JP2006019324A - Structure and method for fixing flexible flat circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure and a method for fixing flexible flat circuits such as an FPC (Flexible Printed Circuits), an FFC (Flexible Flat Cable) or the like to the fixing part of vehicle body or the like by which manufacturing cost can be greatly reduced. <P>SOLUTION: A projection 10 is penetrated into a first fixing hole 23 of an FPC 20, and then a branching piece 22 is folded and the projection 10 is penetrated into the large-diameter part 25 of a second fixing hole 24. Furthermore, the branching piece 22 is slid parallel to the main body 21 of the FPC, and the stem 11 of the projection 10 is inserted into the small-diameter part 26 of the second fixing hole 24. Thus, the FPC 20 can be prevented from dropping out from the projection 10 of the first fixing hole 23. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a structure and method for attaching a flexible flat circuit such as FPC (Flexible Printed Circuits), FFC (Flexible Flat Cable), etc. to a fixed part of an automobile body or the like.

Conventionally, as a method of attaching a flexible flat circuit such as FPC or FFC mounted on an automobile or the like to a fixing portion such as an automobile body, for example, a protrusion protruding from the fixing side is inserted into an attachment hole provided in the FPC, A method of fixing the tip of the protrusion protruding from the mounting hole by welding (Patent Document 1), a method of fixing a metal fixing member to the FPC by welding, soldering, etc. (Patent Document 2), an FPC made of resin A method (Patent Document 3) or the like that is sandwiched between clips and attached to a fixed portion via a clip is known.
JP 2002-151867 A, paragraph 0013, FIG. JP 2002-164624 A, paragraph 0015, FIG. JP 2002-204082 A, paragraph 0014, FIG.

  However, among the conventional flexible flat circuit mounting structures described above, in the method disclosed in Patent Document 1, the FPC must be attached to the fixing portion by thermally attaching the tip of the protrusion. Special tools and work for wearing are required. In addition, the mounting operation is difficult at the position where the vehicle body is deep.

  In the method disclosed in Patent Document 2, a fixing member needs to be provided separately, and a dedicated tool and work for fixing the fixing member to the FPC by welding, soldering, or the like are required.

  In the method disclosed in Patent Document 3, it is necessary to separately facilitate a clip, which is a resin component for attachment to the fixed portion, and an operation for attaching the clip to the FPC is required.

  The present invention has been made in view of the above circumstances, and has a flexible flat circuit mounting structure and mounting method that do not require a special dedicated tool and can achieve a significant reduction in parts cost and manufacturing cost. The purpose is to provide.

  In the flexible flat circuit mounting structure according to the present invention, the flexible flat circuit is fixed to the fixing portion by attaching the flexible flat circuit to the protrusion protruding from the fixing side. A flat circuit mounting structure, wherein the protrusion projecting on the fixed side has a trunk portion and an enlarged diameter portion larger in diameter than the trunk portion formed at the tip of the trunk portion, and the flexible flat circuit Is a flexible flat circuit main body in which a first mounting hole having a diameter substantially equal to or slightly larger than the diameter-expanded portion of the protrusion is formed, and the diameter is increased by branching from the flexible flat circuit main body. A gourd-type second integrated with a large-diameter portion having a diameter substantially the same as or slightly larger than the diameter portion and a small-diameter portion having a diameter smaller than that of the enlarged-diameter portion and substantially the same diameter or slightly larger than the trunk portion. And a branch piece formed with an attachment hole, and the first attachment hole of the flexible flat circuit body In the state where the projection is penetrated, the branch piece is folded and the trunk portion of the projection penetrated through the large diameter portion of the second mounting hole is fitted in the small diameter portion of the second mounting hole, The protrusion is prevented from coming off from the flexible flat circuit.

  In the flexible flat circuit mounting method according to the present invention, the flexible flat circuit may be fixed to the fixing portion by attaching the flexible flat circuit to a protrusion protruding on the fixing side. A method for attaching a flexible flat circuit, wherein the protrusion projecting on the fixed side includes a trunk part and an enlarged diameter part larger in diameter than the trunk part formed at the tip of the trunk part, and A flexible flat circuit is branched from the flexible flat circuit main body in which a first mounting hole having a diameter substantially equal to or slightly larger than the diameter-expanded portion of the protrusion is formed. A gourd in which a large-diameter portion that is substantially the same diameter as or slightly larger in diameter than the enlarged-diameter portion and a small-diameter portion that is smaller in diameter than the enlarged-diameter portion and substantially the same diameter or slightly larger in diameter than the trunk portion And a branch piece formed with a second mounting hole of the mold. After the protrusion is passed through the first mounting hole of the rat circuit body, the branch piece is folded back to pass the protrusion through the large-diameter portion of the second mounting hole, and the branch piece is further flexible. The stem of the projection is inserted into the small diameter portion of the second mounting hole by sliding in parallel with the flat circuit main body, thereby preventing the first mounting hole from coming off from the projection. It is characterized by that.

  As one embodiment of the present invention, the flexible flat circuit main body and the branch piece have the first attachment hole and the second attachment hole in a direction orthogonal to the branch direction of the branch piece, respectively. Two each may be formed.

  As another embodiment, the branch piece is formed with an auxiliary branch piece that further branches in a direction orthogonal to the branch direction, and the auxiliary branch piece has substantially the same diameter as the diameter-expanded portion or slightly A gourd-type in which a large-diameter portion and a small-diameter portion having a diameter smaller than that of the enlarged-diameter portion and substantially the same as or slightly larger than the enlarged-diameter portion are integrated in a direction perpendicular to the second mounting hole. A trunk portion of the projection formed through a large diameter portion of the third mounting hole by forming the third mounting hole and folding the auxiliary branch piece in a state where the branch piece is attached to the projection. May be fitted in the small diameter portion of the third mounting hole.

  In another embodiment, peripheral portions of the first mounting hole and the second mounting hole are reinforced by metal lands.

  In still another embodiment, a fold is formed at the tip of the branch piece, and the tip bent along the fold is folded under the flexible flat circuit, or the branch. A fold is formed in the folded portion of the piece.

  According to the present invention, after the protrusion is passed through the first mounting hole of the flexible flat circuit body, the branch piece is folded back, the protrusion is passed through the large diameter portion of the second mounting hole, and the branch piece is further attached. Since the stem of the projection is inserted into the small diameter portion of the second mounting hole by sliding in parallel with the flexible flat circuit main body, the first mounting hole is prevented from coming off from the projection. The flexible flat circuit can be stably attached to the fixing portion without requiring a special attachment member, a tool for attachment, and work. Thereby, the manufacturing cost can be significantly reduced.

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

  FIG. 1 is a perspective view of an essential part for explaining a flexible flat circuit mounting structure and mounting method according to a first embodiment of the present invention.

  As shown in FIG. 1A, a resin-made projection 10 is formed on a fixing portion such as an automobile door trim (not shown). The protrusion 10 is formed by integrally forming a trunk portion 11 and an enlarged diameter portion 12 having a larger diameter than the trunk portion 11 formed at the tip of the trunk portion 11. An FPC (or FFC) 20 as a flexible flat circuit fixed to the protrusion 10 is a band-shaped FPC main body 21 extending in a predetermined direction, and is orthogonal to the longitudinal direction of the FPC main body 21 from the FPC main body 21. And a branch piece 22 that branches in the direction. The FPC main body 21 is formed with a first attachment hole 23 having a diameter substantially the same as or slightly larger than that of the enlarged diameter portion 12 of the protrusion 10. The branch piece 22 is formed with a gourd-shaped second mounting hole 24 in which the large-diameter portion 25 and the small-diameter portion 26 are integrated, with the small-diameter portion 26 side facing the first mounting hole 23 side. Has been. The large diameter portion 25 of the second mounting hole 24 is formed to have a diameter substantially the same as or slightly larger than the diameter enlarged portion 12 of the protrusion 10, and the small diameter portion 26 is slightly larger than the trunk portion 11. The diameter is smaller than 12.

  According to such a configuration, as shown in FIG. 1B, first, the projection 10 is passed through the first mounting hole 23 of the FPC 20, and then, as shown in FIG. Is folded back in the direction indicated by the arrow in the drawing, the projection 10 is passed through the large diameter portion 25 of the second mounting hole 24, and the branch piece 22 is further slid in parallel with the FPC main body 21 as indicated by the arrow in the drawing. As shown in FIG. 4D, by inserting the trunk portion 11 of the projection 10 into the small diameter portion 26 of the second mounting hole 24, the first mounting hole 23 is prevented from coming off from the projection 10.

  As described above, according to the FPC mounting structure according to the present embodiment, a stable fixing state can be realized by a simple mounting operation without requiring any special parts or tools. Moreover, in this embodiment, since the tip of the enlarged diameter portion 12 of the protrusion 10 has a sharp mushroom shape, it is possible to make it difficult to pull out while improving insertability.

  FIG. 2 is a perspective view of a main part showing an FPC mounting structure according to the second embodiment of the present invention.

  In this embodiment, as shown in FIG. 5 (a), two protrusions 10a, 10b are provided on the fixed portion, and the FPC main body 21 and the branch piece 22 of the FPC 20 are provided with first mounting holes 23a, 23b and second mounting holes 24a and 24b are formed. According to this embodiment, as shown in FIG. 5B, the two protrusions 10a and 10b are fitted to the two first mounting holes 23a and 23b and the second mounting holes 24a and 24b. Therefore, the FPC can be fixed more stably than in the previous embodiment.

  FIG. 3 is a perspective view of the main part showing the FPC mounting structure according to the third embodiment of the present invention.

  In this embodiment, as shown in FIG. 5A, the branch piece 22 is formed with an auxiliary branch piece 27 that further branches in a direction orthogonal to the branch direction. The auxiliary branch piece 27 has a gourd-shaped third mounting hole in which a large-diameter portion 29 and a small-diameter portion 30 having the same shape as the second mounting hole are integrated in a direction orthogonal to the second mounting hole 24. 28 is formed.

  In this embodiment, as shown in FIG. 5B, the auxiliary branching piece 27 is further folded back with the branching piece 22 attached to the projection 10 and passed through the large-diameter portion 29 of the third mounting hole 28. The FPC 20 is fixed in a state in which the trunk portion of the projection 10 penetrated through is fitted in the small diameter portion 30 of the third mounting hole 28.

  According to this embodiment, the movement of the FPC 20 in the two directions of the direction in which the FPC main body 21 extends and the direction orthogonal thereto is restricted, and the FPC can be fixed more stably than in the previous embodiment.

  FIG. 4 is a perspective view of an essential part showing an FPC mounting structure according to a fourth embodiment of the present invention.

  In this embodiment, a reinforcing annular land 41 made of copper foil, a copper plate or the like is formed at the edge of the first mounting hole 23, and the edge of the second mounting hole 24 is made of copper foil, a copper plate or the like. A reinforcing gourd-shaped land 42 is formed.

  With this structure, the peripheral portions of the mounting holes 23 and 24 can be reinforced and further stable fixing can be performed.

  FIG. 5 is a perspective view of an essential part showing an FPC mounting structure according to a fifth embodiment of the present invention.

  In this embodiment, as shown in FIG. 5A, a fold 51 is provided at the tip of the branch piece 22, and the tip of the branch piece 22 is bent along the fold 51, as shown in FIG. Then, the bent tip is folded into the lower surface side of the FPC main body 21.

  By doing so, it is possible to prevent the branch piece 22 from being displaced, and thus it is possible to make it difficult for the FPC 20 to come out of the protrusion 10.

  FIG. 6 is a perspective view of an essential part showing an FPC mounting structure according to a sixth embodiment of the present invention.

  In this embodiment, as shown in FIG. 6A, a fold 61 is provided at the base end of the branch piece 22, and the base end of the branch piece 22 is bent along the fold 61, as shown in FIG. Make a crease in the folded part.

  Also by doing in this way, it is possible to prevent the branch piece 22 from shifting as in the previous embodiment, so that the FPC 20 can be made difficult to come off from the protrusion 10.

It is a perspective view of the principal part for demonstrating the attachment structure and attachment method of the flexible flat circuit which concern on the 1st Embodiment of this invention. It is a perspective view of the principal part for demonstrating the attachment structure and attachment method of the flexible flat circuit which concerns on the 2nd Embodiment of this invention. It is a perspective view of the principal part for demonstrating the attachment structure and attachment method of the flexible flat circuit which concerns on the 3rd Embodiment of this invention. It is a perspective view of the principal part for demonstrating the attachment structure and attachment method of the flexible flat circuit which concerns on the 4th Embodiment of this invention. It is a perspective view of the principal part for demonstrating the attachment structure and attachment method of the flexible flat circuit which concerns on the 5th Embodiment of this invention. It is a perspective view of the principal part for demonstrating the attachment structure and attachment method of the flexible flat circuit which concerns on the 6th Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10, 10a, 10b ... Projection, 11 ... Trunk part, 12 ... Diameter expansion part, 20 ... FPC, 21 ... FPC main body, 22 ... Branch piece, 23, 23a, 23b ... 1st attachment hole, 24, 24a, 24b ... 2nd attachment hole, 25, 29 ... large diameter part, 26, 30 ... small diameter part, 27 ... auxiliary branch piece, 28 ... 3rd attachment hole, 41, 42 ... land, 51, 61 ... crease.

Claims (8)

A flexible flat circuit mounting structure for fixing the flexible flat circuit to the fixing portion by attaching a flexible flat circuit to a protrusion protruding on the fixed side,
The protrusion projecting on the fixed side has a trunk portion and an enlarged diameter portion having a larger diameter than the trunk portion formed at the tip of the trunk portion,
The flexible flat circuit is:
A flexible flat circuit body in which a first mounting hole having a diameter substantially equal to or slightly larger than that of the enlarged diameter portion of the protrusion is formed;
Branched from the flexible flat circuit main body, is substantially the same diameter as the enlarged diameter part or slightly larger than the large diameter part and the enlarged diameter part, and is substantially the same diameter or slightly larger diameter than the trunk part. And a branch piece formed with a gourd-shaped second mounting hole integrated with a small diameter portion of
The projection is penetrated through the first mounting hole of the flexible flat circuit body, the branch piece is folded back and the trunk of the projection penetrated through the large diameter part of the second mounting hole is the first mounting hole. The mounting structure of the flexible flat circuit, wherein the protrusion is prevented from coming off from the flexible flat circuit in a state of being fitted into the small diameter portion of the mounting hole.   The flexible flat circuit main body and the branch piece are each formed with two each of the first attachment hole and the second attachment hole in a direction perpendicular to the branch direction of the branch piece. The flexible flat circuit mounting structure according to claim 1, wherein: The branch piece is formed with an auxiliary branch piece that further branches in a direction orthogonal to the branch direction,
The auxiliary branch piece includes a large-diameter portion that is substantially the same diameter or slightly larger in diameter than the enlarged-diameter portion, and a small-diameter portion that is smaller in diameter than the enlarged-diameter portion and approximately the same diameter or slightly larger in diameter than the trunk portion. Are formed in a direction perpendicular to the second mounting hole, a gourd-shaped third mounting hole is formed,
In a state where the branch piece is attached to the protrusion, the auxiliary branch piece is folded and the trunk portion of the protrusion penetrated through the large diameter portion of the third attachment hole has a small diameter of the third attachment hole. The flexible flat circuit mounting structure according to claim 1, wherein the flexible flat circuit mounting structure is fitted to the portion.   The flexible flat circuit mounting according to any one of claims 1 to 3, wherein peripheral edges of the first mounting hole and the second mounting hole are reinforced by a metal land. Construction.   5. A fold is formed at the tip of the branch piece, and the tip that is bent along the fold is folded under the flexible flat circuit. The flexible flat circuit mounting structure according to claim 1.   The flexible flat circuit mounting structure according to any one of claims 1 to 4, wherein a fold is formed in the folded portion of the branch piece.   The flexible flat circuit mounting structure according to claim 1, wherein the protrusion has a mushroom shape as a whole with a sharpened tip of the enlarged diameter portion. A mounting method for a flexible flat circuit in which the flexible flat circuit is fixed to the fixing portion by attaching the flexible flat circuit to a protrusion protruding on the fixed side,
The protrusion projecting on the fixed side is configured to include a trunk part and an enlarged diameter part larger in diameter than the trunk part formed at the tip of the trunk part, and the flexible flat circuit is configured to expand the projection. A flexible flat circuit body having a first mounting hole having a diameter that is substantially the same as or slightly larger than the diameter part, and is branched from the flexible flat circuit body to be substantially the same diameter as the enlarged diameter part? Alternatively, a gourd-shaped second mounting hole is formed in which a large diameter portion having a slightly larger diameter and a smaller diameter than the enlarged diameter portion and the same diameter as the trunk portion or a slightly larger diameter small diameter portion are integrated. Formed with a branch piece,
After the projection is passed through the first mounting hole of the flexible flat circuit body, the branch piece is folded back to pass the projection through the large diameter portion of the second mounting hole, and the branch piece is The stem of the projection is inserted into the small diameter portion of the second mounting hole by sliding in parallel with the flexible flat circuit main body, thereby preventing the first mounting hole from coming off from the projection. A mounting method for a flexible flat circuit, characterized in that:

Images