Vehicle under structure

Abstract

The invention provides a vehicle lower structure. The vehicle lower structure includes a plurality of rectifying members disposed on a lower surface of a vehicle body rearward of a rear tire. Each of the plurality of rectifying members has a flat plate shape, protrudes downward from the lower surface of the vehicle body, and extends in the front-rear direction of the vehicle. The plurality of rectifying members are disposed at intervals in the vehicle width direction.

Description

Technical Field

[0001] The present disclosure relates to a vehicle lower structure, and particularly to a vehicle lower structure for improving the handling stability of a vehicle. Background Art

[0002] In vehicles such as automobiles, there is a known technique of providing fins in combination lamps located at the rear of the vehicle, side mirrors located at the front of the vehicle, etc. to improve the handling stability of the vehicle.

[0003] In Japanese Patent Laid-Open No. 2020-29128, a structure in which fins are provided in a side sunshade to improve the handling stability of a vehicle is disclosed. Summary of the Invention

[0004] When fins are provided at a position where the user of the vehicle can easily see, the fins sometimes affect the appearance of the vehicle. A technique for suppressing the influence on the appearance of the vehicle and improving the handling stability of the vehicle is desired.

[0005] An object of the present disclosure is to suppress the influence on the appearance of the vehicle and improve the handling stability of the vehicle.

[0006] The vehicle lower structure of the solution of the present disclosure includes a plurality of fairing members, the fairing members are arranged on the lower surface of the vehicle body behind the rear tires, the plurality of fairing members each have a flat plate shape, protrude downward from the lower surface of the vehicle body and extend in the vehicle front-rear direction, and the plurality of fairing members are arranged at intervals in the vehicle width direction.

[0007] In addition, in the vehicle lower structure of the above solution, it may be that the plurality of fairing members are composed of a first fairing member and a second fairing member, the first fairing member is arranged at a position closer to the inside than the center in the width direction of the rear tire in the vehicle width direction, and the second fairing member is arranged at a position closer to the outside than the first fairing member in the vehicle width direction.

[0008] In addition, in the vehicle lower structure of the above solution, it may be that the second fairing member is arranged at a position closer to the outside than the center in the width direction of the rear tire in the vehicle width direction.

[0009] In addition, in the vehicle lower structure of the above solution, it may be that the length of the first fairing member in the vehicle front-rear direction is longer than the length of the second fairing member in the vehicle front-rear direction.

[0010] In addition, in the vehicle lower structure of the above solution, it is also possible that each of the plurality of rectifying components includes: a front portion having an inclined surface that slopes downward from the front of the vehicle toward the rear of the vehicle; and a rear portion having an inclined surface that slopes upward from the front of the vehicle toward the rear of the vehicle. In each of the plurality of rectifying components, the inclined surface of the front portion is steeper than the inclined surface of the rear portion.

[0011] According to the present disclosure, when the vehicle is running, the wind from the outer side in the width direction of the rear tire and the wind from the inner side thereof are rectified by a plurality of rectifying components disposed behind the rear tire, so that the handling stability of the vehicle can be improved. In addition, since the plurality of rectifying components are disposed on the lower surface of the vehicle body that is difficult for the user to see, the influence of the plurality of rectifying components on the appearance of the vehicle can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Hereinafter, the features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described with reference to the accompanying drawings, in which the same reference numerals denote the same components, where:

[0013] Figure 1 is a side view of the rear of the vehicle;

[0014] Figure 2 is a side view of the rectifying component group of the vehicle;

[0015] Figure 3 is a perspective view of the rear bottom of the vehicle;

[0016] Figure 4 is a perspective view of the rectifying component group of the vehicle;

[0017] Figure 5 is a bottom view of the rectifying component group of the vehicle; and

[0018] Figure 6 is a radar chart showing the effects of the rectifying component group. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the present invention is not limited to the embodiments described herein. In all the drawings, the same reference numerals are assigned to the same elements, and repeated descriptions are omitted. In the following description, unless otherwise specified, the statements indicating directions and orientations such as front, rear, left, right, up, and down indicate the directions and orientations related to the vehicle. In each figure, the direction of the arrow FR indicates the front, the direction of the arrow UP indicates the upper side, and the direction of the arrow RH indicates the right side. In addition, the side closer to the center in the left-right direction (width direction) of the vehicle is referred to as the inner side in the vehicle width direction, and the side farther from the center is referred to as the outer side in the vehicle width direction.

[0020] Figure 1is a side view of the rear part of vehicle 10, showing the right side of vehicle 10. Vehicle 10 is an automobile. Vehicle 10 has two front tires (not shown) and two rear tires 14 (only one is shown in Figure 1 ).

[0021] Vehicle 10 can be an SUV (Sport Utility Vehicle), a wagon, or other automobiles with a relatively high vehicle height and a relatively high center of gravity. Such vehicles are generally disadvantageous in terms of handling stability. However, by adopting the vehicle lower structure 12 described below, the handling stability can be improved. In addition, the vehicle lower structure 12 can also be used for other automobiles such as sedans, thereby improving the handling stability of these automobiles.

[0022] As Figure 1 shown, the vehicle lower structure 12 includes a fairing component group 30 disposed on the lower surface of the vehicle body behind the rear tire 14. The fairing component group 30 is composed of a first fairing component 31 and a second fairing component 32. In Figure 1 , the first fairing component 31 and the second fairing component 32 that appear under the rear bumper 16 are shown. In addition, hereinafter, the fairing component group 30 disposed behind the rear tire 14 on the right side will be described, but the same fairing component group 30 is also disposed behind the left rear tire (not shown). That is, vehicle 10 symmetrically has a pair of fairing component groups 30 on the left and right.

[0023] Figure 2 is Figure 1 a partial enlarged view of the fairing component group 30. In addition, in Figure 2 , the outline of a part of the first fairing component 31 located on the back side of the second fairing component 32 is indicated by a dotted line. Figure 3 is a perspective view of the rear bottom 40 of vehicle 10. Figure 4 is a perspective view of the fairing component group 30 of vehicle 10. In addition, Figure 5 is a bottom view of the fairing component group 30 of vehicle 10.

[0024] As Figure 3 shown, vehicle 10 includes a wheel housing panel 42, a rear bumper 16, and a bottom member 24. The wheel housing panel 42 forms the wheel housing of the rear tire 14. As Figure 4 shown, the rear bumper 16 includes a side portion 18 and an edge portion 20. The edge portion 20 is a portion bent downward from the side portion 18 of the rear bumper 16. In addition, the rear bumper 16 actually has a gradual shape change, that is, a gentle curved surface, between the side portion 18 and the edge portion 20, but in Figures 3 - 5 , this curved surface is omitted and the shape of the rear bumper 16 is simplified.

[0025] The bottom member 24 is, for example, a resin member manufactured by injection molding. As Figure 3 shown, the bottom member 24 includes a bottom plate 26 and a rectifying member group 30. In addition, the bottom member 24 further includes an upper portion (not shown) connected to the bottom plate 26 and disposed on the upper side (inside the vehicle body) of the bottom plate 26, and the upper portion is fixed to a structure (not shown) provided at the rear of the vehicle. As Figure 3 shown, the bottom plate 26 forms a part of the vehicle body bottom surface. The bottom plate 26 is disposed behind the wheel housing panel 42.

[0026] As Figure 4 shown, the bottom plate 26 of the bottom member 24 is disposed above the edge portion 20 of the rear bumper 16. The outer portion in the vehicle width direction of the bottom plate 26 is fixed to the edge portion 20 of the rear bumper 16 by screws 22.

[0027] As Figure 4 shown, the first rectifying member 31 and the second rectifying member 32 are arranged side by side at intervals in the vehicle width direction. The first and second rectifying members 31, 32 respectively project downward from the bottom plate 26. The first and second rectifying members 31, 32 respectively extend in the front-rear direction. That is, the extending directions of the first and second rectifying members 31, 32 are the same as the front-rear direction of the vehicle. The first and second rectifying members 31, 32 respectively have a flat plate shape. The thickness (width in the vehicle width direction) of the first and second rectifying members 31, 32 is constant or substantially constant in the front-rear direction.

[0028] The first rectifying member 31 includes a front portion 31f, a main body portion 31b, and a rear portion 31r. The front portion 31f has an inclined surface 31fs (see Figure 2 ) that slopes downward from the front to the rear. The main body portion 31b has a constant or substantially constant height. The rear portion 31r has an inclined surface 31rs that slopes upward from the front to the rear.

[0029] Similarly, the second rectifying member 32 includes a front portion 32f, a main body portion 32b, and a rear portion 32r. The front portion 32f has an inclined surface 32fs (see Figure 2 ) that slopes downward from the front to the rear. The main body portion 32b has a constant or substantially constant height. The rear portion 32r has an inclined surface 32rs that slopes upward from the front to the rear.

[0030] In each of the first and second rectifying members 31 and 32, the inclined surface 31fs (32fs) of the front portion 31f (32f) is steeper than the inclined surface 31rs (32rs) of the rear portion 31r (32r). The inclined surface 31fs (32fs) of the front portion 31f (32f) is formed to be relatively steep in order to capture wind more quickly when the vehicle is running and cause the wind to flow along the main body portion 31b (32b). The inclined surface 31rs (32rs) of the rear portion 31r (32r) is formed to be relatively gentle in order to allow the wind flowing along the main body portion 31b (32b) to flow smoothly rearward and from an aesthetic point of view.

[0031] As Figure 2 shown, the front end of the second rectifying member 32 is located at a position slightly forward of the front end of the first rectifying member 31. Further, in this embodiment, as Figure 2 shown, the height of the main body portion of the second rectifying member 32 is slightly higher than the height of the main body portion of the first rectifying member 31. Alternatively, it may be configured such that the height of the main body portion of the first rectifying member 31 is the same as the height of the main body portion of the second rectifying member 32.

[0032] Further, in this embodiment, as Figure 5 shown, the first rectifying member 31 is longer in the front-rear direction than the second rectifying member 32. The difference in this length depends on the limitation of the arrangement space. That is, as Figure 5 shown, the rear bumper 16 (the side portion of the vehicle body) is slightly bent inward from the outer side in the vehicle width direction, and thus the length of the second rectifying member 32 in the front-rear direction is limited compared to the first rectifying member 31. Further, in the case where there is no such limitation, for example, in the case where the vehicle body shape behind the rear tire 14 allows the expansion of the length of the second rectifying member 32, the length of the second rectifying member 32 in the front-rear direction may also be the same as or substantially the same as the length of the first rectifying member 31 in the front-rear direction.

[0033] As Figure 5 shown, the first rectifying member 31 is arranged at a position inside the width direction center C of the rear tire 14 in the vehicle width direction. The second rectifying member 32 is arranged at a position outside the first rectifying member 31 in the vehicle width direction. Specifically, the second rectifying member 32 is arranged at a position slightly outside the width direction center C of the rear tire 14 in the vehicle width direction. Further, the interval between the first rectifying member 31 and the second rectifying member 32 is narrower than the width of the rear tire 14.

[0034] Next, the effects of the vehicle lower structure 12 of the above-described embodiment, in which the first and second rectifying members 31 and 32 are respectively provided behind the left and right rear tires 14, will be described.

[0035] When the vehicle 10 is moving forward, as Figure 5 shown, winds W1 to W3 are generated behind the rear tire 14. Wind W1 is the wind that flows outside the width direction of the rear tire 14 through the side of the vehicle and is drawn into the rear of the rear tire 14. Wind W2 is the wind that flows inside the width direction of the rear tire 14 through the bottom surface of the vehicle body and enters the rear of the rear tire 14. Wind W3 is the wind that flows to the rear of the rear tire 14 through the wheel housing of the rear tire 14.

[0036] The flow rates of winds W1 to W3 are different. In particular, the flow rates of winds W1 and W2 are different. If these winds mix, that is, cross, behind the rear tire 14, wind turbulence is generated and the stability of the vehicle 10 decreases.

[0037] However, according to the embodiment described above, by the first and second rectifying members 31 and 32, winds W1 to W3 can be separated and the crossing of these winds can be reduced. That is, as Figure 5 shown, most of wind W1 can flow outside the second rectifying member 32 (outside the vehicle width direction). The second rectifying member 32 inhibits wind W1 from entering the inside of the vehicle width direction behind the rear tire 14. That is, the second rectifying member 32 blocks the entry of wind W1 into the inside of the vehicle width direction. In addition, as Figure 5 shown, most of wind W2 can flow outside the first rectifying member 31 (inside the vehicle width direction). The first rectifying member 31 inhibits wind W2 from advancing outside the vehicle width direction behind the rear tire 14. That is, the first rectifying member 31 blocks the advancement of wind W2 outside the vehicle width direction. In addition, most of wind W3 can flow between the first rectifying member 31 and the second rectifying member 32. Thus, by rectifying the flow of the wind using the first and second rectifying members 31 and 32, the handling stability of the vehicle 10 can be improved.

[0038] According to the embodiment described above, stable straight running can be ensured when the vehicle is running. In addition, during vehicle running, even when the steering wheel is turned (during steering), wind turbulence can be reduced and the vehicle can turn stably.

[0039] In addition, according to the embodiment described above, the first and second rectifying members 31 and 32 are arranged on the lower surface of the vehicle body where the user can hardly see, so the influence of the first and second rectifying members 31 and 32 on the appearance of the vehicle 10 can be suppressed. The handling stability and appearance (design) of the vehicle 10 can be achieved simultaneously.

[0040] Figure 6It is a radar chart showing the effects of the vehicle lower structure 12 (with a rectifying component) described above. After multiple drivers drove a vehicle with fins provided on a conventional rear combination lamp (a combination lamp located at the rear of the vehicle) (hereinafter referred to as a conventional vehicle) and a vehicle 10 adopting the vehicle lower structure 12 of the present embodiment (hereinafter referred to as the vehicle of the present invention), they evaluated 12 items related to handling stability. In addition, of course, the rectifying component described above is not provided in the conventional vehicle, and the fins of the conventional rear combination lamp are not provided in the vehicle of the present invention. Moreover, for each item, a representative value presented by the evaluation results of multiple drivers was obtained and plotted as a radar chart. Thus, in Figure 6 the evaluation results of the vehicle of the present invention (with a rectifying component) based on the conventional vehicle are shown.

[0041] As Figure 6 shown, it was confirmed that for the vehicle 10 of the present invention, that is, the vehicle provided with the first and second rectifying components 31 and 32, handling stability equal to or higher than the reference (conventional vehicle) can be ensured. In particular, it was confirmed that by providing the first rectifying component 31 and the second rectifying component 32, the "sense of stability (when going straight)", the "goodness of yaw response (near N)", and the "post-transition grip feeling" were improved compared to the reference (the fins of the rear combination lamp).

[0042] In addition, the "sense of stability (when going straight)" is the stability of the vehicle when going straight, which means that there is little lateral shaking when driving straight. In addition, the "goodness of yaw response (near N)" is the responsiveness of the steering wheel when the vehicle is driving, which is the goodness of the vehicle's reaction when the steering wheel is made straight (N) and then slightly turned. In addition, the "post-transition grip feeling" is the grip feeling of the rear part of the vehicle when the vehicle makes a sharp lane change while driving, which means that the grounding and stability of the rear tires are felt when the vehicle makes a sharp lane change.

[0043] Based on the above, it can be understood that the vehicle lower structure 12 of the present embodiment is an excellent structure from the viewpoint of handling stability.

[0044] In addition, in the embodiment described above, the rectifying component group 30 is composed of two rectifying components (the first and second rectifying components 31 and 32). However, the rectifying component group 30 may also be composed of three or more rectifying components.

Claims

1. A vehicle lower structure, wherein: The vehicle lower structure includes a plurality of fairing members, the fairing members being arranged on the lower surface of the vehicle body behind the rear tires. The plurality of fairing members each have a flat plate shape, protrude downward from the lower surface of the vehicle body and extend in the front-rear direction of the vehicle. The plurality of air flow regulating members are arranged at intervals in the vehicle width direction.

2. The vehicle lower structure according to claim 1, wherein: The plurality of rectifying components are composed of a first rectifying component and a second rectifying component, The first fairing member is arranged inwardly of the width center of the rear tire in the vehicle width direction. The second air flow regulating member is disposed on an outer side of the first air flow regulating member in the vehicle width direction.

3. The vehicle lower structure according to claim 2, wherein: The second fairing member is disposed on the outside of a widthwise center of the rear tire in the vehicle width direction.

4. The vehicle lower structure according to claim 2 or 3, wherein: The length of the first fairing member in the vehicle front-rear direction is longer than the length of the second fairing member in the vehicle front-rear direction.

5. The vehicle lower structure according to any one of claims 1 to 3, wherein: The plurality of fairing members each include: a front portion having an inclined surface that is inclined downward from the front of the vehicle toward the rear of the vehicle; and a rear portion having an inclined surface that is inclined upward from the front of the vehicle toward the rear of the vehicle. In each of the plurality of the straightening members, the inclined surface of the front portion is steeper than the inclined surface of the rear portion.

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