JP2005059609A - Hood structure for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve shock absorbing efficiency without increasing the number of parts. <P>SOLUTION: Three pieces of relieves 20, 22, 24 are formed along the car body longitudinal direction on a front half part 12A of an outer panel 12 of a hood 10, and intervals between each of the relives 20, 22, 24 are respectively set less than 400 mm. Additionally, length of each of the relieves 20, 22, 24 along the car body longitudinal direction is respectively set less than 600 mm in rectilinear distance. Additionally, each of the relieves 20, 22, 24 is made in a recessed shape recessed downward on a car body, and width of each of the recessed shapes is respectively set less than 50 mm. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hood structure for a vehicle, and more particularly to a hood structure for a vehicle that protects a collision body at the time of a collision in a vehicle such as an automobile.
[0002]
[Prior art]
Conventionally, in a vehicle hood structure such as an automobile, an inner panel is provided on the back surface of an outer panel having a convex flat part and a concave flat part partitioned by a step part, and an inner panel is provided between the outer panel and the inner panel. The structure which suppresses the inversion behavior of a level | step-difference part and improves the impact absorption efficiency is provided by providing the impact-absorbing body supported by the back and supporting the level | step-difference part vicinity of a convex side plane part from the back surface (for example, patent document 1) reference).
[0003]
[Patent Document 1]
Japanese Patent No. 3329086 [0004]
[Problems to be solved by the invention]
However, in the vehicle hood structure disclosed in Patent Document 1, when the colliding body collides with the stepped portion of the outer panel, when the deformation of the stepped portion becomes a predetermined size, the shock absorber is crushed and deformed to generate a desired reaction force. It has come to occur. As a result, it is necessary to add a shock absorber to the conventional hood, resulting in an increase in the number of parts.
[0005]
In view of the above facts, an object of the present invention is to provide a vehicle hood structure capable of improving the impact absorption efficiency without increasing the number of parts.
[0006]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a vehicle hood structure having an outer panel in which a relief is formed with a length of 600 mm or less in a longitudinal direction of the vehicle body.
[0007]
Accordingly, the main influence range of the outer panel with respect to the initial acceleration of the collision object is often 600 mm or less with the striking position (collision center) as the center. As a result, by setting the length of the relief along the longitudinal direction of the vehicle body to 600 mm or less, the relief can be completely placed in a circular region having a diameter of 600 mm or less centered on the hitting position. A step difference from the outside of the circular area can be eliminated. For this reason, it can suppress that initial acceleration falls, when a colliding body collides with an outer panel. In addition, since a separate shock absorbing member is not used, the shock absorbing efficiency can be improved without increasing the number of parts.
[0008]
According to a second aspect of the present invention, in the hood structure for a vehicle according to the first aspect, two or more reliefs are formed in the front half of the outer panel along the vehicle front-rear direction at intervals of 400 mm or less in the front half of the outer panel. It is characterized by being.
[0009]
Therefore, in addition to the contents described in claim 1, the outer panel of the hood has a yield point when the outer panel of the hood is pressed during vehicle cleaning or the like (referred to as a static yield point), and the collision object during traveling at a speed higher than a predetermined value. If it is made of a material such as iron that has a different yield point (called dynamic yield point) in the event of a collision, the relief is placed in the front half of the outer panel at intervals of 400 mm or less in the vehicle width direction. By forming two or more along the direction, the dynamic yield point in the front half of the outer panel can be lowered. As a result, at the front half of the outer panel where the light top of a small collision body that is relatively easy to collide with the front of the hood collides, a predetermined rigidity is secured against the pressing force during cleaning, etc. based on the static yield point. However, it is possible to reduce the initial load generated when the collision object collides based on the dynamic yield point lowered by the relief. For this reason, it can prevent that a big impact acts on a collision body.
[0010]
On the other hand, since the relief is not formed in the rear half of the outer panel where the heavy top of a large collision body that collides relatively easily with the rear of the hood collides, the dynamic yield point is high. For this reason, reduction of the generated load at the time of collision with a collision object can be prevented, and impact absorption efficiency can be improved.
[0011]
In addition, since a separate shock absorbing member is not used, the shock absorbing efficiency can be improved without increasing the number of parts.
[0012]
According to a third aspect of the present invention, in the vehicular hood structure according to the first or second aspect, the relief has a concave shape recessed downward in the vehicle body, and the width of the concave shape is 50 mm. It is characterized as follows.
[0013]
Therefore, in addition to the content described in any one of claims 1 and 2, when the collision body is a pedestrian, the radius of the top is about 65 mm to 82 mm, so that the relief having a concave shape is used. By making the width of 50 mm or less, the contact portion between the top of the collision body and the outer panel can straddle the concave relief when the outer panel is deformed. As a result, a tensile load can be generated at both ends of the relief in the outer panel when the outer panel is deformed. For this reason, the initial collision load can be increased.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a vehicle hood structure in the present invention will be described with reference to FIGS.
[0015]
In the figure, the arrow UP indicates the upward direction of the vehicle body, and the arrow FR in the figure indicates the forward direction of the vehicle body.
[0016]
As shown in FIG. 3, in the present embodiment, the front half 12A of the outer panel 12 that constitutes the vehicle body outer surface of the hood 10 of the automobile is provided with a step portion as viewed from the three vehicle longitudinal directions along the vehicle longitudinal direction. The reliefs 20, 22, 24 thus formed are continuously formed.
[0017]
In addition, one relief 20 is formed at the center of the outer panel 12 in the vehicle width direction, and the other two reliefs 22 and reliefs 24 are formed outside the relief 20 in the vehicle width direction and in parallel with the relief 20. Has been.
[0018]
As shown in FIG. 1, the distance S1 between the relief 20 and the relief 22 in the vehicle width direction and the distance S2 between the relief 20 and the relief 24 in the vehicle width direction are set to 600 mm or less, preferably 400 mm or less, respectively.
[0019]
The length L1 of the relief 20 along the longitudinal direction of the vehicle body, the length L2 of the relief 22 along the longitudinal direction of the vehicle body, and the length L3 of the relief 24 along the longitudinal direction of the vehicle body are each set to a linear distance of 600 mm or less. Yes.
[0020]
As shown in FIG. 2, each of the reliefs 20, 22, and 24 has a concave shape that is recessed downward of the vehicle body, and the widths W1, W2, and W3 of each concave shape are set to 50 mm or less.
[0021]
Next, the operation of this embodiment will be described.
[0022]
The yield point when the outer panel 12 of the hood 10 is pressed during vehicle cleaning (referred to as a static yield point) and the yield point when a collision object collides during traveling at a speed equal to or higher than a predetermined value (dynamic yield point) In the case of being made of a material such as iron that is different from that of the point), reliefs 20, 22, and 24 are arranged at intervals of 400 mm or less in the vehicle width direction at the front half 12A of the outer panel 12 as in the present embodiment. By forming two or more along the longitudinal direction of the vehicle body at S1 and S2, the dynamic yield point at the front half 12A of the outer panel 12 can be lowered.
[0023]
As a result, in the portion of the front half 12A of the outer panel 12 where the light top of a small collision body that is relatively easy to collide with the front of the hood collides, a predetermined static force is applied to the pressing force during cleaning based on a high static yield point. The generated load at the time of collision with the collision object can be reduced based on the lowered dynamic yield point while ensuring the rigidity. For this reason, it can prevent that a big impact acts on the top part of a small collision object.
[0024]
On the other hand, since the reliefs 20, 22, and 24 are not formed in the rear half of the outer panel 12 where the heavy top of a large collision body that is relatively easy to collide with the rear of the hood collides, the dynamic yield point is high. For this reason, when the top part of a large-sized collision body collides, reduction of an initial generation load can be prevented and impact absorption efficiency can be improved.
[0025]
Further, in the present embodiment, since the shock absorbing member which is a separate member is not used, the shock absorbing efficiency can be improved without increasing the number of parts and the weight.
[0026]
Further, the main influence range of the outer panel 12 with respect to the initial acceleration of the collision object often has a diameter of 600 mm or less around the hitting position (collision center). As a result, by setting the lengths L1, L2, and L3 of the reliefs 20, 22, and 24 along the longitudinal direction of the vehicle body to 600 mm or less, as shown in FIG. The reliefs 20, 22, 24 can be completely placed in the region R. For this reason, the step between the circular region R and the outside of the circular region can be eliminated.
[0027]
Therefore, in this embodiment, when an impact body collides with the outer panel 12, it can suppress that an initial acceleration falls.
[0028]
In addition, when the collision body is a pedestrian, the radius of the top is about 65 mm to 82 mm, and therefore the widths W1, W2, and W3 of the concave reliefs 20, 22, and 24 should be 50 mm or less. Thus, as shown in FIG. 2, when the outer panel is deformed, the contact portions P <b> 1 and P <b> 2 between the collision member top portion S and the outer panel 12 can straddle the concave reliefs 20, 22, and 24.
[0029]
As a result, a tensile load can be generated at both ends of the reliefs 20, 22, 24 in the outer panel 12 when the outer panel is deformed. For this reason, the initial collision load can be increased.
[0030]
Further, since the reliefs 20, 22, and 24 are concave, the lateral acceleration G <b> 1 that acts on the collision body S becomes uniform at the contact portions P <b> 1 and P <b> 2 at both ends of the reliefs 20, 22, and 24. As a result, unnecessary post-lateral acceleration can be reduced or eliminated. For this reason, it is possible to leave only the vertical acceleration G2 effective for absorbing the shock.
[0031]
Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art. For example, in the above embodiment, the three reliefs 20, 22, 24 are formed in the front half 12A of the outer panel 12, but the number of reliefs may be two or more, as shown in FIG. The reliefs 26 and 28 may be added outside the reliefs 22 and 24 in the vehicle width direction so that there are five reliefs. Further, as shown in FIG. 4B, a total of two reliefs 30 and 32 are formed from the front inner side of the vehicle body toward the rear outer side of the vehicle body, in the vicinity of both ends in the vehicle width direction of the rear portion 12B of the outer panel 12. You may do it. Note that the length L4 of the relief 30 along the longitudinal direction of the vehicle body and the length L5 of the relief 32 along the longitudinal direction of the vehicle body are each set to 600 mm or less as a linear distance.
[0032]
In this embodiment, the reliefs 20, 22, and 24 are formed in a linear shape that is continuous in the longitudinal direction of the vehicle body. Instead, the reliefs 20, 22, and 24 are intermittently formed in the longitudinal direction of the vehicle body. It is good also as a structure. When the reliefs 20, 22, and 24 are intermittently formed in the longitudinal direction of the vehicle body, load control by the reliefs 20, 22, and 24 is facilitated.
[0033]
Further, in the present embodiment, the reliefs 20, 22, and 24 have a concave shape that is recessed downward in the vehicle body. Instead of this, as shown in FIG. 5, the reliefs 20, 22, and 24 are convex that bulge upward in the vehicle body. It is good also as a shape. In this case, it is easy to secure a gap with a member such as an engine below the hood.
[0034]
Further, as shown in FIG. 6, the relief 20 may have a concave shape that is recessed downward in the vehicle body, and the reliefs 22 and 24 may have a convex shape that bulges upward in the vehicle body.
[0035]
Furthermore, although not shown in the drawings, the reliefs 22 and 24 may have a concave shape that is recessed downward in the vehicle body, and the relief 20 may be a convex shape that swells upward in the vehicle body.
[0036]
【The invention's effect】
Since the vehicle hood structure according to the first aspect of the present invention has an outer panel in which a relief is formed with a length of 600 mm or less in the longitudinal direction of the vehicle body, it is possible to improve the impact absorption efficiency without increasing the number of parts. Have
[0037]
According to a second aspect of the present invention, in the vehicle hood structure according to the first aspect, two or more reliefs are formed in the front half of the outer panel along the front-rear direction of the vehicle body at intervals of 400 mm or less in the front half of the outer panel. Therefore, it has an excellent effect that the impact absorption efficiency can be improved without increasing the number of parts.
[0038]
According to a third aspect of the present invention, in the vehicular hood structure according to the first or second aspect, the relief has a concave shape recessed downward in the vehicle body, and the width of the concave shape is 50 mm or less. Therefore, in addition to the effect described in claim 1 or 2, it has an excellent effect that the initial collision load can be increased.
[Brief description of the drawings]
FIG. 1 is a plan view showing a vehicle hood structure according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along line 2-2 of FIG.
FIG. 3 is a perspective view showing a vehicle hood structure according to an embodiment of the present invention, as viewed obliquely from the front of the vehicle body.
4A is a plan view showing a vehicle hood structure according to a modification of the embodiment of the present invention, and FIG. 4B is a vehicle hood according to another modification of the embodiment of the present invention. It is a top view which shows a structure.
FIG. 5 is a cross-sectional view corresponding to FIG. 2 showing a vehicle hood structure according to a modification of the embodiment of the present invention.
6 is a cross-sectional view corresponding to FIG. 2, showing a vehicle hood structure according to another modification of the embodiment of the present invention.
[Explanation of symbols]
10 Hood 12 Outer panel 20 Hood 20 Relief 22 Relief 24 Relief 26 Relief 28 Relief 30 Relief 32 Relief

Claims (3)

A vehicle hood structure having an outer panel having a relief formed in a length of 600 mm or less in a longitudinal direction of the vehicle body. 2. The hood structure for a vehicle according to claim 1, wherein two or more reliefs are formed in a front half portion of the outer panel along a longitudinal direction of the vehicle body at an interval of 400 mm or less in a vehicle width direction. 3. The vehicle hood structure according to claim 1, wherein the relief has a concave shape recessed downward in the vehicle body, and the width of the concave shape is 50 mm or less. 4.

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