JP2021187232A - Vehicle lower part structure - Google Patents

Abstract

To obtain a vehicle lower part structure which enables improvement of aerodynamic performance of a vehicle.SOLUTION: A vehicle lower part structure 10 includes: a fuel tank 20 disposed at a lower part of a vehicle 12, which is located on the vehicle body rear side relative to an engine, and at a center part in a vehicle width direction; a battery 30 which is disposed at the vehicle body rear side relative to the fuel tank 20 and the center part in the vehicle width direction and serves as a power source for driving a traveling motor mounted on the vehicle 12; an exhaust pipe 40 which extends from the engine to the vehicle body rear side passing through the outer side of the fuel tank 20 and the battery 30 in a vehicle width direction; and an undercover 50 which covers lower surfaces of the fuel tank 20 and the battery 30.SELECTED DRAWING: Figure 4

Description

The present invention relates to a vehicle lower structure.

The fuel tank is located on the rear side of the vehicle body of the engine and in the center of the vehicle under the floor in the vehicle width direction, and on the rear side of the vehicle body of the fuel tank and in the center of the vehicle under the floor in the vehicle width direction. The vehicle underfloor structure in which the vehicle is arranged is conventionally known (see, for example, Patent Document 1).

In this underfloor structure of the vehicle, a recess for passing an inlet pipe extending from the fuel tank to the rear side of the vehicle body is formed on the upper surface of the battery along the front-rear direction of the vehicle body, and extends from the engine to the rear side of the vehicle body on the lower surface of the battery. A recess for passing an existing exhaust pipe is formed along the front-rear direction of the vehicle body.

Japanese Unexamined Patent Publication No. 2017-077783

However, when a recess for passing the exhaust pipe is formed on the lower surface of the battery and the exhaust pipe passes through the central portion in the vehicle width direction at the lower part of the vehicle, the undercover is divided into left and right so as to avoid the exhaust pipe. Since it does not cover the central part in the vehicle width direction, the airflow may be disturbed and the aerodynamic performance may deteriorate when the vehicle is running. As described above, there is still room for improvement from the viewpoint of improving the aerodynamic performance of the vehicle.

Therefore, an object of the present invention is to obtain a vehicle lower structure capable of improving the aerodynamic performance of the vehicle.

In order to achieve the above object, the vehicle lower structure according to claim 1 according to the present invention includes a fuel tank arranged at the lower part of the vehicle on the rear side of the vehicle body with respect to the engine and at the center in the vehicle width direction. A battery that is arranged on the rear side of the vehicle body of the fuel tank and in the center in the vehicle width direction and is a power source for driving a traveling motor mounted on the vehicle, and the vehicle width of the fuel tank and the battery from the engine. It includes an exhaust pipe extending to the rear side of the vehicle body through the outside in the direction, and an undercover that covers the lower surfaces of the fuel tank and the battery.

According to the first aspect of the present invention, the exhaust pipe extends to the rear side of the vehicle body through the outside of the fuel tank and the battery in the vehicle width direction. Therefore, the undercover can cover the lower surface of the fuel tank and the battery. That is, the undercover can cover the central portion in the vehicle width direction at the lower portion of the vehicle. Therefore, when the vehicle is running, the turbulence of the airflow is suppressed and the aerodynamic performance is improved.

As described above, according to the present invention, the aerodynamic performance of the vehicle can be improved.

It is a perspective view which shows the vehicle lower structure which concerns on this embodiment when viewed from diagonally above. It is a side view which shows the vehicle which provided the vehicle lower structure which concerns on this embodiment. It is a top view which shows the vehicle lower structure which concerns on this embodiment. It is a bottom view which shows the vehicle lower structure which concerns on this embodiment. It is a front sectional view which shows the battery pack which constitutes the vehicle lower structure which concerns on this embodiment. It is a front sectional view which shows the battery pack which constitutes the vehicle lower structure which concerns on the comparative example.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the examples shown in the drawings. For convenience of explanation, the arrow UP shown appropriately in each figure is the vehicle body upward direction, the arrow FR is the vehicle body front direction, and the arrow RH is the vehicle body right direction. In addition, in the following explanation, when the up / down, front / rear, and left / right directions are described without special mention, it means the up / down in the up / down direction of the vehicle body, the front / rear in the front / rear direction of the vehicle body, and the left / right in the left / right direction of the vehicle body (vehicle width direction). do.

As shown in FIGS. 1 to 3, the vehicle lower structure 10 according to the present embodiment is on the lower side of the vehicle body of the floor panel (not shown) constituting the floor of the vehicle 12, and is the axle of the front wheel (not shown). It has a fuel tank 20 arranged between an axle (not shown) of a rear wheel 14 (see FIG. 2) and a battery pack 30 as a battery (not shown).

On both sides of the vehicle 12, a pair of left and right rockers 16 having a closed cross-sectional shape extending in the front-rear direction of the vehicle body (only the rocker 16R on the right side is shown in FIG. 3) are provided, and the inside of each rocker 16 in the vehicle width direction. The outer end portion of the floor panel in the vehicle width direction is joined to the lower surface of the rocker inner panel 18 constituting the panel.

An engine (not shown) is mounted on the front portion of the vehicle 12, and gasoline as fuel to be supplied to the engine is stored in the fuel tank 20. Further, a traveling motor for driving the front wheels (not shown) is mounted on the front portion of the vehicle 12 (between the left and right front wheels), and the battery pack 30 serves as a power source for driving the traveling motor. ing.

That is, the vehicle 12 is a hybrid vehicle (including a plug-in hybrid vehicle) that can run not only on gasoline but also on electricity, or an electric vehicle that runs by generating electricity with an engine. The battery pack 30 is arranged close to the rear side of the vehicle body of the fuel tank 20. In other words, the fuel tank 20 is arranged close to the front side of the vehicle body of the battery pack 30.

More specifically, the fuel tank 20 is arranged at substantially the center of the front seat 26 (see FIG. 2) on the lower side of the vehicle body in the vehicle width direction. In other words, the fuel tank 20 is arranged on the lower side of the vehicle body of the tunnel portion (not shown) provided so as to extend in the front-rear direction between the left and right front seats 26. Further, the fuel tank 20 is formed of a resin material in a substantially "T" shape in a plan view, and the rear side is formed narrower than the front side (see FIGS. 1 and 3).

The battery pack 30 is arranged at a substantially central portion in the vehicle width direction on the lower side of the vehicle body of the rear seat 28 (see FIG. 2). The battery pack 30 is formed in a substantially rectangular shape in which the vehicle width direction is longer than the vehicle body front-rear direction in a plan view, and has a large number of battery cells 32 inside as shown in FIG.

As shown in FIGS. 1 to 3, a fuel filler port 22 for supplying gasoline to the fuel tank 20 is arranged on the upper rear side of the vehicle body of the battery pack 30. The fuel tank 20 and the fuel filler port 22 are communicated with each other by an inlet pipe 24. That is, the front end portion (one end portion) of the inlet pipe 24 is communicated with the rear end portion of the fuel tank 20, and the rear end portion (end end portion) of the inlet pipe 24 is communicated with the fuel filler port 22.

Further, the inlet pipe 24 is piped on the upper side of the vehicle body of the battery pack 30. Specifically, a recess 34 (see also FIG. 5) having a substantially semicircular cross section and extending in the front-rear direction of the vehicle body is formed in the substantially central portion of the upper surface of the battery pack 30 in the vehicle width direction. A part of the inlet pipe 24 extending in the front-rear direction of the vehicle body is piped so as to pass through the recess 34 thereof.

Further, the exhaust pipe 40 is piped from the substantially central portion in the vehicle width direction of the engine toward the rear side of the vehicle body. A catalyst 42 is communicated and connected to a part of the exhaust pipe 40 that is piped between the engine and the fuel tank 20 in a plan view or a side view. By this catalyst 42, harmful substances in the exhaust gas discharged from the engine to the exhaust pipe 40 are oxidized or reduced to be purified.

Further, the exhaust pipe 40 on the rear side of the vehicle body with respect to the catalyst 42 is bent toward the right side (outside in the vehicle width direction) and further bent toward the rear side of the vehicle body. That is, the exhaust pipe 40 extends to the rear side of the vehicle body through the right side (outside in the vehicle width direction) of the fuel tank 20. A part of the exhaust pipe 40 passing through the right side of the fuel tank 20 has a double pipe structure and is a sub muffler portion 44.

The exhaust pipe 40 extending to the rear side of the vehicle body through the right side of the fuel tank 20 extends to the rear side of the vehicle body through the right side of the battery pack 30, that is, the inside of the rocker 16R on the right side in the vehicle width direction. There is. Then, the exhaust pipe 40 extending to the rear side of the vehicle body through the right side of the battery pack 30 is bent inward (left side) in the vehicle width direction on the rear side of the vehicle body of the battery pack 30 and further to the rear side of the vehicle body. It is bent and extended toward the main muffler 46 and is connected to the main muffler 46 in communication.

The main muffler 46 is formed in a substantially elliptical pillar shape whose axial direction is the vehicle width direction, and the exhaust pipe 40 is communicated with and connected to a substantially central portion in the vehicle width direction at the front end portion of the main muffler 46. Then, the muffler cutter 48 extends from the side portion of the main muffler 46 toward the rear side of the vehicle body.

Further, as shown in FIG. 2, the lower surface of the fuel tank 20 and the lower surface of the battery pack 30 form a substantially flat surface. Then, as shown in FIG. 4, the lower part of the vehicle 12 is formed in a shape so as to avoid the exhaust pipe 40 and the main muffler 46 (exhaust pipe 40 and the main muffler 46 are exposed to the lower side of the vehicle body). The undercover 50 is provided.

The undercover 50 is formed in a flat plate shape divided into two front and rear parts, and is a front cover 52 that covers the lower side of the vehicle body of the engine and a rear cover 54 that covers the lower side of the vehicle body on the rear side of the front cover 52. And, it is composed of. The rear cover 54 covers the entire lower surface of the fuel tank 20 and the entire lower surface of the battery pack 30 from the lower side of the vehicle body.

That is, since the exhaust pipe 40 extends to the rear side of the vehicle body through the right side (outside in the vehicle width direction) of the fuel tank 20 and the battery pack 30, the rear cover 54 (undercover 50) is the exhaust pipe 40. It is possible to cover the entire lower surface of the fuel tank 20 and the entire lower surface of the battery pack 30 from the lower side of the vehicle body even if the fuel tank 20 is provided so as to avoid the above. It is possible to cover the entire area.

Next, the operation of the vehicle lower structure 10 according to the present embodiment having the above configuration will be described.

As described above, the undercover 50 (rear cover 54) provided so as to avoid the exhaust pipe 40 can cover the entire lower surface of the fuel tank 20 and the entire lower surface of the battery pack 30 from the lower side of the vehicle body. That is, the undercover 50 (rear cover 54) can cover the central portion of the lower portion of the vehicle 12 in the vehicle width direction in the front-rear direction.

Therefore, as compared with the configuration in which the undercover 50 does not cover the central portion in the vehicle width direction in the front-rear direction, it is possible to suppress the turbulence of the air flow when the vehicle 12 is traveling. Therefore, the aerodynamic performance of the vehicle 12 can be improved, and the fuel efficiency of the vehicle 12 can be improved. Further, even when the vehicle 12 travels on a snowy road, the undercover 50 can reduce snow clogging and the like, so that it is possible to prevent problems from occurring.

Further, in the vehicle lower structure 10 according to the present embodiment, the heavy fuel tank 20 and the battery pack 30 are located between the axles of the front wheels and the axles of the rear wheels 14, and are front and rear on the lower side of the vehicle body of the floor panel. They are arranged side by side. Therefore, the load sharing on the front side and the rear side of the vehicle 12 can be optimized, and the center of gravity of the vehicle 12 can be lowered. Therefore, the kinetic performance of the vehicle 12 can also be improved.

If the fuel tank 20 and the battery pack 30 are arranged on the lower side of the vehicle body of the floor panel, there is an advantage that the design of the body on the upper side thereof is not restricted. Further, when the battery pack 30 is arranged on the lower side of the vehicle body of the floor panel (rear seat 28), the battery pack 30 is arranged on the rear side of the vehicle body of the rear seat 28, as compared with the configuration of the vehicle 12. There is also the advantage of being able to expand the luggage space.

Further, an inlet pipe 24 is piped on the upper side of the vehicle body of the battery pack 30. Therefore, the inlet pipe 24 can be protected by the battery pack 30. That is, when the vehicle 12 is traveling, the battery pack 30 can suppress or prevent the stepping stones and the like from colliding with the inlet pipe 24 (the impact is applied to the inlet pipe 24).

Further, a recess 34 in which a part of the inlet pipe 24 is arranged is formed in a substantially central portion in the vehicle width direction on the upper surface of the battery pack 30. Therefore, the battery pack 30 (recessed portion 34) allows the inlet pipe 24 to be arranged away from the exhaust pipe 40. Therefore, the heat damage to the inlet pipe 24 by the exhaust pipe 40 can also be reduced.

Further, as shown in FIG. 6, in the vehicle lower structure 11 according to the comparative example, a recess having a substantially semicircular cross section and extending in the front-rear direction of the vehicle body at a substantially central portion in the vehicle width direction on the lower surface of the battery pack 36. 38 is formed. A part of the exhaust pipe 40 extending in the front-rear direction of the vehicle body is piped so as to pass through the recess 38.

On the other hand, the exhaust pipe 40 in the vehicle lower structure 10 according to the present embodiment is piped so as to extend to the rear side of the vehicle body through between the right side of the fuel tank 20 and the battery pack 30 and the rocker 16R on the right side. Has been done. Therefore, as shown in FIG. 5, it is not necessary to form a recess 38 for passing the exhaust pipe 40 on the lower surface of the battery pack 30.

Therefore, the rigidity of the battery pack 30 can be increased as compared with the rigidity of the battery pack 36 in the comparative example, and the side collision of the vehicle 12 can be dealt with more effectively. That is, even if a load is input to the battery pack 30 from the outside in the vehicle width direction at the time of a side collision of the vehicle 12, the battery pack 30 can protect the inlet pipe 24. Therefore, the safety of the vehicle 12 can be improved.

Further, since the concave portion 38 is not formed on the lower surface of the battery pack 30 (because the lower surface of the battery pack 30 can be formed on a flat surface), the number of battery cells 32 provided inside the battery pack 30 is shown in the comparative example. The number can be increased more than the number of battery cells 32 provided inside the battery pack 36 (the battery cells 32 cannot be provided in the space sandwiched from the vertical direction by the recess 34 and the recess 38 of the battery pack 36 in the comparative example. ). Therefore, the cruising range of the traveling motor of the vehicle 12 can be extended.

Further, in the vehicle 12 provided with the vehicle lower structure 10 according to the present embodiment, a traveling motor (not shown) for driving the rear wheels is arranged on the rear side of the vehicle body of the battery pack 30, that is, between the left and right rear wheels 14. can do. That is, the vehicle 12 can be configured to be switchable between front-wheel drive and four-wheel drive. Therefore, the product power can be enhanced as compared with a vehicle that is not configured to be switchable between front-wheel drive and four-wheel drive (only a traveling motor for front-wheel drive can be arranged).

Although the vehicle lower structure 10 according to the present embodiment has been described above with reference to the drawings, the vehicle lower structure 10 according to the present embodiment is not limited to the illustrated one and does not deviate from the gist of the present invention. Within the range, the design can be changed as appropriate. For example, the structure may be such that the recess 34 is not formed on the upper surface of the battery pack 30.

Further, the exhaust pipe 40 is not limited to the configuration in which the exhaust pipe 40 is bent and piped as described above, and may be configured to be curved and piped in an arc shape in a plan view, for example. Further, the exhaust pipe 40 passing through the outside of the fuel tank 20 and the battery pack 30 in the vehicle width direction is not limited to the configuration in which the exhaust pipe 40 is piped so as to pass through the inside of the rocker 16R on the right side in the vehicle width direction. It may be configured to be piped so as to pass through the inside in the vehicle width direction (not shown).

10 Vehicle substructure 12 Vehicle 20 Fuel tank 30 Battery pack (battery)
40 Exhaust pipe 50 Undercover

Claims (1)

A fuel tank located at the bottom of the vehicle on the rear side of the engine and in the center of the vehicle width direction.
A battery that is located on the rear side of the vehicle body of the fuel tank and in the center of the vehicle width direction and is a power source for driving a traveling motor mounted on the vehicle.
An exhaust pipe extending from the engine to the rear side of the vehicle body through the outside of the fuel tank and the battery in the vehicle width direction,
An undercover that covers the lower surface of the fuel tank and the battery,
Vehicle undercarriage with.

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