Motors, vehicles

Abstract

To provide a motor and vehicle, capable of achieving high transmission efficiency of torque from a reduction gear to a hub.SOLUTION: A motor 1 includes a reduction gear 6 and a hub 7 rotatable around a center shaft CX. The reduction gear 6 has an annular gear 67 rotatable around the center shaft CX, surrounding the center shaft CX. The annular gear 67 has a first contact part 673. The hub 7 has a disk hub 71 surrounding the center shaft CX. The disk hub 71 has a disk part 711 and a second contact part 712. The disk part 711 is arranged on one side in the axial direction rather than the annular gear 67 and spreads in the radial direction, surrounding the center shaft CX. The second contact part 712 is arranged on the other side of the disk part 711 in the axial direction and can comes into contact with the first contact part 673 in the circumferential direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Hub motors mounted on the front wheels of electric bicycles are well known. The driving force of the hub motor is transmitted to the hub, which rotates integrally with the tire, via a reduction gear such as a planetary gear mechanism (see, for example, JP 2019-38480 A).

[0003] The output gear of the reduction gear (for example, the internal gear of a planetary gear mechanism) is axially connected to the hub by, for example, screwing. In order to screw the two together, it is necessary to ensure that the output gear has enough space to screw the output part of the reduction gear. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-38480 Summary of the Invention [Problem to be solved by the invention]

[0005] However, securing the aforementioned space makes it difficult to increase the number of teeth on the output gear, which makes it difficult to improve the efficiency of torque transmission from the reduction gear to the hub. For example, in the case of an internal gear, it is difficult to increase the number of teeth on the radially inner side. This makes it difficult to output a large torque from the internal gear to the hub.

[0006] An object of the present invention is to improve the efficiency of torque transmission from the reduction gear to the hub. [Means for solving the problem]

[0007] An exemplary motor of the present invention includes a shaft, a rotor, a stator, a reduction gear, and a hub. The shaft extends along a central axis extending in the axial direction. The rotor is rotatable together with the shaft about the central axis. The stator is radially opposed to the rotor. The reduction gear is connected to the shaft. The hub is rotatable about the central axis. The reduction gear has an annular gear. The annular gear surrounds the central axis and is rotatable about the central axis. The annular gear has a first contact portion. The hub has a disc hub surrounding the central axis. The disc hub has a disc portion and a second contact portion. The disc portion is located on one side of the annular gear in the axial direction and extends radially around the central axis. The second contact portion is located on the other side of the disc portion in the axial direction and is capable of circumferential contact with the first contact portion.

[0008] An exemplary vehicle of the present invention includes the motor described above. [Effects of the Invention]

[0009] According to the exemplary motor and vehicle of the present invention, the efficiency of torque transmission from the reduction gear to the hub can be improved. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view of the motor. [Figure 2] FIG. 2 is an external view of the motor. [Figure 3] FIG. 3 is an exploded perspective view of the hub and ring gear. [Figure 4] FIG. 4 is an external view of the other axial side of the disc hub. [Figure 5] FIG. 5 is an external view of an assembly of a disc hub and an annular gear according to the embodiment. [Figure 6] FIG. 6 is a diagram showing a connection structure of the first contact portion and the second contact portion. [Figure 7] FIG. 7 is an external view of an assembly of a disk hub and an annular gear according to a modified example. [Figure 8] FIG. 8 is a side view of an annular gear showing an example of the configuration of a flange recess. [Figure 9] FIG. 9 is a cross-sectional view showing the positional relationship between the flange recess and the rib. [Figure 10] FIG. 10 is a side view of an annular gear showing another example of the configuration of the flange recess. [Figure 11] FIG. 11 is a schematic diagram of a vehicle equipped with a motor. DETAILED DESCRIPTION OF THE INVENTION

[0011] Exemplary embodiments will now be described with reference to the drawings.

[0012] In this specification, the direction parallel to the central axis CX, which is the center of rotation of the motor 1, is referred to as the "axial direction." Within the axial direction, the direction from the rotor 3 to the disc hub 71, which will be described later, is referred to as the "one axial direction Da," and the direction from the disc hub 71 to the rotor 3 is referred to as the "other axial direction Db." Additionally, the direction perpendicular to the central axis CX is referred to as the "radial direction," and the direction of rotation around the central axis CX is referred to as the "circumferential direction." Within the radial direction, the direction approaching the central axis CX is referred to as the "radial inward direction," and the direction away from the central axis CX is referred to as the "radial outward direction."

[0013] In this specification, the term "annular" includes not only a shape that is continuous and uninterrupted throughout the entire area in the direction around a predetermined axis such as the central axis CX, but also a shape that has one or more interruptions in a portion of the entire area centered on the axis. It also includes a shape that describes a closed curve on a curved surface that intersects with the central axis CX and is centered on the axis.

[0014] Furthermore, in the positional relationship between one of a direction, a line, and a plane and another, "parallel" includes not only a state in which they do not intersect at all no matter how far they are extended, but also a state in which they are substantially parallel. Furthermore, "perpendicular" and "orthogonal" each include not only a state in which they intersect at 90 degrees, but also a state in which they are substantially perpendicular and a state in which they are substantially orthogonal. In other words, "parallel," "perpendicular," and "orthogonal" each include a state in which there is an angular deviation in the positional relationship between the two to an extent that does not deviate from the spirit of the present invention.

[0015] It should be noted that these are names used merely for the purpose of explanation and are not intended to limit the actual positional relationships, directions, names, etc.

[0016] <1. Motor 1> Fig. 1 is a cross-sectional view of the motor 1. Fig. 2 is an external view of the motor 1. Fig. 1 shows the cross-sectional structure of the motor 1 cut along an imaginary plane including the central axis CX.

[0017] The motor 1 includes a shaft 2, a rotor 3, a stator 4, a stator holder 5, a reduction gear 6, and a hub .

[0018] <1-1. Shaft 2> The shaft 2 has a cylindrical shape that is rotatable around the central axis CX. As described above, the motor 1 includes the shaft 2. The shaft 2 extends in the axial direction along the central axis CX. The central axis CX also extends in the axial direction. The rotor 3 and a sun gear 62 (described later) of the reduction gear 6 are arranged on the radially outer surface of the shaft 2. The shaft 2 rotatably supports the rotor 3 and the sun gear 62.

[0019] <1-2. Rotor 3> The rotor 3 is rotatable together with the shaft 2 about a central axis CX extending in the axial direction. As described above, the motor 1 includes the rotor 3. The rotor 3 has a one-way clutch 31, a rotor core 32, and a magnet 33. The one-way clutch 31 is cylindrical and surrounds the central axis CX, and is fixed to the radially outer surface of the shaft 2. The rotor core 32 is fixed to the radially outer end of the one-way clutch 31 and extends axially around the shaft 2. The rotor core 32 is formed using a magnetic material and functions as a yoke for the magnet 33. In this embodiment, the rotor core 32 is a laminated body in which annular electromagnetic steel plates extending in the radial direction are stacked in the axial direction. The magnet 33 is disposed on the radially outer surface of the rotor core 32. In the magnet 33, different magnetic poles (north and south poles) are alternately arranged in the circumferential direction. The magnet 33 may be an annular member surrounding the central axis CX, or may include a plurality of magnetic pieces arranged in the circumferential direction.

[0020] <1-3. Stator 4> The stator 4 faces the rotor 3 in the radial direction. As described above, the motor 1 includes the stator 4. The stator 4 is disposed radially outward of the rotor 3. The stator 4 includes a stator core 41, an insulator 42, and a plurality of coil portions 43. The stator core 41 is formed using a magnetic material, and in this embodiment, is a laminate in which electromagnetic steel sheets are stacked in the axial direction. The insulator 42 is formed from an electrically insulating material such as resin. The coil portions 43 are components in which a conductor wire (not shown) is disposed on the stator core 41 via the insulator 42. The conductor wire is, for example, an enamel-coated copper wire or a metal wire coated with an insulating material, and is wound around the stator core 41 to form the coil portion 43. When a drive current is supplied to each coil portion 43, the stator 4 is excited and drives the rotor 3.

[0021] <1-4. Stator holder 5> The stator holder 5 holds the stator 4. The stator holder 5 includes a cylindrical bearing holder 51, a bearing 511, a bracket 52, a holder portion 53, and a base plate 54. The bearing holder 51 surrounds the central axis CX and extends in the axial direction. The end of the shaft 2 on the other axial direction Db is inserted into the bearing holder 51. A bearing 511 is disposed on the radially inner surface of the bearing holder 51. The bearing holder 51 rotatably supports the end of the shaft 2 on the other axial direction Db via the bearing 511. The bracket 52 extends radially outward from the end of the bearing holder 51 on the other axial direction Db. An end of the axle 113 on the one axial direction Da, which will be described later, is connected to the bracket 52. The axle 113 extends from the bracket 52 in the other axial direction Db. The holder portion 53 extends from the radially outer end of the bracket 52 in the one axial direction Da and extends circumferentially. The holder portion 53 surrounds the end portion of the stator 4 on the other axial direction Db side. The end portion of the stator core 41 on the other axial direction Db side is fixed to the radially inner surface of the holder portion 53. The substrate 54 is disposed radially outward from the bearing holder 51 and extends radially. The substrate 54 mounts various electronic components such as a drive unit for the stator 4, and is supported by a support portion 521 that protrudes from the bracket 52 in the one axial direction Da.

[0022] <1-5. Decelerator 6> The reduction gear 6 is connected to the shaft 2. As described above, the motor 1 includes the reduction gear 6. In practice, the input side of the reduction gear 6 is connected to the shaft 2. The output side of the reduction gear 6 is connected to the hub 7. In this embodiment, the reduction gear 6 is a planetary gear mechanism, which reduces the rotation of the rotor 3 transmitted from the shaft 2 at a predetermined reduction ratio and transmits the reduced rotation to the hub 7. The reduction gear 6 has a base 61, a sun gear 62, a plurality of planet shafts 63, a planet carrier 64, a plurality of planet gears 65, a plurality of pinion gears 66, and an annular gear 67. The annular gear 67 will be described later.

[0023] The base 61 is fixed to one axial end of the stator 4 and supports the other axial end Db of each planetary shaft 63. The base 61 includes a cylindrical bearing holder 611, a bearing 6111, a base plate portion 612, and a base cylindrical portion 613. The bearing holder 611 surrounds the central axis CX and extends in the axial direction. The shaft 2 is inserted into the bearing holder 611. A bearing 6111 is disposed on the radially inner surface of the bearing holder 611. The bearing holder 611 rotatably supports the shaft 2 via the bearing 6111. The base plate portion 612 extends radially outward from the end of the bearing holder 611 on the one axial end Da. The end of the axle 112 on the other axial end Db, which will be described later, is connected to the base plate portion 612. The axle 112 extends from the base plate portion 612 in the one axial end Da. The base cylindrical portion 613 extends from the radially outer end of the base plate portion 612 in the other axial direction Db and expands in the circumferential direction. The base cylindrical portion 613 surrounds the end of the stator 4 on the one axial direction Da side. The end of the stator core 41 on the one axial direction Da side is fixed to the radially inner surface of the base cylindrical portion 613.

[0024] The sun gear 62 is fixed to the radially outer surface of the shaft 2 and is rotatable about the central axis CX together with the shaft 2. The sun gear 62 may be integral with the shaft 2, or may be separate from the shaft 2 and firmly fixed to the radially outer surface of the shaft 2.

[0025] The planetary shafts 63 are arranged radially outward of the sun gear 62 and along the radially outer end of the sun gear 62. The planetary shafts 63 extend in the axial direction, aligned in the circumferential direction centered on the central axis CX. The ends of the planetary shafts 63 on one axial side Da are connected to the planet carrier 64. The ends of the planetary shafts 63 on the other axial side Db are connected to the base plate portion 612.

[0026] One planet gear 65 and one pinion gear 66 are rotatably arranged on the radially outer surface of each planet shaft 63. The planet gear 65 and the pinion gear 66 are aligned in the circumferential direction centered on the central axis CX.

[0027] The planetary carrier 64 is connected to the end of the axle 112 (described later) on the other axial side Db, and supports the end of each planetary shaft 63 on the one axial side Da. The axle 112 is positioned on the one axial side Da from the shaft 2, and extends in the axial direction. The planetary carrier 64 is positioned on the one axial side Da from the base 61, and extends radially outward from the axle 112.

[0028] The planet gear 65 and the pinion gear 66 are disposed axially between the base 61 and the planet carrier 64. The planet gear 65 is disposed around the sun gear 62 and meshes with the sun gear 62. The planet gear 65 is rotatable about the planet shaft 63 relative to the base 61, for example.

[0029] The pinion gear 66 is disposed coaxially with the planetary gear 65 on one axial direction Da side of the planetary gear 65 and is rotatable together with the planetary gear 65. In this embodiment, the pinion gear 66 is integral with the planetary gear 65, but may be separate from the planetary gear 65. Each pinion gear 66 meshes with an annular gear 67.

[0030] <1-6. Annular Gear 67> Next, the ring gear 67 will be described with reference to FIGS. 1 to 3. FIG. 3 is an exploded perspective view of the hub 7 and the ring gear 67. In this embodiment, the ring gear 67 is a so-called internal gear of a planetary gear mechanism. The ring gear 67 surrounds the central axis CX and is rotatable about the central axis CX. As described above, the reduction gear 6 includes the ring gear 67. The ring gear 67 is disposed radially outward of the pinion gear 66 and meshes with the pinion gear 66. The ring gear 67 is also connected to the hub 7 and transmits the output of the reduction gear 6 to the hub 7. The connection structure between the ring gear 67 and the hub 7 will be described later.

[0031] The annular gear 67 has a gear cylinder portion 671 and a flange portion 672. The gear cylinder portion 671 is cylindrical about the central axis CX, extends in the axial direction, and surrounds the planetary carrier 64 and the plurality of pinion gears 66. A plurality of teeth (not shown) arranged in the circumferential direction are arranged on the radially inner surface of the gear cylinder portion 671. The plurality of teeth mesh with each of the pinion gears 66. As a result, the annular gear 67 rotates in the circumferential direction about the central axis CX in response to the rotation of the pinion gears 66. The flange portion 672 extends radially outward from the radially outer end of the gear cylinder portion 671 and in the circumferential direction, and in this embodiment is annular and surrounds the gear cylinder portion 671.

[0032] The annular gear 67 further has a first contact portion 673. The first contact portion 673 is disposed at the end of the flange portion 672 on one axial side Da, and comes into circumferential contact with a second contact portion 712 of the disc hub 71, which will be described later. Details of the first contact portion 673 will be described later.

[0033] In this embodiment, the material of the annular gear 67 is resin. This allows the annular gear 67 to be lighter than when the annular gear 67 is made of metal, and the first contact portion 673 is more likely to elastically deform in the circumferential direction. Therefore, even if there are locations where the first contact portion 673 and the second contact portion 712 are not in contact with each other due to the tolerance of the first contact portion 673 and the second contact portion 712 when no torque is applied between them in the circumferential direction, when torque is applied between them, the first contact portion 673 elastically deforms and the second contact portion 712 can contact each other at those locations. Therefore, a reduction in the torque transmission efficiency of the annular gear 67 to the disc hub 71 can be prevented. However, the examples of this embodiment do not exclude configurations in which the annular gear 67 is made of a material other than resin.

[0034] <1-7. Hub 7> Next, the hub 7 will be described with reference to Figures 1 to 5. Figure 4 is an external view of the other axial direction Db side of the disc hub 71. Figure 5 is an external view of an assembly of the ring gear 67 and the disc hub 71 according to the embodiment. The hub 7 is rotatable around the central axis CX. As described above, the motor 1 includes the hub 7. The rotation of the rotor 3 is transmitted from the ring gear 67 to the hub 7 via the shaft 2 and the reduction gear 6. The material of the hub 7 is a metal such as aluminum or an alloy thereof.

[0035] The hub 7 has a disk hub 71 and a cylindrical hub portion 72 having a bottom.

[0036] The disc hub 71 is connected to the annular gear 67. As described above, the hub 7 includes the disc hub 71. The disc hub 71 has a disc shape surrounding the central axis CX. The disc hub 71 includes a disc portion 711 and a second contact portion 712. The disc portion 711 is disposed on one axial side Da from the annular gear 67 and extends radially around the central axis CX. The second contact portion 712 is disposed on the other axial side Db of the disc portion 711 and can come into circumferential contact with the first contact portion 673. For example, when the annular gear 67 rotates in one circumferential direction, one circumferential end of the second contact portion 712 comes into circumferential contact with the other circumferential end of the first contact portion 673. Note that when no torque is applied to the annular gear 67, the second contact portion 712 may or may not come into circumferential contact with the first contact portion 673 in the circumferential direction. By bringing the first contact portion 673 of the annular gear 67 into circumferential contact with the second contact portion 712 of the disc hub 71, the rotation of the annular gear 67 can be transmitted to the disc hub 71. Therefore, even if a part that axially connects the annular gear 67 of the reduction gear 6 and the disc hub 71 is not provided, the rotation can be transmitted from the rotor 3 to the hub 7 via the shaft 2 and the reduction gear 6. This improves the efficiency of torque transmission from the reduction gear 6 to the hub 7. Details of the second contact portion 712 will be described later.

[0037] The disc hub 71 also has a bearing holder 713, a bearing 7131, and a connecting portion 714. The bearing holder 713 surrounds the central axis CX and extends in the axial direction. The axle 112 is inserted through the bearing holder 713. The bearing 7131 is disposed on the radially inner surface of the bearing holder 713. The bearing holder 713 rotatably supports the axle 112 via the bearing 7131.

[0038] The connecting portion 714 is disposed at the radially outer end of the disk portion 711, and is axially connected to the hub cylindrical portion 72. In this embodiment, there are multiple connecting portions 714, and they are lined up in the circumferential direction along the radially outer end of the disk portion 711.

[0039] The hub cylindrical portion 72 extends in the axial direction, surrounding the annular gear 67 and the second contact portion 712. As described above, the hub 7 has the hub cylindrical portion 72. The end of the hub cylindrical portion 72 on one axial direction Da is connected to the radially outer end of the disk portion 711. In other words, the end of the hub cylindrical portion 72 on one axial direction Da is covered by the disk hub 71. The hub cylindrical portion 72 accommodates the rotor 3, the stator 4, the stator holder 5, and the reduction gear 6 inside.

[0040] The hub cylindrical portion 72 has a cylindrical portion 721 , flange portions 7221 and 7222 , a bottom plate 724 , a bearing holder 725 , and a bearing 7251 .

[0041] The cylindrical portion 721 is cylindrical and surrounds the rotor 3, the stator 4, the stator holder 5, and the reduction gear 6, and extends in the axial direction. An end portion of the cylindrical portion 721 on one axial direction Da side is connected to the connecting portion 714. As a result, an end portion of the hub cylindrical portion 72 on one axial direction Da side is connected to the disc hub 71.

[0042] The flange portions 7221, 7222 are disposed on the radially outer surface of the cylindrical portion 721 and extend circumferentially, spreading radially outward from the cylindrical portion 721. In this embodiment, the flange portions 7221, 7222 are annular and surround the cylindrical portion 721. The flange portion 7221 is disposed on one axial side Da of the cylindrical portion 721. The flange portion 7222 is disposed on the other axial side Db of the cylindrical portion 721.

[0043] The rib 723 protrudes radially inward from the radially inner end of the hub tubular portion 72 (specifically, the tubular portion 721) and extends circumferentially. As described above, the hub tubular portion 72 has the rib 723. The rib 723 is positioned further in the axial direction Db than the annular gear 67 and overlaps with the radially outer end of the annular gear 67 (particularly the gear tubular portion 671) when viewed from the axial direction. Specifically, the rib 723 is positioned further in the axial direction Db than the flange portion 672 and is in contact with the flange portion 672 in the axial direction. In other words, the radially inner end of the rib 723 is positioned radially inward from the radially outer end of the annular gear 67 (particularly the gear tubular portion 671). In this way, the rib 723 can prevent the annular gear 67 from moving toward the axial direction Db.

[0044] In this embodiment, as shown in FIG. 3, there are multiple ribs 723 arranged circumferentially with gaps between them. This prevents the ribs 723 from interfering with the attachment of components located on the other axial direction Db side of the ribs 723 when assembling the motor 1. For example, when the reduction gear 6 is attached after the hub cylinder portion 72 is attached to the motor 1, the planetary gear 65 passes through the gaps to avoid contact with the ribs 723. However, the above examples do not exclude configurations in which there is a single rib 723 or where there are no gaps between the multiple ribs 723 in the circumferential direction. For example, the rib 723 may be annular and surround the central axis CX.

[0045] The bottom plate 724 extends radially inward from the end portion on the other axial direction Db side of the cylindrical portion 721. The bottom plate 724 has a disk shape that surrounds the axle 113, and is disposed on the other axial direction Db side of the stator holder 5.

[0046] The bearing holder 725 is cylindrical and extends in the axial direction from the radially inner end of the bottom plate 724. The axle 113 is inserted into the bearing holder 725. A bearing 7251 is disposed on the radially inner surface of the bearing holder 725. The bearing holder 725 rotatably supports the axle 113 via the bearing 7251.

[0047] In this embodiment, the cylindrical portion 721, the flange portions 7221 and 7222, the rib 723, the bottom plate 724, and the bearing holder 725 are integral with each other. However, this is not limiting, and at least some of these may be separate from the others.

[0048] <1-8. First Contact Portion 673 and Second Contact Portion 712> Next, the first contact portion 673 and the second contact portion 712 will be described in detail with reference to Fig. 1 and Fig. 3 to Fig. 6. Fig. 6 is a diagram showing the connection structure between the first contact portion 673 and the second contact portion 712. Note that Fig. 6 shows the connection structure between the first contact portion 673 and the second contact portion 712 as viewed from the radially outer side toward the radially inner side, and corresponds to portion VI surrounded by a dashed line in Fig. 5.

[0049] In the present embodiment, the first contact portion 673 of the annular gear 67 has a plurality of first recesses 6731 and a plurality of first protrusions 6732. The first recesses 6731 and the first protrusions 6732 are disposed on an end face of the flange portion 672 on one axial direction Da side. The first recesses 6731 are recessed toward the other axial direction Db and extend radially. Specifically, the first recesses 6731 are recessed from one axial end of the flange portion 672 toward the other axial direction Db and extend radially inward from the radial outer end of the flange portion 672. In other words, the first recesses 6731 are spaces disposed between the first protrusions 6732 adjacent to each other in the circumferential direction. The first protrusions 6732 protrude toward the one axial direction Da and extend radially. In other words, the first protrusions 6732 are parts of the flange portion 672 disposed between the first recesses 6731 adjacent to each other in the circumferential direction.

[0050] Furthermore, in the disc hub 71 according to the present embodiment, the second contact portion 712 has a plurality of second recesses 7121 and a plurality of second protrusions 7122. The second recesses 7121 and the second protrusions 7122 are disposed in a radially outer region of the end face of the disc portion 711 on the other axial direction Db side. The second recesses 7121 are recessed in the one axial direction Da and extend in the radial direction. In other words, the second recesses 7121 are spaces disposed between the second protrusions 7122 that are adjacent to each other in the circumferential direction. The second protrusions 7122 protrude in the other axial direction Db and extend in the radial direction. In other words, the second protrusions 7122 are parts of the disc portion 711 that are disposed between the second recesses 7121 that are adjacent to each other in the circumferential direction.

[0051] The first protrusions 6732 are disposed inside the second recesses 7121, in other words, disposed between the second protrusions 7122 that are adjacent in the circumferential direction. When the annular gear 67 rotates in one circumferential direction, one circumferential end face of the first protrusions 6732 contacts the inner surface of the second recesses 7121 that faces the other circumferential direction, in other words, contacts the other circumferential end face of the second protrusions 7122.

[0052] The second protrusions 7122 are disposed inside the first recesses 6731, in other words, disposed between the circumferentially adjacent first protrusions 6732. When the annular gear 67 rotates in one circumferential direction, one circumferential end face of the second protrusions 7122 contacts the inner surface of the first recesses 6731 facing the other circumferential direction, in other words, contacts the other circumferential end face of the first protrusions 6732.

[0053] An adhesive 83 may be filled between the first convex portion 6732 and the second concave portion 7121 or the second convex portion 7122 (in other words, between the first concave portion 6731 or the first convex portion 6732 and the second convex portion 7122). That is, the adhesive 83 may be filled between the first contact portion 673 and the second contact portion 712. In this case, the adhesive 83 can firmly fix the first contact portion 673 and the second contact portion 712. Therefore, the annular gear 67 can be more firmly connected to the disc hub 71. Therefore, the torque transmission efficiency of the annular gear 67 to the disc hub 71 can be further improved. However, this example does not exclude a configuration in which the adhesive 83 is not filled between the first contact portion 673 and the second contact portion 712.

[0054] Note that the examples of this embodiment do not exclude a configuration in which at least one of the first convex portion 6732 and the first concave portion 6731 is singular, a configuration in which the first contact portion 673 has only one of the first convex portion 6732 and the first concave portion 6731, etc. Furthermore, the examples of this embodiment do not exclude a configuration in which at least one of the second convex portion 7122 and the second concave portion 7121 is singular, a configuration in which the second contact portion 712 has only one of the second convex portion 7122 and the second concave portion 7121, etc.

[0055] In the following, either the first recess 6731 or the second recess 7121 may be referred to as the "recess 81." In addition, of the first protrusion 6732 and the second protrusion 7122, the one that is arranged inside the recess 81 may be referred to as the "protrusion 82."

[0056] At the connection portion between the disc hub 71 and the annular gear 67, one of the first contact portion 673 and the second contact portion 712 has a recess 81 recessed in the axial direction. Note that the recess 81 is a first recess 6731 when the one is the first contact portion 673, and a second recess 7121 when the other is the second contact portion 712. The other of the first contact portion 673 and the second contact portion 712 has a protrusion 82. The protrusion 82 protrudes in the axial direction and is disposed inside the recess 81. Note that the protrusion 82 is a second protrusion 7122 when the other is the second contact portion 712, and a first protrusion 6732 when the other is the first contact portion 673. Due to the engagement between the recess 81 and the protrusion 82, when the annular gear 67 rotates, the inner surface of the recess 81 facing one circumferential direction comes into contact with the other circumferential end face of the protrusion 82. This allows the rotation of the annular gear 67 in one circumferential direction to be transmitted to the disk hub 71 .

[0057] Preferably, the minimum circumferential width of the recess 81 is wider than the maximum circumferential width of the protrusion 82. For example, the minimum circumferential width W1a of the first recess 6731 is wider than the maximum circumferential width W2b of the second protrusion 7122. Furthermore, the minimum circumferential width W2a of the second recess 7121 is wider than the maximum circumferential width W1b of the first protrusion 6732. This makes it easier for the protrusion 82 to fit into the recess 81 compared to a configuration in which the maximum circumferential width of the protrusion 82 is the same as or wider than the minimum circumferential width of the recess 81. This makes it easier to attach the disc hub 71 to the annular gear 67. Furthermore, the protrusion 82 can be more smoothly fitted into the recess 81. For example, this prevents the protrusion 82 from getting caught on the inner surface of the recess 81. Alternatively, this prevents sliding between the inner surface of the recess 81 facing the circumferential direction and the circumferential end surface of the protrusion 82. Therefore, wear of the recessed portion 81 and the protruding portion 82 during fitting can be prevented.

[0058] Preferably, when the annular gear 67 rotates in one circumferential direction, in at least one first recess 6731, the entire area of ​​the inner surface of the first recess 6731 facing in one circumferential direction contacts the other circumferential end face of the second protrusion 7122. Furthermore, in at least one first protrusion 6732, the entire area of ​​the one circumferential end face of the first protrusion 6732 contacts the inner surface of the second recess 7121 facing in the other circumferential direction (or the other circumferential end face of the second protrusion 7122). That is, in at least one first contact portion 673, the entire area of ​​the circumferential end face of the first contact portion 673 facing the second contact portion 712 in the circumferential direction contacts the second contact portion 712. By increasing the contact area of ​​the first contact portion 673 with the second contact portion 712, the efficiency of torque transmission of the annular gear 67 to the disc hub 71 can be improved. However, this example does not exclude a configuration in which, in all first contact portions 673, the entire circumferential end surface of the first contact portion 673 facing the second contact portion 712 in the circumferential direction does not come into contact with the second contact portion 712.

[0059] Preferably, an inner surface of the second recess 7121 facing one circumferential direction is wider than the other circumferential end face of the first protrusion 6732. Furthermore, the one circumferential end face of the second protrusion 7122 is wider than an inner surface of the first recess 6731 facing the other circumferential direction (or the other circumferential end face of the first protrusion 6732). That is, the circumferential end face of the second contact portion 712 facing the first contact portion 673 is wider than the circumferential end face of the first contact portion 673 facing the second contact portion 712. For example, the radial widths d2a, d2b of the second recess 7121 or the second protrusion 7122 may be wider than the radial width d1 of the first recess 6731 or the first protrusion 6732. Furthermore, the axial width h2 of the second recess 7121 or the second protrusion 7122 may be wider than the axial width h1 of the first recess 6731 or the first protrusion 6732. This allows the area of ​​the circumferential end face of the second contact portion 712 of the disc hub 71 to be larger than the contact area of ​​the contact portion between the first contact portion 673 and the second contact portion 712. This allows at least one of the radial widths d2a, d2b and the axial width h2 of the circumferential end face of the second contact portion 712 to be larger than the contact area of ​​the contact portion. Therefore, even if there is an error in the dimension or position of the second contact portion 712, a reduction in the contact area can be prevented. This prevents a reduction in the torque transmission efficiency of the annular gear 67 with respect to the disc hub 71. However, the above example does not exclude a configuration in which the area of ​​the circumferential end face of the second contact portion 712 on the first contact portion 673 side is equal to or smaller than the area of ​​the circumferential end face of the first contact portion 673 on the second contact portion 712 side.

[0060] One of the first recessed portions 6731 and the second protruding portions 7122 are arranged at equal intervals in the circumferential direction. Preferably, both the first recessed portions 6731 and the second protruding portions 7122 are arranged at equal intervals in the circumferential direction. In other words, one of the first protruding portions 6732 and the second recessed portions 7121 are arranged at equal intervals in the circumferential direction. Preferably, both the first protruding portions 6732 and the second recessed portions 7121 are arranged at equal intervals in the circumferential direction. In other words, at least one of the first contact portions 673 and the second contact portions 712 is arranged at equal intervals in the circumferential direction. This makes it possible to suppress or prevent circumferential imbalance in the torque acting between the annular gear 67 and the disc hub 71 during rotation of the annular gear 67. However, the above example does not exclude a configuration in which both the plurality of first contact portions 673 and the plurality of second contact portions 712 are not arranged at equal intervals in the circumferential direction.

[0061] In the present embodiment, the first protrusion 6732 has a first cutout 6733. The first cutout 6733 is disposed at the tip of the first protrusion 6732, both between the end face on one axial direction Da side and one circumferential end face and between the end face on one axial direction Da side and the other circumferential end face. Alternatively, the first cutout 6733 may be disposed only between the end face on one axial direction Da side and one circumferential end face or between the end face on one axial direction Da side and the other circumferential end face. The first cutout 6733 is a portion where a curved surface or a flat surface is disposed between the end face on one axial direction Da side of the first protrusion 6732 and the circumferential end face. For example, the first cutout 6733 may be a so-called R-chamfered portion or a so-called C-chamfered portion. In R-chamfering, a curved surface is disposed between the end face on one axial side Da and the circumferential end face. This curved surface protrudes in the axial direction Da and the circumferential direction when viewed from the radial direction, and extends radially. In C-chamfering, the corners between the end face on one axial side Da and the circumferential end face are cut off diagonally, and a flat surface is disposed that extends radially and intersects the axial direction diagonally.

[0062] The second protrusion 7122 also has a second cutout 7123. The second cutout 7123 is disposed at the tip of the second protrusion 7122, between the end face on the other axial direction Db side and one circumferential end face, and between the end face on the other axial direction Db side and the other circumferential end face. Alternatively, the second cutout 7123 may be disposed only between the end face on the other axial direction Db side and one circumferential end face, or between the end face on the other axial direction Db side and the other circumferential end face. The second cutout 7123 is a portion in which a curved surface or a flat surface is disposed between the end face on the other axial direction Db side of the second protrusion 7122 and the circumferential end face. For example, the second cutout 7123 may be a so-called R-chamfered portion or a so-called C-chamfered portion. In the R-chamfered portion, a curved surface is disposed between the end face on the other axial direction Db side and the circumferential end face. This curved surface protrudes in the axial direction Db and the circumferential direction as viewed from the radial direction, and extends in the radial direction. In the C-chamfering, the corner between the end face on the axial direction Db side and the circumferential end face is cut off obliquely, and a flat surface is disposed that extends in the radial direction and obliquely intersects the axial direction.

[0063] In the following description, at least one of the first cutout portion 6733 and the second cutout portion 7123 may be referred to as the "cutout portion 84."

[0064] Without being limited to the above example, either the first notch portion 6733 or the second notch portion 7123 may be omitted. That is, at least one of the first contact portion 673 and the second contact portion 712 may have a notch portion 84 disposed between the axial end face and the circumferential end face. For example, the notch portion 84 is disposed between the axial end face and the circumferential end face at the tip of the convex portion 82. Due to the arrangement of the notch portion 84, when at least one of the first contact portion 673 and the second contact portion 712 is moved axially to contact the other in the circumferential direction, the corner between the axial end face and the circumferential end face does not hit the other, making it easier for the two to contact each other. For example, when the recessed portion 81 and the protruding portion 82 are fitted together, disposing the notch portion at the tip of the protruding portion 82 makes it easier to position the protruding portion 82 inside the recessed portion 81. Furthermore, as will be described later, when bonding the first contact portion 673 and the second contact portion 712 with adhesive 83, a space for collecting the adhesive 83 can be formed in the cutout portion 84. This makes it difficult for the adhesive 83 to spill out from between the two, for example.

[0065] Preferably, the radial width d2b of the second protrusion 7122 (or the second recess 7121) at its portion on the other axial side Db is narrower than the radial width d2a of its portion on the one axial side Da. In other words, the radial width d2b of the second contact portion 712 at its portion on the other axial side Db is narrower than the radial width d2a of the second contact portion 712 at its portion on the one axial side Da. This makes the radial width d2b of the second contact portion 712 on the annular gear 67 side narrower than the radial width d2a of the second contact portion 712 on the disk portion 711 side. This makes it easier to position the second contact portion 712 inside the hub cylindrical portion 72 (i.e., the cylindrical portion 721). This makes it easier to connect the hub cylindrical portion 72 to the disk hub 71. However, this example does not exclude a configuration in which the radial width d2b of the second contact portion 712 on the annular gear 67 side is equal to or greater than the radial width d2a of the second contact portion 712 on the disk portion 711 side.

[0066] Furthermore, in the present embodiment, in at least one first protrusion 6732, the end portion of the first protrusion 6732 on the one axial direction Da side axially contacts the bottom surface of the second recess 7121 facing the other axial direction Db. However, this is not limited to this example, and in at least one second protrusion 7122, the end portion of the second protrusion 7122 on the other axial direction Db side may also contact the bottom surface of the first recess 6731 facing the one axial direction Da. In other words, the axial end portion of either the first contact portion 673 or the second contact portion 712 contacts the member having the other of the first contact portion 673 and the second contact portion 712 in the axial direction, of the annular gear 67 or the disc hub 71. Due to the above-described axial contact, the axial position of one of the annular gear 67 and the disc hub 71 relative to the other can be easily determined. However, the above example does not exclude a configuration in which none of the first contact portions 673 contact the disc hub 71 in the axial direction, nor does it exclude a configuration in which none of the second contact portions 712 contact the annular gear 67 in the axial direction. Furthermore, the above example does not exclude a configuration in which, in at least one first protrusion 6732, an end portion on one axial direction Da of the first protrusion 6732 axially contacts a bottom surface facing the other axial direction Db of the second recess 7121, and, in at least one second protrusion 7122, an end portion on the other axial direction Db of the second protrusion 7122 axially contacts a bottom surface facing the one axial direction Da of the first recess 6731.

[0067] <2. Modifications of the embodiment> Next, a modified example of the embodiment will be described with reference to Fig. 7. Fig. 7 is an external view of an assembly of a disk hub 71 and an annular gear 67 according to the modified example. In Fig. 7, the assembly is viewed from the radial direction Dd. In the modified example, the radial direction is designated by the symbol "Dd" and the circumferential direction is designated by the symbol "Dr." Furthermore, the radially inward direction is designated by the symbol "Di" and the radially outward direction is designated by the symbol "Do."

[0068] The following describes the configuration of the modified example that differs from the above-described embodiment. The same components as those in the above-described embodiment are given the same reference numerals, and their description may be omitted. Note that at least some of the configuration of the modified example can be implemented in any combination with the configuration of the above-described embodiment, provided that no particular contradiction occurs.

[0069] In a modified example, the ring gear 67 further includes a flange recess 674. The flange recess 674 is disposed at the radially outer end of the flange portion 672 and is recessed radially inward Di. Fig. 8 is a side view of the ring gear 67 showing an example configuration of the flange recess 674. Fig. 8 is an enlarged view of a portion VIII surrounded by a dashed line in Fig. 7.

[0070] 8, the flange recess 674 extends from a bottom surface 67311 facing one axial direction Da of the first recess 6731 toward the other axial direction Db. In the modified example, the first recess 6731 is an example of a "gear recess" of the present invention. The flange recess 674 extends radially inward Di from the radially outer end of the flange portion 672. The arrangement of the flange recess 674 allows for a reduction in the material of the flange portion 672, thereby reducing the weight of the annular gear 67.

[0071] The flange recess 674 overlaps with the rib 723 of the hub cylindrical portion 72 in the axial direction. FIG. 9 is a cross-sectional view showing the positional relationship between the flange recess 674 and the rib 723. FIG. 9 shows the cross-sectional structure as viewed from the circumferential direction Dr, corresponding to the portion IX surrounded by the dashed line in FIG. 1. As shown in FIG. 9 and other figures, the thin portion 6721 of the flange portion 672 overlaps with and contacts the rib 723 in the axial direction. The thin portion 6721 is a portion between an inner surface 6741 of the flange portion 672 facing one axial direction Da of the flange recess 674 and the other axial end surface of the flange portion 672. With regard to the thickness of the flange portion 672, the axial thickness of the thin portion 6721 where the flange recess 674 is disposed is the thinnest in the circumferential direction of the flange portion 672. Therefore, the thin portion 6721 is more susceptible to elastic deformation than other portions of the flange portion 672 in the circumferential direction (in other words, portions other than the thin portion 6721). The rib 723 contacts this portion in the axial direction. By assembling the motor 1 in a state in which the thin portion 6721 is elastically deformed in one axial direction Da by the rib 723, it is possible to maintain a state in which a force toward one axial direction Da acts on the ring gear 67. Therefore, movement of the ring gear 67 in the other axial direction Db can be more effectively suppressed.

[0072] As described above, the material of the ring gear 67 is resin, which allows the thin portion 6721 of the flange portion 672 to be elastically deformed to a greater extent than when the ring gear 67 is made of metal, for example.

[0073] When viewed from the axial direction, the thin portion 6721 where the flange recess 674 is disposed overlaps the entire area of ​​the rib 723 in the circumferential direction Dr. For example, as shown in FIG. 8 , one circumferential end of the rib 723 is disposed such that the inner surface 6741 facing one axial direction Da is at the same circumferential position as the one circumferential end of the flange recess 674 that faces the rib 723 in the axial direction, or further circumferentially than the one circumferential end of the flange recess 674. The other circumferential end of the rib 723 is disposed such that the inner surface 6741 facing one axial direction Da is at the same circumferential position as the other circumferential end of the flange recess 674 that faces the rib 723 in the axial direction, or further circumferentially than the other circumferential end of the flange recess 674. This allows the rib 723 to contact only the thin portion 6721 of the flange portion 672 where the flange recess 674 is disposed. Because the rib 723 does not contact other portions of the flange portion 672 in the circumferential direction Dr, the thin portion 6721 can be significantly elastically deformed.

[0074] The radial width W3 of the flange recess 674 is wider than the radial width W4 of the rib 723 (see FIG. 9). The radial width W3 is, for example, the radial width of the inner surface 6741 of the flange recess 674 facing one axial direction Da. By making W3 > W4, the thin portion 6721 of the flange portion 672 where the flange recess 674 is disposed can be made wider. Therefore, this thin portion 6721 can be made to have a greater elastic deformation. Furthermore, since the material of the flange portion 672 can be made less, the weight of the ring gear 67 can be made lighter. However, this example does not exclude a configuration where W3 = W4.

[0075] Preferably, the distance W5 between the inner surface 6741 of the flange recess 674 facing one axial direction Da and the other axial end surface of the flange portion 672 is equal to or less than the axial width W6 of the flange recess 674 (see FIGS. 8 and 9). The distance W5 is the axial thickness of the thin portion 6721 of the flange portion 672. The axial width W6 is the distance between one axial end and the other axial end of the flange recess 674. By making W5≦W6, the thin portion 6721 of the flange portion 672 where the flange recess 674 is disposed can be made thinner. Therefore, the thin portion 6721 can be elastically deformed to a greater extent. However, this example does not exclude a configuration in which W5>W6.

[0076] Preferably, the axial width W7 of the rib 723 (i.e., the axial thickness) is greater than the distance W5 between the inner surface 6741 facing the one axial direction Da of the flange recess 674 and the other axial end face of the flange portion 672 (see FIGS. 8 and 9). By making W7 > W5, the axial thickness of the rib 723 is increased, thereby preventing deformation of the rib 723. Therefore, movement of the ring gear 67 toward the other axial direction Db can be more effectively suppressed. However, this example does not exclude a configuration where W7 ≦ W5.

[0077] 7 and 8, the thin portion 6721 in which the flange recess 674 is disposed is connected to other portions of the flange portion 672 in the circumferential direction Dr. However, this is not limited to this example, and in the flange portion 672, at least one end of the thin portion 6721 in the circumferential direction Dr does not have to be connected to other portions of the flange portion 672 in the circumferential direction Dr, and may be separated from the other portions in the circumferential direction Dr. Fig. 10 is a side view of the annular gear 67 showing another example of the configuration of the flange recess 674.

[0078] 10, the annular gear 67 further includes a hole 675. The hole 675 is disposed on at least one circumferential end of an inner surface 6741 facing one axial direction Da of the flange recess 674, and axially penetrates the flange portion 672. The hole 675 extends radially inward Di from the radially outer end of the flange portion 672.

[0079] 10 , the hole portion 675 includes a first hole portion 6751 and a second hole portion 6752. In other words, the annular gear 67 is equipped with the first hole portion 6751 and the second hole portion 6752. The first hole portion 6751 is disposed at one circumferential end portion of the inner surface 6741 facing one axial direction Da of the flange recessed portion 674. The second hole portion 6752 is disposed at the other circumferential end portion of the inner surface 6741 facing one axial direction Da of the flange recessed portion 674. The first hole portion 6751 and the second hole portion 6752 axially penetrate the thin portion 6721 of the flange portion 672 and extend radially inward Di from the radially outer end portion of the flange portion 672.

[0080] 10 , the hole portion 675 includes both the first hole portion 6751 and the second hole portion 6752. In other words, in the flange portion 672, both circumferential ends of the thin portion 6721 are not connected to other portions of the flange portion 672 in the circumferential direction. However, without being limited to this example, the hole portion 675 may include only either the first hole portion 6751 or the second hole portion 6752. In other words, in the flange portion 672, one circumferential end of the thin portion 6721 may be connected to other portions of the flange portion 672 in the circumferential direction Dr, while the other circumferential end of the thin portion 6721 may not be connected to other portions of the flange portion 672 in the circumferential direction Dr.

[0081] This further reduces the weight of the annular gear 67. Furthermore, at least one end in the circumferential direction Dr of the thin portion 6721, where the flange recess 674 of the flange portion 672 is arranged, is separated from other portions in the circumferential direction Dr by the arrangement of the hole 675, and becomes a free end. Therefore, the thin portion 6721 can be elastically deformed to a greater extent.

[0082] In addition, the annular gear 67 further includes a recess 676. The recess 676 is disposed in the flange portion 672 at a different circumferential position from the flange recess 674. For example, the recess 676 overlaps with the first protrusion 6732 of the annular gear 67 in the axial direction. The recess 676 is recessed radially inward and extends from the other axial end face of the flange portion 672 to one axial direction Da. A plurality of recesses 676 may be disposed in the circumferential direction Dr as shown in FIG. 7, or a single recess 676 may be disposed. The arrangement of the recess 676 allows for further reduction in the material of the flange portion 672, thereby further reducing the weight of the annular gear 67.

[0083] <3. Vehicle 100> In this embodiment, the motor 1 is a so-called hub motor, and is mounted on a vehicle 100. Fig. 11 is a schematic diagram of the vehicle 100 mounted with the motor 1. The vehicle 100 in Fig. 11 is an electrically assisted bicycle. However, the example of this embodiment does not exclude a configuration in which the motor 1 is mounted on a vehicle 100 other than an electrically assisted bicycle.

[0084] 11, vehicle 100 includes motor 1. In vehicle 100, rotation of rotor 3 can be transmitted from reduction gear 6 to hub 7 without disposing a connecting portion on motor 1 that axially connects an annular gear 67 (described later) of reduction gear 6 and a disc hub 71.

[0085] The vehicle 100 further includes a body 110 , front wheels 120 , rear wheels 130 , a handlebar 140 , and a battery 150 .

[0086] The body 110 includes a fork 111 and axles 112 and 113 for a front wheel 120. The fork 111 supports the front wheel 120 via the axles 112 and 113. One ends of the axles 112 and 113 are connected to a motor 1 for the front wheel 120. The other ends of the axles 112 and 113 are supported at the tip of the fork 111 so as not to be rotatable.

[0087] A front wheel 120 and a handlebar 140 are attached to the front of the vehicle body 110. The front wheel 120 has a motor 1, a plurality of spokes 121, a rim 122, and a tire 123. The spokes 121 are arranged in the circumferential direction and support the rim 122 relative to the motor 1. The rim 122 is an annular member that surrounds the central axis CX and the motor 1. Radial inner ends of the spokes 121 are fixed to the motor 1 (more specifically, flange portions 7221, 7222). Radial outer ends of the spokes 121 are fixed to the radial inner end of the rim 122. The tire 123 is attached to the radial outer end of the rim 122.

[0088] A rear wheel 130 is rotatably attached to the rear of the vehicle body 110. The rear wheel 130 rotates in response to the force applied to the pedals 114 by the user.

[0089] A battery 150 is also attached to the vehicle body 110. The battery 150 is a chargeable and dischargeable battery, and supplies power to the motor 1.

[0090] In the vehicle 100, the tire 123 of the front wheel 120 rotates about the central axis CX in response to the rotation of the rear wheel 130. The torque generated around the central axis CX is transmitted to the motor 1 via the rim 122 and the spokes 121. This torque is transmitted to the rotor 3 via the hub 7, the annular gear 67, the reduction gear 6, and the shaft 2, causing the rotor 3 to rotate about the central axis CX. The motor 1 has a sensor (not shown) that detects the rotation of at least one of the annular gear 67 and the hub 7, such as the shaft 2, the rotor 3, the gears 65 and 66 of the reduction gear 6, and the planetary carrier 64, and rotates the rotor 3 in one or the other circumferential direction about the central axis CX as needed. The torque of the rotor 3 is added to the torque for propelling the vehicle 100. In other words, the motor 1 supplements the torque required for propelling the vehicle 100 as needed.

[0091] <4.Other> The embodiments of the present invention have been described above. However, the scope of the present invention is not limited to the above-described embodiments. The present invention can be implemented by adding various modifications to the above-described embodiments without departing from the spirit of the invention. Furthermore, the matters described in the above-described embodiments can be combined in any appropriate manner as long as no contradiction occurs. [Industrial Applicability]

[0092] The present invention is useful, for example, in devices that transmit the rotation of a rotor to a rotatable member. [Explanation of symbols]

[0093] 1 motor, 2 shaft, 3 rotor, 31 one-way clutch, 32 rotor core, 33 magnet, 4 stator, 41 stator core, 42 insulator, 43 coil portion, 5 stator holder, 51 bearing holder, 511 bearing, 52 bracket, 521 support portion, 53 holder portion, 54 substrate, 6 reduction gear, 61 base, 611 bearing holder, 6 111... bearing, 612... base plate portion, 613... base cylinder portion, 62... sun gear, 63... planet shaft, 64... planet carrier, 65... planet gear, 66... ​​pinion gear, 67... ring gear, 671... gear cylinder portion, 672... flange portion, 6721... thin portion, 673... first contact portion, 6731... first recessed portion, 67311... bottom surface, 6732... first protruding portion, 6733... first cutout portion, 674... flange recessed portion, 6741... Inner surface, 675...hole portion, 6751...first hole portion, 6752...second hole portion, 676...recessed portion, 7...hub, 71...disk hub, 711...disk portion, 712...second contact portion, 7121...second recessed portion, 7122...second protruding portion, 7123...second notched portion, 713...bearing holder, 7131...bearing, 714...connecting portion, 72...hub cylindrical portion, 721...cylindrical portion, 7221, 7222...flange portion, 723...rib, 724...bottom plate , 725···Bearing holder, 7251···Bearing, 81···Concave portion, 82···Convex portion, 83···Adhesive, 84···Notched portion, 100···Vehicle, 110···Vehicle body, 111···Fork, 112, 113···Axle, 114···Pedal, 120···Front wheel, 121···Spoke, 122···Rim, 123···Tire, 130···Rear wheel, 140···Handle, 150···Battery, CX···Center axis, Da···One axial direction, Db···One axial direction

Claims

1. a shaft extending along an axially extending central axis; a rotor rotatable together with the shaft about the central axis; a stator radially opposed to the rotor; a reduction gear connected to the shaft; a hub rotatable about the central axis; Equipped with the reduction gear has an annular gear that surrounds the central shaft and is rotatable about the central shaft; the annular gear has a first contact portion; The hub has a disk hub surrounding the central axis, The disc hub is a disk portion disposed on one side of the annular gear in the axial direction and surrounding the central axis and extending in the radial direction; a second contact portion disposed on the other axial side of the disk portion and capable of coming into contact with the first contact portion in a circumferential direction; and the first contact portion has a first protrusion that protrudes in one axial direction, the second contact portion has a plurality of second protrusions disposed on an end surface on the other axial side of the disk portion and protruding in the other axial direction, The first protrusions are disposed between the second protrusions adjacent to each other in the circumferential direction.

2. A shaft extending along a central axis extending in an axial direction; a rotor rotatable together with the shaft about the central axis; a stator radially opposed to the rotor; a reduction gear connected to the shaft; a hub rotatable about the central axis; Equipped with the reduction gear has an annular gear that surrounds the central shaft and is rotatable about the central shaft; the annular gear has a first contact portion; The hub has a disk hub surrounding the central axis, The disc hub is a disk portion disposed on one side of the annular gear in the axial direction and surrounding the central axis and extending in the radial direction; a second contact portion disposed on the other axial side of the disk portion and capable of coming into contact with the first contact portion in a circumferential direction; and one of the first contact portion and the second contact portion has a recess recessed in the axial direction; The other of the first contact portion and the second contact portion has a protrusion that protrudes in the axial direction and is disposed inside the recess.

3. The motor according to claim 2 , wherein a minimum circumferential width of the recessed portion is greater than a maximum circumferential width of the protruding portion.

4. A shaft extending along a central axis extending in an axial direction; a rotor rotatable together with the shaft about the central axis; a stator radially opposed to the rotor; a reduction gear connected to the shaft; a hub rotatable about the central axis; Equipped with the reduction gear has an annular gear that surrounds the central shaft and is rotatable about the central shaft; the annular gear has a first contact portion; The hub has a disk hub surrounding the central axis, The disc hub is a disk portion disposed on one side of the annular gear in the axial direction and surrounding the central axis and extending in the radial direction; a second contact portion disposed on the other axial side of the disk portion and capable of coming into contact with the first contact portion in a circumferential direction; and At least one of the first contact portion and the second contact portion has a notch portion disposed between an axial end surface and a circumferential end surface.

5. A shaft extending along a central axis extending in an axial direction; a rotor rotatable together with the shaft about the central axis; a stator radially opposed to the rotor; a reduction gear connected to the shaft; a hub rotatable about the central axis; Equipped with the reduction gear has an annular gear that surrounds the central shaft and is rotatable about the central shaft; the annular gear has a first contact portion; The hub has a disk hub surrounding the central axis, The disc hub is a disk portion disposed on one side of the annular gear in the axial direction and surrounding the central axis and extending in the radial direction; a second contact portion disposed on the other axial side of the disk portion and capable of coming into contact with the first contact portion in a circumferential direction; and A motor, wherein in at least one of the first contact portions, an entire area of ​​a circumferential end face of the first contact portion facing the second contact portion in the circumferential direction is in contact with the second contact portion.

6. A shaft extending along a central axis extending in an axial direction; a rotor rotatable together with the shaft about the central axis; a stator radially opposed to the rotor; a reduction gear connected to the shaft; a hub rotatable about the central axis; Equipped with the reduction gear has an annular gear that surrounds the central shaft and is rotatable about the central shaft; the annular gear has a first contact portion; The hub has a disk hub surrounding the central axis, The disc hub is a disk portion disposed on one side of the annular gear in the axial direction and surrounding the central axis and extending in the radial direction; a second contact portion disposed on the other axial side of the disk portion and capable of coming into contact with the first contact portion in a circumferential direction; and a circumferential end surface of the second contact portion on the side of the first contact portion is wider than a circumferential end surface of the first contact portion on the side of the second contact portion.

7. A shaft extending along a central axis extending in an axial direction; a rotor rotatable together with the shaft about the central axis; a stator radially opposed to the rotor; a reduction gear connected to the shaft; a hub rotatable about the central axis; Equipped with the reduction gear has an annular gear that surrounds the central shaft and is rotatable about the central shaft; the annular gear has a first contact portion; The hub has a disk hub surrounding the central axis, The disc hub is a disk portion disposed on one side of the annular gear in the axial direction and surrounding the central axis and extending in the radial direction; a second contact portion disposed on the other axial side of the disk portion and capable of coming into contact with the first contact portion in a circumferential direction; and The annular gear comprises: a gear cylinder portion extending in the axial direction; a flange portion that spreads radially outward from the gear cylindrical portion and extends in a circumferential direction; a flange recessed portion disposed at a radially outer end of the flange portion and recessed radially inward; a motor further comprising:

8. A shaft extending along a central axis extending in an axial direction; a rotor rotatable together with the shaft about the central axis; a stator radially opposed to the rotor; a reduction gear connected to the shaft; a hub rotatable about the central axis; Equipped with the reduction gear has an annular gear that surrounds the central shaft and is rotatable about the central shaft; the annular gear has a first contact portion; The hub has a disk hub surrounding the central axis, The disc hub is a disk portion disposed on one side of the annular gear in the axial direction and surrounding the central axis and extending in the radial direction; a second contact portion disposed on the other axial side of the disk portion and capable of coming into contact with the first contact portion in a circumferential direction; and the hub further includes a hub cylindrical portion that extends in the axial direction and surrounds the annular gear and the second contact portion, one axial end of the hub cylindrical portion is connected to a radially outer end of the disk portion, A motor, wherein the radial width of a portion of the second contact portion on the other axial side is narrower than the radial width of a portion of the second contact portion on one axial side.

9. the hub cylindrical portion has a rib that projects radially inward and extends circumferentially at a radially inner end of the hub cylindrical portion, The motor according to claim 8 , wherein the rib is disposed on the other side of the ring gear in the axial direction and overlaps with a radially outer end of the ring gear when viewed from the axial direction.

10. The motor according to claim 9 , wherein the ribs are a plurality of ribs arranged in the circumferential direction with gaps therebetween.

11. The annular gear comprises: a gear cylinder portion extending in the axial direction; a flange portion that spreads radially outward from the gear cylindrical portion and extends in a circumferential direction; a flange recessed portion disposed at a radially outer end of the flange portion and recessed radially inward; and the first contact portion has a gear recess that is recessed from one axial end portion of the flange portion toward the other axial end portion and extends radially inward from a radially outer end portion of the flange portion, the flange recess extends from a bottom surface of the gear recess facing one axial direction to the other axial direction, the rib is disposed on the other side of the flange portion in the axial direction and is in contact with the flange portion in the axial direction; The motor according to claim 9 or 10, wherein the flange recess overlaps with the rib in the axial direction.

12. one circumferential end of the rib is disposed at the same circumferential position as one circumferential end of the flange recessed portion, whose inner surface facing one axial direction faces the rib in the axial direction, or at an opposite circumferential position from the one circumferential end of the flange recessed portion, 12. The motor according to claim 11, wherein the other circumferential end of the rib is positioned at the same circumferential position as the other circumferential end of the flange recess, whose inner surface facing one axial direction is axially opposed to the rib, or further circumferentially than the other circumferential end of the flange recess.

13. 13. The motor according to claim 11, wherein a distance between an inner surface of the flange recess facing one axial direction and the other axial end face of the flange is equal to or less than an axial width of the flange recess.

14. The motor according to claim 11 , wherein a radial width of the flange recess is greater than a radial width of the rib.

15. the annular gear further includes a hole portion that is disposed on at least one end in the circumferential direction of an inner surface of the flange recess facing one axial direction and that penetrates the flange portion in the axial direction, The motor according to any one of claims 11 to 14, wherein the hole extends radially inward from a radially outer end of the flange portion.

16. A shaft extending along a central axis extending in an axial direction; a rotor rotatable together with the shaft about the central axis; a stator radially opposed to the rotor; a reduction gear connected to the shaft; a hub rotatable about the central axis; Equipped with the reduction gear has an annular gear that surrounds the central shaft and is rotatable about the central shaft; the annular gear has a first contact portion; The hub has a disk hub surrounding the central axis, The disc hub is a disk portion disposed on one side of the annular gear in the axial direction and surrounding the central axis and extending in the radial direction; a second contact portion disposed on the other axial side of the disk portion and capable of coming into contact with the first contact portion in a circumferential direction; and a motor, wherein an axial end of one of the first contact portion and the second contact portion is in axial contact with a member having the other of the first contact portion and the second contact portion, either the annular gear or the disk hub.

17. A shaft extending along a central axis extending in an axial direction; a rotor rotatable together with the shaft about the central axis; a stator radially opposed to the rotor; a reduction gear connected to the shaft; a hub rotatable about the central axis; Equipped with the reduction gear has an annular gear that surrounds the central shaft and is rotatable about the central shaft; the annular gear has a first contact portion; The hub has a disk hub surrounding the central axis, The disc hub is a disk portion disposed on one side of the annular gear in the axial direction and surrounding the central axis and extending in the radial direction; a second contact portion disposed on the other axial side of the disk portion and capable of coming into contact with the first contact portion in a circumferential direction; and The motor, wherein the material of the ring gear is resin.

18. A shaft extending along a central axis extending in an axial direction; a rotor rotatable together with the shaft about the central axis; a stator radially opposed to the rotor; a reduction gear connected to the shaft; a hub rotatable about the central axis; Equipped with the reduction gear has an annular gear that surrounds the central shaft and is rotatable about the central shaft; the annular gear has a first contact portion; The hub has a disk hub surrounding the central axis, The disc hub is a disk portion disposed on one side of the annular gear in the axial direction and surrounding the central axis and extending in the radial direction; a second contact portion disposed on the other axial side of the disk portion and capable of coming into contact with the first contact portion in a circumferential direction; and The motor, wherein an adhesive is filled between the first contact portion and the second contact portion.

19. A motor described in any one of claims 1 to 18, wherein at least one of the first contact portion and the second contact portion is arranged at equal intervals in the circumferential direction.

20. A vehicle comprising a motor according to any one of claims 1 to 19.

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