Flexible printed wiring board with crimp terminal and method for manufacturing same

Abstract

To provide a flexible printed wiring board having a crimp terminal that enables stable electrical connection while maintaining the strength.SOLUTION: A printed wiring board includes an FPC 100 including a base film 110 and a circuit 120 made of metal foil provided on the surface of the base film 110, and a crimp terminal 200 having a plurality of crimping pieces 221 and 222 that are crimped to pass through the FPC 100 and bite into a part of the circuit 120 by bending, and an insulating reinforcing film 150 is partially integrally provided in a region of the base film 110 through which the plurality of crimping pieces 221 and 222 pass.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a flexible printed wiring board having a crimp terminal and a method for manufacturing the same. [Background technology]

[0002] Automobiles and other vehicles are equipped with numerous electrical components, requiring numerous electrical wiring. Conventionally used wire harnesses are heavy and bulky, so flexible printed circuit boards (FPCs) have been widely used in recent years. In particular, the demand for electric vehicles, hybrid vehicles, and fuel cell vehicles is increasing as an environmental measure, and the demand for FPCs is further increasing. In addition, there is a demand for FPCs to be made lighter, more compact, and more flexible, as well as to be multifunctional by mounting sensor components, etc.

[0003] For this reason, connectors and connection terminals for electrically connecting FPCs to various electrical components (sensing modules, ECUs, batteries, etc.) tend to be smaller. In addition, the wiring on FPCs also tends to be thinner, and the gaps between the wiring tend to be narrower. For connection terminals, crimp terminals that are easy to attach to FPCs are widely used. Crimp terminals can be attached to FPCs simply by tightening the crimp piece. However, crimp terminals used for FPCs are configured so that the crimp piece penetrates the base film and wiring in the FPC and is bent to establish electrical continuity with the wiring. For this reason, when connection terminals are made smaller and wiring is made thinner, it becomes difficult to maintain electrical continuity and the strength of each component.

[0004] In order to ensure electrical continuity, measures have been taken such as increasing the number of crimping pieces or increasing the amount of pressing of the crimping pieces to increase the contact area between the crimping pieces and the wiring, but in this case, the mechanical strength of each member is likely to decrease. Also, the mechanical strength can be increased by increasing the thickness of the base film and the cover film, but in this case, the weight increases and the flexibility decreases. Therefore, there is still room for improvement. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 4889027 [Patent Document 2] Patent No. 5465579 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide a flexible printed wiring board having crimp terminals that maintain strength and enable stable electrical connection, and a method for manufacturing the same. [Means for solving the problem]

[0007] The present invention employs the following means to solve the above problems.

[0008] That is, the flexible printed wiring board having the crimp terminal of the present invention has the following features: A flexible printed wiring board having a base film and a circuit formed of a metal foil provided on a surface of the base film; By being compressed, In the area where the circuit is not provided a crimp terminal having a plurality of crimp pieces that penetrate the flexible printed wiring board and are bent to bite into a part of the circuit; A flexible printed wiring board having a crimp terminal, The base film is characterized in that an insulating reinforcing film is partially and integrally provided in an area through which the plurality of pressure bonding pieces penetrate.

[0009] According to the present invention, since the insulating reinforcing film is integrally provided on the base film, even when the crimp terminal is attached, the strength of the flexible printed wiring board and the crimp terminal can be increased in the vicinity of the crimp piece. Moreover, since the insulating reinforcing film is provided partially, an increase in the weight of the flexible printed wiring board can be suppressed, and the flexibility of the flexible printed wiring board is not reduced.

[0010] The flexible printed wiring board may preferably have a base film that is a single-sided copper-clad laminate made of polyimide, polyethylene naphthalate, or polyethylene terephthalate.

[0011] The flexible printed wiring board has a cover film attached to the base film so as to sandwich the circuit therebetween, In some areas of the flexible printed wiring board, the cover film is not provided and part of the circuit is exposed, and at least some of the multiple pressure-bonding pieces are arranged in the some areas so that they penetrate into part of the circuit without penetrating the cover film.

[0012] This makes it possible to increase the contact area between the crimp terminal and the circuit.

[0013] The method for producing a flexible printed wiring board having a crimp terminal of the present invention includes the steps of: A step of bonding an insulating reinforcing film to a predetermined region of a base film provided on a flexible printed wiring board; a step of attaching the crimp terminal to the flexible printed wiring board by crimping a plurality of crimp pieces provided on the crimp terminal to the region where the insulating reinforcement film is provided; The present invention is characterized by comprising: Effect of the Invention

[0014] As described above, according to the present invention, it is possible to achieve a stable electrical connection while maintaining strength. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic diagram of a flexible printed wiring board having a crimp terminal according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic diagram of a flexible printed wiring board including a crimp terminal according to the first embodiment of the present invention. [Diagram 3] FIG. 3 is a schematic configuration diagram of the crimp terminal according to the first embodiment of the present invention. [Figure 4] FIG. 4 is a schematic diagram of a flexible printed wiring board including a crimp terminal according to a second embodiment of the present invention. [Diagram 5] FIG. 5 is a schematic diagram of a flexible printed wiring board including a crimp terminal according to a second embodiment of the present invention. [Figure 6] FIG. 6 is a schematic diagram of a flexible printed wiring board including a crimp terminal according to a third embodiment of the present invention. [Figure 7] FIG. 7 is a schematic diagram of a flexible printed wiring board including a crimp terminal according to a third embodiment of the present invention. [Figure 8] FIG. 8 is a schematic diagram of a flexible printed wiring board having a crimp terminal according to a fourth embodiment of the present invention. [Figure 9] FIG. 9 is a schematic diagram of a flexible printed wiring board including a crimp terminal according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, the embodiment of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative positions, and the like of the components described in the embodiment are not intended to limit the scope of the present invention unless otherwise specified.

[0017] Example 1 A flexible printed wiring board having a crimp terminal according to a first embodiment of the present invention will be described with reference to Figs. 1 to 3. Fig. 1 is a schematic diagram of a flexible printed wiring board having a crimp terminal according to a first embodiment of the present invention, in which Fig. 1(a) shows a part of a plan view of the flexible printed wiring board having the crimp terminal, and Fig. 1(b) shows a part of a side view of the flexible printed wiring board having the crimp terminal. Fig. 2 is a schematic diagram of a flexible printed wiring board having a crimp terminal according to a first embodiment of the present invention, in which Fig. 2(a) shows a part of a rear view of the flexible printed wiring board having the crimp terminal, and Fig. 2(b) is a schematic cross-sectional view of the flexible printed wiring board having the crimp terminal, which is a cross-sectional view taken along line AA in Fig. 1(a) (the box part of the crimp terminal is omitted). Fig. 3 is a schematic diagram of a crimp terminal according to a first embodiment of the present invention, in which Fig. 3(a) shows a state in which the crimp terminal is viewed from the rear end, and Fig. 3(b) shows a side view of the crimp terminal. It should be noted that FIG. 3 shows the crimp terminal in a state before it is crimped, and FIGS. 1 and 2 show the state after it has been crimped.

[0018] <Flexible printed circuit board with crimp terminals> The configuration of a flexible printed wiring board with crimp terminals according to this embodiment (hereinafter, appropriately referred to as "FPC10 with terminals") will be described. The FPC10 with terminals includes a flexible printed wiring board (hereinafter, referred to as "FPC100") and a crimp terminal 200 attached to the FPC100.

[0019] The FPC 100 has a base film 110, a circuit 120 made of a metal foil (such as copper foil) provided on the surface of the base film 110, and a cover film 130 attached to the base film 110 so as to sandwich the circuit 120. An adhesive layer 140 is formed between the base film 110 and the cover film 130 to attach them together.

[0020] In the FPC 100 according to this embodiment, an insulating reinforcing film 150 is integrally provided in a predetermined region of the base film 110. The base film 110 is made of polyimide, polyethylene naphthalate, or polyethylene terephthalate. In the FPC 100 configured as above, when the circuit 120 is made of copper foil, it is called a single-sided copper-clad laminate.

[0021] The crimp terminals 200 are attached to the FPC 100 by a crimping jig or crimping device (not shown). In this embodiment, an example is shown in which four crimp terminals 200 are attached to the FPC 100. However, it goes without saying that the number of crimp terminals 200 attached to the FPC 100 varies depending on the product.

[0022] The crimp terminal 200 according to this embodiment is a female terminal, and includes a box portion 210 into which the terminal tip of a male terminal is inserted, and a tongue portion 211 for elastically clamping the terminal tip of the male terminal. The crimp terminal 200 according to this embodiment includes a plurality of crimping pieces 221, 222. The plurality of crimping pieces 221, 222 are arranged alternately on both sides in the width direction (direction perpendicular to the direction from the terminal tip to the rear end). Note that, although a configuration in which four crimping pieces 221, 222 are provided is shown, the crimping The numbers of pieces 221 and 222 can be set appropriately.

[0023] The crimping pieces 221, 222 are configured to penetrate the FPC 100 by being crimped, and are bent to bite into a part of the circuit 120. In this embodiment, the crimp terminal 200 is attached to the FPC 100 such that the crimping pieces 221, 222 pierce from the insulating reinforcement film 150 side of the FPC 100 toward the cover film 130 side. Note that in the present invention, various known crimp terminals may be adopted as long as they are provided with the crimping pieces 221, 222 as described above. Also, in this embodiment, the crimp terminal is shown as a female terminal, but the crimp terminal in the present invention may also be applied to a male terminal provided with similar crimping pieces.

[0024] <Manufacturing method for FPC with crimp terminals> A method for manufacturing an FPC 100 including a crimp terminal 200 will be described in the order of manufacturing steps. First, a part of a metal foil such as a copper foil provided on the surface of a base film 110 is removed by etching to form a circuit 120. Next, an adhesive is applied, and then a cover film 130 is provided. After that, an insulating reinforcement film 150 is attached to a predetermined region of the base film 110. Then, the crimp terminal 200 is attached to the region where the insulating reinforcement film 150 is provided by crimping a plurality of crimp pieces 221, 222 provided on the crimp terminal 200. In the terminal-equipped FPC 10 manufactured as described above, it can be said that the insulating reinforcement film 150 is partially and integrally provided in the region of the base film 110 through which the plurality of crimp pieces 221, 222 penetrate.

[0025] <Advantages of the flexible printed wiring board having the crimp terminal according to the present embodiment> According to the terminal-attached FPC 10 of this embodiment, the insulating reinforcing film 150 is integrally provided on the base film 110. This can increase the rigidity of the portion where the insulating reinforcing film 150 is provided. Since the crimp terminal 200 is attached to the portion where the insulating reinforcing film 150 is provided, the strength of the FPC 100 and the crimp terminal 200 can be increased in the vicinity of the crimp pieces 221, 222, and deformation of these can be suppressed. This allows for stable electrical connection. Furthermore, since the insulating reinforcing film 150 is provided partially, it is possible to suppress an increase in the weight of the FPC 100, and the flexibility of the FPC 100 is not reduced. According to the terminal-attached FPC 10 of this embodiment, the structure of the crimp terminal 200 does not need to be complicated as in the techniques disclosed in Patent Documents 1 and 2, so there are many types of connectors that can be applied, it is versatile, and there is no increase in cost.

[0026] Example 2 4 and 5 show a second embodiment of the present invention. In the first embodiment, a configuration was shown in which a crimp terminal is attached to an FPC such that a crimp piece pierces from the insulating reinforcing film side of the FPC toward the cover film side. In contrast, in the present embodiment, a configuration was shown in which a crimp terminal is attached to an FPC such that a crimp piece pierces from the cover film side of the FPC toward the insulating reinforcing film side. The configuration of the FPC itself and the configuration of the crimp terminal itself are the same as those in the first embodiment, so the same components are denoted by the same reference numerals and their description will be omitted as appropriate.

[0027] Fig. 4 is a schematic diagram of a flexible printed wiring board with crimp terminals according to a second embodiment of the present invention, where (a) shows a part of a rear view of the flexible printed wiring board with crimp terminals, and (b) shows a part of a side view of the flexible printed wiring board with crimp terminals. Fig. 5 is a schematic diagram of a flexible printed wiring board with crimp terminals according to a first embodiment of the present invention, where (a) shows a part of a plan view of the flexible printed wiring board with crimp terminals, and (b) shows a part of a side view of the flexible printed wiring board with crimp terminals. 5(a) (the box portion of the crimp terminal is omitted). FIG.

[0028] The configuration of a flexible printed wiring board with crimp terminals according to this embodiment (hereinafter, appropriately referred to as "FPC with terminals 10X") will be described. The FPC with terminals 10X includes a flexible printed wiring board (hereinafter, referred to as "FPC100") and a crimp terminal 200 attached to the FPC 100. The configuration of the FPC 100 itself and the configuration of the crimp terminal 200 itself are as described in the first embodiment above.

[0029] In this embodiment, the crimp terminal 200 is attached to the FPC 100 such that the crimping pieces 221, 222 pierce from the cover film 130 side of the FPC 100 toward the insulating reinforcement film 150 side. The manufacturing method of the terminal-equipped FPC 10X according to this embodiment is also the same as that of the first embodiment.

[0030] The terminal-equipped FPC 10X according to this embodiment configured as above can also provide the same effects as those of the first embodiment.

[0031] Example 3 6 and 7 show Example 3 of the present invention. In the above Examples 1 and 2, a cover film is provided over the entire surface of the circuit opposite the base film. In contrast, this Example shows a configuration in which no cover film is provided in the area where the crimp terminals are provided. The other basic configuration is the same as in Example 1, so the same components are denoted by the same reference numerals and their explanation will be omitted as appropriate.

[0032] Fig. 6 is a schematic diagram of a flexible printed wiring board having a crimp terminal according to a third embodiment of the present invention, where (a) shows a part of a plan view of the flexible printed wiring board having the crimp terminal, and (b) shows a part of a side view of the flexible printed wiring board having the crimp terminal. Fig. 7 is a schematic diagram of a flexible printed wiring board having a crimp terminal according to a third embodiment of the present invention, where (a) shows a part of a rear view of the flexible printed wiring board having the crimp terminal, and (b) is a schematic cross-sectional view of the flexible printed wiring board having the crimp terminal, which is a CC cross-sectional view in Fig. 6(a) (the box part of the crimp terminal is omitted).

[0033] The configuration of a flexible printed wiring board with crimp terminals according to this embodiment (hereinafter, appropriately referred to as "FPC 10Y with terminals") will be described. The FPC 10Y with terminals includes a flexible printed wiring board (hereinafter, referred to as "FPC 100") and a crimp terminal 200 attached to the FPC 100. The configuration of the crimp terminal 200 is as described in the first embodiment above.

[0034] The FPC 100 has a base film 110, a circuit 120 made of a metal foil (such as copper foil) provided on the surface of the base film 110, and a cover film 130 attached to the base film 110 so as to sandwich the circuit 120. An adhesive layer 140 is formed between the base film 110 and the cover film 130 to attach them together.

[0035] In the FPC 100 according to this embodiment, an insulating reinforcing film 150 is integrally provided in a predetermined region of the base film 110. The base film 110 is made of polyimide, polyethylene naphthalate, or polyethylene terephthalate. In the FPC 100 configured as described above, when the circuit 120 is made of copper foil, it is called a single-sided copper-clad laminate. In addition, in a portion of the region of the FPC 100 according to this embodiment, In this area, the cover film 130 is not provided and a part of the circuit 120 is exposed.

[0036] The crimping pieces 221, 222 of the crimp terminal 200 are configured to penetrate the FPC 100 when crimped, and are bent to bite into a part of the circuit 120. In this embodiment, the cover film 130 is not provided in the area where the crimping pieces 221, 222 are crimped. In this embodiment, the crimping terminal 200 is attached to the FPC 100 such that the crimping pieces 221, 222 pierce from the insulating reinforcement film 150 side of the FPC 100 toward the base film 110 side.

[0037] In the present invention, various known crimp terminals can be used as long as they have the above-mentioned crimp pieces 221, 222. In this embodiment, the crimp terminal is a female terminal, but the crimp terminal in the present invention can also be applied to a male terminal having similar crimp pieces. The manufacturing method of the terminal-equipped FPC 10Y according to this embodiment is the same as that of the above-mentioned embodiment 1.

[0038] The terminal-equipped FPC 10Y according to the present embodiment configured as described above can also provide the same effects as those of the first embodiment. Moreover, according to the terminal-equipped FPC 10Y according to the present embodiment, all the crimping pieces 221, 222 are configured to bite into a part of the exposed circuit 120 without penetrating the cover film 130, so that the contact area between these crimping pieces 221, 222 and the circuit 120 can be made large. That is, when the crimping pieces 221, 222 bite into a part of the circuit 120 while penetrating the cover film 130, a part of the cover film 130 is likely to get into the vicinity of the connection part between the crimping pieces 221, 222 and the circuit 120, and the contact area between the crimping pieces 221, 222 and the circuit 120 is likely to be narrowed. In contrast, by adopting a configuration in which the crimping pieces 221, 222 bite into a part of the exposed circuit 120, the contact area between the crimping pieces 221, 222 and the circuit 120 can be made large. Therefore, the electrical connection can be made more stable. Furthermore, the strength of the pressure-bonded portion is also ensured because the base film 110 and the insulating reinforcing film 150 are provided, so that a stable electrical connection can be achieved while maintaining strength.

[0039] In this embodiment, all the pressure-bonding pieces 221, 222 are configured to bite into a part of the exposed circuit 120 without penetrating the cover film 130. However, for some of the pressure-bonding pieces 221, 222, an area where the cover film 130 is not provided may be set so that the pressure-bonding pieces penetrate the cover film 130. That is, in consideration of the balance between the strength and the stability of the electrical connection, the allocation of the pressure-bonding pieces arranged in the area where the circuit 120 is exposed and the pressure-bonding pieces arranged in the area where the cover film 130 is provided may be set according to the usage environment, etc.

[0040] Example 4 8 and 9 show Example 4 of the present invention. In Example 3 above, a configuration was shown in which a crimp terminal is attached to an FPC such that a crimp piece pierces from the insulating reinforcing film side of the FPC toward the base film side. In contrast, in this example, a configuration is shown in which a crimp terminal is attached to an FPC such that a crimp piece pierces from the base film side of the FPC toward the insulating reinforcing film side. The configuration of the FPC itself is the same as in Example 3, and the configuration of the crimp terminal itself is the same as in Example 1, so the same components are denoted by the same reference numerals and their description will be omitted as appropriate.

[0041] Fig. 8 is a schematic diagram of a flexible printed wiring board having a crimp terminal according to a fourth embodiment of the present invention, in which (a) shows a part of a rear view of the flexible printed wiring board having the crimp terminal, and (b) shows a part of a side view of the flexible printed wiring board having the crimp terminal. 8(a) is a schematic diagram of a wiring board, in which FIG. 8(a) shows a portion of a plan view of a flexible printed wiring board equipped with a crimp terminal, and FIG. 8(b) is a schematic cross-sectional view of a flexible printed wiring board equipped with a crimp terminal, which is a DD cross-sectional view in FIG. 8(a) (the box portion of the crimp terminal is omitted).

[0042] The configuration of a flexible printed wiring board with crimp terminals according to this embodiment (hereinafter, appropriately referred to as "FPC with terminals 10Z") will be described. The FPC with terminals 10Z includes a flexible printed wiring board (hereinafter, referred to as "FPC100") and a crimp terminal 200 attached to the FPC 100. The configuration of the FPC 100 itself is as described in the third embodiment, and the configuration of the crimp terminal 200 itself is as described in the first embodiment.

[0043] In this embodiment, the crimp terminal 200 is attached to the FPC 100 such that the crimping pieces 221, 222 pierce from the base film 110 side of the FPC 100 toward the insulating reinforcement film 150 side. The manufacturing method of the terminal-equipped FPC 10Z according to this embodiment is also the same as that of the first embodiment.

[0044] The terminal-equipped FPC 10Z according to this embodiment configured as above can also provide the same effects as those of the above-mentioned Example 3. Note that, as with the above-mentioned Example 3, some of the crimping pieces 221, 222 may have regions in which the cover film 130 is not provided so as to penetrate the cover film 130. [Explanation of symbols]

[0045] 10,10X,10Y,10Z Terminaled FPC 110 Base Film 120 circuits 130 Cover Film 140 Adhesive layer 150 Insulating reinforcement film 200 Crimp terminal 210 Box Section 211 Tongue piece 221,222 Crimping piece

Claims

1. A flexible printed wiring board having a base film and a circuit formed of a metal foil provided on a surface of the base film; a crimp terminal including a plurality of crimp pieces that are crimped to penetrate the flexible printed wiring board in an area where the circuit is not provided and are bent to bite into a part of the circuit; A flexible printed wiring board having a crimp terminal, A flexible printed wiring board having a crimp terminal, characterized in that an insulating reinforcing film is partially and integrally provided in an area of ​​the base film through which the multiple crimping pieces pass.

2. 2. The flexible printed wiring board having a crimp terminal according to claim 1, characterized in that the base film of the flexible printed wiring board is a single-sided copper-clad laminate made of polyimide, polyethylene naphthalate, or polyethylene terephthalate.

3. The flexible printed wiring board has a cover film attached to the base film so as to sandwich the circuit therebetween, A flexible printed wiring board having a crimp terminal as described in claim 1 or 2, characterized in that in a portion of the flexible printed wiring board, the cover film is not provided and a portion of the circuit is exposed, and at least a portion of the multiple crimp pieces are arranged in the portion of the board so as to penetrate the cover film and thereby to embed themselves in a portion of the circuit.

4. A step of bonding an insulating reinforcing film to a predetermined region of a base film provided on a flexible printed wiring board; a step of attaching the crimp terminal to the flexible printed wiring board by crimping a plurality of crimp pieces provided on the crimp terminal to the region where the insulating reinforcement film is provided; A method for manufacturing a flexible printed wiring board having a crimp terminal, comprising:

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