric motor.

10. 10. The electric motor according to claim 9, The electrical insulator further includes a second protrusion formed at a connection between the second body portion and the second outer wall portion, the second protrusion having a second inclined wall surface connected to an inner circumferential surface of the second outer wall portion and the second side surface. Electric motor.

11. 2. The electric motor according to claim 1, The electrical insulator is the rotor further includes a second outer wall portion disposed on a second axial side of the yoke, a second body portion disposed on a second axial side of the tooth base, and a second inner wall portion disposed on a second axial side of the tooth tip, a first electrical insulating portion including the first outer wall portion, the first body portion, and the first inner wall portion; a second electrical insulating portion including the second outer wall portion, the second body portion, and the second inner wall portion; and an insulator connecting portion provided between the first electrical insulating portion and the second electrical insulating portion, Electric motor.

12. 12. The electric motor according to claim 11, The electrical insulator further includes a second protrusion formed at a connection between the second body portion and the second outer wall portion, the second protrusion having a second inclined wall surface connected to an inner circumferential surface of the second outer wall portion and the second side surface. Electric motor.

13. A compressor including a compression mechanism that compresses and discharges a fluid and an electric motor that drives the compression mechanism, The electric motor is the electric motor according to any one of claims 1 to 12. Compressor.

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