Drive unit for human-powered vehicle and human-powered vehicle

Abstract

To provide a drive unit for a human-powered vehicle, in which a motor can be suitably mounted to a housing, and to provide a human-powered vehicle.SOLUTION: A drive unit for a human-powered vehicle includes: a housing; a motor arranged inside the housing in order to add propulsive power to the human-powered vehicle; a crank shaft rotatably supported on the housing; a deceleration mechanism for decelerating rotation of the motor by using a toothed gear; and a first shaft on which the toothed gear is supported. The housing includes: a first housing having a first hole through which a first end of the crank shaft projects, and including a concavity for housing the motor; a second housing including a second hole through which a second end of the crank shaft projects; and a support part for supporting the first shaft, which covers a part of the motor housed in a concavity of the second housing and includes a third hole through which a rotation shaft of the motor passes. The concavity of the second housing has a wall part along the periphery of the motor, and the wall part is fixed to the support part.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a drive unit for a human-powered vehicle and a human-powered vehicle. [Background technology]

[0002] Bicycles equipped with drive units are known. For example, Patent Document 1 discloses a drive unit to which a bicycle motor is attached. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2001-218434 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a drive unit for a human-powered vehicle, and a human-powered vehicle, in which a motor can be suitably attached to a housing. [Means for solving the problem]

[0005] A drive unit according to a first aspect of the present disclosure is a drive unit for a human-powered vehicle, comprising a housing and a motor provided in the housing and configured to provide propulsive force to the human-powered vehicle, the motor including a stator, a rotor, and a resin part molded around the stator and formed from a resin material, the resin part being configured to be exposed from the housing, the housing being configured to surround at least a portion of the outer periphery of the stator around the rotational axis of the rotor and configured to contact at least a portion of the outer periphery of the motor around the rotational axis of the rotor. According to the drive unit of the first aspect, the stator of the motor is covered with resin, so that vibration noise of the motor can be suppressed. Furthermore, according to the drive unit of the first aspect, the resin part is exposed from the housing, so that heat can be dissipated directly from the resin part. Furthermore, according to the drive unit of the first aspect, the housing is configured to surround at least a part of the outer periphery of the stator around the rotation axis of the rotor, and contacts at least a part of the outer periphery of the motor around the rotation axis of the rotor, so that the motor can be stably supported.

[0006] In a drive unit according to the first aspect, the resin portion includes a heat dissipation portion, and the heat dissipation portion is configured to be exposed from the housing. According to the drive unit of the second aspect, the heat dissipation portion is exposed from the housing, thereby improving heat dissipation.

[0007] In the drive unit of a third aspect according to the second aspect, the heat dissipation portion includes one or more heat dissipation fins. According to the drive unit of the third aspect, the heat generated by the motor can be efficiently dissipated.

[0008] In a drive unit of a fourth side according to any one of the first to third sides, the motor further includes a plurality of bearings that rotatably support the rotor, and the resin part includes a bearing part that supports one of the plurality of bearings. According to the drive unit of the fourth aspect, since the resin portion includes the bearing portion that supports the bearing, the bearing can be supported in a stable position relative to the stator.

[0009] The drive unit of the fifth aspect according to the fourth aspect further includes a metallic reinforcing member provided on the bearing portion. According to the drive unit of the fifth aspect, the bearing can be stably supported by the metallic reinforcing member provided in the bearing portion that supports the bearing.

[0010] In the drive unit of a sixth aspect according to the fifth aspect, the bearing portion includes a recess, and the reinforcing member is provided in at least the recess. According to the drive unit of the sixth aspect, the reinforcing member is provided at least in the recess, so that the bearing can be stably supported.

[0011] In the drive unit of the seventh side according to the fifth or sixth side, the reinforcing member is integrally molded with the resin portion. According to the drive unit of the seventh aspect, the reinforcing member is integrally molded with the resin portion, and therefore the bearing can be stably supported.

[0012] In a drive unit having an eighth side according to any one of the fifth to seventh sides, the one of the plurality of bearings includes a radial bearing including an inner race, an outer race, and rolling elements, and the outer race is fitted to the reinforcing member. According to the drive unit of the eighth aspect, the outer race body is fitted into the reinforcing member, so that the bearing can be stably supported.

[0013] In a drive unit of a ninth side according to any one of the first to eighth sides, the motor further includes a stopper that restricts movement of the motor in at least one first direction parallel to the rotational axis of the rotor. According to the drive unit of the ninth aspect, the movement of the motor in the first direction parallel to the rotation axis of the rotor is restricted by the stopper, and the motor can be positioned at an appropriate position.

[0014] In the drive unit of the tenth aspect according to the ninth aspect, the stopper includes a metal member. According to the drive unit of the tenth aspect, the strength of the stopper is increased, and the motor can be stably positioned.

[0015] In the drive unit of an eleventh aspect according to the ninth aspect, the resin portion includes the stopper. According to the drive unit of the eleventh aspect, since the resin portion includes the stopper, the number of parts can be reduced.

[0016] In a drive unit of a twelfth side according to a ninth side, the housing includes an accommodating portion that surrounds at least a portion of the outer periphery of the stator around the rotational axis of the rotor and accommodates at least a portion of the motor, and when at least a portion of the motor is accommodated in the accommodating portion, the stopper contacts the housing. According to the drive unit of the twelfth aspect, the motor is stably accommodated in the accommodation portion, so that vibration noise of the motor can be suppressed.

[0017] In a drive unit of a thirteenth side according to any one of the tenth to twelfth sides, the stopper is disposed on an outer periphery of the stator around the rotation axis of the rotor. According to the drive unit of the thirteenth aspect, the motor can be positioned at an appropriate position.

[0018] In a drive unit of a fourteenth aspect according to the thirteenth aspect, the stopper is disposed over the entire outer periphery of the stator around the rotation axis of the rotor. According to the drive unit of the fourteenth aspect, the motor can be stably positioned at an appropriate position.

[0019] In a drive unit of a 15th side according to any one of the 11th to 14th sides, at the outer periphery of the motor around the rotational axis of the rotor, the resin part has a protruding portion that protrudes radially outward from the rotational axis of the rotor, and the stopper is formed by the protruding portion. According to the drive unit of the fifteenth aspect, the motor can be stably positioned at an appropriate position by the protruding portion.

[0020] In a drive unit having a 16th side which corresponds to any one of the 9th to 15th sides, the resin part includes a first resin part which molds the stator and is formed substantially cylindrical, and a second resin part which is connected to one end of the first resin part in the first direction and is formed substantially disc-shaped. According to the drive unit of the sixteenth aspect, the end of the first resin part is connected to the second resin part, so that the rigidity is increased and vibration noise of the motor can be suppressed.

[0021] In the drive unit on a 17th side surface conforming to the 16th surface, the stopper includes a step formed at a connection portion between the first resin portion and the second resin portion. According to the drive unit of the seventeenth aspect, the number of parts can be reduced.

[0022] In the drive unit of an eighteenth aspect according to any one of the first to seventeenth aspects, the motor is fixed to the housing by an adhesive. According to the drive unit of the eighteenth aspect, since the motor is fixed to the housing with an adhesive, the connection area between the motor and the housing can be increased.

[0023] In a drive unit of a 19th side according to any one of the 1st to 18th sides, the stator includes a stator core and a coil, the rotor includes a rotor core and a magnet, and the resin part molds at least a portion of the stator core and at least a portion of the coil. According to the drive unit of the nineteenth aspect, at least a portion of the stator core and the coil are covered with resin, so that vibration noise of the motor can be suppressed.

[0024] In a drive unit of a twentieth aspect according to any one of the first to nineteenth aspects, the housing is configured to rotatably support a crankshaft of the human-powered vehicle. According to the drive unit of the twentieth aspect, the crankshaft can be disposed adjacent to the motor. Effect of the Invention

[0025] In the drive unit for a human-powered vehicle and the human-powered vehicle of the present disclosure, the motor can be suitably attached to the housing. [Brief description of the drawings]

[0026] [Figure 1] 1 is a side view of a human-powered vehicle including a drive unit according to a first embodiment. [Diagram 2] FIG. 2 is a perspective view of the drive unit of FIG. 1; [Diagram 3] FIG. 4 is a side view of the first housing including a cross section of the motor. [Figure 4] 2 is a perspective view of a first housing of the drive unit of FIG. 1; [Diagram 5] FIG. 2 is a cross-sectional view of the drive unit of FIG. 1 . [Figure 6] FIG. 2 is a cross-sectional view of a stator and a resin part of the drive unit in FIG. 1. [Figure 7] FIG. 11 is a cross-sectional view of a stator and a resin portion of a drive unit according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] (First embodiment) With reference to FIG. 1, a drive unit 20 of a human-powered vehicle 10 of a first embodiment will be described. The drive unit 20 is used in the human-powered vehicle 10. The human-powered vehicle 10 is a vehicle that can be driven at least by human driving force. The human-powered vehicle 10 is not limited in the number of wheels, and includes, for example, one-wheeled vehicles and vehicles with three or more wheels. The human-powered vehicle 10 includes, for example, various types of bicycles such as mountain bikes, road bikes, city bikes, cargo bikes, and recumbent bikes, kick scooters, and electric bicycles (E-bikes). Electric bicycles include electrically assisted bicycles that assist the propulsion of the vehicle with an electric motor. In the following embodiments, the human-powered vehicle 10 will be described as a bicycle.

[0028] The human-powered vehicle 10 includes a motor 50 that provides a propulsive force to the human-powered vehicle 10, a crankshaft 92, and a driving wheel 26A. The human-powered vehicle 10 preferably includes a transmission T configured to change a gear ratio R of the rotational speed of the driving wheel 26A relative to the rotational speed of the crankshaft 92. The transmission T includes at least one of an external transmission and an internal transmission. The external transmission includes a derailleur. The derailleur includes at least one of a front derailleur and a rear derailleur. The internal transmission may be provided in the driving wheel 26A or may be provided in the drive unit 20. In this embodiment, the transmission T includes a rear derailleur. The human-powered vehicle 10 further includes a driven wheel 26B, a crank 90, and a frame F. Human driving force is input to the crank 90. The crank 90 includes a crankshaft 92 rotatable with respect to the frame F, and crank arms 94 provided at the ends of the crankshaft 92 in the axial direction A1. A pair of pedals PD are respectively connected to each crank arm 94. The drive wheel 26A is driven by the rotation of the crank 90. ​​The drive wheel 26A is supported by the frame F. The crank 90 and the drive wheel 26A are connected by a drive mechanism 28. The drive mechanism 28 includes a first rotating body 22A connected to the crankshaft 92. The crankshaft 92 and the first rotating body 22A may be connected via a first one-way clutch 42. The first one-way clutch 42 is configured to rotate the first rotating body 22A forward when the crank 90 rotates forward, and to allow relative rotation between the crankshaft 92 and the first rotating body 22A when the crank 90 rotates backward. The first rotating body 22A includes a sprocket, a pulley, or a bevel gear. The drive mechanism 28 further includes a second rotating body 22B and a connecting member 29. The connecting member 29 transmits the rotational force of the first rotating body 22A to the second rotating body 22B. The connecting member 29 includes, for example, a chain, a belt, or a shaft.

[0029] The second rotating body 22B is connected to the driving wheel 26A. The second rotating body 22B includes a sprocket, a pulley, or a bevel gear. A second one-way clutch is preferably provided between the second rotating body 22B and the driving wheel 26A. The second one-way clutch is configured to rotate the driving wheel 26A forward when the second rotating body 22B rotates forward, and to allow relative rotation with the driving wheel 26A when the second rotating body 22B rotates backward. In this embodiment, the first rotating body 22A includes one sprocket, and the second rotating body 22B includes multiple sprockets.

[0030] One of the driving wheel 26A and the driven wheel 26B includes a front wheel. The other of the driving wheel 26A and the driven wheel 26B includes a rear wheel. The front wheel is attached to the frame F via a front fork FF. A handlebar H1 is connected to the front fork FF via a stem H2. In the first embodiment, the rear wheel is described as the driving wheel 26A, but the front wheel may be the driving wheel 26A.

[0031] The motor 50 is configured to provide a propulsive force for the human-powered vehicle 10. The motor 50 includes an electric motor. The motor 50 is configured to transmit rotation to a power transmission path of the human-powered driving force from the pedal PD to the rear wheels, or to the front wheels. The power transmission path of the human-powered driving force from the pedal PD to the rear wheels includes the rear wheels. In this embodiment, the motor 50 is configured to transmit rotation to the first rotor 22A. The motor 50 constitutes a part of the drive unit 20. The drive unit 20 is provided on the frame F. A third one-way clutch 44 is preferably provided between the motor 50 and the power transmission path of the human-powered driving force so that the motor 50 is not rotated by the rotational force of the crank 90 when the crankshaft 92 is rotated in the forward direction of the human-powered vehicle 10. In this embodiment, the motor 50 is configured to transmit torque upstream of the transmission T in the transmission path of the human-powered driving force input to the crankshaft 92.

[0032] As shown in FIG. 2, the drive unit 20 includes a housing 30 and a motor 50 that is provided in the housing 30 and configured to provide a propulsive force to the human-powered vehicle 10. The housing 30 accommodates a part of a crankshaft 92. The housing 30 is configured to rotatably support the crankshaft 92 of the human-powered vehicle 10. The crankshaft 92 is disposed penetrating the housing 30 such that both ends of the crankshaft 92 in the axial direction A1 protrude from the housing 30. In this embodiment, the motor 50 is provided in the housing 30 such that the rotation axis of the motor 50 is parallel to the crankshaft 92. The motor 50 may be an axial gap type motor or a radial gap type motor. An example of the motor 50 is a synchronous motor. As the motor 50, various motors such as an inner rotor type brushless motor, an outer rotor type brushless motor, a DC motor, and an induction motor can be used.

[0033] The housing 30 includes a first housing 30A and a second housing 30B. The second housing 30B is attached to the first housing 30A. The housing 30 may be made of a metal material, a resin material, or both a metal material and a resin material. For example, an aluminum alloy or a magnesium alloy is used as the metal material constituting the housing 30. For example, a polyphenylene sulfide (PPS) or a polybutylene terephthalate (PBT) is used as the resin material constituting the housing 30.

[0034] FIG. 3 shows the state in which the second housing 30B of the housing 30 in the first embodiment is removed. FIG. 3 shows the first housing 30A and the motor 50 cut along a plane perpendicular to the rotation shaft 86 of the motor 50. The motor 50 includes a stator 60, a rotor 70, and a resin part 52 that molds the stator 60 and is formed of a resin material. For example, PPS or PBT is used as the resin material that constitutes the resin part 52. The stator 60 includes a stator core 62 and a coil 64, the rotor 70 includes a rotor core 72 and a magnet 74, and the resin part 52 molds at least a part of the stator core 62 and at least a part of the coil 64. The motor 50 includes a plurality of terminal members 64A that are connected to the coil 64 (see FIG. 6). The rotor core 72 and the stator core 62 are formed of a metal material. A known material is used as the metal material that forms the rotor core 72 and the stator core 62. The stator core 62 includes a back yoke portion 62A formed in a substantially cylindrical shape and a plurality of teeth portions 62B extending radially from the inner peripheral surface of the back yoke portion 62A. The back yoke portion 62A may be integrally formed in the circumferential direction of the rotating shaft 86 of the motor 50, or may be formed in a divided manner. The teeth portion 62B is formed integrally with the back yoke portion 62A. The stator core 62 may be configured by laminating a plurality of electromagnetic steel plates in a direction A3 parallel to the rotation axis of the rotating shaft 86 of the motor 50. The coil 64 is wound around the teeth portion 62B. In FIG. 3, only a part of the coil 64 is shown to prevent the drawing from becoming complicated. The rotor core 72 has a hole 72B penetrating in a direction A3 parallel to the rotation axis of the rotating shaft 86 of the motor 50. The rotor core 72 includes a substantially cylindrical base portion 72A. The rotor 70 is provided on the outer periphery of the rotating shaft 86 of the motor 50. The rotor 70 is configured to rotate integrally with the rotating shaft 86. A part of the rotating shaft 86 is disposed in the hole 72B of the base portion 72A, and the rotating shaft 86 passes through the base portion 72A. The outer periphery of the rotating shaft 86 is fixed to the inner periphery that defines the hole 72B of the base portion 72A. The base portion 72A may be fixed to the rotating shaft 86 by a bolt, by caulking, or by an adhesive.The base portion 72A may be formed integrally with the rotating shaft 86. The base portion 72A may be configured by laminating a plurality of electromagnetic steel plates in a direction A3 parallel to the rotation axis of the rotating shaft 86 of the motor 50. The base portion 72A is configured to hold a plurality of permanent magnets 74A. The plurality of permanent magnets 74A are arranged at intervals in the circumferential direction of the rotating shaft 86 of the motor 50. The structures of the rotor 70 and the stator 60 are not particularly limited, and various structures can be adopted.

[0035] In this embodiment, the stator 60 is disposed along an outer circumferential surface of the rotor 70 centered on the rotation axis C2. The housing 30 is configured to surround at least a part of the outer circumferential portion of the stator 60 around the rotation axis C2 of the rotor 70. The housing 30 includes an accommodating portion 38. The accommodating portion 38 is configured to surround at least a part of the outer circumferential portion of the stator 60 around the rotation axis C2 of the rotor 70 and to accommodate at least a part of the motor 50. The housing 30 is configured to contact at least a part of the outer circumferential portion of the motor 50 around the rotation axis C2 of the rotor 70. Preferably, the accommodating portion 38 is configured to surround the entire circumference of the stator 60 around the rotation axis C2 of the rotor 70. The accommodating portion 38 may be configured to surround the entire circumference of the stator 60 continuously or intermittently around the rotation axis C2 of the rotor 70. As shown in FIG. 4, the accommodation portion 38 has an opening 38A on the outer circumferential surface of the housing 30 in a direction parallel to the axial direction A1 of the crankshaft 92. The accommodation portion 38 forms a substantially cylindrical accommodation space SA. The accommodation portion 38 includes a wall portion 36 that defines the accommodation space SA. The wall portion 36 may be formed so that the inner diameter becomes smaller from the opening 38A toward the second housing 30B. The wall portion 36 is configured to come into contact with at least a part of the outer circumferential portion of the motor 50 and to hold the motor 50. The inner circumferential surface of the wall portion 36 is preferably formed in a cylindrical shape. The wall portion 36 is preferably configured to overlap the stator core 62 when viewed from a direction perpendicular to the rotation shaft 86 of the motor 50. The wall portion 36 is more preferably configured to overlap more than half of the stator core 62 in a direction A3 parallel to the rotation axis of the rotation shaft 86 of the motor 50 when viewed from a direction perpendicular to the rotation shaft 86 of the motor 50. More preferably, the wall portion 36 is configured to overlap the entire stator core 62 in a direction A3 parallel to the rotation axis of the rotation shaft 86 of the motor 50 when viewed from a direction perpendicular to the rotation shaft 86 of the motor 50 .

[0036] As shown in FIG. 5, the first housing 30A and the second housing 30B are attached to each other by bolts in a state in which the first mounting surface 30S of the first housing 30A and the second mounting surface 32S of the second housing 30B are overlapped. In addition to a part of the motor 50 and a part of the crankshaft 92, a part of the output unit 48, the reduction mechanism 84, and the clutch mechanism 96 are accommodated in a space S formed by the first housing 30A and the second housing 30B. The part of the motor 50 arranged in the space S includes a part of the rotating shaft 86 of the motor 50. The part of the crankshaft 92 arranged in the space S includes an intermediate portion of the crankshaft 92 in the axial direction A1 except for the first end 92A and the second end 92B. The part of the output unit 48 arranged in the space S includes a portion of the output unit 48 in the axial direction A1 of the crankshaft 92 except for the first end 48A.

[0037] The resin part 52 is configured to be exposed from the housing 30. The resin part 52 includes a heat dissipation part 54. The heat dissipation part 54 is configured to be exposed from the housing 30. In one example, the heat dissipation part 54 includes one or more heat dissipation fins 54A. In this embodiment, the heat dissipation part 54 has a plurality of heat dissipation fins 54A. In a state in which the drive unit 20 is attached to the frame F, the plurality of heat dissipation fins 54A are preferably configured to extend along the traveling direction B1 of the human-powered vehicle 10 (see FIG. 1). The plurality of heat dissipation fins 54A are arranged side by side at equal intervals in a predetermined direction. The heat dissipation part 54 is provided at a first end 52D of the resin part 52 in a direction A3 parallel to the rotation axis of the rotation shaft 86 of the motor 50. The resin part 52 is arranged outside both ends 62C, 62D of the stator core 62 in a direction A3 parallel to the rotation axis of the rotation shaft 86 of the motor 50. The resin part 52 is preferably configured to completely cover the coil 64. A plurality of terminal members 64A connected to the coil 64 are exposed from the resin part 52. The stator 60 may include a coil bobbin. When the stator 60 includes a coil bobbin, the resin part 52 molds the coil bobbin. The resin part 52 molds the stator 60 and includes a first resin part 52A formed substantially in a cylindrical shape, and a second resin part 52B connected to one end 52C of the first resin part 52A in the first direction A4 and formed substantially in a disk shape. The resin part 52 molds the stator 60 around the rotation shaft 86 of the motor 50, preferably such that at least a part of the outer periphery of the stator core 62 is exposed. The resin part 52 may mold the stator 60 around the rotation shaft 86 of the motor 50 such that the outer periphery of the stator core 62 is not exposed. The resin portion 52 may mold the stator 60 such that the outer periphery of the stator core 62 is exposed around the rotating shaft 86 of the motor 50. In this embodiment, a groove 65 extending along the rotating shaft 86 of the motor 50 is formed in the outer periphery of the stator core 62 around the rotating shaft 86 of the motor 50. The groove 65 extends to both end faces of the stator core 62 in the extension direction of the rotating shaft 86 of the motor 50. The groove 65 is disposed at a position corresponding to the teeth portion 62B in the circumferential direction of the rotating shaft 86 of the motor 50.The width of the groove 65 in the circumferential direction of the rotating shaft 86 of the motor 50 is smaller than the width of the teeth portion 62B in the circumferential direction of the rotating shaft 86 of the motor 50. A part of the resin portion 52 is disposed in the groove 65. The groove 65 may be omitted. The resin portion 52 may be formed to surround the stator core 62 around the rotating shaft 86 of the motor 50 so that the outer peripheral surface of the stator core 62 is not exposed, and the stator 60 may be molded. In the first embodiment, the wall portion 36 is configured to surround at least a part of the outer periphery of the first resin portion 52A around the rotating shaft 86 of the motor 50 and to contact at least a part of the second resin portion 52B. The motor 50 is fixed to the housing 30, for example, by an adhesive. The motor 50 may be fixed to the housing 30 by a bolt. When the motor 50 is fixed to the housing 30 by an adhesive, the adhesive is provided on the parts of the first resin portion 52A and the second resin portion 52B that face the housing 30. Preferably, the adhesive is provided between the outer periphery of the first resin portion 52A around the rotation shaft 86 of the motor 50 and the wall portion 36 of the housing 30.

[0038] The motor 50 further includes a plurality of bearings 80 that rotatably support the rotor 70. The resin part 52 includes a bearing part 58 that supports one of the plurality of bearings 80. The bearing part 58 is provided in the second resin part 52B. In this embodiment, the plurality of bearings 80 include a first bearing 81A and a second bearing 81B. The bearing part 58 supports the first bearing 81A. The first bearing 81A and the second bearing 81B are provided on both sides of the rotor 70 in the direction in which the rotating shaft 86 extends. The drive unit 20 further includes a metallic reinforcing member 58A provided in the bearing part 58. For example, an aluminum alloy or an iron alloy is used as the metallic material for forming the reinforcing member 58A. The bearing part 58 includes a recess 58B. The recess 58B includes a first wall surface 58C that surrounds the rotating shaft 86 and a second wall surface 58D that faces the rotating shaft 86. The first wall surface 58C is formed in a cylindrical shape. The second wall surface 58D is formed, for example, in a plane. The second wall surface 58D is preferably formed so as to be perpendicular to the extending direction of the rotation shaft 86. The reinforcing member 58A is provided at least in the recessed portion 58B. The reinforcing member 58A is preferably provided on the first wall surface 58C of the recessed portion 58B. The reinforcing member 58A is more preferably provided on the first wall surface 58C and the second wall surface 58D of the recessed portion 58B in the resin portion 52. The reinforcing member 58A is more preferably provided on the portion of the second resin portion 52B surrounding the opening 58E of the recessed portion 58B. The reinforcing member 58A is formed, for example, by pressing a plate-shaped member. Preferably, the reinforcing member 58A is integrally molded with the resin portion 52. The reinforcing member 58A may be fixed to the resin portion 52 by an adhesive or may be fixed by a bolt. One of the multiple bearings 80 includes a radial bearing including an inner race body 80R, an outer race body 80S, and rolling elements 80T. All of the multiple bearings 80 may be radial bearings. The outer race body 80S is fitted into the reinforcing member 58A. The outer race body 81S of the first bearing 81A may be fixed to the reinforcing member 58A by, for example, press fitting. The inner peripheral surface of the inner race body 81R of the first bearing 81A is attached to the outer peripheral surface of the rotating shaft 86 of the motor 50. The inner race body 80R of the bearing 80 is fixed to the rotating shaft 86 of the motor 50 by, for example, press fitting.The inner race 80R of the bearing 80 may be integrally formed with the rotating shaft 86 of the motor 50. The inner race 80R of the first bearing 81A may be attached to the rotating shaft 86 of the motor 50 so as to be relatively rotatable. The rolling element 81T of the first bearing 81A is disposed between the outer race 81S and the inner race 81R. The rolling element 81T may be, for example, a ball, a cylinder, or a column. In the direction A3 parallel to the rotation axis of the rotating shaft 86 of the motor 50, the reinforcing member 58A preferably extends over the entire bearing 80. In the direction A3 parallel to the rotation axis of the rotating shaft 86 of the motor 50, preferably, more than half of the bearing 80 is provided in the space formed by the recess 58B.

[0039] As shown in FIG. 5, the first housing 30A includes a first hole 92C through which the first end 92A of the crankshaft 92 and the first end 48A of the output unit 48 protrude. The support unit 30C is attached to the first housing 30A. The support unit 30C is disposed in the space S. The support unit 30C includes a third hole 30D through which the rotating shaft 86 of the motor 50 passes. The support unit 30C has a substantially disk shape. The support unit 30C has an annular flange on the outer periphery around the rotating shaft 86 of the motor 50 that protrudes in the other direction D2 of the first direction A4 parallel to the rotating axis C2 of the rotor 70. The support unit 30C is fixed to the first housing 30A by, for example, a bolt in a state in which the flange is in contact with the first housing 30A. The support unit 30C may be integrally molded with the first housing 30A. The second housing 30B includes a second hole 92D through which the second end 92B of the crankshaft 92 protrudes. The output section 48 is a hollow shaft and is disposed around the crankshaft 92 so that the rotation axis C1 of the crankshaft 92 and the rotation axis of the output section 48 are aligned. The output section 48 is rotatably supported relative to the housing 30 by a third bearing 82A disposed in the vicinity of the first hole 92C of the first housing 30A and inside the housing 30. Preferably, a transmission shaft 49 is provided in the transmission path of the manual driving force between the crankshaft 92 and the output section 48. The transmission shaft 49 is formed in a substantially cylindrical shape. The transmission shaft 49 is disposed coaxially with the crankshaft 92. In a direction parallel to the axial direction A1 of the crankshaft 92, one end 49A of the transmission shaft 49 has a spline on its inner periphery. The spline of the transmission shaft 49 fits into a spline formed on the outer periphery of the crankshaft 92. When the drive unit 20 is provided with the first one-way clutch 42, an outer race of the first one-way clutch 42 is provided on an inner periphery of the second end 48B of the output portion 48. The second end 48B of the output portion 48 and the outer race of the first one-way clutch 42 may be formed integrally. When the drive unit 20 is provided with the first one-way clutch 42, an inner race of the first one-way clutch 42 is provided on an outer periphery of the other end 49B of the transmission shaft 49 in a direction parallel to the axial direction A1 of the crankshaft 92. The other end 49B of the transmission shaft 49 and the inner race of the first one-way clutch 42 may be formed integrally.A fourth bearing 82B is provided between the outer periphery of the crankshaft 92 and the inner periphery of the output portion 48. The fourth bearing 82B includes, for example, a needle bearing. The crankshaft 92 is supported by the output portion 48 via the fourth bearing 82B. A second end portion 92B of the crankshaft 92 is rotatably supported with respect to the housing 30 by a fifth bearing 82C provided in the vicinity of the second hole 92D of the second housing 30B and inside the housing 30. When the drive unit 20 is not provided with the first one-way clutch 42, the transmission shaft 49 and the output portion 48 may be integrally formed, the crankshaft 92 and the transmission shaft 49 may be integrally formed, or the crankshaft 92, the transmission shaft 49, and the output portion 48 may be integrally formed.

[0040] An intermediate portion of the rotating shaft 86 of the motor 50 in a direction parallel to the rotation axis C2 of the rotor 70 is rotatably supported relative to the housing 30 by a second bearing 81B provided in a third hole 30D of the support portion 30C. A first end portion 86A of the rotating shaft 86 is rotatably supported relative to the housing 30 by a first bearing 81A that fits into the bearing portion 58 of the housing 30.

[0041] In this embodiment, the clutch mechanism 96 includes a first one-way clutch 42 and a third one-way clutch 44. The first one-way clutch 42 is provided between the crankshaft 92 and the output portion 48. The third one-way clutch 44 is provided in the reduction mechanism 84. In the case where the first one-way clutch 42 is omitted, a spline is formed on the inner periphery of the second end portion 48B of the output portion 48, and is configured to fit into a spline formed on the outer periphery of the crankshaft 92.

[0042] The reduction mechanism 84 includes a first gear 68A provided on a second end 86B of a rotating shaft 86 of the motor 50, a second gear 68B meshing with the first gear 68A, a third gear 68C rotating integrally with the second gear 68B, a fourth gear 68D meshing with the third gear 68C, and a fifth gear 68E connected to the fourth gear 68D via a third one-way clutch 44. The fifth gear 68E meshes with a sixth gear 68F provided on the output section 48. The second gear 68B and the third gear 68C are supported by the first shaft 83A. The second gear 68B and the third gear 68C are fixed to the first shaft 83A so as to rotate integrally with the first shaft 83A. At least one of the second gear 68B and the third gear 68C may be integrally formed with the first shaft 83A. The first shaft 83A is rotatably supported by a sixth bearing 82F provided in the second housing 30B and a seventh bearing 82G provided in the support portion 30C. The first shaft 83A is arranged parallel to the rotating shaft 86 of the motor 50. The fourth gear 68D and the fifth gear 68E are supported by the second shaft 83B. The second shaft 83B is provided with a third one-way clutch 44. The second shaft 83B is rotatably supported by an eighth bearing 82H provided in the second housing 30B and a ninth bearing 82J provided in the first housing 30A. The second shaft 83B is arranged parallel to the rotating shaft 86 of the motor 50. The third one-way clutch 44 is provided on the second shaft 83B, but may be provided on the first shaft 83A. The third one-way clutch 44 includes, for example, a roller clutch. The configuration of the reduction mechanism 84 is not limited thereto. For example, the speed reduction mechanism 84 may be configured to reduce the speed in one stage using two gears, reduce the speed in two stages using four gears, or reduce the speed in four or more stages using eight or more gears. The speed reduction mechanism 84 may include any one of a planetary gear mechanism, a belt, and a chain.

[0043] FIG. 6 shows an enlarged view of the stator 60 and the resin part 52. As shown in FIG. 6, the motor 50 further includes a stopper 56. The stopper 56 restricts the movement of the motor 50 in at least one direction D1 of the first direction A4 parallel to the rotation axis C2 of the rotor 70. In the first embodiment, the resin part 52 includes the stopper 56. In a state in which at least a part of the motor 50 is accommodated in the accommodation part 38, the stopper 56 contacts the housing 30. The stopper 56 is disposed on the outer periphery of the stator 60 around the rotation axis C2 of the rotor 70. In one example, the stopper 56 is disposed over the entire circumference of the outer periphery of the stator 60 around the rotation axis C2 of the rotor 70. The stopper 56 may be formed only on a part of the outer periphery of the stator 60 around the rotation axis C2 of the rotor 70, or may be disposed at intervals in the circumferential direction. At the outer periphery of the motor 50 around the rotation axis C2 of the rotor 70, the resin part 52 has a protruding part 57 that protrudes radially outward from the rotation axis C2 of the rotor 70. The stopper 56 is formed by the protruding part 57. In one example, the stopper 56 includes a step 56A formed at a connection part between the first resin part 52A and the second resin part 52B. In the first embodiment, in a direction A3 parallel to the rotation axis of the rotation shaft 86 of the motor 50, the stopper 56 is configured to come into contact with the housing 30 when the entire stator core 62 is accommodated in the accommodation part 38.

[0044] Second embodiment The drive unit 20 of the second embodiment is different from the drive unit 20 of the first embodiment in the material of the stopper 56 constituting the motor 50. The same reference numerals as those in the first embodiment are used for the configurations common to the first embodiment, and the overlapping description will be omitted. In the second embodiment, as shown in FIG. 7, the stopper 56 includes a metal member 98. The metal member 98 constituting the stopper 56 may be insert-molded into the first resin part 52A and embedded in the first resin part 52A. The metal member 98 may be plate-shaped. The metal member 98 is formed of, for example, an aluminum alloy or an iron alloy. The shape of the metal member 98 is not particularly limited as long as it is designed to match the shape of the motor 50 in order to define the position where the motor 50 is accommodated. The stopper 56 may be formed at the connection part between the first resin part 52A and the second resin part 52B.

[0045] <Modification> The description of each embodiment is merely an example of a form that the drive unit 20 according to the present disclosure can take, and is not intended to limit the form. In the following modified examples, parts that are common to the embodiments are given the same reference numerals as in the embodiments, and descriptions thereof are omitted.

[0046] In each embodiment, the drive unit 20 can also be applied to a drive unit 20 that is not configured to rotatably support the crankshaft 92 of the human-powered vehicle 10. The drive unit 20 that is not configured to rotatably support the crankshaft 92 of the human-powered vehicle 10 includes, for example, a hub motor.

[0047] In each embodiment and its modified examples, the stopper 56 may restrict movement of the motor 50 in the other direction D2 of the first direction A4 parallel to the rotational axis C2 of the rotor 70, or may restrict movement of the motor 50 in one direction D1 and the other direction D2 of the first direction A4 parallel to the rotational axis C2 of the rotor 70.

[0048] In each embodiment and its modified examples, grooves extending along the rotation shaft 86 of the motor 50 and facing each other may be formed in the outer periphery of the stator core 62 or the resin part 52 around the rotation shaft 86 of the motor 50 and in the housing 30, and a key member that regulates the relative rotation between the stator 60 and the housing 30 around the rotation shaft 86 of the motor 50 may be fitted into this groove.

[0049] As used herein, sentences containing the phrase "at least one" may be understood as follows: If the sentence contains two options, the sentence means that the sentence contains only one of the options or two of the options. If the sentence contains more than two options, the sentence means that the sentence contains only one of the options or any combination of two or more of the options. [Explanation of symbols]

[0050] 10...human-powered vehicle, 20...drive unit, 30...housing, 38...accommodation section, 50...motor, 52...resin section, 52A...first resin section, 52B...second resin section, 54...heat dissipation section, 54A...heat dissipation fin, 56...stopper, 56A...step, 58...bearing section, 58A...reinforcing member, 58B...recess, 60...stator, 62...stator core, 64...coil, 70...rotor, 72...rotor core, 74...magnet, 80...bearing, 80R...inner race, 80S...outer race, 80T...rolling element, 92...crankshaft, C2...rotation axis.

Claims

1. A drive unit for a human-powered vehicle provided on a frame for the human-powered vehicle, Housing and a motor disposed within the housing and configured to provide propulsion to the human powered vehicle, the motor including a stator; a crankshaft rotatably supported by the housing; a transmission shaft that is arranged coaxially with the crankshaft and has one end that fits into a spline formed on an outer periphery of the crankshaft; a first one-way clutch provided between a first rotor including a sprocket and the transmission shaft; a reduction gear mechanism having a predetermined gear to which a rotational force of the rotation shaft of the motor is transmitted; a first shaft having the predetermined gear provided on an outer periphery thereof and being a shaft different from the rotation shaft of the motor; a resin portion formed by molding the stator and using a resin material; The housing includes: a first housing including a first hole through which a first end of the crankshaft projects and a recess that accommodates the stator; a second housing including a second hole through which the second end of the crankshaft projects; a support portion that covers a portion of the motor accommodated in the recess of the first housing, includes a third hole through which the rotating shaft of the motor passes, and supports the first shaft, the recess of the first housing has a wall portion that follows a periphery of the motor, the support portion has an annular flange on an outer periphery around the rotation shaft of the motor, the support portion is fixed to the first housing by a bolt in a state in which a first surface of the flange on the stator side is in contact with the first housing, the first housing has a first protrusion and a first recess in a first portion of the flange of the support portion corresponding to the first surface on the stator side, the resin portion is in contact with the wall portion and the support portion, a portion of the first portion that is in contact with the first surface extends in a circumferential direction with respect to a rotation axis of the motor and is a flat surface that faces the first surface, The first convex portion and the first concave portion are provided on the plane.

2. The drive unit according to claim 1 , wherein the support portion rotatably supports the rotating shaft of the motor.

3. The drive unit according to claim 2 , wherein the first portion of the support portion corresponding to the flange has a plurality of the first recesses provided at intervals in the circumferential direction.

4. The drive unit according to claim 2 , wherein the first portion of the support portion corresponding to the flange has a plurality of first protrusions provided at intervals in the circumferential direction.

5. The drive unit according to claim 1 , wherein the support portion is not exposed to an outside of an accommodation space enclosed by the first housing and the second housing.

6. A human-powered vehicle, A human-powered vehicle comprising a drive unit for a human-powered vehicle according to any one of claims 1 to 5.

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