JP4802617B2 - Automotive bonnet - Google Patents

Description

  The present invention relates to an automobile bonnet made of FRP (fiber reinforced plastic), and more particularly to an automobile bonnet that can absorb impact load more gently and more effectively.

  In recent years, automobiles have been required to improve safety in the event of a collision, and in particular, to improve pedestrian protection performance in the event of an accident, as well as safety on the occupant side when shocking external forces are applied. It is requested. When an automobile collides with a pedestrian, the pedestrian receives impact loads on the legs and head against the front and bonnet of the automobile. It is said that reducing the damage is essential. Therefore, especially for a bonnet that easily damages the head, it is required to absorb the impact force as much as possible even in the event of a collision and to keep the damage to the head small.

  Regarding the reduction of the damage to the head, the regulation value is being standardized as the impact mitigation performance of the bonnet. In particular, the head injury value (HIC) calculated by the acceleration received by the head and its duration is predetermined. It is desirable to keep it below this level. In addition to such impact mitigation performance, when the bonnet is deformed to the inner side (that is, the engine room side) at the time of a collision accident etc., it comes into contact with the internal rigid body mounted object or the rigid body, etc. In order to prevent an excessive impact on the head or the like, it is desired to suppress the deformation amount of the bonnet to a certain level or less, although it varies depending on the vehicle type. In other words, from the viewpoint of pedestrian protection, while the bonnet is required to have a characteristic that can be deformed in a desirable form and exhibit high impact mitigation performance, it is desirable to have rigidity that can suppress the deformation of the bonnet to a certain level or less. It is.

  By the way, in recent years, FRP-made automobile bonnets are being developed for the first purpose of weight reduction, and various structures have been proposed mainly for the purpose of improving the strength and rigidity of necessary parts ( For example, Patent Document 1), as an FRP automobile bonnet, there are few proposals for an appropriate structure from the viewpoint of satisfying the required performance in the event of a collision accident as described above.

  Conventionally, various FRP bonnets including an FRP outer that forms the front side and an FRP inner joined to the back side of the outer side have been proposed. For example, FIG. The same layout as the inner 102 of the metal bonnet 103 having the metal outer 101 and the metal inner 102 as shown in FIG. 6 or along the outer edge of the FRP outer 111 as shown in FIG. An FRP bonnet 113 having a frame-shaped FRP inner 112 extending over the entire circumference of the outer 111 is formed.

However, when the FRP inner 112 having such a frame shape is joined to the outer 111, the overall rigidity of the FRP bonnet 113 is kept high and the amount of deformation is suppressed, but the desired impact mitigation performance as described above is achieved. It becomes difficult to demonstrate. In particular, at the time of a collision accident or the like, as shown in FIG. 7, the impact load F due to the pedestrian's head or the like is often applied to the hood of the automobile 121 obliquely from the front. If 112 is provided, the rigidity of the bonnet 113 as a whole becomes high, and the impact load F can be received softly only in a relatively narrow region of the center portion of the outer 111. As a result, the absorption performance of the impact load F is obtained. May become insufficient. That is, in FIG. 8, the shock load absorption performance on the FRP bonnet 113 is represented by a substantially circular relatively narrow region 114 in the central portion of the outer 111 so that the amount of deformation when the shock load is received is indicated by contour lines. However, the impact load F may not be absorbed well. If the area of the impact load absorbing region is further expanded or the region can be expanded in a more appropriate direction, better and more desirable impact load absorbing performance can be obtained.
JP 2003-146252 A

  Therefore, the object of the present invention is to pay attention to the problems in the conventional FRP bonnet as described above, and in particular, while ensuring the necessary basic rigidity required for the bonnet, in particular, the impact load is softer and softer more effectively. The object is to provide an FRP automobile bonnet that can be absorbed.

In order to solve the above-described problems, an automobile bonnet according to the present invention is an automobile bonnet having an FRP outer and an FRP inner bonded to the back side thereof. only the side edge, extends continuously these portions substantially have a high rigidity portion formed by the inner and the high rigidity portion, locally at the location in the both side edge portions It consists of what is characterized by being divided into . In other words, this high-rigidity portion is arranged only on the front edge and both side edges of the FRP bonnet, not on the rear side, and first, the reinforcement basically different from the structure shown in FIG. It becomes a structure.

The high-rigidity portion has an FRP bonnet substantially as a single plate configuration (including both an FRP single plate configuration and a sandwich configuration of a core material and an FRP skin plate), and only the specific portion of the FRP bonnet is high. Although it is possible to have a rigid structure, the automobile bonnet according to the present invention is an automobile bonnet having an FRP outer and an FRP inner bonded to the back side thereof. Thus, the inner forms the high-rigidity portion .

Further, in the automobile bonnet according to the present invention, the high-rigidity portions provided on both side edges only need to extend substantially continuously along the both side edges, and are locally interrupted. Ri also der be configured to have, in the present invention, the high rigidity portion formed by the inner, are configured to be locally divided positions in the both side edges. Then, the high-rigidity portion of the high-rigidity portion is positioned at the positions in the side edge portions corresponding to the virtual bonnet crossing line that assumes the so-called く -shaped deformation of the bonnet. However, it is preferable that the low-rigidity portion having a low rigidity is disposed. However, such a low-rigidity portion is formed by a portion where the high-rigidity portion is locally divided at positions in both side edges. Can be configured. In general, from the viewpoint of protecting both pedestrians and occupants, it is desirable that such a configuration bend the bonnet into a "<" shape when the bonnet is deformed in a collision accident or the like. This is a configuration that takes this point into consideration.

  In the automobile bonnet according to the present invention, the high-rigidity portion extending from both side edge portions of the bonnet may extend over a portion including a hinge mounting portion that is an engaging portion to the vehicle body side of the bonnet. preferable. Moreover, it can also be set as the structure where the striker is mounted | worn with the said highly rigid part extended the front edge part of a bonnet.

  In such an automobile bonnet according to the present invention, the disadvantages of the FRP bonnet in which the FRP inner having the frame shape as shown in FIG. 6 is arranged, that is, (1) the portion having the inner is rigid. High, HIC increases when the head collides (the damage to the head is large). (2) In areas where there is no inner, the outer is supported by the outer circumference, and even if the head collides, the deformation is sufficient. (3) Although a slight improvement can be obtained if the inner is made smaller, the bending rigidity and torsional rigidity of the bonnet as a whole are lowered, and the necessary rigidity can be secured. (4) If the inner is omitted, all of the drawbacks such as insufficient bending rigidity and torsional rigidity of the entire bonnet can be effectively eliminated.

That is, in the vehicle bonnet according to the present invention, the high rigidity portion ( that is, the high rigidity portion by the inner) is disposed only on the front edge and both side edges of the bonnet, and is not disposed on the rear side. As shown in FIG. 7, when an impact load is applied obliquely from the front, the bonnet has a structure that can be largely deformed toward the rear side where the high-rigidity portion is not disposed. The deformation region due to impact loads such as collisions will be widely distributed in the rear, and the impact loads will be received more gently and softly, and will be absorbed more effectively. Since this rear portion has a relatively space between the bonnet and the vehicle body side, the structure according to the present invention can be said to be an extremely efficient structure.

And by providing a highly rigid part only in the front edge part and both side edge part of a bonnet, the required basic rigidity requested | required of a bonnet is ensured efficiently. That is, by arranging the high-rigidity part on the front edge, especially over the entire width of the front edge, the bending rigidity of the bonnet is maintained sufficiently high, and the high-rigidity part is included on both side edges, especially including hinge attachment parts. By arranging it over the entire length, the torsional rigidity of the bonnet is maintained sufficiently high. Furthermore, as described above, since the high-rigidity portion is locally divided at the positions in the side edges, the bonnet is bent into a “<” shape when the bonnet is deformed in a collision accident or the like. Desirable variations are also possible.

As described above, according to the bonnet for an automobile according to the present invention, the deformation region for absorbing the impact load in the FRP bonnet can be appropriately expanded to the bonnet rear side, and a desirable deformation mode when the bonnet is deformed is also possible. However, it is possible to give superior shock absorbing performance that is more gentle and soft. Therefore, it is possible to greatly improve the pedestrian head protection function while maintaining basic rigidity such as bending and torsional rigidity required for the bonnet.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an automobile bonnet according to one embodiment relating to the basic form of the present invention, and shows a view of the entire bonnet from the back side. In FIG. 1, reference numeral 1 denotes an entire hood for an automobile. In the illustrated example , the bonnet 1 is joined to an outer 2 made of FRP located on the front surface side of the automobile and the back surface side thereof. It consists of an inner 3 made of FRP that forms a rigid part. The outer 2 made of FRP extends over the entire surface of the bonnet in the surface direction, and is formed into a necessary curved surface shape according to the vehicle type. The outer 2 may be configured as a single plate structure of FRP, or may be configured as a sandwich structure in which a core material (for example, a core material made of foam) is interposed between FRP skin plates. The FRP inner 3 can also be configured in a sandwich structure, but it is easily desired by joining to the outer 2 as a stiffener shape (for example, a stiffener shape having a hat-shaped cross-sectional shape) with a single plate structure. Therefore, it is preferable to configure a single plate structure.

In the illustrated example , the inner 3 extends over the entire width of the front edge A of the outer 2 of the bonnet 1 and the entire length of both side edges B so as to extend completely continuously. Therefore, the inner part 3 as a highly rigid part is not arranged in the rear part of the outer 2 of the bonnet 1. A hinge attachment portion 4 that is an engagement portion of the bonnet 1 to the vehicle body side is provided at a rear portion of the inner 3 as a highly rigid portion extending from both side edge portions B. A striker 5 is provided at the center of the inner 3 as a high-rigidity portion extending from the front edge A.

  The FRP in the hood for automobiles according to the present invention refers to a resin reinforced with reinforcing fibers. Examples of the reinforcing fibers include inorganic fibers such as carbon fibers and glass fibers, Kevlar fibers, polyethylene fibers, and polyamide fibers. Reinforcing fibers made of organic fibers such as Carbon fiber is particularly preferable from the viewpoint of the ease of controlling the rigidity of the bonnet as described above. Examples of the FRP matrix resin include thermosetting resins such as epoxy resins, unsaturated polyester resins, vinyl ester resins, and phenol resins, and polyamide resins, polyolefin resins, dicyclopentadiene resins, polyurethane resins, and the like. These thermoplastic resins can also be used. In addition, as the core material in the case of adopting the sandwich structure, an elastic body, a foam material, and a honeycomb material can be used, and a foam material is particularly preferable for weight reduction. The material of the foam material is not particularly limited, and for example, a foam material of a polymer material such as polyurethane, acrylic, polystyrene, polyimide, vinyl chloride, or phenol can be used. The honeycomb material is not particularly limited, and for example, aluminum alloy, paper, aramid paper or the like can be used.

  In the FRP automobile bonnet 1 configured as described above, only the front edge portion and both side edge portions of the bonnet are reinforced with the inner 3 as the high rigidity portion, and the inner 3 is not disposed on the rear side of the bonnet. Therefore, for example, in FIG. 2 corresponding to FIG. 8 described above, the impact load absorption performance on the FRP bonnet 1 is shown, and the amount of deformation when the impact load is received is shown by contour lines. The area 10 is greatly enlarged toward the rear side of the bonnet 1, whereby the impact load applied obliquely from the front as shown in FIG. 7 is gently and softly absorbed, and a pedestrian at the time of a collision or the like. Head protection is performed more appropriately.

  On the other hand, the bending rigidity required for the bonnet is ensured by the inner 3 as the high-rigidity portion arranged at the front edge A of the bonnet, and the screw necessary for the bonnet is ensured by the inner 3 as the high-rigidity portion arranged at both side edges B. Torsional rigidity is ensured.

FIG. 3 shows an automobile bonnet according to another embodiment, and shows a view of the entire hood from the back side. In the vehicle bonnet 11 according to the present embodiment, compared with the embodiment shown in FIG. 1, the middle-fold deformation mode, which is a desirable deformation mode of the outer 12 at the time of a frontal collision or the like, the so-called “ku” -shaped bending deformation is considered. The FRP inner 13 as the high-rigidity part is more rigid than the high-rigidity part at a position in the side edge B corresponding to the virtual bonnet crossing line 14 assuming a “く” -shaped deformation of the bonnet. The low-rigidity portion 15 having a low height is arranged. The low rigidity portion 15 may be formed by weakening the rigidity of the inner 13 at this portion, or may be formed by a structure in which the inner 13 is not locally arranged at this portion.

  In such a configuration, the portion along the virtual bonnet crossing line 14 where the low-rigidity portion 15 is disposed becomes a low-rigidity portion extending in the width direction of the vehicle body as viewed from the entire bonnet, and the outer 12 It becomes the starting point of the "K" character bending deformation. By intentionally changing the deformed shape to a “<” shape, both the pedestrian and the occupant can be more appropriately protected.

Further, as described above, in the above-described embodiment, the low-rigidity portion 15 can be formed by a structure in which the high-rigidity portion is not locally arranged, particularly by a structure in which the inner 13 is not locally arranged. For example, as shown the automobile hood according to an embodiment of the present invention in FIG. 4, the high rigidity portion may be a structure that is locally divided positions in the both side edges. In the automobile bonnet 21 shown in FIG. 4, an FRP inner 23 is bonded to the back side of the FRP outer 22 as a high-rigidity portion, and the high-rigidity portion formed by the inner 23 is in the middle of both side edges. Is locally divided in the longitudinal direction of the vehicle body. The dividing portion 24 preferably includes both side edge positions corresponding to the virtual bonnet crossing line as shown in FIG.

  In such a structure, the arrangement part of the inner 23 can be suppressed to a necessary minimum, and the entire configuration can be efficiently simplified. In addition, when an impact load is applied obliquely from the front as shown in FIG. 7, not only the distribution of the bonnet deformation can be expanded to the rear side, but can be appropriately expanded in both directions, so that, for example, at the time of a collision Thus, pedestrian head protection is more appropriately performed.

It is a reverse view of the bonnet for motor vehicles based on one embodiment regarding the basic form of this invention. FIG. 2 is a contour map of a deformation amount showing a state of impact absorption when an impact load is applied to the bonnet of FIG. 1. It is a reverse view of the bonnet for motor vehicles concerning another embodiment. It is a reverse view of the bonnet for motor vehicles based on one embodiment of this invention. It is a reverse view of the conventional metal bonnet. It is a reverse view of the conventional FRP bonnet. It is explanatory drawing which showed an example of a mode that an impact load is added to a bonnet. FIG. 7 is a contour map of a deformation amount showing a state of shock absorption when an impact load is applied to the FRP bonnet of FIG. 6.

Explanation of symbols

1, 11, 21 Automotive bonnet 2, 12, 22 FRP outer 3, 13, 23 FRP inner 4 forming high rigidity part 4 Hinge mounting part 5 Striker 10 Impact load absorption area 14 Virtual bonnet crossing line 15 Low Rigid part 24 Split part A Front edge B Both side edges

Claims (4)

An automotive bonnet having an FRP outer and an FRP inner bonded to the back side thereof , and these portions extend substantially continuously only on the front edge and both side edges. , have a high rigidity portion formed by said inner and automobile bonnet which the high rigidity portion, characterized in that it is locally split position in the two side edges. 2. The automobile bonnet according to claim 1 , wherein the high-rigidity portion extending from both side edge portions of the bonnet extends over a portion including a hinge attachment portion that is an engagement portion of the bonnet to the vehicle body side. The automobile bonnet according to claim 1 or 2 , wherein a striker is attached to the high-rigidity portion extending from a front edge of the bonnet. The FRP is made of carbon fiber reinforced plastics, automotive hood according to any one of claims 1-3.

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