JP2008147379A - Connection structure and connection method of flexible wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connection structure and a connection method of a flexible wiring board which copes with compaction of an electronic apparatus while exhibiting good flexibility. <P>SOLUTION: The connection structure 100 of a flexible printed wiring board comprises first and second flexible printed wiring boards 110 and 120, a connection member 130, and a reinforcing plate 140. The second flexible printed wiring board 120 is arranged oppositely to the first flexible printed wiring board 110. The connection member 130 connects the first and second flexible printed wiring boards 110 and 120. The reinforcing plate 140 has a rigidity higher than that of the first and second flexible printed wiring boards 110 and 120, and it is connected to a portion opposite the connection member 130 through the first flexible printed wiring board 110 on the side of the first flexible printed wiring board 110 opposite to the side where the connection member 130 is arranged. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a flexible wiring board connection structure and a flexible wiring board connection method, and more particularly to a flexible wiring board connection structure and a flexible wiring board connection method having high flexibility.

  In recent years, along with the improvement in performance of electronic devices such as HDDs (hard disk drives), flexible wiring boards such as flexible printed wiring boards are widely used for applications such as wiring to movable parts of electronic devices. In such an electronic device, a flexible wiring board having a desired shape is used by connecting a plurality of flexible wiring boards.

  As a connection structure of a plurality of flexible printed wiring boards, for example, JP 2003-101167 A (Patent Document 1) discloses a connection structure using a connector. Specifically, a flexible printed wiring board is disclosed in which a connector connection portion is formed at an end portion, and a connection terminal is formed on a conductor circuit layer whose surface is exposed in the connector connection portion. And the some flexible printed wiring board is connected by inserting the said connection terminal in the connector insertion port formed in the connector.

As another connection structure for a plurality of flexible printed wiring boards, JP 2000-58996 A (Patent Document 2) uses a anisotropic conductive adhesive to connect a plurality of flexible printed wiring boards. Is disclosed. Specifically, the metal bumps provided on the first flexible printed wiring board and the connection pads provided on the second flexible printed wiring are electrically connected via an anisotropic conductive adhesive. By doing so, the 1st and 2nd flexible printed wiring boards are connected.
JP 2003-101167 A JP 2000-58996 A

  However, in the connection using the connector described in Patent Document 1, it is necessary to provide a connector having a thickness of about several millimeters in order to connect the flexible printed wiring board. .

  Moreover, in the connection by the bump described in Patent Document 2, the thickness of the connection portion of the first and second flexible printed wiring boards is increased depending on the thickness of the bump, so that the flexibility of the connected flexible printed wiring board is increased. In addition to the decrease, there is a problem that it is not possible to cope with downsizing of electronic devices.

  Furthermore, in the connection structure for a plurality of flexible printed wiring boards disclosed in Patent Documents 1 and 2, if a highly flexible flexible printed wiring board is used, the flexible printed wiring board may be broken. Therefore, there exists a problem that a highly flexible flexible printed wiring board cannot be used.

  Accordingly, an object of the present invention is to provide a flexible wiring board connection structure and a flexible wiring board connection method that can cope with downsizing of electronic devices and have good flexibility.

  The connection structure of the flexible wiring board of this invention is equipped with the 1st flexible wiring board, the 2nd flexible wiring board, the connection member, and the reinforcement board. The second flexible wiring board is disposed so as to face the first flexible wiring board. The connecting member electrically connects the first flexible wiring board and the second flexible wiring board. The reinforcing plate has a higher rigidity than the first and second flexible wiring boards, and is a surface on the opposite side to the surface on which the connection member is arranged in the first flexible wiring board, and the first flexible wiring board It connects with all or one part of the part which opposes a connection member via.

  According to the flexible wiring board connection structure of the present invention, since the reinforcing plate is provided to reinforce at least the connection portion of the first and second flexible wiring boards, at least one of the first and second flexible wiring boards is provided. Even when the flexibility is good, it is possible to prevent the first and second flexible wiring boards from being broken at the time of bending. Therefore, the flexibility is improved. In addition, since the first and second flexible wiring boards are connected using the connecting member at a position facing each other, the size can be reduced.

  In the connection structure of the flexible wiring board, the connection member is preferably a thermosetting resin.

  Thereby, the connection of a 1st and 2nd flexible wiring board can be ensured. Moreover, even if the patterns of the first and second flexible wiring boards have a narrow pitch, a short circuit can be prevented.

  In the connection structure of the flexible wiring board, preferably, the connection member is an anisotropic conductive film (ACF: Anisotropic Conductive Film).

  Thereby, even if it is a case where the pitch of the pattern of a 1st and 2nd flexible wiring board is small, a 1st and 2nd flexible wiring board can be connected more reliably. In addition, even when the patterns of the first and second flexible wiring boards are narrow pitches, a short circuit can be further prevented.

  The above-mentioned “anisotropic conductive film” is a property in which fine conductive particles are dispersed in a film-like insulating resin material and the conductivity in a specific (inter-surface) direction is high (anisotropic conductivity). Means a film with

  Preferably, in the connection structure of the flexible wiring board, the reinforcing plate is also opposed to a portion of the second flexible wiring board where the connecting member is not disposed, and connects the reinforcing plate and the portion of the second flexible wiring board. An adhesive is further provided.

  Thereby, a 2nd flexible wiring board and a reinforcement board can be connected. Therefore, the flexibility of the second flexible wiring board can be utilized. In addition, the strength of the second flexible wiring board other than the joint with the first flexible wiring board can be improved.

  In the flexible wiring board connection structure, the adhesive is preferably a thermosetting resin. Thereby, a 2nd flexible wiring board and a reinforcement board can be connected more reliably.

  In the flexible wiring board connection structure, the reinforcing plate is preferably made of at least one substance selected from the group consisting of polyimide, glass epoxy, paper phenol, copper, copper alloy, aluminum, and aluminum alloy.

  Thereby, since the rigidity of a reinforcement board improves, the flexibility of the 1st and 2nd flexible wiring board can be utilized more.

  In the flexible wiring board connection structure, the second flexible wiring board preferably has high flexibility.

  Thereby, even if the second flexible wiring board has high flexibility, it is possible to prevent the second flexible wiring board from being broken by the reinforcing plate. Further, since the second flexible wiring board has high flexibility, a wider connection structure can be obtained.

The “high flexibility” means a bending radius R of 2.5 mm, a speed of 1500 times / minute, a stroke of 20 mm, and a temperature of a sliding bending test measured according to JIS C-5016. under conditions of 80 ° C., which means that the flex life N _f is ^{105 to 106.}

  The connection method of the flexible wiring board of this invention is equipped with the preparation process, the 1st connection process, and the 2nd connection process. The preparation step prepares a first flexible wiring board, a second flexible wiring board, and a reinforcing plate having higher rigidity than the first and second flexible wiring boards. In the first connecting step, the first flexible wiring board is connected to the second flexible wiring board disposed so as to face the first flexible wiring board with a connecting member. In the second connection step, the reinforcing plate is connected to all or a part of the surface of the first flexible wiring board opposite to the surface connected to the second flexible wiring board.

  According to the connecting method of the flexible wiring board of the present invention, the first and second flexible wiring boards, the connecting member connecting the first and second flexible wiring boards, and the first flexible wiring board are connected. A connection structure of a flexible wiring board provided with a reinforcing plate can be obtained. For this reason, the first and second flexible wiring boards are provided with a reinforcing plate that at least reinforces the connection portions of the first and second flexible wiring boards and the portions other than the connection portions of the first flexible wiring boards. Even when at least one of them is flexible, it is possible to prevent the first and second flexible wiring boards from being broken during bending. Therefore, it is possible to obtain a connection structure of a flexible wiring board with good flexibility. In addition, since the first and second flexible wiring boards are connected using the connecting member at a position where the first and second flexible wiring boards are opposed to each other, a connection structure of the flexible wiring board that can be miniaturized can be obtained.

  Preferably, the flexible wiring board connection method further includes a third connection step of connecting the second flexible wiring board and the reinforcing plate with an adhesive.

  By performing the third connection step, the reinforcing plate and the second flexible wiring board can be connected. Therefore, the flexibility of the second flexible wiring board can be utilized. Further, the strength of the second flexible wiring board other than the connection part with the first flexible wiring board can be improved.

  In the flexible wiring board connection method, preferably, the second connection step and the third connection step are performed simultaneously. Thereby, the number of processes can be reduced.

  In the present invention, the “flexible wiring board” includes a flexible printed circuit board (FPC) and a flexible flat cable (FFC).

  According to the flexible wiring board connection structure and the flexible wiring board connection method of the present invention, since the reinforcing plate is provided, it is possible to cope with the downsizing of the electronic device and the flexibility is improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

  FIG. 1 is a schematic sectional view showing a connection structure of a flexible printed wiring board in an embodiment of the present invention. With reference to FIG. 1, the connection structure of the flexible printed wiring board (FPC) as an example of the flexible wiring board in embodiment of this invention is demonstrated. The flexible printed wiring board connection structure 100 according to the embodiment includes a first flexible printed wiring board 110, a second flexible printed wiring board 120, a connection member 130, and a reinforcing plate 140. The second flexible printed wiring board 120 is disposed so as to face the first flexible printed wiring board 110. The connection member 130 electrically connects the first flexible printed wiring board 110 and the second flexible printed wiring board 120. The reinforcing plate 140 has higher rigidity than the first and second flexible printed wiring boards 110 and 120, and the surface 110b opposite to the surface 110a on which the connecting member 130 is disposed in the first flexible printed wiring board 110. In this case, the first flexible printed wiring board 110 is connected to all or a part 110b1 of the portion facing the connection member 130.

  The flexible printed wiring board connection structure 100 in the embodiment is a connection structure of two flexible printed wiring boards. The flexible printed wiring board connection structure 100 includes first and second flexible printed wiring boards 110 and 120, a connection member 130, a reinforcing plate 140, and adhesives 150 and 160. In the flexible printed wiring board connection structure 100, the connection members 130 are arranged on the patterns 112 and 122 at the ends of the first and second flexible printed wiring boards 110 and 120, and the first and second flexible printed wiring boards 110 and 120 are connected to each other. The second flexible printed wiring boards 110 and 120 are formed so as to overlap each other. That is, the flexible printed wiring boards 110 and 120 are arranged to face each other with the connection member 130 as the center.

  Specifically, as shown in FIG. 1, the first and second flexible printed wiring boards 110 and 120 include a base film 111 and 121, and patterns 112 and 122 formed on the base film 111 and 121, respectively. , Adhesives 113 and 123 formed on the patterns 112 and 122 and cover films 114 and 124 are provided. The patterns 112 and 122 are exposed at the ends of the first and second flexible printed wiring boards 110 and 120. The first and second flexible printed wiring boards 110 and 120 are not particularly limited as long as the first and second flexible printed wiring boards 110 and 120 are provided with the base films 111 and 121 and the patterns 112 and 122, respectively. At least one of 124 may not be provided, and other configurations may be provided.

  Base films 111 and 121 are not particularly limited, and are made of polyimide, for example. The patterns 112 and 122 are not particularly limited as long as they are conductive, and are made of a metal thin film such as a copper foil. In the embodiment, the patterns 112 and 122 are formed at the ends of the flexible printed wiring boards 110 and 120. However, the patterns 112 and 122 are not particularly limited thereto, and the patterns 112 and 122 are formed on the flexible printed wiring boards 110 and 120. One or more may be formed at any location. The adhesives 113 and 123 are not particularly limited as long as the patterns 112 and 122 and the cover films 114 and 124 can be bonded, and for example, a thermosetting resin can be used. The cover films 114 and 124 are not particularly limited, and are made of polyimide, for example.

  In the embodiment, the first flexible printed wiring board 110 is a highly functional flexible printed wiring board further including a mounting component (not shown) connected to the pattern 112 by an adhesive such as solder. . The mounting parts are not particularly limited, and a desired number of arbitrary parts are arranged in a desired part.

  The second flexible printed wiring board 120 is highly flexible and is an inexpensive flexible printed wiring board.

  The first and second flexible printed wiring boards 110 and 120 may be single-sided boards having patterns 112 and 122 only on one side of the base films 111 and 121, as shown in FIG. It is not limited. For example, the first and second flexible printed wiring boards 110 and 120 may be double-sided boards having patterns on both side surfaces of the base films 111 and 121. In addition, the flexible printed wiring boards 110 and 120 may be multilayer boards in which insulators such as cover films 114 and 124 and patterns are stacked. When the first flexible printed wiring board 110 is a highly functional flexible printed wiring board on which mounting components are mounted, it is preferably a double-sided board or a multilayer board. In addition, when the second flexible printed wiring board 120 is a flexible printed wiring board that is highly flexible and inexpensive, it is preferably a single-sided board.

  In addition, a single-sided board means what has a pattern (circuit) only on one side of a wiring board. A double-sided board means what has a pattern (circuit) on both surfaces of a wiring board. A multilayer board means what laminated | stacked the insulator and the pattern (circuit) on the wafer form.

  The second flexible printed wiring board 120 preferably has high flexibility. If it has high flexibility, it is possible to prevent the pattern 122 that is a conductive wire from being cut even if the second flexible printed wiring board 120 is rounded or otherwise deformed. The first flexible printed wiring board 120 may also have high flexibility.

Note that “high flexibility” means a bending radius R of 2.5 mm, a speed of 1500 times / minute, a stroke of 20 mm, and a temperature of 80 in a sliding bending test measured in accordance with JIS C-5016. at ℃ conditions, it means that the flex life N _f is ^{105 to 106.} Here, the sliding bending test will be described with reference to FIG. FIG. 2 is a schematic diagram for explaining the sliding bending test.

In the sliding bending test, as shown in FIG. 2, first, the flexible printed wiring board 20 is fixed to the fixing plate 11 with the holding metal fitting 12 so that the flexible printed wiring board 20 is bent into a U shape with the bending radius R described above. The other end is fixed to the drive plate 13. Next, the drive plate 13 is repeatedly slid at the above speed and stroke until the flexible printed wiring board 20 is disconnected under the condition where the temperature is 80 ° C. Next, the disconnection detection device terminal 14 measures the number of bending times until breakage flexible printed wiring board 20, determine the flex life N _f from the bent number. Thus measured bending life N _f is a flexible printed circuit board 20 is ^{105 to 106} and high flexibility.

  The connection member 130 is a member for making an electrical connection between the first flexible printed wiring board 110 and the second flexible printed wiring board 120, and is preferably a thermosetting resin. For example, an epoxy resin can be used as the thermosetting resin. Moreover, as a thermosetting resin, resin with high heat resistance is preferable, and it is more preferable that heat resistance is 100 degreeC or more.

  The connecting member 130 is preferably an anisotropic conductive film. When an anisotropic conductive film is used for the connecting member 130, even if the pitch (pitch P in FIG. 3) that is the distance between the centers of the adjacent patterns 112 and 122 is narrowed, a short circuit by the connecting member 130 can be prevented.

  The reinforcing plate 140 has higher rigidity than the first and second flexible printed wiring boards 110 and 120. Since the flexible printed wiring board is a flexible printed wiring board that can be deformed greatly, the first flexible printed wiring board 110 (or the first and second flexible printed wiring boards 110, 120) can be prevented from being bent. The rigidity means a dimensional change with respect to bending or twisting force, and a small dimensional change is assumed to be high in rigidity.

  The reinforcing plate 140 is preferably a hard plate made of an engineering plastic such as polyimide, glass epoxy, and paper phenol, or a metal plate of alloy steel such as copper, copper alloy, aluminum, aluminum alloy, and stainless steel. More preferably, it is made of at least one substance selected from the group consisting of glass epoxy, paper phenol, copper, copper alloy, aluminum, and aluminum alloy. Glass epoxy is obtained by impregnating a glass cloth (cloth) with an epoxy resin. Paper phenol is paper impregnated with phenol resin.

  The reinforcing plate 140 is a surface 110b opposite to the surface 110a on which the connection member 130 is disposed in the first flexible printed wiring board 110, and faces the connection member 130 through the first flexible printed wiring board 110. All or a part 110b1 of the part and the part 120a1 of the part 120a where the connecting member 130 is not arranged in the second flexible printed wiring board 120 are opposed. All or a part 110b1 of the first flexible printed wiring board 110 and a part 120a1 of the second flexible printed wiring board 120 are mechanically connected to the reinforcing plate 140 by adhesives 150 and 160, respectively. Yes. The reinforcing plate 140 is preferably connected to all or a part of the first flexible printed wiring board 110 or a part of the part 110b1 of the first flexible printed wiring board 110 and a part 120a of the part 120 of the second flexible printed wiring board 120.

  Adhesives 150 and 160 are not particularly limited as long as first and second flexible printed wiring boards 110 and 120 and reinforcing plate 140 can be connected. The adhesives 150 and 160 are preferably thermosetting resins, and preferably contain one or more types of epoxy resins and one or more types of latent curing agents. Moreover, it is preferable that the adhesives 150 and 160 have heat resistance. The epoxy resin to be used is not particularly limited. For example, bisphenol A type, F type, S type, or AD type epoxy resin, naphthalene type epoxy resin, novolac type epoxy resin, biphenyl type epoxy resin, or A dicyclopentadiene type epoxy resin or the like can be used. Further, a high molecular weight epoxy resin having a molecular weight of 15000 or more such as a phenoxy resin and a low molecular weight epoxy resin having a molecular weight of 2000 or less can be used in appropriate combination.

  Also, the latent curing agent means a curing agent that has excellent storage stability at low temperature and hardly causes an effective reaction at room temperature, but quickly performs a curing reaction by setting it to a predetermined condition by heating or the like. To do. As this latent curing agent, imidazole series, hydrazide series, boron trifluoride-amine complex, amine imide, polyamine series, tertiary amine, alkyl urea series and other amine series, dicyandiamide series, acid and acid anhydride series curing Agents, basic active hydrogenated compounds, and modified products thereof are exemplified, and these can be used alone or as a mixture of two or more.

  In particular, these latent curing agents coated with a polymer material such as polyurethane and polyester, a metal thin film such as nickel and copper, and an inorganic material such as calcium silicate, This is preferable because it is possible to achieve both contradictory properties of storage stability and fast curability. Therefore, a microcapsule type imidazole-based latent curing agent is particularly preferable.

  Next, with reference to FIGS. 1 and 3 to 5, a method for connecting a flexible printed wiring board (FPC) as an example of the flexible wiring board in the embodiment of the present invention will be described. FIG. 3 is a schematic top view for explaining a connecting method of the flexible printed wiring board in the embodiment of the present invention. FIG. 4 is a schematic cross-sectional view for explaining the method for connecting the flexible printed wiring boards in the embodiment of the present invention. FIG. 5 is a flowchart showing a connecting method of the flexible printed wiring board in the embodiment of the present invention.

  First, as shown in FIGS. 3 to 5, the first flexible printed wiring board 110, the second flexible printed wiring board 120, and the first and second flexible printed wiring boards 110 and 120 have higher rigidity. A preparation step (S10) for preparing the reinforcing plate 140 is performed.

  In the preparation step (S10), for example, the base films 111 and 121, the patterns 112 and 122 formed on the base films 111 and 121, the adhesives 113 and 123 formed on the patterns 112 and 122, and the cover film 114 are formed. , 124 are prepared. First and second flexible printed wiring boards 110, 120 are prepared. Moreover, it is preferable that the 2nd flexible printed wiring board 120 has high flexibility.

  In the preparation step (S10), there is no particular limitation as long as it has higher rigidity than the first and second flexible printed wiring boards 110 and 120, but polyimide, glass epoxy, paper phenol, copper, copper alloy, It is preferable to prepare a reinforcing plate 140 made of at least one substance selected from the group consisting of aluminum and aluminum alloys.

  Next, as shown in FIGS. 3 and 5, the first flexible printed wiring board 110 is connected to the second flexible printed wiring board 120 arranged so as to face the first flexible printed wiring board 110. A first connection step (S20) in which the members 130 are electrically connected is performed.

  In the first connection step (S20), any method can be adopted as a method of connecting the first and second flexible printed wiring boards 110, 120 with the connection member 130. Specifically, for example, the exposed patterns of the first and second flexible printed wiring boards 110 and 120 are arranged to face each other. Then, the connection member 130 is disposed on one of the patterns 112 and 122 of the first and second flexible printed wiring boards 110 and 120. Then, the first and second flexible printed wiring boards 110 and 120 are electrically connected by the connecting member 130.

  The connection member 130 is not particularly limited, but is preferably a thermosetting resin. In this case, the first and second flexible printed wiring boards 110 and 120 are electrically connected by heating and curing the thermosetting resin to a temperature higher than the melting point.

  Further, the connecting member 130 is more preferably an anisotropic conductive film. In this case, the first and second flexible printed wiring boards 110 and 120 are connected by performing heating and pressing under conditions according to the anisotropic conductive film to be used. When the connection member 130 is an anisotropic conductive film, the connection is made in the thickness direction of the anisotropic conductive film, so the patterns 112 and 122 of the first and second flexible printed wiring boards 110 and 120 are connected. Are electrically connected.

  Next, the second connection for connecting the reinforcing plate 140 with all or a part 110b1 of the surface 110b opposite to the surface 110a connected to the second flexible printed wiring board 120 in the first flexible printed wiring board 110. Step (S30) is performed.

  Specifically, in the second connection step (S30), as shown in FIGS. 4 and 5, the surface 110b of the first flexible printed wiring board 110 is opposite to the surface 110a on which the connection member 130 is disposed. Then, all or a part 110b1 (all in the embodiment) of the part facing the connection member 130 via the first flexible printed wiring board 110 and the reinforcing plate 140 are arranged to face each other. At this time, on the surface 110b on the opposite side of the first flexible printed wiring board 110, the whole or a part of the part other than the part 110b1 and the reinforcing plate 140 are arranged to face each other. Then, the first flexible printed wiring board 110 and the reinforcing plate 140 are mechanically connected by the adhesive 150.

  The adhesive 150 is not particularly limited, but is preferably a thermosetting resin, and more preferably contains one or more types of epoxy resins and one or more types of latent curing agents.

  Next, the 3rd connection process (S40) which connects the 2nd flexible printed wiring board 120 and the reinforcement board 140 with the adhesive agent 160 is implemented.

  Specifically, in the second connection step (S30), the reinforcing plate 140 is disposed so as to face all or a part of the portion of the second flexible printed wiring board 120 where the connection member 130 is not disposed. Then, the reinforcing plate 140 and a part of the second flexible printed wiring board 110 are mechanically connected by an adhesive 160.

  The adhesive 160 is preferably a thermosetting resin, and more preferably contains one or more types of epoxy resins and one or more types of latent curing agents.

  In the method of connecting the flexible printed wiring boards 110 and 120, the respective steps (S10 to S40) may be performed in an arbitrary order, or arbitrary steps may be performed simultaneously. From the viewpoint of facilitating connection and reducing the number of steps, it is preferable to simultaneously perform the second connection step (S30) and the third connection step (S40). In this case, after the first connection step (S20) in which the first and second flexible printed wiring boards 110 and 120 are connected by the connecting member 130, the reinforcing plate 140 and the first and second flexible printed wiring boards 110, 120 are connected. 120 is arranged to face each other. And the 1st and 2nd flexible printed wiring boards 110 and 120 and the reinforcement board 140 are connected using the adhesive agents 150 and 160. FIG. Further, the adhesives 150 and 160 may be different or the same. When the adhesives 150 and 160 are the same, they may be disposed on the surface of the reinforcing plate 140 at a time.

  By performing the above steps (S10 to S40), it is possible to obtain the flexible printed wiring board connection structure 100 in which the first and second flexible printed wiring boards 110 and 120 shown in FIG. 1 are connected.

  In the present embodiment, the connection structure of two flexible printed wiring boards and the connection method of flexible printed wiring boards have been described. However, the connection structure of three or more flexible printed wiring boards and the connection method of flexible printed wiring boards The present invention is also included. In the case of the connection structure and connection method of three or more flexible printed wiring boards, a third flexible printed wiring board is further added to the first and second flexible printed wiring boards 110 and 120, or the first and second flexible printed wiring boards are connected. By using a plurality of connection structures 100 of the two flexible printed wiring boards 110 and 120, a connection structure and a connection method for three or more flexible printed wiring boards are obtained.

  In the embodiments, the flexible printed wiring board is described as a flexible wiring board connection structure and connection method, but the present invention is not particularly limited to this. The flexible wiring board connection structure and connection method in the embodiment can be applied to a flexible flat cable (FFC). That is, the present invention can be applied to a connection structure and a connection method between flexible flat cables, a connection structure and a connection method between a flexible flat cable and a flexible printed wiring board, and the like.

  As described above, according to the connection structure 100 of the flexible printed wiring boards 110 and 120 as an example of the connection structure of the flexible wiring board in the embodiment, the first flexible printed wiring board 110 and the first flexible printed circuit. Second flexible printed wiring board 120 arranged to face wiring board 110, first flexible printed wiring board 110, and connection member 130 for electrically connecting second flexible printed wiring board 120, A surface 110b having a higher rigidity than the first and second flexible printed wiring boards 110 and 120 and a surface 110b opposite to the surface 110a on which the connection member 130 is disposed in the first flexible printed wiring board 110, Connecting member via first flexible printed wiring board 110 And a 30 and a reinforcing plate 140 that is connected all or part 110b1 of opposing portions 110b. Since the flexible printed wiring board connection structure 100 includes the reinforcing plate 140 that reinforces at least the connecting portions of the first and second flexible printed wiring boards 110 and 120, the first and second flexible printed wiring boards 110 and 120 are provided. Even when at least one of 120 has good flexibility, it is possible to prevent the first and second flexible printed wiring boards 110 and 120 (particularly the patterns 112 and 122) from being broken during bending. For this reason, the bending characteristics are improved.

  In addition, since the first and second flexible printed wiring boards 110 and 120 are connected using the connecting member 130 at a position facing each other, the size can be reduced.

  Furthermore, since the reinforcing plate 140 reinforces at least the connection portion of the first and second flexible printed wiring boards 110 and 120, the connection strength of the first and second flexible printed wiring boards 110 and 120 can be improved.

  In the flexible printed wiring board connection structure 100, the connection member 130 is preferably a thermosetting resin. Thereby, the connection of the 1st and 2nd flexible printed wiring boards 110 and 120 can be ensured. Further, when the pitch P of the patterns 112 and 122 in the first and second flexible printed wiring boards 110 and 120 is narrow, a short circuit is prevented as compared with the case where they are connected by a connecting member made of solder or thermoplastic resin. it can.

  In the flexible printed wiring board connection structure 100, the connection member 130 is preferably an anisotropic conductive film. Thereby, even when the pitch P of the patterns 112 and 122 in the first and second flexible printed wiring boards 110 and 120 is small, the first and second flexible printed wiring boards 110 and 120 are more reliably connected. Can be. Further, when the pitch P of the patterns 112, 122 in the first and second flexible printed wiring boards 110, 120 is narrow, the short circuit is more effective than the case where they are connected by a connecting member made of solder or thermoplastic resin. Can be prevented.

  In the flexible printed wiring board connection structure 100, preferably, the reinforcing plate 140 is also opposed to the portion 120a (part 120a1 in the embodiment) of the second flexible printed wiring boards 110 and 120 where the connection member 130 is not disposed. The adhesive plate 160 further includes an adhesive 160 that connects the reinforcing plate 140 and a portion of the second flexible printed wiring board 120 (part 120a1 in the embodiment). Thereby, the 2nd flexible printed wiring board 120 and the reinforcement board 140 can be connected. Therefore, the flexibility of the second flexible printed wiring board 120 can be utilized. Further, the strength of the second flexible printed wiring board 120 other than the connection portion with the first flexible printed wiring board 110 can be improved.

  In the flexible printed wiring board connection structure 100, the adhesive 160 is preferably a thermosetting resin. Thereby, the 2nd flexible printed wiring board 120 and the reinforcement board 140 can be connected more reliably.

  In the flexible printed wiring board connection structure 100, the reinforcing plate 140 is preferably made of at least one substance selected from the group consisting of polyimide, glass epoxy, paper phenol, copper, copper alloy, aluminum, and aluminum alloy. Thereby, since the rigidity of the reinforcement board 140 improves, the flexibility of the 1st and 2nd flexible printed wiring boards 110 and 120 can be utilized more.

  In the flexible printed wiring board connection structure 100, the second flexible printed wiring board 120 preferably has high flexibility. Thereby, even if the second flexible printed wiring board 120 has high flexibility, it is possible to prevent the second flexible printed wiring board 120 from being broken by the reinforcing plate 140. In addition, since the second flexible printed wiring board 120 has high flexibility, the mobility is high and a connection structure with a wider shape can be obtained.

  A flexible printed wiring board connection method as an example of a flexible wiring board connection method according to an embodiment of the present invention includes a first flexible printed wiring board 110, a second flexible printed wiring board 120, first and first flexible printed wiring boards. A preparation step (S10) for preparing a reinforcing plate having higher rigidity than the second flexible printed wiring boards 110 and 120, the first flexible printed wiring board 110, and the first flexible printed wiring board 110 so as to face each other. The first flexible printed wiring board 120 in the first flexible printed wiring board 110 and the first flexible printed wiring board 110 in the first flexible printed wiring board 110 connected to the second flexible printed wiring board 120 arranged at the connection member 130. All or part 110b1 of the surface 110b opposite to the surface 110a; And a second connecting step of connecting the plate 140 (S30). As a result, the first and second flexible printed wiring boards 110 and 120, the connection member 130 connecting the first and second flexible printed wiring boards 110 and 120, and the first flexible printed wiring boards 110 and 120, A flexible printed wiring board connection structure 100 including the reinforcing plate 140 to be connected can be obtained. Therefore, the obtained flexible printed wiring board connection structure 100 at least reinforces the connecting portions of the first and second flexible printed wiring boards 110 and 120 and the portions of the first flexible printed wiring board 110 other than the connecting portions. Since the reinforcing plate 140 is provided, even when at least one of the first and second flexible printed wiring boards 110 and 120 is flexible, the first and second flexible printed wiring boards are bent. It can prevent that 110,120 breaks. Therefore, it is possible to obtain the connection structure 100 of the flexible printed wiring board with good flexibility.

  In addition, since the first and second flexible printed wiring boards 110 and 120 are connected using the connecting member 130 at a position facing each other, the flexible printed wiring board connection structure 100 can be obtained to achieve miniaturization. .

  Preferably, the flexible printed wiring board connection method further includes a third connection step (S40) of connecting the second flexible printed wiring board 120 and the reinforcing plate 140 with the adhesive 160. By performing the third connection step (S40), the reinforcing plate 140 and the second flexible printed wiring board 120 can be connected. Therefore, the flexibility of the second flexible printed wiring board 120 can be utilized. In addition, the strength of the second flexible printed wiring board 120 other than the joint portion with the first flexible printed wiring board 110 can be improved.

  In the flexible printed wiring board connection method, preferably, the second connection step (S30) and the third connection step (S40) are performed simultaneously. Thereby, the number of processes can be reduced.

  The embodiment disclosed above should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above embodiments and examples but by the scope of claims, and is intended to include all modifications and variations within the meaning and scope equivalent to the scope of claims. .

It is a schematic sectional drawing which shows the connection structure of the flexible printed wiring board in embodiment of this invention. It is the schematic for demonstrating a sliding bending test. It is a schematic top view for demonstrating the connection method of the flexible printed wiring board in embodiment of this invention. It is a schematic sectional drawing for demonstrating the connection method of the flexible printed wiring board in embodiment of this invention. It is a flowchart which shows the connection method of the flexible printed wiring board in embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 Fixing board, 12 Holding metal fitting, 13 Drive board, 14 Disconnection detection apparatus terminal, 20 Flexible printed wiring board, 100 Flexible printed wiring board connection structure, 110 1st flexible printed wiring board, 120 2nd flexible printed wiring board 110a, 110b surface, 110b1 all or part, 120a1 part, 111,121 base film, 112,122 pattern, 113,123 adhesive, 114,124 cover film, 120a part, 130 connecting member, 140 reinforcing plate, 150,160 Adhesive, P pitch, R Bending radius.

Claims (10)

A first flexible wiring board;
A second flexible wiring board disposed to face the first flexible wiring board;
A connection member for electrically connecting the first flexible wiring board and the second flexible wiring board;
The first flexible wiring board has higher rigidity than the first and second flexible wiring boards, and is a surface opposite to the surface on which the connection member is disposed in the first flexible wiring board. A connection structure for a flexible wiring board, comprising: a reinforcing plate connected to all or a part of a portion facing the connection member via a connector.   The flexible wiring board connection structure according to claim 1, wherein the connection member is a thermosetting resin.   The connection structure of the flexible wiring board according to claim 1, wherein the connection member is an anisotropic conductive film. The reinforcing plate is also opposed to a portion of the second flexible wiring board where the connecting member is not disposed,
The connection structure of the flexible wiring board in any one of Claims 1-3 further provided with the adhesive agent which connects the said reinforcement board and the said part of a said 2nd flexible wiring board.   The connection structure for a flexible wiring board according to claim 4, wherein the adhesive is a thermosetting resin.   The flexible wiring according to claim 1, wherein the reinforcing plate is made of at least one substance selected from the group consisting of polyimide, glass epoxy, paper phenol, copper, copper alloy, aluminum, and aluminum alloy. Board connection structure.   The connection structure of the flexible wiring board according to claim 1, wherein the second flexible wiring board has high flexibility. A preparation step of preparing a first flexible wiring board, a second flexible wiring board, and a reinforcing plate having higher rigidity than the first and second flexible wiring boards;
A first connection step of electrically connecting the first flexible wiring board and the second flexible wiring board arranged to face the first flexible wiring board with a connecting member;
A flexible wiring board comprising: a second connection step for connecting all or part of a surface of the first flexible wiring board opposite to the surface connected to the second flexible wiring board and the reinforcing plate. Connection method.   The connection method of the flexible wiring board of Claim 8 further equipped with the 3rd connection process of connecting a said 2nd flexible wiring board and the said reinforcement board with an adhesive agent.   The flexible wiring board connection method according to claim 9, wherein the second connection step and the third connection step are performed simultaneously.

Images