JP2011020614A - Hood panel for automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hood panel for an automobile having required lightness in weight and basic rigidity, in addition, having excellent pedestrian head protection performance, and surely achieving impact energy absorption, in the hood panel for the automobile formed of fiber reinforced plastic. <P>SOLUTION: The hood panel 1 for the automobile includes: an outer panel 2 formed of fiber reinforced plastic forming an outer surface; and an inner panel 3 formed of fiber reinforced plastic connected to the outer panel 2. The inner panel 3 includes: an inner peripheral portion 6 disposed at the peripheral portion of the outer panel 2; and an inner planar portion 7 integrally formed with the inner peripheral portion 6. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an automotive hood panel made of fiber reinforced plastic (FRP). More specifically, the present invention effectively absorbs impact energy particularly in a collision with a pedestrian while having the required light weight and basic rigidity. The present invention also relates to an automotive hood panel made of fiber reinforced plastic that can protect pedestrians from impacts.

In recent years, instead of metal hood panels, fiber reinforced plastic hood panels whose primary purpose is weight reduction have been actively developed.
This is because the fiber-reinforced plastic is larger than other materials such as metal in terms of specific rigidity and specific strength, so that a lightweight and high rigidity / high strength product can be obtained.
Furthermore, fiber reinforced plastics can be combined with fibers, resins, fiber orientations, and the like according to the required performance, and can be designed with a higher degree of freedom than metal hood panels.

  For this reason, in order to achieve the required rigidity while ensuring the light weight of the entire hood panel, it extends to the outer panel made of fiber reinforced plastic that forms the outer surface over the entire periphery, and the center part. An automobile hood panel (for example, Patent Document 1) in which an inner panel made of fiber reinforced plastic having a frame shape with an opening is joined has been proposed.

  On the other hand, apart from the above-mentioned weight reduction and necessary rigidity, automobiles have recently been required to improve safety in the event of a collision, and in particular, ensure the safety of pedestrians in the event of an accident. It is demanded. When a pedestrian collides with an automobile, the pedestrian receives an impact load on a leg portion, a head, or the like with respect to the bumper or the hood panel of the automobile. In particular, damage to the head increases the risk of pedestrian death or serious injury, so the hood panel, which is likely to collide with the pedestrian's head, has high shock absorption during pedestrian collision. However, it is required to have a structure that suppresses damage to the pedestrian head.

  Regarding the reduction of damage to the pedestrian head, as a standard for evaluating the safety of pedestrian head impact (pedestrian head protection standard), the acceleration that the head receives when it collides with the hood panel and its collision A head injury value (HIC value) calculated from time has been introduced, and it is required to keep this HIC value below a predetermined level.

  In order to satisfy this standard, in conventional metal hood panels such as aluminum and steel, for example, a plurality of substantially frustoconical dimples are formed on the inner panel (for example, Patent Document 2) or parallel to the vehicle longitudinal direction. Many proposals have been made in which an inner panel is provided with a complicated structure, such as those in which multiple convex beads are formed (for example, Patent Document 3).

  With regard to such pedestrian head protection performance, in the case of an automotive hood panel made of fiber reinforced plastic with a frame-shaped inner panel joined to the outer panel described above, the pedestrian's head collides with the inside of the frame shape. In this case, the hood panel may be greatly deformed at the center thereof, and a secondary collision may occur to the engine or the like existing under the hood panel via the deformed hood panel, and there is a risk of causing great damage.

  It is conceivable to apply the technology developed in the metal hood panel as described above to such a problem, but the hood panel for automobiles made of fiber reinforced plastic has greatly different characteristics of the materials used. In addition, since the inner panel layout is different between metal and fiber reinforced plastic, it cannot be applied as it is, and there is no guarantee that the same effect can be obtained.

  Thus, several structures have been proposed for improving the pedestrian head protection performance even in the fiber reinforced plastic hood panel. For example, Patent Document 4 proposes a structure in which a beam-shaped inner panel is provided in an opening of a frame-shaped inner panel. However, in the structure proposed in the above-mentioned Patent Document 4, there is a clear difference in rigidity between the location on the beam-shaped inner panel and the other location (the location having only the outer panel). Not uniform. Therefore, there is a difference in impact absorption performance depending on the location where the pedestrian head collides, and in order to satisfy the HIC value standard, it is necessary to implement a design suitable for each location. Further, the hood panel is configured by joining the entire inner panel including the beam-shaped inner panel to the outer panel, but the outer panel surface design side corresponding to the joint portion between the outer panel and the inner panel is arranged on the outer panel. There is a case where a so-called bonding line appears due to a difference in rigidity between the inner panel and the inner panel. In particular, the hood panel has a beam-shaped inner panel provided near the center of the hood panel, so that the design of the surface is impaired. There is a fear. Furthermore, since the structure of the inner panel itself is complicated by providing the beam-shaped inner panel, problems in molding such as generation of warpage during bonding increase.

  In this way, the conventional fiber reinforced plastic food panel sacrifices simplicity of design, design, moldability, etc. to provide pedestrian head protection performance, Never before.

JP 2002-284038 A JP 2003-191865 A JP 2008-024185 A JP 2008-265696 A

  The present invention solves the above-mentioned problems of the prior art, and has excellent light weight and basic rigidity, and excellent pedestrian head protection, in a fiber reinforced plastic automobile hood panel. An object of the present invention is to provide an automobile hood panel that has performance and can reliably achieve impact energy absorption.

In order to achieve the above object, the automobile hood panel of the present invention has one of the following configurations. That is,
(1) An automotive hood panel comprising a fiber reinforced plastic outer panel forming an outer surface and a fiber reinforced plastic inner panel joined to the outer panel, wherein the inner panel is the outer panel. An automobile hood panel comprising: an inner peripheral edge disposed at a peripheral edge of the inner peripheral part; and an inner planar part integrally formed with the inner peripheral edge.
(2) The automobile hood panel according to (1), wherein the inner planar portion forms a space with the outer panel.
(3) The said inner planar part is the food panel for motor vehicles as described in (1) or (2) which has a surface of the shape which follows the shape of the said outer panel substantially.
(4) The inner peripheral edge is a main rigid member that bears substantially the rigidity required for the hood panel, and at least a part of the structure formed by the inner peripheral edge and the outer panel has a substantially closed cross-sectional structure. The automobile food panel according to any one of (1) to (3).
(5) The inner peripheral edge has a joint with the outer panel along the outer edge of the outer panel, and at least a part of the joint is joined to the outer panel (1) to ( 4) The automobile food panel according to any one of the above.
(6) The food panel for automobiles according to any one of (1) to (5), wherein the outer panel and / or the inner panel has a single plate structure of fiber reinforced plastic.
(7) The automobile food panel according to any one of (1) to (5), wherein the outer panel and / or the inner panel has a sandwich structure in which a core material is interposed between fiber reinforced plastic skin plates.
(8) The automobile food panel according to any one of (1) to (7), wherein at least a part of the reinforcing fibers used in the fiber-reinforced plastic is carbon fiber.
It is.

  According to the present invention, an inner panel made of fiber reinforced plastic can achieve impact energy absorption reliably and has excellent walking performance in a fiber reinforced plastic automobile hood panel while having the required lightness and basic rigidity. It is possible to have human head protection performance.

1 is a schematic plan view of a hood panel according to an embodiment of the fiber reinforced plastic hood panel of the present invention. 1 is an exploded schematic view of a hood panel according to an embodiment of the fiber-reinforced plastic hood panel of the present invention. It is a cross-sectional schematic of A1-A1 arrow in FIG. It is the cross-sectional schematic of A2-A2 arrow in FIG. It is the cross-sectional schematic of B1-B1 arrow in FIG. It is the cross-sectional schematic of B2-B2 arrow in FIG. It is the schematic which shows an example of a deformation | transformation when a pedestrian head collides with the fiber reinforced plastic food panel of this invention. It is the schematic which shows an example of a deformation | transformation when a pedestrian head collides with the fiber reinforced plastic food panel of this invention. It is a schematic plan view showing an example of a conventional fiber reinforced plastic food panel. It is the cross-sectional schematic of C1-C1 arrow in FIG. It is the cross-sectional schematic of C2-C2 arrow in FIG. It is the cross-sectional schematic of D1-D1 arrow in FIG. It is the cross-sectional schematic of D2-D2 arrow in FIG. It is the schematic which shows an example of a deformation | transformation when a pedestrian head collides with the conventional fiber reinforced plastic food panel. It is the schematic which shows an example of a deformation | transformation when a pedestrian head collides with the conventional fiber reinforced plastic food panel.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, exemplary embodiments of the invention will be described with reference to the drawings. Note that the illustrated embodiment is merely an example, and is not limited in the following description.

  FIG. 1 is a plan view of an automobile hood panel according to an embodiment of the present invention as viewed from the engine side, and FIG. 2 is an exploded view of the hood panel shown in FIG. 3 to 6 are cross-sectional views taken along arrows A1-A1, A2-A2, B1-B1, and B2-B2 in FIG. 1, respectively.

  In FIG. 1, 1 is a hood panel, 2 is an outer panel, 3 is an inner panel, and these outer panel 2 and inner panel 3 are made of fiber reinforced plastic.

  Moreover, the outer panel 2 and the inner panel 3 are joined together, and the hood panel 1 is constituted as a whole joined body. The hood panel 1 is mounted in front of the vehicle and covers the engine room and the like.

  The outer panel 2 is a member that forms the outer surface, and constitutes the appearance of the vehicle when attached to the vehicle.

  The inner panel 3 is disposed on the engine room side and functions as a main rigid member that bears the rigidity required for the hood panel 1. Further, the inner panel 3 is provided with a hood lock striker 4 attached to the front of the vehicle body constituting the opening / closing mechanism part for opening and closing the hood panel 1 and hinges 5 attached to both rear ends of the vehicle body as fastening members. The hood panel 1 is attached to the vehicle via these fastening members. In the present embodiment, one hood lock striker 4 and two hinges 5 are shown, but these are not limited. For example, two hood lock strikers 4 are attached to both front ends of the vehicle body. Or you may.

  Further, the inner panel 3 includes an inner peripheral edge portion 6 and an inner planar portion 7 formed integrally and continuously therewith.

  As shown in FIGS. 3 to 6 in the present embodiment, the inner peripheral edge 6 has a hat-shaped cross section and substantially bears the rigidity required for the hood panel 1. Moreover, it has the adhesion part 8 with the outer panel 2 along the outer edge of the outer panel 2, and is substantially closed cross-section structure by joining this adhesion part 8 and the outer panel 2 with an adhesive agent (not shown). Is forming.

  In order to achieve weight reduction while giving the hood panel 1 a desired rigidity, as shown in the present embodiment, the inner peripheral edge portion 6 has a substantially closed cross-sectional structure, and the cross-sectional shape is formed into a hat shape. preferable. In addition, a cross-sectional shape such as a triangle is conceivable. However, in order to give a desired rigidity, the weight is often increased, the molding difficulty level is increased, and the cost is often increased.

  The cross-sectional dimensions such as the height and width of the inner peripheral edge 6 can be appropriately designed so as to ensure the rigidity required for the hood panel 1. On the other hand, when the desired shape cannot be provided, for example, the cross-sectional height of the inner peripheral edge 6 cannot be ensured from the point of clearance with the engine or the like, the adhesive portion 8 on the inner panel 3 is attached to the outer panel 2. In addition to being along the entire periphery of the outer edge, it is also possible to ensure rigidity by forming the adhesive portion 8 at a location inside the hood panel 1 as required. Here, the inside of the hood panel 1 refers to a portion other than the periphery of the outer panel 2. However, in that case, since the bonding line may appear on the surface of the outer panel 2 inside the hood panel 1 and the design may be deteriorated, the thickness and laminated structure of the outer panel 2 and the inner panel 3 around the bonding portion 8 are considered. In order to minimize the difference in rigidity between the outer panel 2 and the inner panel 3 and to minimize the occurrence of bonding lines, and because it is a part of the overall vehicle design and sharpens the design, It is necessary to design with attention to the position of the bonding portion 8 inside the hood panel 1, such as making the bonding line difficult to see by providing the bonding portion 8 along the character line provided by making the outer panel 2 uneven. is there.

  As shown in FIGS. 3 to 6 in the present embodiment, the inner planar portion 7 is integrally formed continuously with the inner peripheral edge portion 6. By forming them integrally, it is possible to connect the front, rear, left, and right of the inner peripheral edge 6 disposed on the periphery of the hood, thereby making it easy to ensure the rigidity required for the hood panel 1.

  A conventional fiber reinforced plastic hood panel is shown in, for example, a schematic plan view (FIG. 9) and a schematic cross sectional view (FIGS. 10 to 13) of a hood panel disclosed in Japanese Patent Application Laid-Open No. 2008-265696 (Patent Document 4). In addition, most of the frame-shaped inner panel 9 and the beam-shaped inner panel 10 having various widths are formed with the adhesive portions 8 at both ends of the hat shape and bonded to the outer panel 2 to form a closed section. is there. In this case, as described above, since the adhesive portion 8 is formed inside the outer panel 2, there is a possibility that a problem occurs in the design.

  In the present embodiment, it adheres only along the outer edge of the outer panel 2, and does not form the bonding portion 8 inside the outer panel 2, so that it becomes a substantially closed cross section, and it is considered that the rigidity is insufficient from the closed cross section. As described above, the shortage can be compensated by forming the inner planar portion 7 continuously and integrally with the inner peripheral edge portion 6. Moreover, when it is further insufficient, it can be dealt with by appropriately adjusting the cross-sectional shape of the inner peripheral edge 6. By doing in this way, high designability is securable in this embodiment.

  Further, the inner planar portion 7 has a space that maintains a predetermined distance between the inner planar portion 7 and a surface that substantially conforms to the shape of the outer panel 2.

  As described above, the conventional fiber reinforced plastic hood panel is, for example, a schematic plan view (FIG. 9) and a schematic cross-sectional view (FIG. 10) of the hood panel disclosed in Japanese Patent Application Laid-Open No. 2008-265696 (Patent Document 4). As shown in FIG. 13, the frame-shaped inner panel 9 has a structure in which a beam-shaped inner panel 10 is provided in the opening. For this reason, there is a difference in rigidity between a place on the beam-shaped inner panel 10 and a place other than that (a place having only the outer panel 2), and there is a problem that the rigidity is not uniform over the entire surface of the hood panel. Therefore, for example, as shown in FIG. 14 and FIG. 15, when the pedestrian head 11 collides with a place on the beam-shaped inner panel 10 and when it collides with that place (a place having only the outer panel 2). Because the deformation of the hood panel is different, there is a difference in impact absorption performance depending on the location of the collision. In order to protect the pedestrian head 11, that is, to satisfy the HIC value standard, it is necessary to implement a design suitable for each hitting point.

  In contrast, the present embodiment is characterized in that the inner planar portion 7 has a space that maintains a predetermined distance from the outer panel 2. In particular, if the inner planar portion 7 has a surface that substantially conforms to the shape of the outer panel 2, the rigidity of the hood panel 1 can be made uniform over the entire hood panel 1. Thereby, as shown in FIG. 7 and FIG. 8, even when the location where the pedestrian head 11 collides is different, the deformation is almost the same, and excellent shock absorbing performance without variation can be ensured.

  Furthermore, the required shock absorbing performance can be further optimized by optimizing the distance from the outer panel 2 and the thickness of the inner planar portion 7 as necessary.

  In addition, since every part has a uniform performance with no variation, it can be designed uniquely over the entire surface of the hood panel 1, so that the design is simple and the design period can be shortened. Can also be achieved.

  On the other hand, if the distance between the outer panel 2 and the inner planar portion 7 becomes too close as a result of the design, the hood panel 1 may be damaged or generate noise due to vibrations during traveling. In order to prevent such damage and vibration, for example, elastic adhesives (such as mastic sealers) and fillers (e.g. urethane foam) that are relatively soft and have little ability to transmit shear deformation, as used in metal food panels. Etc.) is preferably filled between the outer panel 2 and the inner planar portion 7. Inserting an insulator made of foamed resin, glass wool or the like is also a preferable aspect in terms of obtaining damage and vibration preventing effects.

  In the present invention, examples of the joining configuration of the outer panel 2 and the inner panel 3 include rivet joining, rivet joining using an adhesive, and the like in addition to joining with an adhesive. In addition, a structure in which an insert nut is insert-molded into the outer panel 2 or the inner panel 3 and bolted, a structure in which the bolt is bonded to the outer panel 2 or the inner panel 3 and then tightened with a nut, It is good also as a structure which provides the hole for fastening in the inner panel 3, and fastens a bolt and a nut. In any case, the selection can be made in consideration of required rigidity, appearance quality, environmental resistance, and the like. Among them, bonding with an adhesive is preferable, for example, neoprene-phenolic resin, vinyl-phenolic resin, nitrile-epoxy resin, epoxy-phenolic resin, nylon-epoxy resin, modified epoxy resin, polyurethane resin, acrylic resin, silicone resin, polysulfide. Structural adhesives such as resin, elastic epoxy resin, bismaleimide resin, polyimide resin, polybenzimitazole resin, cement-based, low melting glass, alkali metal silicate, phosphate resin, ethylene vinyl acetate resin, ethylene ethyl acrylate resin, or elastic It is more preferable that stress is easily transmitted between the outer panel 2 and the inner panel 3 by bonding with an adhesive called an adhesive.

  In the present invention, each of the outer panel 2 and the inner panel 3 may have a sandwich structure in which a core material is interposed between skin plates made of fiber reinforced plastic, as well as a single plate structure of fiber reinforced plastic. As a core material in the case of adopting a sandwich structure, an elastic body, a foam material, and a honeycomb material can be used, and a foam material is particularly preferable for reducing the weight. As the material of the foam material, for example, a foam material of a polymer material such as polyurethane resin, acrylic resin, polystyrene resin, polyimide resin, vinyl chloride resin, phenol resin, or the like can be used. As the honeycomb material, for example, aluminum alloy, paper, aramid paper or the like can be used, and the honeycomb material is not particularly limited thereto.

  In addition, although the effect of weight reduction can be acquired also in a sandwich structure, when desired rigidity can be ensured by joining the inner panel 3 to a preferable stiffener shape using a single plate structure, the weight is reduced. It is more preferable to use a single plate structure from the point of view of making it.

  In the present invention, the fiber-reinforced plastic refers to a plastic obtained by impregnating a matrix resin into a reinforcing fiber layer and curing it. Examples of the reinforcing fibers constituting the reinforcing fiber layer include reinforcing fibers made of inorganic fibers such as carbon fibers and glass fibers, and organic fibers such as Kevlar fibers, polyethylene fibers, and polyamide fibers. From the viewpoint of easy control of surface rigidity, it is particularly preferable to use carbon fibers as reinforcing fibers. Here, “surface rigidity” refers to rigidity for maintaining an initial predetermined surface shape.

  Examples of matrix resins used for fiber reinforced plastics include thermosetting resins such as epoxy resins, unsaturated polyester resins, vinyl ester resins, phenol resins, and acrylic resins, polycarbonate resins, polyethylene resins, and polypropylene resins. Polyamide resins, polyolefin resins, dicyclopentadiene resins, polyurethane resins, polybutylene terephthalate resins, polyacetal resins, ABS resins, and modified resins obtained by alloying these resins can also be used.

  The automobile food panel of the present invention is manufactured by a fiber reinforced plastic manufacturing method such as a hand lay-up method, an autoclave method, an RTM (Resin Transfer Molding) method, a VaRTM (Vacuum Assisted Resin Transfer Molding) method, an SCRIMP method, or an SPRINT method. It is possible to manufacture. Among these, the injection molding methods such as the RTM method, the VaRTM method, and the SCRIMP method have a short molding cycle and excellent mass productivity as compared with other fiber reinforced plastic manufacturing methods, and a constant preform arrangement. Therefore, it is excellent as a molding method for fiber reinforced plastic automobile parts from the viewpoint of stable quality and high degree of freedom in shape, etc., and the automobile food panel of the present invention can be molded using these molding methods. preferable.

  The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, the present invention can be applied to automobile fender panels, door panels, roof panels, trunk lid panels, etc., but the application range is not limited to these, and vehicles other than automobiles that require collision safety. Application to aircraft and the like is also possible.

DESCRIPTION OF SYMBOLS 1 Hood panel 2 Outer panel 3 Inner panel 4 Hood lock striker 5 Hinge 6 Inner peripheral part 7 Inner surface part 8 Adhesion part 9 Frame shape inner panel 10 Beam shape inner panel 11 Pedestrian head

Claims (8)

  An automotive hood panel comprising an outer panel made of fiber reinforced plastic forming an outer surface and an inner panel made of fiber reinforced plastic joined to the outer panel, wherein the inner panel is a peripheral portion of the outer panel An automobile hood panel comprising: an inner peripheral edge portion disposed on the inner peripheral edge portion; and an inner planar portion integrally formed with the inner peripheral edge portion.   The automobile hood panel according to claim 1, wherein the inner planar portion forms a space with the outer panel.   The automobile hood panel according to claim 1, wherein the inner planar portion has a surface substantially conforming to the shape of the outer panel.   2. The inner peripheral edge is a main rigid member that bears substantially the rigidity required for the hood panel, and at least a part of the structure formed by the inner peripheral edge and the outer panel has a substantially closed cross-sectional structure. The automotive food panel according to any one of to 3. The said inner peripheral part has a junction part with an outer panel along the outer edge of an outer panel, At least one part is joined to the said outer panel among the said junction parts. The food panel for automobiles as described in 1. The automobile hood panel according to any one of claims 1 to 5, wherein the outer panel and / or the inner panel has a single-plate structure of fiber reinforced plastic. The automobile food panel according to any one of claims 1 to 5, wherein the outer panel and / or the inner panel has a sandwich structure in which a core material is interposed between skin plates of fiber reinforced plastic.   The automobile food panel according to any one of claims 1 to 7, wherein at least a part of the reinforcing fibers used in the fiber-reinforced plastic is carbon fiber.

Images