JP2010240930A - Fitting structure of fiber-reinforced composite material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fitting structure of a fiber-reinforced composite material which can directly fasten of composite material to the other member while suppressing the creep of the composite material. <P>SOLUTION: The fiber-reinforced composite material 1 is superposed on a metallic material 2 and the superposed materials are fastened with a nut 19 by bringing a washer 16 at the head side of a bolt 14 being a fastening means into contact with the surface 11 of an exposed bias thread 7. Fastening forces of the bolt 14 and the nut 19 are applied to a contact part between the washer 16 and the surface 11 of the bias thread 7, a contact part between the lower surface 12 of the fiber-reinforced composite material 1 and the upper surface 13 of the metallic material 2, and a contact part between the lower surface of the metallic material 2 and a washer 18. Consequently, because of the absence of an epoxy resin layer of the upper layer, otherwise to be formed on the upper surface of the metallic material, the fastening force applied concentrically to the fiber-reinforced composite material 1 is directly received by the bias thread 7, and large stress is not generated in an epoxy resin 4 which is present in the fiber-reinforced composite material 1. Thus, the creep of the epoxy resin 4 can be suppressed thus eliminating a slack between the fiber-reinforced composite material 1 and the metallic material 2, and accordingly, maintaining a rigid fastening state. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a structure for attaching a fiber reinforced composite material in which a fiber reinforced composite material using a resin as a matrix is fastened to another member.

  The fiber reinforced composite material is formed by impregnating a reinforcing fiber layer with a resin as a matrix and may be used by being attached to another member by fastening means such as bolts and nuts. The fiber reinforced composite material attached to another member has a problem in that it is difficult to firmly attach the fiber reinforced composite material because the resin creep occurs due to the fastening force and loosens between the other members. In order to solve such a problem in attaching the fiber reinforced composite material, generally, for example, an attachment method using a metal pipe as disclosed in Patent Document 1 is often used.

  Patent Document 1 discloses a structure in which a housing including a rotation detection device is attached to an in-vehicle engine. The housing is resin-molded together with a flange for mounting to the vehicle-mounted engine. A metal pipe is inserted into and integrated with the bolt insertion hole of the flange by insert molding. The housing is attached by fastening a bolt passed through the metal pipe to a female screw of the in-vehicle engine.

  Therefore, since the fastening force of the bolt acts only on the metal pipe and does not hang on the flange formed of the resin material, it is possible to solve the problem of loosening due to the resin creep described above. As a means for integrating the metal pipe into the bolt insertion hole of the flange, a method of press-fitting the metal pipe into the bolt insertion hole after molding is generally used in addition to the insert molding.

JP 2006-275270 A

  As in Patent Document 1, the method of integrating the metal pipe into the bolt insertion hole requires high mounting accuracy of the metal pipe. For example, when a metal pipe is insert-molded into the flange, as in the invention of Patent Document 1, a high-precision molding technique is performed so that no resin is interposed between the end surface of the metal pipe, the head of the bolt, and the vehicle-mounted engine. Need. In the method of press-fitting a metal pipe into a bolt insertion hole, since it is necessary to increase the accuracy of the bolt insertion hole and the press-fitting accuracy of the metal pipe, the number of processing steps increases and the processing work becomes complicated. In addition, the use of metal pipes leads to an increase in weight, which also hinders the advantage of weight reduction by the resin material.

  The present invention provides an attachment structure for a fiber-reinforced composite material that can be directly fastened to another member while suppressing creep of the fiber-reinforced composite material.

  The present invention according to claim 1 is a fiber-reinforced composite material mounting structure in which a fiber-reinforced composite material formed by impregnating a reinforcing fiber layer with a resin is attached to another member by fastening means. It has a reinforcing fiber layer exposed to the region where the fastening means comes into contact, and the fastening means is brought into contact with the exposed reinforcing fiber layer and fastened.

  According to this invention of Claim 1, since the fastening force of a fastening means can be received by a reinforced fiber layer, the loosening of the fastening of the fiber reinforced composite material by creep can be prevented with a simple structure.

  The invention of claim 2 is characterized in that the reinforcing fiber layer is exposed by removing the resin layer on the surface of the fiber reinforced composite material. It can be easily and reliably exposed.

  The present invention according to claim 3 is characterized in that the resin layer on the surface is removed by laser processing, so that only the resin layer in the surface region of the fiber-reinforced composite material is removed without damaging the reinforcing fibers. be able to.

  The present invention according to claim 4 is characterized in that the resin layer on the surface is removed by grinding, so that the apparatus for removing the resin layer of the fiber reinforced composite material can be simplified.

  Since the present invention according to claim 5 is characterized in that the reinforcing fiber layer is composed of carbon fibers, there is a large difference in the melting temperature of the carbon fibers and the resin. It becomes free and the processing device can be simplified.

  The present invention according to claim 6 is characterized in that the fiber reinforced composite material has a structure in which a resin is impregnated into a three-dimensional woven fabric. Can be prevented and the range of use of the fiber-reinforced composite material can be expanded.

  The present invention can suppress creep with a simple configuration and prevent loosening at the time of fastening of the fiber-reinforced composite material.

Sectional drawing which shows the attachment structure of the fiber reinforced composite material and other member in 1st Embodiment. Sectional drawing which shows the fiber reinforced composite material after shaping | molding. Sectional drawing of the fiber reinforced composite material which shows the removal method of a resin layer. Sectional drawing of the fiber reinforced composite material which removed the resin layer. Sectional drawing which shows the attachment structure of the fiber reinforced composite material and other member in 2nd Embodiment.

(First embodiment)
A first embodiment will be described with reference to FIGS. FIG. 1 shows an attachment structure in which a fiber reinforced composite material 1 used as a structural material in, for example, an automobile or an aircraft is fastened to a metal material 2 as another member. In the present specification, for the sake of convenience, the state of FIG. 1 is assumed to be the front, the vertical direction is the upper side, the lower side, and the left-right direction is the left side and the right side.

  The fiber reinforced composite material 1 is formed by impregnating a three-dimensional fabric 3 using carbon fibers with an epoxy resin 4. The three-dimensional woven fabric 3 has a known structure, and is arranged perpendicular to the orientation direction of the warp 5, the weft 6, the warp 5, the bias yarn 7 arranged obliquely with respect to the weft 6, and the warp 5 or weft 6. It is constituted by a vertical thread 8. The warp yarns 5, weft yarns 6 and bias yarns 7 are alternately laminated in a state of being closely arranged on a plane, and the warp yarns 5, weft yarns 6 and bias yarns 7 are laminated in a designed thickness. . In this embodiment, each of the warp 5, the weft 6, and the bias yarn 7 forms a reinforcing fiber layer. The laminated warp yarn 5, weft yarn 6 and bias yarn 7 are formed on the bias yarn 7 side while weaving continuous vertical yarn 8 from the warp yarn 5 side forming the lower surface layer to the bias yarn 7 side forming the upper surface layer. The vertical thread 8 is integrated by locking the loop portion 9 with the ear thread 10. The vertical yarn 8 is oriented in a direction perpendicular to the lower warp yarn 5 between the weaving positions, and the ear yarn 10 is oriented in a direction crossing the bias yarn 7 so as not to fall off.

  The epoxy resin 4 is impregnated into the three-dimensional fabric 3 as a matrix, fills the inside of the three-dimensional fabric 3, and covers the entire outer surface except the surface 11 of the bias yarn 7 located in the uppermost layer to form a resin layer. ing. The fiber reinforced composite material 1 shown in FIG. 1 has a configuration including a bias yarn 7 having a surface 11 exposed, that is, a reinforcing fiber layer exposed.

  The fiber reinforced composite material 1 is attached to the metal material 2 as follows. The lower surface 12 of the fiber reinforced composite material 1 covered with the epoxy resin 4 is superposed on the upper surface 13 of the metal material 2. The bolt 14 as a fastening means is inserted from the side of the through hole 15 formed in the fiber reinforced composite material 1 and comes into contact with the surface 11 of the bias yarn 7 where the washer 16 on the head side of the bolt 14 is exposed. The front end of the bolt 14 passes through a through-hole 17 formed in the metal material 2 and projects downward from the metal material 2 and is tightened by a nut 19 as a fastening means via a washer 18.

  In attaching the fiber reinforced composite material 1, the fastening force of the bolt 14 and the nut 19 is such that the contact portion between the washer 16 and the surface 11 of the bias yarn 7, the lower surface 12 of the fiber reinforced composite material 1, and the upper surface 13 of the metal material 2. It is added to the contact portion and the contact portion between the lower surface of the metal material 2 and the washer 18. The fastening force applied intensively to the fiber reinforced composite material 1 through the washer 16 is directly received by the bias yarn 7 because there is no epoxy resin 4a layer (see FIG. 2) that forms the upper surface of the fiber reinforced composite material 1. A large stress is not generated in the epoxy resin 4 existing inside the fiber reinforced composite material 1. Accordingly, the large creep that occurs in the layer of the epoxy resin 4a that originally forms the upper surface is eliminated, and the creep of the epoxy resin 4 existing inside is suppressed. Since the layer of the epoxy resin 4 forming the lower surface 12 of the fiber reinforced composite material 1 is in contact with the upper surface 13 of the metal material 2 over a wide range, the fastening force is dispersed, and the stress generated in the epoxy resin 4 is a problem. The size is such that it cannot be.

  The fiber reinforced composite material 1 shown in FIG. 1 is formed by the manufacturing method shown in FIGS. FIG. 2 shows the fiber-reinforced composite material 1 after molding. As described above, the fiber reinforced composite material 1 is formed by impregnating the epoxy resin 4 in the three-dimensional fabric 3. The epoxy resin 4 fills the inside of the three-dimensional fabric 3 and covers the entire outer surface of the three-dimensional fabric 3. In addition, the layer of the epoxy resin which coat | covers the upper surface of the fiber reinforced composite material 1 is shown with the code | symbol 4a for convenience of explanation.

  The fiber reinforced composite material 1 in FIG. 2 is processed by a YAG laser (yttrium aluminum garnet laser) 20 disposed above the fiber reinforced composite material 1, as shown in FIG. The YAG laser 20 is disposed so as to be movable from the left end side to the right end side of the fiber reinforced composite material 1 by appropriate means, and can emit laser light 21 toward the fiber reinforced composite material 1. The moving direction of the YAG laser 20 is set so as to be movable from the front side to the back side in FIG. The moving operation and the light emitting operation of the YAG laser 20 are operated by a control device (not shown). The energy of the laser beam 21 and the moving speed of the YAG laser 20 are set in advance to values suitable for melting and evaporation of the epoxy resin 4. For example, when the energy of the laser beam 21 is large, it can be set to increase the moving speed of the YAG laser 20, and the processing time can be shortened. On the other hand, when the energy of the laser beam 21 is small, the moving speed of the YAG laser 20 can be set slower, which can contribute to a reduction in energy consumption.

  The YAG laser 20 starts moving from the left end side of the fiber reinforced composite material 1 and emits a laser beam 21 in accordance with a command from the control device. The laser beam 21 is applied to the layer of the epoxy resin 4a that forms the upper surface of the fiber reinforced composite material 1, and the epoxy resin 4a is melted and evaporated to be sequentially removed. The carbon fiber does not transmit the laser beam 21, and the melting temperature is higher than that of the epoxy resin 4a. For this reason, the laser beam 21 can remove only the epoxy resin 4 a on the upper surface of the fiber reinforced composite material 1 and expose the surface 11 of the bias yarn 7 forming the surface layer of the three-dimensional fabric 3.

  As shown in FIG. 4, the fiber-reinforced composite material 1 that has been laser-processed as shown in FIG. 3 is subjected to drilling. The fiber reinforced composite material 1 from which the surface 11 of the bias yarn 7 is exposed is drilled by a drilling machine such as a drilling machine (not shown) or a tool such as a drill, and a fastening through hole 15 is formed at one predetermined position or Drilled in multiple places. The fiber-reinforced composite material 1 manufactured by the above method is fastened by the bolt 14 and the nut 19 and attached to the metal material 2 as described in FIG.

The first embodiment described above has the following operational effects.
(1) The head side of the bolt 14 on which the fastening force by the bolt 14 and the nut 19 is concentrated on the fiber reinforced composite material 1 is in direct contact with the surface 11 of the bias yarn 7 via the washer 16. The fiber reinforced composite material 1 is firmly fixed to the metal material 2 by the fastening force. This fastening force is received by the bias yarn 7 and is greatly applied to the epoxy resin 4 filled in the fiber reinforced composite material 1. Does not cause stress. For this reason, the creep by the layer of the epoxy resin 4a that originally forms the upper surface of the fiber reinforced composite material 1 is completely eliminated and the creep of the epoxy resin 4 existing inside is suppressed, and the fiber reinforced composite material 1 and the metal material 2 are suppressed. It is possible to prevent loosening due to creep.

(2) Since the fiber reinforced composite material 1 can be directly fastened to the metal material 2, there is no need to increase the accuracy for attaching the fiber reinforced composite material 1 as in the prior art, and a separate member such as a metal pipe is used. Since there is no need to intervene, the configuration is simplified, which can contribute to weight reduction.
(3) By using carbon fiber for the reinforcing fiber layer, laser processing becomes easy, and only the layer of the epoxy resin 4a can be easily removed without damaging the reinforcing fiber layer made of the bias yarn 7. In addition, since a large difference in melting temperature between the carbon fiber and the resin can be used, the type of laser and energy can be easily selected, and the processing apparatus can be simplified.
(4) Since the fiber reinforced composite material 1 whose strength is increased by using the three-dimensional fabric 3 can be directly fastened to another member, the versatility of the fiber reinforced composite material 1 can be enhanced.

(Second Embodiment)
The second embodiment shown in FIG. 5 is a modification of the method for removing the layer of the epoxy resin 4a and the region to be removed in the first embodiment. The same reference numerals are used for the same components as those in the first embodiment. A detailed description will be omitted.

  In the fiber reinforced composite material 1 shown in the second embodiment, the epoxy resin 4a layer is removed only in a region S slightly wider than the washer 16 on the head side of the bolt 14. The region S is set to a narrow range within the pitch interval of the ear thread 10. Although not shown, the layer of the epoxy resin 4a in the region S is removed by counterbore processing using a general grinding machine, and the surface 11 of the bias yarn 7 is exposed. In particular, the present embodiment does not affect the strength of the fiber-reinforced composite material 1 because the vertical yarn 8 and the ear yarn 10 are not damaged.

  Also in the second embodiment, since the washer 16 on the head side of the bolt 14 is in direct contact with the surface 11 of the bias yarn 7, the creep of the epoxy resin 4 is suppressed as in the first embodiment, and the fiber It is possible to prevent loosening of the bolt that fastens the reinforced composite material 1 to the metal material 2. Since the layer of the epoxy resin 4a is removed using a general grinding machine, the processing apparatus can be simplified.

  The present invention is not limited to the configuration of each of the embodiments described above, and various modifications are possible within the scope of the gist of the present invention, and can be implemented as follows.

(1) In the fiber reinforced composite material 1, if the region where the reinforcing fiber layer indicated by the bias yarn 7 is exposed includes at least the region where the fastening means indicated by the bolt and nut contacts, the first and second It is possible to set without being limited to the area of the embodiment.
(2) In 1st Embodiment, the layer of the epoxy resin 4 which forms the lower surface 12 of the fiber reinforced composite material 1 is removed, the surface of the warp 5 which is a reinforced fiber layer is exposed, and the exposed warp 5 is made into a metal material. 2 can be brought into direct contact with the upper surface 13 and fastened. If comprised in this way, all the fastening force concerning the fiber reinforced composite material 1 can be received with a reinforced fiber layer, and the inhibitory effect of the creep in the epoxy resin 4 can be improved more.
(3) In the second embodiment, the layer of the epoxy resin 4a in the region S can be removed by the YAG laser 20 shown in the first embodiment.
(4) In the first and second embodiments, in order to increase the strength of the fiber reinforced composite material 1, the density of weaving the vertical yarn 8 is increased, and the washer 16 on the head side of the bolt 14 is connected to the vertical yarn 8. The form which contacts may be sufficient. In this case, when the epoxy resin 4a is ground as in the second embodiment, the loop portion 9 and the ear yarn 10 of the vertical yarn 8 may be cut. However, the strength of the fiber reinforced composite material 1 does not decrease because the other yarn groups constituting the three-dimensional fabric 3 are bonded by the epoxy resin 4.

(5) In the first embodiment, the laser processing means is not limited to the YAG laser 20, and other solid lasers such as ruby lasers, gas lasers such as carbon dioxide gas lasers, liquid lasers, semiconductor lasers, and the like can be used.
(6) The reinforcing fiber layer in the fiber reinforced composite material 1 is not limited to the three-dimensional fabric 3 and can be formed by the following method. The vertical yarn 8 and the ear yarn 10 of the three-dimensional fabric 3 can be used, that is, the warp yarn 5, the weft yarn 6, and the bias yarn 7 can be laminated. In this case, the direction of the yarns densely arranged on the plane is not limited to the longitudinal direction, the lateral direction, and the bias direction, as long as the direction is the same direction on the same plane. Further, any one of the warp yarn 5, the weft yarn 6 and the bias yarn 7 may be laminated and formed, or two types of yarns may be alternately laminated. Further, it can be formed by laminating plane fabrics woven with warps 5 and wefts 6. In addition, it can form by laminating a nonwoven fabric.

(7) In the first embodiment, the reinforcing fiber layer may be formed using glass fiber. In this case, since the YAG laser 20 may transmit the laser light 21 through the glass fiber, it is preferable to use a laser that emits light in an energy region that does not transmit through other glass fibers, such as a carbon dioxide gas laser.
(8) The reinforcing fiber layer may be formed using boron fiber, aramid fiber, polyethylene fiber, xylon, or the like in addition to the above-described carbon fiber or glass fiber.
(9) The matrix of the fiber reinforced composite material 1 is not limited to the epoxy resin 4, and other thermosetting resins and thermoplastic resins can be used.
(10) The manufacturing method of the fiber reinforced composite material 1 having the reinforced fiber layer that is exposed is a laser of the epoxy resin 4a layer of the fiber reinforced composite material 1 after molding as in the first and second embodiments. Not only the method of removing by processing or grinding, but the following method can be adopted. That is, the molding of the fiber reinforced composite material 1 uses a molding die having a protrusion that can contact the reinforcing fiber layer. Since the resin injected into the mold does not turn to the contact portion between the reinforcing fiber layer and the protruding portion of the mold, the fiber-reinforced composite material 1 having the exposed reinforcing fiber layer is molded, and the processing steps after molding Can be eliminated.

(11) The fastening means between the fiber reinforced composite material 1 and the metal material 2 is not limited to bolts and nuts, but may be a form in which a female screw is formed in the through hole 17 of the metal material 2 and a male screw of the bolt 14 is screwed. In this case, the through hole 17 may have a bottom. In these methods, the hole does not necessarily have to be formed in the fastening portion of the fiber reinforced composite material 1. Further, for example, a means such as a vise or a pinching mechanism can be used as the fastening means according to other members. When these fastening means are used, it is not necessary to form the through hole 15 of the fiber reinforced composite material 1 and the through hole 17 of the metal material 2, and the number of manufacturing steps of the fiber reinforced composite material 1 can be reduced.
(12) Other members to which the fiber reinforced composite material 1 is attached include not only metal materials 2 and non-metallic materials constituting automobiles, aircrafts, or other structures, but also wall surfaces and floor surfaces of buildings and earth or rocks. included. Further, the other member made of a non-metallic material may be a fiber reinforced composite material.

DESCRIPTION OF SYMBOLS 1 Fiber reinforced composite material 2 Metal material 3 Three-dimensional fabric 4 Epoxy resin 5 Warp yarn 6 Weft yarn 7 Weft yarn 8 Vertical yarn 10 Ear yarn 14 Bolt 15, 17 Through hole 16, 18 Washer 19 Nut 20 YAG laser 21 Laser light S area | region

Claims (6)

In the fiber-reinforced composite material mounting structure in which the fiber-reinforced composite material formed by impregnating the reinforcing fiber layer with resin is attached to other members by fastening means.
A fiber having a reinforcing fiber layer exposed in at least a region of the fiber-reinforced composite material in contact with the fastening means, and fastened by bringing the fastening means into contact with the exposed reinforcing fiber layer. Reinforced composite mounting structure.   The fiber reinforced composite attachment structure according to claim 1, wherein the reinforcing fiber layer is exposed by removing a resin layer on a surface of the fiber reinforced composite material.   The fiber reinforced composite attachment structure according to claim 2, wherein the resin layer on the surface is removed by laser processing.   The fiber reinforced composite attachment structure according to claim 2, wherein the resin layer on the surface is removed by grinding.   The fiber reinforced composite material mounting structure according to any one of claims 1 to 4, wherein the reinforcing fiber layer is made of carbon fiber.   The fiber reinforced composite material mounting structure according to any one of claims 1 to 5, wherein the fiber reinforced composite material has a structure in which a three-dimensional fabric is impregnated with a resin.