WO2020067269A1

WO2020067269A1 - Electric vehicle

Info

Publication number: WO2020067269A1
Application number: PCT/JP2019/037819
Authority: WO
Inventors: 梶原詠介; 沼崎芳美; 石川秀男; 藤久保誠; 廣瀬雄大; 渥美和弥; 白砂貴盛; 市川広基; 松平直忠
Original assignee: 本田技研工業株式会社
Priority date: 2018-09-27
Filing date: 2019-09-26
Publication date: 2020-04-02
Also published as: CN112770968B; JP7121803B2; CN112770968A; JPWO2020067269A1

Abstract

An electric vehicle (10) is provided with a motor housing part (98c) mounted on a swing arm (18) and housing a motor (20). In this case, the motor (20) has a stator (90), a rotor (92), and a motor case (94) housing therein the stator (90) in a fixed state while housing therein the rotor (92) in a freely rotatable manner. A portion of the motor case (94) opposing the motor housing part (98c) is fixed to the motor housing part (98c).

Description

Electric vehicle

The present invention relates to an electric vehicle in which a motor is arranged on a swing arm pivotally supported by a pivot shaft.

Japanese Patent Application Laid-Open No. 2012-171548 discloses a vehicle body frame, a pivot shaft provided on the vehicle body frame, a swing arm having one end pivotally supported by the pivot shaft, and a rear wheel supported by the other end of the swing arm. An electric vehicle including a motor disposed on the inside of a swing arm and driving a rear wheel is disclosed. In this case, the swing arm includes a swing arm main body that supports the rear wheel, and a swing arm cover that covers the swing arm main body from outside in the vehicle width direction. The motor is housed in an internal space between the swing arm main body and the swing arm cover.

When the motor is accommodated in the swing arm, the stator and the rotor are assembled at a position near the gear case mainly composed of the swing arm, and then the motor cover is covered so as to cover the stator and the rotor from outside in the vehicle width direction. Cover the swing arm. As described above, since the stator and the rotor, which are the individual components of the motor, are directly assembled to the swing arm, there is room for improvement from the viewpoint of improving the production efficiency of the electric vehicle.

Therefore, an object of the present invention is to provide an electric vehicle that can improve production efficiency.

According to an aspect of the present invention, there is provided a vehicle body frame, a pivot shaft provided on the vehicle body frame, a swing arm having one end pivotally supported by the pivot shaft and the other end supporting a rear wheel, and the swing arm. An electric vehicle including a motor for driving the rear wheel, further comprising a motor housing portion provided on the swing arm and housing the motor, wherein the motor includes a stator, a rotor, and the stator. A motor case that accommodates the rotor therein so as to be rotatable therein, and fixes a portion of the motor case facing the motor accommodation portion to the motor accommodation portion.

According to the present invention, since the motor is arranged on the swing arm simply by fixing the motor case in which the stator and the rotor are accommodated in the motor accommodating portion, the production efficiency of the electric vehicle can be improved.

FIG. 2 is a left side view of the electric vehicle according to the embodiment. FIG. 2 is a perspective view of the vicinity of rear wheels of the electric vehicle in FIG. 1 as viewed from the rear left. FIG. 3 is a left side view in a state where a swing arm cover of FIGS. 1 and 2 is removed. FIG. 4 is a left side view of a state where a left rotor support portion of FIG. 3 is removed. FIG. 5 is a sectional view taken along line VV in FIG. 3. FIG. 4 is a right side view showing a swing arm and the like cut away. It is a bottom view around the front end part of a swing arm. It is a left view which showed the reduction gear accommodating part. It is a perspective view of a swing arm including a reduction gear accommodation part, a brake mechanism, and a breather tube. FIG. 14 is a cross-sectional view of the first modified example along line XX in FIG. 3. FIG. 11A is a side view showing a washer of a comparative example, and FIG. 11B is a side view showing a washer of a second modification. 12A and 12B are side views showing the washer of the second modification. It is a perspective view showing the motor side gear of the 3rd modification. 14A and 14B are cross-sectional views of the periphery of a motor-side gear according to a third modification. It is sectional drawing of the periphery of the motor side gear of the 3rd modification.

Hereinafter, preferred embodiments of the electric vehicle according to the present invention will be described with reference to the accompanying drawings.

[1. Schematic configuration of electric vehicle 10 according to present embodiment]
FIG. 1 is a left side view of an electric vehicle 10 according to the present embodiment. In the following description, front and rear, left and right, and up and down directions will be described according to the direction seen by the occupant sitting on the seat 12 of the electric vehicle 10. In the electric vehicle 10, components arranged on a left and right side may be described with a letter "L" for a component on the left and "R" for a component on the right.

The electric vehicle 10 is an electric scooter having a floor portion 14 with a low floor, and runs by rotating and driving the rear wheel 16 with the driving force of a motor 20 built in a swing arm 18 that supports the rear wheel 16. In addition, the electric vehicle 10 according to the present embodiment is not limited to the electric scooter of FIG. 1, and can be applied to various electric saddle-ride type vehicles driven by the motor 20. In the following description, a scooter-type electric vehicle 10 will be described.

The electric vehicle 10 has a vehicle body frame 22 and a vehicle body cover 24 made of synthetic resin that covers the vehicle body frame 22. The vehicle body frame 22 includes a head pipe 26 at a front end, a down pipe 28 extending obliquely rearward and downward from the head pipe 26, a pair of left and right under frame parts 30L and 30R extending rearward from a rear end of the down pipe 28, and an under frame. And

side frame portions

32L and 32R extending obliquely rearward and upward from the rear ends of the portions 30L and 30R. The

side frame portions

32L, 32R include rising

portions

34L, 34R extending diagonally upward and rearward from the pair of left and right underframe portions 30L, 30R, and rear frames 36L extending rearward from the pair of left and right rising

portions

34L, 34R. 36R. The rear ends of the pair of left and right rear frames 36L, 36R are connected by a tail pipe portion 38.

フロント Front forks 40L and 40R are attached to the head pipe 26 so as to be steerable. A handle 44 is attached to the upper portions of the front forks 40L and 40R via a steering stem 42. A front wheel 46 is attached to lower ends of the front forks 40L and 40R. A front fender 48 that covers the front wheel 46 from above is attached to the front forks 40L and 40R.

連結 A connection support portion 50 including a pivot bracket 50a is provided between the under frame portions 30L and 30R and the

side frame portions

32L and 32R. The connection support 50 supports a pivot shaft 54 extending in the left-right direction (vehicle width direction) of the electric vehicle 10. A front end (one end) of the swing arm 18 is supported by the pivot shaft 54. The swing arm 18 extends from the pivot shaft 54 to the left of the rear wheel 16 along the front-rear direction of the electric vehicle 10. The rear end (the other end) of the swing arm 18 supports the rear wheel 16.

The swing arm 18 incorporates the motor 20 so that the motor 20 is disposed on the left side of the rear wheel 16. Therefore, the swing arm 18 is configured as a swing type power unit. A rear cushion 56 is connected between the rear end of the swing arm 18 and the left rear frame 36L. A rear fender 58 that covers the rear wheel 16 from above is attached to the rear frames 36L and 36R. Further, another fender 60 that directly covers the rear wheel 16 from above between the rear fender 58 and the rear wheel 16 and that can swing with the swing arm 18 is attached to the swing arm 18.

The rear frames 36L and 36R support the seat 12 on which the occupant sits from below. A battery 62 of the electric vehicle 10 is disposed in a space between the pair of right and left rising

portions

34L and 34R between the seat 12 and the pivot shaft 54. The battery 62 is supported by a pair of left and right rising

portions

34L, 34R and rear frames 36L, 36R, and a pipe 64 connecting the rising

portions

34L, 34R at the front.

A PCU (power control unit) 66 as an electronic component supported by the left and right rising

portions

34L and 34R is supported at a position in front of the rear wheel 16 and obliquely behind the battery 62. The PCU 66 includes an inverter and the like, and converts, for example, DC power supplied from the battery 62 to AC power, and supplies the converted AC power to the motor 20. When the motor 20 is regenerated, the PCU 66 converts the AC power generated by the motor 20 into DC power and charges the battery 62. Note that the locations of the battery 62 and the PCU 66 shown in FIG. 1 are merely examples, and may be located at other locations in the electric vehicle 10. For example, the battery 62 may be arranged in a space between the pair of left and right underframe portions 30L and 30R.

The vehicle body cover 24 is a cover that covers the vehicle body frame 22 and the like, and includes a front cover 68, a handle cover 70, a leg shield 72, floor side covers 74L and 74R, a seat lower cover 76, rear side covers 78L and 78R, and the like. The front cover 68 covers the front end of the body frame 22 such as the head pipe 26 from the front. The handle cover 70 covers the left and right central portions of the handle 44 above the front cover 68. The leg shield 72 is connected to the front cover 68 and covers the head pipe 26 and the down pipe 28 from behind. The seat lower cover 76 covers the space below the seat 12 from the front.

The pair of left and right floor side covers 74L and 74R are connected to the leg shield 72 and the seat lower cover 76, and cover the pair of left and right underframe portions 30L and 30R from both left and right sides. The rear side covers 78L and 78R are connected to the rear edge of the seat lower cover 76, and cover the PCU 66 and the like from both left and right sides.

メイン A main stand 80 is provided beside the swing arm 18. In this case, a shaft 82 of the main stand 80 is provided below the swing arm 18, and the main stand 80 is moved so that a part of the main stand 80 is housed in a recess 84 in which the left side of the swing arm 18 is recessed. Will be arranged. In addition, a side stand 86 is disposed near the left rising portion 34L.

[2. Characteristic configuration of the present embodiment]
Next, characteristic configurations (first to fourth configurations) of the electric vehicle 10 according to the present embodiment will be described with reference to FIGS.

<2.1 First configuration>
The first configuration is that the motor 20 is configured as an assembly (unit) in which a stator 90 and a rotor 92 as a driving unit of the motor 20 are incorporated in a motor case 94, and the motor 20 is housed in the swing arm 18. , Constituting a swing type power unit. In other words, simply mounting the completed motor 20 in which the stator 90 and the rotor 92 are housed and the motor shaft 96 is exposed from the motor case 94 in the swing arm 18, attaches the motor 20 to the swing arm 18. The work is completed. Here, the configuration of the swing arm 18 that houses the motor 20 will be described in more detail.

The swing arm 18 has a swing arm body 98. The swing arm body 98 is a hollow member, and has one end 98a extending in the vehicle width direction in a space near the pivot shaft 54 in front of the rear wheel 16, and a connection extending rearward from the left side of the one end 98a. A portion 98b, a motor accommodating portion 98c connected to the connecting portion 98b and arranged on the left side of the rear wheel 16, and another end 98d provided behind the motor accommodating portion 98c.

一端 One end 98a of the swing arm body 98 constitutes the front end of the swing arm 18 and is supported by the pivot shaft 54. As described above, the pivot shaft 54 is supported by the vehicle body frame 22 via the connection support portion 50. As shown in FIGS. 1, 2, 6, and 7, the connection supporting portion 50 extends in the vehicle width direction and connects the pair of left and right rising

portions

34L and 34R, and extends rearward from the pipe 50b. And four pivot brackets 50a that support the pivot shaft 54. Two protrusions 98 e extend forward from both left and right sides of one end 98 a of the swing arm body 98 toward the pivot shaft 54. The two protrusions 98e are supported by the pivot shaft 54 via two bearings 100 provided at both ends of the pivot shaft 54 in the vehicle width direction.

The connecting portion 98b of the swing arm body 98 gradually expands from the front to the rear as viewed from the side in FIGS. 1, 3, and 4. The motor housing 98 c and the other end 98 d of the swing arm main body 98 constitute a rear end of the swing arm 18. The motor accommodating portion 98c is formed in a substantially circular shape in a side view in FIGS. 1, 3 and 4, and is formed so as to be recessed inward in the vehicle width direction in a sectional view in FIG. The rear cushion 56 is connected to the other end 98d of the swing arm body 98.

において In the swing arm body 98, the rear part of the connecting part 98b and the motor housing part 98c are open to the left. This opening is opened to a size that can receive the motor 20 and is covered with the swing arm cover 102 from the left. The swing arm cover 102 is attached to the swing arm body 98 by a plurality of bolts 104. 3 to 5 show a state in which the swing arm cover 102 is removed from the swing arm body 98.

The motor 20 accommodated in the motor accommodating portion 98c is, for example, a three-phase AC motor, and includes a stator 90, a rotor 92, and a motor case 94 accommodating the stator 90 and the rotor 92 therein. The motor case 94 is an outer box of the motor case 94, and serves as a stator support portion 94a as a cylindrical housing extending in the vehicle width direction and a rotor cover for closing two openings at both ends in the vehicle width direction of the stator support portion 94a. And left and right

rotor support portions

94L and 94R.

The stator 90 has a cylindrical stator core 90a made of a laminated steel plate. A plurality of slots 90b are formed in the stator core 90a at predetermined angular intervals in the circumferential direction of the motor 20. A coil 90c is wound around the plurality of slots 90b. The stator support portion 94a is a stator holder that supports the outer peripheral surface of the stator core 90a, that is, the radial outer surface of the motor 20 in the stator 90 in a fixed state. Thereby, the mechanical strength of the stator core 90a made of the laminated steel sheet is reinforced. The stator core 90a is fixed to the stator support 94a by shrink fitting, for example.

ロータ A rotor 92 is disposed radially inward of the stator 90. The rotor 92 has a cylindrical rotor core 92a made of a laminated steel plate. A plurality of slots 92b are formed in the rotor core 92a in the circumferential direction of the motor 20 at predetermined angular intervals. Magnets 92c are arranged in the plurality of slots 92b. A motor shaft 96 extends through the center of the rotor core 92a in the vehicle width direction. The motor shaft 96 extends in the vehicle width direction through an opening formed at the center of the two

rotor support portions

94L and 94R. The motor shaft 96 is supported by two

rotor supporting portions

94L and 94R via bearings 106L and 106R provided in the two openings. That is, the rotor 92 is rotatably supported by the two

rotor supporting portions

94L and 94R via the motor shaft 96 and the two bearings 106L and 106R.

左 The left end portion 96L of the motor shaft 96 projects outward (leftward) in the vehicle width direction from the left rotor support portion 94L. In the left rotor support portion 94L, a portion where the left end portion 96L of the motor shaft 96 projects is formed as a concave portion 108 that is recessed inward in the vehicle width direction. The recess 108 is covered by a cover member 110 from the left. Therefore, even if the swing arm cover 102 is removed from the swing arm body 98, the left end portion 96L of the motor shaft 96 is not exposed (see FIGS. 3 and 5).

(4) A rotation angle detection unit 112 for detecting the rotation angles of the rotor 92 and the motor shaft 96 is provided in an internal space formed by the recess 108 and the cover member 110. The rotation angle detector 112 is a resolver, which is a resolver rotor 112a attached to the left end 96L of the motor shaft 96, and a resolver stator 112b fixed to the left rotor support 94L so as to face the resolver rotor 112a. Having. Since the resolver is well known, a detailed description thereof will be omitted.

On the other hand, the right end (tip) 96R of the motor shaft 96 protrudes inward (rightward) in the vehicle width direction from the right rotor support 94R so as to be directed to the motor housing 98c of the swing arm body 98. Therefore, the right rotor support 94R and the right portion of the stator support 94a are opposed to the motor housing 98c. On the right side of the motor housing 98c of the swing arm body 98, a speed reducer housing 116 for housing a speed reducer 114 described later is provided.

The right end 96R of the motor shaft 96 is inserted into the reduction gear housing 116 and is supported by a bearing 118 provided in the reduction gear housing 116. The right end portion 96R of the motor shaft 96 is splined. A motor-side gear 120 (gear) for rotating an axle (output shaft) 16a of the rear wheel 16 is inserted into the splined portion. Further, a washer 122 is interposed between the motor-side gear 120 and the bearing 118 to prevent the motor-side gear 120 from coming off. The washer 122 is desirably a low-pressure press-fitted washer with respect to the motor shaft 96 so that the motor 20 can be exchanged into the motor accommodating portion 98c. Since the washer 122 has a low press fit, the assembling is easy.

The lubricating oil for lubricating the motor-side gear 120 and the like constituting the speed reducer 114 is filled in the speed reducer housing 116. Therefore, an oil seal 121 is provided between the right rotor support portion 94 </ b> R and the motor shaft 96 to prevent leakage of lubricating oil from the reduction gear housing 116 to the motor case 94. An O-ring 123 for preventing leakage of lubricating oil from the reduction gear housing 116 is provided on the rotor support 94R side between the right rotor support 94R and the motor housing 98c. I have.

A plurality of screw holes (first through hole, second through hole) 124 extending in the vehicle width direction are formed at predetermined angular intervals in the circumferential direction of the motor 20 in the two

rotor support portions

94L, 94R and the stator support portion 94a. Have been. A plurality of

bolts

126 and 128 are screwed into these screw holes 124. As shown in FIGS. 3 to 5, in this embodiment, nine screw holes 124 are formed.

ボルト A bolt 126 having a short length is screwed into the three screw holes 124. The short bolt 126 is used for fixing the rotor supports 94L and 94R to the stator support 94a. As shown in FIG. 5, the short bolt 126 is inserted into the screw hole 124 from the left side, thereby fastening and fixing the rotor support 94L and the stator support 94a to the rotor support 94R.

On the other hand, long bolts (fixing means) 128 are screwed into the other six screw holes 124. The long bolt 128 is used for fixing the motor case 94 including the two rotor supports 94L and 94R and the stator support 94a to the motor housing 98c. That is, the long bolt 128 is inserted into the screw hole 124 from the left side, and screwed into the bolt hole 130 provided in the motor housing 98c, so that the rotor support 94L, the stator support 94a, and the rotor support The 94R is fastened and fixed to the motor housing 98c.

The number and position of the screw holes 124 and the types and numbers of the

bolts

126 and 128 to be screwed into the respective screw holes 124 are arbitrary, and the design may be changed according to the specifications of the swing arm 18 and the motor 20 and the like. Of course it is good.

In the first configuration, when the electric vehicle 10 is manufactured, the motor 20 is attached to the motor housing 98c of the swing arm body 98. The motor 20 includes a motor case 94 in which the stator 90 and the rotor 92 are housed in a motor case 94, and a right end portion 96R of the motor shaft 96 protrudes from the right rotor support portion 94R. To be served. At this time, the bolt 126 having a short length fixes the

rotor support portions

94L and 94R and the stator support portion 94a in a state of permanent fastening, while the long bolt 128 may be temporarily fastened.

In this case, first, the right end portion 96R of the motor shaft 96 is inserted into the reduction gear accommodating portion 116 and is supported by the bearing 118. At this time, the right end portion 96R of the motor 20 may be supported by the bearing 118 in a state where the motor side gear 120 and the washer 122 are fitted into the splined portion on the right end portion 96R side of the motor shaft 96. Next, after positioning the six screw holes 124 where the long bolts 128 are temporarily fastened and the six bolt holes 130 on the motor housing 98c side, the long bolts 128 are screwed into the screw holes 124 and the bolt holes 130. By doing so, the motor case 94 is fixed to the motor housing 98c. As a result, the motor 20 is housed in the motor housing 98c, and the work of attaching the motor 20 to the swing arm 18 is completed.

<2.2 Second Configuration>
The second configuration is a configuration for efficiently cooling the motor 20 by exposing a part of the motor 20 housed in the motor housing portion 98c to the outside.

As shown in FIGS. 1 and 2, the swing arm cover 102 has an exposed portion 132 as an opening for exposing a part of the motor case 94 to the outside. Specifically, in the side view of FIG. 1, the exposed portion 132 is directed from the front to the rear at a position corresponding to the motor housing portion 98c of the swing arm cover 102 so as to expose the rear portion of the motor case 94 to the outside. An opening formed in an arc shape. Further, as shown in FIG. 2, the exposed portion 132 is opened so as to have a constant width in the vehicle width direction, and exposes the motor case 94 to the outside in the vehicle width direction. Moreover, the arc-shaped exposed portion 132 becomes wider in the vertical direction as going from the front to the rear, and the exposed area gradually increases.

Therefore, the swing arm cover 102 has a circular portion 102a that covers the central portion of the motor case 94, that is, the motor shaft 96 and the rotation angle detector 112 (see FIG. 5) from the left side when viewed from the side in FIG. As shown in FIGS. 1 and 2, the circular portion 102a and the rear end portion 102b of the swing arm cover 102 are connected by a connecting portion 102c extending in the front-rear direction. Further, as shown in FIG. 4, the exposed portion 132 is provided so as to correspond to the slot 90b around which the coil 90c is wound. Further, as shown in FIGS. 1, 2 and 4, the exposed portion 132 exposes a part of the motor case 94 to the outside so that the plurality of

bolts

126 and 128 are covered by the swing arm cover 102. .

、 As described above, the motor 20 is a three-phase AC motor. As described later, the motor 20 is driven to rotate by supplying AC power to the coil 90c from the PCU 66 via the power supply line 134 as a three-phase line. In this case, the power supply line 134 is drawn forward from the motor 20. Therefore, the swing arm cover 102 and the swing arm body 98 cover the power supply line 134 from the front and side.

<2.3 Third Configuration>
The third configuration relates to the routing of the power supply line 134 from the motor 20 and the routing of the communication line 136 from the rotation angle detection unit 112.

As shown in FIGS. 6 and 7, a through hole 138 that opens forward is formed at one end 98 a of the swing arm main body 98 at a location in front of the rear wheel 16. The through hole 138 is formed at one end 98 a of the swing arm body 98 above the pivot shaft 54 and at a location between the two bearings 100.

The power supply line 134 is a rigid three-phase wire harness as shown in FIGS. 3, 4, 6, and 7, and is routed inside the swing arm 18 along the internal shape of the swing arm 18. Have been. That is, the power supply line 134 extends forward from the motor 20 inside the swing arm 18, bends inward in the vehicle width direction at one end 98 a of the swing arm body 98, and extends forward from the through hole 138 to the front of the swing arm 18. I have. In this case, the power supply line 134 extends forward of the swing arm 18 through the through hole 138 between the two bearings 100 above the pivot shaft 54. The power supply line 134 drawn out from the through hole 138 is routed above the pivot shaft 54 and connected to the PCU 66 disposed diagonally below and behind the battery 62. Therefore, the PCU 66 and the motor 20 exchange AC power via the power supply line 134.

On the other hand, a communication line 136 is drawn from the rotation angle detection unit 112. The communication line 136 is a harness having lower rigidity than the power supply line 134. Therefore, the communication line 136 is easier to route than the power supply line 134, and extends forward from the rotation angle detection unit 112 in the swing arm 18 so as to crawl along the power supply line 134. It is bent inward in the vehicle width direction at the portion 98a, and extends forward of the swing arm 18 from the through hole 138. Therefore, the communication line 136 also extends forward of the swing arm 18 through the through hole 138 between the two bearings 100 above the pivot shaft 54. Then, the communication line 136 drawn from the through hole 138 is routed above the pivot shaft 54 and connected to the PCU 66. Therefore, the PCU 66 and the rotation angle detection unit 112 can transmit and receive the detection results of the rotation angles of the rotor 92 and the motor shaft 96 via the communication line 136.

Further, inside the swing arm 18, specifically, at the connecting portion 98 b of the swing arm main body 98, the power supply line 134 and the communication line 136 are bound by a binding member 140 such as a grommet, and the stay 142 connects the inside of the connecting portion 98 b. (See FIGS. 6 and 7).

In addition, since the through hole 138 is formed so as to open forward, there is a possibility that liquid such as water may enter the swing arm 18 from the front through the through hole 138 when the electric vehicle 10 travels. Therefore, a hole 144 for draining water is formed at the bottom of the swing arm body 98. FIGS. 6 and 7 show, as an example, a case where the hole 144 is formed at a position near the through hole 138 on the bottom of the swing arm body 98.

Further, inside the swing arm body 98, the strength of the swing arm body 98 is provided between the through hole 138 and the motor accommodating portion 98c, specifically, at a position from the rear portion of the connecting portion 98b to the motor accommodating portion 98c. A plurality of ribs 146 for reinforcement are provided.

<2.4 Fourth configuration>
In the fourth configuration, when the lubricating oil used for the speed reducer 114 evaporates due to an increase in the pressure (internal pressure) in the speed reducer housing 116 due to a rise in the temperature inside the speed reducer housing 116. And a breather tube 148 for discharging gas containing mist-like lubricating oil to the outside to reduce the internal pressure. Here, the configuration around the reduction gear housing 116 will be described.

As shown in FIGS. 5, 8 and 9, the swing arm 18 is further provided with a speed reducer accommodating portion 116 that is attached to the inside of the swing arm body 98 in the vehicle width direction and houses the speed reducer 114. A brake mechanism 150 is provided inside the reduction gear housing 116 in the vehicle width direction and inside the wheel 16 b of the rear wheel 16. Therefore, around the rear wheel 16, the motor 20, the speed reducer 114, and the brake mechanism 150 are sequentially arranged from the left side to the right side in the vehicle width direction.

ギヤ A gear case cover 154 is fixed to the right side of the motor housing portion 98c of the swing arm body 98 by bolts 152. The internal space formed by the motor housing 98c and the gear case cover 154 is configured as the reduction gear housing 116.

The speed reducer 114 is mounted on the motor shaft 96, an intermediate shaft 156 disposed behind the motor shaft 96 and extending in the vehicle width direction, mounted on the intermediate shaft 156, and meshed with the motor gear 120. And an output gear 162 mounted on the axle 16a of the rear wheel 16 disposed behind the intermediate shaft 156 and meshing with a gear 160 formed on the left side of the intermediate shaft 156 in the vehicle width direction. And

右 The right end of the intermediate shaft 156 is supported by a bearing 164R disposed on the gear case cover 154. The left end of the intermediate shaft 156 is supported by a bearing 164L disposed on the right side of the motor housing 98c. The left end of the axle 16a is supported by a bearing 166L disposed on the right side of the motor housing 98c. The right end of the axle 16a is exposed to the outside through the gear case cover 154 and is connected to the wheel 16b of the rear wheel 16. The right end side of the axle 16a is supported by a bearing 166R arranged on the gear case cover 154.

Therefore, when the motor 20 is driven to rotate the motor shaft 96, the driving force of the motor 20 is transmitted to the axle 16 a via the motor-side gear 120, the intermediate gear 158, the intermediate shaft 156, the gear 160 and the output gear 162. The rear wheel 16 connected to the axle 16a can be rotated. In this case, the speed reducer 114 reduces the rotation speed of the motor shaft 96 by the intermediate gear 158, and drives the axle 16a and the rear wheel 16 to rotate.

The brake mechanism 150 is a drum brake, and includes a drum 150a provided inside the wheel 16b, two shoes 150b arranged on both sides of the axle 16a, and a lining arranged on the drum 150a side of the shoe 150b. 150c. In this case, when the two shoes 150b are separated from each other against the tensile force of the spring member 150d inserted between the two shoes 150b, the lining 150c of the two shoes 150b presses the drum 150a, respectively. The rotation of the wheel 16b (rear wheel 16) on which the drum 150a is mounted can be braked. Since the drum brake is well known, a detailed description thereof will be omitted.

In the fourth configuration, the swing arm 18 is provided with a breather tube 148 extending from the reduction gear housing 116 (see FIGS. 2 to 4, 8, and 9). The breather tube 148 is provided above the reduction gear housing 116. Therefore, the breather tube 148 is disposed between the motor 20 and the rear wheel 16 as in the case of the reduction gear housing 116.

One end 148a, which is the inlet of the breather tube 148, is fixed to the gear case cover 154 and communicates with the reduction gear housing 116. The other end 148b, which is the outlet of the breather tube 148, is disposed above the swing arm 18 on a fender 60 that can swing together with the swing arm 18. In this case, the other end 148b of the breather tube 148 is fixed to the fender 60 by inserting the other end 148b of the breather tube 148 into a cylindrical fixing portion 168 provided on the left side surface of the fender 60. Therefore, the breather tube 148 is arranged with one end 148a (entrance) directed downward and the other end 148b (exit) directed upward.

As shown in FIGS. 8 and 9, an upper wall 170 extending in the front-rear direction is formed above the reduction gear housing 116 on the right side of the motor housing 98 c. The breather tube 148 extends upward from the reduction gear housing 116, bends forward along the upper wall 170, bends upward at the front end of the upper wall 170, and extends to the fixing portion 168 of the fender 60. . In this case, the upper wall 170 is inclined such that the other end 148b of the breather tube 148 is higher than the one end 148a. Therefore, in the breather tube 148, the intermediate portion 148c disposed on the upper wall 170 is inclined and disposed on the upper wall 170 so as to gradually increase toward the front. The upper wall 170 is provided with a fixing portion 172 such as a projection for projecting upward to fix the breather tube 148 to the upper wall 170 and the right side of the motor accommodating portion 98c.

A plate member 174 extending vertically and in the front-rear direction is integrally formed on the front side surface of the fender 60. The other end 148b (outlet) of the breather tube 148 is disposed on the left side of the plate member 174. Therefore, the plate member 174 is disposed between the breather tube 148 and the rear wheel 16.

On the other hand, as shown in FIG. 8, one end 148a (entrance) of the breather tube 148 is disposed between the motor shaft 96 and the axle 16a, more specifically, between the intermediate shaft 156 and the axle 16a.

<2.5 Modification>
Next, a modified example of the present embodiment will be described with reference to FIGS. These modifications are all modifications of the first configuration.

In the first modified example shown in FIG. 10, a positioning pin 180 as a knock pin is provided in one of the right rotor support portion 94R and the motor housing portion 98c in the left-right direction, and a positioning hole 182 fitted to the positioning pin 180 is provided in the other. Is provided. FIG. 10 shows an example in which positioning pins 180 are provided in the motor housing 98c and positioning holes 182 are formed in the rotor support 94R. Therefore, in the first modified example, the long bolt 128 (see FIG. 5) and the bolt hole 130 are screwed together with the positioning pin 180 fitted in the positioning hole 182.

Next, a second modification will be described with reference to FIGS. 11A to 12B. In the second modification, the shape of the washer 122 is devised in order to fit the washer 122 into the motor shaft 96 with low pressure.

FIG. 11A shows a washer 184 of a comparative example for the second modification. In the washer 184 of the comparative example, a linear portion 122a substantially perpendicular to the radial direction of the washer 184 is formed on one side of the inner peripheral portion of the washer 184. Accordingly, the washer 184 has an asymmetric shape with respect to the center of the washer 184. Thus, when the right end 96R of the motor shaft 96 is inserted into the washer 184, the washer 184 may be inclined with respect to the axial direction of the motor shaft 96.

FIG. 11B shows the washer 122 of the present embodiment. In an inner peripheral portion of the washer 122, straight portions 122a substantially perpendicular to the radial direction of the washer 122 are formed at two portions facing each other with the center of the washer 122 interposed therebetween. Therefore, the washer 122 has a substantially symmetrical shape with respect to the center of the washer 122. Thereby, the right end 96R of the motor shaft 96 can be inserted into the washer 122 with low pressure while suppressing the washer 122 from being inclined with respect to the axial direction of the motor shaft 96. In FIG. 11B, the inner diameter side of the straight portion 122a may be formed in an arcuate curved portion.

In FIGS. 12A and 12B, a load reducing portion 122b formed of a through hole or a recess is provided near each straight portion 122a in the washer 122. FIG. 12A illustrates a true circular load reducing portion 122b, and FIG. 12B illustrates an oval load reducing portion 122b. By providing the load reducing portion 122b, the load generated when the right end portion 96R of the motor shaft 96 is inserted into the washer 122 is reduced, and the inclination of the washer 122 with respect to the axial direction of the motor shaft 96 is suppressed. can do. 12A and 12B, the inner diameter side of the linear portion 122a may be formed in an arcuate curved portion.

Next, a third modification will be described with reference to FIGS. In the third modification, a method of supplying lubricating oil to the motor-side gear 120 is devised.

As shown in FIGS. 13 and 14A, in the third modification, the lubricating oil passes through the right side surface of the motor-side gear 120, that is, the end surface of the motor-side gear 120 on the side of the washer 122 (the inner side surface in the vehicle width direction). A groove 120a is formed along the radial direction of the motor-side gear 120. FIG. 13 illustrates a case where four grooves 120a are formed in the radial direction at 90 ° intervals on the right side surface of the motor-side gear 120. Thus, the lubricating oil filled in the reduction gear housing 116 is supplied to the inner peripheral side and the outer peripheral side of the motor side gear 120 through the groove 120a, and lubricates the motor side gear 120 uniformly. Note that at least one groove 120a may be formed on the right side surface of the motor-side gear 120.

Further, in the third modification, as shown in FIG. 14B, the motor-side gear 120 is also provided on the left side surface of the motor-side gear 120, that is, the end surface of the motor-side gear 120 on the motor case 94 side (the outer side surface in the vehicle width direction). At least one groove 120a may be formed along the radial direction of the groove 120. As a matter of course, similarly to the case of FIG. 13, even in the case of FIG. 14B, four grooves 120a may be formed on the left side surface of the motor-side gear 120 at 90 ° intervals in the radial direction.

Further, in the third modification, as shown in FIG. 15, a mechanism for positively supplying lubricating oil to the motor-side gear 120 may be provided. Specifically, a supply hole 96a for supplying lubricating oil is provided in the right end portion 96R of the motor shaft 96. In addition, the supply hole 96a and a portion on the inner peripheral surface side of the motor-side gear 120 on the outer peripheral surface of the motor shaft 96 are communicated with each other through the communication hole 96b. Further, an oil passage 186 for supplying lubricating oil to the supply hole 96a from above or outside the reduction gear housing 116 is provided. Accordingly, the lubricating oil supplied to the supply hole 96a via the oil passage 186 flows to the inner peripheral surface side of the motor-side gear 120 via the communication hole 96b. The inner peripheral surface of the motor-side gear 120 and the outer peripheral surface of the motor shaft 96 are splined, but there are slight gaps in these portions. The lubricating oil flows through the groove 120a through these gaps and reaches the outer peripheral surface of the motor-side gear 120. Thereby, the motor side gear 120 can be evenly lubricated.

[3. Effects of the present embodiment]
The effects of the electric vehicle 10 according to the present embodiment described above will be described in the order of the first to fourth configurations.

In the electric vehicle 10 according to the present embodiment, the vehicle body frame 22, a pivot shaft 54 provided on the vehicle body frame 22, a front end (one end) is pivotally supported by the pivot shaft 54, and a rear end (the other end). Are provided with a swing arm 18 that supports the rear wheel 16 and a motor 20 that is disposed on the swing arm 18 and drives the rear wheel 16.

<3.1 Effect of First Configuration>
As a first configuration, the electric vehicle 10 further includes a motor housing 98 c provided on the swing arm 18 and housing the motor 20. The motor 20 includes a stator 90, a rotor 92, and a motor case 94 that houses the stator 90 in a fixed state therein, while rotatably houses the rotor 92 therein. The portion facing the portion 98c is fixed to the motor housing 98c.

Thus, in the first configuration, the motor 20 is arranged on the swing arm 18 only by fixing the motor case 94 in which the stator 90 and the rotor 92 are accommodated to the motor accommodating portion 98c. Can be improved.

Further, a screw hole (first through hole) 124 is formed in the motor case 94 so as to face the motor housing portion 98c. By inserting a bolt 128 into the screw hole 124, the motor case 94 and the motor housing portion 98c in the motor case 94 can be connected. The facing portion is fixed to the motor housing 98c. Thus, the motor case 94 can be easily fixed to the motor housing 98c.

Furthermore, the motor case 94 has

rotor support portions

94L and 94R that rotatably support the rotor 92 and a stator support portion 94a that supports the radial outer surface of the motor 20 in the stator 90. By making the stator support portion 94a and the

rotor support portions

94L and 94R function as a part of the motor case 94, the number of parts of the motor 20 can be reduced.

Further, screw holes (second through holes) 124 are formed in the

rotor support portions

94L and 94R and the stator support portion 94a so as to be directed to the motor accommodating portion 98c, and a part of the rotor support portion 94R and a part of the stator support portion 94a are formed. It is configured as an opposing portion. In this case, by inserting the bolt 128 into the screw hole 124, the facing portion is fixed to the motor housing 98c. Thus, the motor case 94 can be easily fixed to the motor housing 98c while reducing the number of parts of the motor 20.

モータ Further, a motor shaft 96 projecting from the motor case 94 is supported by the rotor 92 such that a right end (tip) 96R is directed to the motor accommodating portion 98c. The right end 96R of the motor shaft 96 is rotatably supported by a bearing 118 provided on the side of the motor housing 98c. As a result, the motor shaft 96 can be favorably supported by the motor housing 98c.

In this case, a spline process is performed on the right end portion 96R side of the motor shaft 96, and a motor-side gear (gear) 120 for driving the axle 16a of the rear wheel 16 is inserted into the spline processed portion. ing. Further, a washer 122 is provided between the motor-side gear 120 and the bearing 118 to prevent the motor from being disengaged. Thus, the motor-side gear 120 can be prevented from coming off the motor shaft 96.

における In the inner peripheral portion of the washer 122, two portions facing each other with the center of the washer 122 interposed therebetween are formed as linear portions 122a orthogonal to the radial direction of the washer 122, respectively. Thereby, two linear portions 122a are provided symmetrically with respect to the center of the washer 122. As a result, when the washer 122 is inserted into the motor shaft 96, it is possible to suppress the washer 122 from being inclined with respect to the axial direction of the motor shaft 96. In addition, since the press-fit load of the washer 122 on the motor shaft 96 is reduced, the load on the worker is reduced, and the washer 122 is press-fitted onto the motor shaft 96 without using equipment such as a press-fit press or a tool such as a hammer. Can be.

In this case, a load reducing portion 122b formed of a through hole or a concave portion may be provided near each straight portion 122a in the washer 122. Accordingly, the rigidity near the linear portion 122a is reduced, and the press-fit load of the washer 122 on the motor shaft 96 can be further reduced.

Further, at least one groove 120a through which lubricating oil passes may be formed in the end face of the motor-side gear 120 on the side of the washer 122 along the radial direction of the motor-side gear 120. Thus, lubricating oil can be supplied to the motor-side gear 120 to facilitate lubrication. Further, occurrence of fretting can be suppressed.

In this case, at least one groove 120 a may be formed on the end surface of the motor-side gear 120 on the motor case 94 side along the radial direction of the motor-side gear 120. Thereby, grooves 120a are formed on both sides of the motor-side gear 120. As a result, erroneous assembly of the motor-side gear 120 with respect to the motor shaft 96 can be prevented, and the motor-side gear 120 can be easily lubricated with the lubricating oil supplied through the grooves 120a provided on the left and right.

The motor shaft 96 is provided with a supply hole 96a through which lubricating oil is supplied, and a communication hole 96b that communicates the supply hole 96a with a portion of the outer peripheral surface of the motor shaft 96 on the inner peripheral surface side of the motor-side gear 120. It may be formed. As a result, the lubricating oil filled in the reduction gear housing portion 116 or the lubricating oil from the outside is positively supplied to the supply hole 96a, and is supplied to the motor-side gear 120 through the communication hole 96b. Can be. As a result, the motor-side gear 120 can be more efficiently and reliably lubricated.

Further, one of the motor case 94 and the motor housing 98c may be provided with a positioning pin 180, and the other may be provided with a positioning hole 182 fitted with the positioning pin 180. This makes it possible to easily and accurately align the screw hole 124 of the motor case 94 with the bolt hole 130 of the motor housing 98c. As a result, the loosening of the long bolt 128 after the motor case 94 is fastened and fixed to the motor housing portion 98c can be suppressed.

<3.2 Effect of Second Configuration>
In the second configuration, the electric vehicle 10 further includes a motor accommodating portion 98c provided on the swing arm 18 and accommodating the motor 20. The motor 20 has a motor case 94 that houses a stator 90 and a rotor 92 that are driving units of the motor 20. The swing arm 18 has a swing arm cover 102 provided with an exposed part 132 for exposing a part of the motor case 94 to the outside.

According to this, in the second configuration, the heat of the motor 20 is radiated to the outside through the exposed portion 132 provided on the swing arm cover 102. As a result, the motor 20 housed in the motor housing 98c of the swing arm 18 can be efficiently cooled.

The electric vehicle 10 further includes a power supply line 134 for supplying power to the motor 20. The swing arm cover 102 covers the power supply line 134. Thus, the design of the electric vehicle 10 can be improved while protecting the power supply line 134.

In this case, the power supply line 134 is disposed in front of the motor 20, and the swing arm cover 102 covers the power supply line 134 from the front. Thus, the power supply line 134 can be protected from stepping stones and the like from the front while the electric vehicle 10 is traveling.

Further, the motor 20 is a three-phase AC motor, and the power supply line 134 may be a three-phase line that supplies power to the AC motor. Thereby, the electric vehicle 10 can be suitably driven.

Furthermore, the exposed part 132 exposes the rear part of the motor case 94 to the outside. Thus, the motor 20 can be cooled while protecting the power supply line 134 from a stepping stone or the like from the front.

露出 The exposed portion 132 exposes the motor case 94 to the outside in the vehicle width direction of the electric vehicle 10. Thereby, the cooling efficiency of the motor 20 can be further improved.

Further, the exposed portion 132 becomes wider toward the rear of the electric vehicle 10. Thereby, the cooling efficiency of the motor 20 can be improved while protecting the inside of the swing arm 18 from stepping stones or the like from the front.

Furthermore, the swing arm cover 102 covers the central part of the motor case 94 in a side view. Thereby, the rotation angle detection unit 112, the motor shaft 96, and the like can be protected.

露出 The exposed portion 132 is formed in an arc shape in a side view. Thereby, the stator 90 constituting the motor 20 can be efficiently cooled.

Further, a driving portion of the motor 20 is constituted by a stator 90 fixed inside the motor case 94 and a rotor 92 rotatably supported inside the motor case 94. Therefore, in the second configuration, the stator 90 and the rotor 92 can be appropriately cooled.

The exposed portion 132 is formed on the stator 90 in a side view, and is provided so as to correspond to the slot 90b around which the coil 90c is wound. Thereby, cooling of stator 90 can be performed more efficiently. That is, the coil 90c is a component that generates the largest amount of heat in the motor 20 because the coil 90c is energized by the power supplied from the power supply line 134. Therefore, by providing the exposed portion 132 corresponding to the coil 90c, the stator 90 can be cooled more efficiently.

(4) Further, the motor 20 is housed in the motor housing 98c by fixing the motor case 94 to the motor housing 98c via a bolt (fixing means) 128. The exposed part 132 exposes a part of the motor case 94 to the outside so that the bolt 128 is covered by the swing arm cover 102. Thus, the motor 20 can be cooled while the design of the electric vehicle 10 is improved by hiding the bolt 128.

<3.3 Effect of Third Configuration>
In the third configuration, the electric vehicle 10 further includes a motor accommodating portion 98 c that is provided on the side of the rear wheel 16 in the swing arm 18 and accommodates the motor 20, and a power supply line 134 that supplies power to the motor 20. In this case, a through hole 138 is formed at the front end (one end 98 a) of the swing arm 18 at a location in front of the rear wheel 16. The power supply line 134 extends forward from the motor 20 in the swing arm 18, bends at one end 98 a in the vehicle width direction of the electric vehicle 10, and extends from the through hole 138 to the outside of the swing arm 18.

Accordingly, the power supply line 134 extends from the motor 20 through the inside of the swing arm 18 to the outside through the through hole 138 formed in the one end 98a. As a result, when the power supply line 134 is provided from inside the swing arm 18 to the outside, the power supply line 134 can be provided more linearly without being bent so much. Further, since the degree of exposure of the power supply line 134 to the outside is reduced, the number of components for protecting the power supply line 134 externally can be reduced and the appearance can be improved. Further, since a space above or below the swing arm 18 is secured, a space for mounting the battery 62 above the pivot shaft 54 can be secured, for example. As a result, the minimum ground clearance of the swing arm 18 can be secured.

には Two bearings 100 are provided at both ends of the pivot shaft 54 in the vehicle width direction. One end 98a is pivotally supported by the pivot shaft 54 via two bearings 100. The through hole 138 is formed at a position between the two bearings 100 at the one end 98 a, and the power supply line 134 extends to the outside of the swing arm 18 through the through hole 138 between the two bearings 100.

As described above, the power supply line 134 is exposed to the outside in the vehicle width direction, not in the vehicle width direction. Thus, when the electric vehicle 10 is tilted at the time of cornering of the electric vehicle 10, contact of the power supply line 134 with the road surface is avoided, so that the bank angle of the electric vehicle 10 can be secured.

Furthermore, the through hole 138 is formed at a position above the pivot shaft 54 at the one end 98a, and the power supply line 134 extends outside the swing arm 18 from above the pivot shaft 54 via the through hole 138. Thereby, the minimum ground clearance of the electric vehicle 10 including the swing arm 18 can be secured.

Further, a rib 146 is provided between the through hole 138 in the swing arm 18 and the motor housing 98c. Thereby, the mechanical strength of the swing arm 18 can be reinforced.

The electric vehicle 10 further includes a rotation angle detection unit 112 that is disposed on the motor 20 and detects a rotation angle of the motor 20, and a communication line 136 extending from the rotation angle detection unit 112. In this case, the communication line 136 extends forward from the rotation angle detection unit 112 in the swing arm 18 so as to crawl along the power supply line 134, bends inward in the vehicle width direction at one

end

98 a, 18 extend outside. Thereby, the bending inside the swing arm 18 together with the power supply line 134 can be reduced, and the appearance can be improved while avoiding exposure to the outside.

The electric vehicle 10 further includes a stay 142 for fixing the power supply line 134 to the swing arm 18 in the swing arm 18. Thus, the power supply line 134 linearly arranged inside the swing arm 18 can be held.

Further, a hole 144 for draining water is formed at the bottom of the swing arm 18. Thus, the liquid that has entered the swing arm 18 through the through hole 138 drops downward through the hole 144. As a result, it is possible to avoid occurrence of a short circuit or the like of the power supply line 134 due to a liquid such as water.

The electric vehicle 10 further includes a battery 62 and a PCU (electronic component) 66 supported by the body frame 22. The power supply line 134 is drawn out of the through-hole 138 and connected to the PCU 66. The PCU 66 supplies the electric power supplied from the battery 62 to the motor 20 via the power supply line 134. Thus, electric power can be supplied from the PCU 66 to the motor 20 to drive the motor 20.

In this case, since the motor 20 is an AC motor, and the power supply line 134 is a three-phase line that supplies power to the AC motor, the electric vehicle 10 can run properly.

<3.4 Effect of Fourth Configuration>
In the fourth configuration, the electric vehicle 10 includes a speed reducer 114 that transmits the driving force of the motor 20 to the rear wheel 16, a speed reducer housing 116 that is provided on the swing arm 18 and houses the speed reducer 114, A breather tube 148 extending from the storage section 116. One end 148 a of the breather tube 148 communicates with the reduction gear housing 116. The other end 148 b of the breather tube 148 is disposed above the swing arm 18 on a fender 60 (a component of the electric vehicle 10) that can swing together with the swing arm 18.

Since the other end 148b of the breather tube 148 is thereby arranged upward, the lubricating oil liquefied in the breather tube 148 returns to the reduction gear housing 116 via the one end 148a of the breather tube 148. As a result, the liquefied lubricating oil is not discharged to the outside, so that the electric vehicle 10 and the like can be prevented from being contaminated.

減速 Further, the reduction gear housing 116 and the breather tube 148 are arranged between the motor 20 and the rear wheel 16. Thereby, the space between the motor 20 and the rear wheel 16 can be effectively utilized.

Furthermore, the breather tube 148 is arranged along the upper wall 170 provided near the speed reducer housing 116 of the swing arm 18. Thus, the breather tube 148 can be cooled by the traveling wind while protecting the breather tube 148 from flying stones or the like while the electric vehicle 10 is traveling. Further, by arranging the breather tube 148 in the upper wall 170, even if the breather tube 148 flaps due to vibration during traveling, it can be prevented from contacting the rear wheel 16.

In this case, the upper wall 170 is inclined so that the other end 148b of the breather tube 148 is higher than the one end 148a. Thus, even when the gas is liquefied into lubricating oil by cooling the breather tube 148, the lubricating oil returns to the reduction gear housing 116 from one end 148a of the breather tube 148. As a result, it is possible to prevent the lubricating oil from being discharged from the other end 148b of the breather tube 148 to the outside.

The upper wall 170 is provided with a fixing portion 172 for fixing the breather tube 148 to the swing arm 18 and the upper wall 170. Thereby, the breather tube 148 can be prevented from being caught in the rear wheel 16.

Furthermore, the breather tube 148 is arranged with the other end 148b, which is the outlet, directed upward. Accordingly, it is possible to reliably prevent the lubricating oil from being discharged from the outlet of the breather tube 148 to the outside.

Furthermore, the breather tube 148 is disposed with the one end 148a, which is the entrance, directed downward. Thus, the lubricating oil liquefied in the breather tube 148 can be reliably returned to the reduction gear housing 116.

他端 The other end 148b, which is the outlet of the breather tube 148, is disposed on the side surface of the fender 60. Thus, the other end 148b of the breather tube 148 can be easily fixed.

In this case, a plate member 174 is disposed between the breather tube 148 and the rear wheel 16. Thus, when the other end 148b of the breather tube 148 comes off the fender 60, the breather tube 148 is prevented from being caught in the rear wheel 16, and the lubricating oil discharged from the outlet adheres to the rear wheel 16. That can be avoided.

Furthermore, the plate member 174 is formed integrally with the fender 60. Thereby, the plate member 174 can be easily provided.

Further, one end 148a, which is an inlet of the breather tube 148, is provided between a motor shaft 96 of the motor 20 and an axle (output shaft) 16a that transmits a driving force from the motor shaft 96 to the rear wheel 16. I have. Thus, when a gas containing mist-like lubricating oil is generated due to an increase in internal pressure due to a rise in temperature inside the reduction gear housing 116, the gas can be efficiently discharged to the outside.

In this case, the inlet of the breather tube 148 is provided between the axle 16a and the intermediate shaft 156 of the speed reducer 114 that transmits the driving force from the motor shaft 96 to the axle 16a. Thereby, the gas containing the mist-like lubricating oil can be more efficiently discharged to the outside.

Although the present invention has been described using the preferred embodiments, the technical scope of the present invention is not limited to the description of the above embodiments. It is apparent to those skilled in the art that various changes or improvements can be made to the above embodiment. It is apparent from the description of the appended claims that embodiments with such changes or improvements can be included in the technical scope of the present invention. Further, the reference numerals in parentheses described in the claims are given according to the reference numerals in the accompanying drawings for easy understanding of the present invention, and the present invention is limited to the elements with the reference numerals. It is not interpreted.

Claims

A vehicle body frame (22), a pivot shaft (54) provided on the vehicle body frame (22), one end of which is pivotally supported by the pivot shaft (54), and the other end of which supports the rear wheel (16). An electric vehicle (10) including a swing arm (18) and a motor (20) disposed on the swing arm (18) and driving the rear wheel (16).
A motor housing (98c) provided on the swing arm (18) for housing the motor (20);
The motor (20) accommodates a stator (90), a rotor (92), and the stator (90) in a fixed state therein, while the motor (20) rotatably accommodates the rotor (92) therein. A case (94),
An electric vehicle (10), wherein a portion of the motor case (94) facing the motor housing (98c) is fixed to the motor housing (98c).
The electric vehicle (10) according to claim 1,
The motor case (94) has a first through-hole (124) directed toward the motor accommodating portion (98c).
The electric vehicle (10), wherein the opposing portion of the motor case (94) is fixed to the motor housing (98c) by inserting a bolt (128) into the first through hole (124).
The electric vehicle (10) according to claim 1 or 2,
The motor case (94) includes a rotor supporting portion (94L, 94R) that rotatably supports the rotor (92) and a stator support that supports a radial side surface of the motor (20) in the stator (90). An electric vehicle (10) having a portion (94a).
The electric vehicle (10) according to claim 3,
The rotor support portions (94L, 94R) and the stator support portion (94a) are formed with a second through hole (124) directed to the motor housing portion (98c).
A part of the rotor support part (94R) and the stator support part (94a) is configured as the opposed part;
The electric vehicle (10), wherein the opposing portion is fixed to the motor housing (98c) by inserting a bolt (128) through the second through hole (124).
The electric vehicle (10) according to any one of claims 1 to 4,
A motor shaft (96) projecting from the motor case (94) is supported by the rotor (92) such that a tip end (96R) faces the motor housing (98c).
The electric vehicle (10), wherein a tip (96R) of the motor shaft (96) is rotatably supported by a bearing (118) provided on the motor housing (98c) side.
The electric vehicle (10) according to claim 5,
The motor shaft (96) is splined on the tip (96R) side,
A gear (120) for driving an axle (16a) of the rear wheel (16) is inserted into the splined portion,
The electric vehicle (10), wherein a washer (122) for retaining is provided between the gear (120) and the bearing (118).
The electric vehicle (10) according to claim 6,
Two portions of the inner peripheral portion of the washer (122) facing each other across the center of the washer (122) are formed as linear portions (122a) orthogonal to the radial direction of the washer (122). , An electric vehicle (10).
The electric vehicle (10) according to claim 7,
The electric vehicle (10), wherein a load reduction section (122b) including a through hole or a recess is provided in the washer (122) near each of the linear sections (122a).
The electric vehicle (10) according to any one of claims 6 to 8,
An electric vehicle (10) in which at least one groove (120a) through which lubricating oil passes is formed along the radial direction of the gear (120) on an end surface of the gear (120) on the side of the washer (122). ).
The electric vehicle (10) according to claim 9,
The electric vehicle (10), wherein at least one groove (120a) is formed in an end surface of the gear (120) on the motor case (94) side along a radial direction of the gear (120).
The electric vehicle (10) according to claim 9 or 10,
The motor shaft (96) has a supply hole (96a) through which the lubricating oil is supplied, and an inner peripheral surface side of the gear (120) on the outer peripheral surface of the supply hole (96a) and the motor shaft (96). And a communication hole (96b) for communicating with the point (1).
The electric vehicle (10) according to any one of claims 1 to 11,
One of the motor case (94) and the motor accommodating portion (98c) is provided with a positioning pin (180), and the other is provided with a positioning hole (182) to be fitted with the positioning pin (180). , An electric vehicle (10).