JP2009166408A - Structural member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structural member having a FRP-made reinforcing member, and reduced in cost, by preventing the strength reduction of an adhesive member, narrowing the strength variance of the FRP-made reinforcing member, and also reducing working man-hours. <P>SOLUTION: The structural member is characterized in that a reinforcing fiber-containing fiber-reinforced resin-made reinforcing member is fitted to a main structural material. The reinforcing member has a convex main reinforcing part and an adhesive part at the least and a raised adhesive surface-modified part is formed as a portion of the adhesive part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a structural member composed of a reinforcing member and a main structural material, and more particularly to the shape of an adhesive surface with a main structural material in a FRP (fiber reinforced resin) reinforcing member.

  In recent years, structural members made of CFRP (carbon fiber reinforced resin) have been developed for the purpose of reducing the weight of structural bodies such as automobiles and railways, particularly in terms of improving strength and rigidity. In order to make these members lightweight, high-rigidity, and high-strength structures, for example, as shown in Patent Document 1, reinforcing members such as ribs and stiffeners are appropriately attached to the main structural material, so that a hollow structure, a multilayer structure, or a sandwich structure is used. Used in form.

  In the metal member, as shown in Patent Document 2, rivet joining or welding is often used for ease of processing. However, unlike metal, FRP cannot be welded due to the characteristics of the material. In addition, when rivet bonding is applied to the FRP, there is a problem that the strength of the member is reduced starting from the tearing of the fiber layer that occurs during drilling. Therefore, as a method of joining the FRP reinforcing members, a method of bonding both members using an adhesive is the mainstream.

  In the bonding method using the adhesive, the adhesive strength and the fracture position are likely to vary due to uneven thickness of the adhesive or protrusion, unevenness of the adhesive surface, solvent adhesion, and the like.

  Therefore, in the joining method using an adhesive, in order to control the failure mode of the member, as shown in FIG. 8, it has been generally performed to provide a cutout portion in the reinforcing member. In other words, the strength at the notch was set to be relatively lower than the strength of the surrounding adhesive part, and it was designed to break at the notch.

However, in order to provide a notch in the FRP reinforcing member, it is necessary to process the base material before molding, or to perform notch processing on the molded product after molding, and extra man-hours for providing the notch are generated. Further, when the notch is provided, the fiber is divided at the notch, so that the strength of the member at the notch is not uniform unlike the metal. Further, since the reinforcing member has a structure in which stress concentrates in the notch and breaks from the notch, there is a problem that the strength variation as the reinforcing member increases.
JP 2003-291219 A JP-A-5-4579

  In view of the above circumstances, the present invention provides a structural member capable of controlling a fracture mode by reducing variation in strength caused by fracture at a notch in a structural member having an FRP reinforcing member. It is in.

  In order to solve the above problems, according to the present invention, a reinforcing member made of a fiber reinforced resin containing reinforcing fibers is a structural member attached to a main structural material, and the reinforcing member is a convex main reinforcing portion. A structural member is provided that includes at least an adhesive portion, and a convex bonded surface processed portion is formed on a part of the adhesive portion.

  Moreover, according to the preferable form of this invention, the longest distance D from the top part of the said adhesion surface process part to the main structure material is 30-80 with respect to the longest distance H from the top part of the said main reinforcement part to the main structure material. %, The structural member is provided.

  Moreover, according to the preferable form of this invention, the maximum width L between the both ends of the convex processus | protrusion formed as the said adhesion surface process part is with respect to the longest distance D from the top part of the said main reinforcement part to the main structure material. A structural member is provided that is in the range of 80-150%.

  Moreover, according to the preferable form of this invention, the longest distance D from the top part of the said main reinforcement part to a main structure material is 5 mm or more, The structural member characterized by the above-mentioned is provided.

  Moreover, according to the preferable form of this invention, the said structural member consists of fiber reinforced resin, The structural member characterized by the above-mentioned is provided.

  According to a preferred embodiment of the present invention, there is provided a structural member characterized in that at least one carbon fiber reinforced resin cloth material is included in the reinforcing member.

  Moreover, according to the preferable form of this invention, the said structural member is a structural member for motor vehicles, The structural member characterized by the above-mentioned is provided.

  Further, according to a preferred embodiment of the present invention, there is provided a structural member characterized in that a use application of the automotive structural member is any one of an automotive hood, a floor panel, a trunk lid, a roof, and a door panel. .

  Moreover, according to the preferable form of this invention, the said structural member is a member for rail vehicles or a member for ship structures, The structural member characterized by the above-mentioned is provided.

  The terms are defined below.

  In the present invention, the “main structural material” refers to a base material in the entire structure in which a reinforcing material is joined by an adhesive. The bonding surface shape of the main structural material does not need to be a flat surface, and a curved surface may be formed or a minute hole or a through hole may be formed on the surface.

  In the present invention, the “reinforcing member” refers to various members that are joined to the main structural material by an adhesive. Often used for the purpose of improving the rigidity and strength of the main structural material, the size is not limited, and a plurality of reinforcing members may be joined to one main structural material. From the viewpoint of weight reduction, it is often a monocoque structure that is hollow when joined to the main structural material.

  In the present invention, the “bonding portion” refers to a region where both are bonded via an adhesive when the reinforcing member is bonded to the main structural material. Even if an adhesive is applied to a part or the entire surface of any member, they are not joined unless both members are in contact, and such a region is not an adhesive portion.

  The adhesive part is often rectangular as shown in FIG. 2, but depending on the shape of the reinforcing member, the maximum width is referred to as the adhesive part width and the maximum length is referred to as the adhesive part length.

  In the present invention, the “bonded surface processed portion” refers to a portion where a part of the bonded portion is formed into a convex shape so as to maintain a distance from the main structural material and not to be bonded to the main structural material. The bonding surface processed portion is provided by forming a convex shape without providing a notch in a portion where a conventional notch portion is provided.

  Here, the “adhesive surface processed part height D” refers to a length corresponding to the longest distance from the top of the part formed into a convex shape to the main structural member.

  Here, the “adhesive surface processed part length L” refers to a length corresponding to the maximum width between both ends of the convex protrusion formed as the convex adhesive surface processed part. The cross section having the bonded surface processed portion has lower strength than the cross section including the bonded portion, and breaks from this position.

  In the present invention, the “main reinforcing portion” is a portion for improving the rigidity and strength, which are the main purposes of the reinforcing member, and indicates a portion obtained by removing the bonding portion and the bonding surface processed portion from the reinforcing member.

  Here, the “main reinforcing portion height H” refers to a length corresponding to the longest distance from the top of the convex main reinforcing portion to the main structural member.

  In the present invention, the “adhesive” is a substance composed of a material different from the main structural material that forms the joint together. Unlike rivet bonding or welded bonding, A material that adheres along the surface of the main structural material as an amorphous object with a Young's modulus lower than that of the main structural material, and then bonds the main structural material and the reinforcing member by curing by heating or drying. Say. Typically, it is a liquid or gel-like object before curing. From the viewpoint of improving the bonding strength, the adhesive may be pretreated on the main structural material or may be composed of a plurality of components. Moreover, not only liquid but solid and powder may be sufficient. Further, the adhesive may be applied to the reinforcing member instead of the main structural material, or may be applied to both.

  In the present invention, “FRP” refers to a resin reinforced with reinforcing fibers, and examples of reinforcing fibers include carbon fibers, inorganic fibers such as glass fibers, Kevlar fibers, polyethylene fibers, polyamide fibers, and boron. It is also possible to use reinforcing fibers made of organic fibers such as fibers and polyparaphenylene benzobisoxazole (PBO) fibers. Carbon fiber is particularly preferable from the viewpoint of easy control of rigidity and strength of the structural member. Examples of the matrix resin of FRP include thermosetting resins such as epoxy resins, unsaturated polyester resins, vinyl ester resins, phenol resins, dicyclopentadiene resins, polyurethane resins, and further, polyamide resins, polyolefin resins, Thermoplastic resins such as polypropylene resin can also be used.

  In the present invention, the “core material” is a general term for materials inserted particularly between surface layer materials in order to obtain a light weight as a structure and a cross-sectional shape, and an elastic body, a foam material, and a honeycomb material are mainly used. Is done. 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.

  As described above, according to the FRP structural member of the present invention, it is possible to reduce the variation in strength caused by the fracture at the notch and to control the fracture mode of the member.

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

  FIG. 1 shows a state in which the reinforcing member 1 in one embodiment of the present invention is attached to the main structural member 2.

  The reinforcing member 1 is a convex structure having a main reinforcing portion 14 that is a convex bulge in the center and adhesive surfaces to the main structural member 2 on both sides thereof. Also, the adhesive surface has two adhesive surface processed portions 11 processed into a convex shape near the center of the adhesive surfaces on both sides, and a total of four locations on both sides are actually bonded to the main structural material. The bonding portion 12 becomes. The processing of the bonding surface processed portion 11 may be performed simultaneously with the convex shape processing of the main reinforcing portion 14, and as in the case where the notch portion 13 is provided, it is processed into a base material before molding, or is formed into a molded product after molding. There is no need for notching, and man-hours can be reduced.

  FIG. 2 shows a joining member 99 in which the reinforcing member 1 shown in FIG. 1 is bonded onto the main structural member 2.

  The bonding portion 12 of the reinforcing member 1 is bonded to the main structural member 2 with the adhesive 4 by the adhesive 4. Here, since the bonding surface processed portion 11 of the reinforcing member 1 has a convex shape in the same direction as the bulge of the main reinforcing portion 14 with respect to the surface of the bonding portion 12, it does not contact the main structural member 2 and is bonded. Does not form a surface. By giving such a shape, the rigidity of the reinforcing member 1 in the vicinity of the bonding surface processed portion 11 can be reduced as compared with other portions bonded to the main structural member 2, and the bonding member 99 is bonded to the bonding surface. The processing part 11 is used as a starting point for destruction.

  In general, the adhesive 4 is applied only to the part to be bonded. However, according to the present invention, the bonding surface processed portion 11 that is not desired to be bonded has a sufficient distance from the main structural material 2. Even if the adhesive 4 is excessively applied to the surface of the main structural member 2, the bonding portion 12 is not formed. For example, in this example, the adhesive 4 is applied to the surface of the main structural member 2 not only at the portion where the bonding portion 12 and the main structural member 2 are in contact, but also at the position of the bonding surface processing portion 11. Since the surface processed portion 11 is processed into a convex shape, the bonding portion 12 is not formed between the surface processed portion 11 and the main structural member 2.

  FIG. 3 is an enlarged view of a cross section taken along line A-A ′ of FIG. 2. The bonding member 99 forms a space having an adhesive surface processed part height D25 and an adhesive surface processed part length L21 in the adhesive surface processed part 11.

  The adhesive surface processed portion height D25 needs to be set so that the adhesive reinforcing member 1 does not contact the main structural member 2 in the adhesive surface processed portion 11 even when a large amount of the adhesive 4 is applied. That is, the thickness of the adhesive in a general structural member is about 0.5 to 1.0 mm, and the thickness of the reinforcing member 1 is 1 mm or more if it is fiber-reinforced resin. In order to ensure this, the bonding surface processed portion height D25 is required to be at least 2 mm, more preferably 5 mm or more.

  On the other hand, if the bonded surface processed part length L21 is too short with respect to the bonded surface processed part height D25, the rigidity of the bonded surface processed part 11 is not sufficiently lowered. For this reason, it is preferable that the bonded surface processed part length L21 is 80% or more with respect to the bonded surface processed part height D25. On the other hand, if the bonded surface processed part length L21 is too long with respect to the bonded surface processed part height D25, further local breakage may occur inside the bonded surface processed part 11 and a significant decrease in strength may occur. There is. Therefore, it is preferable that the bonded surface processed part length L21 is 150% or less with respect to the bonded surface processed part height D25. That is, the bonded surface processed part length L21 is preferably in the range of 80% to 150% with respect to the bonded surface processed part height D25.

  4 illustrates a vertical cross section of the reinforcing member 1 with respect to the longitudinal direction. FIG. 4A is an enlarged view of the cross section taken along the line BB ′ of FIG. 2, and FIG. This is an enlarged view of the cross section at the section. When the bonding surface processed portion height D25 is smaller than the main reinforcing portion height H26, the relative rigidity reduction amount in the bonding surface processed portion 11 is decreased. In order to relatively reduce the rigidity in the bonded surface processed portion 11 and to break it from this portion, the bonded surface processed portion height D25 is preferably set to 30% or more with respect to the main reinforcing portion height H26. . On the other hand, when the bonding surface processed portion height D25 approaches the main reinforcing portion height H26, the rigidity of the reinforcing member 1 in the cross section of the bonding surface processed portion 11 is too low, and there is a possibility that the structure cannot be formed. is there. For this reason, it is preferable to set the bonded surface processed portion height D25 to 80% or less with respect to the main reinforcing portion height H26. That is, it is preferable to set the bonded surface processed part height D25 within a range of 30 to 80% with respect to the main reinforcing part height H26.

  FIG. 5 is a schematic view when the internal wiring 3 is provided between the reinforcing member 1 and the main structural member 2. Conventionally, drive parts and the like are arranged and used by utilizing the space inside the joining member 99, or electrical wiring is laid from the notch portion 13. The same use is possible also by providing.

  6A to 6D show examples of the cross-sectional shape of the bonding surface processed portion 11 in the A-A ′ cross section shown in FIG. 2. For example, when a CFRP cloth material is used, the shape of the bonding surface processed portion 11 is difficult to be formed into a concave / convex shape having a small curvature. Therefore, the shape of (b) or (d) from (a) or (c). However, there is no particular restriction on the cross-sectional shape. In any case, the shape of the bonded surface processed portion may be designed so that the fracture strength of the bonded surface processed portion 11 is lower than the bonded strength of the bonded portion 12.

  The cross-sectional structure of the main reinforcing portion 14 of the reinforcing member 1 does not need to be a trapezoidal structure as shown in this example, and may be a circular arc shape, a double mountain shape, a key shape, or the like. FIG. 7 shows an example of a laminated structure of the reinforcing member 1. In this example, the laminated structure has glass fiber cloth, carbon fiber unidirectional material, and carbon fiber cloth on the surface of aluminum. The reinforcing member 1 is preferably a fiber reinforced resin reinforcing member including at least one type of reinforcing fiber for weight reduction, and more preferably has a single layer of carbon fiber reinforced resin cloth material on the surface. Is desirable from the viewpoint of improving the smoothness of the member surface.

  FIG. 8 is a schematic diagram of the prior art in which the cutout reinforcing member 5 is attached to the main structural member 2. By providing the notch portion 13 in the notch reinforcing member 5, the rigidity in the vicinity of the notch portion 13 is lowered, and the structure is designed to be destroyed. However, since the reinforcing fiber is divided by the notch, the strength of the member at the notch becomes uneven. Furthermore, the structure in which stress is concentrated at the notch portion causes a variation in strength of the structural member.

  The reinforcing member 1 configured by using the present invention can be guided to a position where a fracture position is assumed compared to the conventional structure, that is, a position where the bonding surface processed portion 11 is provided, and the strength variation compared to the conventional technique. Features that can be reduced. Therefore, structural members can be widely used for automobile members, vehicle members, marine members and the like, and in particular, automobile members need to be designed so that a specific portion is bent with respect to the load. It is preferably used for hoods, floor panels, trunk lids, roofs, door panel structures, and the like.

  As the FRP material constituting the reinforcing member 1, it is desirable to have at least one CFRP cloth in the laminated material of the reinforcing member 1. That is, it is assumed that the reinforcing member is broken in the vicinity of the bonding surface processed portion 11 by applying a load in the longitudinal direction of the member. At that time, if the CFRP cloth material is included in the laminate, the damaged material can be stably destroyed without being scattered excessively. Further, the material constituting the main structural member 2 may be a metal material, but the FRP material is preferable because the adhesive strength with the reinforcing member 1 is easily secured.

  Further, although not shown in the drawings, the structure of the reinforcing member 1 and the main structural member 2 of the FRP structural member to which the present invention is applied is not limited to the FRP single plate structure, for example, specific gravity It is also possible to adopt a member configuration in which a small core material is provided and an FRP plate is disposed on one side thereof, or a member configuration (so-called sandwich configuration) in which an FRP plate is disposed on both sides thereof. In such a configuration, the adhesive attachment structure in the present invention as described above may be applied to these FRP plates.

  The structure of the structural member according to the present invention can be applied to any structural member to which a reinforcing member having FRP is attached regardless of a member for an automobile, a member for a vehicle, or a member for a ship.

It is the said schematic which shows the attachment method to the main structural material of the FRP reinforcement member concerning one embodiment of this invention. It is the said schematic which shows the joining member 99 which adhere | attached the reinforcement member made from FRP concerning one embodiment of this invention on the main structural material. FIG. 3 is a schematic cross-sectional view taken along a line AA ′ in the schematic view of FIG. 2. It is the said BB 'cross section of the said schematic drawing of FIG. 2, and the said schematic sectional drawing in CC' cross section. It is a schematic diagram of the internal wiring concerning one embodiment of this invention. FIG. 3 is a design example of a cross section taken along the line AA ′ of the reinforcing member 1 in the schematic diagram of FIG. 2. It is an example of the lamination | stacking design of the cross section in the adhesion surface process part 11 of FIG. It is the said schematic of the prior art which attached the notch reinforcement member 5 to the main structural material 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reinforcement member 2 Main structure material 3 Internal wiring 4 Adhesive 5 Notch reinforcement member 11 Adhesion surface process part 12 Adhesion part 13 Notch part 14 Main reinforcement part 21 Adhesion surface process part length L
25 Bonded surface processed part height D
26 Main reinforcement height H
99 Joining members

Claims (9)

  A structural member in which a reinforcing member made of fiber reinforced resin including reinforcing fibers is attached to a main structural material, wherein the reinforcing member includes at least a convex main reinforcing portion and an adhesive portion, and a part of the adhesive portion A structural member characterized in that a convex bonded surface processed portion is formed.   The longest distance D from the top of the bonded surface processed portion to the main structural material is in a range of 30 to 80% with respect to the longest distance H from the top of the main reinforcing portion to the main structural material, The structural member according to claim 1.   The maximum width L between both ends of the convex protrusion formed as the bonding surface processed portion is in the range of 80 to 150% with respect to the longest distance D from the top of the main reinforcing portion to the main structural material. The structural member according to claim 1 or 2.   The structural member according to any one of claims 1 to 3, wherein the longest distance D from the top of the main reinforcing portion to the main structural member is 5 mm or more.   The structural member according to claim 1, wherein the main structural material is made of a fiber reinforced resin.   The structural member according to any one of claims 1 to 5, wherein the reinforcing member has at least one carbon fiber reinforced resin cloth material.   The structural member according to claim 1, wherein the structural member is an automotive structural member.   The structural member according to claim 7, wherein a use application of the automotive structural member is any one of an automotive hood, a floor panel, a trunk lid, a roof, and a door panel.   The structural member according to claim 1, wherein the structural member is a railcar member or a ship structural member.

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