Electric vehicle

Abstract

To provide an electric vehicle where a motor is supported by a suspension which has a technique suppressing fluctuation of a power cable connecting the motor with an inverter.SOLUTION: An electric vehicle comprises: an axle extending in a vehicle width direction; a motor which is connected with the axle and drives the axle; a suspension which support the axle and the motor; an inverter fixed to a chassis which supplies the motor with electric power; a power cable which connects the inverter with the motor; and a support bracket which supports the power cable. The suspension fluctuates the axle and the motor along a circular arc when viewed along the vehicle width direction. The support bracket fluctuates with the motor. The power cable is supported by the support bracket at a position closer to a center of the arc relative to half of the radius of the arc when viewed from the vehicle width direction.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The technology disclosed in this specification relates to electric vehicles. The "electric vehicle" in this specification includes hybrid vehicles and fuel cell vehicles equipped with both a motor and an engine.

Background Art

[0002] In the electric vehicles disclosed in Patent Documents 1-3, the motor that drives the axle is supported by the suspension together with the axle. On the other hand, the inverter that supplies AC power to the motor is fixed to the vehicle body. That is, during driving, the motor swings relative to the inverter by the suspension.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] The inverter and the motor are electrically connected by a power cable. When the motor swings relative to the inverter, the power cable also swings. If a part of the power cable swings greatly, that part will fatigue and deteriorate. This specification provides a technique for suppressing the swing of the power cable connecting the motor and the inverter in an electric vehicle in which the motor is supported by a suspension.

Means for Solving the Problems

[0005] The electric vehicle disclosed in this specification includes an axle extending in the vehicle width direction, a motor connected to the axle and driving the axle, a suspension supporting the axle and the motor, an inverter fixed to the vehicle body and supplying power to the motor, a power cable connecting the inverter and the motor, and a support bracket supporting the power cable. The suspension swings the axle and the motor along an arc when viewed in the vehicle width direction. The support bracket swings together with the motor. The power cable is supported by the support bracket at a position closer to the center of the arc than half of the radius of the arc when viewed from the vehicle width direction. The swing amplitude of the support position of the power cable is equal to or less than half of the swing amplitude of the motor. The swing of the power cable is divided into the swing between the inverter and the support position and the swing between the support position and the motor. As a result, the swing of the power cable is suppressed.

[0006] The support bracket may typically extend from the motor toward the center of the arc. Also, the center of the arc may typically be the connection point of the suspension to the vehicle body. The details and further improvements of the technology disclosed in this specification will be described in the following "Mode for Carrying Out the Invention".

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0008] (First Embodiment) The electric vehicle 2 of the first embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 shows a plan view of the rear part of the electric vehicle 2, and FIG. 2 is a cross-sectional view of the electric vehicle 2 cut along line II-II in FIG. 1. FIGS. 1 and 2 show only the components around the suspension 10 of the electric vehicle 2.

[0009] The vehicle body in this embodiment means the frame of the vehicle (or the panel constituting the frame). The rear side members 3a and 3b are part of the vehicle body. The electric vehicle 2 has a motor 5, and the motor 5 drives the axle 4 of the rear wheels. The motor 5 is integrated with the axle 4. The motor 5 may include a reduction gear and a differential gear.

[0010] The axle 4 and the motor 5 are connected to the rear side members 3a and 3b (vehicle body) via the suspension 10. The suspension 10 includes a trailing arm 11 and a strut 12. In FIG. 1, the illustration of the strut 12 is omitted. The strut 12 includes a coil spring and a damper. The lower end of the strut 12 is connected to the axle 4, and the upper end of the strut 12 is connected to the upper end of the suspension tower provided on the body of the electric vehicle 2. In FIGS. 1 to 3, the illustration of the body including the suspension tower is omitted.

[0011] The trailing arm 11 is rotatably supported by the rear side members 3a and 3b at a pivot Pv in front of the axle 4. The pivot Pv corresponds to the connection point of the suspension 10 (trailing arm 11) to the vehicle body (rear side members 3a and 3b). When viewed from the vehicle width direction, the axle 4 and the motor 5 swing along an arc ARC around the pivot Pv.

[0012] An inverter 6 for supplying AC power to the motor 5 is fixed to the rear side member 3a. The inverter 6 and the motor 5 are connected by three power cables 7. The three power cables 7 are supported between the inverter 6 and the motor 5 by a fixing base 8 and a support bracket 21. The fixing base 8 is fixed to the rear side member 3a. The power cable 7 extending from the inverter 6 is fixed to the fixing base 8. The support bracket 21 extends forward from the motor 5, and the three power cables 7 are supported by a support portion 21a provided at the tip thereof.

[0013] The power cable 7 extends along the vehicle width direction between the fixing base 8 and the support bracket 21 (support portion 21a), bends at a right angle at the support bracket 21 (support portion 21a), and extends along the longitudinal direction of the vehicle body between the support bracket 21 (support portion 21a) and the motor 5.

[0014] The three power cables 7 are supported by the support bracket 21 at a position closer to the center of the arc ARC (i.e., the pivot Pv) than half of the radius R1 of the arc ARC. In other words, the distance Rd from the support point of the power cable 7 to the pivot Pv is shorter than R1 / 2. The support point is located between the pivot Pv and the motor 5.

[0015] When the electric vehicle 2 is running, the spring of the strut 12 expands and contracts according to the unevenness of the road surface, and the axle 4 and the motor 5 swing with respect to the vehicle body (rear side members 3a, 3b). The axle 4 and the motor 5 swing along an arc ARC around the pivot Pv. The motor 5 swings with respect to the inverter 6. Fig. 3 shows the displacement of the motor 5 when the axle 4 swings. The motor 5 and the inverter 6 are connected by a power cable 7, and the power cable 7 also swings. The support bracket 21 swings together with the motor 5. The power cable 7 is supported by the support bracket 21 at a position closer to the pivot Pv than half of the radius R1 of the arc ARC. Therefore, the swing amplitude of the support position (support portion 21a) of the power cable 7 is smaller than half of the swing amplitude of the motor 5. When the above-described structure is adopted, the swing of the power cable 7 is divided into the swing between the fixed base 8 and the support position, and the swing between the support position and the motor 5. And since the support position (support portion 21a of the support bracket 21) swings together with the motor 5, the swing amplitude between the support position of the power cable 7 and the motor 5 is small. When the above-described structure is adopted, the vibration of the power cable 7 is suppressed.

[0016] Also, the power cable 7 is fixed to the fixed base 8. In other words, the power cable 7 is fixed to the vehicle body (rear side member 3a) by the fixed base 8. The fixed base 8 can be expressed as the fixed position on the vehicle body side of the power cable 7. Between the fixed position on the vehicle body side (fixed base 8) and the support position on the motor side (support portion 21a of the support bracket 21), the power cable 7 mainly swings along a plane (first plane) orthogonal to the vehicle body front-rear direction. The power cable 7 bends at a right angle at the support position. Between the support position and the motor 5, the power cable 7 mainly swings along a plane (second plane) orthogonal to the vehicle width direction. The swing of the power cable 7 is divided into the swing in the first plane and the swing in the second plane. This also contributes to suppressing the vibration of the power cable 7.

[0017] (Second Embodiment) The electric vehicle 102 of the second embodiment will be described with reference to FIGS. 4 and 5. FIG. 4 is a cross-sectional view of the electric vehicle 102. FIG. 4 corresponds to FIG. 2. In the electric vehicle 102 of the second embodiment, the structure of the suspension 110 is different from that of the first embodiment. The suspension 110 includes a leaf spring 111, a strut 12, and a sub-damper 113. The leaf spring 111 is formed by stacking a plurality of elastic plates. The strut 12 is the same as that in the first embodiment. The front end of the leaf spring 111 is rotatably supported by the rear side member 3a at a pivot Pv. The pivot Pv corresponds to the connection point of the suspension 110 (leaf spring 111) to the vehicle body (rear side member 3a). The rear end of the leaf spring 111 is connected to the lower end of the sub-damper 113. The upper end of the sub-damper 113 is connected to the rear side member 3a. The strut 12 includes a coil spring and a main damper, and the sub-damper 113 serves as an auxiliary damper.

[0018] The axle 4 and the motor 5 are supported by the vehicle body (rear side member 3a) via the suspension 110. The axle 4 and the motor 5 are connected to the lower end of the strut 12 and attached to the middle of the leaf spring 111. The upper end of the strut 12 is rotatably connected to the body (not shown), and the lower end is rotatably connected to the axle 4.

[0019] During the running of the electric vehicle 102, as the road surface is uneven, the leaf spring 111 deforms, and the strut 12 and the sub-damper 113 expand and contract. FIG. 5 shows the displacement of the motor 5 when the axle swings. The front end of the leaf spring 111 is rotatably supported by the pivot Pv. The rear end of the leaf spring 111 is rotatably supported by the telescopic sub-damper 113. According to the expansion and contraction of the sub-damper 113, the rear end of the leaf spring 111 moves up and down. More precisely, as shown in FIG. 5, the rear end of the leaf spring 111 moves between the rear upper side and the front lower side. Therefore, the axle 4 and the motor 5 attached to the leaf spring 111 swing along an arc ARC centered on the pivot Pv generally. That is, the swinging direction of the axle 4 and the motor 5 is the same as that of the electric vehicle 2 in the first embodiment. The arrangements of the inverter 6, the fixed base 8, the support bracket 21, and the power cable 7 are the same as those of the electric vehicle 2 in the first embodiment. Therefore, the electric vehicle 102 in the second embodiment also has the same effect as the electric vehicle 2 in the first embodiment.

[0020] Enumerate the features of the electric vehicles 2 and 102. The axle 4 and the motor 5 are supported by the suspension 10 (110) and swing along an arc ARC centered on the pivot Pv during running. The support bracket 21 extends from the motor 5 to the front of the vehicle body, and the support bracket 21 also swings together with the motor 5. The power cable 7 is supported by the support bracket. The power cable 7 is supported by the support bracket 21 at a position closer to the center (pivot Pv) of the arc ARC than half of the radius (R1 / 2) of the arc ARC when viewed in the vehicle width direction. With this structure, the vibration of the power cable 7 during running is suppressed.

[0021] As described above, the center of oscillation (pivot Pv) of the axle 4 and the motor 5 is the connection point of the suspension 10 (110) to the vehicle body. The power cable 7 is fixed to the fixed base 8 on the vehicle body (rear side member 3a). The power cable 7 extends along the vehicle width direction between the fixed position on the vehicle body side (fixed base 8) and the support position on the motor side (support portion 21a of the support bracket 21), bends at a right angle at the support position, and extends along the vehicle body longitudinal direction between the support position and the motor 5. With this structure, the vibration of the power cable 7 is divided into two vibrations. This also contributes to suppressing the vibration of the power cable 7. The fact that the power cable 7 extends along the vehicle width direction between the fixed position (fixed base 8) and the support position (support portion 21a of the support bracket 21) means that, in the longitudinal direction of the vehicle body, the fixed position (fixed base 8) of the power cable 7 on the vehicle body side and the support position (support portion 21a of the support bracket 21) on the motor side are arranged at the same position.

[0022] Points to note regarding the technology described in the embodiments will be described. In the electric vehicle 2 of the first embodiment, the trailing arm 11 of the suspension 10 swings about the pivot Pv. In the electric vehicle 102 of the second embodiment, the leaf spring 111 swings generally about the pivot Pv. The technology disclosed in this specification is not limited to trailing arm type suspensions and leaf spring type suspensions. The technology disclosed in this specification is applicable to electric vehicles having a suspension in which the axle and the motor swing along an arc ARC centered on the pivot Pv when viewed from the vehicle width direction. In FIGS. 3 and 5, for the sake of understanding, the displacement of the axle 4 is exaggeratedly drawn.

[0023] The technology disclosed in this specification is applicable to electric vehicles having at least one motor that is supported by a suspension together with the axle and drives the axle. The "electric vehicle" disclosed in this specification may include a hybrid vehicle equipped with an engine in addition to the above motor. Further, the "electric vehicle" disclosed in this specification may include a fuel cell vehicle equipped with a fuel cell that supplies power to the motor.

[0024] The specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes to the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical utility either alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in this specification or the drawings can achieve multiple purposes simultaneously, and achieving one of these purposes itself has technical utility.

Explanation of Reference Numerals

[0025] 2, 102: Electric vehicle 3a, 3b: Rear side member 4: Axle 5: Motor 6: Inverter 7: Power cable 8: Fixed base 10, 110: Suspension 11: Trailing arm 12: Strut 21: Support bracket 21a: Support portion 111: Leaf spring 113: Sub-damper

Claims

1. An axle extending in the vehicle width direction, a motor connected to the axle and driving the axle, a suspension that supports the axle and the motor and swings the axle and the motor along an arc when viewed in the vehicle width direction, an inverter fixed to the vehicle body and supplying power to the motor, a power cable connecting the inverter and the motor, a support bracket that supports the power cable and swings together with the motor, characterized by comprising: the power cable is supported by the support bracket at a position closer to the center of the arc than half of the radius of the arc when viewed in the vehicle width direction, an electric vehicle.

2. The electric vehicle according to claim 1, wherein the center is a connection point of the suspension to the vehicle body.

3. The electric vehicle according to claim 2, wherein when the vehicle body is viewed in the vehicle width direction, the support bracket extends from the motor toward the center.

4. The electric vehicle according to any one of claims 1 to 3, wherein the power cable extends along the vehicle width direction between the support bracket and the inverter, bends at a right angle at the support bracket, and extends along the vehicle longitudinal direction between the support bracket and the motor.

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