JP2022041319A - Drive unit for man-powered vehicle - Google Patents

Abstract

To provide a drive unit for a man-powered vehicle capable of being downsized in a direction in which a reduction shaft extends.SOLUTION: A drive unit includes a base, motor, and a speed reducer. The motor includes an output shaft extending in a predefined direction, a rotor, and a stator. The speed reducer includes on its periphery a first tooth formed at a first end of the output shaft, at least one bearing which bears a reduction shaft, and a second tooth which is engaged with the first tooth, a second gear mounted on the reduction shaft, and a third tooth, and further includes a third gear which is mounted on the reduction shaft and to which the torque of the second gear is transmitted. The at least one bearing includes a first bearing and a second bearing disposed at a position in the predefined direction which is closer to the rotor and stator than to the first bearing. In the predefined direction, the third tooth is located at a position which is closer to the rotor and stator than to the second tooth. The second gear has a diameter larger than the diameter of the third gear. At least a part of the first bearing is disposed inside the second tooth in a radial direction of the second gear.SELECTED DRAWING: Figure 7

Description

The present invention relates to a drive unit for a human-powered vehicle.

For example, the component for a human-powered vehicle disclosed in Patent Document 1 includes a speed reducer. The reducer includes a reduction shaft supported by a bearing.

Japanese Unexamined Patent Publication No. 2018-158695

One of the objects of the present disclosure is to provide a drive unit for a human-powered vehicle that can be miniaturized in the direction in which the reduction shaft extends.

The drive unit according to the first aspect of the present disclosure is a drive unit for a human-powered vehicle, and includes a base portion, a motor provided on the base portion and configured to apply propulsive force to the human-powered vehicle, and the above-mentioned. A speed reducer provided on the base portion and configured to transmit the driving force of the motor to the rotating body is provided, the motor extends in a predetermined direction, and is free at the first end portion in the predetermined direction. The speed reducer has a first tooth portion provided at the first end portion of the output shaft, which has an output shaft having an end, a rotor fixed to the output shaft, and a stator facing the rotor. A reduction shaft extending substantially parallel to the predetermined direction, at least one bearing supporting the reduction shaft, and a second tooth portion that meshes with the first tooth portion are provided on the outer peripheral portion of the reduction shaft. The speed reducer has a second gear provided in the reduction gear and a third gear provided on the reduction shaft and having a third tooth portion on the outer peripheral portion and to which the rotational force of the second gear is transmitted. The at least one bearing has a first bearing and a second bearing arranged at a position closer to the rotor and the stator than the first bearing in the predetermined direction, and in the predetermined direction. The third tooth portion is arranged closer to the rotor and the stator than the second tooth portion, the second gear has a diameter larger than the diameter of the third gear, and the first bearing has a diameter larger than that of the third gear. At least a part of the above is arranged inside the second tooth portion in the radial direction of the second gear.
According to the drive unit on the first side surface, at least a part of the first bearing is arranged inside the second tooth portion in the radial direction of the second gear, so that the size can be reduced in the extending direction of the reduction shaft. According to the drive unit on the first side surface, it is easy to arrange the first tooth portion close to the end surface of the first end portion of the output shaft in a predetermined direction.

The drive unit on the second side according to the first side of the present disclosure has a connection part to which the rotating body is connected, and further includes an output part connected to the speed reducer.
According to the drive unit on the second side surface, the driving force of the motor can be suitably transmitted to the rotating body by the output unit.

In the drive unit on the third side according to the second side of the present disclosure, the output unit is configured to rotate around a rotation axis extending in the predetermined direction, and the connection portion of the output unit is configured in the predetermined direction. , It is arranged at a position closer to the second gear than the third gear.
According to the drive unit on the third side surface, it is easy to configure the distance of the power transmission path from the first gear to the connection portion of the output unit to be short.

The drive unit according to the fourth aspect of the present disclosure is a drive unit for a human-powered vehicle, and includes a base portion, a motor provided on the base portion and configured to apply propulsive force to the human-powered vehicle, and the above-mentioned. A speed reducer provided on a base portion and configured to transmit the driving force of the motor, and an output unit having a connection portion to which a rotating body is connected and connected to the speed reducer are provided. The motor has an output shaft extending in a predetermined direction, a rotor fixed to the output shaft, and a stator facing the rotor, and the speed reducer has a first tooth portion provided on the output shaft. A second outer peripheral portion having a deceleration shaft extending in parallel in the predetermined direction, at least one bearing for supporting the deceleration shaft, and a second tooth portion provided on the deceleration shaft and meshing with the first tooth portion. It has a gear and a third gear provided on the reduction shaft, having a third tooth portion on the outer peripheral portion, and a third gear to which the rotational force of the second gear is transmitted, and the at least one bearing of the reduction gear. Has a first bearing and a second bearing arranged at a position closer to the rotor and the stator than the first bearing in the predetermined direction, and the second tooth portion in the predetermined direction. Is located closer to the rotor and the stator than the third tooth portion, the second gear has a diameter larger than the diameter of the third gear, and at least a part of the first bearing is , The output portion is arranged inside the second tooth portion in the radial direction of the second gear, and the output portion is configured to rotate around a rotation axis extending in the predetermined direction, and the connection portion of the output portion. Is arranged at a position closer to the second gear than the third gear in the predetermined direction.
According to the drive unit on the fourth side surface, at least a part of the first bearing is arranged inside the second tooth portion in the radial direction of the second gear, so that the size can be reduced in the extending direction of the reduction shaft. According to the drive unit on the fourth side surface, it is easy to configure the distance of the power transmission path from the first gear to the connection portion of the output unit to be short.

In the drive unit on the fifth side according to the third or fourth side surface of the present disclosure, a third bearing provided on the base portion and rotatably supporting the output portion is further provided.
According to the drive unit on the fifth side surface, the output unit can be smoothly rotated.

In the drive unit of the sixth side surface according to the fifth side surface of the present disclosure, the second gear includes the first end face and the second end face in the predetermined direction, includes the first end face, and is said in advance. At least a part of the third bearing is arranged between the first plane perpendicular to the predetermined direction and the second plane including the second end surface and perpendicular to the predetermined direction.
According to the drive unit on the sixth side surface, the portion where the third bearing is arranged can be miniaturized in a predetermined direction.

In the drive unit on the seventh side according to the sixth side of the present disclosure, the second gear includes a first end face and a second end face in the predetermined direction, and the third bearing is the first plane. , The whole is arranged between the second plane and the second plane.
According to the drive unit on the seventh side surface, the portion where the third bearing is arranged can be miniaturized in a predetermined direction.

In the drive unit on the eighth side according to any one of the fifth to seventh sides of the present disclosure, the third bearing includes a radial bearing.
According to the drive unit on the eighth side surface, it is possible to reduce the power loss due to the rotation of the output unit.

In the drive unit on the ninth side surface according to any one of the fifth to eighth sides of the present disclosure, a seal member arranged adjacent to the third bearing is further provided, and the seal member and the third bearing are provided with each other. A part of the base portion is arranged between them.
According to the drive unit on the ninth side surface, the seal member is prevented from being crushed by the third bearing.

In the drive unit on the tenth side according to any one of the fifth to ninth sides of the present disclosure, the speed reducer has a fourth tooth portion that meshes with the third tooth portion and is provided on the output portion. The third bearing is provided between the connection portion and the fourth gear in the predetermined direction including the fourth gear.
According to the drive unit on the tenth side surface, since the third bearing is provided between the portion of the output unit where the rotational force is input and the portion where the rotational force is output, the output unit is stably supported. To.

In the drive unit on the eleventh side surface according to the tenth side surface of the present disclosure, the input rotation shaft provided on the base portion, extending in the predetermined direction and inputting the human-powered driving force, the fourth gear, and the output portion. A one-way clutch provided between the two is further provided, and the input rotation shaft is connected to the output unit so as to transmit a human-powered driving force to the output unit when the input rotation shaft rotates at least in a predetermined first rotation direction. The one-way clutch allows relative rotation between the input rotation shaft and the fourth gear when the input rotation shaft rotates in the predetermined first rotation direction and the motor is stopped. It is configured as follows.
According to the drive unit on the eleventh side surface, when the input rotation shaft is rotated in the predetermined first rotation direction while the motor is stopped, the transmission of the driving force from the input rotation shaft to the fourth gear is suppressed. Therefore, the loss of human-powered driving force can be suppressed.

The drive unit on the twelfth side according to any one of the second to tenth sides of the present disclosure is further provided with an input rotation shaft provided on the base portion, extending in the predetermined direction, and inputting a human-powered driving force. The input rotation shaft is connected to the output unit so as to transmit a human-powered driving force to the output unit when rotating at least in a predetermined first rotation direction.
According to the drive unit on the twelfth side surface, the output unit can be rotated by rotating the input rotation axis in a predetermined direction by a human-powered driving force.

In the drive unit on the thirteenth side according to the eleventh or the twelfth side surface of the present disclosure, the input rotation shaft and the output unit are provided coaxially.
According to the drive unit on the thirteenth side, the drive unit can be miniaturized.

In the drive unit on the 14th side according to the 13th side of the present disclosure, the output unit is configured to rotate integrally with the input rotation shaft.
According to the drive unit on the 14th side surface, the loss of human-powered driving force between the input rotation shaft and the output unit can be reduced.

In the drive unit on the fifteenth side according to any one of the first to the fourteenth sides of the present disclosure, more than half of the portion of the first bearing in the predetermined direction is the second tooth in the radial direction of the second gear. It is placed inside the part.
According to the drive unit on the fifteenth side surface, the size can be further reduced in the direction in which the reduction shaft extends.

In the drive unit on the 16th side according to any one of the 1st to 15th sides of the present disclosure, the first bearing includes a radial bearing, and the second bearing includes a radial bearing.
According to the drive unit on the 16th side surface, it is possible to reduce the power loss due to the rotation of the reduction shaft.

The drive unit for a human-powered vehicle of the present disclosure can be miniaturized in the direction in which the reduction shaft extends.

A side view of a human-powered vehicle including a drive unit for the human-powered vehicle of the embodiment. The perspective view of the drive unit for the human power drive vehicle of an embodiment. FIG. 2 is a first side view of the drive unit for a human-powered vehicle of FIG. 2 in the first rotation direction. The second side view in the 1st direction of the drive unit for the human power drive vehicle of FIG. FIG. 2 is a plan view of a drive unit for a human-powered vehicle of FIG. A side view of the state where the cover portion is removed from FIG. FIG. 3 is a cross-sectional view taken along the line D7-D7 of FIG.

<Embodiment>
A drive unit 40 for a human-powered vehicle according to an embodiment will be described with reference to FIGS. 1 to 7. The human-powered vehicle 10 is a vehicle having at least one wheel and can be driven by at least human-powered driving force. The human-powered vehicle 10 includes various types of bicycles such as mountain bikes, road bikes, city bikes, cargo bikes, and hand bikes and recumbent bikes. The number of wheels of the human-powered vehicle 10 is not limited. The human-powered vehicle 10 also includes, for example, a one-wheeled vehicle and a vehicle having three or more wheels. The human-powered vehicle 10 is not limited to a vehicle that can be driven only by human-powered driving force. The human-powered vehicle 10 includes an e-bike that uses not only the human-powered driving force but also the driving force of an electric motor for propulsion. E-bikes include electrically power assisted bicycles that are assisted by electric motors. Hereinafter, in the embodiment, the human-powered vehicle 10 will be described as an electrically assisted bicycle, and an example of the electrically assisted bicycle will be described as a road bike.

The human-powered vehicle 10 includes a crank 12 to which a human-powered driving force is input. The human-powered vehicle 10 further includes at least one wheel 14 and a vehicle body 16. At least one wheel 14 includes a rear wheel 14A and a front wheel 14B. The vehicle body 16 includes a frame 18. The crank 12 includes an input rotating shaft 56 rotatable with respect to the frame 18 and a pair of crank arms 12A provided at the axial ends of the input rotating shaft 56, respectively. In the present embodiment, the input rotation shaft 56 is a crank shaft. A pair of pedals 20 are connected to each crank arm 12A. The rear wheel 14A is driven by the rotation of the crank 12. The rear wheel 14A is supported by the frame 18. The crank 12 and the rear wheel 14A are connected by a drive mechanism 22. The drive mechanism 22 includes a rotating body 24 connected to the input rotating shaft 56. The rotating body 24 includes a sprocket, a pulley, or a bevel gear. The rotating body 24 is connected to the rear wheel 14A via a connecting member. Connecting members include, for example, chains, belts, or shafts.

The human-powered vehicle 10 may include a front derailleur. When the human-powered vehicle 10 includes a front derailleur, the rotating body 24 may include a plurality of sprockets. A front wheel 14B is attached to the frame 18 via a front fork 30. A handlebar is connected to the front fork 30 via a stem. In the present embodiment, the rear wheel 14A is connected to the crank 12 by the drive mechanism 22, but at least one of the rear wheel 14A and the front wheel 14B may be connected to the crank 12 by the drive mechanism 22.

Preferably, the human-powered vehicle 10 further includes a battery 36. The battery 36 includes one or more battery elements. The battery element includes a rechargeable battery. The battery 36 is configured to supply power to the drive unit 40. The battery 36 is preferably communicably connected to the drive unit 40 via an electrical cable or wireless communication device. The battery 36 can communicate with the drive unit 40 by, for example, power line communication (PLC), CAN (Controller Area Network), or UART (Universal Asynchronous Receiver / Transmitter).

The drive unit 40 includes a base portion 42, a motor 44, and a speed reducer 46. The base portion 42 constitutes, for example, the housing of the drive unit 40. The base portion 42 is provided on the frame 18. The base portion 42 is detachably attached to the frame 18, for example. The base portion 42 has at least one mounting portion 42A. At least one mounting portion 42A is provided on the outer peripheral portion of the base portion 42. At least one mounting portion 42A comprises at least one of a hole and a female thread, respectively. Preferably, the hole and the female thread portion extend in a direction parallel to the rotation axis CA of the input rotation axis 56. The base 42 is attached to the frame 18 by engaging the bolts with at least one attachment 42A and the frame 18.

At least one mounting portion 42A is provided on the first side wall portion 40A of the base portion 42 and the second side wall portion 40B of the base portion 42, respectively, in the direction in which the rotation axis CA of the input rotation shaft 56 extends. Preferably, the first side wall portion 40A is provided with three mounting portions 42A. Preferably, the second side wall portion 40B is provided with two mounting portions 42A. Preferably, two of the three mounting portions 42A provided on the first side wall portion 40A are two mountings provided on the second side wall portion 40B when viewed from a direction parallel to the rotation axis CA of the input rotation shaft 56. It is arranged at a position overlapping each of the portions 42A. The three mounting portions 42A provided on the first side wall portion 40A are arranged at intervals around the rotation axis CA of the input rotation shaft 56. Preferably, the three mounting portions 42A of the first side wall portion 40A are located in a triangular region connecting the centers of the three mounting portions 42A when viewed from a direction parallel to the rotation axis CA of the input rotation shaft 56. Is provided on the first side wall portion 40A so that the rotation axis CA of the above is arranged.

Preferably, the base portion 42 includes a first housing 42X and a second housing 42Y. The first housing 42X includes a first side wall portion 40A of the base portion 42. The second housing 42Y includes a second side wall portion 40B of the base portion 42. The first housing 42X and the second housing 42Y are attached to each other by, for example, bolts or the like. The first housing 42X and the second housing 42Y form a storage space 42Z. The motor 44 is arranged in the accommodation space 42Z. In this embodiment, the base portion 42 is made of metal. The metal forming the base portion 42 includes, for example, an aluminum alloy or a magnesium alloy. The base portion 42 may be formed of a synthetic resin.

The motor 44 is provided on the base portion 42 and is configured to apply propulsive force to the human-powered vehicle 10. The motor 44 includes an electric motor. The electric motor is, for example, a brushless motor. The motor 44 is configured to transmit a rotational force to the rotating body 24.

The motor 44 has an output shaft 48, a rotor 50, and a stator 52. The output shaft 48 extends in a predetermined direction A and has a free end at the first end 48A of the predetermined direction A. The rotor 50 is fixed to the output shaft 48. The stator 52 faces the rotor 50. The output shaft 48 includes a second end 48B opposite to the first end 48A in a predetermined direction A. Of the predetermined directions A, the direction from the first end 48A of the output shaft 48 toward the second end 48B is defined as the first direction A1. Of the predetermined directions A, the direction from the second end 48B of the output shaft 48 toward the first end 48A is defined as the second direction A2. Preferably, the motor 44 is a radial gap type motor. Preferably, the motor 44 is an inner rotor type motor. The motor 44 may be an outer rotor type motor. The motor 44 may be an axial gap type motor. The first end portion 48A faces the inner surface of the first side wall portion 40A of the base portion 42. A gap is formed between the first end portion 48A and the inner surface of the first side wall portion 40A of the base portion 42. In the predetermined direction A, the distance between the first end portion 48A and the inner surface of the first side wall portion 40A of the base portion 42 is 1 mm or more and 10 mm or less, preferably 1 mm or more and 5 mm or less.

The motor 44 further includes at least one motor bearing 45. At least one motor bearing 45 includes a first motor bearing 45A and a second motor bearing 45B. The first motor bearing 45A rotatably supports an intermediate portion between the first end 48A of the output shaft 48 in the predetermined direction A and the second end 48B of the output shaft 48 in the predetermined direction A. .. The second motor bearing 45B rotatably supports the second end 48B of the output shaft 48 in a predetermined direction A. Preferably, the first motor bearing 45A includes a radial bearing. Preferably, the second motor bearing 45B includes a radial bearing. The first motor bearing 45A includes an inner ring, an outer ring, and a plurality of rolling elements arranged between the inner ring and the outer ring. The second motor bearing 45B includes an inner ring, an outer ring, and a plurality of rolling elements arranged between the inner ring and the outer ring. The inner diameter of the inner ring of the first motor bearing 45A is larger than the inner diameter of the inner ring of the second motor bearing 45B. The outer diameter of the outer ring of the first motor bearing 45A is larger than the outer diameter of the outer ring of the second motor bearing 45B. The first motor bearing 45A is supported by a recess 43A formed on the inner surface portion of the second side wall portion 40B.

In the present embodiment, a part of the rotor 50 is arranged between the first motor bearing 45A and the second motor bearing 45B in the predetermined direction A. The outer diameter of the portion of the output shaft 48 where the rotor 50 is provided is smaller than the outer diameter of the portion where the first motor bearing 45A is provided. Positioning of the output shaft 48 where the first motor bearing 45A is provided and the portion where the first motor bearing 45A is provided are in contact with the inner ring of the first motor bearing 45A from the downstream side of the first direction A1. A part is provided. The outer diameter of the positioning portion is larger than the outer diameter of the portion where the first motor bearing 45A is provided. In the present embodiment, at least a part of the first motor bearing 45A and at least a part of the second motor bearing 45B are arranged between the inner peripheral surface of the stator 52 formed in an annular shape and the output shaft 48, respectively. Ru.

The speed reducer 46 is provided on the base portion 42 and is configured to transmit the driving force of the motor 44 to the rotating body 24. Preferably, the drive unit 40 further includes an output unit 54. The speed reducer 46 is arranged in the accommodation space 42Z of the base portion 42. The output unit 54 has a connection unit 54A to which the rotating body 24 is connected, and is connected to the speed reducer 46. The output unit 54 is configured to rotate around a rotation axis C1 extending in a predetermined direction A.

Preferably, the drive unit 40 further comprises an input rotation shaft 56. The input rotation shaft 56 is provided on the base portion 42 and extends in a predetermined direction A, and a human-powered driving force is input. The input rotation shaft 56 is connected to the output unit 54 so as to transmit a human-powered driving force to the output unit 54 when rotating at least in the predetermined first rotation direction R1. Preferably, the input rotation shaft 56 and the output unit 54 are provided coaxially. Preferably, it is provided on the outer peripheral portion of the input rotation shaft 56. The input rotation shaft 56 is preferably made of metal. In this embodiment, the input rotation shaft 56 is formed by a hollow shaft. The input rotation shaft 56 may be formed by a solid shaft.

A first hole 42B and a second hole 42C are formed in the base portion 42. The first hole 42B is formed in the first side wall portion 40A. The second hole 42C is formed in the second side wall portion 40B. The input rotation shaft 56 has a first end portion 56A and a second end portion 56B in the extending direction of the input rotation shaft 56. The input rotation shaft 56 passes through the first hole 42B and the second hole 42C, and projects from the accommodation space 42Z of the base portion 42 to the outside of the base portion 42. The first end portion 56A is exposed to the outside of the base portion 42 from the first hole 42B. The second end portion 56B is exposed to the outside of the base portion 42 from the second hole 42C.

At least a portion of the output portion 54 is arranged around the first end portion 56A. At least a part of the output portion 54 is arranged in the first hole 42B, and the connection portion 54A is exposed to the outside of the base portion 42. The output unit 54 has a substantially cylindrical shape. Preferably, the output unit 54 is made of metal. The connection portion 54A is provided at the first end portion 54C of the output portion 54 in a predetermined direction A. The connecting portion 54A is provided on the outer peripheral portion of the first end portion 54C. The connection portion 54A has, for example, a spline groove. A lock ring that regulates the movement of the rotating body 24 in a predetermined direction A is coupled to the inner peripheral portion of the first end portion 54C in a state where the rotating body 24 is connected to the connecting portion 54A. A female screw is formed. The first end portion 54C of the output portion 54 passes through the first hole 42B formed in the base portion 42 and projects outward from the accommodation space 42Z of the base portion 42. Preferably, the connecting portion 54A is arranged outside the housing included in the base portion 42.

Preferably, the output unit 54 is configured to rotate integrally with the input rotation shaft 56. The output unit 54 is configured to rotate integrally with the input rotation shaft 56 at least when the input rotation shaft 56 rotates in a predetermined first rotation direction R1. The output unit 54 is configured to rotate integrally with the input rotation shaft 56 at least when the input rotation shaft 56 rotates in a predetermined first rotation direction R1. In the present embodiment, when the input rotation shaft 56 rotates in the predetermined first rotation direction R1, the output unit 54 rotates integrally with the input rotation shaft 56 and the input rotation shaft 56 rotates in the predetermined first rotation. Even when rotating in a predetermined second rotation direction R2 opposite to the direction R1, it rotates integrally with the input rotation shaft 56.

For example, one of the outer peripheral portion of the input rotating shaft 56 and the inner peripheral portion of the output portion 54 has at least one convex portion, and the other of the outer peripheral portion of the input rotating shaft 56 and the inner peripheral portion of the output portion 54 is at least one. It has at least one recess that engages one protrusion. In the present embodiment, the first serration is formed on the outer peripheral portion of the input rotation shaft 56, and the second serration that fits with the first serration is formed on the inner peripheral portion of the output portion 54. The first serration may be press-fitted into the second serration or may be fixed by an adhesive.

The speed reducer 46 is configured to reduce the rotational speed of the motor 44 in two or more stages and transmit the driving force of the motor 44 to the rotating body 24. In the present embodiment, the speed reducer 46 is configured to reduce the rotation speed of the motor 44 in two stages and transmit the driving force of the motor 44 to the rotating body 24. The speed reducer 46 has a first tooth portion 58, a reduction shaft 60, at least one bearing 62, a second gear 64, and a third gear 66. The first tooth portion 58 is provided at the first end portion 48A of the output shaft 48. The reduction shaft 60 extends substantially parallel to the predetermined direction A. The second gear 64 has a second tooth portion 64A that meshes with the first tooth portion 58 on the outer peripheral portion, and is provided on the reduction shaft 60. The third gear 66 has a third tooth portion 66A on the outer peripheral portion and is provided on the reduction shaft 60, and the rotational force of the second gear 64 is transmitted. In the predetermined direction A, the third tooth portion 66A is arranged at a position closer to the rotor 50 and the stator 52 than the second tooth portion 64A. The second gear 64 has a diameter larger than the diameter of the third gear 66.

The second gear 64 has a diameter larger than the diameter of the first tooth portion 58. Therefore, the rotation speed of the second gear 64 is lower than the rotation speed of the first tooth portion 58. The first tooth portion 58 and the second tooth portion 64A may form a spur gear or a helical gear. Preferably, the speed reducer 46 has a fourth tooth portion 68A that meshes with the third tooth portion 66A, and further includes a fourth gear 68 provided in the output portion 54. The fourth gear 68 has a diameter larger than the diameter of the third gear 66. Therefore, the rotation of the third gear 66 is decelerated and transmitted to the fourth gear 68. The third tooth portion 66A and the fourth tooth portion 68A may form a spur gear or a helical gear.

The first tooth portion 58 is configured to rotate integrally with the output shaft 48. Preferably, the first tooth portion 58 is formed integrally with the output shaft 48 as a single member. Preferably, the first tooth portion 58 is formed so as to reach the end surface 48C of the first end portion 48A of the output shaft 48 in the predetermined direction A. The output shaft 48 is made of metal. When the first tooth portion 58 is integrally formed with the output shaft 48 as a single member, the output shaft 48 is processed to form the first tooth portion 58. When the output shaft 48 is machined by cutting, for example, to form the first tooth portion 58, the output shaft 48 is cut from the end surface 48C of the output shaft 48 toward the second end portion 48B in the predetermined direction A. When cutting the output shaft 48 from the end surface 48C of the output shaft 48 toward the second end 48B in the predetermined direction A, the cutting groove is cut at the end of the cutting groove on the second end 48B side in the predetermined direction A. It is preferable to gradually make it shallower. The strength of the output shaft 48 can be ensured by gradually making the cutting groove shallower at the end portion of the drilling groove on the second end portion 48B side in the predetermined direction A. Of the cutting grooves, the portion where the cutting groove gradually becomes shallow cannot be used as the first tooth portion 58. By forming the first tooth portion 58 on the first end portion 48A of the output shaft 48, the portion where the cutting groove gradually becomes shallow is formed with the first tooth portion 58 and the rotor 50 necessary for arranging the third tooth portion 66A. It can be placed in the middle part between. By forming the first tooth portion 58 on the output shaft 48, the number of parts can be reduced as compared with the case where the first tooth portion 58 is provided separately from the output shaft 48 and attached to the output shaft 48.

The first tooth portion 58 may be formed separately from the output shaft 48 and fixed to the first end portion 48A of the output shaft 48. When the first tooth portion 58 is formed separately from the output shaft 48, the first tooth portion 58 may be formed of metal or synthetic resin.

In the present embodiment, the second gear 64 is configured to rotate integrally with the reduction shaft 60. Preferably, the second gear 64 is formed separately from the reduction shaft 60 and fixed to the reduction shaft 60. For example, the reduction shaft 60 is made of metal. Preferably, the second gear 64 is made of synthetic resin. The second gear 64 may be made of metal. The second gear 64 may be integrally formed with the reduction shaft 60 as a single member. In the present embodiment, the third gear 66 is configured to rotate integrally with the reduction shaft 60. Preferably, the third gear 66 is formed integrally with the reduction shaft 60. The third gear 66 may be formed separately from the reduction shaft 60 and fixed to the reduction shaft 60. The third gear 66 may be formed of synthetic resin or metal. Preferably, the reduction shaft 60 is formed hollow. The reduction shaft 60 may be solidly formed.

Preferably, the fourth gear 68 is formed separately from the output unit 54 and attached to the output unit 54. Preferably, the fourth gear 68 is made of metal. The fourth gear 68 may be formed of synthetic resin. The fourth gear 68 is arranged so that a part of the fourth gear 68 overlaps the stator 52 when viewed from a predetermined direction A.

Preferably, the connecting portion 54A of the output portion 54 is arranged at a position closer to the second gear 64 than the third gear 66 in the predetermined direction A. In the first direction A1, the third gear 66 is arranged adjacent to the downstream side of the second gear 64. At least a part of the connecting portion 54A of the output portion 54 is arranged at a position farther from the rotor 50 and the stator 52 than the second gear 64 in the predetermined direction A.

In the present embodiment, when viewed from a direction parallel to the predetermined direction A, the output shaft 48, the reduction shaft 60, and the output unit 54 are the rotation axis C2 of the output shaft 48, the rotation axis C3 of the reduction shaft 60, and the output unit 54. , The rotation axis C1 of the output unit 54 is arranged substantially on a straight line. When viewed from a direction parallel to the predetermined direction A, the output shaft 48, the reduction shaft 60, and the output unit 54 are the rotation axis C2 of the output shaft 48, the rotation axis C3 of the reduction shaft 60, and the output unit 54. The rotation axis C1 may be arranged so as to be the apex of each triangle.

For example, the distance from the rotation axis C2 of the output shaft 48 to the rotation axis C3 of the reduction shaft 60 is shorter than the distance from the rotation axis C3 of the reduction shaft 60 to the rotation axis C1 of the output unit 54. When viewed from a direction parallel to the predetermined direction A, the reduction shaft 60 is arranged at a position overlapping with at least one of the rotor 50 and the stator 52. When viewed from a direction parallel to the predetermined direction A, the second gear 64 is arranged at a position overlapping with at least one of the rotor 50 and the stator 52. When viewed from a direction parallel to the predetermined direction A, the third gear 66 is arranged at a position overlapping with at least one of the rotor 50 and the stator 52.

At least one bearing 62 supports the reduction shaft 60. At least one bearing 62 of the speed reducer 46 has a first bearing 62A and a second bearing 62B located closer to the rotor 50 and the stator 52 than the first bearing 62A in a predetermined direction A. Preferably, the first bearing 62A supports the first end 60A of the reduction shaft 60 in a predetermined direction A. Preferably, the second bearing 62B supports the second end 60B of the reduction shaft 60 in a predetermined direction A.

Preferably, the first bearing 62A includes a radial bearing. Preferably, the second bearing 62B includes a radial bearing. Preferably, the first bearing 62A is a ball bearing or a roller bearing. The first bearing 62A includes an inner ring, an outer ring, and a plurality of rolling elements arranged between the inner ring and the outer ring. For example, the inner ring of the first bearing 62A is fixed to the reduction shaft 60, and preferably the inner ring of the first bearing 62A is press-fitted into the reduction shaft 60. Preferably, the outer ring of the first bearing 62A is gap-fitted in the first recess 43B formed in the base portion 42. The first bearing 62A may be a slide bearing. Preferably, the second bearing 62B is a ball bearing or a roller bearing. The second bearing 62B includes an inner ring, an outer ring, and a plurality of rolling elements arranged between the inner ring and the outer ring. For example, the inner ring of the second bearing 62B is fixed to the reduction shaft 60, and the outer ring of the second bearing 62B is held by the base portion 42. Preferably, the inner ring of the second bearing 62B is press-fitted into the reduction shaft 60. Preferably, the outer ring of the second bearing 62B is gap-fitted in the second recess 43C formed in the base portion 42. The second bearing 62B may be a slide bearing. The second recess 43C is formed in the inner wall portion 40C of the base portion 42. In the present embodiment, the outer diameter of the outer ring of the first bearing 62A and the outer diameter of the outer ring of the second bearing 62B are larger than the diameter of the third gear 66. In the present embodiment, the outer diameter of the outer ring of the first bearing 62A is equal to the outer diameter of the outer ring of the second bearing 62B. In the present embodiment, the inner diameter of the inner ring of the first bearing 62A is smaller than the inner diameter of the inner ring of the second bearing 62B.

At least a part of the first bearing 62A is arranged inside the second tooth portion 64A in the radial direction of the second gear 64. Preferably, a portion of more than half of the first bearing 62A in the predetermined direction A is arranged inside the second tooth portion 64A in the radial direction of the second gear 64. The second gear 64 includes a central portion 64E attached to the reduction shaft 60, an outer peripheral portion 64F provided with the second tooth portion 64A, and an intermediate portion 64B connecting the central portion 64E and the outer peripheral portion 64F. In the present embodiment, a female screw is formed on the inner peripheral surface of the central portion 64E. A male screw to which the female screw of the central portion 64E is connected is formed in the portion of the reduction shaft 60 to which the central portion 64E is fixed. When the motor 44 is driven so as to apply a propulsive force to the human-powered vehicle 10, a force is applied to the second gear 64 in the direction in which the second gear 64 is coupled to the reduction shaft 60 due to the rotational force of the output shaft 48. ..

The width L1 of the central portion 64E in the predetermined direction A and the width L2 of the intermediate portion 64B in the predetermined direction A are smaller than the width L3 of the outer peripheral portion 64F in the predetermined direction A. The width L1 of the central portion 64E in the predetermined direction A is smaller than the width L2 of the intermediate portion 64B in the predetermined direction A. The width L1 of the central portion 64E in the predetermined direction A may be equal to the width L2 of the intermediate portion 64B in the predetermined direction A. Preferably, the width L1 is 1/5 or more and 2/3 or less of the width L3. Preferably, the width L1 is 1/5 or more and 2/3 or less of the width L2. The central portion 64E of the second gear 64 may be formed of metal. When the central portion 64E of the second gear 64 is formed of metal and the central portion 64E and the outer peripheral portion 64F are formed of synthetic resin, the central portion 64E is insert-molded into the central portion 64E. The central portion 64E may be fixed to the reduction shaft 60 by press fitting. Even if at least one of a concave portion and a convex portion is formed in the central portion 64E and the portion of the reduction shaft 60 where the central portion 64E is formed so as to prevent the relative rotation between the second gear 64 and the reduction shaft 60. good.

The second tooth portion 64A is formed on the outer peripheral portion 64F of the second gear 64. A first arrangement space 42W in which at least a part of the first bearing 62A is arranged is formed between the inner peripheral surface of the outer peripheral portion 64F and the reduction shaft 60. At least a part of the base portion 42 is also arranged in the first arrangement space 42W. At least a part of the first recess 43B of the base portion 42 is arranged in the first arrangement space 42W. In the predetermined direction A, the entire first bearing 62A may be arranged in the first arrangement space 42W.

The base portion 42 includes an inner wall portion 40C arranged between the first side wall portion 40A and the second side wall portion 40B in a predetermined direction A. The inner wall portion 40C is arranged in the accommodation space 42Z. The inner wall portion 40C is formed so as to be divided into a first accommodation space in which the accommodation space 42Z rotor and the stator are arranged and a second accommodation space in which the speed reducer 46 is arranged. The inner wall portion 40C is formed separately from the first housing 42X and the second housing 42Y. The inner wall portion 40C is detachably fixed to the second housing 42Y by, for example, a bolt. A through hole 40D through which the output shaft 48 of the motor 44 passes is formed in the inner wall portion 40C. The first motor bearing 45A is supported by the recess 43D formed in the inner wall portion 40C. A through hole 40D is formed in the recess 43D. The outer ring of the first motor bearing 45A contacts the inner wall portion 40C from the downstream side of the first direction A1.

Preferably, the drive unit 40 further comprises a third bearing 70. The third bearing 70 is provided on the base portion 42 and rotatably supports the output portion 54. Preferably, the third bearing 70 includes a radial bearing. Preferably, the third bearing 70 is a ball bearing or a roller bearing. The third bearing 70 includes an inner ring, an outer ring, and a plurality of rolling elements arranged between the inner ring and the outer ring. For example, the inner ring of the third bearing 70 is fixed to the output portion 54, and the outer ring of the third bearing 70 is held by the base portion 42. Preferably, the inner ring of the third bearing 70 is press-fitted into the output unit 54. Preferably, the outer ring of the third bearing 70 is gap-fitted in the third recess 43E formed in the base portion 42. The third bearing 70 may be a slide bearing.

The second gear 64 includes a first end face 64C and a second end face 64D in a predetermined direction A. In the present embodiment, the end face on the upstream side of the first direction A1 of the second gear 64 is referred to as the first end face 64C, and the end face of the second gear 64 on the downstream side of the first direction A1 is referred to as the second end face 64D. Preferably, the first plane S1 including the first end surface 64C and perpendicular to the predetermined direction A and the second plane S2 including the second end surface 64D and perpendicular to the predetermined direction S2. At least a part of the three bearings 70 is arranged. Preferably, the third bearing 70 is entirely arranged between the first plane S1 and the second plane S2. A cylindrical member 57 is provided between the intermediate portion of the output unit 54 between the first end portion 54C of the output unit 54 and the second end portion 54B of the output unit 54 and the input rotation shaft 56. May be good. The tubular member 57 includes a sleeve or needle bearing. The tubular member 57 comes into contact with the inner peripheral surface of the intermediate portion of the output portion 54 and the outer peripheral surface of the input rotation shaft 56. At least a part of the tubular member 57 is arranged between the first plane S1 and the second plane S2. At least a part of the tubular member 57 is arranged at least radially inside the third bearing 70. At least a part of the tubular member 57 is arranged inside the fourth gear 68 in the radial direction.

Preferably, the drive unit 40 further comprises a seal member 72 that is disposed adjacent to the third bearing 70. Preferably, a part of the base portion 42 is arranged between the seal member 72 and the third bearing 70. The third recess 43E includes an inner peripheral surface 43X that contacts the outer peripheral surface of the outer ring of the third bearing 70, and a first side surface portion 43Y that is arranged between the third bearing 70 and the seal member 72A. For example, the outer ring of the third bearing 70 comes into contact with the first side surface portion 43Y from the downstream side of the first direction A1. The inner peripheral surface of the first side wall portion 40A defines the first hole 42B. The inner diameter of the first hole 42B is slightly larger than the outer diameter of the portion of the output portion 54 facing the first hole 42B. The seal member 72 is arranged between the base portion 42 and the output portion 54. The seal member 72 has elasticity. The seal member 72 is formed of, for example, rubber. The seal member 72 is formed in a substantially annular shape. The outer peripheral portion of the seal member 72 is fixed to the base portion 42. For example, the outer peripheral portion of the seal member 72 is press-fitted into the fourth recess 43F formed in the base portion 42. The inner peripheral portion of the seal member 72 comes into contact with the outer peripheral surface of the output portion 54. Since the seal member 72 is fixed to the base portion 42 from the outside of the first housing 42X, it can be easily attached and replaced. The seal member 72 suppresses foreign matter from entering the accommodation space 42Z from the first hole 42B. Preferably, in a predetermined direction A, the third bearing 70 is provided between the connecting portion 54A and the fourth gear 68.

Preferably, the drive unit 40 further comprises a fourth bearing 74. The fourth bearing 74 is provided on the base portion 42 and rotatably supports the second end portion 56B of the input rotating shaft 56. Preferably, the fourth bearing 74 includes a radial bearing. Preferably, the fourth bearing 74 is a ball bearing or a roller bearing. For example, the inner ring of the fourth bearing 74 is fixed to the input rotation shaft 56, and the outer ring of the fourth bearing 74 is held by the base portion 42. Preferably, the inner ring of the fourth bearing 74 is press-fitted into the input rotary shaft 56. Preferably, the outer ring of the fourth bearing 74 is gap-fitted into the fifth recess 43G formed in the base portion 42. The fourth bearing 74 may be a slide bearing.

Preferably, the drive unit 40 further comprises a seal member 72A disposed adjacent to the fourth bearing 74. Preferably, a part of the base portion 42 is arranged between the seal member 72A and the fourth bearing 74. The fifth recess 43G includes an inner peripheral surface 43V in contact with the outer peripheral surface of the outer ring of the fourth bearing 74, and a second side surface portion 43W arranged between the fourth bearing 74 and the seal member 72A.

Preferably, in a predetermined direction A, at least one of a leaf spring or a washer is provided between at least one of the outer ring of the fourth bearing 74 and the inner ring of the fourth bearing 74 and the second side surface portion 43W. At least one of the leaf springs or washers suppresses the rattling of the input rotation shaft 56 and the output unit 54 in the predetermined direction A. The inner peripheral surface of the second side surface portion 43W defines the second hole 42C. The inner diameter of the second hole 42C is slightly larger than the outer diameter of the portion of the input rotating shaft 56 facing the second hole 42C. The seal member 72A is arranged between the base portion 42 and the input rotation shaft 56. The seal member 72A has elasticity. The seal member 72A is formed of, for example, rubber. The seal member 72A is formed in a substantially annular shape. The outer peripheral portion of the seal member 72A is fixed to the base portion 42. For example, the outer peripheral portion of the seal member 72A is press-fitted into the sixth recess 43H formed in the base portion 42. The inner peripheral portion of the seal member 72A comes into contact with the outer peripheral surface of the input rotation shaft 56. Since the seal member 72A is fixed to the base portion 42 from the outside of the second housing 42Y, it can be easily attached and replaced.

Preferably, the drive unit 40 further includes a one-way clutch 78. The one-way clutch 78 is provided between the fourth gear 68 and the output unit 54. The one-way clutch 78 allows relative rotation between the input rotation shaft 56 and the fourth gear 68 when the input rotation shaft 56 rotates in the first rotation direction R1 predetermined and the motor 44 is stopped. It is composed of. The one-way clutch 78 includes, for example, at least one of a roller clutch, a sprag clutch, and a claw clutch. The one-way clutch 78 is provided, for example, between the inner peripheral portion of the fourth gear 68 and the output portion 54. The one-way clutch 78 includes an inner ring, an outer ring, and a plurality of rolling elements arranged between the inner ring and the outer ring. The outer ring of the one-way clutch 78 may be integrally formed with the fourth gear 68 as a single member. The inner ring of the one-way clutch 78 may be integrally formed with the output unit 54 as a single member. The inner ring and the outer ring of the one-way clutch 78 are formed of metal. Preferably, the plurality of rolling elements of the one-way clutch 78 are held by the carrier. The one-way clutch 78 is provided in an intermediate portion between the first end portion 54C and the second end portion 54B of the output unit 54 in a predetermined direction A.

Preferably, the drive unit 40 includes a control device 80. The control device 80 includes a control unit. The control unit includes an arithmetic processing unit that executes a predetermined control program. The arithmetic processing unit includes, for example, a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). The arithmetic processing units may be provided at a plurality of locations separated from each other. The control unit may include one or more microcomputers. Preferably, the control device 80 further includes a storage unit. Information used for various control programs and various control processes is stored in the storage unit. The storage unit includes, for example, a non-volatile memory and a volatile memory. The non-volatile memory includes, for example, at least one of a ROM (Read-Only Memory), an EPROM (Erasable Programmable Read Only Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), and a flash memory. Volatile memory includes, for example, RAM (Random access memory).

The control device 80 is arranged in the accommodation space 42Z. The control device 80 includes a circuit board 80A. The circuit board 80A is arranged in the accommodation space 42Z. The circuit board 80A is arranged in the first accommodation space. The circuit board 80A is arranged so that the mounting surface of the circuit board 80A is substantially orthogonal to the predetermined direction A. The circuit board 80A is arranged so that the circuit board 80A and at least a part of the stator 52 overlap each other when viewed from a predetermined direction A. The stator 52 includes a plurality of coils. The stator 52 includes a plurality of connection terminals to which a plurality of coils are electrically connected. The plurality of connection terminals extend along a predetermined direction A and are electrically connected to the circuit board 80A. In the predetermined direction A, at least a part of the circuit board 80A is arranged in the region between the second plane S2 and the inner wall portion 40C.

A control device 80, preferably a drive circuit for a motor 44, is further provided. The drive circuit and the control unit may be provided on the same circuit board 80A, for example. The drive circuit includes an inverter circuit. The drive circuit controls the electric power supplied from the battery 36 to the motor 44. The drive circuit is connected to the control unit via a conductive wire, an electric cable, a wireless communication device, or the like. The drive circuit drives the motor 44 in response to a control signal from the control unit.

Preferably, the drive unit 40 further includes a first sensor 86 that detects a human-powered driving force input to the crank 12. The first sensor 86 is arranged, for example, between the second end portion 54B of the output portion 54 and the one-way clutch 78 in the predetermined direction A. The first sensor 86 may include a strain sensor or may include a magnetostriction sensor. The strain sensor includes a strain gauge. The first sensor 86 is provided on the outer peripheral portion of the output portion 54 or around the outer peripheral portion. The first sensor 86 is connected to the control device 80 via a conductive wire, an electric cable, a wireless communication device, or the like. The first sensor 86 may be provided on one or both of the pair of crank arms 12A. When the first sensor 86 is provided on one or both of the pair of crank arms 12A, the first sensor 86 includes a strain sensor.

Preferably, the drive unit 40 further includes a second sensor that detects the rotational state of the crank 12. The second sensor outputs a signal according to the rotation of the input rotation shaft 56 or the output unit 54. The second sensor includes, for example, a magnetic sensor or an optical sensor. The second sensor is configured to detect the input rotation shaft 56 or the detected unit provided in the output unit 54. The detected portion is, for example, an annular member including an annular magnet or a slit. The second sensor is connected to the control device 80 via a conductive wire, an electric cable, a wireless communication device, or the like. The second sensor may be provided on the upstream side or the downstream side of the first sensor 86 in the first direction A1.

Preferably, the drive unit 40 further includes an electrical connector 82. The electric connector 82 is connected to the control device 80. The electrical connector 82 is configured to be connectable to, for example, at least one of an electrical cable connected to the battery 36 and an electrical cable connected to a component of a manpower vehicle. The electric connector 82 is provided, for example, on the outer surface of the second side wall portion 40B. Preferably, the drive unit 40 further comprises a cover 84 that covers at least a portion of the electrical connector 82. The cover portion 84 is attached to the outer surface of the second side wall portion 40B. The cover portion 84 has a hole 84A in which the second end portion 56B of the input rotation shaft 56 is arranged. The cover portion 84 is formed in a disk shape, for example.

<Modification example>
The description of the embodiments is an example of possible embodiments of a drive unit for a manpower driven vehicle according to the present disclosure, and is not intended to limit the embodiments. The drive unit for a human-powered vehicle according to the present disclosure may take, for example, a modification of the embodiment shown below and a combination of at least two modifications that do not contradict each other. In the following modification, the parts common to the embodiment are designated by the same reference numerals as those in the embodiment, and the description thereof will be omitted.

The output shaft 48 does not have to have a free end at the first end 48A in the predetermined direction A. In this case, the drive unit 40 is provided in the base portion 42, the motor 44 provided in the base portion 42 and configured to apply the propulsive force to the human-powered vehicle 10, and the drive unit 40 provided in the base portion 42 to drive the motor 44. A speed reducer 46 configured to transmit the above, and an output unit 54 having a connection part 54A to which the rotating body 24 is connected and connected to the speed reducer 46 are provided. The motor 44 has an output shaft 48 extending in a predetermined direction A, a rotor 50 fixed to the output shaft 48, and a stator 52 facing the rotor 50. The speed reducer 46 is provided on the first tooth portion 58 provided on the output shaft 48, the reduction shaft 60 extending in parallel with the predetermined direction A, the bearing 62 supporting the reduction shaft 60, and the reduction shaft 60. A second gear 64 having a second tooth portion 64A meshing with the tooth portion 58 on the outer peripheral portion and a second gear 64 provided on the reduction shaft 60 and having a third tooth portion 66A on the outer peripheral portion, the rotational force of the second gear 64 is transmitted. It has a third gear 66 and the like. The bearing 62 of the speed reducer 46 has a first bearing 62A and a second bearing 62B arranged at positions closer to the rotor 50 and the stator 52 than the first bearing 62A in a predetermined direction A. In the predetermined direction A, the second tooth portion 64A is arranged at a position closer to the rotor 50 and the stator 52 than the third tooth portion 66A. The second gear 64 has a diameter larger than the diameter of the third gear 66. At least a part of the first bearing 62A is arranged inside the second tooth portion 64A in the radial direction of the second gear 64. The output unit 54 is configured to rotate around a rotation axis extending in a predetermined direction A. The connecting portion 54A of the output portion 54 is arranged at a position closer to the second gear 64 than the third gear 66 in the predetermined direction A. For example, the first motor bearing 45A may be arranged so as to rotatably support the first end portion 48A instead of supporting the intermediate portion of the output shaft 48.

The reduction shaft 60 may be non-rotatably supported by the base portion 42. In this case, the bearing 62 non-rotatably supports the reduction shaft 60 with respect to the base portion 42. The second gear 64 and the third gear 66 are provided so that the second gear 64 and the third gear 66 rotate integrally and rotatably with respect to the reduction shaft 60.

The second gear 64 may be attached to the reduction shaft 60 via a one-way clutch. In this case, for example, the one-way clutch 78 is omitted, and a one-way clutch similar to the one-way clutch 78 is provided between the second gear 64 and the reduction shaft 60. When the one-way clutch 78 is omitted, the fourth gear 68 may be integrally formed with the output unit 54.

The third gear 66 may be attached to the reduction shaft 60 via a one-way clutch. In this case, for example, the one-way clutch 78 is omitted, and a one-way clutch similar to the one-way clutch 78 is provided between the third gear 66 and the reduction shaft 60.

The speed reducer 46 may be configured to reduce the rotational speed of the motor 44 in three or more stages and transmit the driving force of the motor 44 to the rotating body 24. In this case, for example, the speed reducer 46 has a fifth gear that meshes with the third gear 66 and a sixth gear, a fifth gear, and a fifth gear that mesh with the fourth gear 68 between the third gear 66 and the fourth gear 68. A speed reduction unit including a shaft member provided with a sixth gear is provided. The fifth gear rotates integrally with the sixth gear. The speed reducer 46 may include a speed reduction unit composed of a gear other than the gear between the third gear 66 and the fourth gear 68. The speed reducing unit composed of other than the gears includes, for example, a pulley and a belt. The speed reducer composed of other than the gears includes, for example, a sprocket and a chain.

A second one-way clutch may be provided between the input rotation shaft 56 and the output unit 54. In the second one-way clutch, when the input rotation shaft 56 rotates in the first rotation direction R1, a human-powered driving force is transmitted from the input rotation shaft 56 to the output unit 54, and the input rotation shaft 56 rotates in the first rotation direction R1. When rotating in the second rotation direction R2 opposite to that of the above, it is configured to allow relative rotation from the input rotation shaft 56 to the output unit 54. A second one-way clutch may be provided between the first end portion 54C and the second end portion 54B of the output unit 54. The output unit 54 may be formed by a single member, or may be formed by combining a plurality of members divided in a predetermined direction A. When the drive unit 40 is provided with the second one-way clutch, a third bearing 70 is provided between the outer peripheral portion of the first end portion 56A of the input rotating shaft 56 and the inner peripheral portion of the first end portion 54C of the output portion 54. Similar bearings are provided.

Two of the three mounting portions 42A provided on the first side wall portion 40A include, for example, the rotation axis CA of the input rotation shaft 56, the rotation axis CA of the input rotation shaft 56, and the output shaft 48 of the motor 44. It is provided between the fourth plane perpendicular to the third plane including the rotation axis C2 of the motor 44 and the fifth plane including the rotation axis C2 of the output shaft 48 of the motor 44 and perpendicular to the third plane. One of the three mounting portions 42A provided on the first side wall portion 40A is arranged, for example, in a region opposite to the region where the rotation axis C2 of the output shaft 48 of the motor 44 is arranged with respect to the fourth plane. To. One of the two mounting portions 42A provided on the second side wall portion 40B includes, for example, the rotation axis CA of the input rotation shaft 56, the rotation axis CA of the input rotation shaft 56, and the output shaft 48 of the motor 44. It is provided between a fourth plane perpendicular to the third plane including the rotation axis C2 and a fifth plane including the rotation axis C2 of the output shaft 48 of the motor 44 and perpendicular to the third plane. One of the two mounting portions 42A provided on the second side wall portion 40B is arranged, for example, in a region opposite to the region where the rotation axis C2 of the output shaft 48 of the motor 44 is arranged with respect to the fourth plane. To.

As used herein, the expression "at least one" means "one or more" of the desired choice. As an example, the expression "at least one" as used herein means "only one option" or "both two options" if the number of options is two. As another example, the expression "at least one" as used herein means "only one option" or "combination of two or more arbitrary options" if the number of options is three or more. means.

10 ... Human-powered vehicle, 24 ... Rotating body, 40 ... Drive unit, 42 ... Base, 44 ... Motor, 46 ... Reducer, 48 ... Output shaft, 48A ... First end, 50 ... Rotor, 52 ... Stator, 54 ... Output unit, 54A ... Connection unit, 56 ... Input rotation shaft, 58 ... 1st tooth part, 60 ... Deceleration shaft, 62 ... Bearing, 62A ... 1st bearing, 62B ... 2nd bearing, 64 ... 2nd gear, 64A ... 2nd tooth portion, 64C ... 1st end face, 64D ... 2nd end face, 66 ... 3rd gear, 66A ... 3rd tooth portion, 68 ... 4th gear, 70 ... 3rd bearing, 72 ... Seal member, 78 ... One-way clutch.

Claims (16)

It is a drive unit for human-powered vehicles.
With the base part
A motor provided on the base portion and configured to apply propulsive force to the human-powered vehicle,
A speed reducer provided on the base portion and configured to transmit the driving force of the motor to the rotating body is provided.
The motor is
An output shaft that extends in a predetermined direction and has a free end at the first end in the predetermined direction.
The rotor fixed to the output shaft and
It has a stator facing the rotor and
The reducer
A first tooth portion provided at the first end portion of the output shaft and
A deceleration axis extending substantially parallel to the predetermined direction,
With at least one bearing supporting the reduction shaft,
A second gear having a second tooth portion that meshes with the first tooth portion on the outer peripheral portion and provided on the reduction shaft,
It has a third tooth portion on the outer peripheral portion, is provided on the reduction shaft, and has a third gear to which the rotational force of the second gear is transmitted.
The at least one bearing of the reducer
With the first bearing
It has the rotor and the second bearing arranged at a position closer to the stator than the first bearing in the predetermined direction.
In the predetermined direction, the third tooth portion is arranged at a position closer to the rotor and the stator than the second tooth portion.
The second gear has a diameter larger than the diameter of the third gear and has a diameter larger than that of the third gear.
A drive unit in which at least a part of the first bearing is arranged inside the second tooth portion in the radial direction of the second gear. The drive unit according to claim 1, further comprising an output unit connected to the speed reducer and having a connection unit to which the rotating body is connected. The output unit is configured to rotate around a rotation axis extending in the predetermined direction.
The drive unit according to claim 2, wherein the connection portion of the output unit is arranged at a position closer to the second gear than the third gear in the predetermined direction. It is a drive unit for human-powered vehicles.
With the base part
A motor provided on the base portion and configured to apply propulsive force to the human-powered vehicle,
A speed reducer provided on the base portion and configured to transmit the driving force of the motor,
It has a connection part to which a rotating body is connected, and includes an output part connected to the speed reducer.
The motor is
An output shaft that extends in a predetermined direction,
The rotor fixed to the output shaft and
It has a stator facing the rotor and
The reducer
The first tooth portion provided on the output shaft and
A deceleration axis extending parallel to the predetermined direction,
With at least one bearing supporting the reduction shaft,
A second gear provided on the reduction shaft and having a second tooth portion on the outer peripheral portion that meshes with the first tooth portion.
It has a third gear provided on the reduction shaft, having a third tooth portion on the outer peripheral portion, and transmitting the rotational force of the second gear.
The at least one bearing of the reducer
With the first bearing
It has the rotor and the second bearing arranged at a position closer to the stator than the first bearing in the predetermined direction.
In the predetermined direction, the second tooth portion is arranged at a position closer to the rotor and the stator than the third tooth portion.
The second gear has a diameter larger than the diameter of the third gear and has a diameter larger than that of the third gear.
At least a part of the first bearing is arranged inside the second tooth portion in the radial direction of the second gear.
The output unit is configured to rotate around a rotation axis extending in the predetermined direction.
The connection portion of the output unit is a drive unit arranged at a position closer to the second gear than the third gear in the predetermined direction. The drive unit according to claim 3 or 4, further comprising a third bearing provided on the base portion and rotatably supporting the output portion. The second gear includes a first end face and a second end face in the predetermined direction.
The third bearing is located between a first plane containing the first end face and perpendicular to the predetermined direction and a second plane including the second end face and perpendicular to the predetermined direction. The drive unit according to claim 5, wherein at least a part thereof is arranged. The drive unit according to claim 6, wherein the third bearing is entirely arranged between the first plane and the second plane. The drive unit according to any one of claims 5 to 7, wherein the third bearing includes a radial bearing. Further provided with a sealing member disposed adjacent to the third bearing,
The drive unit according to any one of claims 5 to 8, wherein a part of the base portion is arranged between the seal member and the third bearing. The speed reducer has a fourth tooth portion that meshes with the third tooth portion, and further includes a fourth gear provided in the output portion.
The drive unit according to any one of claims 5 to 9, wherein the third bearing is provided between the connection portion and the fourth gear in the predetermined direction. An input rotation shaft provided on the base portion, extending in the predetermined direction, and input with a human-powered driving force,
Further, a one-way clutch provided between the fourth gear and the output unit is provided.
The input rotation shaft is connected to the output unit so as to transmit a human-powered driving force to the output unit when rotating at least in a predetermined first rotation direction.
The one-way clutch allows relative rotation between the input rotation shaft and the fourth gear when the input rotation shaft rotates in the predetermined first rotation direction and the motor is stopped. The drive unit according to claim 10. Further provided with an input rotation axis provided on the base portion, extending in the predetermined direction, and input with a human-powered driving force.
The invention according to any one of claims 2 to 10, wherein the input rotation shaft is connected to the output unit so as to transmit a human-powered driving force to the output unit when the input rotation shaft rotates at least in a predetermined first rotation direction. The drive unit described. The drive unit according to claim 11 or 12, wherein the input rotation shaft and the output unit are coaxially provided. 13. The drive unit according to claim 13, wherein the output unit is configured to rotate integrally with the input rotation shaft. The drive unit according to any one of claims 1 to 14, wherein a portion of one half or more of the first bearing in the predetermined direction is arranged inside the second tooth portion in the radial direction of the second gear. .. The first bearing includes a radial bearing.
The drive unit according to any one of claims 1 to 15, wherein the second bearing includes a radial bearing.

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