JPH09249157A - Car body hood structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the rigidity in the intermediate and later stage while maintaining the rigidity in the initial stage of a hood inner panel and absorb the shock energy transferred to the hood inner panel from a hood outer panel at the time of a collision with a car body hood. SOLUTION: A hood inner panel 2 is formed with the front and rear vertical walls, a flat wall at the center, and flanges 4 continued at the upper ends of the vertical walls, and slits 5 are formed in the vertical direction on the rear vertical wall 2R. The flange 4 of the vertical wall 2R is faced to the hood outer panel 1 at an interval without being connected to the hood outer panel 1, and only the flange 4 of the front vertical wall is connected to the hood outer panel 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hood structure that controls the deceleration of a head impactor when a vehicle body hood collides.

[0002]

2. Description of the Related Art As a conventional vehicle body hood structure, for example, there is a structure as shown in FIGS.
(See No. 054590). This conventional structure has a hood outer panel (hereinafter referred to as a hood outer).
Flange 104, 104 for connecting a hood inner panel (hereinafter, referred to as a hood inner) 102 joined to 101
In addition, in order to increase the rigidity of the entire hood, a convex bead 105 is arranged on the outer side of the hood.

[0003]

However, in such a conventional vehicle body hood structure, the hood inner 102 has a generally rectangular cross section and is continuous with the vertical wall extending toward the hood outer 101. Since the structure is joined to the hood outer 101 at 104, FIG.
As shown in FIG. 3, when an obstacle such as an animal collides with the hood and the hood inner 102 deforms due to contact with the engine 103 or the like, the buckling deformation of the vertical wall of the hood inner 102 becomes a bending mode and the crushing remains. May occur.
Although the energy is absorbed even in the state where the uncrushed portion remains, the height of the hood inner 102 is reduced because it is difficult to reduce the post-half-speed generated in an obstacle such as an animal and it is difficult to form an effective energy absorption structure. There were problems that it could not be lowered, the degree of freedom in design was narrowed, and the weight could not be reduced.

The present invention has been made by paying attention to such conventional problems, and in the body hood structure,
In order to absorb the impact energy transmitted from the hood outer and ensure the initial rigidity, the front vertical wall that supports the flat wall that serves as the bottom is joined to the outer panel, and the rear vertical wall has slits and is alternately joined to the hood outer. However, the other flange has a structure such as having a predetermined gap, and aims to solve the above problems by reducing the rigidity in the middle and late stages while maintaining the initial rigidity.

[0005]

[Means for Solving the Problems] In order to achieve the above-mentioned object, in the invention according to claim 1, a plurality of substantially rectangular hollow cross-sections that connect the hood outer panel and the hood inner panel and are continuous in the vehicle width direction are provided. In the car body hood structure,
The hood inner panel is formed by front and rear vertical walls, a central flat wall, a flange continuous to the upper end of the vertical wall, and a vertical slit in at least one of the front and rear vertical walls of the hood inner panel. The flange formed and continuous to the vertical wall provided with the slit is made to face the hood outer panel with a predetermined gap. As a result, when an obstacle such as an animal collides, the vertical wall receives the load at the initial stage of the collision and maintains rigidity, while the flange is not joined in the latter half of the collision and the vertical wall has a slit. Slides backwards and easily collapses to effectively absorb energy. In the invention according to claim 2, the vertical wall, the flat wall, and the connecting flange on the side of the hood inner panel according to claim 1 on which the slit is provided are offset.
Further, in the invention according to claim 3, in the vehicle body hood structure having a plurality of substantially rectangular hollow cross-sections which connect the hood outer panel and the hood inner panel and are continuous in the vehicle width direction,
Providing at least a pair of downward convex ridges in the portion forming the hollow cross section of the hood inner panel, only the flat wall formed at the position sandwiched by the ridges is joined to the outer panel,
Both flanges formed on the outer side of the ridge are made to face the outer panel with a predetermined gap. As a result, the vertical walls of the hood inner panel are increased and the initial rigidity is increased, while the front and rear vertical walls can be easily slid and crushed to absorb energy in the middle and late stages. In the invention described in claim 4, a slit is formed in at least one of the protrusions of the hood inner panel described in claim 3. In the invention according to claim 5, among the flanges of the hood inner panel according to claim 1 or 3, the rear flange has a smaller area or a smaller number than the front flange. In the invention according to claim 6, in the hood inner panel according to claim 1 or 3,
A vertical wall flange or a vertical bead was placed on the slit vertical wall.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. FIG. 1 shows a first embodiment of the present invention. First, the structure will be described. The hood inner 2 joined to the hood outer 1 by the connecting flange 4 has a downward convex cross-sectional shape, and the vertical wall 2R on the vehicle rear side is divided by the slits 5, and the flange 4 on the rear side is divided. Is not joined to the hood outer 1 alternately, but only the front flange 4 is joined to the hood outer 1 to reduce the middle and late load at the time of collision and also maintain the initial load. In the continuous food inner 2, restrain the sideways collapse,
Although it is difficult to reduce the load in the middle and late stages, the hood inner 2 near the striking portion is likely to fall sideways and deform due to the provision of the slit 5. In order to adjust the load in the middle and late stages, it is possible to skip two joints of the rear flange 4 or to skip irregularly one or two joints.

FIG. 2 is an overall view. As in the conventional structure, the joining method is a method of spotting the adhesive 8, and the number of joining points of the rear flange 4 continuous to the rear vertical wall 2R in which the slit 5 is formed. Is decreasing. Further, in order to prevent interference at the time of deformation and to easily control the waveform in an obstacle such as an animal, the vertical wall and the flange 4 are removed where the ridges of the hood inner 2 intersect.

Next, the operation will be described. FIG. 3 is a model in which the hood inner 2 is modeled by a simple link from the crush mode when an obstacle such as an animal collides in the present embodiment and the prior art. The solid line is before impact and the broken line is after impact. A torsion spring is present in each link of such a rectangular link structure, and especially in case 1 where the vertical wall is in the bending mode ((a) in the figure), there is a torsion spring in the intermediate link and the intermediate link. Therefore, it is considered that there are a total of 6 torsion springs. On the other hand, when there is no intermediate link, the torsion springs have only four points when the vehicle falls sideways (see (b) in the figure).
It is considered that there is a torsion spring at a point (see (c) and (d) in the figure).

Before the deformation at the initial stage of the collision, in all cases, four links are formed, and the load value applied in the vertical direction is received by the vertical wall link, so that it does not change so much, and then the buckling mode in which a lateral fall mode or a slip mode occurs In the form, the number of torsion springs is reduced and the load characteristics are also reduced.

In the structure of the present embodiment in which the vertical wall 2R on the rear side of the hood inner 2 is not joined to the hood outer 1, the rear inner wall 2R is deformed while sliding rearward and the torsion springs are as few as three. Energy is gradually absorbed without a large deceleration of the object. Furthermore, the vertical wall of the hood inner 2 having the structure having such a slipping mode is less likely to cause buckling deformation of the V-shape in the front and rear, and does not increase the corners that tend to be crushed. Deform so that 2 is almost flat.

As described above, since the deceleration generated in an obstacle such as an animal can be maintained high in the first half and the rear half speed can be greatly reduced, the hood inner 2 can be made thin. FIG. 4 is a deceleration waveform at this time. The solid line shows the case of the case 4 shown in FIG. 3 of the present embodiment, and the broken line shows the case of the conventional technique shown in the case 1 of FIG. You can see that it is done.

Another embodiment will be described below with reference to the drawings. In describing each embodiment, the same components as those in the first embodiment will be designated by the same reference numerals, and detailed description thereof will be omitted. First, the second embodiment shown in FIGS. 5 and 6 will be described. In the second embodiment, the rear vertical wall 2R having the slits 5 is alternately brought close to the front vertical wall 2F, and a substantially triangular cross section is formed at the close portion to further increase the initial rigidity. . In addition, a portion of the rear vertical wall 2R that is not in close proximity to the front vertical wall 2F is joined to the hood outer 1. Therefore, the torsional rigidity of the hood is maintained as it is. Also in this case, the flange 4 continuous with the rear vertical wall 2R, which is close to the front vertical wall 2F, is not joined to the hood outer 1 and the buckling deformation mode is controlled from the bending buckling mode to the sliding mode. Almost no uncrushed residue occurs. Therefore, energy can be efficiently absorbed without increasing the deceleration in the latter half.

FIG. 7 shows the third embodiment, and when further initial rigidity is required, as shown in the figure, the vertical wall 2R on the rear side is shown.
As a cross section substantially perpendicular to the hood outer 1,
Further increase the support rigidity of R.

FIG. 8 shows Embodiment 4 in which a vertical flange 6 is formed on the vertical wall 2R, and FIG. 9 shows Embodiment 5 in which a bead 7 is formed on the vertical wall 2R. Each of the embodiments is an example in which the rigidity of the vertical wall 2R is increased and the initial rigidity is increased as in the third embodiment shown in FIG. That is, Embodiments 4 and 5 are examples of structures that are not deformed except at the corners. For example, even if the aspect ratio is a >> b, the vertical wall is not easily bent and buckled.

FIG. 10 and FIG. 11 show the sixth embodiment, and are views in the case where the ridges of the hood inner 2 are combined with the hood inner 2 in which the whole is formed in the horizontal direction.

12 and 13 show Embodiment 7, FIG. 14 and FIG.
FIG. 15 is Embodiment 8 and has a structure in which a pair of convex ridges is formed on the hood inner 2 that forms the cross section of the middle section. The convex ridges are formed between the ridges (the central portion of the double-letter shape). To)
The formed flat portion 9 is joined to the hood outer 1,
The front and rear flanges 4 are not joined. In Embodiments 7 and 8, the hood inner 2 has a total of four vertical walls, and the initial rigidity can be further increased.

FIG. 16 shows a ninth embodiment and FIG. 17 shows a tenth embodiment, in which slits 5 are formed in the vertical walls of the seventh and eighth embodiments, respectively.

The embodiment of the present invention has been described in detail above with reference to the drawings. However, the specific configuration is not limited to this embodiment, and design changes and the like without departing from the gist of the present invention. Even if it is included in the present invention.

[0019]

As described above, according to the invention described in claim 1, slits are formed in the vertical walls on the rear side of the front and rear vertical walls of the downwardly convex hood inner joined to the hood outer, Also, because the flange that is continuous with this vertical wall has a structure that is opposed to the hood outer with a certain gap, the vertical rigidity is maintained by the vertical wall during a collision with the vehicle body hood, while the flange is joined in the middle and late stages. Not only the vertical wall slides or falls sideways, but the slit easily crushes the vertical wall to absorb impact energy, and it is possible to reduce the rigidity in the middle and late stages while maintaining the initial rigidity and absorb energy. The effect is obtained. According to the second aspect of the present invention, by offsetting the vertical wall, the initial rigidity can be increased, and there is an effect that a high degree of freedom in design can be obtained. In the invention according to claim 3, since at least a pair of convex stripes are formed on the hood inner forming the hollow cross section, a large number of vertical walls can be formed to increase the initial rigidity, but the coupling with the hood outer is performed by a pair of convex stripes. Since it is a flat wall in the middle of the strip, the vertical wall easily slides or falls sideways in the middle and latter stages of the collision, and it is possible to reduce the rigidity and absorb energy.
According to the invention described in claim 4, in the structure described in claim 3, it is possible to further reduce the rigidity in the middle and later stages, and it is possible to obtain the effect of improving the degree of freedom in design. According to the fifth aspect of the invention, it is possible to obtain the effect that the coupling strength of the flange continuous with the vertical wall on the rear side of the hood inner to the hood outer is reduced, and the rigidity of the vertical wall in the latter half of the collision can be reduced.
In the invention according to claim 6, since the vertical wall flange or the vertical bead is inserted in the vertical wall having the slit, the initial rigidity of this vertical wall can be increased, and the effect of improving the degree of design freedom can be obtained. .

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a bottom view showing the first embodiment.

FIG. 3 is a model diagram of the present invention and prior art when an obstacle such as an animal collides.

FIG. 4 is a deceleration characteristic diagram of the present invention and the prior art when an obstacle such as an animal collides.

FIG. 5 is a perspective view showing a second embodiment.

FIG. 6 is a cross-sectional view showing a second embodiment.

FIG. 7 is a cross-sectional view showing a third embodiment.

FIG. 8 is a perspective view showing a fourth embodiment.

FIG. 9 is a perspective view showing a fifth embodiment.

FIG. 10 is a bottom view showing the sixth embodiment.

FIG. 11 is a sectional view showing a sixth embodiment.

FIG. 12 is a perspective view showing a seventh embodiment.

FIG. 13 is a cross-sectional view showing a seventh embodiment.

FIG. 14 is a perspective view showing an eighth embodiment.

FIG. 15 is a sectional view showing an eighth embodiment.

FIG. 16 is a perspective view showing a ninth embodiment.

FIG. 17 is a perspective view showing a tenth embodiment.

FIG. 18 is a perspective view showing a conventional example.

FIG. 19 is a sectional view showing a conventional example.

FIG. 20 is an explanatory diagram showing an operation of a conventional example.

[Explanation of symbols]

 1 Hood Outer Panel 2 Hood Inner Panel 2R (Rear Side) Vertical Wall 3 Engine 4 Flange 5 Slit 7 Bead 8 Adhesive

Claims (6)

[Claims] 1. A vehicle body hood structure having a plurality of substantially rectangular hollow cross sections that connect a hood outer panel and a hood inner panel and are continuous in a vehicle width direction, wherein the hood inner panel includes front and rear vertical walls and a central flat wall. A flange that is continuous with the upper end of the vertical wall, has a vertical slit formed in at least one of the front and rear vertical walls of the hood inner panel, and is continuous with the slit. And a hood outer panel with a predetermined gap therebetween, the vehicle body hood structure. 2. A vehicle body hood structure, wherein the vertical wall, the flat wall, and the connecting flange of the hood inner panel according to claim 1 on the side where the slits are provided are offset. 3. A vehicle body hood structure having a plurality of substantially rectangular hollow cross sections that connect a hood outer panel and a hood inner panel and are continuous in the vehicle width direction, wherein at least one pair is formed at a portion forming the hollow cross section of the hood inner panel. Provide a convex ridge underneath, and join only the flat wall formed at the position sandwiched by the ridge to the outer panel,
A vehicle body hood structure, characterized in that both flanges formed on the outside of the ridge are opposed to the outer panel with a predetermined gap. 4. A vehicle body hood structure characterized in that a slit is formed in at least one of the ridges of the hood inner panel according to claim 3. 5. The vehicle body hood structure according to claim 1 or claim 3, wherein the rear flange has a smaller area or a smaller number than the front flange. 6. The vehicle body hood structure according to claim 1 or 3, wherein a vertical wall flange or a vertical bead is inserted in a vertical wall having slits.