Vehicle undercarriage

Abstract

To make it possible to minimize an impairment of a vehicle component disposed in a lower part of a vehicle body due to an impact load occurring when a spare tire moves.SOLUTION: A vehicle understructure includes side members 11 disposed on external sides of a floor panel 10. A fuel tank 50 and a spare tire 55 located behind the fuel tank 50 are attached to the undersurface of the floor panel 10 interposed between the side members 11 on the external sides. A restriction member 30 is disposed on the floor panel 10. An intermediate part in a width direction of the restriction member 30 is separated downward from the floor panel 10 with a space between them. The restriction member 30 is interposed between the fuel tank 50 and spare tire 55.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a vehicle undercarriage. [Background technology]

[0002] There is known a vehicle that has a spare tire storage compartment for storing a spare tire in the lower rear portion of the vehicle, as disclosed in Patent Document 1, for example. In this example, the spare tire storage compartment is hinged on the rear surface of the cross member so that it can be opened and closed in the vertical direction, and stores the spare tire while maintaining a predetermined posture.

[0003] Furthermore, vehicle components such as a gasoline tank are located on the vehicle front side of the spare tire. In the above example, a hydrogen tank is located on the vehicle front side of the spare tire storage area. Vehicle components such as the gasoline tank and hydrogen tank need to be protected from damage when the vehicle is subjected to an impact load. Highly rigid components such as a rear frame are located on the vehicle width outer side of these vehicle components to prevent damage to the vehicle components due to an impact load from the vehicle width outer side (impact load due to a side collision).

[0004] In addition, in the above example, when an impact load is received from the rear of the vehicle (for example, an impact load due to a rear-end collision), the amount of intrusion of the spare tire into the front of the vehicle is reduced by having the spare tire abut against the portion of the rear cross member located behind the hydrogen tank that faces the spare tire. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-255663 Summary of the Invention [Problem to be solved by the invention]

[0006] The structure in the above example requires framework members such as a middle floor cross member and a sub-rear frame to support the impact load from the spare tire at the portion facing the spare tire. In other words, this structure forms a transmission path for the collision load by connecting the rear floor cross member and the middle floor cross member with the sub-rear frame.

[0007] The above-described structure requiring rear side frames can ensure rigidity around vehicle components such as hydrogen tanks, but reduces the degree of freedom in the layout of components under the vehicle body. Therefore, the above-described structure leaves room for improvement in terms of increasing the degree of freedom in the layout of components while ensuring rigidity around vehicle components that need to be protected from impact loads.

[0008] The present invention has been made to solve the above-mentioned problems, and its object is to provide a vehicle underbody structure that can reduce damage to vehicle parts arranged under the vehicle body due to impact loads generated by the movement of a spare tire. [Means for solving the problem]

[0009] In order to achieve the above object, the vehicle undercarriage structure of the present invention includes a floor panel that constitutes a vehicle body floor portion, and a pair of side members that are provided on both vehicle widthwise outer sides of the floor panel and extend in the vehicle front-rear direction, and a vehicle component and a spare tire that is located on the vehicle rear side of the vehicle component are attached to the underside of the floor panel located between the side members on both sides. the vehicle component is a fuel tank, a hydrogen tank, a CNG tank, or a battery device; A restricting member extending in the vehicle width direction is provided on the lower surface of the floor panel, and a vehicle width direction intermediate portion of the restricting member is disposed on the vehicle lower side with a gap from the lower surface of the floor panel, and the restricting member is disposed between the vehicle component and the spare tire in the vehicle front-rear direction. and arranged at a distance from the vehicle rear side of the vehicle component. are. [Effects of the Invention]

[0010] According to the present invention, damage to vehicle components arranged under the vehicle body due to impact loads generated by the movement of the spare tire can be reduced. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a bottom view showing an embodiment of a vehicle underbody structure according to the present invention; [Figure 2] FIG. 2 is a bottom view showing a state in which the rear suspension of FIG. 1 has been removed. [Figure 3] FIG. 3 is a perspective view showing a state in which the fuel tank and the like in FIG. 2 have been removed. [Figure 4] 4 is a front view of the restricting member and the spare tire of FIG. 3 as viewed from the front of the vehicle. [Figure 5] FIG. 3 is an enlarged bottom view showing the brace and other components on the left side of FIG. 2. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, one embodiment of a vehicle undercarriage structure for a vehicle according to the present invention will be described with reference to the drawings (Figs. 1 to 5). In the drawings, the direction of arrow Fr indicates the front in the longitudinal direction of the vehicle. In the description of the embodiment, the "front (front end) and rear (rear end)" correspond to the front and rear in the longitudinal direction of the vehicle. Furthermore, arrows R and L indicate the right and left sides when an occupant looks forward of the vehicle. Furthermore, arrow D indicates the underside of the vehicle.

[0013] As shown in FIGS. 1 to 3 , the vehicle undercarriage of this embodiment comprises a floor panel 10 made of a metal material that constitutes a vehicle body floor, and a pair of side members 11 that are provided on both vehicle widthwise outer sides of the floor panel 10 and extend in the vehicle front-rear direction. The floor panel 10 is a plate-shaped member made of a metal material. The vehicle undercarriage also comprises a first cross member 25, a second cross member 28, and a brace 20. A fuel tank 50 (vehicle component) and a spare tire 55 are attached to the underside of the floor panel 10, which is located between the side members 11 on both sides. A restricting member 30 that restricts movement of the spare tire 55 is also provided on the underside of the floor panel 10. The spare tire 55 is located at a distance from the fuel tank 50 and to the vehicle rear.

[0014] 1, a rear suspension 40 is provided on the underside of floor panel 10. A suspension arm 41 extending in the front-to-rear direction of the vehicle is provided on the outer side in the vehicle width direction of rear suspension 40. A rear bumper 65 extending in the vehicle width direction is also provided at the rear end of floor panel 10.

[0015] The pair of side members 11 are highly rigid components that constitute the vehicle body frame and are made of metal. The side members 11 are provided on the outer sides of the floor panel 10 in the vehicle width direction and extend in the vehicle front-rear direction. The side members 11 have a U-shaped cross section that opens toward the top of the vehicle. A flange is provided at the edge of the opening, and the flange is joined to the underside of the floor panel 10 by spot welding or the like.

[0016] Further, a suspension support portion 12 that supports a suspension arm 41 is provided on the underside of the side member 11. A suspension spring and the like (not shown) are disposed on the suspension arm 41 corresponding to the suspension support portion 12. An arm mounting bracket 15 to which the front portion of the suspension arm 41 is rotatably mounted is provided on the vehicle front side of the suspension support portion 12 on the underside of the side member 11.

[0017] The first cross member 25 is a metal member extending in the vehicle width direction, and, like the side members 11, is a highly rigid member that constitutes the vehicle body frame. The first cross member 25 has a U-shaped cross section, and a flange is provided at the opening edge, and the flange is joined to the underside of the floor panel 10 by spot welding or the like. The vehicle width direction end of the first cross member 25 is joined to the side member 11. The vehicle width direction end of the first cross member 25 is located between the suspension support part 12 and the arm mounting bracket 15 in the vehicle fore-and-aft direction. In addition, the main body of the rear suspension 40 is located below the first cross member 25.

[0018] In addition, a bracket for fixing the rear of the fuel tank 50 is provided at the front of the first cross member 25. In this example, a right tank fixing bracket 26a and a left tank fixing bracket 26b are arranged at a distance from each other in the vehicle width direction and are joined to the front of the first cross member 25 and the floor panel 10.

[0019] The second cross member 28 is a metal member extending in the vehicle width direction and, like the first cross member 25, is a highly rigid member that constitutes the vehicle body frame. The second cross member 28 is disposed at a distance from the first cross member 25 toward the rear of the vehicle, and, like the first cross member 25, is joined to the underside of the floor panel 10. A tire mounting portion 60 that accommodates a spare tire 55 is provided on the vehicle lower side of the second cross member 28. The spare tire 55 is attached in a horizontal position to the underside of the floor panel 10 via the tire mounting portion 60. The tire mounting portion will be described later.

[0020] Next, the brace 20 will be described. The brace 20 is provided on the vehicle lower side of the floor panel 10 and is joined to the first cross member 25 and the side member 11. The brace 20 in this example is a highly rigid member made of a metal material, and extends so as to incline outward in the vehicle width direction as it approaches the rear of the vehicle. A restricting member 30, which will be described later, is joined to the brace 20. The brace 20 will be described in detail below.

[0021] As shown in Fig. 5, the front end of brace 20 extends in the vehicle width direction, and a lower flange 21c that protrudes forward of the vehicle and extends in the vehicle width direction is provided at the lower end of the front end. Lower flange 21c is joined by spot welding or the like to the underside of first cross member 25. In addition, tank fixing brackets 26a and 26b are arranged on the vehicle front side of the front end of brace 20 via first cross member 25 (Fig. 1).

[0022] The outer end of the brace 20 in the vehicle width direction extends in the front-rear direction of the vehicle along the side member 11. Although not shown in the drawings, vertical flanges 21d extending in the vehicle up-down direction are provided in front and behind the outer end, and the vertical flanges 21d are joined to the inner part of the side member 11 in the vehicle width direction by spot welding or the like.

[0023] The rear portion of the brace 20 has a rear wall surface that protrudes downward from the underside of the floor panel 10, and this wall surface extends inward in the vehicle width direction from the rear end at the outer end of the brace 20 in the vehicle width direction, curves toward the front of the vehicle, and extends so as to slope toward the front of the vehicle as it extends inward in the vehicle width direction, and is connected to the inner portion of the front end of the brace 20 in the vehicle width direction. A rear flange 21b is provided at the upper end of the rear portion of the brace 20. The rear flange 21b protrudes toward the rear of the vehicle and extends in accordance with the sloped shape of the rear wall surface. The rear flange 21b is joined to the underside of the floor panel 10 by spot welding or the like.

[0024] Furthermore, the vehicle width direction outer portion at the front portion of the brace 20 has an L-shaped wall surface 20a that protrudes downward from the underside of the floor panel 10, and the L-shaped wall surface 20a is formed in an L shape when viewed from above the vehicle. The L-shaped wall surface 20a extends inward in the vehicle width direction from the front end of the vehicle width direction outer end of the brace 20, curves toward the front of the vehicle, extends toward the front of the vehicle, and is connected to the vehicle width direction outer portion at the front end of the brace 20. An outer flange 21a corresponding to the L shape is provided at the upper end of the L-shaped wall surface 20a. The outer flange 21a is joined to the floor panel 10 by spot welding or the like. The L-shaped side surface 20a is disposed opposite a corner 11a formed by the vehicle width direction outer portion of the first cross member 25 and the vehicle width direction inner portion of the side member 11.

[0025] Next, the restricting member 30 will be described. The restricting member 30 is a member that extends in the vehicle width direction as a whole, and in this example, is formed by curving both sides of a hollow member that extends in the vehicle width direction. A vehicle width direction intermediate portion of the restricting member 30 is disposed on the vehicle lower side with a gap between it and the underside of the floor panel 10, and a vehicle width direction outer portion of the restricting member 30 is joined to the vehicle body floor portion. The restricting member 30 is also disposed between the fuel tank 50 and the spare tire 55 in the vehicle front-rear direction, and more specifically, between the first cross member 25 and the spare tire 55.

[0026] A downward extending portion 32 and a curved portion 33 are provided on the outer side of the restricting member 30 in the vehicle width direction. The downward extending portion 32 is joined to the lower surface of the brace 20 and extends from the lower surface of the brace 20 downwardly of the vehicle. The curved portion 33 is formed such that the lower portion of the downward extending portion 32 curves inward in the vehicle width direction. The downward extending portion 32 is joined to the lower surface of the brace 20 via a fixing member 37. The lower portion of the downward extending portion 32 is joined to the fixing member 37 by welding or the like. The fixing member 37 is also fastened to the lower surface of the brace 20 with a bolt. The downward extending portion 32 of the restricting member 30 in this embodiment is joined to the side member 11 and the first cross member 25 via the brace 20.

[0027] The restricting member 30 of this embodiment and the spare tire 55 are disposed with a gap between them in the vehicle longitudinal direction. The restricting member 30 of this embodiment is formed by bending a member into a pipe shape with a circular cross section. The diameter of the restricting member 30 is set to be larger than the diameter of a support member 61, which will be described later.

[0028] As described above, the regulating member 30 is joined to the rear floor panel 10 with a gap therebetween and is positioned between the spare tire 55 and the fuel tank 50, so that the regulating member 30 can prevent the spare tire 55 from flying out toward the front of the vehicle and colliding with the fuel tank 50 when an impact load due to a rear-end collision or the like is applied.

[0029] For example, if an attempt were made to restrict the movement of spare tire 55 by deforming a portion of first cross member 25 to provide a portion facing spare tire 55, the first cross member 25 would need to ensure rigidity as a vehicle body frame member, which could restrict the shape of the facing portion and result in reduced freedom in component layout. In contrast, the restricting member 30 of this embodiment is a pipe-shaped member and is provided at a distance from floor panel 10, so the restricting member 30 does not need to be larger than necessary, improving freedom in component layout.

[0030] Furthermore, in this embodiment, the restricting member 30 is joined to the brace 20, which is joined to the first cross member 25 and the side member 11, which are body frame members. This allows the load from the spare tire 55 input to the restricting member 30 to be transmitted to the first cross member 25 and the side member 11. This improves the rigidity of the joint between the restricting member 30 and the brace 20 and the joint between the brace 20 and the fixing member 37 (in this example, the bolt fastening portion of the fixing member 37). Furthermore, the brace 20, which is smaller in volume than the body frame members, has a high degree of freedom in shape, thereby improving the degree of freedom in layout. Furthermore, in this embodiment, the restricting member 30 is also joined to the floor panel 10 via the brace 20, allowing the load to be distributed over a wider area. Furthermore, joining the restricting member 30 between the left and right braces 20 allows the width of the restricting member 30 to be shortened, thereby improving the rigidity of the restricting member 30 in the front-rear direction. As a result, even if the spare tire 55 comes into contact with the restricting member 30 during a rear-end collision, the restricting member 30 can restrict the spare tire 55 from moving forward.

[0031] Furthermore, because the brace 20 is joined to the side member 11 and the first cross member 25 while spanning the rear of the corner 11a, when the spare tire 55 collides with the restricting member 30, it can be supported by the highly rigid corner 11a formed by the side member 11 and the first cross member 25. As shown in FIG. 5 , the outer end of the brace 20 in the vehicle width direction is joined to the side member 11 at a position corresponding to the suspension support part 12, so that the load transmitted to the brace 20 can be transmitted to a highly rigid part of the side member 11.

[0032] Furthermore, by providing the downward extension portion 32 and the curved portion 33 on the outer side of the regulating member 30 in the vehicle width direction, the area of ​​the spare tire 55 that the regulating member 30 comes into contact with is wider when the spare tire 55 flies out in front of the vehicle, which promotes impact absorption by the regulating member 30 and further enhances the effect of reducing damage to the fuel tank 50.

[0033] Furthermore, in this embodiment, the vehicle width direction intermediate portion of the regulating member 30 has a downward convex shape (convex shape) 31 that is convex toward the floor panel 10. In this example, the vehicle width direction intermediate portion of the regulating member 30 is formed so as to be convex toward the front of the vehicle as well. By providing the downward convex shape 31, the contact area between the rear portion of the regulating member 30 and the spare tire 55 is increased, making it easier to withstand the load from the spare tire 55, further suppressing collision of the spare tire 55 with the fuel tank 50 and further enhancing the effect of reducing damage to the fuel tank 50.

[0034] Furthermore, in this embodiment, the vehicle width direction intermediate portion of the regulating member 30 is slightly convex toward the front of the vehicle, which corresponds to the outer shape (circular shape) of the spare tire 55, and the spare tire 55 can be guided to the portion that convex toward the front, making it possible to control the direction in which the spare tire 55 abuts against the regulating member 30. Furthermore, since the regulating member 30 is disposed at a distance toward the front of the vehicle from the spare tire 55, the spare tire 55 is more likely to abut against the portion that convex toward the front. As a result, when the spare tire 55 moves toward the front of the vehicle, the regulating member 30 can more easily receive the spare tire 55.

[0035] Next, the tire mounting portion 60 will be described. It is provided on the vehicle lower side of the floor panel 10 of this embodiment, and as shown in FIGS. 1 to 3, the tire mounting portion 60 has a support member 61 and an auxiliary member 62. The support member 61 is U-shaped in a top view, opening toward the front of the vehicle, and the front ends of the U-shape on both sides in the vehicle width direction are curved upward toward the vehicle and are rotatably connected to the rotating portion 34 of the restricting member 30, which will be described later. The rear end of the U-shape is curved upward toward the vehicle so as to support the rear portion of the spare tire 55.

[0036] In addition, the auxiliary member 62 is a member that is joined to the middle part of the support member 61 in the vehicle's fore-and-aft direction and extends in the vehicle width direction, and both sides in the vehicle width direction are curved upward of the vehicle so as to support the sides of the spare tire 55.

[0037] The restricting member 30 is provided with two rotating parts 34 arranged at an interval from each other. These rotating parts 34 have shafts (not shown) extending in the vehicle width direction, and the front part of the support member 61 is configured to be rotatable around the shafts of the rotating parts 34.

[0038] As the support member 61 rotates, the rear portion of the support member 61 moves downwards on the vehicle, and after the spare tire 55 is placed on the support member 61 and the auxiliary member 62, the rear portion of the support member 61 moves upwards on the vehicle, and the spare tire 55 is attached by having an engaging portion 63 that engages the rear portion of the support member 61 with the underside of the vehicle body. The spare tire 55 is rotatable so that the rear portion of the spare tire 55 moves downwards on the vehicle while supported by the support member 61 and the auxiliary member 62.

[0039] 4, in this embodiment, when the spare tire 55 is supported by the support members 61 and the auxiliary members 62 and attached to the tire mounting portion 60, the intermediate portion of the regulating member 30 in the vehicle width direction is disposed between the upper and lower ends of the spare tire 55. Thus, by supporting the spare tire 55 with the support members 61, the angle of the spare tire 55 in the event of a collision can be adjusted, and by setting the positional relationship between the regulating member 30 and the spare tire 55 within the above range, it is possible to control the load transmitted to the spare tire 55 so that most of it is input to the regulating member 30.

[0040] The description of the present embodiment is merely an example for explaining the present invention, and does not limit the invention described in the claims. Furthermore, the configuration of each part of the present invention is not limited to the above embodiment, and various modifications are possible within the technical scope described in the claims.

[0041] In this embodiment, the restricting member 30 is joined to the brace 20, but this is not limiting. In this example, one end of the restricting member 30 may be joined to the side member 11 closer to the spare tire 55. The restricting member 30 may also be joined to the floor panel 10 or the first cross member 25. In this embodiment, the vehicle component located on the vehicle front side of the spare tire 55 is the fuel tank 50, but this is not limiting. For example, the vehicle component may be a tank filled with hydrogen, CNG, or the like, or a battery. [Explanation of symbols]

[0042] 10 Floor Panel 11 Side member 11a Corner 12 Suspension support 15 Arm mounting bracket 20 braces 20a L-shaped wall 21a Outer flange 21b Rear flange 21c Lower flange 21d Vertical flange 25 First cross member 26a Right side tank fixing bracket 26b Left tank fixing bracket 28 Second cross member 2 30 Regulatory components 31 downward convex shape (convex shape) 32 Downward extension part 33 Curved section 34 Rotating part 37 Fixing member 40 rear suspension 41 Suspension arm 50 Fuel tank (vehicle part) 55 spare tire 60 Tire mounting part 61 Support member 62 Auxiliary parts 63 Locking part 65 rear bumper

Claims

1. a floor panel constituting a vehicle body floor portion; and a pair of side members provided on both outer sides of the floor panel in the vehicle width direction and extending in the vehicle front-rear direction, A vehicle underbody structure, in which a vehicle component and a spare tire disposed on the vehicle rear side of the vehicle component are attached to a lower surface of the floor panel located between the side members on both sides, the vehicle component is a fuel tank, a hydrogen tank, a CNG tank, or a battery device; A restricting member extending in the vehicle width direction is provided on the lower surface of the floor panel, a vehicle width direction intermediate portion of the restricting member is disposed on a vehicle lower side with a gap therebetween with respect to the lower surface of the floor panel, The vehicle undercarriage structure, characterized in that the restricting member is arranged between the vehicle component and the spare tire in the vehicle fore-and-aft direction, and is arranged on the vehicle rear side of the vehicle component with a gap therebetween.

2. A cross member extending in the vehicle width direction is joined to the lower surface of the floor panel, A brace is provided on the vehicle lower side of the floor panel and is joined to the cross member and the side member, The vehicle underbody structure according to claim 1, wherein the restricting member is joined to the brace.

3. The outer portion of the cross member in the vehicle width direction is joined to the side member, 3. The vehicle underbody structure according to claim 2, wherein the brace is disposed so as to straddle a corner formed by the cross member and the side member.

4. A vehicle comprising: a floor panel constituting a vehicle body floor portion; and a pair of side members provided on both outer sides of the floor panel in the vehicle width direction and extending in the vehicle front-rear direction; A vehicle underbody structure, in which a vehicle component and a spare tire disposed on the vehicle rear side of the vehicle component are attached to a lower surface of the floor panel located between the side members on both sides, A restricting member extending in the vehicle width direction is provided on the lower surface of the floor panel, a vehicle width direction intermediate portion of the restricting member is disposed on a vehicle lower side with a gap therebetween with respect to the lower surface of the floor panel, the restricting member is disposed between the vehicle component and the spare tire in the vehicle front-rear direction, A cross member extending in the vehicle width direction is joined to the lower surface of the floor panel, A brace is provided on the vehicle lower side of the floor panel and is joined to the cross member and the side member, the restricting member is joined to the brace, A vehicle undercarriage structure characterized in that a downward extension portion extending from the brace toward the bottom of the vehicle is provided on the vehicle width direction outer side of the regulating member, and a curved portion curved toward the inside of the vehicle is provided at the bottom of the downward extension portion.

5. A vehicle comprising: a floor panel constituting a vehicle body floor portion; and a pair of side members provided on both outer sides of the floor panel in the vehicle width direction and extending in the vehicle front-rear direction, A vehicle underbody structure, in which a vehicle component and a spare tire disposed on the vehicle rear side of the vehicle component are attached to a lower surface of the floor panel located between the side members on both sides, A restricting member extending in the vehicle width direction is provided on the lower surface of the floor panel, a vehicle width direction intermediate portion of the restricting member is disposed on a vehicle lower side with a gap therebetween with respect to the lower surface of the floor panel, the restricting member is disposed between the vehicle component and the spare tire in the vehicle front-rear direction, A vehicle undercarriage structure, wherein a vehicle width direction intermediate portion of the restricting member has a convex shape that is convex toward the floor panel.

6. A vehicle comprising: a floor panel constituting a vehicle body floor portion; and a pair of side members provided on both outer sides of the floor panel in the vehicle width direction and extending in the vehicle front-rear direction, A vehicle underbody structure, in which a vehicle component and a spare tire disposed on the vehicle rear side of the vehicle component are attached to a lower surface of the floor panel located between the side members on both sides, A restricting member extending in the vehicle width direction is provided on the lower surface of the floor panel, a vehicle width direction intermediate portion of the restricting member is disposed on a vehicle lower side with a gap therebetween with respect to the lower surface of the floor panel, the restricting member is disposed between the vehicle component and the spare tire in the vehicle front-rear direction, The spare tire is supported by a support member extending in the front-rear direction of the vehicle, The restricting member is provided with a rotating portion to which a front portion of the support member is attached so as to be rotatable around an axis extending in the vehicle width direction, a vehicle lower structure, wherein when the spare tire is attached to the support member, a vehicle width direction intermediate portion of the restricting member is disposed between an upper end and a lower end of the spare tire.

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