Motor

Abstract

To suppress deformation or breakage of a bobbin.SOLUTION: The motor includes a stator having an insulator and a coil wound around the insulator. The insulator includes a curved portion extending in a radial direction and protruding in a rotation axis direction, and a wall extending in a circumferential direction. One or a plurality of grooves extending in a direction intersecting a direction in which the coil is wound are formed on a surface of the curved portion, and the coil straddles the groove in a circumferential direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a motor. [Background technology]

[0002] It is known that extra-thick winding wires with diameters of approximately 2.0 to 3.0 mm are used in motors that must handle large currents, such as those used in automobiles, and a technique for winding the conductor wire around a pair of bobbins is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-239347 Summary of the Invention [Problem to be solved by the invention]

[0004] The resin used for the bobbin has low rigidity, and when a thick wire is wound around the bobbin, the top part where the most tension is applied may be deformed or damaged. Such deformation or damage to the bobbin can cause the coil wound around the bobbin to collapse or cause poor insulation.

[0005] One aspect of the present invention is to provide a motor that can suppress deformation or damage to the bobbin. [Means for solving the problem]

[0006] In one aspect, a motor includes a stator having an insulator and a coil wound around the insulator. The insulator includes a curved portion extending radially and projecting in the direction of the rotation axis, and a wall extending circumferentially. One or more grooves are formed on the surface of the curved portion, extending in a direction intersecting the direction in which the coil is wound, and the coil straddles the grooves in the circumferential direction.

[0007] According to one aspect, deformation or breakage of the bobbin can be suppressed. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a partial cross-sectional view showing an example of a motor according to a first embodiment. [Figure 2] FIG. 2 is a perspective view showing an example of a split stator according to the first embodiment. [Figure 3] FIG. 3 is an exploded perspective view showing an example of a split stator according to the first embodiment. [Figure 4] FIG. 4 is an enlarged perspective view showing an example of a split stator before a coil is wound thereon in the first embodiment. [Figure 5] FIG. 5 is a diagram showing an example of a process of winding a coil around a split stator according to the first embodiment. [Figure 6] FIG. 6 is a side cross-sectional view showing an example of a portion around which a coil is wound in the first embodiment. [Figure 7] FIG. 7 is a side cross-sectional view showing an example of the motor according to the first embodiment. [Figure 8] FIG. 8 is an enlarged perspective view showing an example of a split stator according to the second embodiment. [Figure 9] FIG. 9 is an enlarged perspective view showing an example of a divided stator according to the first modified example. [Figure 10] FIG. 10 is an enlarged perspective view showing an example of a process for assembling the stator segments in the second modified example. [Figure 11] FIG. 11 is an enlarged perspective view showing an example of a process for assembling the stator segments in the third modified example. [Figure 12] FIG. 12 is an enlarged perspective view showing an example of a divided stator according to the fourth modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of a motor disclosed in the present application will be described in detail with reference to the drawings. Note that the dimensional relationships between elements in the drawings, the ratios between elements, and the like may differ from reality. The drawings may also include portions where the dimensional relationships and ratios between elements differ. To make the description easier to understand, each drawing may illustrate a coordinate system in which the direction in which a shaft 99 (described later) extends (the rotational axis direction) is the Z-axis direction, and the radially outer side of the split stator 10L is the positive side of the Y-axis. Note that the same components are designated by the same reference numerals throughout the description of the embodiments.

[0010] [First embodiment] First, the motor according to the first embodiment will be described with reference to Fig. 1. Fig. 1 is a partial cross-sectional view showing an example of the motor according to the first embodiment. As shown in Fig. 1, the motor 1 according to the first embodiment includes a frame 91, a stator 2, a rotor 92, and a shaft 99. As shown in Fig. 1, the motor 1 according to the first embodiment is a so-called inner rotor type motor in which the rotor 92 is disposed radially inward of the stator 2.

[0011] The shaft 99 is fixed to the center of the rotor 92 in the radial direction and rotates in conjunction with the rotor 92. One or both ends of the shaft 99 in the Z-axis direction protrude outward from the frame 91, as shown in Fig. 1. The Z-axis direction along which the shaft 99 extends is an example of the rotation axis direction.

[0012] Stator 2 in the first embodiment includes, for example, twelve stator segments 10A to 10L. Stator segments 10A to 10L have the same structure, and stator segment 10L may be described below as an example. As shown in Fig. 1, in stator segment 10L, the positive side of the Y axis indicates the radial outside, and the X axis indicates the circumferential direction.

[0013] The stator 2 in the first embodiment is formed by connecting a plurality of split stators 10 shown in Fig. 2 in the circumferential direction. Fig. 2 is a perspective view showing an example of a split stator in the first embodiment. As shown in Figs. 1 and 2, the split stator 10 of the stator 2 in the first embodiment has an insulator 20, a split core 100 housed in the insulator 20, and a coil 400 wound around the insulator 20. The split core 100 is an example of a core housed in an insulator.

[0014] The split core 100 is formed by stacking multiple magnetic bodies, such as magnetic steel plates, in the Z-axis direction. As shown in Fig. 3, the split core 100 includes an inner peripheral portion 110, a connecting portion 120, and an outer peripheral portion 130. Fig. 3 is an exploded perspective view showing an example of a split stator according to the first embodiment. The split core 100 according to the first embodiment is a so-called T-core, which includes portions that protrude in the circumferential direction on both the radially inner and outer sides.

[0015] The inner peripheral portion 110 protrudes on both sides in the circumferential direction from the radially inner side of the split core 100. The outer peripheral portion 130 protrudes on both sides in the circumferential direction from the radially outer side of the split core 100. The connecting portion 120 connects the inner peripheral portion 110 and the outer peripheral portion 130 in the radial direction.

[0016] The coil 400 is formed by winding a conductor such as an insulating coated copper wire around the split core 100 via the insulator 20. In this case, the insulator 20 serves as a bobbin around which the coil 400 is wound. The coil 400 has, for example, two terminals 419 and 429 that protrude toward the positive side of the Z axis. Note that FIG. 3 shows the coil 400 in a separated state after being wound around the split core 100 by a dashed line for the purpose of explanation; in reality, the coil 400 is not separated from the split core 100 while maintaining its wound shape.

[0017] The insulator 20 is an insulating member made of resin or the like that covers the split core 100. As shown in Figs. 2 and 3, the insulator 20 includes an upper insulator 200 and a lower insulator 300. As shown in Fig. 3, the upper insulator 200 is attached to the split core 100 from the positive side in the Z-axis direction, and the lower insulator 300 is attached to the split core 100 from the negative side in the Z-axis direction. In the first embodiment, the coil 400 is wound after the upper insulator 200 and the lower insulator 300 are attached to the split core 100.

[0018] In the first embodiment, the upper insulator 200 and the lower insulator 300 have substantially the same shape. The following description of the shape of the upper insulator 200 may also apply to the lower insulator 300.

[0019] The upper insulator 200 includes an inner circumferential portion 210, a connecting portion 220, an outer circumferential portion 230, and a curved portion 250. The inner circumferential portion 210 contacts a portion of the inner circumferential portion 110 of the split core 100 from the radially outer side. The outer circumferential portion 230 contacts a portion of the outer circumferential portion 130 of the split core 100 from the radially inner side. The connecting portion 220 connects the inner circumferential portion 210 and the outer circumferential portion 230 in the radial direction, and covers the connecting portion 120 of the split core 100 from both circumferential sides and the positive side in the rotation axis direction (Z-axis direction). The inner circumferential portion 210 and the outer circumferential portion 230 are examples of walls extending in the circumferential direction.

[0020] As shown in FIGS. 3 and 4, the curved portion 250 protrudes from the connecting portion 220 in the rotation axis direction (positive direction on the Z axis). FIG. 4 is an enlarged perspective view showing an example of a split stator before a coil is wound thereon in the first embodiment. FIG. 4 is an enlarged view of the portion indicated by frame F1 in FIG. 2 in a state before the coil 400 is wound thereon. As shown in FIG. 4, the curved portion 250 includes an inner surface 271 located on the inside in the radial direction (negative side on the Y axis), an outer surface 272 located on the outside in the radial direction (positive side on the Y axis), and a curved surface 260 extending in the radial direction from the inner surface 271 to the outer surface 272. The curved surface 260 is an example of a surface of the curved portion, and the inner surface 271 and the outer surface 272 are examples of end surfaces of the curved portion 250.

[0021] A groove 280 is formed on the surface 260 of the curved portion 250, extending in a direction in which the coil 400 is wound, for example, in a direction intersecting the X-axis direction shown in Fig. 4. In the first embodiment, the groove 280 extends from the inner surface 271 to the outer surface 272 in a radial direction, for example, in the Y-axis direction shown in Fig. 4. Furthermore, the apexes 261 and 262 of the curved portion 250 are formed on both sides of the groove 280 in a circumferential direction, for example, in the X-axis direction shown in Fig. 4.

[0022] The lower insulator 300 includes an inner circumferential portion 310, a connecting portion 320, an outer circumferential portion 330, and a curved portion 350. The inner circumferential portion 310 contacts a portion of the inner circumferential portion 110 of the split core 100 from the radially outer side. The outer circumferential portion 330 contacts a portion of the outer circumferential portion 130 of the split core 100 from the radially inner side. The connecting portion 320 connects the inner circumferential portion 310 and the outer circumferential portion 330 in the radial direction and covers the connecting portion 120 of the split core 100 from both circumferential sides and the negative side of the rotation axis (Z-axis direction). The inner circumferential portion 310 and the outer circumferential portion 330 are another example of a wall extending in the circumferential direction.

[0023] As described above, the insulator 20 includes the curved portions 250, 350 extending radially and protruding in the rotation axis direction, and the walls 210, 230, 310, 330 extending circumferentially. Also, as shown in Fig. 3, the connection portion 220 of the upper insulator 200 includes side surfaces 221, 222 extending from the curved portion 250 in the rotation axis direction (Z-axis direction).

[0024] When the coil 400 is wound around the split core 100, a jig 800 such as that shown in Fig. 5 is placed on the curved portions 250 and 350 of the insulator 20. Fig. 5 is a diagram showing an example of the process of winding the coil around the split stator in the first embodiment. As shown in Fig. 5, the jig 800 includes two support plates 810 and 820 and a pin 830.

[0025] 5, pin 830 is disposed in groove 280 of curved portion 250 and groove 380 of curved portion 350. Support plates 810 and 820 are attached to pin 830 from opposite sides in the radial direction, as shown by dashed lines in FIG.

[0026] In this configuration, the coil 400 is wound around the split core 100 via the insulator 20 so as to contact the pin 830 arranged on the curved portion 350, as shown by the dashed line in Fig. 5. Furthermore, the support plates 810 and 820 support the coil 400 from both sides in the radial direction, thereby preventing the coil 400 from collapsing when being wound. Note that Fig. 5 omits the illustration of the coil 400 other than the portion shown by the dashed line.

[0027] In this case, as shown in Fig. 6, the coil 400 is wound without contacting the apexes 361 and 362 of the curved portion 350 in the axial direction. Fig. 6 is a side cross-sectional view showing an example of a portion around which a coil is wound in the first embodiment. Fig. 6 shows a cross section taken along line BB in Fig. 2, and illustrates a state in which the jig 800 shown in Fig. 5 has been removed after the coil 400 has been wound. After the coil 400 has been wound, the jig 800 is removed from the split stator 10 by, for example, removing the support plate 810 or 820 from the pin 830 and pulling out the remaining support plate and pin 830 in the radial direction (the Y-axis direction shown in Fig. 5).

[0028] As shown in Fig. 6, the coil 400 is wound around the curved portion 350 without contacting the apexes 361 and 362. At this time, the coil 400 straddles the groove 380 of the curved portion 350 in the circumferential direction, for example, in the X-axis direction shown in Fig. 6. Note that, as shown in Fig. 6, the lower insulator 300 also has side surfaces 321 and 322, similar to the upper insulator 200.

[0029] According to this configuration, the tension of the coil 400 is prevented from concentrating on parts such as the apexes 361 and 362 on the curved portion 350, and is dispersed to the curved surface 360, etc. This prevents the insulator 20, which is made of resin, from being deformed or damaged by the tension of the coil 400, making it difficult for the coil 400 to become unwound.

[0030] This makes it possible to omit walls or the like for preventing the coil 400 from becoming unwound from the split stator 10. For example, as shown in Fig. 4, the curved portions 250 of the insulators 20 protrude from the end faces 111 of the inner peripheral portions 110 of the split cores 100 in the direction of the rotation axis (Z-axis). Similarly, as shown in Fig. 4, the curved portions 250 of the insulators 20 protrude from the end faces 131 of the outer peripheral portions 130 in the positive direction in the Z-axis direction. Similarly, the curved portions 350 of the lower insulators 300 protrude from the end faces 131 of the outer peripheral portions 130 in the negative direction in the Z-axis direction.

[0031] Furthermore, the inner peripheral portion 210 and the outer peripheral portion 230 of the upper insulator 200 are connected to the side surface 221 of the connecting portion 220. In this case, the end faces 211 and 231 on the positive side in the Z-axis direction of the inner peripheral portion 210 and the outer peripheral portion 230 are formed so as to be approximately flush with the end faces 111 and 131 of the split core 100, respectively.

[0032] In this configuration, an end face 271 of the curved portion 250 faces the rotor 92 in the radial direction, for example, in the Y-axis direction shown in FIG. 7 . FIG. 7 is a side cross-sectional view showing an example of a motor according to the first embodiment. FIG. 7 shows a cross section taken along line AA in FIG. 1 . Note that the frame 91 is not shown in FIG. 7 . As shown in FIG. 7 , the curved portion 250 faces the rotor 92 directly in the radial direction (Y-axis direction) without being sandwiched between the inner circumferential portion 110 of the split core 100 and the wall 210 of the upper insulator 200. This configuration allows the motor 1 to be lightweight. Similarly, the outer end face 272 of the curved portion 250 in the radial direction may also face the frame 91 shown in FIG. 1 directly without being sandwiched between the outer circumferential portion 130 of the split core 100 and the wall 230 of the upper insulator 200.

[0033] As described above, the motor 1 in the first embodiment includes a stator 2 having an insulator 20 and a coil 400 wound around the insulator 20. The insulator 20 includes curved portions 250, 350 extending radially and protruding in the direction of the rotation axis, and walls 210, 230, 310, 330 extending circumferentially. One or more grooves 280, 380 are formed on surfaces 260, 360 of the curved portions 250, 350, extending in a direction intersecting the winding direction of the coil 400, and the coil 400 straddles the grooves 280, 380 in the circumferential direction. With this configuration, the tension applied from the coil 400 to the insulator 20 is dispersed without being concentrated in one area, thereby suppressing deformation or damage to the bobbin.

[0034] [Second embodiment] Furthermore, the number of grooves formed in the curved portion of the insulator is not limited to one, and multiple grooves may be formed as shown in Fig. 8. Fig. 8 is an enlarged perspective view showing an example of a split stator in the second embodiment. In Fig. 8, only a portion of the coil 400 is shown by a dashed line, and other portions of the coil 400 are not shown. In the following embodiments and modifications, the same parts as those shown in the drawings described above are designated by the same reference numerals, and duplicated explanations will be omitted.

[0035] As shown in Fig. 8, the split stator 30L of the second embodiment includes an insulator 50, a split core 100, and a coil 400. The upper insulator 500 of the insulator 50 includes an inner circumferential portion 210, a connecting portion 220, an outer circumferential portion 130, and a curved portion 550. Three grooves 581 to 583 are formed in a curved surface 560 of the curved portion 550. The lower insulator 600 of the insulator 50 has, for example, the same shape as the upper insulator 500. That is, the lower insulator 600 may also have three grooves formed in a curved portion 650 (not shown) similar to the upper insulator 500.

[0036] In the second embodiment, jig 900 used when winding coil 400 around upper insulator 500 and lower insulator 600 may have three pins 931 to 933 as shown in Fig. 8. In the second embodiment as well, jig 900 is removed from split stator 30L by, for example, removing support plate 910 or 920 from pins 931 to 933 and then pulling out the remaining support plate and pins 931 to 933 in the radial direction (the Y-axis direction shown in Fig. 5).

[0037] As described above, the motor of the second embodiment includes a stator having an insulator 50 and a coil 400 wound around the insulator 50. The insulator 50 includes a curved portion 550 that extends radially and protrudes in the direction of the rotation axis, and walls 210 and 230 that extend circumferentially. A surface 560 of the curved portion 250 is formed with a plurality of grooves 581 to 583 that extend in a direction intersecting the direction in which the coil 400 is wound, and the coil 400 straddles the grooves 581 to 583 in the circumferential direction. With this configuration, tension generated when the coil 400 is wound is distributed to the pins 931 to 933 that are arranged in the plurality of grooves 581 to 583.

[0038] [Variations] Although the configurations of the respective embodiments have been described above, the embodiments are not limited to these. For example, the grooves 280, etc. may be formed at an angle relative to the radial direction as long as they intersect with the winding direction of the coil 400. The number of grooves 280, etc. may be two or four or more, but it is preferable that they are formed at the vertices of the curved portion 250 in the Z-axis direction in order to distribute the tension caused by the coil 400.

[0039] Furthermore, the motor is not limited to a so-called inner rotor type, but may be a so-called outer rotor type in which the rotor 92 is disposed radially outward from the stator 2. Furthermore, the split core 100 may be a so-called I-shaped core that does not have a portion that protrudes circumferentially on the radially outer or inner side.

[0040] Furthermore, although a configuration in which the upper insulator and the lower insulator have approximately the same shape has been described, this is not limited to this, and a configuration in which a curved portion is formed on only one of them may also be used, and the shape and size of the curved portion may be different between the top and bottom.

[0041] 9 and other figures, another member may be placed in groove 280 or the like even after coil 400 is wound. Fig. 9 is an enlarged perspective view showing an example of a split stator in the first modified example. Fig. 9 shows an enlarged view of the portion of split stator A10L in the first modified example indicated by frame F1 in Fig. 2.

[0042] After the coil 400 is wound around the groove 280 of the insulator 20 in Fig. 9, the groove 280 becomes an adhesive reservoir after the jig 800 is removed. Note that the adhesive 710 is filled not only in the portion visible in Fig. 9 but also in the portion hidden by the coil 400 and not visible.

[0043] As described above, in the first modified example, adhesive 710 is disposed between coil 400 and groove 280. With this configuration, it is possible to prevent the winding of coil 400 from shifting position or becoming loose.

[0044] Furthermore, when winding the coil 400, instead of a jig, an elastic member such as a thermosetting resin may be placed in the groove 581 or the like as shown in FIG. 10. FIG. 10 is an enlarged perspective view showing an example of the assembly process of the split stator in the second modified example. In FIG. 10, the upper insulator 500 used is that of the second embodiment, and the lower insulator 300 used is that of the first embodiment. That is, in the second modified example, the upper insulator 500 and the lower insulator 300 are asymmetrical.

[0045] As shown in Fig. 10, in a split stator B10L according to the second modification, an elastic member 720 such as a thermosetting resin is placed in grooves 581 and 583 of upper insulator 500 before coil 400 is wound therearound. In this case, instead of jig 900 having three pins 931 to 933 used in the second embodiment, jig 800 having only one pin 830 used in the first embodiment may be used, as shown in Fig. 10. Note that elastic member 720 is an example of a resin member, and when multiple elastic members 720 are individually referred to, they may be referred to as elastic members 721 and 723, respectively.

[0046] Coil 400 in the second modified example is wound around so as to contact pin 830 of jig 800 and elastic members 721 and 723. At this time, elastic members 721 and 723 deform so as to fit the shape of coil 400. After coil 400 is wound around, elastic members 721 and 723 are heated and hardened, whereby elastic members 721 and 723 are fixed in a shape that fits coil 400.

[0047] As described above, in the second modified example, resin member 720 is disposed in groove 581 and groove 583, and coil 400 is wound around insulator 50 via resin member 720. With this configuration, it is possible to further prevent coil 400 from becoming unwound, etc.

[0048] 11, other components may be placed on the curved portion 250 of the insulator 20 before the coil 400 is wound thereon. FIG. 11 is an enlarged perspective view showing an example of the assembly process of the split stator in the third modified example. The cover 730 shown in FIG. 11 is made of a metal such as copper, and covers the curved portion 250 from the positive side along the Z axis. The cover 730 may also be formed with a protrusion 731 that fits into the groove 280. In this case, the coil 400 is wound around the split core 100 via the cover 730 and the insulator 20. The cover 730 may also be similarly placed on the lower insulator 300.

[0049] As described above, the split stator C10L in the third modified example includes the cover 730 that covers the curved portion 250 of the insulator 20 in the rotation axis direction, for example, from the positive side of the Z axis, and the coil 400 is wound around the insulator 20 via the cover 730. With this configuration, heat from the coil 400 is transmitted to the cover 730, thereby improving the heat dissipation performance of the coil 400. Also, a cover may be disposed on the upper insulator 500 or the lower insulator 600 in the second embodiment. In this case, the cover may have a plurality of protrusions formed thereon so as to fit into a plurality of grooves formed in the upper insulator 500 and the lower insulator 600.

[0050] Furthermore, as shown in Fig. 12, the insulator may be configured to have a flange portion at a position that does not face the curved portion. Fig. 12 is an enlarged perspective view showing an example of a split stator in a fourth modified example. As shown in Fig. 12, the inner peripheral portion E10 of the upper insulator E00 of the split stator D10L in the fourth modified example has a portion E19 that protrudes axially beyond the split core 100, for example, toward the positive side of the Z axis shown in Fig. 12. Similarly, the outer peripheral portion E30 has a portion E39 that protrudes axially beyond the split core 100. The inner peripheral portion E10 and the outer peripheral portion E30 are examples of walls extending in the circumferential direction.

[0051] 12, an inner surface 271 of the curved portion 250 of the insulator 20 is adjacent to the protruding portion E19 in the circumferential direction and is exposed radially inward (toward the negative direction on the Y axis) relative to the protruding portion E19. Similarly, an outer surface 272 of the curved portion 250 is adjacent to the protruding portion E39 in the circumferential direction and is exposed radially outward (toward the positive direction on the Y axis) relative to the protruding portion E39.

[0052] As described above, in the fourth modified example, the walls E10 and E30 have portions E19 and E39 that protrude radially beyond the split core 100. The curved portions are adjacent to the protruding portions E19 and E39 in the circumferential direction and are exposed to the protruding portions E19 and E39 in the radial direction. Even in this configuration, the curved portions 250 distribute the tension of the coil 400, thereby preventing the coil 400 from becoming unwound. Note that the protruding portions E19 and E39 are formed symmetrically in the circumferential direction, but the protruding portions may be formed asymmetrically, for example, by forming a portion that protrudes only on one side in the circumferential direction.

[0053] Although the present invention has been described above based on the embodiments and modifications thereof, it goes without saying that the present invention is not limited to the embodiments and modifications thereof, and various modifications are possible without departing from the spirit of the present invention. Such modifications without departing from the spirit of the present invention are also included in the technical scope of the present invention, and this will be clear to those skilled in the art from the description of the claims. [Explanation of symbols]

[0054] 1 motor, 2 stator, 10, 10A to 10L, 30L, A10L, B10L, C10L, D10L split stator, 20, 50 insulator, 91 frame, 92 rotor, 99 shaft, 100 split core, 110 inner periphery, 120 connection part, 130 outer periphery, 111, 131 end face, 200, 500, E00 upper insulator, 300, 600 lower insulator, 210, 310, E10 inner periphery, 220, 320 connection part, 221, 222, 321, 322 side, 230, 330, E30 outer periphery, 211, 231 end face, E19, E39 protruding part, 250, 350, 550, 650 Curved portion, 260, 360, 560 Curved surface, 261, 262, 361, 362 Top, 271 Inner surface, 272 Outer surface, 280, 380, 581-583 Groove, 400 Coil, 710 Adhesive, 720, 721, 723 Elastic member, 730 Cover, 731 Protrusion, 800, 900 Jig, 810, 820, 910, 920 Support plate, 830, 931-933 Pin

Claims

1. an insulator, and a coil wound around the insulator; a stator having the insulator includes a curved portion extending radially and protruding in the direction of the rotation axis, and a wall extending circumferentially; One or more grooves are formed on the surface of the curved portion, the grooves extending in a direction intersecting the direction in which the coil is wound, The coil straddles the groove in the circumferential direction. Motor.

2. the stator includes a core housed in the insulator, The curved portion of the insulator protrudes from an end face of the core in the direction of the rotation axis. The motor according to claim 1 .

3. the insulator has a side surface extending from the curved portion in the rotation axis direction, The motor of claim 2 , wherein the wall is continuous with the side surface.

4. a rotor; an end surface of the curved portion faces the rotor in the radial direction; 4. The motor according to claim 1.

5. The motor of claim 1 , wherein an adhesive is disposed between the coil and the groove.

6. A resin member is disposed in the groove, The coil is wound around the insulator via the resin member.

6. The motor according to claim 1.

7. a cover that covers the curved portion of the insulator in the rotation axis direction, The coil is wound around the insulator via the cover.

7. The motor according to claim 1.

8. the wall has a portion that protrudes beyond the core in a radial direction, The curved portion is adjacent to the wall in the circumferential direction and is exposed to the wall. The motor according to claim 3.

Images