JP2007176328A - Frp structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an FRP structure having such a construction as assuring both a lightweight construction and excellent impact absorbing performance. <P>SOLUTION: The FRP structure composed of an outer 1 to form a face plate and an inner 2 located inside the outer, wherein the inner 2 is formed from a first surface 3 in contact with the reverse surface of the outer, a second surface 4 arranged at a certain distance from the outer, and a third surface 5 tying together the first and second surfaces, and the second surface of the inner has a place where a lattice is formed, while the first surface is formed so that the external edge of the outer is over the whole circumference joined at least partially inside the outer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a structure using a fiber reinforced resin (hereinafter referred to as FRP), and relates to a structure that has necessary rigidity and strength, is lightweight as a structure, and can also have shock absorbing performance.

  In recent years, in addition to rigidity and strength, light weight has been strongly demanded in all structures such as buildings, transportation equipment, and information equipment. In particular, in transportation equipment, a significant reduction in energy consumption is expected due to weight reduction. Therefore, achieving lightweight as well as rigidity and strength is a major technical development issue.

  In the field of transportation equipment, particularly in automobiles, collision safety performance tends to be required as a further requirement, and various research and development have been conducted in order to obtain this performance.

  With regard to collision safety performance, a pedestrian protection function for a collision between a pedestrian and a car has been attracting attention in recent years, as well as the safety performance on the passenger side when a shocking external force is applied. When a car collides with a pedestrian, the pedestrian receives impact loads on the legs and head against the front and hood of the car. It is known that it is essential to reduce damage. Therefore, especially for a hood that easily damages the head, it is required to absorb the shock force as much as possible even in a collision accident and to suppress damage to the head to a minimum.

  Regarding the reduction of the damage to the head, the regulation value is being standardized as the impact mitigation performance of the hood. In particular, the head injury value (HIC) calculated by the acceleration received by the head and its duration is predetermined. It is said that it is necessary to keep it below this level.

  In order to improve the impact mitigation performance of the hood, the hood must be deformed to mitigate the impact in the event of a collision accident. On the other hand, when the hood is deformed to the inside (that is, the engine room side), the internal rigid body It is also necessary to keep the amount of deformation of the hood below a certain level in order to prevent it from abutting against a load or a rigid vehicle body and acting like a stick rod and giving an excessive impact to the head etc. . In other words, from the viewpoint of pedestrian protection, it is necessary to keep the amount of deformation of the hood below a certain level as well as the property that the hood can be deformed in a desirable form and exhibit high impact mitigation performance.

  As a method for achieving these various performances, FRP automobile hoods using carbon fibers have been developed mainly for the purpose of weight reduction in recent years, with the aim of mainly improving the strength and rigidity of necessary parts. Although various types of structures have been proposed (for example, Patent Document 1), no technical disclosure has been made regarding the improvement of impact absorption characteristics such as pedestrian head protection.

  Many other structures have been proposed for improving shock absorption performance such as pedestrian head protection (for example, Patent Document 2), but these proposals have shock absorption characteristics as a main requirement, such as light weight. It is not always enough to consider Thus, there has been no proposal of an FRP structure that achieves both lightness and shock absorption characteristics.

In addition, as a proposal aiming at obtaining shock absorbing characteristics for the purpose of protecting a pedestrian head, a proposal for an automobile hood using a metal material such as aluminum has been made (for example, Patent Document 3). However, in metal hoods, the difference in linear expansion coefficient is a factor, and it is not possible to rely on adhesives for structural joints that transmit outer and inner stresses. Since welding flaws are generated, the joining method is limited, and is generally limited to fixing that joins the inner by bending the outer outer edge portion and filling an elastic adhesive. . In metal automobile hoods, the inner part of the hood other than the outer peripheral part may be fixed with an elastic adhesive, but the rigidity of the adhesive is low, and the role of stress transmission that bears the rigidity of the entire structure is played. It is not a thing that fulfills functions such as flutter prevention and position fixing between the outer and inner. Therefore, the entire structure has a laminated beam structure of outer and inner, and the outer and / or inner or both tend to be relatively thick in order to satisfy the required rigidity and strength in the laminated beam structure. As a result, the weight is increased.
JP 2003-146252 A JP 2005-212255 A JP 2005-75174 A

  Accordingly, an object of the present invention is to provide an FRP structure capable of satisfying lightness and shock absorption characteristics as well as structural requirements such as rigidity and strength required for the structure, and an automobile outer plate and a hood using the FRP structure. It is to provide.

In order to solve the above problems, the FRP structure according to the present invention has the following configuration. That is, (1) It is comprised from the outer which forms a surface board, and the inner located inside an outer, The said inner is arrange | positioned at a fixed distance and the 1st surface which contact | connects the said outer back surface, and outer 2 and a third surface connecting the first surface and the second surface, the second surface of the inner has a portion forming a lattice shape, and the first surface is The FRP structure is characterized in that at least a part of the outer outer edge portion is joined to the outer periphery throughout the outer periphery.

  (2) The FRP structure according to (1), wherein at least half of the area of the first inner surface is bonded to the outer back surface inside the outer surface.

  (3) Said (1)-(2) characterized in that the outer has a sandwich structure composed of a core material and a front and back skin layer composed of a fiber reinforced resin layer arranged so as to sandwich the core material. The FRP structure according to any one of the above.

  (4) The FRP structure according to any one of (1) to (3), wherein a lattice shape formed by the second surface of the inner is a hexagonal honeycomb shape.

  (5) The FRP structure according to any one of (1) to (4), wherein the inner first surface has a circular portion.

  (6) The FRP structure according to (5), wherein the circular shape formed by the first surface of the inner is arranged in a face-centered lattice shape.

  (7) The FRP structure according to any one of (1) to (6), wherein a cross-sectional shape of the inner is an open cross-sectional shape.

  (8) The FRP structure according to (7), wherein the inner cross-sectional shape is a hat-shaped cross section.

  (9) The FRP structure according to any one of (1) to (8), wherein the first surface of the inner has a lightening shaped portion.

  (10) An automobile outer plate using the FRP structure according to any one of (1) to (9).

  (11) An automobile hood, wherein the automobile outer plate according to (10) is applied.

  According to the FRP structure according to the present invention, the inner is properly disposed on the structure, and the outer and the inner are firmly joined. Therefore, in addition to rigidity and strength, the structure is further lightweight. As a result, a good shock absorption characteristic can be obtained by the optimal arrangement of the lattice shape. Moreover, it is possible to adjust these characteristics by changing the joint area of the outer and inner as required.

  The structure of the present structure is also useful when the outer has a sandwich structure, and the high rigidity of the sandwich structure can be further optimized and strengthened for each area by the inner.

  Further, when these lattice shapes are hexagonal honeycomb shapes, optimization of rigidity and strength as a structure is most achieved, and as a result, good weight reduction and impact absorption performance are achieved. Even more preferably, by selecting a joining range and, if necessary, providing a hollowed shape on the inner side, it is possible to achieve further weight reduction and improve impact absorption performance.

  Also, by applying this structure to external sales for automobiles, especially automobile hoods, rigidity, strength and light weight as a product are realized, and depending on the hood area by selecting the joining range and lattice shape such as honeycomb shape, It is possible to optimize the design such as clearance with other parts, necessity, rigidity and strength, and optimization of pedestrian head protection performance.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  1, 2, 3, and 4 show an FRP structure according to an embodiment of the present invention. 1 is an exploded perspective view of an outer 1 that forms a front plate and an inner 2 that is positioned inside the outer 1. FIG. 2 is a perspective view of an FRP structure 6 that joins the outer 1 and the inner 2. FIG. Is a cross-sectional view of the left-right central section 0Y in FIG. 2, and FIG. 4 is a cross-sectional view of the front-rear central section 0X in FIG.

  The outer 1 is a surface member that extends over the entire structure and forms an outer shell, and is formed into a necessary curved surface or flat surface, or a surface shape that combines these depending on the design and application. The inner 2 includes a first surface 3 that contacts the back surface of the outer 1, a second surface 4 that is disposed at a certain distance from the outer 1, and a first surface 3 that connects the first surface 3 and the second surface 4. 3, and a part of the second surface 4 has a lattice shape. The inner 2 has a stiffener structure and shares the overall rigidity of the structure. Also, the inner surface 2 is responsible for local rigidity in the structure surface by optimizing the arrangement of the lattice shape of the second surface 4.

  In this embodiment, the outer 1 and the inner 2 are bonded together by an adhesive, and the outer peripheral portion of the outer side of the outer 1 and the first surface 3 of the inner 2 that is in contact with the outer 1 are all bonded together by the outer peripheral bonding layer 7. Further, at least a part of the back side inside of the outer 1 and the first surface 3 of the inner 2 in contact therewith are joined by the inner joining layer 8, and the outer 1 and the inner 2 constitute a strong closed cross-sectional shape. Thereby, rigidity and intensity | strength are optimized as a structure, As a result, since it becomes the most efficient structure, weight reduction can be obtained.

  The first surface 3 of the outer 1 and the inner 2 is in contact with each other for bonding, but strictly for the purpose of selecting the actual part warpage, assembly accuracy, location and range to be joined, etc. There is no need to match. The gap may be about 0 mm to 5 mm apart, preferably about 0.5 mm to 3 mm. When an adhesive is used, a bonding structure can be formed by filling the area of the back side of the outer 1 and the first surface 3 with an adhesive, and between the outer 1 and the first surface 3. By providing an appropriate gap in between, the outer 1 and the first surface 3 are in contact with each other when the structure is deformed, and damage to the member due to repeated collisions due to vibration or the like, occurrence of a hitting sound, and the like are suppressed. . In order to prevent such a phenomenon of damage and sound, for example, an adhesive or filler that is relatively soft and has a small ability to transmit shear stress, such as those used in metal automobile hoods, is used as the outer 1 and the first. 1 may be used between the surfaces 3, or a similar prevention effect may be provided by inserting an insulator made of foamed resin or the like.

  The bonding configuration of the outer 1 and the inner 2 may include bonding with an adhesive, rivet bonding, rivet bonding using an adhesive, and the like. In addition, an insert nut is insert-molded into the outer 1 or the inner 2 and a bolt The structure to be fastened or the bolt may be bonded to the outer 1 or the inner 2 and fastened with a nut, or a fastening hole may be provided in the outer 1 and the inner 2 for bolt / nut fastening. In any case, the selection can be made in consideration of required rigidity, appearance quality, environmental resistance, and the like. Among them, bonding by an adhesive is preferable, for example, neoprene-phenolic, vinyl-phenolic, nitrile-epoxy, epoxy-phenolic, nylon-epoxy, modified epoxy, polyurethane, acrylic, silicone, polysulfide, elastic epoxy, bismaleimide, polyimide, poly Structure in which stress transmission between outer and inner is made by what is called structural adhesive or elastic adhesive such as benzimitazole, cement, low melting glass, alkali metal silicate, phosphate, ethylene vinyl acetate, ethylene ethyl acrylate, etc. Is more preferable.

  Further, by providing the portion where the second surface 4 forms a lattice shape, the strength and rigidity can be made uniform over the entire structure, and excellent shock absorption characteristics can be obtained. Moreover, it is also possible to optimize the rigidity, shock absorption characteristics, etc. required for the structure by optimizing the size of the lattice shape and the arrangement pitch as necessary. As a lattice shape for obtaining this characteristic, the height of the second surface is preferably 10 mm to 100 mm, and more preferably 25 mm to 60 mm. The width of the second surface is preferably 10 mm to 150 mm, more preferably 25 mm to 100 mm. The pitch of the lattice shape is preferably 30 mm to 500 mm, more preferably 50 mm to 250 mm. As a result, for example, when this structure is applied as an automobile outer plate or an automobile hood, necessary structural characteristics can be achieved with a minimum weight, and an excellent structural component can be obtained. In addition, as described above, the lattice structure is appropriately arranged across the surface of the structure, so that it has excellent shock absorption characteristics. Energy in the case of collision with the hood can be efficiently received in a lattice shape, and good performance can be obtained.

  Regarding the selection of the joining range or place, as shown in the cross-sectional view of the structure in the 0Y direction in FIG. 5, the place where the outer surface of the outer 1 is joined to the first surface 3 of the inner 2 has the necessary rigidity and strength. Considering the weight and shock absorption characteristics, it is possible to select a necessary part instead of joining them all. When not joined at all, the outer and inner have only the function of a mating beam. More preferably, more than half of the area where the first surface 3 of the outer 1 and the inner 2 are in contact is joined. More preferred.

  Regarding the outer, in addition to the single plate structure of FRP, the outer can also be configured in a sandwich structure in which a core material 10 made of, for example, foamed resin is interposed between FRP skin plates 9 as shown in FIG. It is. As a core material in the case of adopting a sandwich structure, an elastic body, a foam material, or a honeycomb material can be used. In order to reduce the weight, it is particularly preferable to use a foam material. As the material of the foam material, for example, a foam material of a polymer material such as polyurethane, acrylic, polystyrene, polyimide, vinyl chloride, phenol, or the like can be used, but is not particularly limited thereto. As the honeycomb material, for example, aluminum alloy, paper, aramid paper or the like can be used, but is not particularly limited thereto. The sandwich structure as shown in FIG. 6 can also achieve the same effect of weight reduction, etc., but the desired rigidity is ensured by joining the inner with the desired stiffener shape using a single plate structure. If possible, it is more preferable to configure a single plate structure.

  In order to give the inner the desired rigidity, strength and lightness, it is preferable that the inner has an open cross section, and more preferably, the cross section has a hat shape as shown in FIG. In addition, closed cross-sectional shapes such as a rectangular shape, trapezoidal shape, and triangle are conceivable, but the weight is often increased and the manufacturing difficulty becomes high due to the hollowing of the structure, which may increase the cost. Many.

  As an open cross-sectional shape, as shown in FIG. 7, in addition to the above-described hat shape (a), I-shape (b), C-shape (c), L-shape (d), hat wall perforated shape (e), hat separation There are shapes (f) and the like. Considering the cross-sectional rigidity, adhesion area, moldability, etc., a hat-shaped cross-section is more preferable because the balance between rigidity and weight is good. However, for example, when this FRP structure is applied to an automobile outer plate, if there is a problem of clearance with other parts, and there is sufficient rigidity and strength required, a shape other than a hat-shaped cross section is adopted, You may comprise so that other performance requirements may be satisfy | filled.

  Further, in order to further reduce the weight of the inner 2, it is possible to provide a lightening portion 101. As shown in FIG. 8, in particular, when a thinned portion 101 is provided in the inner 2 of the structure as an automobile hood, a thinned portion having a diameter of about φ5 mm to 150 mm, preferably about φ50 mm to 120 mm is used. The necessary local rigidity can be maintained together with good lightness.

  Examples of the reinforcing fibers according to the present invention include inorganic fibers such as carbon fibers and glass fibers, and reinforcing fibers made of organic fibers such as Kevlar fibers, polyethylene fibers, polyamide fibers, and PBO fibers. Carbon fiber is particularly preferable from the viewpoint of rigidity and strength per weight. Examples of the FRP matrix resin include mature curable resins such as epoxy resins, unsaturated polyester resins, vinyl ester resins, and phenol resins. Furthermore, polyamide resins, polyolefin resins, dicyclopentadiene resins, polyurethane resins, etc. A mature plastic resin can also be used. The FRP composed of these reinforcing fibers and matrix resin can be formed as a single layer, but in order to develop desirable characteristics (especially desirable bending rigidity and torsional rigidity in a specific direction) It is preferable to do. Further, the mechanical properties of FRP can be appropriately set depending on the selection and combination of the reinforcing fibers and matrix resin as described above, the orientation and volume content of the reinforcing fibers, the laminated configuration, and the like.

  FIG. 9 shows an FRP structure according to another embodiment of the present invention. Similarly, an FRP structure is configured by the outer 11 and the inner 12, and the inner 12 includes a first surface 13 that contacts the back surface of the outer 11, and a second surface 14 that is disposed at a certain distance from the outer 1. The first surface 13 and the second surface 14 are constituted by a third surface 15, and a part of the second surface 14 has a lattice shape. In the present embodiment, the lattice shape of the inner second surface 14 is arranged in a hexagonal honeycomb shape. By adopting a hexagonal honeycomb shape, higher rigidity can be obtained with less material, and more uniform rigidity and strength can be obtained in the plane direction, even in a lattice shape. In addition, more preferable shock absorption characteristics can be obtained. Therefore, the whole structure can be obtained with less rigidity and strength, and more preferable shock absorption characteristics can be obtained. Therefore, for example, when this is applied to an automobile outer plate member or an automobile hood, it can be made lighter in a state satisfying the rigidity and strength required as parts, particularly a pedestrian head. When it is necessary to absorb collision energy such as protection, performance can be efficiently exhibited by the honeycomb shape.

  FIG. 10 shows an FRP structure according to still another embodiment of the present invention. Similarly, an FRP structure is configured by the outer 31 and the inner 32, and the inner 32 includes a first surface 33 that contacts the back surface of the outer 31, and a second surface 34 that is disposed at a certain distance from the outer 31. The first surface 33 and the second surface 34 are composed of a third surface 35, and a part of the second surface 34 has a lattice shape. In the present embodiment, the first surface 33 of the inner 32 has a circular shape. In such a case, particularly for the protection of a pedestrian head required for an automobile hood, the inner of the position where the head contacts is circular, which is preferable because the impact is reduced. These circular shapes may be arranged in a lattice shape, but more desirably, when arranged in a face-centered lattice shape, as shown in FIG. 10, dense and uniform lattice distribution, or inner rigidity distribution is achieved. In addition to rigidity and strength, impact absorption characteristics are further improved, which is more preferable.

It is a disassembled perspective view of the FRP structure which concerns on one embodiment of this invention. It is a perspective view of the FRP structure concerning one embodiment of the present invention. It is 0X sectional drawing of the FRP structure of FIG. It is 0Y sectional drawing of the FRP structure of FIG. It is a schematic diagram of the junction part or range concerning this invention. It is a schematic diagram in case the outer concerning this invention is a sandwich structure. It is an exemplary schematic diagram of the inner stiffener shape according to the present invention. It is a schematic diagram of the lightening shape concerning this invention. It is a disassembled perspective view of the FRP structure which concerns on another embodiment of this invention. It is a disassembled perspective view of the FRP structure which concerns on another embodiment of this invention.

Explanation of symbols

1, 11, 31 Outer 2, 12, 32 Inner 3, 13, 33 First surface 4, 14, 34, which is in contact with the inner outer back surface 5, 5, 15 installed at a certain distance from the inner outer 35 3rd surface 6 which connects the 1st surface and the 2nd surface, FRP structure 7, outer periphery joining layer 8, internal joining layer 9, FRP skin board 10, core material 101, a hollow part

Claims (11)

The outer surface is formed of an outer layer and an inner layer located on the inner side of the outer layer. The first surface is in contact with the outer back surface, and the second surface is disposed at a certain distance from the outer surface. , The third surface connecting the first surface and the second surface, the second surface of the inner has a portion forming a lattice shape, the outer surface of the outer surface of the first surface is An FRP structure characterized in that at least a part is joined inside the outer part over the entire circumference. 2. The FRP structure according to claim 1, wherein more than half of the area of the first surface of the inner is bonded to the outer back surface inside the outer. The FRP according to any one of claims 1 to 2, wherein the outer has a sandwich structure composed of a core material and front and back skin layers composed of a fiber reinforced resin layer arranged so as to sandwich the core material. Structure. The FRP structure according to any one of claims 1 to 3, wherein a lattice shape formed by the second inner surface is a hexagonal honeycomb shape. The FRP structure according to claim 1, wherein the inner first surface has a circular portion. 6. The FRP structure according to claim 5, wherein the circular shape formed by the first inner surface is arranged in a face-centered lattice pattern. The FRP structure according to claim 1, wherein the inner cross-sectional shape is an open cross-sectional shape. The FRP structure according to claim 7, wherein the inner cross-sectional shape is a hat-shaped cross section. The FRP structure according to any one of claims 1 to 8, wherein the first surface of the inner has a lightening-shaped portion. An automobile outer plate using the FRP structure according to any one of claims 1 to 9. An automobile hood, wherein the automobile outer plate according to claim 10 is applied.

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