JP2018095138A - Fixing structure of conductive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing structure of a conductive material which can prevent electric corrosion and can secure temporal reliability even when a resin molding containing carbon fibers and the conductive material are fixed.SOLUTION: A fixing structure includes a resin molding 10 containing carbon fibers, a conductive material 20 which is arranged on one side surface of the resin molding 10 and of which a surface on other side opposite to the resin molding 10 is covered with a first insulator 22, and a blind nut 30 which is inserted in through holes 11, 21 formed on the resin molding 10 and the conductive material 20. The blind nut 30 includes a cylindrical part 31, a flange part 32 positioned on an end part on one side of the cylindrical part 31, and a plastic deformation part 33 which is positioned on an end part on the other side of the cylindrical part 31 and of which a diameter is enlarged by buckling. Outer peripheries of the cylindrical part 31 and the plastic deformation part 33 are covered with a second insulator 35. The resin molding 10 and the conductive material 20 are held by the flange part 32 and the plastic deformation part 33, and a surface on the other side of the flange part 32 is in contact with the conductive material 20.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a conductive material fixing structure.

  Conventionally, a reduction in weight of a vehicle has been demanded in order to improve the fuel efficiency of an automobile. For this reason, vehicles using reinforced plastics as structural materials and panel materials instead of conventional steel plates are known.

  In the above vehicle, reinforced plastic cannot be used as a ground. For this reason, it is known that a conductive material is disposed on a vehicle to form a ground wiring member, and a battery or an auxiliary machine mounted on the vehicle is connected to the ground side terminal (for example, a patent) Reference 1).

  Examples of the reinforced plastic include resin molded products such as CFRP (Carbon Fiber Reinforced Plastics) using carbon fiber as a reinforcing material.

JP, 2006-107874, A

  By the way, when CFRP body panel and grounding material are fixed with metal bolts, CFRP contains carbon fiber. Therefore, if water or the like adheres to the contact points between the bolts and the body panel, electrolytic corrosion occurs on the bolts. Occurs.

  The present invention has been made in view of the above-described circumstances, and its purpose is to prevent the occurrence of electrolytic corrosion even when a resin molded product containing carbon fiber and a conductive material are fixed, and reliability over time. It is in providing the fixing structure of the electrically conductive material which can ensure.

In order to achieve the above-mentioned object, the conductive material fixing structure according to the present invention is characterized by the following (1) to (3).
(1) a resin molded product containing carbon fiber;
A conductive material disposed on a surface on one side in the first direction in the resin molded product;
A metal blind nut inserted into a through-hole penetrating in the first direction formed in the resin molded product and the conductive material;
With
The conductive material has at least a surface on the other side in the first direction facing the resin molded product covered with a first insulator,
The blind nut is
A cylindrical portion extending in the first direction;
A flange portion that is located at an end on the one side of the cylindrical portion and spreads radially outward;
A plastic deformation portion located at the other end of the cylindrical portion and expanded radially outward by buckling; and
Have
The cylindrical part and the outer periphery of the plastic deformation part are covered with a second insulator,
The resin molded product and the conductive material are sandwiched between the flange portion and the plastic deformation portion,
At least a part of the other surface of the flange portion is in contact with the conductive material,
Conductive material fixing structure characterized by the above.
(2) The other end of the blind nut is closed with a lid,
The conductive material fixing structure according to (1) above, wherein
(3) On the surface on the other side of the flange portion, a protruding portion that bites into the conductive material is provided.
The conductive material fixing structure according to the above (1) or (2), wherein

According to the fixing structure of the conductive material having the configuration (1), the resin molded product and the conductive material are securely fixed by being sandwiched between the flange portion and the plastic deformation portion of the blind nut.
Moreover, since the outer periphery of the cylindrical part and plastic deformation part in the blind nut is covered with the second insulator, the resin molded product containing carbon fiber and the metal blind nut are not electrically connected, and the blind It is possible to prevent electrolytic corrosion from occurring on the nut. In addition, since the second insulator that covers the outer periphery of the plastic deformation portion of the blind nut is in close contact with the opening edge on the other side of the through hole of the resin molded product, the cylinder of the through hole and the blind nut It is possible to prevent water from entering the gap between the shape parts, and it is possible to more reliably prevent electrolytic corrosion from occurring in the blind nut. Further, since at least the surface of the conductive material facing the resin molded product is covered with the first insulator, the resin molded product and the conductive material are not electrically connected, and it is possible to prevent galvanic corrosion from occurring in the conductive material. . Therefore, it is possible to provide a conductive material fixing structure that can ensure the reliability over time against electric corrosion.
Furthermore, since at least a part of the flange portion is in contact with the conductive material, the blind nut and the conductive material are electrically connected. Therefore, the blind nut can be used as a connection point for electrically connecting the conductive material. As a result, when a conductive material fixed to a resin molded product (for example, a vehicle body panel) is used as the ground wiring material, the blind nut can be used as a ground point. That is, it is possible to ground the battery and the auxiliary equipment by electrically connecting the ground side terminal of the battery and the auxiliary equipment mounted on the vehicle to the blind nut.
According to the fixing structure of the conductive material having the configuration (2), water can be prevented from entering the blind nut, and electrolytic corrosion can be more reliably prevented from occurring in the blind nut.
According to the fixing structure of the conductive material having the configuration (3), the projection of the flange portion bites into the conductive material by fastening the blind nut, so that the reliability of the electrical connection between the blind nut and the conductive material is further increased. Can be increased. In addition, even when the surface of the conductive material facing the flange portion of the blind nut is covered with the first insulator, the protruding portion of the flange penetrates the first insulator so that the conductive material is interposed via the protruding portion. And the electrical connection between the blind nuts can be secured.

  ADVANTAGE OF THE INVENTION According to this invention, even when fixing the resin molding containing carbon fiber, and a electrically conductive material, it can prevent that an electric corrosion arises and can provide the fixing structure of the electrically conductive material which can ensure temporal reliability.

  The present invention has been briefly described above. Further, the details of the present invention will be further clarified by reading through a mode for carrying out the invention described below (hereinafter referred to as “embodiment”) with reference to the accompanying drawings. .

FIG. 1 is a schematic view showing a fixing structure of a conductive material according to the present embodiment. FIGS. 2A to 2D are diagrams for explaining a buckling process procedure for obtaining the fixing structure shown in FIG. FIG. 3 is a diagram showing an example in which the blind nut included in the conductive material fixing structure shown in FIG. 1 is used as a ground point. FIG. 4 is a schematic diagram illustrating a conductive material fixing structure according to a modification of the present embodiment. FIG. 5 is a schematic view showing a conductive material fixing structure according to another modification of the present embodiment. FIG. 6 is a schematic view illustrating a conductive material fixing structure according to another modification of the present embodiment.

  Specific embodiments relating to the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, the conductive material fixing structure according to the present embodiment includes a resin molded product 10, a conductive material 20, and a blind nut 30. In the following description, the upper side and the lower side in FIG. 1 are referred to as “upper side” and “lower side”, respectively.

  The resin molded product 10 is a molded product of a resin material containing carbon fiber, and is typically a carbon fiber reinforced resin (CFRP) in which a resin is impregnated with carbon fiber as a reinforcing material. Since the resin molded product 10 contains carbon fiber, it has a certain degree of conductivity.

  In this embodiment, the resin molded product 10 constitutes a part of a flat plate portion of a vehicle body panel. In FIG. 1, the upper side and the lower side of the resin molded product 10 correspond to the inner side and the outer side of the vehicle body, respectively. doing. The resin molded product 10 is formed with a through hole 11 penetrating in the vertical direction for inserting the blind nut 30.

  The conductive material 20 is made of, for example, a highly conductive metal material such as copper, copper alloy, or aluminum, and is disposed on the upper side surface of the resin molded product 10. In this example, the conductive material 20 has a flat shape. In the present embodiment, the conductive material 20 is used as a grounding material fixed to the inside of the vehicle body of the body panel.

  The conductive material 20 is formed with a through hole 21 penetrating in the vertical direction for inserting the blind nut 30. The through holes 11 and 21 are coaxially arranged to form one through hole that continuously penetrates in the vertical direction. The surface of the conductive material 20 is covered with a first insulator 22 made of resin or the like except for the peripheral edge of the opening on the upper side of the through hole 21. Thus, since the lower surface of the conductive material 20 is covered with the first insulator 22 over the entire area, the resin molded product 10 and the conductive material 20 are not electrically connected.

  The blind nut 30 is made of metal, and includes a cylindrical portion 31, a flange portion 32, a plastic deformation portion 33, and a female screw portion 34. The cylindrical portion 31 has a cylindrical shape extending in the vertical direction, and is located in the through hole. The flange portion 32 is a flange-shaped portion that is located at the upper end portion of the cylindrical portion 31 and extends radially outward. The lower surface of the flange portion 32 is not covered with the first insulator 22 of the conductive material 20 and is in contact with the upper side surface where the conductive material is exposed.

  The plastic deformation portion 33 is a portion that is located at the lower end portion of the cylindrical portion 31 and has a diameter that is expanded radially outward over the entire circumference by a buckling process described later. That is, the plastic deformation portion 33 is a portion that is a part (lower portion) of the cylindrical portion 31 before the buckling process. The female thread portion 34 is a cylindrical portion that continues to the lower side of the plastic deformation portion 33, and has a female thread 34 a formed on the inner peripheral surface.

  The outer periphery of the cylindrical portion 31 and the plastic deformation portion 33 is covered with a second insulator 35 made of resin or the like over the entire area. The laminate of the resin molded product 10 and the conductive material 20 is sandwiched in the vertical direction by the flange portion 32 and the plastic deformation portion 33. Thereby, the upper side surface of the plastic deformation portion 33 is in close contact with the lower opening edge portion of the through-hole 11 of the resin molded product 10 through the second insulator 35 over the entire circumference.

  In addition, the 2nd insulator 35 located in the outer periphery of the cylindrical part 31 may be in contact with the inner wall of a through-hole, or may not be in contact. Thus, since the outer periphery of the cylindrical part 31 and the plastic deformation part 33 is covered with the 2nd insulator 35 over the whole area, the resin molded product 10 and the blind nut 30 are not electrically connected.

  Next, a buckling process procedure for obtaining a conductive material fixing structure according to an embodiment of the present invention will be described with reference to FIG.

  First, as shown in FIG. 2 (a), the blind nut 30 in which the plastic deformation portion 33 is not yet formed in the through hole of the laminate of the resin molded product 10 and the conductive material 20, and the flange portion 32 is positioned on the upper side. Insert it from the top in the direction you want. In addition, the blind nut 30 before the buckling treatment includes a flange portion 32, a cylindrical portion 31, and a female screw portion 34 in order from the upper side, and only the cylindrical portion 31 is covered with the second insulator 35.

  Next, as shown in FIG. 2B, a buckling male screw 40 having a head 41 is inserted into the blind nut 30 from above, and the male screw 40 is inserted into the female screw portion 34 of the blind nut 30. In a state where the screw 34a is screwed, the male screw 40 is rotated in one direction to advance downward.

  As shown in FIG. 2 (c), the rotation of the male screw 40 in one direction, that is, the downward movement is continued even after the head portion 41 contacts the flange portion 32. As a result, in the blind nut 30, a stress in a direction that brings the flange portion 32 and the female screw portion 34 close to each other in the vertical direction acts. This stress acts as a buckling stress that buckles the lower portion of the cylindrical portion 31 located below the lower surface of the resin molded product 10.

  As a result, a portion of the cylindrical portion 31 located below the lower surface of the resin molded product 10 is expanded radially outward over the entire circumference to become the plastic deformation portion 33, and the resin molded product 10 and the conductive material are electrically conductive. A laminate of the material 20 is sandwiched in the vertical direction by the flange portion 32 and the plastic deformation portion 33.

  And as shown in FIG.2 (d), the external thread 40 is taken out from the blind nut 30 by rotating the external thread 40 to the other direction opposite to one direction, and making it advance upwards. Thus, the buckling process is completed, and the conductive material fixing structure shown in FIG. 1 is obtained.

  As described above, according to the conductive material fixing structure according to the embodiment of the present invention, the resin molded product 10 and the conductive material 20 are sandwiched between the flange portion 32 and the plastic deformation portion 33 of the blind nut 30. Securely fixed.

  Moreover, since the outer periphery of the cylindrical part 31 and the plastic deformation part 33 in the blind nut 30 is covered with the second insulator 35, the resin molded product 10 containing carbon fiber and the metal blind nut 30 are electrically connected. Not connected to. Therefore, electric corrosion can be prevented from occurring in the blind nut 30. In addition, the second insulator 35 covering the outer periphery of the plastic deformation portion 33 of the blind nut 30 is in close contact with the lower opening edge of the through hole 11 of the resin molded product 10 over the entire periphery. Therefore, water can be prevented from entering the gap between the through-hole and the cylindrical portion 31 of the blind nut 30 from the outside of the vehicle body, and this can also prevent electrolytic corrosion from occurring in the blind nut 30. Furthermore, since at least the surface (lower surface) facing the resin molded product 10 in the conductive material 20 is covered with the first insulator 22, neither the resin molded product 10 nor the conductive material 20 is electrically connected. It is also possible to prevent electrolytic corrosion from occurring at 20. Therefore, it is possible to provide a conductive material fixing structure that can ensure the reliability over time against electric corrosion.

  Furthermore, since the lower surface of the flange portion 32 is in contact with the conductive material 20, the blind nut 30 and the conductive material 20 are electrically connected. Therefore, the blind nut 30 can be used as a connection point that is electrically connected to the conductive material 20. As a result, when the conductive material 20 fixed to the resin molded product 10 (the vehicle body panel in the present embodiment) is used as a grounding material, the blind nut 30 is grounded as shown in FIG. Can be used as a point.

  In the example shown in FIG. 3, the battery side mounted on the vehicle and the ground side terminal W of the auxiliary machinery are electrically connected to the blind nut 30 by the male screw 50 having the head 51 and the nut 60 screwed to the male screw 50. Has been. This makes it possible to ground the battery and auxiliary equipment. In the example shown in FIG. 3, the female screw portion 34 is cut and removed.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably. In addition, the material, shape, dimensions, number, arrangement location, and the like of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.

  For example, in the above embodiment, the entire lower surface of the flange portion 32 is in contact with the conductive material 20 (see FIG. 1), but as shown in FIG. 4, a protrusion that bites into the conductive material 20 on the lower surface of the flange portion 32. The part 32a may be provided. The protrusion 32a bites into the upper surface of the conductive material 20 during the above-described buckling stress action. Thereby, the reliability of the electrical connection between the blind nut 30 and the conductive material 20 can be further enhanced.

  As described above, when the protrusion 32a is provided on the lower surface of the flange portion 32, as shown in FIG. 5, the surface of the conductive material 20 facing the lower surface of the flange portion 32 (the through hole 21 of the conductive material 20). Even when the upper surface of the upper opening is covered with the first insulator 22, the protrusion 32a penetrates through the first insulator 22, so that the conductive material 20 and the blind are interposed through the protrusion 32a. An electrical connection with the nut 30 can be ensured.

  Moreover, in the said embodiment, although the lower end part (lower end part of the internal thread part 34) of the blind nut 30 is opening as shown in FIG. 1, the lower end part (internal thread part) of the blind nut 30 is shown in FIG. 34) may be closed with a lid 36. Thereby, it is possible to prevent water from entering the inside of the blind nut 30 from the outside of the vehicle body, and more reliably prevent electrolytic corrosion from occurring in the blind nut 30.

  Moreover, in the said embodiment, although the resin molded product 10 is a CFRP molded product, if it is resin containing carbon fiber, it may be a molded product of what kind of material. In addition, both the resin molded product 10 and the conductive material 20 have a flat plate shape, but either one or both of the resin molded product 10 and the conductive material 20 may have a shape other than the flat plate shape. .

Here, the features of the embodiment of the conductive material fixing structure according to the present invention described above are summarized and listed in the following [1] to [3], respectively.
[1] A resin molded product (10) containing carbon fiber;
A conductive material (20) disposed on one surface in the first direction of the resin molded product (10);
A metal blind nut (30) inserted through the resin molded product (10) and the through holes (11, 21) penetrating in the first direction formed in the conductive material (20);
With
The conductive material (20) is covered with a first insulator (22) at least on the other surface in the first direction facing the resin molded product (10),
The blind nut (30)
A cylindrical portion (31) extending in the first direction;
A flange portion (32) located at an end of the one side of the cylindrical portion (31) and extending radially outward;
A plastic deformation portion (33) located at the other end of the cylindrical portion (31) and expanded radially outward by buckling; and
Have
The cylindrical part (31) and the outer periphery of the plastic deformation part (33) are covered with a second insulator (35),
The resin molded product (10) and the conductive material (20) are sandwiched between the flange portion (32) and the plastic deformation portion (33),
At least a part of the other surface of the flange portion (32) is in contact with the conductive material (20).
Conductive material fixing structure characterized by the above.
[2] The other end of the blind nut (30) is closed by a lid (36).
The conductive material fixing structure according to [1] above, wherein the conductive material is fixed.
[3] On the other surface of the flange portion (32), a protrusion (32a) that bites into the conductive material (20) is provided.
The conductive material fixing structure according to the above [1] or [2], wherein the conductive material is fixed.

DESCRIPTION OF SYMBOLS 10 Resin molding 11 Through-hole 20 Conductive material 21 Through-hole 22 1st insulator 30 Blind nut 31 Cylindrical part 32 Flange part 32a Protrusion part 33 Plastic deformation part 35 2nd insulator 36 Lid part

Claims (3)

Resin molded products containing carbon fiber;
A conductive material disposed on a surface on one side in the first direction in the resin molded product;
A metal blind nut inserted into a through-hole penetrating in the first direction formed in the resin molded product and the conductive material;
With
The conductive material has at least a surface on the other side in the first direction facing the resin molded product covered with a first insulator,
The blind nut is
A cylindrical portion extending in the first direction;
A flange portion that is located at an end on the one side of the cylindrical portion and spreads radially outward;
A plastic deformation portion located at the other end of the cylindrical portion and expanded radially outward by buckling; and
Have
The cylindrical part and the outer periphery of the plastic deformation part are covered with a second insulator,
The resin molded product and the conductive material are sandwiched between the flange portion and the plastic deformation portion,
At least a part of the other surface of the flange portion is in contact with the conductive material,
Conductive material fixing structure characterized by the above. The other end of the blind nut is closed with a lid,
The structure for fixing a conductive material according to claim 1. On the surface on the other side of the flange portion, a protrusion that bites into the conductive material is provided,
The conductive material fixing structure according to claim 1, wherein the conductive material is fixed.

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