WO2015119214A1

WO2015119214A1 - Stator assembly

Info

Publication number: WO2015119214A1
Application number: PCT/JP2015/053293
Authority: WO
Inventors: 孝行中田; 森田　司; 田口　直人; 吉留　正朗
Original assignee: 日産自動車株式会社
Priority date: 2014-02-07
Filing date: 2015-02-05
Publication date: 2015-08-13
Also published as: JPWO2015119214A1; JP6168166B2

Abstract

　Insulators (12) having insulating properties cover protruding parts (11b). Wires (13) are wound around the protruding parts (11b), with the insulators (12) interposed therebetween, so as to form coils. Electroconductive bus bars (14-17), formed in an annular shape, electrically connect wires (13) to which power having the same phase is fed. Insulating members (18) are formed in a film shape and interposed between adjacent bus bars (14-17) so as to insulate the adjacent bus bars (14-17) from each other. The insulating members (18) and the bus bars (14-17) are alternatingly layered along the axial direction to form a layered body. Respective end parts (13a, 13b) of wires (13) to which power having mutually different phases is fed are led out radially outwards at different axial positions with respect to the layered body so as to connect to the outer peripheral edge of the bus bars (14-17).

Description

Stator assembly

The present invention relates to a stator assembly.

Conventionally, there is a motor that includes a stator and a rotor and generates mechanical energy such as rotation based on electromagnetic force generated by input electric energy. The stator corresponds to a stator assembly, and there is one in which an electric wire wound around an insulator covering a protruding portion of the stator is connected to a bus bar. In order to reduce the thickness in the axial direction, there is a configuration in which a bus bar unit is incorporated into a stator in which the yoke is thicker in the axial direction than the teeth (see Patent Document 1).

JP 2008-278692 A

However, in the configuration of Patent Document 1, a plurality of power supply bus bars and neutral point bus bars are concentrically arranged. Therefore, in order to connect electric wires having coils to each bus bar, a stator assembly is used. A space is required in the axial direction, and the work related to the connection between the electric wire and each bus bar becomes complicated. Therefore, it is difficult to sufficiently reduce the axial thickness of the stator assembly.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a stator assembly that can be reduced in size by reducing the axial thickness.

The stator assembly according to the present invention that achieves the above object includes a stator, an insulator, an electric wire, a bus bar, and an insulating member. The stator includes a main body portion formed in an annular shape and a plurality of projecting portions formed so as to protrude from the main body portion in a radially inward or outward direction. The insulator has an insulating property and covers the protruding portion. The electric wire is wound around the protrusion via an insulator to form a coil. The bus bar has conductivity and is formed in an annular shape, and electrically connects electric wires to which electric power having the same phase is supplied. The insulating member has an insulating property, is formed in a film shape, and is interposed between adjacent bus bars to insulate each other. The insulating member and the bus bar are alternately stacked along the axial direction to form a stacked body. Here, for the plurality of electric wires to which electric power of different phases is supplied, the respective end portions are drawn out radially outward with different axial positions with respect to the laminate, and are connected to the outer peripheral edge of the bus bar. ing.

It is a perspective view which shows the stator assembly of embodiment. It is a perspective view which expands and shows a part of stator assembly of FIG. It is a disassembled perspective view which decomposes | disassembles and shows the stator assembly of FIG. 1 for every structural member. It is a disassembled perspective view which decomposes | disassembles and shows the laminated body of FIG. 3 for every structural member. It is a perspective view which shows the insulating paper of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. The sizes and ratios of the members in the drawings are exaggerated for convenience of explanation and may be different from the actual sizes and ratios. 3 to 5 show the members at the same magnification. In all the drawings of FIGS. 1 to 5, the azimuth is indicated by using arrows represented by X, Y, and Z. 1 to 5 are illustrated with the same orientation. The direction of the arrow represented by X and Y is the radial direction of the stator 11. The direction of the arrow represented by Z is the axial direction of the stator 11.

(Embodiment)
The stator assembly 10 corresponds to a stator of the motor. The motor includes a stator and a rotor, and generates mechanical energy such as rotation based on electromagnetic force generated by input electric energy. The stator assembly 10 corresponds to, for example, a stator that rotates a rotor housed inside.

The stator assembly 10 will be described with reference to FIGS.

FIG. 1 is a perspective view showing the stator assembly 10. FIG. 2 is an enlarged perspective view showing a part of the stator assembly 10 of FIG. FIG. 3 is an exploded perspective view showing the stator assembly 10 of FIG. FIG. 4 is an exploded perspective view showing the laminated body 20 of FIG. FIG. 5 is a perspective view showing the insulating paper 18 of FIG.

Stator assembly 10 includes a stator 11, an insulator 12, an electric wire 13, a bus bar (U-phase bus bar 14, V-phase bus bar 15, W-phase bus bar 16, and N-phase bus bar 17), and insulating paper 18 (insulating member). . Hereinafter, the constituent members of the stator assembly 10 will be described in order.

The stator 11 includes a main body 11a formed in an annular shape, and a plurality of protrusions 11b formed so as to protrude inward in the radial direction (X direction or Y direction) from the main body 11a. As shown in FIG. 3, the stator 11 is integrally formed with a main body portion 11a and a plurality of protruding portions 11b. The stator 11 is made of a magnetic material. The protruding portion 11 b of the stator 11 winds the electric wire 13 in a coil shape via the insulator 12. When electric power is applied to the electric wire 13, a magnetic field is generated in the stator 11. The stator 11 rotates the rotor housed inside by the generated magnetic field.

The insulator 12 has insulation and covers the protruding portion 11b of the stator 11. The insulator 12 includes a housing upper portion 12M and a housing lower portion 12N, and is configured to sandwich the protruding portion 11b of the stator 11 from both sides along the axial direction. The housing upper portion 12M and the housing lower portion 12N are formed so as to be substantially facing each other in the axial direction (Z direction) as shown in FIG. The upper part 12M and the lower part 12N of the casing cover and insulate one protruding part 11b among the plurality of protruding parts 11b protruding from the main body part 11a of the stator 11.

The insulator 12Ma is integrated by joining the joining edge 12Ma at the lower end of the upper part 12M and the joining edge 12Na at the upper end of the lower part 12N in contact with each other. The protruding portion 11b of the stator 11 is covered with a covering surface 12Mb corresponding to the inner surface of the housing upper portion 12M and a covering surface 12Nb corresponding to the inner surface of the housing lower portion 12N. The electric wire 13 is wound around the winding surface 12Mc corresponding to the outer surface of the casing upper portion 12M and the winding surface 12Nb corresponding to the outer surface of the casing lower portion 12N. The laminated body 20 is inserted through the outer peripheral surface 12Md facing outward in the radial direction (X direction or Y direction) of the upper housing portion 12M and the outer peripheral surface 12Nd facing outward in the radial direction (X direction or Y direction) of the lower housing portion 12N. . As shown in FIG. 3, the laminate 20 is a laminate of bus bars (U-phase bus bar 14, V-phase bus bar 15, W-phase bus bar 16, and N-phase bus bar 17) with an insulating member (insulating paper 18) interposed therebetween. It is.

The electric wire 13 is wound around the protruding portion 11b of the stator 11 via the insulator 12 to form a coil. The electric wire 13 is formed by covering a long copper outer peripheral surface with an insulator. As shown in FIGS. 2 and 3, the electric wire 13 has one end portion 13 a on one side and the other end portion 13 b on the other side opposite to the one side. The one end portion 13a and the other end portion 13b are drawn outward in the radial direction (X direction or Y direction) from the bus bar (for example, the U-phase bus bar 14). The one end portion 13a is caulked and connected to the

concave portions

14e, 15e, or 16e formed on the outer peripheral edge of the U-phase bus bar 14, the V-phase bus bar 15, or the W-phase bus bar 16 while being refracted. is doing. The other end 13 b is connected to the concave portion 17 e of the N-phase bus bar 17 by caulking, for example. The plurality of electric wires 13 wound around the protruding portion 11b are provided with U-phase, V-phase, which are different in phase by 120 degrees via bus bars (U-phase bus bar 14, V-phase bus bar 15, and W-phase bus bar 16). Either W phase power is supplied.

The bus bars (the U-phase bus bar 14, the V-phase bus bar 15, and the W-phase bus bar 16) electrically connect the electric wires 13 to which power of the same phase is supplied. N-phase bus bar 17 is a bus bar corresponding to the ground of U-phase bus bar 14, V-phase bus bar 15, and W-phase bus bar 16. The bus bar (for example, the U-phase bus bar 14) is made of a metal having conductivity and is formed in an annular shape. The bus bar (for example, U-phase bus bar 14) is radially outward (X direction or Y direction) from the stator 11 in order to suppress the thickness of the stator assembly 10 in the axial direction (Z-axis direction). It is arranged so as to be adjacent to at least a part of the stator 11 along the (Z direction).

The bus bars (U-phase bus bar 14, V-phase bus bar 15, W-phase bus bar 16, and N-phase bus bar 17) have a thickness in the axial direction (Z-axis direction) of the stator assembly 10 as shown in FIGS. In order to suppress, in the cross-sectional shape along the axial direction (Z direction) intersecting the radial direction (X direction or Y direction), the length along the axial direction (Z direction) is the radial direction (X direction or Y direction). ) Shorter than the length along. Here, since the amount of electric power that can be applied depends on the cross-sectional area of the bus bar (for example, the U-phase bus bar 14), the cross-sectional shape is changed from a circular shape to a flat shape without changing the cross-sectional area required for transmitting predetermined power. .

The U-phase bus bar 14, the V-phase bus bar 15, and the W-phase bus bar 16 have the same shape, receive power supplied from a three-phase AC power supply, and distribute and supply the power to the electric wire 13 formed in a coil shape. . The U-phase bus bar 14, the V-phase bus bar 15, and the W-phase bus bar 16, as shown in FIG. 3 and the like, have 18 slots in the wire 13 formed in a coil shape. .

In the U-phase bus bar 14, the V-phase bus bar 15, and the W-phase bus bar 16, for example, the U-phase bus bar 14 has an annular shape that is cut out so that one end 14a and the other end 14b face each other, as shown in FIG. Forming. The N-phase bus bar 17 is formed in an annular shape without providing a notch. In the U-phase bus bar 14, the V-phase bus bar 15, the W-phase bus bar 16, and the N-phase bus bar 17, for example, the U-phase bus bar 14 includes a terminal portion 14c for inserting a bolt for fastening an external power receiving wiring. ing. The terminal portion 14c has an axial direction while projecting a part between the one end portion 14a and the other end portion 14b in a U shape with respect to the outside in the radial direction (X direction or Y direction) in order to insert a bolt. It is formed by being folded twice along the (Z direction).

In the U-phase bus bar 14, the V-phase bus bar 15, the W-phase bus bar 16, and the N-phase bus bar 17, for example, the U-phase bus bar 14 is arranged in the radial direction (X direction or Y direction) as shown in FIGS. 2 and 4. ) It has a protrusion 14d that protrudes partially outward. The U-phase bus bar 14, the V-phase bus bar 15, the W-phase bus bar 16, and the N-phase bus bar 17 do not overlap the positions of the

protrusions

14d, 15d, 16d, and 17d with respect to the radial direction (X direction or Y direction). As described above, the positions are different from each other. In the U-phase bus bar 14, the V-phase bus bar 15, the W-phase bus bar 16, and the N-phase bus bar 17, for example, the U-phase bus bar 14 includes a semicircular concave portion 14e with respect to the outer peripheral edge of the protruding portion 14d. The concave portion 14e connects, for example, the one end portion 13a of the electric wire 13 by caulking.

The insulating paper 18 is formed in a film shape with insulating properties and is interposed between adjacent bus bars (for example, the U-phase bus bar 14 and the V-phase bus bar 15) to insulate each other. The insulating paper 18 corresponds to an insulating member. The insulating paper 18 has a width along the radial direction (X direction or Y direction) longer than the width of adjacent bus bars (for example, the U-phase bus bar 14 and the V-phase bus bar 15). FIG. 5A shows a state after the pieces 18a are arranged in a ring shape. FIG. 5B shows a state before the pieces 18a are arranged in an annular shape. The insulating paper 18 is formed from a plurality of pieces 18a, and the pieces 18a are arranged in a ring shape. Adjacent pieces 18a overlap each other at their ends. The insulating paper 18 is made of a thermoplastic plastic such as PPS (polyphenylene sulfide resin), PET ((polyethylene terephthalate), PEN (polyethylene naphthalate resin)).

According to the stator assembly 10 according to the above-described embodiment, the following effects can be obtained.

Stator assembly 10 includes a stator 11, an insulator 12, an electric wire 13, a bus bar (at least any two adjacent to U-phase bus bar 14, V-phase bus bar 15, W-phase bus bar 16, and N-phase bus bar 17), and an insulating member. (Insulating paper 18). The stator 11 includes a main body 11a formed in an annular shape, and a plurality of protrusions 11b formed to protrude inward or outward from the main body 11a in the radial direction (X direction or Y direction). . The insulator 12 has insulating properties and covers the protruding portion 11b. The electric wire 13 is wound around the protrusion 11b via the insulator 12 to form a coil. The bus bar (for example, the U-phase bus bar 14) is formed in a ring shape with electrical conductivity, and electrically connects the electric wires 13 to which power of the same phase is supplied. The insulating member (insulating paper 18) is formed in a film shape with insulating properties, and is insulated from each other by being interposed between adjacent bus bars (for example, the U-phase bus bar 14 and the V-phase bus bar 15). The insulating member (insulating paper 18) and the bus bar (at least two adjacent ones of the U-phase bus bar 14, the V-phase bus bar 15, the W-phase bus bar 16, and the N-phase bus bar 17) are along the axial direction (Z direction). The laminated body 20 is formed by alternately laminating. Here, in the plurality of electric wires 13 to which electric power having different phases is supplied, the positions of the end portions (one end portion 13a and the other end portion 13b) are different from each other in the axial direction (Z direction) with respect to the stacked body 20. Thus, it is drawn outward in the radial direction (X direction or Y direction) and connected to the outer peripheral edge of the bus bar (for example, the U-phase bus bar 14).

According to such a configuration, the end portions (one end portion 13 a and the other end portion 13 b) of the plurality of electric wires 13 are arranged in the radial direction (X direction) with different positions in the axial direction (Z direction) with respect to the stacked body 20. (Or Y direction) After being drawn outward, it is connected to the outer peripheral edge of the bus bar. Therefore, the thickness of the stator assembly 10 in the axial direction (Z direction) can be reduced. That is, the stator assembly 10 can be reduced in size along the axial direction (Z direction).

In particular, according to such a configuration, for example, the end portions (one end portion 13a and the other end portion 13b) of all the electric wires 13 are radially extended from the lower end or the upper end in the axial direction (Z direction) of the laminate 20 (X The thickness in the axial direction (Z direction) caused by the electric wires 13 can also be minimized by pulling out in the outward direction (direction or Y direction). Further, since the sheet-like insulating paper 18 is sandwiched between adjacent bus bars (for example, the U-phase bus bar 14 and the V-phase bus bar 15), the filling failure (filling as in the case of molding an insulating resin) (Insufficient) can be more reliably insulated. Moreover, since the inexpensive insulating paper 18 is used for insulation between adjacent bus bars (for example, the U-phase bus bar 14 and the V-phase bus bar 15), the manufacturing cost can be reduced.

Further, according to such a configuration, even if the bus bar (for example, the U-phase bus bar 14) has a small thickness in the axial direction (Z direction), the bus bar (from the outside in the radial direction (X direction or Y direction) of the stator 11 ( For example, the U-phase bus bar 14) and the wire 13 can be easily connected. That is, a space for connecting the bus bar (for example, the U-phase bus bar 14) and the electric wire 13 can be sufficiently secured outside the stator 11 in the radial direction (X direction or Y direction). Wiring workability can be improved, for example, the jig can be easily approached.

Further, according to such a configuration, the bus bar and the insulating paper 18 are alternately stacked to form the stacked body 20, and then the stacked body 20 is inserted into the outer peripheral portion of the stator 11. Therefore, when the bus bars and the insulating paper 18 are alternately stacked, it is not necessary to consider interference with the stator 11, and the connection workability can be improved.

Furthermore, the bus bar (at least one of the U-phase bus bar 14, the V-phase bus bar 15, the W-phase bus bar 16, and the N-phase bus bar 17) is more radially outward (X direction or Y direction) than the stator 11. And it can be set as the structure arrange | positioned so that it may adjoin at least one part of the stator 11 along an axial direction (Z direction).

According to such a configuration, the bus bars (the U-phase bus bar 14, the V-phase bus bar 15, the W-phase bus bar 16, and the N-phase bus bar 17) and the stator 11 are adjacent to each other along the axial direction (Z direction). The length of the stator assembly 10 in the axial direction (Z direction) can be further shortened by the overlapping length.

Furthermore, the bus bar (for example, the U-phase bus bar 14) includes a concave portion 14e formed by partially cutting away from the outer peripheral edge inward in the radial direction (X direction or Y direction). For example, one end portion 13a) can be connected to the concave portion 14e.

According to such a configuration, after the end portion (for example, one end portion 13a) of the electric wire 13 is inserted into the concave portion 14e, the wire 13 can be reliably connected with the edge of the concave portion 14e as a reference. Further, even if an impact is applied to the end portion (for example, one end portion 13a), the end portion (for example, one end portion 13a) is inserted into the concave portion 14e. It can be made difficult to peel off.

Further, the bus bars (at least two of the U-phase bus bar 14, the V-phase bus bar 15, the W-phase bus bar 16, and the N-phase bus bar 17) are directed outward from the outer peripheral edge in the radial direction (X direction or Y direction). The plurality of bus bars (for example, the U-phase bus bar 14 and the V-phase bus bar 15) are arranged so that the positions of the

respective protrusions

14d and 15d are different from each other in the circumferential direction. The recessed

portions

14e and 15e may be formed on the

protrusions

14d and 15d.

According to such a configuration, when the one end portion 13a of the electric wire 13 is connected to the concave portion 14e of the bus bar (for example, the U-phase bus bar 14), the one end portion 13a comes into contact with the laminated member such as the insulating paper 18. Can be easily prevented. Furthermore, for example, the concave portion 14e of the U-phase bus bar 14 can be sufficiently separated from the adjacent V-phase bus bar 15 and N-phase bus bar 17 to sufficiently prevent such short circuit.

Furthermore, the insulating member (insulating paper 18) can be configured to be interposed in all regions between adjacent bus bars (for example, the U-phase bus bar 14 and the V-phase bus bar 15).

According to such a configuration, discharge in the air layer between adjacent bus bars (for example, the U-phase bus bar 14 and the V-phase bus bar 15) can be sufficiently suppressed. That is, a short circuit between adjacent bus bars (for example, U-phase bus bar 14 and V-phase bus bar 15) can be prevented more reliably.

Furthermore, the insulating member (insulating paper 18) may be formed from a plurality of pieces 18a, and the pieces 18a may be arranged in a ring shape.

According to such a configuration, the portion of the rectangular insulating paper to be discarded can be greatly reduced as compared with the case where the insulating paper 18 is formed by punching out the rectangular insulating paper into a single body. it can. That is, the individual pieces 18a can be formed on the entire surface of the rectangular insulating paper by, for example, punching in a matrix shape with the longitudinal direction aligned, thereby reducing the portion to be discarded in the rectangular insulating paper.

Furthermore, the bus bar (for example, any one or more of the U-phase bus bar 14, the V-phase bus bar 15, the W-phase bus bar 16, and the N-phase bus bar 17) has an axial direction that intersects the radial direction (X direction or Y direction) (Z In the cross-sectional shape along (direction), the length along the axial direction (Z direction) can be made shorter than the length along the radial direction (X direction or Y direction).

According to such a configuration, the stator assembly 10 can be further thinned along the axial direction. The bus bar (for example, the U-phase bus bar 14) changes the cross-sectional shape from a circular shape to a flat shape without changing the necessary cross-sectional area because the amount of electric power that can be applied depends on the cross-sectional area. Moreover, according to such a structure, a bus bar (for example, U-phase bus bar 14) is easy to increase the contact area in an axial direction (Z direction) with respect to another structural member (for example, insulator 12). That is, when vibration or impact is applied to the stator assembly 10 in the axial direction (Z direction), between the bus bar (for example, the U-phase bus bar 14) and other structural members (for example, the insulating paper 18 and the insulator 12). It is easy to disperse stress. Furthermore, the bus bar (for example, the U-phase bus bar 14) can easily increase the static frictional force with other components (for example, the insulating paper 18). That is, the bus bar (for example, the U-phase bus bar 14) is easy to prevent misalignment with other constituent members (for example, the insulating paper 18) even if vibration or impact is applied.

In addition, the present invention can be modified in various ways based on the configuration described in the claims, and these are also within the scope of the present invention.

For example, the one end portion 13a of the electric wire 13 has been described as a structure that is caulked and connected to the concave portion 14e of the U-phase bus bar 14 or the like in a refracted state, but is not limited to such a configuration. . The one end portion 13a of the electric wire 13 may be connected to the concave portion 14e or the like such as the U-phase bus bar 14 by welding or the like while extending in the axial direction (Z direction). In the case of such a configuration, the thickness in the axial direction (Z direction) can be further suppressed.

Further, although the stator assembly 10 corresponding to the stator has been described as a configuration in which the rotor is accommodated and rotated inward, the stator assembly 10 is not limited to such a configuration. The stator assembly 10 may be configured such that a rotor having a cylindrical shape is disposed on the outer side thereof and rotated.

In addition, although the stator assembly 10 has been described as a configuration in which the one protrusion 11b is covered with the insulator 12 including the housing upper portion 12M and the housing lower portion 12N, the present invention is not limited to such a configuration. The insulator may be configured to cover the entire stator 11 including the main body portion 11a and the plurality of protruding portions 11b.

Further, although the stator assembly 10 has been described as having three phases, it may be configured as, for example, five phases. In this case, there are five bus bars except for the N-phase bus bar 17. Further, the stator assembly 10 does not necessarily require the N-phase bus bar 17 if the other end portions 13b of the electric wires 13 are connected to each other.

This application is based on Japanese Patent Application No. 2014-022797 filed on February 7, 2014, the disclosure of which is referenced and incorporated as a whole.

10 Stator assembly,
11 Stator,
11a body part,
11b protrusion,
12 Insulator,
12M upper part of the frame,
12N Lower body,
12Ma, 12Na joint edge,
12Mb, 12Nb coated surface,
12Mc, 12Nc winding surface,
12Md, 12Nd outer peripheral surface,
13 Electric wire,
13a one end,
13b the other end,
14 U-phase bus bar,
15 V-phase bus bar,
16 W phase bus bar,
17 N-phase bus bar,
14a, 15a, 16a, one end,
14b, 15b, 16b the other end,
14c, 15c, 16c terminals,
14d, 15d, 16d, 17d protrusion,
14e, 15e, 16e, 17e concave part,
18 Insulating paper (insulating material),
18a pieces,
20 laminates,
X, Y (stator) radial direction,
Z (stator) axial direction.

Claims

A stator including an annularly formed main body, and a plurality of protrusions formed to protrude radially inward or outward from the main body,
An insulator having insulating properties and covering the protruding portion;
An electric wire wound around the protrusion via the insulator to form a coil;
A bus bar that is formed in a ring shape with electrical conductivity, and that electrically connects the electric wires supplied with the same phase power;
An insulating member that has insulating properties and is formed into a film, and is insulated between the bus bars adjacent to each other;
The insulating member and the bus bar are alternately stacked along the axial direction to form a stacked body,
A plurality of the electric wires to which electric power having different phases are supplied, the end portions of the electric wires are pulled out outward in the radial direction at different positions in the axial direction with respect to the laminated body, and the outer peripheral edge of the bus bar Stator assembly wired to.
2. The stator assembly according to claim 1, wherein the bus bar is disposed radially outward from the stator and adjacent to at least a part of the stator along the axial direction.
The bus bar includes a concave portion formed by partially cutting away from the outer peripheral edge toward the radially inner side,
The stator assembly according to claim 1, wherein the electric wire has the end connected to the concave portion.
The bus bar includes a protruding portion that partially protrudes from the outer peripheral edge toward the radially outer side,
The plurality of bus bars are arranged with the positions of the protrusions different from each other in the circumferential direction,
The stator assembly according to claim 3, wherein the concave portion is formed on the protrusion.
The stator assembly according to any one of claims 1 to 4, wherein the insulating member is interposed in all regions between the adjacent bus bars.
The stator assembly according to any one of claims 1 to 5, wherein the insulating member is formed of a plurality of pieces, and the pieces are arranged in a ring shape.
7. The bus bar according to claim 1, wherein a length along the axial direction is shorter than a length along the radial direction in a cross-sectional shape along the axial direction intersecting the radial direction. The stator assembly according to item 1.