JP7779692B2 - Drive unit for human-powered vehicles - Google Patents

Description

This disclosure relates to a drive unit for a human-powered vehicle.

For example, in the drive unit disclosed in Patent Document 1, the position of the bearing relative to the support member in the axial direction of the rotating shaft is determined by a step formed in the support member, but gaps are likely to occur between the bearing and the support member.

Japanese Patent Application Laid-Open No. 2018-202949

The objective of this disclosure is to provide a drive unit for a human-powered vehicle that makes it easy to determine the position of the first bearing relative to the support member in the axial direction of the rotating shaft.

A drive unit according to a first aspect of the present disclosure is a drive unit for a human-powered vehicle, and comprises: a support member formed separately from the frame of the human-powered vehicle; a rotating shaft passing through the support member; at least one of an electric motor provided on the support member and configured to provide propulsive force to the human-powered vehicle; and a transmission provided on the support member and connected to the rotating shaft; a first bearing provided on the support member and rotatably supporting the rotating shaft with respect to the rotational center axis of the rotating shaft; and a first member provided on the support member so as to be movable in a first direction parallel to the rotational center axis and configured to position the first bearing relative to the support member in the first direction.
According to the drive unit of the first side surface, the first bearing can be suitably positioned relative to the support member in the first direction parallel to the central axis of rotation by the first member, making it easy to determine the position of the first bearing relative to the support member in the first direction parallel to the central axis of rotation.

In the drive unit of the second aspect according to the first aspect of the present disclosure, the rotating shaft includes at least one of a crankshaft and an output rotating shaft arranged coaxially with the crankshaft radially outside the crankshaft and to which rotational force input to the crankshaft is transmitted, and the first bearing directly supports the crankshaft or the output rotating shaft.
According to the drive unit of the second aspect, the crankshaft or the output rotating shaft can be favorably supported by the first bearing.

In a drive unit of a third aspect according to the first or second aspect of the present disclosure, the support member includes a housing that forms an accommodating space, and the first member is provided on the housing so as to be operable from outside the housing.
According to the drive unit of the third aspect, the first bearing can be suitably positioned relative to the support member in the first direction by operating the first member from outside the housing.

In a drive unit of a fourth aspect according to any one of the first to third aspects of the present disclosure, the first bearing includes an inner ring connected to the rotating shaft, an outer ring contacting the support member in the radial direction of the rotating shaft, and a plurality of rolling elements arranged between the inner ring and the outer ring, and the first member has an opposing surface facing a first end face of the outer ring in the first direction.
According to the drive unit of the fourth side surface, the opposing surface faces the first end surface, so that the first bearing can be suitably positioned relative to the support member in the first direction.

In the drive unit of the fifth aspect according to the fourth aspect of the present disclosure, the inner ring is press-fitted onto the rotating shaft.
According to the drive unit of the fifth aspect, the inner ring is press-fitted onto the rotating shaft, so that the first bearing is securely attached to the rotating shaft.

In a drive unit of a sixth aspect according to the fourth or fifth aspect of the present disclosure, the drive unit further includes a second bearing provided on the support member and rotatably supporting the rotating shaft with respect to the central axis of rotation, the second bearing being spaced apart from the first bearing in the first direction, and the first end face of the outer ring of the first bearing facing away from the second bearing in the first direction.
According to the drive unit of the sixth aspect, the rotating shaft can be favorably supported by the first bearing and the second bearing.

In a drive unit of a seventh aspect according to any one of the fourth to sixth aspects of the present disclosure, the first member has a first cylindrical portion arranged substantially coaxially with the central axis of rotation, and a first thread is formed on the first cylindrical portion, the support member has a second cylindrical portion arranged substantially coaxially with the central axis of rotation, and a second thread is formed on the second cylindrical portion that is coupled to the first thread, one of the first thread and the second thread is a male thread, and the other of the first thread and the second thread is a female thread.
According to the drive unit of the seventh aspect, by coupling the first screw of the first cylindrical portion and the second screw of the second cylindrical portion, the position of the first member relative to the support member can be suitably adjusted.

In the drive unit of the eighth aspect according to the seventh aspect of the present disclosure, the first member has a protrusion that protrudes from the inner surface of the first cylindrical portion toward the radially inward direction of the first cylindrical portion, and the protrusion has the opposing surface.
According to the drive unit of the eighth aspect, the protruding portion has an opposing surface, so that the opposing surface can be formed suitably.

The drive unit of a ninth aspect according to any one of the first to eighth aspects of the present disclosure further includes a second member that restricts movement of the first member relative to the support member in the first direction.
According to the drive unit of the ninth aspect, the second member can suitably restrict movement of the first member relative to the support member.

In a drive unit of a tenth aspect according to the seventh or eighth aspect of the present disclosure, a second member is further provided that restricts movement of the first member relative to the support member in the first direction, the second member having a third cylindrical portion, the third cylindrical portion having a third thread formed thereon that is coupled to the second screw, the first thread being a female thread, the second thread being a male thread, and the third thread being a female thread.
According to the drive unit of the tenth aspect, the position of the second member relative to the support member can be suitably adjusted by coupling the female threads of the first screw and the third screw to the male thread of the second screw. According to the drive unit of the tenth aspect, the configuration of the second member can be simplified because the female threads of the first screw and the third screw can be coupled to the male thread of the second screw.

In the drive unit of the eleventh aspect according to the seventh or eighth aspect of the present disclosure, a second member is further provided that restricts movement of the first member relative to the support member in the first direction, the second member having a third cylindrical portion, the third cylindrical portion having a third thread formed thereon that is coupled to the first screw, the first thread being a male thread, the second thread being a female thread, and the third thread being a female thread.
According to the drive unit of the eleventh aspect, the position of the second member relative to the support member can be suitably adjusted by coupling the female threads of the second screw and the third screw to the male thread of the first screw. According to the drive unit of the eleventh aspect, the configuration of the second member can be simplified because the female threads of the second screw and the third screw can be coupled to the male thread of the first screw.

In the drive unit of the twelfth aspect according to any one of the ninth to eleventh aspects of the present disclosure, the second member includes a second tool engagement portion that is capable of engaging a tool.
According to the drive unit of the twelfth aspect, the second member can be operated using a tool, making it easier to attach the second member to the support member.

In the drive unit of a thirteenth aspect according to any one of the first to twelfth aspects of the present disclosure, the first member includes a first tool engagement portion that is capable of engaging a tool.
According to the drive unit of the thirteenth aspect, the first member can be operated using a tool, making it easier to attach the first member to the support member.

In the drive unit of a fourteenth aspect according to any one of the first to thirteenth aspects of the present disclosure, the support member has a mounting portion that is attached to the frame of the human-powered vehicle.
According to the drive unit of the fourteenth aspect, the drive unit can be suitably attached to the frame.

The drive unit for a human-powered vehicle disclosed herein makes it easy to determine the position of the first bearing relative to the support member in the first direction parallel to the central axis of rotation.

1 is a perspective view of a drive unit for a human-powered vehicle according to a first embodiment. FIG. FIG. 2 is a side view of a drive unit for the human-powered vehicle of FIG. 1. FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. 2. FIG. 4 is an enlarged cross-sectional view of the first bearing and its surroundings in FIG. 3 . FIG. 10 is an enlarged cross-sectional view of a first bearing and its surrounding area of a drive unit for a human-powered vehicle according to a second embodiment.

First Embodiment
A drive unit 10 for a human-powered vehicle according to a first embodiment will be described with reference to FIGS. 1 to 4. Hereinafter, in the embodiments, the drive unit 10 for a human-powered vehicle will be referred to as the drive unit 10. A human-powered vehicle is a vehicle that has at least one wheel and can be propelled at least by human driving force. Human-powered vehicles include various types of bicycles, such as mountain bikes, road bikes, city bikes, cargo bikes, hand bikes, and recumbent bikes. The number of wheels a human-powered vehicle has is not limited. Human-powered vehicles also include, for example, unicycles and vehicles with two or more wheels. Human-powered vehicles are not limited to vehicles that can be propelled solely by human driving force. Human-powered vehicles include e-bikes that use not only human driving force but also the driving force of an electric motor 16 for propulsion. E-bikes include electrically assisted bicycles whose propulsion is assisted by an electric motor 16. Hereinafter, in the embodiments, the human-powered vehicle will be described as an electrically assisted bicycle.

The drive unit 10 includes a support member 12, a rotating shaft 14, at least one of an electric motor 16 and a transmission 18, a first bearing 20, and a first member 22. The drive unit 10 is attached to the frame of the human-powered vehicle.

The support member 12 is formed separately from the frame of the human-powered vehicle. For example, the support member 12 includes a housing 24 that defines an accommodation space 24A. The housing 24 is formed separately from the frame of the human-powered vehicle and attached to the frame of the human-powered vehicle. The housing 24 includes a first housing 26 and a second housing 28. The first housing 26 and the second housing 28 are arranged in a first direction X1. For example, the first direction X1 is a direction along the axial direction of the crankshaft 30. The first housing 26 and the second housing 28 are attached to each other by bolts 24B. The housing 24 includes a first hole 26A and a second hole 28A. The first hole 26A is provided in the first housing 26. The second hole 28A is provided in the second housing 28.

The accommodation space 24A is provided between the first housing 26 and the second housing 28. The accommodation space 24A accommodates at least one of the rotating shaft 14, the electric motor 16, and the transmission 18. For example, the accommodation space 24A accommodates a portion of the rotating shaft 14, the electric motor 16, and the transmission 18. The electric motor 16 may be configured so that at least a portion of the transmission 18 is accommodated in the accommodation space 24A.

For example, the support member 12 has an attachment portion 12A that is attached to the frame of the human-powered vehicle. For example, the support member 12 is detachably attached to the frame of the human-powered vehicle. The attachment portion 12A is provided on at least one of the first housing 26 and the second housing 28. For example, the support member 12 has a plurality of attachment portions 12A. The plurality of attachment portions 12A are arranged at intervals around the outer periphery of the drive unit 10. The attachment portion 12A includes a female thread portion 12B. The support member 12 is attached to the frame by a bolt that passes through the frame and is screwed into the female thread portion 12B. The attachment portion 12A may also be attached to the frame by a means other than the female thread portion 12B.

The rotating shaft 14 passes through the support member 12. The rotating shaft 14 passes through the first hole 26A and the second hole 28A. For example, the rotating shaft 14 includes at least one of a crankshaft 30 and an output rotating shaft 32. In this embodiment, the rotating shaft 14 includes both the crankshaft 30 and the output rotating shaft 32.

The crankshaft 30 passes through the first housing 26 and the second housing 28. The crankshaft 30 passes through the first hole 26A and the second hole 28A. The crankshaft 30 rotates in response to the human-powered driving force input to the human-powered vehicle. The crankshaft 30 is arranged substantially coaxially with the central rotation axis C1 of the rotating shaft 14. The crankshaft 30 includes a first end 30A, a second end 30B, and a central portion 30C relative to the first direction X1. A crank arm is provided at each of the first end 30A and the second end 30B. Pedals are attached to the crank arms to which human-powered driving force is input. When human-powered driving force is input to the pedals, the crankshaft 30 rotates.

For example, the output rotating shaft 32 is disposed coaxially with the crankshaft 30 and radially outward of the crankshaft 30 in the X2 direction, and transmits the rotational force input to the crankshaft 30. The output rotating shaft 32 passes through the second housing 28. The output rotating shaft 32 passes through the second hole 28A. The output rotating shaft 32 transmits the rotational force to the wheels of the human-powered vehicle via a front sprocket, a chain, and a rear sprocket. The output rotating shaft 32 is press-fitted into the crankshaft 30. The output rotating shaft 32 rotates integrally with the crankshaft 30. A one-way clutch may be provided between the crankshaft 30 and the output rotating shaft 32.

For example, the output rotating shaft 32 is provided with a detection unit 34 that detects the torque applied to the output rotating shaft 32. The detection unit 34 is, for example, a magnetostrictive sensor. The magnetostrictive sensor detects information related to the strain of the strain gauge. The strain gauge is provided on the outer periphery of the output rotating shaft 32.

The electric motor 16 is mounted on the support member 12 and configured to provide propulsive force to the human-powered vehicle. The electric motor 16 provides propulsive force to the human-powered vehicle in response to the human-powered driving force input to the human-powered vehicle. The torque of the electric motor 16 is transmitted to the output rotating shaft 32. The electric motor 16 includes an output shaft 16A. The electric motor 16 is a so-called brushless motor. In this embodiment, the output shaft 16A of the electric motor 16 is parallel to the crankshaft 30. The output shaft 16A of the electric motor 16 may also be perpendicular to the crankshaft 30.

For example, the transmission 18 is provided on the support member 12 and connected to the rotary shaft 14. The transmission 18 is provided between the electric motor 16 and the output rotary shaft 32. The transmission 18 transmits the rotational force of the output shaft 16A to the output rotary shaft 32. The transmission 18 changes the ratio of the rotational speed of the output rotary shaft 32 to the rotational speed of the output shaft 16A.

The transmission 18 reduces or increases the rotational speed of the output shaft 16A in one or more stages. In this embodiment, the transmission 18 is a speed reducer. The transmission 18 may also be a speed increaser. In this embodiment, the transmission 18 reduces the rotational speed of the output shaft 16A in two stages. The transmission 18 may also be configured with pulleys.

The transmission 18 includes at least one gear and at least one gear shaft. In this embodiment, the transmission 18 includes a first gear 18A, a second gear 18B, a third gear 18C, a fourth gear 18D, and a gear shaft 18E. The first gear 18A is provided on the output shaft 16A. The second gear 18B is provided on the gear shaft 18E. The second gear 18B rotates integrally with the gear shaft 18E. The third gear 18C is provided on a different portion of the gear shaft 18E from the second gear 18B. The third gear 18C rotates integrally with the gear shaft 18E. The fourth gear 18D is provided on the output rotation shaft 32, coaxially with the output rotation shaft 32.

The first gear 18A transmits the rotational force of the output shaft 16A to the second gear 18B. The number of teeth of the first gear 18A is fewer than the number of teeth of the second gear 18B. The rotational force of the output shaft 16A transmitted to the second gear 18B rotates the gear shaft 18E. The number of teeth of the second gear 18B is greater than the number of teeth of the third gear 18C. The third gear 18C transmits the rotational force of the gear shaft 18E to the fourth gear 18D. The number of teeth of the third gear 18C is fewer than the number of teeth of the fourth gear 18D. The rotational force of the gear shaft 18E transmitted to the fourth gear 18D rotates the output rotation shaft 32.

For example, the drive unit 10 includes a one-way clutch 36. The one-way clutch 36 is provided in the transmission 18. The one-way clutch 36 is configured to suppress transmission of the rotational force of the output rotary shaft 32 to the electric motor 16 when the output rotary shaft 32 rotates in the first rotational direction A1. When the output rotary shaft 32 rotates in the first rotational direction A1, the human-powered vehicle moves forward.

For example, the one-way clutch 36 includes a roller clutch. For example, the one-way clutch 36 is provided between the outer periphery of the output rotary shaft 32 and the inner periphery of the fourth gear 18D. The one-way clutch 36 includes an inner ring, an outer ring, and a plurality of rollers provided between the inner ring and the outer ring. For example, the inner ring is provided on the outer periphery of the output rotary shaft 32. For example, the inner ring is formed integrally with the outer periphery of the output rotary shaft 32. For example, the outer ring is provided on the inner periphery of the fourth gear 18D. For example, the outer ring is formed integrally with the inner periphery of the fourth gear 18D. The one-way clutch 36 may include a pawl clutch or a sprag clutch. The drive unit 10 does not have to include the one-way clutch 36.

The support member 12 has a second cylindrical portion 42 that is arranged substantially coaxially with the central rotation axis C1. The first hole 26A of the housing 24 is provided in the inner periphery of the second cylindrical portion 42. For example, the second cylindrical portion 42 is formed integrally with the first housing 26.

The first bearing 20 is provided on the support member 12 and rotatably supports the rotating shaft 14 about the rotational center axis C1 of the rotating shaft 14. The first bearing 20 is provided in the first housing 26. The first bearing 20 is provided in the first hole 26A. For example, the first bearing 20 is disposed inside the second cylindrical portion 42. The first bearing 20 is, for example, a roller bearing. For example, the first bearing 20 rotatably supports the crankshaft 30 about the rotational center axis C1. For example, the first bearing 20 directly supports the crankshaft 30 or the output rotating shaft 32. In this embodiment, the first bearing 20 directly supports the crankshaft 30. The first bearing 20 may also be configured to directly support the output rotating shaft 32. When the first bearing 20 is configured to directly support the output rotating shaft 32, the first bearing 20 and the first member 22 are provided in the second housing 28, and the second bearing 38 is provided in the first housing 26.

For example, the first bearing 20 includes an inner ring 20A, an outer ring 20B, and multiple rolling elements 20C. For example, the inner ring 20A is coupled to the rotating shaft 14. For example, the inner ring 20A is press-fitted onto the rotating shaft 14. In this embodiment, the inner ring 20A is press-fitted onto the outer periphery of the crankshaft 30. The inner ring 20A rotates integrally with the crankshaft 30. For example, the outer ring 20B contacts the support member 12 in the radial direction X2 of the rotating shaft 14. The outer ring 20B is clearance-fitted into the support member 12. The outer ring 20B has a first end face 20D in the first direction X1. The first end face 20D faces in the first direction X1 in a direction from the central portion 30C of the crankshaft 30 toward the first end 30A. For example, the multiple rolling elements 20C are disposed between the inner ring 20A and the outer ring 20B.

For example, the drive unit 10 further includes a second bearing 38. The second bearing 38 is provided on the support member 12 and rotatably supports the rotary shaft 14 about the central rotation axis C1. The second bearing 38 is spaced apart from the first bearing 20 in the first direction X1. For example, the first end face 20D of the outer ring 20B of the first bearing 20 faces the opposite side from the second bearing 38 in the first direction X1. The second bearing 38 is provided in the second housing 28. The second bearing 38 is provided in the second hole 28A. The second bearing 38 is, for example, a roller bearing. In this embodiment, the second bearing 38 rotatably supports the output rotary shaft 32 about the central rotation axis C1.

For example, the second bearing 38 includes an inner ring 38A, an outer ring 38B, and multiple rolling elements 38C. The outer ring 38B is clearance-fitted into the support member 12. The outer ring 38B has a second end face 38D in the first direction X1. The inner ring 38A is connected to the rotating shaft 14. The inner ring 38A is press-fitted into the rotating shaft 14. In this embodiment, the inner ring 38A is press-fitted onto the outer periphery of the output rotating shaft 32. The inner ring 38A rotates integrally with the output rotating shaft 32. The outer ring 38B contacts the support member 12 in the radial direction X2 of the rotating shaft 14. The second end face 38D faces in the first direction X1 in a direction from the center portion 30C toward the second end portion 30B of the crankshaft 30. The multiple rolling elements 38C are disposed between the inner ring 38A and the outer ring 38B.

The first member 22 is mounted on the support member 12 so as to be movable in a first direction X1 parallel to the central axis of rotation C1, and is configured to position the first bearing 20 relative to the support member 12 in the first direction X1. For example, the first member 22 has a first cylindrical portion 40 arranged substantially coaxially with the central axis of rotation C1. For example, the crankshaft 30 passes through the first member 22. The first bearing 20 is arranged inside the first cylindrical portion 40. The first member 22 is arranged so as to be in contact with the first bearing 20 in the first direction X1. The first member 22 is configured to restrict movement of the first bearing 20 relative to the first member 22 in the first direction X1. The first member 22 restricts movement of the first bearing 20 in the first direction X1 from the central portion 30C of the crankshaft 30 toward the first end portion 30A. The first member 22 restricts movement of the first bearing 20 so that the first bearing 20 cannot move toward the first end 30A of the crankshaft 30 in the first direction X1 beyond the first member 22.

For example, the first member 22 has an opposing surface 22A that faces the first end face 20D of the outer ring 20B in the first direction X1. For example, the first member 22 has a protruding portion 22B that protrudes from the inner circumferential surface of the first cylindrical portion 40 toward the inside of the first cylindrical portion 40 in the radial direction X2. The protruding portion 22B has an opposing surface 22A.

The protruding portion 22B protrudes inward in the radial direction X2 so that the opposing surface 22A is parallel to the radial direction X2. The protruding portion 22B includes a first portion 22C and a second portion 22D. The first portion 22C is continuous with an end of the first cylindrical portion 40. The first portion 22C extends inward in the radial direction X2. The first portion 22C includes the opposing surface 22A. The second portion 22D is continuous with an end of the first portion 22C on the inner side in the radial direction X2. The second portion 22D includes a portion extending in the first direction X1 and a portion extending parallel to the radial direction X2. The inner diameter of the portion of the second portion 22D extending in the first direction X1 is smaller than the inner diameter of the first cylindrical portion 40. The first member 22 may be configured not to include the second portion 22D. A seal member 23 is disposed on the inner circumferential surface of the second portion 22D. The seal member 23 is disposed between the first member 22 and the crankshaft 30. For example, the seal member 23 is formed of an elastic body. For example, the seal member 23 is made of synthetic rubber. The seal member 23 contacts the inner circumferential surface of the second portion 22D and the outer circumferential surface of the crankshaft 30.

The opposing surface 22A is arranged to contact the first end face 20D. The opposing surface 22A applies a force to the first end face 20D in the first direction X1 from the first end 30A toward the central portion 30C of the crankshaft 30. The opposing surface 22A is configured to contact at least a portion of the first end face 20D of the outer ring 20B. As long as the opposing surface 22A contacts the outer ring 20B, the dimension of the opposing surface 22A in the radial direction X2 may be smaller than the thickness of the outer ring 20B.

The opposing surface 22A is configured to restrict movement of the outer ring 20B. The opposing surface 22A restricts movement of the outer ring 20B in the first direction X1 from the center portion 30C of the crankshaft 30 toward the first end portion 30A. The opposing surface 22A restricts movement of the outer ring 20B in the first direction X1 so that the outer ring 20B cannot move toward the first end portion 30A of the crankshaft 30 beyond the opposing surface 22A.

In this embodiment, the second cylindrical portion 42 is disposed inside the first cylindrical portion 40. For example, a first thread 40A is formed in the first cylindrical portion 40. In this embodiment, the first thread 40A is formed on the inner periphery of the first cylindrical portion 40. For example, the first thread 40A is formed on the inner periphery of the first cylindrical portion 40 over the entire length in the first direction X1. For example, a second thread 42A that is coupled to the first thread 40A is formed in the second cylindrical portion 42. In this embodiment, the second thread 42A is formed on the outer periphery of the second cylindrical portion 42. For example, the second thread 42A is formed on the outer periphery of the second cylindrical portion 42 over the entire length in the first direction X1.

For example, one of the first screw 40A and the second screw 42A is a male screw. The other of the first screw 40A and the second screw 42A is a female screw. In this embodiment, the first screw 40A is a female screw and the second screw 42A is a male screw.

For example, the first member 22 is provided on the housing 24 so as to be operable from outside the housing 24. The first member 22 is formed in an annular shape. The first member 22 is provided on the housing 24 so as to be operable from outside the housing 24 so as to rotate in the circumferential direction X3 of the first member 22. The first member 22 is provided on the housing 24 so as to be movable in the first direction X1 by an operator operating the first member 22 from outside the housing 24. The outside of the housing 24 is, for example, the outside of the storage space 24A.

For example, the first member 22 includes a first tool engagement portion 22E that can engage with a tool. The first tool engagement portion 22E includes a flat portion. For example, the outer periphery of the first tubular portion 40 is formed in a polygonal shape. The tool that engages with the first tool engagement portion 22E is, for example, a wrench. The first member 22 is operated with the tool so that the second screw 42A is screwed into the first screw 40A. The first member 22 is rotated in the circumferential direction X3 by the tool. The first member 22 moves in the first direction X1 by being rotated in the circumferential direction X3 by the tool. The first tool engagement portion 22E may be provided on the outer periphery of the second portion 22D.

For example, the drive unit 10 further includes a second member 44. The second member 44 restricts movement of the first member 22 relative to the support member 12 in the first direction X1. The second member 44 is positioned closer to the second end 30B than the first member 22 in the first direction X1. The second member 44 restricts movement of the first member 22 in the direction from the first end 30A toward the central portion 30C of the crankshaft 30 in the first direction X1. The second member 44 restricts movement of the first member 22 so that the first member 22 cannot move closer to the first end 30A of the crankshaft 30 in the first direction X1 than the second member 44. The second member 44 is formed in an annular shape.

The second member 44 has a contact surface 44A that faces the first member 22. The contact surface 44A is arranged to contact the end 22F of the first member 22. The contact surface 44A applies pressure to the end 22F in the first direction X1, from the center 30C of the crankshaft 30 toward the first end 30A.

For example, the second member 44 has a third cylindrical portion 46. The third cylindrical portion 46 is formed with a third thread 46A that is coupled to the second thread 42A. The third thread 46A is formed on the inner periphery of the third cylindrical portion 46. For example, the third thread 46A is formed on the inner periphery of the third cylindrical portion 46 over the entire section in the first direction X1. The third cylindrical portion 46 is arranged substantially coaxially with the first cylindrical portion 40. The third cylindrical portion 46 is arranged substantially coaxially with the second cylindrical portion 42. In this embodiment, for example, the first thread 40A is a female thread. The second thread 42A is a male thread. The third thread 46A is a female thread.

For example, the second member 44 is provided on the housing 24 so as to be operable from outside the housing 24. The second member 44 is provided on the housing 24 so as to be operable from outside the housing 24 to rotate in the circumferential direction X3. The second member 44 is provided on the housing 24 so as to be operable from outside the housing 24 to move in the first direction X1. For example, the second member 44 is provided on the housing 24 so as to be operable with a tool from outside the housing 24. For example, the second member 44 is a lock nut.

For example, the second member 44 includes a second tool engagement portion 44B that can engage with a tool. For example, the second tool engagement portion 44B includes a flat portion. For example, the outer periphery of the second tool engagement portion 44B is formed in a polygonal shape. A tool that engages with the second tool engagement portion 44B is, for example, a wrench. The second member 44 is operated by the tool so that the second screw 42A is screwed into the third screw 46A. The second member 44 is rotated in the circumferential direction X3 by the tool. When the second member 44 is rotated in the circumferential direction X3 by the tool, it moves in the first direction X1.

The method for attaching the rotating shaft 14 to the drive unit 10 includes steps 1, 2, 3, and 4.

The first step includes placing the rotating shaft 14, first bearing 20, and second bearing 38 in the housing 24. Before the first step, the inner ring 20A of the first bearing 20 is press-fitted onto the rotating shaft 14. Before the first step, the inner ring 38A of the second bearing 38 is press-fitted onto the rotating shaft 14. With the first bearing 20 and second bearing 38 attached to the rotating shaft 14, the rotating shaft 14 is placed in the accommodation space 24A of the housing 24.

The second step includes attaching the second member 44 to the support member 12. The second screw 42A is threaded into the third screw 46A, thereby attaching the second member 44 to the support member 12.

The third step includes attaching the first member 22 to the support member 12. The second screw 42A is threaded into the first screw 40A, thereby attaching the first member 22 to the support member 12. In the third step, the first member 22 moves relative to the support member 12 in the first direction X1 so that the opposing surface 22A contacts the first end face 20D. In the third step, the first member 22 moves relative to the support member 12 in the first direction X1, from the first end 30A of the crankshaft 30 toward the central portion 30C.

In the third step, the opposing surface 22A contacts the first end face 20D, causing the first member 22 to move relative to the support member 12 until the first bearing 20 stops moving in the first direction X1. In the third step, the second bearing 38 moves integrally with the rotating shaft 14 in the first direction X1, from the first end 30A toward the central portion 30C of the crankshaft 30. When the second bearing 38 contacts the side wall portion of the second housing 28, the first bearing 20 stops moving in the first direction X1, from the first end 30A toward the central portion 30C of the crankshaft 30.

The fourth step includes restricting the movement of the first member 22 by the second member 44. The second member 44 moves relative to the support member 12 until the contact surface 44A contacts the end portion 22F.

When a human-powered vehicle includes an external derailleur, gear shifting by the external derailleur can cause the crankshaft 30 to rattle relative to the support member 12. An example of an external derailleur is a front derailleur. The first member 22 restricts movement of the first bearing 20 in the first direction X1, making the crankshaft 30 less likely to rattle. The drive unit 10 reduces the rider's discomfort caused by gear shifting by the external derailleur, allowing the rider to use the human-powered vehicle comfortably.

Because the first member 22 of the drive unit 10 can be operated externally, the position of the first bearing 20 relative to the support member 12 can be adjusted after the rotating shaft 14 is placed in the housing 24. This makes it easier to control the accuracy of the drive unit 10, improving productivity of the drive unit 10.

Second Embodiment
A drive unit 10 of the second embodiment will be described with reference to Figure 5. The drive unit 10 of the second embodiment has the same configuration as the first embodiment, except that the configuration of the first member 48, the configuration of the second cylindrical portion 50, and the configuration of the second member 52 are different from those of the drive unit 10 of the first embodiment. Therefore, the same reference numerals as in the first embodiment are used for the configurations common to the first embodiment, and redundant description will be omitted.

In this embodiment, the first member 48 has a first cylindrical portion 54 that is arranged substantially coaxially with the central rotation axis C1. A first thread 54A is formed on the first cylindrical portion 54. The first thread 54A is formed on the outer periphery of the first cylindrical portion 54. The first thread 54A is formed on the outer periphery of the first cylindrical portion 54 over the entire section in the first direction X1. The first member 48 is formed in an annular shape.

The first member 48 has an end portion 48B in the first direction X1. The end portion 48B has an opposing surface 48A. The opposing surface 48A has a configuration similar to the opposing surface 22A in the first embodiment. The first member 48 has a protrusion 48C at the end portion 48B that protrudes from the inner surface of the first cylindrical portion 54 toward the inside of the first cylindrical portion 54 in the radial direction X2. The protrusion 48C is configured so that its thickness from the outer surface of the first cylindrical portion 54 is the same as the thickness of the first member 48 in the radial direction X2. In this embodiment, the first member 48 is configured so that its thickness in the radial direction X2 is uniform. In the first member 48, the thickness of the end portion 48B may be greater than the thickness of the portion excluding the end portion 48B. If the thickness of the end portion 48B is greater than the thickness of the portion excluding the end portion 48B, the end portion 48B protrudes inward in the radial direction X2 so that the opposing surface 48A is parallel to the radial direction X2. The end 48B that protrudes inward in the radial direction X2 constitutes the protruding portion 48C.

For example, the support member 12 has a second cylindrical portion 50 that is arranged substantially coaxially with the central rotation axis C1. The support member 12 of the second embodiment is configured similarly to the support member 12 of the first embodiment, except that the second cylindrical portion 42 is replaced with the second cylindrical portion 50. The second cylindrical portion 50 is formed with a second thread 50A that is coupled to the first thread 54A. The second cylindrical portion 50 is arranged substantially coaxially with the first cylindrical portion 54. The second thread 50A is formed on the inner periphery of the second cylindrical portion 50. The second thread 50A is formed on the inner periphery of the second cylindrical portion 50 over a portion of the first direction X1.

The second cylindrical portion 50 is configured so that the inner periphery of the second cylindrical portion 50 contacts the outer periphery of the outer ring 20B. A first hole 26A is formed in the inner periphery of the second cylindrical portion 50. In this embodiment, the first cylindrical portion 54 is disposed on the inner periphery of the second cylindrical portion 50. When the first cylindrical portion 54 is disposed on the inner periphery of the second cylindrical portion 50, the first thread 54A is a male thread and the second thread 50A is a female thread.

For example, the first member 48 is provided on the housing 24 so as to be operable from outside the housing 24. The first member 48 is provided on the housing 24 so as to be operable to rotate in the circumferential direction X3 from outside the housing 24. The first member 48 is provided on the housing 24 so as to be operable to move in the first direction X1 from outside the housing 24. The outside of the housing 24 includes, for example, the outside of the storage space 24A.

For example, the first member 48 includes a first tool engagement portion 48E that can engage with a tool. For example, the first tool engagement portion 48E is provided on the inner periphery of the first member 48. The shape of the first tool engagement portion 48E is not particularly limited. For example, the first tool engagement portion 48E may be formed by a plurality of splines extending in the first direction X1 and spaced apart in the first rotational direction A1. For example, at least a portion of the inner periphery of the first member 48 may be formed in a hexagonal shape when viewed from the first direction X1. The first member 48 is operated by a tool so that the first thread 54A is threaded into the second thread 50A. The first member 48 is rotated in the circumferential direction X3 by the tool. The first member 48 moves in the first direction X1 by being rotated in the circumferential direction X3 by the tool.

A flange 49 that protrudes inward in the radial direction X2 may be formed on the inner periphery of the first member 48. The flange 49 is positioned so as not to come into contact with the crankshaft 30 and is formed so as to cover the first bearing 20.

In this embodiment, the drive unit 10 further includes a second member 52. The second member 52 restricts movement of the first member 48 relative to the support member 12 in the first direction X1. The second member 52 is positioned closer to the first end 30A than the first member 48 in the first direction X1. The second member 52 restricts movement of the first member 48 in the direction from the center portion 30C of the crankshaft 30 toward the first end 30A in the first direction X1. The second member 52 restricts movement of the first member 48 so that the first member 48 cannot move closer to the first end 30A of the crankshaft 30 in the first direction X1 than the second member 52. The second member 52 is formed in an annular shape.

For example, the second member 52 has a contact surface 52A that contacts the support member 12. The contact surface 52A is provided on the second member 52 so as to contact the second cylindrical portion 50. The contact surface 52A applies pressure to the second cylindrical portion 50 in the first direction X1, in a direction from the first end portion 30A toward the central portion 30C of the crankshaft 30.

The second member 52 has a third cylindrical portion 58. A third thread 58A that is coupled to the first thread 54A is formed in the third cylindrical portion 58. The third thread 58A is formed on the inner periphery of the third cylindrical portion 58. For example, the third thread 58A is formed on the inner periphery of the third cylindrical portion 58 over the entire section in the first direction X1. The third cylindrical portion 58 is disposed substantially coaxially with the first cylindrical portion 54. The third cylindrical portion 58 is disposed substantially coaxially with the second cylindrical portion 50. In the present embodiment, for example, the first thread 54A is a male thread. The second thread 50A is a female thread. The third thread 58A is a female thread.

For example, the second member 52 is provided on the housing 24 so as to be operable from outside the housing 24. The second member 52 is provided on the housing 24 so as to be operable to rotate in the circumferential direction X3 from outside the housing 24. The second member 52 is provided on the housing 24 so as to be operable to move in the first direction X1 from outside the housing 24.

For example, the second member 52 includes a second tool engagement portion 52B that can engage with a tool. The second tool engagement portion 52B is provided on the outer periphery of the second member 52. The second tool engagement portion 52B includes a flat portion. For example, the outer periphery of the second member 52 is formed in a polygonal shape. A tool that engages with the second tool engagement portion 52B is, for example, a wrench. The second member 52 is operated by the tool so that the third screw 58A is screwed into the second screw 50A. The second member 52 is rotated in the circumferential direction X3 by the tool. The second member 52 moves in the first direction X1 when rotated in the circumferential direction X3 by the tool.

<Modification>
The descriptions of each embodiment are intended to exemplify possible forms of a drive unit for a human-powered vehicle according to the present disclosure and are not intended to limit the forms. A drive unit for a human-powered vehicle according to the present disclosure can take the form of, for example, a modified version of each of the embodiments shown below, or a combination of at least two mutually consistent modified versions. In the following modified versions, parts that are common to the embodiments are given the same reference numerals as in the embodiments, and their description will be omitted.

- The first member 22 may be arranged so as to contact the second bearing 38. When the first member 22 is arranged so as to contact the second bearing 38, the first member 22 is arranged around the output rotation shaft 32. The opposing surface 22A of the first member 22 faces the second end face 38D of the outer ring 38B. The opposing surface 22A is configured to restrict movement of the outer ring 38B. The opposing surface 22A restricts movement of the outer ring 38B in the direction from the center portion 30C of the crankshaft 30 toward the second end 30B in the first direction X1. The opposing surface 22A restricts movement of the outer ring 38B so that the outer ring 38B cannot move toward the second end 30B of the crankshaft 30 in the first direction X1 beyond the opposing surface 22A.

In the first embodiment, the inner peripheral portion of the first cylindrical portion 40 may contact the outer peripheral portion of the outer ring 20B. When the inner peripheral portion of the first cylindrical portion 40 contacts the outer peripheral portion of the outer ring 20B, the second cylindrical portion 42 does not contact the outer peripheral portion of the outer ring 20B. The first thread 40A is formed on the outer peripheral portion of the first cylindrical portion 40. The second thread 42A is formed on the inner peripheral portion of the second cylindrical portion 42. The third thread 46A is formed on the outer peripheral portion of the third cylindrical portion 46.

- The opposing surfaces 22A, 48A may be configured to contact the inner ring 20A. If the opposing surfaces 22A, 48A are configured to contact the inner ring 20A, for example, the dimension of the opposing surfaces 22A, 48A in the radial direction X2 can be increased, allowing the first member 22 to better restrict movement of the first bearing 20 in the first direction X1.

- An elastic member may be provided between the opposing surfaces 22A, 48A and the outer ring 20B. When an elastic member is provided between the opposing surfaces 22A, 48A and the outer ring 20B, the elastic member biases the outer ring 20B in the first direction X1 from the first end 30A toward the center 30C of the crankshaft 30. The elastic member is, for example, a wave washer. Because the elastic member biases the first bearing 20, rattle of the crankshaft 30 relative to the support member 12 is reduced.

- A resin member may be provided on the opposing surfaces 22A, 48A. When a resin member is provided on the opposing surfaces 22A, 48A, the resin member comes into contact with the outer ring 20B. The elastic member may be, for example, rubber. The elastic member reduces noise generated by contact between the first member 22 and the bearing.

- The drive unit 10 may be configured as a hub motor mounted on the wheel of a human-powered vehicle. When the drive unit 10 is configured as a hub motor mounted on the wheel of a human-powered vehicle, the rotating shaft 14 does not include the crankshaft 30. When the drive unit 10 is configured as a hub motor mounted on the wheel of a human-powered vehicle, the rotating shaft 14 includes, for example, a hub shell.

As used herein, the phrase "at least one" means "one or more" of the desired options. As an example, when the number of options is two, the phrase "at least one" means "only one option" or "both of two options." As another example, when the number of options is three or more, the phrase "at least one" means "only one option" or "any combination of two or more options."

10...drive unit, 12...support member, 12A...mounting portion, 14...rotating shaft, 16...electric motor, 18...transmission device, 20...first bearing, 20A...inner ring, 20B...outer ring, 20C...rolling element, 20D...first end surface, 22, 48...first member, 22A, 48A...opposing surface, 22B, 48C...protrusion, 22E, 48E...first tool engagement portion, 24 ...housing, 24A...accommodation space, 30...crankshaft, 32...output rotating shaft, 38...second bearing, 40, 54...first cylindrical portion, 40A, 54A...first screw, 42, 50...second cylindrical portion, 42A, 50A...second screw, 44, 52...second member, 44B, 52B...second tool engagement portion, 46, 58...third cylindrical portion, 46A, 58A...third screw.

Claims (13)

A drive unit for a human-powered vehicle,
a support member formed separately from the frame of the human-powered vehicle;
a rotation shaft passing through the support member;
At least one of an electric motor provided on the support member and configured to provide a propulsive force to the human-powered vehicle, and a transmission provided on the support member and connected to the rotary shaft;
a first bearing provided in the support member and configured to rotatably support the rotating shaft about a rotational axis of the rotating shaft;
a first member provided on the support member so as to be movable in a first direction parallel to the rotation central axis, and configured to position the first bearing relative to the support member in the first direction;
a second member that restricts movement of the first member relative to the support member in the first direction,
the rotating shaft includes at least one of a crankshaft and an output rotating shaft that is disposed radially outward of the crankshaft and coaxial with the crankshaft, and to which a rotational force input to the crankshaft is transmitted,
the first bearing directly supports the crankshaft or the output rotating shaft,
the first member includes an end portion provided on a central side of the rotation shaft in the first direction,
The second member is provided closer to the center of the rotation shaft than the first member in the first direction. the first member has a first cylindrical portion disposed substantially coaxially with the rotation central axis,
a first thread is formed on the first cylindrical portion;
the support member has a second cylindrical portion disposed substantially coaxially with the rotation central axis,
a second thread coupled to the first thread is formed on the second cylindrical portion;
one of the first screw and the second screw is a male screw;
The drive unit according to claim 1 , wherein the other of the first screw and the second screw is a female screw. the second member has a third cylindrical portion,
a third screw thread coupled to the second screw thread is formed on the third cylindrical portion;
the first thread is a female thread,
the second screw is a male screw,
The drive unit according to claim 2 , wherein the third screw is an internal screw. A drive unit for a human-powered vehicle,
a support member formed separately from the frame of the human-powered vehicle;
a rotation shaft passing through the support member;
At least one of an electric motor provided on the support member and configured to provide a propulsive force to the human-powered vehicle, and a transmission provided on the support member and connected to the rotary shaft;
a first bearing provided in the support member and configured to rotatably support the rotating shaft about a rotational axis of the rotating shaft;
a first member that is provided on the support member so as to be movable in a first direction parallel to the rotation central axis and that is configured to position the first bearing relative to the support member in the first direction,
the first member has a first cylindrical portion disposed substantially coaxially with the rotation central axis,
a first thread is formed on the first cylindrical portion;
the support member has a second cylindrical portion disposed substantially coaxially with the rotation central axis,
a second thread coupled to the first thread is formed on the second cylindrical portion;
one of the first screw and the second screw is a male screw;
the other of the first screw and the second screw is a female screw,
a second member that restricts movement of the first member relative to the support member in the first direction,
the second member has a third cylindrical portion,
a third screw thread coupled to the second screw thread is formed on the third cylindrical portion;
the first thread is a female thread,
the second screw is a male screw,
The drive unit, wherein the third screw is a female screw. A drive unit for a human-powered vehicle,
a support member formed separately from the frame of the human-powered vehicle;
a rotation shaft passing through the support member;
At least one of an electric motor provided on the support member and configured to provide a propulsive force to the human-powered vehicle, and a transmission provided on the support member and connected to the rotary shaft;
a first bearing provided in the support member and configured to rotatably support the rotating shaft about a rotational axis of the rotating shaft;
a first member provided on the support member so as to be movable in a first direction parallel to the rotation central axis, and configured to position the first bearing relative to the support member in the first direction;
a second member that restricts movement of the first member relative to the support member in the first direction,
the rotating shaft includes at least one of a crankshaft and an output rotating shaft that is disposed radially outward of the crankshaft and coaxial with the crankshaft, and to which a rotational force input to the crankshaft is transmitted,
the first bearing directly supports the crankshaft or the output rotating shaft,
the support member includes a second cylindrical portion through which the rotation shaft passes,
the first member includes a first cylindrical portion provided on an inner peripheral side of the second cylindrical portion,
the second member includes a contact surface that contacts the support member, and a third cylindrical portion that is provided on an outer circumferential side of the first cylindrical portion,
The first bearing is
an inner ring connected to the rotating shaft;
an outer ring that contacts the support member in a radial direction of the rotating shaft;
a plurality of rolling elements disposed between the inner ring and the outer ring,
The first member is
an opposing surface opposing a first end surface of the outer ring in the first direction;
a protrusion protruding from an inner circumferential surface of the first cylindrical portion toward a radially inner side of the first cylindrical portion,
The protrusion has the opposing surface . the first cylindrical portion is disposed substantially coaxially with the rotation central axis,
a first thread is formed on the first cylindrical portion;
the second cylindrical portion is disposed substantially coaxially with the rotation central axis,
a second thread coupled to the first thread is formed on the second cylindrical portion;
one of the first screw and the second screw is a male screw;
The drive unit according to claim 5 , wherein the other of the first screw and the second screw is a female screw. a third screw thread coupled to the first screw thread is formed on the third cylindrical portion;
the first thread is a male thread,
the second thread is a female thread,
The drive unit according to claim 6 , wherein the third thread is an internal thread. The drive unit according to claim 5 , wherein the inner ring is press-fitted onto the rotary shaft. a second bearing provided on the support member and configured to rotatably support the rotation shaft with respect to the rotation central axis;
the second bearing is spaced apart from the first bearing in the first direction;
The drive unit according to claim 5 , wherein the first end surface of the outer ring of the first bearing faces away from the second bearing in the first direction. The support member includes a housing that defines an accommodation space,
The drive unit according to claim 1 , wherein the first member is provided on the housing so as to be operable from outside the housing. The drive unit according to claim 1 , wherein the second member includes a second tool engagement portion that is capable of engaging a tool. The drive unit according to claim 1 , wherein the first member includes a first tool engagement portion that is capable of engaging a tool. The drive unit according to claim 1 , wherein the support member has a mounting portion that is attached to the frame of the human-powered vehicle.