JP7550902B1 - Electric vehicles - Google Patents

Abstract

[Solution] An electric vehicle 10 includes a drive unit 14 having an electric motor 26, and a support structure 20 that supports the drive unit 14 on a vehicle body 16. The support structure 20 has a front support member 54 arranged on the front side of the drive unit 14. The front support member 54 has a width smaller than the width of the drive unit 14 in the vehicle width direction of the vehicle body 16. The front support member 54 extends from the drive unit 14 toward the front of the vehicle body 16, intersects with the torsion beam 38, and is fixed to the vehicle body 16 on the front side of the torsion beam 38.
[Selected figure] Figure 2

Description

The present invention relates to an electric vehicle that can be driven by a drive unit.

In recent years, efforts to realize a low-carbon or carbon-free society have been intensified, and research and development of electrification technology has been conducted to reduce _CO2 emissions and improve energy efficiency in vehicles. Patent Document 1 discloses an electric vehicle equipped with a vehicle rear structure including a motor. The vehicle rear structure includes an electric motor, a torsion beam suspension, and a support member that supports the electric motor. The suspension includes a torsion beam that connects a pair of trailing arms. The support member is fixed to the vehicle body in a bifurcated shape that branches forward of the electric motor and in the vehicle width direction to avoid interference with the trailing arms.

Patent No. 5552962

However, in Patent Document 1, which is about electrification technology, the support member is fixed to the vehicle body at two points in front of the electric motor of the electric vehicle, which causes the support member to become large.

The present invention aims to solve the above problems by simplifying the support structure that receives the load in the forward and backward directions when the electric vehicle is running, thereby reducing its weight and achieving a reduction in manufacturing costs. The aim is also to contribute to improving energy efficiency.

An aspect of the present invention is an electric vehicle that includes a vehicle body, a drive unit having an electric motor attached to the vehicle body and driven by electricity, a suspension device that connects a pair of trailing arms supported on the vehicle body and spaced apart in the vehicle width direction of the vehicle body to each other by a torsion beam extending in the vehicle width direction, and a support structure that supports the drive unit on the vehicle body, in which the drive unit is disposed rearward of the torsion beam and drives rear wheels provided on the vehicle body by the drive unit, and the support structure has a front support member that is disposed forward of the drive unit in the fore-and-aft direction of the vehicle body, the front support member has a width smaller than the width of the drive unit in the vehicle width direction of the vehicle body, extends from the drive unit toward the front of the vehicle body, intersects the torsion beam, and is fixed to the vehicle body on the forward side of the torsion beam.

According to the present invention, the front support member can efficiently bear the load in the front-rear direction that occurs on the drive unit when the electric vehicle is traveling and accelerating or decelerating, so the support structure that bears the load in the front-rear direction can be simplified and made lighter than a structure that uses a front support member that is larger than the width of the drive unit. This makes it possible to reduce the manufacturing costs of the electric vehicle.

FIG. 1 is an overall explanatory diagram of an electric vehicle according to an embodiment of the present invention. FIG. 2 is a plan view of the rear end and its vicinity of the vehicle body as viewed from below. FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG.

As shown in FIG. 1, the electric vehicle 10 according to this embodiment is an electric vehicle (EV) equipped with a drive unit 14 that is driven by the power of a battery 12. Note that the electric vehicle 10 is not limited to an electric vehicle. As long as the vehicle uses a battery 12, it can be applied to various electric vehicles 10 such as a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), or a fuel cell vehicle (FCV).

The electric vehicle 10 includes a vehicle body 16, a drive unit 14 that is attached to the vehicle body 16 and driven by electricity, a suspension device 18 that supports the rear wheels 24R, and a support structure 20 that supports the drive unit 14 on the vehicle body 16.

The vehicle body 16 includes a frame 17 and a floor panel 22 that constitutes the lower part of the vehicle body 16. The floor panel 22 extends along the front-rear direction (arrow A direction) of the electric vehicle 10. A front wheel 24F is rotatably supported at the front of the frame 17 of the vehicle body 16 via a front suspension device (not shown). A rear wheel 24R is rotatably supported at the rear of the frame 17 of the vehicle body 16. The floor panel 22 is disposed approximately parallel to the road surface G (ground) that the front wheel 24F and the rear wheel 24R contact. As shown in FIG. 2, the frame 17 has first and second cross members 171 and 172 that extend in the vehicle width direction. The first cross member 171 is disposed between the pair of rear wheels 24R. The second cross member 172 is disposed in front of the first cross member 171.

2, the drive unit 14 has, for example, an electric motor 26 and a reduction gear. The electric motor 26 is, for example, a motor that rotates by electricity. The drive unit 14 is disposed in the area of the rear end 221 of the floor panel 22 via the support structure 20. The drive unit 14 drives the rear wheels 24R. The drive unit 14 is disposed in the rear end 221 of the floor panel 22, approximately in the center of the vehicle width direction (arrow B direction). The drive unit 14 is disposed forward of the rear end 161 of the vehicle body 16 (floor panel 22). The drive unit 14 is disposed between the pair of rear wheels 24R. As shown in FIG. 3, the drive unit 14 is disposed protruding downward from the floor panel 22 in the vehicle height direction (arrow C direction) of the electric vehicle 10. Note that a drive unit for driving the front wheels 24F may be provided in front of the frame 17, separate from the drive unit 14 for driving the rear wheels 24R.

As shown in FIG. 2, the drive unit 14 has a housing 28 that incorporates an electric motor 26 and a reduction gear. The electric motor 26 can rotate within the housing 28 using electric power. A rotating shaft 30 is attached to the center of rotation of the reduction gear. The rotating shafts 30 of the drive unit 14 extend on both sides of the housing 28 in the vehicle width direction. When the electric motor 26 is driven, the rotating shaft 30 rotates via the reduction gear. Note that the drive unit 14 is not limited to a configuration that includes the electric motor 26 and the reduction gear. The drive unit 14 may be composed of only the electric motor 26.

A pair of drive shafts 34 are connected to the end of the rotating shaft 30 via joints 32. The pair of drive shafts 34 are arranged along the vehicle width direction (arrow B direction) of the vehicle body 16. The rotating shaft 30 and the rear wheel 24R are connected to each other via the drive shafts 34.

The suspension device 18 includes a pair of trailing arms 361, 362, a torsion beam 38 that connects the pair of trailing arms 361, 362 to each other, and a damper 40 and a spring 42 that are held by the trailing arms 361, 362.

The pair of trailing arms 361, 362 extend along the front-rear direction (arrow A direction) of the vehicle body 16 and are spaced apart from each other in the vehicle width direction (arrow B direction) of the vehicle body 16. The pair of trailing arms 361, 362 are arranged inward in the vehicle width direction with respect to the rear wheel 24R. The front ends of the pair of trailing arms 361, 362 are supported to be swingable relative to the second cross member 172 of the vehicle body 16. In the front-rear direction of the vehicle body 16, the rear wheel 24R is supported at the rear of the pair of trailing arms 361, 362. The rear ends of the trailing arms 361, 362 swing in a direction approaching or moving away from the floor panel 22 with the front ends of the trailing arms 361, 362 as fulcrums, so that the rear wheel 24R is supported by the trailing arms 361, 362 to be swingable in the up-down direction.

The trailing arms 361, 362 include a damper receiving portion 44 and a spring receiving portion 46. The damper receiving portion 44 is provided at the rear end of the trailing arms 361, 362. The damper 40 is held between the damper receiving portion 44 and the vehicle body 16. The damper 40 is disposed so as to be approximately perpendicular to the floor panel 22 (see FIG. 4). The spring receiving portion 46 protrudes inward in the vehicle width direction from approximately the center of the trailing arms 361, 362. The spring 42 is held between the spring receiving portion 46 and the vehicle body 16. The spring 42 is, for example, a coil spring. The resilience of the spring 42 is biased in a direction (vehicle height direction) that is approximately perpendicular to the floor panel 22.

When the electric vehicle 10 is traveling, the load input from the road surface G to the rear wheel 24R is absorbed by the spring 42 and damped by the damper 40.

As shown in FIG. 2, the torsion beam 38 is disposed along the vehicle width direction (direction of arrow B) of the vehicle body 16. The torsion beam 38 is disposed forward of the drive unit 14. In other words, the drive unit 14 is disposed rearward of the torsion beam 38. The torsion beam 38 is disposed rearward of the front ends of the trailing arms 361, 362.

The torsion beam 38 has a pair of connecting parts 481, 482 connected to the trailing arms 361, 362 at both ends. When viewed from the front of the vehicle body 16 shown in FIG. 4, the connecting parts 481, 482 are arranged at approximately the same height as the central axis of the rear wheel 24R in the vehicle height direction. The height of the connecting parts 481, 482 is not limited to being arranged at approximately the same height as the central axis of the rear wheel 24R. As shown in FIG. 2, the torsion beam 38 is connected to the trailing arms 361, 362 at a position rearward of the front ends of the trailing arms 361, 362. The connecting parts 481, 482 of the torsion beam 38 are attached to the trailing arms 361, 362 from below and fixed by welding or the like. When the pair of trailing arms 361, 362 swing together with the rear wheel 24R while the electric vehicle 10 is traveling, the torsion beam 38 swings along with the trailing arms 361, 362.

As shown in FIG. 4, the torsion beam 38 has an intersection 50 that is curved upwardly and convexly when viewed from the front of the vehicle body 16. The intersection 50 is provided in the approximate center of the extension direction of the torsion beam 38, which is the vehicle width direction of the vehicle body 16. The intersection 50 gradually curves upwardly and gently from the pair of connecting portions 481, 482 toward the center in the extension direction. The torsion beam 38 including the intersection 50 is formed in an approximately arc shape. The upper surface 501 of the intersection 50 curves upwardly and convexly toward the floor panel 22. The lower surface 502 of the intersection 50 curves upwardly and concavely. The upper part of the intersection 50 and the floor panel 22 are spaced apart in the vehicle height direction.

As shown in FIG. 2, the support structure 20 has a plurality of support members 52. The plurality of support members 52 includes a front support member 54 and a rear support member 56.

The front support member 54 is disposed in front of the drive unit 14 in the front-rear direction of the vehicle body 16. The front support member 54 is formed in a plate shape with a plate thickness direction being the vehicle width direction of the vehicle body 16. The front support member 54 extends linearly from the drive unit 14 toward the front of the vehicle body 16. That is, in the plan view of the vehicle body 16 shown in FIG. 2, the front support member 54 is formed linearly along the front-rear direction (arrow A direction). As shown in FIG. 3, the rear end 541R of the front support member 54 is connected to the front end of the housing 28 in the drive unit 14 by a bolt 58. The width H of the front support member 54 in the vehicle height direction decreases as it moves forward from the drive unit 14. The width H of the front support member 54 in the vehicle height direction is greatest at the rear end 541R of the front support member 54.

As shown in FIG. 2, in the vehicle width direction of the vehicle body 16, the width W1 of the front support member 54 is smaller than the width W2 (width of the housing 28) of the drive unit 14 (W1<W2). In the vehicle width direction of the vehicle body 16 (direction of arrow B), the front support member 54 is disposed and connected within the width region between one width end 281 and the other width end 282 of the housing 28 of the drive unit 14.

As shown in FIG. 2, in a plan view seen from the vehicle height direction perpendicular to the front-rear direction of the vehicle body 16 and perpendicular to the vehicle width direction, the front support member 54 and the intersection 50 of the torsion beam 38 intersect. As shown in FIG. 4, when viewed from the front of the vehicle body 16, the intersection 50 is curved upward and separated from the front support member 54. The front support member 54 and the intersection 50 are separated in the vehicle height direction.

As shown in FIG. 2, the front end 541F of the front support member 54 is fixed to the vehicle body 16 forward of the torsion beam 38. The front end 541F of the front support member 54 is supported by a mount member 60 provided on the underside of the second cross member 172. The front end 541F of the front support member 54 is inserted and held in the center of an elastic member 62 inside the mount member 60. Vibrations of the front end 541F of the front support member 54 are absorbed and mitigated by the elastic member 62.

The rear support member 56 is disposed behind the drive unit 14 in the fore-and-aft direction (direction of arrow A) of the vehicle body 16. The rear support member 56 is disposed between the rear end 161 of the vehicle body 16 (floor panel 22) and the drive unit 14.

The rear support member 56 includes a rod member 64, a connection member 66 that connects the rod member 64 and the drive unit 14, and a plurality of fixing portions 68 provided at both ends of the rod member 64. The rod member 64 is formed in an axial shape and is arranged along the vehicle width direction (arrow B direction) of the vehicle body 16. The rod member 64 is arranged approximately parallel to the rotating shaft 30 of the drive unit 14. The length of the rod member 64 in the vehicle width direction is longer than the width W2 of the drive unit 14 (the width of the housing 28). Note that the length of the rod member 64 is not limited to being longer than the width W2 of the drive unit 14.

The connecting member 66 is connected to the longitudinal center of the rod member 64. The connecting member 66 extends forward relative to the rod member 64. As shown in FIG. 3, the connecting member 66 is connected to the rear end of the housing 28 of the drive unit 14 via a bolt 70. The bolt 70 is fastened in the width direction of the vehicle body 16. This connects the rod member 64 of the rear support member 56 to the rear end of the drive unit 14. Note that the fastening direction of the connecting member 66 is not limited to the width direction of the vehicle body 16. The connecting member 66 may be fastened in the fore-and-aft direction to the rear end of the drive unit 14.

The multiple fixing parts 68 fix the rod member 64 to the floor panel 22 of the vehicle body 16. The multiple fixing parts 68 are, for example, a pair of fixing parts 681, 682 arranged at both ends of the rod member 64. Below, a case where the rear support member 56 has a pair of fixing parts 681, 682 will be described. The pair of fixing parts 681, 682 are spaced apart in the longitudinal direction (arrow B direction) of the rod member 64 with the rod member 64 therebetween. The pair of fixing parts 681, 682 are fixed by fastening members 74 in a state of abutting against an attachment part 72 provided on the lower surface 223 of the floor panel 22. The fixing direction of the fixing parts 681, 682 is the up-down direction (arrow C direction) perpendicular to the extension direction (arrow B direction) of the rod member 64. The fixing parts 681, 682 are fixed toward the floor panel 22 by the fastening members 74.

This embodiment provides the following advantages:

2, the electric vehicle 10 includes a vehicle body 16, a drive unit 14 having an electric motor 26 attached to the vehicle body 16 and driven by electricity, a suspension device 18 that connects a pair of trailing arms 361, 362 supported by the vehicle body 16 and spaced apart in the vehicle width direction of the vehicle body 16 with a torsion beam 38 extending in the vehicle width direction, and a support structure 20 that supports the drive unit 14 on the vehicle body 16. The drive unit 14 is disposed behind the torsion beam 38, and the support structure 20 has a front support member 54 that is disposed on the front side of the drive unit 14 in the fore-and-aft direction (arrow A direction) of the vehicle body 16. The front support member 54 has a width W1 that is smaller than the width W2 of the drive unit 14 in the vehicle width direction (arrow B direction) of the vehicle body 16. The front support member 54 extends from the drive unit 14 toward the front of the vehicle body 16, intersects with the torsion beam 38, and is fixed to the vehicle body 16 on the front side of the torsion beam 38.

With this configuration, when the electric vehicle 10 is traveling, the load in the fore-and-aft direction that occurs on the drive unit 14 when the vehicle accelerates or decelerates can be efficiently received by the front support member 54. Therefore, compared to a structure that uses a front support member that is larger than the width W2 of the drive unit 14, the support structure 20 that receives the load in the fore-and-aft direction can be simplified and made lighter. This makes it possible to reduce the manufacturing costs of the electric vehicle 10.

The front support member 54 is disposed within a width region between one width end 281 and the other width end 282 of the drive unit 14 (housing 28) in the vehicle width direction, so that the front support member 54 can support a position close to the center of gravity of the drive unit 14 in the vehicle width direction of the vehicle body 16. This allows the front support member 54 to effectively reduce the load generated when the electric vehicle 10 is traveling.

In a plan view from the vehicle height direction perpendicular to the fore-aft direction of the vehicle body 16 and perpendicular to the vehicle width direction, the torsion beam 38 has an intersection 50 that intersects with the front support member 54, and as shown in FIG. 4, the intersection 50 is spaced apart from the front support member 54 and curved upwardly in a convex shape.

According to this configuration, by curving the intersection 50 of the torsion beam 38 upward, the front support member 54 and the torsion beam 38 can effectively intersect in a plan view. This allows the support structure 20 to be compact, and the mounting space of the vehicle body 16 to be used efficiently. By curving the torsion beam 38 upward, the roll center when the vehicle body 16 rolls can be raised, improving handling stability.

The support structure 20 includes a rear support member 56 disposed behind the drive unit 14, and the rear support member 56 has a plurality of fixing parts 681, 682 fixed to the vehicle body 16, and is fixed to the vehicle body 16 by the plurality of fixing parts 681, 682. With this configuration, when a large load is generated by the driving torque of the drive unit 14 during acceleration or deceleration of the electric vehicle 10, the load acting in the vehicle width direction (left and right direction) can be effectively alleviated by being received by the rear support member 56 fixed by the plurality of fixing parts 681, 682. In the front-rear direction of the vehicle body 16, the mounting pitch P between the fixing point of the front support member 54 and the fixing point of the rear support member 56 to the vehicle body 16 can be secured, so that the large load caused by the driving torque of the drive unit 14 can be effectively alleviated. When the electric vehicle 10 accelerates, the noise and vibration of the drive unit 14 can be suppressed from being transmitted to the vehicle body 16.

As shown in FIG. 3, the width H of the front support member 54 in the vehicle height direction decreases as it moves forward from the drive unit 14. With this configuration, the front support member 54 extends along the fore-and-aft direction of the vehicle body 16, so that the drive unit 14 can be supported more reliably, and the front support member 54 can provide sufficient load-bearing performance. Since the width H of the front side of the front support member 54 in the vehicle height direction can be reduced, the support structure 20 can be made lightweight and compact.

As shown in FIG. 2, in a plan view of the vehicle body 16, the front support member 54 is formed linearly along the fore-and-aft direction, making it easy to form the front support member 54, reducing manufacturing costs and improving assembly workability. The front support member 54 can more efficiently bear the fore-and-aft load generated in the drive unit 14 when the vehicle accelerates or decelerates.

The front support member 54 is formed in a plate shape, and the plate thickness direction of the front support member 54 is the vehicle width direction of the vehicle body 16. This makes it possible to realize the front support member 54 at low cost.

The above embodiments can be summarized as follows:

The above embodiment is an electric vehicle (10) comprising a vehicle body (16), a drive unit (14) having an electric motor (26) attached to the vehicle body and driven by electricity, a suspension device (18) that connects a pair of trailing arms (361, 362) supported on the vehicle body and spaced apart in the vehicle width direction of the vehicle body to each other by a torsion beam (38) extending in the vehicle width direction, and a support structure (20) that supports the drive unit on the vehicle body, the drive unit being disposed rearward of the torsion beam, and the drive unit driving rear wheels (24R) provided on the vehicle body, the support structure having a front support member (54) disposed on the front side of the drive unit in the fore-and-aft direction of the vehicle body, the front support member having a width (W1) smaller than the width (W2) of the drive unit in the vehicle width direction of the vehicle body, extending from the drive unit toward the front of the vehicle body, intersecting the torsion beam, and fixed to the vehicle body on the front side of the torsion beam.

The front support member is disposed within a width region between one end (281) and the other end (282) of the drive unit in the vehicle width direction.

When viewed from a height direction perpendicular to the longitudinal direction of the vehicle body and perpendicular to the width direction of the vehicle, the torsion beam has an intersection portion (50) that intersects with the front support member, and the intersection portion is spaced apart from the front support member and curved upwardly in a convex shape.

The support structure includes a rear support member (56) disposed behind the drive unit, the rear support member having a plurality of fixing parts (681, 682) that are fixed to the vehicle body, and is fixed to the vehicle body by the plurality of fixing parts.

The width (H) of the front support member in the vehicle height direction decreases as it moves from the drive unit to the front.

In a plan view of the vehicle body, the front support member is formed linearly along the fore-and-aft direction.

The front support member is formed in a plate shape, and the thickness direction of the front support member is the vehicle width direction of the vehicle body.

The present invention is not limited to the above disclosure, and various configurations may be adopted without departing from the gist of the present invention.

10... Electric vehicle 14... Drive unit 16... Vehicle body 18... Suspension device 20... Support structure 26... Electric motors 361, 362... Trailing arm 38... Torsion beam 54... Front support member

Claims (7)

The car body and
a drive unit having an electric motor attached to the vehicle body and driven by electric power;
a suspension device that connects a pair of trailing arms supported by the vehicle body and spaced apart in a vehicle width direction of the vehicle body to each other by a torsion beam extending in the vehicle width direction;
a support structure for supporting the drive unit on the vehicle body;
Equipped with
an electric vehicle in which the drive unit is disposed rearward of the torsion beam and the drive unit drives rear wheels provided on the vehicle body,
the support structure includes a front support member that is disposed on a front side of the drive unit in a front-rear direction of the vehicle body,
An electric vehicle, wherein the front support member has a width smaller than a width of the drive unit in a vehicle width direction of the vehicle body, extends from the drive unit toward the front of the vehicle body, intersects the torsion beam, and is fixed to the vehicle body on the forward side of the torsion beam. The electric vehicle according to claim 1,
An electric vehicle, wherein the front support member is disposed within a width region between one end and the other end of the drive unit in the vehicle width direction. 3. The electric vehicle according to claim 1,
In a plan view seen from a height direction perpendicular to the front-rear direction of the vehicle body and perpendicular to the vehicle width direction, the torsion beam has an intersection portion that intersects with the front support member,
The intersection portion is spaced apart from the front support member and is curved convexly upward. 3. The electric vehicle according to claim 1,
the support structure includes a rear support member disposed rearward of the drive unit;
The rear support member has a plurality of fixing portions that are fixed to the vehicle body, and is fixed to the vehicle body by the plurality of fixing portions. The electric vehicle according to claim 1,
The front support member has a width in a vehicle height direction that decreases from the drive unit toward the front. 3. The electric vehicle according to claim 1,
In a plan view of the vehicle body, the front support member is formed linearly along the front-rear direction. The electric vehicle according to claim 5,
The front support member is formed in a plate shape, and a plate thickness direction of the front support member is the vehicle width direction of the vehicle body.

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