Motor unit and electric vehicle

Abstract

To provide a motor unit having high motor efficiency.SOLUTION: A motor unit 100 used for an electric vehicle includes a substrate 150, a motor 110 having a connector 111a, and a connector 250a directly attached to the substrate 150. The terminal 111a and the connector 250a are connected to each other by inserting one into the other in a direction parallel to the rotation axis of the motor 110.SELECTED DRAWING: Figure 4

Description

[Technical Field]

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

[0002] Patent Document 1 discloses a motor unit for use in an electric bicycle. The motor unit disclosed in Patent Document 1 includes a circuit board, a motor having terminals, and a current-carrying member. The current-carrying member includes a harness connected at one end to the circuit board and a connector connected at the other end of the harness, and the terminals of the motor are connected to the connector. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7246001 Summary of the Invention [Problem to be solved by the invention]

[0004] The conventional motor unit described above has a problem in that the motor efficiency is reduced due to the influence of heat generated in the harness.

[0005] Therefore, an object of the present invention is to provide a motor unit with high motor efficiency and an electric vehicle equipped with such a motor unit. [Means for solving the problem]

[0006] A motor unit according to one aspect of the present invention is a motor unit for use in an electric vehicle, and comprises a substrate, a motor having terminals, and a connector attached directly to the substrate, the terminals and the connector being connected to each other by inserting one into the other in a direction parallel to the rotational axis of the motor.

[0007] An electric vehicle according to one aspect of the present invention includes the motor unit according to the above aspect, wheels to which rotational force of the motor is transmitted, and a frame that supports the motor unit and the wheels. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a motor unit with high motor efficiency and an electric vehicle equipped with the motor unit. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a side view of an electric bicycle equipped with a motor unit according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the motor unit according to the embodiment. [Figure 3] FIG. 3 is a partially exploded perspective view of the motor unit according to the embodiment. [Figure 4] FIG. 4 is an enlarged perspective view showing the connection between the terminals and the connector in the motor unit according to the embodiment. [Figure 5] FIG. 5 is an enlarged plan view showing the positional relationship between the motor shaft, terminals, and connectors in the motor unit according to the embodiment. [Figure 6] FIG. 6 is a perspective view of a connector included in the motor unit according to the embodiment. [Figure 7] FIG. 7 is an enlarged plan view showing the positional relationship between the terminals and the connector in the motor unit according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] A motor unit and an electric vehicle according to embodiments of the present invention will be described in detail below with reference to the drawings. Note that each of the embodiments described below represents a specific example of the present invention. Therefore, the numerical values, shapes, materials, components, component arrangements and connection forms, steps, and step sequences shown in the following embodiments are merely examples and are not intended to limit the present invention. Therefore, among the components in the following embodiments, components not recited in independent claims will be described as optional components.

[0011] Furthermore, each figure is a schematic diagram and is not necessarily an exact illustration. Therefore, for example, the scales of the figures do not necessarily match. Furthermore, in each figure, substantially the same components are given the same reference numerals, and redundant explanations are omitted or simplified.

[0012] Furthermore, in this specification, terms indicating the relationship between elements, such as parallel or perpendicular, terms indicating the shape of elements, such as rectangular or circular, and numerical ranges are not expressions that only express a strict meaning, but are expressions that also include a substantially equivalent range, for example, a difference of about a few percent.

[0013] Furthermore, in this specification, ordinal numbers such as "first" and "second" do not refer to the number or order of components unless otherwise specified, but are used for the purpose of avoiding confusion and distinguishing between components of the same type.

[0014] In addition, in this specification, "forward" refers to the direction in which an electric vehicle travels during normal driving, and "rearward" refers to the opposite direction. Specifically, in the case of an electric bicycle, the direction in which the handlebars are positioned relative to the saddle is "forward." "Forward-backward direction" refers to the direction from rear to forward, and the opposite direction, among multiple horizontal directions (any direction parallel to the ground). "Right-left direction" refers to the direction perpendicular to the forward-backward direction, and when facing forward, the left side is the "left" and the right side is the "right."

[0015] (Embodiment) [composition] First, the configuration of an electric bicycle according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a side view showing the configuration of an electric bicycle 1 equipped with a motor unit 100 according to this embodiment.

[0016] The electric bicycle 1 shown in Fig. 1 is an example of an electric vehicle and is a bicycle with an electric assist function. The electric assist function is a function that assists the forward movement of the electric bicycle 1 based on the force applied to the pedals 17 by the user riding the electric bicycle 1, and is executed in a so-called assist mode.

[0017] As shown in FIG. 1, the electric bicycle 1 includes a body 10, a battery 20, and a motor unit 100.

[0018] The body 10 is the main body of the electric bicycle 1. The body 10 includes a frame 11, a front wheel 12, a rear wheel 13, a handlebar 14, a saddle 15, cranks 16, pedals 17, a chain 18, a front sprocket 19a, and a rear sprocket 19b.

[0019] The frame 11 is the skeleton of the electric bicycle 1. The frame 11 is made of, for example, metal, carbon, or synthetic resin. The frame 11 is formed by combining multiple tubular members such as a head tube, a down tube, a seat tube, a chainstay, and a front fork. The frame 11 may have a shock-absorbing member such as a suspension. The frame 11 supports a front wheel 12, a rear wheel 13, a handlebar 14, a saddle 15, a crank 16, a chain 18, a front sprocket 19a, and a rear sprocket 19b.

[0020] The front wheels 12 have tires for the vehicle body 10 to travel on. The front wheels 12 are the front wheels of two wheels aligned in the front-to-rear direction. The front wheels 12 are supported by the frame 11 so that they can rotate around an axis extending in the left-to-right direction. The front wheels 12 may receive power from the motor unit 100, i.e., the rotational force of the motor 110 (see FIG. 2).

[0021] The rear wheel 13 has a tire for driving the vehicle body 10. The rear wheel 13 is the rear wheel of two wheels aligned in the front-to-rear direction. The rear wheel 13 is supported by the frame 11 so that it can rotate about an axis extending in the left-to-right direction. In this embodiment, the rear wheel 13 receives power from the motor unit 100, i.e., the rotational force of the motor 110. The rear wheel 13 is connected to a front sprocket 19a via a chain 18 and a rear sprocket 19b.

[0022] The handlebars 14 are operated by a user riding the electric bicycle 1 to change the steering angle of the electric bicycle 1. The handlebars 14 are rotatably supported by the frame 11. A pair of grips and a pair of brake levers are provided at both ends of the handlebars 14. The pair of grips are held by the user's hands when the user is riding the electric bicycle 1 in an appropriate posture. The pair of grips are also held by the hands when pushing or supporting the electric bicycle 1 and walking, and receive forward pushing force, etc. The pair of brake levers apply mechanical braking force to the front wheel 12 and rear wheel 13, for example, by operating a brake device.

[0023] The saddle 15 is a portion on which a user sits. The saddle 15 is attached to the frame 11 so that the height thereof can be adjusted.

[0024] The crank 16 has a crankshaft 16a and a pair of crank arms 16b. The crank arms 16b are provided on both the left and right sides of the motor unit 100, and are fixed to both ends of the crankshaft 16a, which extends in the left-right direction. One end of the crank arm 16b is rotatably fixed to the crankshaft 16a, and the pedal 17 is rotatably fixed to the other end of the crank arm 16b.

[0025] The pedals 17 receive a pedaling force from the user riding the electric bicycle 1. The pedals 17 are attached to the longitudinal ends of each crank arm 16b on the opposite side from the crank shaft 16a. The pedals 17 are attached to the crank arms 16b so as to be rotatable relative to the crank arms 16b. The rotation axis of the pedals 17 is approximately parallel to the rotation axis of the crank shaft 16a of the crank 16.

[0026] When a pedaling force is applied to the pedal 17, the crank arm 16b rotates around the crank shaft 16a, and the manual driving force resulting from this rotation is transmitted to the rear wheel 13 via the front sprocket 19a, the chain 18, and the rear sprocket 19b. When the electric bicycle 1 operates in the assist mode, the manual driving force based on the pedaling force and the auxiliary driving force of the motor 110 added to the manual driving force are transmitted to the rear wheel 13.

[0027] The chain 18 is an example of a power transmission member that transmits the rotational force of the front sprocket 19a to the rear sprocket 19b. The chain 18 connects the front sprocket 19a and the rear sprocket 19b. Note that instead of the chain 18, a belt, a shaft, a wire, a gear, or the like may be used as the power transmission member. For example, when the power transmission member is a belt, compared to when the power transmission member is a chain 18, effects such as quieter operation, improved durability, and reduced maintenance frequency can be expected.

[0028] The front sprocket 19a is attached to the crankshaft 16a of the crank arm 16b. When the user steps on the pedal 17, the front sprocket 19a rotates via the crank arm 16b and the crankshaft 16a. The rotational force of the front sprocket 19a is transmitted to the rear sprocket 19b attached to the rear wheel 13 via the chain 18. This causes the rear sprocket 19b to rotate, and the rear wheel 13 to rotate. The front sprocket 19a is also called the drive sprocket, and the rear sprocket 19b is also called the driven sprocket.

[0029] The battery 20 is a storage battery that stores power for driving the motor 110 of the motor unit 100. The battery 20 is, for example, a secondary battery, but may also be another charge / discharge element such as a capacitor. The battery 20 is electrically connected to the motor 110 and supplies power to the motor 110.

[0030] The battery 20 is removably fixed to the frame 11. There are no particular limitations on the mounting position of the battery 20. Furthermore, if the electric bicycle 1 is equipped with lighting devices such as a headlight and a taillight, and electronic devices such as a display unit, an operation unit (hand switch), and an electric gearbox, the battery 20 can also supply power to these lighting devices and electronic devices.

[0031] The motor unit 100 is an example of a motor unit used in an electric vehicle. As shown in Fig. 2, the motor unit 100 includes a motor (first rotation mechanism) 110, a crank rotation mechanism (second rotation mechanism) 120, a speed reduction mechanism (third rotation mechanism) 130, a crank rotation sensor unit (fourth rotation mechanism) 140, a substrate 150, a case 160, and a control circuit 170. Fig. 2 is a cross-sectional view of the motor unit 100 according to this embodiment. Fig. 2 shows a cross section including the center of the crankshaft 16a and the center of the motor shaft 113 of the motor 110.

[0032] The motor 110 is an example of a first rotation mechanism having a motor shaft 113. The motor 110 is an electric motor that receives power from the battery 20 and is driven based on the control of a control circuit provided on the substrate 150. As shown in FIG. 2 , the motor 110 has a stator 111, a rotor 112, and a motor shaft (output shaft) 113.

[0033] The motor 110 is supported by a case 160 so that the rotor 112 and motor shaft 113 can rotate via bearings. Specifically, the stator 111 receives power from the battery 20 and rotates the rotor 112. The motor shaft 113 rotates in accordance with the rotation of the rotor 112. A toothed portion 114 is provided on the tip side of the motor shaft 113, and is engaged with a large diameter gear 131 of the reduction mechanism 130. The rotation of the toothed portion 114 causes the large diameter gear 131 to rotate.

[0034] The crank rotation mechanism 120 is an example of a second rotation mechanism having a crankshaft 16a. The crankshaft 16a is provided to pass through the case 160. The crankshaft 16a is rotatably supported by a bearing. The crank rotation mechanism 120 includes a human power transmission body 121, an intermediate cylinder 122, and an interlocking body 123. The human power transmission body 121, the intermediate cylinder 122, and the interlocking body 123 are all cylindrical members, and the crankshaft 16a is inserted into the cylinders.

[0035] The power transmitting body 121 is fitted into a serration portion 124 provided on the crankshaft 16a, and is provided to rotate integrally with the crankshaft 16a. The intermediate cylinder 122 is provided rotatably relative to the crankshaft 16a, and is provided to rotate integrally with each of the power transmitting body 121 and the interlocking body 123. A front sprocket 19a (not shown in FIG. 2) is provided on the interlocking body 123 so as to rotate integrally with the interlocking body 123. The power transmitting body 121, the intermediate cylinder 122, and the interlocking body 123 are each provided with one or more serration portions (spline portions), and are fitted together to rotate integrally.

[0036] Furthermore, a one-way clutch (not shown) is disposed between the intermediate cylinder 122 and the interlocking body 123. The one-way clutch is disposed on the intermediate cylinder 122, and transmits rotational force in one direction from the intermediate cylinder 122 to the interlocking body 123 by a ratchet engaging with the interlocking body 123.

[0037] With this configuration, the crankshaft 16a is rotated by the force applied to the pedal 17, and the manual driving force generated by this rotation is transmitted to the front sprocket 19a via the manual power transmission body 121, the intermediate cylinder body 122, the one-way clutch (not shown), and the interlocking body 123. When the front sprocket 19a is rotated by the manual driving force, the chain 18 attached to the front sprocket 19a rotates, causing the rear sprocket 19b and the rear wheel 13 to rotate.

[0038] Additionally, an auxiliary driving force from the motor 110 is transmitted to the interlocking body 123 via the speed reducer 130. In other words, the rotation of the interlocking body 123 can be assisted by the auxiliary driving force from the motor 110, so that the front sprocket 19a, the rear sprocket 19b, and the rear wheel 13 can be rotated in accordance with the rotation of the interlocking body 123.

[0039] The reduction mechanism 130 is an example of a third rotation mechanism having a gear that transmits rotational force from the motor 110 to the crank rotation mechanism 120. The reduction mechanism 130 is configured so that the rotational torque of the motor 110 (i.e., the auxiliary driving force) is amplified and transmitted to the interlocking body 123. Specifically, as shown in FIG. 2 , the reduction mechanism 130 has a large diameter gear 131 and a small diameter gear 132. As described above, the large diameter gear 131 rotates in response to the rotation of the motor shaft 113 of the motor 110.

[0040] In the reduction mechanism 130, the small diameter gear 132 rotates integrally with the large diameter gear 131 on the same rotation axis. The small diameter gear 132 fits into the gear portion of the interlocking body 123. When the small diameter gear 132 rotates, the interlocking body 123 rotates.

[0041] As described above, in this embodiment, the auxiliary driving force generated by the motor 110 is transmitted to the interlocking member 123 via the reduction gear mechanism 130. That is, when the rotor 112 and the motor shaft 113 of the motor 110 rotate, the interlocking member 123 also rotates, causing the front sprocket 19a to rotate. This causes the rear wheel 13 to rotate via the chain 18 and the rear sprocket 19b.

[0042] The crank rotation sensor unit 140 is an example of a fourth rotation mechanism having a sensor shaft for detecting the rotation of the crankshaft 16a. Specifically, the crank rotation sensor unit 140 has a gear-shaped rotor 141 having the sensor shaft as its rotation axis, and a photodetector (not shown). The rotor 141 of the crank rotation sensor unit 140 is provided to rotate integrally with the intermediate cylinder body 122.

[0043] The rotation of the rotor 141 is detected by a detector such as a photodetector. For example, the photodetector has a light-emitting portion and a light-receiving portion arranged to face each other. The light-emitting portion and the light-receiving portion are fixed to, for example, the substrate 150 or the case 160. The rotor 141 is positioned so that its teeth block the path of light from the light-emitting portion to the light-receiving portion. As the rotor 141 rotates, the teeth block the light, so the rotation speed of the rotor 141 is detected based on the number of times the light received by the light-receiving portion is blocked (or the number of times light is successfully received) and the number of teeth on the rotor 141. Because the rotor 141, the intermediate cylinder 122, and the crankshaft 16a rotate integrally, the rotation speed of the rotor 141 coincides with the rotation speed of the crankshaft 16a. In this way, the crank rotation sensor 140 can detect the rotation speed of the crankshaft 16a.

[0044] The crank rotation sensor unit 140 may have any configuration as long as it can detect the rotation speed of the crankshaft 16a. The motor unit 100 may also include a motor rotation sensor that detects the rotation speed of the motor 110. The motor unit 100 may also include a pedal force sensor that detects the human driving force generated by the rotation of the crankshaft 16a based on the pedal force applied to the pedal 17.

[0045] The substrate 150 is a substrate on which various electronic components that constitute the control circuit 170 for controlling the operation of the motor unit 100 are mounted. The electronic components include one or more integrated circuits including a power supply IC (Integrated Circuit), electrolytic capacitors, capacitors, transistors, diodes, resistive elements, connectors, etc. The substrate 150 is, for example, a printed wiring board. Metal wiring is provided on the substrate 150 to electrically connect the electronic components.

[0046] The substrate 150 has a first main surface 150a and a second main surface 150b opposite the first main surface 150a. The first main surface 150a and the second main surface 150b are a pair of flat surfaces parallel to each other. As shown in FIG. 2, a plurality of electronic components are mounted on the first main surface 150a. The stator 111 and rotor 112 of the motor 110 are disposed on the second main surface 150b side of the substrate 150. The motor shaft 113 and crankshaft 16a of the motor 110 are disposed so as to perpendicularly intersect with the substrate 150. The four rotation mechanisms (motor 110, crank rotation mechanism 120, reduction mechanism 130, and crank rotation sensor unit 140) included in the motor unit 100 are disposed so that their rotation axes are perpendicular to the first main surface 150a of the substrate 150. The substrate 150 is fixed to the case 160 using fastening members such as screws.

[0047] The case 160 constitutes most of the outer shell of the motor unit 100. The circuit board 150 is housed and fixed in the case 160. The case 160 also houses the motor 110, the reduction mechanism 130, the crank rotation sensor unit 140, and part of the crank rotation mechanism 120. The crank shaft 16a of the crank rotation mechanism 120 is disposed so as to pass through the case 160. Both ends of the crank shaft 16a are located outside the case 160, and are connected to crank arms 16b.

[0048] The case 160 includes a first divided body 161 and a second divided body 162. The first divided body 161 and the second divided body 162 are assembled and fixed together with fastening members (not shown) such as screws to form the case 160. Specifically, the first divided body 161 and the second divided body 162 are each formed in a cylindrical shape with a bottom, and are arranged with their openings facing each other and with the leading ends of their outer peripheral walls facing each other. The leading ends of the outer peripheral walls are provided with flanges with through holes, and the first divided body 161 and the second divided body 162 are fixed together with screws inserted into the through holes. Note that a packing or the like may be provided between the leading ends of the outer peripheral walls of the first divided body 161 and the second divided body 162 to prevent moisture and the like from entering.

[0049] The first divided body 161 and the second divided body 162 are each formed using a metal material such as an aluminum alloy, a magnesium alloy, stainless steel, or steel, but may also be formed using carbon or resin. The first divided body 161 and the second divided body 162 are each integrally formed by die casting, injection molding, or the like.

[0050] The control circuit 170 is mounted on the substrate 150. The control circuit 170 includes a power supply circuit that generates power to be supplied to the motor 110, i.e., power for rotating the motor shaft 113. For example, the power supply circuit is a power supply IC including a linear regulator or a DC / DC converter. The power supply circuit generates power to be supplied to the motor 110 based on power from the battery 20. Furthermore, if the electric bicycle 1 is equipped with lighting devices such as a headlight and a taillight, and electronic devices such as a display unit, an operation unit (hand switch), and an electric gearbox, the power supply circuit may generate power to be supplied to these lighting devices and electronic devices based on power from the battery 20.

[0051] The control circuit 170 also includes a detection circuit that detects the rotation of the crankshaft 16a based on the rotation of the rotor 141 of the crank rotation sensor unit 140. For example, the detection circuit includes the above-mentioned photodetector. The control circuit 170 may also include circuits for controlling lighting devices such as a headlight and a taillight provided on the electric bicycle 1, as well as electronic devices such as a display unit, an operating unit (hand switch), and an electric transmission.

[0052] [Main characteristic configuration] Next, the main characteristic configuration of the motor unit 100 according to this embodiment will be described with reference to FIGS.

[0053] FIG. 3 is a partially exploded perspective view of the motor unit 100 according to the embodiment. Specifically, FIG. 3 shows a portion of the circuit board 150, the stator 111 of the motor 110, and connectors 250a, 250b, and 250c directly attached to the circuit board 150. FIG. 4 is an enlarged perspective view showing the connection between the terminals 111a, 111b, and 111c of the stator 111 and the connectors 250a, 250b, and 250c in the motor unit 100 according to the embodiment. FIG. 5 is an enlarged plan view showing the positional relationship between the motor shaft 113, the terminals 111a, 111b, and 111c of the stator 111, and the connectors 250a, 250b, and 250c in the motor unit 100 according to the embodiment. FIG. 6 is a perspective view of the connector 250a included in the motor unit 100 according to the embodiment. FIG. 7 is an enlarged plan view showing the positional relationship between the terminal 111a of the stator 111 and the connector 250a in the motor unit 100 according to the embodiment.

[0054] As shown in Fig. 3, the motor unit 100 includes a plurality of connectors 250a, 250b, and 250c. Also, as shown in Fig. 3, the stator 111 of the motor 110 has a plurality of terminals 111a, 111b, and 111c. The connectors 250a, 250b, and 250c correspond one-to-one to the terminals 111a, 111b, and 111c.

[0055] Specifically, connector 250a and terminal 111a correspond to each other, and are connected to each other by being inserted into the other in a direction parallel to the rotational axis of motor 110 (i.e., the axial direction of motor shaft 113). Similarly, connector 250b and terminal 111b correspond to each other and are connected to each other. Furthermore, connector 250c and terminal 111c correspond to each other and are connected to each other.

[0056] The multiple terminals 111a, 111b, and 111c are power receiving terminals for receiving power supplied from the battery 20 via the substrate 150. In this embodiment, since the motor 110 is a three-phase motor, the motor 110 has three terminals 111a, 111b, and 111c for receiving three-phase power. The three terminals 111a, 111b, and 111c each protrude in a direction parallel to the rotation axis of the motor 110. The three terminals 111a, 111b, and 111c have the same configuration.

[0057] The three terminals 111a, 111b, and 111c are each inserted into a through hole provided in the substrate 150. Specifically, as shown in Fig. 3, the substrate 150 is provided with three through holes 159a, 159b, and 159c. The three through holes 159a, 159b, and 159c each penetrate from the first main surface 150a to the second main surface 150b of the substrate 150. Connectors 250a, 250b, and 250c are provided so as to correspond one-to-one to the through holes 159a, 159b, and 159c.

[0058] The multiple connectors 250a, 250b, and 250c are female connectors provided on the first main surface 150a of the substrate 150. The multiple connectors 250a, 250b, and 250c have insertion openings provided at positions that overlap the corresponding through holes 159a, 159b, and 159c in a plan view. Unless otherwise specified, "plan view" refers to the first main surface 150a of the substrate 150 viewed from the front.

[0059] 4 and 5, connector 250b has an insertion opening 255b. Terminal 111b corresponding to connector 250b is connected to connector 250b by being inserted into insertion opening 255b from the second main surface 150b side of substrate 150 through through hole 159b. Connector 250c has an insertion opening 255c. Terminal 111c corresponding to connector 250c is connected to connector 250c by being inserted into insertion opening 255c from the second main surface 150b side of substrate 150 through through hole 159c.

[0060] 4 and 5, the connector 250a is not shown in order to make it easier to understand the positional relationship between the terminal 111a and the through-hole 159a. Similarly, the connector 250a also has an insertion opening 255a as shown in FIG.

[0061] The connectors 250a, 250b, and 250c have the same configuration. The following description will be directed to the connector 250a as a representative, with reference to FIGS.

[0062] As shown in FIG. 6, connector 250a includes main body 251a, holding portions 252a and 252b, elastic portions 253a, 253b, 253c, and 253d, and fixing portions 254a, 254b, 254c, and 254d. Connector 250a is formed using a metal material such as copper or aluminum. Connector 250a may be integrally formed or may be formed by combining multiple components. In this embodiment, connector 250a is entirely made of a conductive metal member, but an insulating resin or the like may be provided to cover at least a portion of connector 250a.

[0063] The main body 251a is a frame having a rectangular shape in a plan view. The space surrounded by the main body 251a is the insertion opening 255a.

[0064] The holding portions 252a and 252b are portions that hold the terminal 111a inserted into the insertion opening 255a. The holding portions 252a and 252b are portions that extend downward and toward each other from the central upper end portions of two side walls that correspond to the long sides of the main body 251a in a plan view. When the terminal 111a is not inserted, the distance between the closest portions of the holding portions 252a and 252b is less than the thickness of the terminal 111a. Both the holding portions 252a and 252b are elastically deformable. When the terminal 111a is inserted, the holding portions 252a and 252b elastically deform, and the elastic force holds the terminal 111a sandwiched between the holding portions 252a and 252b. When the holding portions 252a and 252b come into contact with the terminal 111a, the connector 250a and the terminal 111a are electrically connected. The means by which the terminals 111a are held by the holding portions 252a and 252b is not particularly limited, and the connector 250a may have one holding portion that holds the terminals 111a.

[0065] Each of the elastic portions 253a, 253b, 253c, and 253d is elastically deformable. When at least one of the elastic portions 253a, 253b, 253c, and 253d elastically deforms, the holding portions 252a and 252b are movable in the radial direction of the motor 110 (the short-side direction of the connector 250a). The elastic portions 253a, 253b, 253c, and 253d are provided at the lower part of each of two side walls that correspond to the long sides of the main body 251a in a plan view. The elastic portions 253a, 253b, 253c, and 253d are each a leaf spring having a curved shape with a predetermined width.

[0066] For example, if the elastic portion 253a is considered to start near the center of the bottom of the side wall corresponding to the long side of the main body 251a in a plan view and end at the fixed portion 254a, it has a shape that protrudes from the start point toward the fixed portion 254a, then travels back and forth to reach the center of the side wall in the vertical direction, and then reaches the fixed portion 254a. When the side wall on which the elastic portion 253a is provided is viewed in plan, the elastic portion 253a does not overlap the holding portion 252b, but the holding portion 252b overlaps the side wall. The holding portion 252b and the elastic portion 253a are arranged so that they do not come into contact with each other even when elastically deformed. The elastic portions 253b, 253c, and 253d also have the same shape as the elastic portion 253a. The shapes of the elastic portions 253a, 253b, 253c, and 253d are not particularly limited. Furthermore, the number of elastic portions provided in the connector 250a may be only one or only two, and is not particularly limited.

[0067] The fixing portions 254a, 254b, 254c, and 254d are portions that fix the connector 250a to the substrate 150. The fixing portions 254a, 254b, 254c, and 254d are provided at the four corners of the connector 250a in a plan view of the substrate 150, and are provided to correspond to the four corners of the through-hole 159a of the substrate 150. The fixing portions 254a, 254b, 254c, and 254d are all electrically connected to metal wiring provided on the substrate 150. For example, the fixing portions 254a, 254b, 254c, and 254d are fixed to and electrically connected to the metal wiring provided on the substrate 150 using a conductive member such as solder. Note that the method of fixing and electrically connecting the fixing portions 254a, 254b, 254c, and 254d is not particularly limited. Furthermore, the number of fixing portions provided in the connector 250a may be only one or only two, and is not particularly limited.

[0068] As described above, in the motor unit 100 according to this embodiment, the connectors 250a, 250b, and 250c are each directly attached to the circuit board 150. Because a harness is not used for the electrical connection between the stator 111 of the motor 110 and the circuit board 150, loss due to heat generation in the harness can be suppressed. This makes it possible to realize a motor unit 100 with high motor efficiency.

[0069] Furthermore, when a connector with a harness is used, the position of the connector is not fixed, so the terminals 111a, 111b, and 111c of the motor 110 must be connected to the connector one by one. In contrast, in the motor unit 100 according to this embodiment, the connectors 250a, 250b, and 250c are fixed to the circuit board 150. Therefore, by moving the motor 110 or the circuit board 150 in a direction parallel to the rotation axis P1 of the motor 110, the terminals 111a, 111b, and 111c of the motor 110 can be easily connected to the connectors 250a, 250b, and 250c in a single operation. This allows for a motor unit 100 that is easy to assemble. Furthermore, the weight of the harness can be reduced, so the weight of the motor unit 100 can be reduced.

[0070] 5, the three terminals 111a, 111b, and 111c are arranged side by side along the rotation direction of the motor 110, that is, along an arc C centered on the rotation axis P1 of the motor 110. For example, the three terminals 111a, 111b, and 111c are arranged at equal intervals in this order.

[0071] In FIG. 5, three imaginary straight lines Da, Db, and Dc are indicated by dashed dotted lines. In a plan view of the substrate 150, the straight lines Da, Db, and Dc are lines passing through the centers of the terminals 111a, 111b, and 111c and the rotation axis P1, respectively. The angle between the straight lines Da and Dc is less than 90 degrees. Thus, the terminals 111a, 111b, and 111c are collectively arranged in a partial area of ​​the stator 111. Therefore, the connectors 250a, 250b, and 250c are also collectively arranged in a partial area of ​​the first main surface 150a of the substrate 150. This allows the wiring electrically connected to the connectors 250a, 250b, and 250c to be arranged close to each other, making it easier to design the wiring layout. Furthermore, a wider area can be secured for arranging electronic components other than the wiring, increasing the degree of freedom in arranging the electronic components. Alternatively, the area of ​​the substrate 150 can be reduced, and the motor unit 100 can be made smaller and lighter.

[0072] The terminals 111a, 111b, and 111c provided on the stator 111 are fixed by molding with resin or the like. Therefore, if misalignment occurs between the terminals 111a, 111b, and 111c and the connectors 250a, 250b, and 250c, stress may be applied to the connection portions (soldered portions) of the connectors 250a, 250b, and 250c, causing them to come off. Misalignment may occur due to manufacturing errors in the stator 111 or the substrate 150, or during installation of the motor 110.

[0073] In contrast, in motor unit 100 according to the present embodiment, circuit board 150 and connectors 250a, 250b, and 250c are provided with a structure that allows for misalignment. Specifically, the structure that allows for misalignment is through-holes 159a, 159b, and 159c provided in circuit board 150, and elastic portions 253a, 253b, 253c, and 253d of connectors 250a, 250b, and 250c, respectively. Below, terminal 111a, through-hole 159a, and connector 250a will be described as representative examples.

[0074] First, the specific configuration of the terminal 111a will be described. The terminal 111a is a plate-shaped terminal whose thickness direction coincides with the radial direction of the motor 110. The terminal 111a has a tapered shape in both the thickness and width directions at the tip end in the protruding direction. This makes it easy to insert the terminal 111a between the holding portions 252a and 252b of the connector 250a. The thickness direction of the terminal 111a is the direction parallel to the double-headed arrow representing the thickness B2 shown in FIG. 7. The width direction of the terminal 111a is the direction parallel to the double-headed arrow representing the width B1 shown in FIG. The radial direction of the motor 110 is the direction parallel to the line Da (lines Db and Dc, respectively, for the terminals 111b and 111c) passing through the rotation axis P1 shown in FIG. 5.

[0075] The through hole 159a has a rectangular shape in a plan view. As shown in FIG. 5, in a plan view, the short side of the through hole 159a coincides with the radial direction (straight line Da) of the motor 110. The long side of the through hole 159a coincides with the tangent direction of the arc C at the intersection of the straight line Da and the arc C. The width A1 of the through hole 159a (i.e., the length in the longitudinal direction) is longer than the width B1 of the terminal 111a. For example, the width A1 is in the range of 1.01 to 3 times the width B1. Therefore, in a plan view, the terminal 111a does not contact the inner wall surface of at least one of both ends of the through hole 159a in the longitudinal direction. That is, a gap exists between the terminal 111a and the through hole 159a in the longitudinal direction.

[0076] Furthermore, the length A2 of the through hole 159a in the short-side direction is longer than the length B2 of the terminal 111a in the short-side direction. For example, the length A2 is in the range of 1.01 to 10 times the length B2. Therefore, in a plan view, the terminal 111a does not contact the inner wall surface of at least one of the two ends of the through hole 159a in the short-side direction. In other words, a gap exists between the terminal 111a and the through hole 159a in the short-side direction. In this way, the through hole 159a is formed larger than the terminal 111a in a plan view. Therefore, even if the terminal 111a is misaligned, the misalignment can be absorbed by the gap between the through hole 159a and the terminal 111a.

[0077] For example, if the position of the terminal 111a shifts along the rotation direction (arc C) of the motor 110, the terminal 111a can move within the through-hole 159a. Furthermore, since the terminal 111a is clamped in the short direction by the holding portions 252a and 252b, the terminal 111a can move in the long direction. Therefore, even if the position of the terminal 111a shifts along the rotation direction (arc C) of the motor 110, the connection between the connector 250a and the terminal 111a can be maintained. Furthermore, excessive stress is not applied to the four fixing portions 254a, 254b, 254c, and 254d of the connector 250a.

[0078] Furthermore, if the position of the terminal 111a shifts along the radial direction (straight line Da) of the motor 110, the terminal 111a can move within the through-hole 159a. Meanwhile, due to the position shift, the terminal 111a presses one of the holding portions 252a and 252b along the radial direction (straight line Da). As shown in FIG. 6, the connector 250a according to this embodiment has elastic portions 253a, 253b, 253c, and 253d. Therefore, at least one of the elastic portions 253a, 253b, 253c, and 253d elastically deforms in response to the pressing force of the terminal 111a. This allows the holding portions 252a and 252b to move in the radial direction, thereby maintaining the connection between the connector 250a and the terminal 111a. Due to the elastic deformation of at least one of the elastic portions 253a, 253b, 253c, and 253d, excessive stress is not applied to the fixed portions 254a, 254b, 254c, and 254d.

[0079] As described above, with the motor unit 100 according to this embodiment, excessive stress is less likely to be applied to the fixed portions 254a, 254b, 254c, and 254d, and the life of the soldered connections is extended. As a result, a highly reliable motor unit 100 can be realized.

[0080] [summary] The main features of the motor unit 100 and the electric bicycle 1, which is an example of an electric vehicle, explained based on the above embodiment will be described below.

[0081] The motor unit 100 according to the first aspect of the present invention is a motor unit used in an electric vehicle, and includes a substrate 150, a motor 110 having terminals 111a, and a connector 250a directly attached to the substrate 150. The terminals 111a and the connector 250a are connected to each other by being inserted into each other in a direction parallel to the rotation axis of the motor 110.

[0082] In this way, the connector 250a to which the terminal 111a of the motor 110 is connected is attached directly to the board 150. Because no harness is used for the electrical connection between the motor 110 and the board 150, loss due to heat generation in the harness can be suppressed. This makes it possible to realize a motor unit 100 with high motor efficiency. Furthermore, because the weight of the harness can be reduced, the weight of the motor unit 100 can be reduced.

[0083] A motor unit 100 according to a second aspect of the present invention is the motor unit according to the first aspect, and the terminal 111a protrudes in a direction parallel to the rotation axis of the motor 110.

[0084] As a result, the terminal 111a protrudes, which increases the degree of freedom in designing the internal structure of the motor 110 (for example, the arrangement of the coils of the stator 111).

[0085] A motor unit 100 according to a third aspect of the present invention is the motor unit according to the second aspect, wherein the substrate 150 has a first main surface 150a and a second main surface 150b opposite the first main surface 150a. The substrate 150 is provided with a through-hole 159a that penetrates from the first main surface 150a to the second main surface 150b. The connector 250a is a female connector provided on the first main surface 150a and has an insertion opening 255a that is provided at a position that overlaps with the through-hole 159a in a plan view of the first main surface 150a. The terminal 111a is connected to the connector 250a by being inserted into the insertion opening 255a from the second main surface 150b side through the through-hole 159a.

[0086] This allows the terminal 111a to be connected to the connector 250a via the through-hole 159a provided in the substrate 150. The second main surface 150b of the substrate 150 and the motor 110 (stator 111) can be arranged close to each other, thereby realizing a reduction in the size of the motor unit 100.

[0087] A motor unit 100 according to a fourth aspect of the present invention is the motor unit according to the third aspect, in which the terminal 111a is a plate-shaped terminal whose thickness direction coincides with the radial direction of the motor 110. The through hole 159a is a rectangular through hole whose short side direction coincides with the radial direction of the motor 110 in a plan view of the first main surface 150a.

[0088] This makes it possible to prevent through-holes 159a from being unnecessarily large by providing through-holes 159a that match the shape of terminals 111a in a plan view. This allows a larger mounting area for substrate 150, making it possible to mount more electronic components. Alternatively, since electronic components can be mounted near terminals 111a, the area of ​​substrate 150 can be reduced.

[0089] The motor unit 100 according to the fifth aspect of the present invention is the motor unit according to the fourth aspect, and in a plan view of the first main surface 150a, the terminal 111a is not in contact with at least one of the inner wall surfaces of both longitudinal ends of the through hole 159a.

[0090] This provides a gap between terminal 111a and through-hole 159a, allowing for greater flexibility in the positioning of terminal 111a within through-hole 159a. Therefore, even if misalignment occurs, excessive stress can be prevented from being applied to the portion of connector 250a that is fixed to substrate 150. This allows for tolerance of misalignment, improving the reliability of the connection of connector 250a.

[0091] A motor unit 100 according to a sixth aspect of the present invention is the motor unit according to the fourth or fifth aspect, in which the connector 250a has elastically deformable elastic portions 253a, 253b, 253c, and 253d, and holding portions 252a and 252b that hold the terminal 111a inserted into the insertion opening 255a. When at least one of the elastic portions 253a, 253b, 253c, and 253d is elastically deformed, the holding portions 252a and 252b can move in the radial direction of the motor 110.

[0092] As a result, even if misalignment occurs in at least one of the terminals 111a and the connector 250a, when the connector 250a and the terminals 111a are connected, at least one of the elastic portions 253a, 253b, 253c, and 253d can be elastically deformed. This makes it possible to prevent excessive stress from being applied to the portion of the connector 250a that is fixed to the board 150. This makes it possible to tolerate misalignment, thereby improving the reliability of the connection of the connector 250a.

[0093] A motor unit 100 according to a seventh aspect of the present invention is the motor unit according to any one of the first to sixth aspects, in which the motor 110 includes a plurality of terminals 111a, 111b, and 111c, which are arranged side by side in the direction of rotation of the motor 110. The motor unit 100 also includes a plurality of connectors 250a, 250b, and 250c, which are arranged in one-to-one correspondence with the plurality of terminals 111a, 111b, and 111c.

[0094] As a result, when multiple terminals 111a, 111b, and 111c and multiple connectors 250a, 250b, and 250c are provided, misalignment is likely to occur. For this reason, motor unit 100, which has a high effect of suppressing stress on the fixing portions of connectors 250a, 250b, and 250c, is highly useful.

[0095] Furthermore, in the motor unit 100 according to this embodiment, the connectors 250a, 250b, and 250c are fixed to the substrate 150, so that the terminals 111a, 111b, and 111c of the motor 110 can be easily connected to the connectors 250a, 250b, and 250c in a single operation by moving the motor 110 or the substrate 150 in a direction parallel to the rotation axis P1 of the motor 110. This makes it possible to realize a motor unit 100 that is easy to assemble.

[0096] An electric bicycle 1, which is an electric vehicle according to the eighth aspect of the present invention, comprises a motor unit 100 according to any one of the first to seventh aspects, a rear wheel (wheel) 13 to which the rotational force of the motor 110 is transmitted, and a frame 11 that supports the motor unit 100 and the rear wheel 13.

[0097] This makes it possible to realize an electric bicycle 1 equipped with a motor unit 100 with high motor efficiency.

[0098] (others) The motor unit and the electric vehicle according to the present invention have been described above based on the above-mentioned embodiment, but the present invention is not limited to the above-mentioned embodiment.

[0099] For example, in the electric bicycle 1, the rotational force of the motor 110 is transmitted to the rear wheel 13, but this is not limited to this. The rotational force of the motor 110 may be transmitted to the front wheel 12. Alternatively, the rotational force of the motor 110 may be transmitted to both the front wheel 12 and the rear wheel 13.

[0100] Furthermore, for example, electric vehicles are not limited to two-wheeled bicycles. They may be tricycles with two front wheels and two rear wheels. Alternatively, electric vehicles may be bicycles with four or more wheels. Furthermore, electric vehicles may be specific small motorized bicycles such as electric kick scooters.

[0101] Furthermore, for example, when the connector 250a is provided on the first main surface 150a, the terminal 111a may be inserted into the connector 250a from the first main surface 150a side. In this case, the stator 111 may be provided on the first main surface 150a side. Furthermore, the female connector 250a may be provided on the second main surface 150b of the substrate 150, and the substrate 150 may not be provided with the through-hole 159a. Furthermore, for example, the connector may be a male connector, and the terminal of the stator 111 may be a female terminal. For example, the male connector may be attached to the second main surface 150b side of the substrate 150 and may be a terminal that protrudes toward the stator 111. Alternatively, the male connector may be attached to the first main surface 150a side of the substrate 150, and a portion of the male connector may protrude toward the second main surface 150b through the through-hole 159a.

[0102] Furthermore, for example, the shapes of the terminal 111a and the connector 250a are not particularly limited. For example, the terminal 111a may be a cylindrical or prismatic terminal, and the connector 250a may be a cylindrical or rectangular tubular connector. The same applies to the terminals 111b and 111c and the connectors 250b and 250c. Furthermore, at least two of the terminals 111a, 111b, and 111c may have different configurations. The same applies to the connectors 250a, 250b, and 250c. Furthermore, for example, the multiple terminals 111a, 111b, and 111c may be arranged in a straight line.

[0103] The number of connectors provided in the motor unit 100 may be one or two, or may be four or more. The number of terminals provided in the stator 111 may be one or two, or may be four or more. There is a one-to-one correspondence between the connectors and the terminals, but multiple terminals may be connected to one connector.

[0104] In addition, the present invention also includes forms obtained by applying various modifications to each embodiment that a person skilled in the art would think of, and forms realized by arbitrarily combining the components and functions of each embodiment within the scope of the present invention. [Explanation of symbols]

[0105] 1. Electric bicycles (electric vehicles) 11 frames 12 Front wheels 13 Rear wheel (wheel) 16a crankshaft 100 Motor unit 110 Motor 111a, 111b, 111c terminals 113 Motor shaft 150 boards 159a, 159b, 159c through holes 160 cases 170 Control circuit 250a, 250b, 250c connectors 252a, 252b holding part 253a, 253b, 253c, 253d Elastic part

Claims

1. A motor unit for use in an electric vehicle, A substrate; a motor having terminals; a connector attached directly to the substrate; The terminal and the connector are connected to each other by being inserted into the other in a direction parallel to the rotation shaft of the motor. Motor unit.

2. The terminals protrude in a direction parallel to the rotation shaft of the motor. The motor unit according to claim 1 .

3. the substrate has a first major surface and a second major surface opposite the first major surface; the substrate is provided with a through hole penetrating from the first main surface to the second main surface, the connector is a female connector provided on the first main surface and has an insertion opening provided at a position overlapping the through hole in a plan view of the first main surface, The terminal is connected to the connector by being inserted into the insertion opening through the through hole from the second main surface side. The motor unit according to claim 2 .

4. the terminal is a plate-shaped terminal whose thickness direction coincides with the radial direction of the motor, The through hole is a rectangular through hole whose short side direction coincides with the radial direction in a plan view of the first main surface. The motor unit according to claim 3 .

5. When viewed from above on the first main surface, the terminal is not in contact with an inner wall surface of at least one of both longitudinal end portions of the through hole. The motor unit according to claim 4.

6. the connector has an elastic portion that is elastically deformable and a holding portion that holds the terminal inserted into the insertion opening, When the elastic portion is elastically deformed, the holding portion is movable in the radial direction.

6. The motor unit according to claim 4 or 5.

7. the motor includes a plurality of the terminals; The plurality of terminals are arranged side by side along the rotation direction of the motor, the motor unit includes a plurality of the connectors, The plurality of connectors are provided in one-to-one correspondence with the plurality of terminals. The motor unit according to any one of claims 1 to 5.

8. A motor unit according to any one of claims 1 to 5; a wheel to which the rotational force of the motor is transmitted; a frame supporting the motor unit and the wheels, Electric vehicle.

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