JP7292956B2 - Drive unit for human powered vehicle - Google Patents

Description

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

For example, in a drive unit for a human-powered vehicle disclosed in Patent Document 1, an electric circuit board is accommodated in a housing.

JP 2018-158695 A

SUMMARY OF THE INVENTION One of the objects of the present invention is to provide a drive unit for a human-powered vehicle capable of suppressing an increase in heat of an electric circuit board.

A drive unit according to a first aspect of the present disclosure is a drive unit for a manpowered vehicle, comprising: a housing having a housing space; and a motor provided in the housing and configured to impart propulsion to the manpowered vehicle. , a first substrate surface, a second substrate surface opposite to the first substrate surface, and a control circuit for controlling the motor, and arranged in the accommodation space; a fixing portion fixed in the housing space; and a heat conducting portion, unlike the fixing portion, conducting heat from the electric circuit board to the housing by contacting the electric circuit board and the housing. wherein the heat-conducting part comprises: a first heat-conducting part provided between the first substrate surface and the housing; a second heat-conducting part provided between the second substrate surface and the housing; including.
According to the drive unit on the first side, the first heat conducting portion allows heat to be dissipated from the first board surface of the electric circuit board to the housing, and the second heat conducting portion allows heat to be dissipated from the second board surface of the electric circuit board to the housing. It is possible to suitably suppress an increase in the heat of the electric circuit board.

A drive unit according to a second aspect of the present disclosure is a drive unit for a manpowered vehicle, and includes a housing having an accommodation space, a motor provided in the housing , a control circuit for controlling the motor, the accommodation space a fixing portion for fixing the electric circuit board in the housing space; and, unlike the fixing portion, the electric circuit board can a heat conducting portion for conducting heat of the motor to the housing, the heat conducting portion including a first heat conducting portion provided between the electric circuit board and the motor.
According to the drive unit on the second side, the heat can be dissipated to the housing arranged between the circuit board and the motor by the first heat conducting portion, so that the heat rise of the electric circuit board can be suitably suppressed.

In the drive unit of the third aspect according to the second aspect of the present disclosure, the electric circuit board has a first substrate surface and a second substrate surface opposite to the first substrate surface, and the first heat conducting part comprises: , provided between the first substrate surface and the housing, wherein the thermally conductive portion further includes a second thermally conductive portion provided between the second substrate surface and the housing.
According to the drive unit of the third side, the first heat conducting part can dissipate heat from the first substrate surface of the electric circuit board to the housing, and the second heat conducting part can dissipate heat from the second substrate surface of the electric circuit board to the housing. It is possible to suitably suppress an increase in the heat of the electric circuit board.

In the drive unit of the fourth aspect according to the first or third aspect of the present disclosure, the housing includes a first housing and a second housing, the first heat conducting portion contacts the first housing, the second A heat-conducting portion contacts the second housing.
According to the drive unit of the fourth side, the heat of the electric circuit board can be radiated to the first housing by the first heat conducting portion, and can be radiated to the second housing by the second heat conducting portion.

In the drive unit of the fifth aspect according to any one of the first to fourth aspects of the present disclosure, the motor includes a rotor and a stator, and between the rotor and the stator and the electric circuit board, the housing is provided.
According to the drive unit of the fifth aspect, the heat conducting portion can be brought into contact with the portion of the housing that is arranged between the rotor and stator and the electric circuit board.

In the drive unit of the sixth aspect according to any one of the first, third, and fourth aspects of the present disclosure, the motor includes a rotor and a stator, and the rotor and stator and the electric circuit board are connected to each other. A portion of the housing is provided therebetween, and at least a portion of the second heat conducting portion overlaps at least one of the rotor and the stator when viewed in the axial direction of the rotor.
According to the drive unit of the sixth aspect, at least part of the second heat conducting part can be arranged so as to overlap at least part of the rotor and stator when viewed from the axial direction of the rotor.

In the drive unit of the seventh aspect according to the fifth or sixth aspect of the present disclosure, a space is formed between a portion of the housing with which the first heat conducting portion contacts and the rotor and the stator.
According to the drive unit of the seventh side, the heat of the rotor and the stator is brought into contact with the first heat conducting portion of the housing by the space formed between the portion in contact with the first heat conducting portion and the rotor and the stator. Therefore, the heat of the rotor and stator is less likely to be transmitted to the electric circuit board via the first heat conducting portion.

In the drive unit of the eighth aspect according to any one of the fifth to seventh aspects of the present disclosure, at least a part of the first heat conducting part is at least part of the rotor and the stator when viewed from the axial direction of the rotor. overlap with some
According to the drive unit of the eighth aspect, at least part of the first heat conducting section can be arranged so as to overlap at least one of the rotor and the stator when viewed from the axial direction of the rotor.

In the drive unit of the ninth aspect according to any one of the fifth to eighth aspects of the present disclosure, the housing includes a case that accommodates the stator and the rotor.
According to the drive unit of the ninth aspect, the heat of the electric circuit board can be dissipated to the housing including the case that accommodates the stator and rotor by the heat conducting portion.

In the tenth aspect drive unit according to any one of the first to ninth aspects of the present disclosure, the motor includes an output shaft, and the housing includes a through hole through which the output shaft passes.
According to the drive unit of the tenth aspect, the heat of the electric circuit board can be dissipated by the heat conducting portion to the housing including the through hole through which the output shaft passes.

In the drive unit according to the eleventh aspect according to any one of the first to tenth aspects of the present disclosure, the control circuit includes a plurality of electronic elements, and the heat conducting section controls the amount of heat generated from among the plurality of electronic elements. contact the electronic element with the largest .
According to the drive unit of the eleventh aspect, the heat from the portion of the electric circuit board that tends to get very hot can be dissipated to the housing.

The drive unit of the twelfth aspect according to any one of the first through tenth aspects of the present disclosure, further comprising a crankshaft provided in the housing.
According to the drive unit of the twelfth aspect, it is possible to suitably suppress the heat rise of the electric circuit board in the drive unit including the crankshaft.

In the drive unit of the thirteenth aspect according to any one of the first to tenth aspects of the present disclosure, the heat conducting section includes at least one of an elastic body and a viscous fluid.
According to the drive unit of the thirteenth side, it is easy to dispose the heat-conducting portion between the electric circuit board and the housing, and the heat-conducting portion can preferably contact the housing.

In the fourteenth aspect of the drive unit according to the thirteenth aspect of the present disclosure, the elastic body includes a heat transfer sheet.
According to the drive unit of the fourteenth aspect, the heat transfer sheet can preferably dissipate the heat of the electric circuit board to the housing.

In the drive unit of the fifteenth aspect according to the thirteenth or fourteenth aspect of the present disclosure, the viscous fluid includes grease.
According to the drive unit of the fifteenth aspect, the heat of the electric circuit board can be preferably dissipated to the housing by the grease.

In the drive unit of the sixteenth aspect according to any one of the thirteenth to fifteenth aspects of the present disclosure, the heat conducting portion comprises silicone.
According to the drive unit of the sixteenth aspect, the heat of the electric circuit board can be preferably radiated to the housing by silicone.

A drive unit for a manpowered vehicle according to the present disclosure can suppress an increase in heat in an electric circuit board.

Sectional drawing of the drive unit for manpower-driven vehicles of embodiment. FIG. 2 is a front view of the drive unit of FIG. 1 with a first housing removed; Sectional drawing of the drive unit for manpower-driven vehicles of a modification.

(embodiment)
A drive unit 10 for a manpowered vehicle according to an embodiment will be described with reference to FIGS. 1 and 2. FIG. A man-powered vehicle is a vehicle that can be driven by at least man-powered propulsion. Manpowered vehicles are not limited in the number of wheels and include, for example, one-wheeled vehicles and vehicles with three or more wheels. Human-powered vehicles include various types of bicycles, such as mountain bikes, road bikes, city bikes, cargo bikes, and recumbents, as well as electric bicycles (E-bikes). Electric bicycles include power-assisted bicycles that assist the propulsion of the vehicle with an electric motor. Hereinafter, in the embodiments, the human-powered vehicle will be described as a bicycle.

The drive unit 10 includes a housing 12 having an accommodation space S, a motor 14 , an electric circuit board 16 , a fixed portion 18 and a heat conducting portion 20 . A motor 14 is provided in the housing 12 and is configured to provide propulsion to the manpowered vehicle. The electric circuit board 16 has a first board surface 22 , a second board surface 24 opposite to the first board surface 22 , and a control circuit 26 for controlling the motor 14 , and is arranged in the accommodation space S. The fixing portion 18 fixes the electric circuit board 16 in the housing space S. As shown in FIG. Unlike the fixed part 18 , the heat conducting part 20 conducts the heat of the electric circuit board 16 to the housing 12 by contacting the electric circuit board 16 and the housing 12 . The heat conducting portion 20 includes a first heat conducting portion 28 provided between the first substrate surface 22 and the housing 12, a second heat conducting portion 30 provided between the second substrate surface 24 and the housing 12, including.

Housing 12 preferably includes a first housing 32 and a second housing 34 . The first housing 32 contains, for example, at least one of an aluminum alloy and a magnesium alloy. The second housing 34 contains, for example, at least one of an aluminum alloy and a magnesium alloy. The first housing 32 and the second housing 34 are arranged next to each other, for example, in a direction parallel to the rotation center axis C1 of the motor 14 . The first housing 32 and the second housing 34 are attached to each other by bolts or the like, for example. The outer periphery of the housing 12 is preferably provided with a mounting portion 12A for mounting to the frame of a manpowered vehicle. The mounting portion 12</b>A includes a convex portion that protrudes from the outer peripheral portion of the housing 12 . The mounting portion 12A includes, for example, through holes. The housing 12 is attached to the frame of the manpowered vehicle by the bolt passing through the through hole of the mounting portion 12A and being coupled to the female threaded portion provided on the frame of the manpowered vehicle. A female thread may be formed on the inner peripheral surface of the through-hole of the mounting portion 12A, and a nut member may be press-fitted into the through-hole of the mounting portion 12A. In this case, the housing 12 may be attached to the frame of the manpowered vehicle by passing the bolt through a through hole provided in the frame of the manpowered vehicle and coupling it to the female thread of the mounting portion 12A or the female thread of the nut member. good.

Drive unit 10 preferably further includes a crankshaft 36 provided in housing 12 . The rotation center axis C2 of the crankshaft 36 is preferably parallel to the rotation center axis C1 of the motor 14 . Drive unit 10 preferably further includes an output 38 . Output portion 38 includes a hollow shaft. The hollow shaft of the output portion 38 has the crankshaft 36 inserted therein and surrounds a portion of the crankshaft 36 . A first end 38 A of the output portion 38 is located inside the housing 12 . A second end 38B of the output portion 38 is exposed from the housing 12 . The first housing 32 is provided with a first hole 32A through which the first end portion 36A of the crankshaft 36 passes in a direction parallel to the rotation center axis C2 of the crankshaft 36 . A first end 36A of the crankshaft 36 is supported by the first housing 32 via a first bearing 40 . The second housing 34 is provided with a second hole 34A through which the second end 36B of the crankshaft 36 and the second end 38B of the output portion 38 pass in a direction parallel to the rotation center axis C2 of the crankshaft 36. be done. The output portion 38 is supported by the second housing 34 via a second bearing 42 . A crank arm is attached to a portion of the crankshaft 36 exposed to the outside of the housing 12 through the first hole 32A and a portion exposed to the outside of the housing 12 through the second hole 34A. A rotating body coupled to a transmission member coupled to a drive wheel of a manpowered vehicle is attached to a portion of the second end portion 38B of the output portion 38 that is exposed to the outside of the housing 12 through the second hole 34A. A mounting portion 46 is provided. Rotating bodies include, for example, sprockets, pulleys, or bevel gears. Transmission members include, for example, chains, belts, or shafts. The first bearing 40 and the second bearing 42 include radial ball bearings, for example.

The crankshaft 36 is supported by the first housing 32 via a first bearing 40 and supported by the output portion 38 via a sleeve 44 . The output portion 38 is connected to the crankshaft 36 . A first end portion 38A of the output portion 38 is connected to the crankshaft 36 in a direction parallel to the rotation center axis C2 of the crankshaft 36 . The output portion 38 and the crankshaft 36 may be directly connected, or may be connected via another member. The output portion 38 and the crankshaft 36 may be connected via a first one-way clutch.

The motor 14 is configured to provide propulsion to the manpowered vehicle. Motor 14 includes an electric motor. In this embodiment, motor 14 is configured to transmit rotation to output 38 . The power transmission path between the motor 14 and the output portion 38 is preferably configured so that the rotational force of the crankshaft 36 does not cause the motor 14 to rotate when the crankshaft 36 is rotated in the forward direction of the manpowered vehicle. A second one-way clutch 48 is provided. Between the output shaft 50 of the motor 14 and the output portion 38, preferably, a speed reducer 52 is provided to reduce the speed of rotation of the motor 14 and output it. The second one-way clutch 48 may be provided on the speed reducer 52 .

The speed reducer 52 is configured, for example, to reduce the speed of rotation of the motor 14 in a plurality of steps and transmit the speed to the output section 38 . Reduction gear 52 includes at least one of a gear and a pulley. The speed reducer 52 of FIG. 1 includes a first gear 54 , a second gear 56 , a third gear 58 and a fourth gear 60 . A first gear 54 is provided on the output shaft 50 of the motor 14 . The second gear 56 is provided on a first transmission shaft 62 provided at a portion different from the output shaft 50 and meshes with the first gear 54 . The third gear 58 is provided on a portion of the first transmission shaft 62 different from the second gear 56 . A fourth gear 60 is provided on the outer peripheral portion of the output portion 38 and meshes with the third gear 58 . The number of teeth of the second gear 56 is greater than the number of teeth of the first gear 54 . The number of teeth of the fourth gear 60 is greater than the number of teeth of the third gear 58 . In this embodiment, the speed reducer 52 is configured to reduce the speed of the rotation of the motor 14 in two stages and transmit the speed to the output section 38 . The speed reducer 52 may be configured to reduce the rotation of the motor 14 by one step and transmit it to the output section 38 .

The motor 14 includes an output shaft 50, and the housing 12 includes a through hole 12B through which the output shaft 50 passes. Motor 14 includes rotor 14A and stator 14B. Motor 14 is preferably an inner rotor type motor. When the motor 14 is an inner rotor type motor, the stator 14B is provided on the inner circumference of the housing 12 . Housing 12 preferably includes a case 66 that houses stator 14B and rotor 14A. The case 66 contains at least one of aluminum alloy and resin, for example. Case 66 is attached to first housing 32 . The case 66 is attached to the side of the first housing 32 opposite to the side to which the second housing 34 is attached in the direction parallel to the rotation center axis C1 of the motor 14 . Case 66 is preferably attached to first portion 12</b>C contained in first housing 32 . The first portion 12C extends along a direction orthogonal to the rotation center axis C1 of the motor 14. As shown in FIG. 12 C of 1st parts contain the through-hole 12B.

If the motor 14 is an inner rotor type motor, the stator 14B is provided on the inner circumference of the case 66 . Motor 14 may be an outer rotor type motor. A first portion 12C including the through hole 12B of the housing 12 divides the accommodation space S into a first space S1 and a second space S2. The first space S1 includes the rotor 14A and the stator 14B. The speed reducer 52, the crankshaft 36, the electric circuit board 16, and the heat conducting section 20 are provided in the second space S2. A first end 50A of the output shaft 50 is arranged in the first space S1, and a second end 50B is arranged in the second space S2. The first end 50A is supported by the housing 12 via a fourth bearing 68. As shown in FIG. The first end portion 50A is preferably supported by the case 66 via the fourth bearing 68 . A speed reducer 52 is connected to the second end 50B. A middle portion of the output shaft 50 is supported by the housing 12 via a fifth bearing 70 . An intermediate portion of the output shaft 50 is supported by the first portion 12C via a fifth bearing 70. As shown in FIG. Fourth bearing 68 and fifth bearing 70 include, for example, radial ball bearings.

A portion of housing 12 is provided between rotor 14A and stator 14B and electrical circuit board 16 . Preferably, a first portion 12C of housing 12 is provided between rotor 14A and stator 14B and electrical circuit board 16 . The electric circuit board 16 preferably extends along a direction orthogonal to the rotation center axis C1 of the motor 14 . The electrical circuit board 16 preferably includes a recess 16A in which an intermediate portion of the output shaft 50 is arranged. The electrical circuit board 16 includes a printed wiring board. The electric circuit board 16 has a first board surface 22 and a second board surface 24 in the thickness direction.

The fixing portion 18 of the electric circuit board 16 is preferably provided near the edge of the electric circuit board 16 . The electrical circuit board 16 preferably includes a plurality of fixed portions 18 . The fixed portion 18 preferably includes holes 18A. The electric circuit board 16 is attached to the housing 12 and fixed in the housing space S by inserting the bolt B into the hole 18A and screwing it into the female thread provided in the housing 12 . A female threaded portion 64 for attaching the electric circuit board 16 to the housing 12 is provided, for example, in the first housing 32 . The female threaded portion 64 may be provided on the second housing 34 .

The control circuit 26 comprises a drive circuit for the motor 14 and a controller configured to control the motor 14 . The drive circuit may be included in the controller. The control unit includes an arithmetic processing unit 72A that executes a predetermined control program. The arithmetic processing unit 72A includes, for example, a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). The controller may include one or more microcomputers. The control unit may further include a storage unit. The storage unit stores various control programs and information used for various control processes. The storage unit includes, for example, non-volatile memory and volatile memory. The drive circuit includes an inverter circuit 72B. The drive circuit controls power supplied to the motor 14 from the battery unit. The driving circuit is communicably connected to the control unit by an electric wire or a wireless communication device. The drive circuit drives the motor 14 according to the control signal from the control section.

Control circuit 26 includes a plurality of electronic elements 72 . The plurality of electronic elements 72 include an arithmetic processing unit 72A and switching elements that constitute an inverter circuit 72B. The plurality of electronic elements 72 may further include resistive elements, converter ICs 72C, capacitors 72D, and the like. The plurality of electronic elements 72 are preferably partially provided on the first substrate surface 22 and the remainder are provided on the second substrate surface 24 . All of the plurality of electronic elements 72 may be provided on the first substrate surface 22 or the second substrate surface 24 .

The heat-conducting portion 20 includes a material with higher thermal conductivity than air. The first heat-conducting portion 28 includes a material with higher thermal conductivity than air. The heat conducting part 20 preferably contains at least one of an elastic body and a viscous fluid. The elastic body includes a heat transfer sheet. The heat transfer sheet includes, for example, silicone, acrylic, carbon fiber, or the like. The thermal conductivity of the heat transfer sheet preferably ranges from 0.5 W/m·K to 50 W/m·K. Viscous fluids include grease. Grease includes, for example, silicone oil. The grease may contain metal particles. The thermal conductivity of the grease preferably ranges from 0.5 W/m.K to 10 W/m.K. The heat conducting portion 20 may contain silicone. The first heat conducting portion 28 and the second heat conducting portion 30 may contain different materials. The heat conducting portion 20 may include a plurality of first heat conducting portions 28 . The heat conducting part 20 may include a plurality of second heat conducting parts 30 . At least one of the plurality of first heat conducting portions 28 may contain a different material. At least one of the plurality of second heat conducting parts 30 may contain a different material.

The first heat conducting portion 28 preferably contacts the first housing 32 . The second heat conducting portion 30 preferably contacts the second housing 34 . A portion 12D of the first housing 32 that contacts the first heat conducting portion 28 preferably includes a thick portion. A portion 12D of the first housing 32 that contacts the first heat conducting portion 28 is preferably included in the first portion 12C. A portion of the second housing 34 that contacts the second heat conducting portion 30 preferably includes a thick portion. The heat conducting part 20 preferably contacts the electronic element 72 that generates the largest amount of heat among the plurality of electronic elements 72 . At least one of the first heat-conducting portion 28 and the second heat-conducting portion 30 of the heat-conducting portion 20 preferably contacts the electronic element 72 that generates the largest amount of heat among the plurality of electronic elements 72 . The electronic element 72 that generates the largest amount of heat among the plurality of electronic elements 72 is, for example, the switching element of the inverter circuit 72B or the capacitor 72D. The electronic element 72 that generates the largest amount of heat among the plurality of electronic elements 72 can be determined in advance by testing or the like. For example, when the motor 14 is operated at rated speed, the electronic element 72 having the highest temperature among the plurality of electronic elements 72 is determined as the electronic element 72 having the largest amount of heat generation. When at least some of the plurality of electronic elements 72 are provided on the first substrate surface 22 , the first heat conducting part 28 may contact the electronic element 72 that generates the most heat on the first substrate surface 22 . . When at least some of the plurality of electronic elements 72 are provided on the second substrate surface 24 , the first thermally conductive portion 28 is provided on the back side of the portion corresponding to the electronic element 72 that generates the largest amount of heat on the second substrate surface 24 . may contact the portion of the first substrate surface 22 located at . When at least some of the plurality of electronic elements 72 are provided on the second substrate surface 24 , the second thermal conduction part 30 is arranged to contact the electronic element 72 that generates the largest amount of heat on the second substrate surface 24 . good too. When at least some of the plurality of electronic elements 72 are provided on the first substrate surface 22 , the second thermally conductive portion 30 is provided on the back side of the portion corresponding to the electronic element 72 that generates the largest amount of heat on the first substrate surface 22 . may be in contact with the portion of the second substrate surface 24 located at .

At least part of the first heat conducting portion 28 preferably overlaps at least one of the rotor 14A and the stator 14B when viewed from the axial direction of the rotor 14A. When the heat-conducting portion 20 includes a plurality of first heat-conducting portions 28, at least a portion of at least one first heat-conducting portion 28 is preferably located between the rotor 14A and the stator 14B when viewed from the axial direction of the rotor 14A. overlap at least partially. At least part of the first heat conducting portion 28 may overlap both the rotor 14A and the stator 14B when viewed from the axial direction of the rotor 14A. At least part of the second heat conducting portion 30 preferably overlaps at least one of the rotor 14A and the stator 14B when viewed from the axial direction of the rotor 14A. When the heat-conducting portion 20 includes a plurality of second heat-conducting portions 30, at least a portion of at least one second heat-conducting portion 30 is preferably located between the rotor 14A and the stator 14B when viewed from the axial direction of the rotor 14A. overlap at least partially. At least part of the second heat conducting portion 30 may overlap both the rotor 14A and the stator 14B when viewed from the axial direction of the rotor 14A.

At least a portion of the first heat conducting portion 28 and the second heat conducting portion 30 may be offset when viewed from the axial direction of the rotor 14A. As viewed from the axial direction of the rotor 14A, the first heat conducting portion 28 and the second heat conducting portion 30 may be arranged so as to be offset as a whole. The area of the first heat conducting portion 28 may be smaller than the area of the second heat conducting portion 30 when viewed from the axial direction of the rotor 14A. The area of the first heat conducting portion 28 may be equal to or larger than the area of the second heat conducting portion 30 when viewed from the axial direction of the rotor 14A. When viewed from the axial direction of the rotor 14A, the heat conducting portion 20 is provided at a position closer to the rotation center axis C1 of the motor 14 than the fixed portion 18, for example. When the heat conducting portion 20 includes a plurality of first heat conducting portions 28, all of the plurality of first heat conducting portions 28 are closer to the rotation center axis of the motor 14 than the fixed portion 18 when viewed from the axial direction of the rotor 14A. It may be provided at a position close to C1. When the heat conducting portion 20 includes a plurality of second heat conducting portions 30, all of the plurality of second heat conducting portions 30 are closer to the rotation center axis of the motor 14 than the fixed portion 18 when viewed from the axial direction of the rotor 14A. It may be provided at a position close to C1.

A space S3 is formed between a portion 12D of the housing 12 with which the first heat conducting portion 28 contacts, the rotor 14A and the stator 14B. A space S3 is formed between a portion 12D of the housing 12 with which the first heat conducting portion 28 contacts, the rotor 14A and the stator 14B in a direction parallel to the rotation center axis of the rotor 14A. The space S3 is formed within the first space S1. A space S3 is formed in the first space S1 between the rotor 14A and the stator 14B and the first portion 12C.

Drive unit 10 preferably further includes a torque sensor 74 . The torque sensor 74 is configured to output a signal corresponding to the torque of the manpower driving force. The torque sensor 74 is provided in the housing 12, for example. The torque sensor 74 is configured to output a signal corresponding to the torque of the human power driving force input to the crankshaft 36, for example. For example, when a first one-way clutch is provided in the power transmission path, the torque sensor 74 is provided upstream of the first one-way clutch in the power transmission path. Torque sensor 74 includes, for example, a magnetostrictive sensor or a strain sensor. Strain sensors include metal strain gauges, semiconductor strain gauges, and the like. When the torque sensor 74 includes a strain sensor, the strain sensor is provided on the outer peripheral portion of the output portion 38 or a member connecting the output portion 38 and the crankshaft 36 . When the torque sensor 74 includes a strain sensor, a magnetostrictive element is formed on the outer peripheral surface of the crankshaft 36 or the output portion 38 and the magnetostrictive sensor is arranged on the outer periphery of the crankshaft 36 or the output portion 38 . Torque sensor 74 may include wireless or wired communication. The communication section of the torque sensor 74 is configured to be able to communicate with the control section of the motor 14 . The communication section of the torque sensor 74 may be provided on a circuit board 76 different from the electric circuit board 16 .

(Modification)
The description of the embodiments is an illustration of the forms that a drive unit for a manpowered vehicle according to the invention can take, and is not intended to be limiting of the forms. A drive unit for a manpowered vehicle according to the present invention may take the form of, for example, the variants of the embodiments shown below, and combinations of at least two variants not contradicting each other. In the following modified examples, the same reference numerals as in the embodiment are given to the parts that are common to the embodiment, and the description thereof is omitted.

- As shown in FIG. 3 , the first portion 12C may be formed separately from the first housing 32 . If the first portion 12C is formed separately from the first housing 32, the first portion 12C may be integrally molded with at least a portion of the case 66.

- The case 66 may be integrally formed with one of the first housing 32 and the second housing 34 .

- The housing 12 may include members other than the first housing 32 , the second housing 34 , and the case 66 . In short, as long as the housing 12 is provided with the motor 14 and the electric circuit board 16 is arranged in the accommodation space S, the shape and configuration can be changed as appropriate.

- The case 66 may be attached to the second housing 34 . When the case 66 is attached to the second housing 34, the motor 14 preferably has the first end 50A and the second end 50B of the output shaft 50 relative to the drive unit 10 shown in FIG. The motor 14 is reversed in the housing 12 so as to be opposite in the axial direction, and the second housing 34 is provided with a hole for passing the output shaft 50 therethrough. When the case 66 is attached to the second housing 34, a space is formed between the portion of the housing 12 with which the second heat conducting portion 30 contacts and the rotor 14A and the stator 14B.

- The second heat conducting portion 30 may be omitted from the heat conducting portion 20 . When the second heat conducting portion 30 is omitted from the heat conducting portion 20, the drive unit 10 controls the housing 12 having the accommodation space S, the motor 14 provided in the housing 12, the first substrate surface 22, and the motor 14. The electric circuit board 16 having the control circuit 26 and arranged in the accommodation space S, the fixing portion 18 for fixing the electric circuit board 16 in the accommodation space S, and the fixing portion 18 are different from the electric circuit board 16 and the fixing portion 18 . a heat conducting portion 20 for conducting heat of the electric circuit board 16 to the housing 12 by contacting the housing 12, the heat conducting portion 20 being a first heat conducting portion provided between the electric circuit board 16 and the motor 14; A heat conducting portion 28 is included. In this variation, the first heat conducting portion 28 may contact the first housing 32 or may contact the second housing 34 .

- The motor 14 may be provided so as to transmit rotation to the power transmission path of the human-powered driving force including from the pedals to the rear wheels, or to the front wheels. For example, the motor 14 may be provided on the hub of the rear wheel or may be provided on the hub of the front wheel. The present invention can be applied even when the motor 14 is provided on the hub of the front wheel or the hub of the rear wheel.

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

DESCRIPTION OF SYMBOLS 10... Drive unit, 12... Housing, 12B... Through hole, 12C... First part, 12D... Part, 14... Motor, 14A... Rotor, 14B... Stator, 16... Electric circuit board, 18... Fixed part, 20... Heat conduction Parts 22... First substrate surface 24... Second substrate surface 26... Control circuit 28... First heat conducting part 30... Second heat conducting part 32... First housing 34... Second housing 36 ... crankshaft, 50 ... output shaft, 66 ... case, 72 ... electronic element.

Claims (18)

A drive unit for a human-powered vehicle,
a housing having an accommodation space;
a motor mounted in the housing and configured to provide propulsion to the manpowered vehicle;
an electric circuit board having a first board surface, a second board surface opposite to the first board surface, and a control circuit for controlling the motor, and arranged in the accommodation space;
a fixing part for fixing the electric circuit board in the housing space;
a heat conducting part that conducts heat of the electric circuit board to the housing by being in contact with the electric circuit board and the housing, different from the fixed part;
The heat conducting part is
a first heat conducting part provided between the first substrate surface and the housing;
a second thermally conductive portion provided between the second substrate surface and the housing;
the motor includes an output shaft;
the housing includes a through hole through which the output shaft passes and a predetermined portion surrounding the through hole,
The drive unit , wherein the first heat conducting portion is in contact with the predetermined portion . A drive unit for a human-powered vehicle,
a housing having an accommodation space;
a motor provided in the housing;
an electric circuit board having a control circuit for controlling the motor and arranged in the accommodation space;
a fixing part for fixing the electric circuit board in the housing space;
a heat conducting part that conducts heat of the electric circuit board to the housing by being in contact with the electric circuit board and the housing, different from the fixed part;
The thermally conductive part includes a first thermally conductive part provided between the electric circuit board and the motor,
the motor includes an output shaft;
the housing includes a through hole through which the output shaft passes and a predetermined portion surrounding the through hole,
The drive unit , wherein the first heat conducting portion is in contact with the predetermined portion . The electric circuit board has a first substrate surface and a second substrate surface opposite to the first substrate surface,
The first heat conducting part is provided between the first substrate surface and the housing,
3. The drive unit according to claim 2, wherein said heat conducting portion further comprises a second heat conducting portion provided between said second substrate surface and said housing. the housing includes a first housing and a second housing;
the first heat conducting part is in contact with the first housing;
4. The drive unit according to claim 1, wherein said second heat conducting portion contacts said second housing. the motor includes a rotor and a stator;
5. The drive unit according to any one of claims 1 to 4, wherein a portion of said housing is provided between said rotor and said stator and said electric circuit board. the motor includes a rotor and a stator;
a portion of the housing is provided between the rotor and the stator and the electrical circuit board;
5. The drive unit according to any one of claims 1, 3, and 4, wherein at least part of said second heat conducting portion overlaps at least one of said rotor and said stator when viewed from the axial direction of said rotor. . 7. The drive unit according to claim 5, wherein a space is formed between a portion of said housing with which said first heat conducting portion contacts and said rotor and said stator. 8. The drive unit according to any one of claims 5 to 7, wherein at least part of said first heat conducting portion overlaps with at least one of said rotor and said stator when viewed from the axial direction of said rotor. The drive unit according to any one of claims 5 to 8, wherein said housing includes a case that accommodates said stator and said rotor. The electric circuit board extends along a direction orthogonal to the rotation center axis of the motor, and the first gear provided on the output shaft of the motor is arranged in the direction in which the rotation center axis of the motor extends. 10. A drive unit according to any one of claims 1 to 9, provided in a range where further comprising a second gear provided on a first transmission shaft provided at a portion different from the output shaft of the motor and meshing with the first gear;
The electric circuit board is provided in a range in which the second gear is arranged in a direction in which the center axis of rotation of the motor extends, and is located apart from the second gear when viewed from the center axis of rotation of the motor. 11. A drive unit according to claim 10, arranged so as not to overlap. The fixing portion is provided in plurality on the outer peripheral portion of the electric circuit board,
12. The drive unit according to any one of claims 1 to 11, wherein said heat conducting portion is arranged at a position closer to the rotation center axis of said motor than said fixing portion. The control circuit includes a plurality of electronic elements,
13. The drive unit according to any one of claims 1 to 12 , wherein said heat conducting portion contacts an electronic element that generates the largest amount of heat among said plurality of electronic elements. 14. A drive unit as claimed in any preceding claim, further comprising a crankshaft provided in the housing. 12. The drive unit according to any one of claims 1 to 11 , wherein said heat conducting portion includes at least one of an elastic body and a viscous fluid. 16. The drive unit according to claim 15 , wherein said elastic body includes a heat transfer sheet. 17. A drive unit according to claim 15 or 16 , wherein said viscous fluid comprises grease. 18. The drive unit according to any one of claims 15 to 17 , wherein said heat conducting portion comprises silicone.

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