JP2014027080A - Connection structure of printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connection structure of a printed wiring board capable of effectively reducing a size and thickness.SOLUTION: There is provided a connection structure in a printed wiring board 1 including a flexible printed wiring board 10 and a printed wiring board 20 connected to each other. The flexible printed wiring board 10 has an insertion piece S. The printed wiring board 20 has a notch K. The flexible printed wiring board 10 and the printed wiring board 20 are connected via an insertion joint C in which the insertion piece S is inserted into the notch K.

Description

  The present invention relates to a printed wiring board connection structure capable of effectively realizing a reduction in thickness and size.

Inside an electronic device such as a mobile phone or a hard disk device of a computer, a flexible printed wiring board provided with a wiring circuit formed by patterning wiring and a printed wiring board provided with a wiring circuit formed by patterning wiring (for example, flexible A printed wiring board connection structure is provided which is connected to each other.
As a prior art showing the connection structure of such a printed wiring board, for example, there is Patent Document 1 below.

JP 2006-196423 A

A conventional printed wiring board connection structure as shown in Patent Document 1 is generally formed through a connector.
More specifically, as shown in part in FIG. 10 of Patent Document 1, a terminal of the flexible printed wiring board 1 and a terminal (not shown) of another printed wiring board are connected via a connector 20. In general, a flexible printed wiring board and another printed wiring board are mechanically and electrically connected to form a printed wiring board connection structure.
Therefore, in the conventional printed wiring board connection structure using such a connector, the total thickness of the printed wiring board connection structure increases by the thickness of the connector, so the printed wiring board connection structure is made thinner. There has been a problem that miniaturization cannot be realized.

  SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a printed wiring board connection structure capable of solving the above-described conventional problems and effectively realizing a reduction in thickness and size.

  The connection structure of the printed wiring board of the present invention is a connection structure of a printed wiring board formed by connecting a flexible printed wiring board and another printed wiring board, and the flexible printed wiring board includes an insertion piece, The printed wiring board includes a cutout portion, and the flexible printed wiring board and the other printed wiring board are connected via an insertion connection portion formed by inserting the insertion piece into the cutout portion. Is the first feature.

  According to the first feature of the present invention, the connection structure of the printed wiring board is a connection structure of a printed wiring board formed by connecting a flexible printed wiring board and another printed wiring board, The wiring board includes an insertion piece, the printed wiring board includes a cutout portion, and the flexible printed wiring board and the other prints via an insertion connection portion formed by inserting the insertion piece into the cutout portion. Since the wiring board is connected to the printed wiring board, it is possible to effectively reduce the thickness and size of the printed wiring board connection structure. In addition, a printed wiring board connection structure with good mechanical connection reliability can be easily formed simply by inserting the insertion piece into the notch.

  Further, in the printed wiring board connection structure of the present invention, in addition to the first feature of the present invention, the plug-in connection portion includes a plurality of the cutout portions, and at least two of the cutout portions, A second feature is that the insertion piece is inserted from one side of another printed wiring board to the other side through the other side.

  According to the second feature of the present invention, in addition to the operational effects of the first feature of the present invention, the plug-in connection portion includes a plurality of the cutout portions, and at least two cutout portions are provided. In addition, since the insertion piece is inserted from one side of the other printed wiring board to the other side again through the other side, the connection structure of the printed wiring board is further improved in mechanical connection reliability. It can be.

  Further, in the printed wiring board connection structure of the present invention, in addition to the first or second feature of the present invention, the insertion piece includes a terminal, and the terminal and the terminal provided on the other printed wiring board are provided. The third feature is that they are electrically connected.

According to the third aspect of the present invention, in addition to the operational effects of the first or second aspect of the present invention, the insertion piece includes a terminal, and the terminal and the other printed wiring board. Since the terminals are electrically connected, electrical connection can be made in addition to mechanical connection between the flexible printed wiring board and another printed wiring board via the plug-in connection portion.
Therefore, a printed wiring board connection structure with good mechanical and electrical connection reliability can be easily formed simply by inserting the insertion piece into the notch.

  Further, the printed wiring board connection structure of the present invention is characterized in that, in addition to any one of the first to third features of the present invention, the surface of the plug connection portion is covered with an adhesive layer. It has the characteristics of

  According to the fourth feature of the present invention, in addition to the function and effect of any one of the first to third features of the present invention, the surface of the plug-in connection portion is covered with an adhesive layer. Therefore, the connection structure of the printed wiring board can be further improved with higher mechanical connection reliability. In addition, it is possible to obtain a printed wiring board connection structure that is more excellent in electrical connection reliability.

According to the printed wiring board connection structure of the present invention, it is possible to reduce the thickness and size of the printed wiring board connection structure.
Further, it is possible to easily form a printed wiring board connection structure with good mechanical connection reliability.
In addition, it is possible to easily form a printed wiring board connection structure with good electrical connection reliability.

It is a figure which shows the connection structure of the printed wiring board which concerns on the 1st Embodiment of this invention, (a) is a top view which shows the connection structure of a printed wiring board, (b) comprises the connection structure of a printed wiring board The top view which shows the flexible printed wiring board to do, (c) is a top view which shows the printed wiring board which comprises the connection structure of a printed wiring board. It is sectional drawing of the principal part in the AA line direction of Fig.1 (a). It is sectional drawing of the principal part which simplifies and shows the manufacturing process of the flexible printed wiring board which comprises the connection structure of the printed wiring board which concerns on the 1st Embodiment of this invention. It is sectional drawing of the principal part which simplifies and shows the manufacturing process of the printed wiring board which comprises the connection structure of the printed wiring board which concerns on the 1st Embodiment of this invention. It is sectional drawing of the principal part which simplifies and shows the manufacturing process of the connection structure of the printed wiring board which concerns on the 1st Embodiment of this invention. It is a figure which shows the modification of the connection structure of the printed wiring board which concerns on the 1st Embodiment of this invention, (a) is a top view which shows the connection structure of a printed wiring board, (b) is BB of (a). It is sectional drawing of the principal part in a line direction. It is a figure which shows the connection structure of the printed wiring board which concerns on the 2nd Embodiment of this invention, (a) is a top view which shows the connection structure of a printed wiring board, (b) is the flexible printed wiring board which comprises a printed wiring board (C) is a top view which shows the printed wiring board which comprises the connection structure of a printed wiring board. It is sectional drawing of the principal part in the DD line direction of Fig.7 (a). It is sectional drawing of the principal part which shows the connection structure of the conventional printed wiring board.

  With reference to the following drawings, a printed wiring board connection structure according to an embodiment of the present invention will be described for the understanding of the present invention. However, the following description is an embodiment of the present invention, and does not limit the contents described in the claims.

  First, a printed wiring board connection structure 1 according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

The printed wiring board connection structure 1 according to the first embodiment of the present invention is formed by connecting two printed wiring boards to each other, and is built in an electronic device such as a mobile phone (not shown). .
As shown in FIGS. 1 and 2, the printed wiring board connection structure 1 includes a flexible printed wiring board 10 and a printed wiring board 20.

  The flexible printed wiring board 10 is a printed wiring board connected to the printed wiring board 20, and includes a base material layer 11, a conductive layer 12, and an insulating layer 13 as shown in FIG. 2.

The base material layer 11 serves as a base of the flexible printed wiring board 10 and is formed of an insulating resin film.
As a resin film, what consists of a resin material excellent in the softness | flexibility is used. For example, any film may be used as long as it is normally used as a resin film for forming a substrate of a flexible printed wiring board, such as a polyimide film or a polyester film.
In particular, those having high heat resistance in addition to flexibility are desirable. For example, polyamide resin films, polyimide resin films such as polyimide and polyamideimide, and polyethylene naphthalate can be preferably used.
Further, as the heat resistant resin, any resin may be used as long as it is normally used as a heat resistant resin for forming a flexible printed wiring board, such as a polyimide resin or an epoxy resin.
The thickness of the base material layer 11 is desirably about 5 μm to 50 μm, more preferably 12 μm to 25 μm. This is because if it is less than 5 μm, the insulation cannot be maintained, and if it exceeds 50 μm, flexibility is lost.

The conductive layer 12 is a layer made of a conductive metal, and is a layer that forms wiring, terminals, and the like of the flexible printed wiring board 10.
In this embodiment, as shown in FIGS. 1B and 2, the insertion piece S described later includes a terminal 12 b and a wiring 12 a connected to the terminal 12 b.
The wiring 12a can be formed on the surface of the base material layer 11 by using a known forming method such as an additive method in which a conductive metal such as copper is formed by plating.
The terminal 12b can be formed by, for example, coating the surface of the wiring 12a with a conductive metal such as gold. In the present embodiment, the terminal 12b is formed by plating the surface of the wiring 12a with nickel and coating gold with plating.
The thickness of the wiring 12a is desirably about 5 to 50 μm, more preferably 12 to 35 μm. This is because if it is less than 5 μm, the electrical resistance of the wiring increases, and if it exceeds 50 μm, flexibility is lost.
The thickness of the terminal 12b is preferably about 0.05 to 20 μm, more preferably 0.1 to 10 μm. This is because if it is less than 0.05 μm, the plating is too thin and the wiring 12a corrodes, and if it exceeds 20 μm, flexibility is lost.

The insulating layer 13 is a layer for ensuring insulation of the flexible printed wiring board 10.
Although not shown in detail in the present embodiment, the insulating layer 13 is formed of an insulating resin film with an insulating adhesive.
As the insulating adhesive, any epoxy adhesive may be used as long as it is usually used as an insulating adhesive for forming an insulating layer of a flexible printed wiring board.
As the insulating resin film, any film may be used as long as it is normally used as an insulating resin film for forming an insulating layer of a flexible printed wiring board, such as a polyimide film. Further, the configuration is not necessarily limited to the configuration using the insulating resin film, and the configuration may be any configuration as long as it is normally used for forming the insulating layer of the flexible printed wiring board.
The thickness of the insulating layer 13 is desirably about 5 μm to 50 μm, more preferably 12 μm to 25 μm. This is because if it is less than 5 μm, insulation cannot be secured, and if it exceeds 50 μm, flexibility is lost.

Moreover, in this embodiment, as shown in FIG.1 (b), it is set as the structure which provides the piece S for two insertions in a part of the flexible printed wiring board 10. FIG.
More specifically, as shown in FIG. 1 (b), the insertion piece S made of an elongated rectangle extending in the longitudinal direction of the flexible printed wiring board 10 is a line orthogonal to the longitudinal direction of the flexible printed wiring board 10 (see FIG. 1 (b), which is indicated by a two-dot chain line), and two symmetrically with respect to the axis of symmetry.
As will be described later, the insertion piece S can be formed by punching the flexible printed wiring board 10 into a predetermined shape in the thickness direction using a mold.

The printed wiring board 20 is a printed wiring board connected to the flexible printed wiring board 10 and includes a base material layer 21, a conductive layer 22, and an insulating layer 23 as shown in FIG. In the present embodiment, a flexible printed wiring board is used as the printed wiring board 20.
The base material layer 21, the conductive wire layer 22 (wiring 22a, terminal 22b), and the insulating layer 23 are the base material layer 11, the conductive layer 12 (wiring 12a, terminal 12b), and insulation that constitute the flexible printed wiring board 10 described above. Since it is formed of the same member as the layer 13, the following detailed description will be omitted, and only the configuration different from the flexible printed wiring board 10 will be described.

In the present embodiment, as shown in FIGS. 1A and 1C, three cutout portions K are provided at positions corresponding to the insertion pieces S of the flexible printed wiring board 10 in the printed wiring board 20. is there.
More specifically, one cutout portion K1 made of an elongated rectangle extending in the longitudinal direction of the printed wiring board 20 is provided. Further, a notch portion K2 formed of a straight line extending in the short direction of the printed wiring board 20 passes through the center of the notch portion K1 outside the notch portion K1 and is perpendicular to the longitudinal direction of the printed wiring board 20 (FIG. 1). Two lines are provided symmetrically with respect to the axis of symmetry (indicated by a two-dot chain line in (c)).
As will be described later, the cutout portion K can be formed by punching the printed wiring board 20 into a predetermined shape in the thickness direction using a mold.
In the present embodiment, as shown in FIGS. 1C and 2, a terminal 22b is provided between the notch K1 and the notch K2.
The width E of the notch K1 and the width F of the notch K2 need to be larger than the width G of the insertion piece S. More specifically, the widths E and F of the notches K1 and K2 are preferably about 0.1% to 20% larger than the width G of the insertion piece S, and more preferably 1% to 10% larger. . If it is less than 0.1%, the insertion piece S cannot be inserted into the cutouts K1 and K2. If it exceeds 20%, the insertion piece S is inserted due to vibration or the like in the state where the printed wiring board connection structure 1 is formed. This is because the contact state between the terminal 12b and the terminal 22b may be eliminated due to the deviation of the piece S.
Further, the interval H between the notch K1 and the notch K2 needs to be shorter than the length J of the insertion piece S.
The length L of the notch K1 is preferably the same as the interval M between the two insertion pieces S or larger than the interval M by about 20% or less, more preferably by about 10% or less. If it exceeds 20%, there is a possibility that the contact state between the terminal 12b and the terminal 22b may be eliminated because the insertion piece S is displaced due to vibration or the like in the state where the printed wiring board connection structure 1 is formed. This is because any one of the two insertion pieces S cannot be inserted into the cut portion K.

By connecting the flexible printed wiring board 10 and the printed wiring board 20 having such a configuration to each other, the printed wiring board connection structure 1 according to the present embodiment is formed.
More specifically, as shown in FIG. 1A and FIG. 2, the insertion piece S is inserted into the cutout portion K so as to be orthogonal to the longitudinal direction of the flexible printed wiring board 10 (printed wiring board 20). Two insertion connections C are formed in line symmetry with the line as a symmetry axis (indicated by a two-dot chain line in FIG. 1A). As a result, the flexible printed wiring board 10 and the printed wiring board 20 are connected and fixed to each other via the two insertion connecting portions C, thereby forming the printed wiring board connection structure 1.
In the present embodiment, as shown in FIGS. 1A and 2, one side of the printed wiring board 20 (mainly with respect to the two notches K1 of the notch K1 and the notch K2). The insertion side connection portion C is formed by inserting one insertion piece S through the other side (back side) through the other side (back side) to the one side (front side) again. .
More specifically, first, the insertion piece S is inserted into the cutout portion K1 from one side (front side) to the other side (back side) of the printed wiring board 20, and the printed wiring board 20 and the like. 1 by inserting the insertion piece S into the cutout K2 from the other side (back side) to the other side (front side) through the surface side (back side). In this configuration, two plug connection portions C are formed.
In the present embodiment, as shown in FIGS. 1A and 2, the terminal 12 b of the flexible printed wiring board 10 and the terminal 22 b of the printed wiring board 20 are connected in a state where the connection structure 1 of the printed wiring board is formed. The electrical connection is made by bringing them into contact.
FIG. 2 shows the notch K2 in an enlarged manner for convenience of explanation, and the insertion piece S is bent more than the actual one.
The printed wiring board connection structure 1 formed in this way is used, for example, by being attached to a housing of an electronic device (not shown) via an adhesive (so-called adhesive tape or the like).

  The printed wiring board connection structure 1 according to the embodiment of the present invention having such a configuration has the following effects.

The insertion connecting portion C is formed by inserting the insertion piece S into the notch K, and the flexible printed wiring board 10 and the printed wiring board 20 are connected and fixed to each other via the insertion connecting portion C. By forming the connection structure 1, it is possible to effectively reduce the thickness and size of the printed wiring board connection structure 1. Therefore, it is possible to provide a printed wiring board connection structure 1 that can be suitably adapted to recent electronic devices such as cellular phones, which are remarkably thin and small.
Further, since the printed wiring board connection structure 1 can be formed simply by inserting the insertion piece S into the notch K, a separate process such as a heat treatment process is not required for connecting the flexible printed wiring board 10 and the printed wiring board 20. Therefore, it is possible to obtain a printed wiring board connection structure 1 that has high manufacturing efficiency and can realize manufacturing cost savings. In addition, since the insertion piece S is simply inserted into the notch K, the printed wiring board connection structure 1 having repairability can be obtained.
Further, the terminal 12b is provided on the insertion piece S, and the terminal 22b is provided between the notch K1 and the notch K2, so that the flexible printed wiring board 10 and the printed wiring are connected via the insertion connection C. In addition to mechanical connection with the plate 20, electrical connection can also be made. Therefore, the printed wiring board connection structure 1 having good mechanical and electrical connection reliability can be easily formed.
In addition, two insertion pieces S are provided symmetrically about a line orthogonal to the longitudinal direction of the flexible printed wiring board 10 as an axis of symmetry, and the two insertion pieces S are inserted into the corresponding notches K1 and K2. By setting it as a structure, the insertion place of the piece S for insertion can be provided in two places at a line symmetrical position. Therefore, when the printed wiring board connection structure 1 is formed, the flexible printed wiring board 10 or the printed wiring board 20 is displaced due to vibration or the like (particularly when the longitudinal displacement of the wiring board is generated). However, it is possible to effectively prevent the insertion piece S from coming out of the cutout portion K. Moreover, it can prevent effectively that the contact state of the terminal 12b and the terminal 22b is eliminated. Therefore, it is possible to obtain a printed wiring board connection structure 1 with good mechanical and electrical connection reliability.
Furthermore, with respect to the two cutout portions K, that is, the cutout portion K1 and the cutout portion K2, the other surface (back surface side) passes through the other surface side (back surface side) from the one surface side of the printed wiring board 20 again. The flexible printed wiring board 10 and the printed wiring board 20 are further strengthened by adopting a configuration in which one insertion connecting portion C is formed by inserting one insertion piece S to the side (front surface side). Can be mechanically connected. Therefore, it is possible to obtain a printed wiring board connection structure 1 that is more excellent in mechanical connection reliability. In addition, it is possible to add an elastic force toward the printed wiring board 20 to the insertion piece S. Therefore, it is possible to spontaneously press the terminal 12b provided in the insertion piece S against the terminal 22b by this elastic force, and the electrical connection between the terminal 12b and the terminal 22b is more reliably performed only by forming the insertion connection portion C. be able to. Therefore, it is possible to obtain a printed wiring board connection structure 1 that is more excellent in electrical connection reliability.

On the other hand, in the conventional printed wiring board connection structure 3 shown in FIG. 9, the terminal T of the flexible printed wiring board 4 (part of the wiring 4b) and the terminal T of the flexible printed wiring board 5 (part of the wiring 5b). Are generally mechanically and electrically connected via a connector 6.
Therefore, since the total thickness of the printed wiring board connection structure 3 increases by the thickness of the connector 6, there is a problem in that the printed wiring board connection structure 3 cannot be reduced in thickness and size.
The base material layer 4a, the wiring 4b, the insulating layer 4c of the flexible printed wiring board 4 constituting the conventional printed wiring board connection structure 3 and the base material layer 5a, the wiring 5b, and the insulating layer 5c of the flexible printed wiring board 5 are already provided. Since it is formed of the same member as the base material layer 11, the wiring 12a, and the insulating layer 13 of the flexible printed wiring board 10 described above, the following detailed description will be omitted.

  Therefore, by adopting the configuration of the printed wiring board connection structure 1 according to the first embodiment of the present invention, the printed wiring board connection structure can be effectively reduced in thickness and size.

  Next, with reference to FIGS. 3-5, the manufacturing method of the connection structure 1 of the printed wiring board which concerns on the 1st Embodiment of this invention is demonstrated.

First, with reference to FIG. 3, the manufacturing process of the flexible printed wiring board 10 which comprises the connection structure 1 of the printed wiring board which concerns on the 1st Embodiment of this invention is demonstrated.
With reference to Fig.3 (a), the base material layer 11 which consists of an insulating resin film is prepared.
Next, referring to FIG. 3B, a wiring 12 a made of a conductive metal such as copper is formed on the surface of the base material layer 11 using a known forming method (for example, an additive method).
Next, with reference to FIG.3 (c), the insulating layer 13 is formed by coat | covering the insulating resin film with an insulating adhesive agent on the surface of the base material layer 11 and the wiring 12a. At this time, as shown in FIGS. 3C and 3D, the insulating layer 13 is formed so that the surface of the wiring 12a that will later form the terminal 12b is exposed.
Next, referring to FIG. 3D, the surface of the exposed wiring 12a is covered with gold by using a known plating method (for example, electrolytic plating) to form the terminal 12b.
Next, referring to FIG. 3 (e), a flexible printed wiring board 10 having the insertion piece S shown in FIG. 1 (b) is obtained by punching out a predetermined area of the wiring board into a predetermined shape using a mold (not shown). Is formed.

Next, with reference to FIG. 4, the manufacturing process of the printed wiring board 20 which comprises the connection structure 1 of the printed wiring board which concerns on the 1st Embodiment of this invention is demonstrated.
With reference to Fig.4 (a), the base material layer 21 which consists of an insulating resin film is prepared.
Next, referring to FIG. 4B, a wiring 22 a made of a conductive metal such as copper is formed on the surface of the base material layer 21 using a known forming method (for example, an additive method).
Next, with reference to FIG.4 (c), the insulating layer 23 is formed by coat | covering the insulating resin film with an insulating adhesive agent on the surface of the base material layer 21 and the wiring 22a. At this time, as shown in FIGS. 4C and 4D, the insulating layer 23 is formed so that the surface of the wiring 22a that will later form the terminal 22b is exposed.
Next, referring to FIG. 4D, the surface of the exposed wiring 22a is covered with gold using a known plating method (for example, electrolytic plating) to form the terminal 22b.
Next, referring to FIG. 4E, a printed wiring board 20 having a notch K shown in FIG. 1C is formed by punching out a predetermined area of the wiring board into a predetermined shape using a mold. The

Next, with reference to FIG. 5, the formation method of the connection structure 1 of the printed wiring board formed by connecting the flexible printed wiring board 10 and the printed wiring board 20 will be described.
First, referring to FIG. 5A, the flexible printed wiring board 10 is prepared above the printed wiring board 20.
Next, referring to FIG. 5 (b), the other surface from the one surface side (front surface side) of the printed wiring board 20 to the two notch portions K of the notch portion K1 and the notch portion K2. Two insertion connection portions C are formed by inserting one insertion piece S through the side (back surface side) to the one surface side (front surface side) again.
As a result, the printed wiring board connection structure 1 is formed by mechanically and electrically connecting the flexible printed wiring board 10 and the printed wiring board 20.
FIG. 5 shows the notch K2 in an enlarged manner for convenience of explanation, and the insertion piece S is bent more than the actual one.

Next, a modified example of the printed wiring board connection structure 1 according to the first embodiment of the present invention will be described with reference to FIG.
In this modified example, the surface of the insertion connection portion C is covered with the adhesive layer 30 with respect to the connection structure 1 for the printed wiring board according to the first embodiment of the present invention described above.
Since the other configuration is the same as the printed wiring board connection structure 1 according to the first embodiment of the present invention described above, the same member and the same function are given the same number and the same alphabet, The following detailed description will be omitted.
FIG. 6B shows the notched portion K2 in an enlarged manner for the sake of convenience of explanation, and the insertion piece S is bent larger than the actual one.

  Referring to FIG. 6A, in this modification, a predetermined region on the back surface side including the insertion connection portion C in the printed wiring board connection structure 1 (region indicated by a one-dot chain line in FIG. 6A). Is configured to be integrally covered with the adhesive layer 30. In addition, in this modification, it is set as the structure which forms the adhesive bond layer 30 with an adhesive tape.

With such a configuration, the insertion piece S can be more firmly fixed to the printed wiring board 20. Therefore, the flexible printed wiring board 10 and the printed wiring board 20 can be mechanically and electrically connected more firmly.
Accordingly, it is possible to obtain a printed wiring board connection structure 1 that is further excellent in mechanical and electrical connection reliability.

Next, a printed wiring board connection structure 2 according to a second embodiment of the present invention will be described with reference to FIGS.
The printed wiring board connection structure 2 according to the present embodiment is different from the above-described printed wiring board connection structure 1 according to the first embodiment of the present invention only in the configuration of the insertion piece and the cutout portion. It is a configuration.
Since the other configuration is the same as the printed wiring board connection structure 1 according to the first embodiment of the present invention described above, the same member and the same function have the same last digit number and alphabet. The following detailed description will be omitted.
FIG. 8 shows the cutout portion K3 in an enlarged manner for convenience of explanation, and the insertion piece S1 is bent more than the actual one.

With reference to FIG. 7, in the printed wiring board connection structure 2 according to this embodiment, the flexible printed wiring board 40 is provided with four insertion pieces S1, and the printed wiring board 50 is provided with four insertion pieces S1. Corresponding four cutouts K3 are provided. Then, the four insertion pieces S1 are respectively inserted into the four cutout portions K3 to form four insertion connection portions C, and the flexible printed wiring board 40 and the printed wiring board 50 are connected via the four insertion connection portions C. Are mechanically and electrically connected.
More specifically, referring to FIG. 7B, in the flexible printed wiring board 40, the insertion piece S <b> 1 made of an elongated rectangle extending in the short direction is connected to the flexible printed wiring board 40 in the short direction. Two lines (a pair) are provided symmetrically with respect to a vertical bisector of width (indicated by a one-dot chain line in FIG. 7B), and a line orthogonal to the longitudinal direction of the flexible printed wiring board 40 (FIG. 7). Two insertion pieces S1 (two pairs) are provided in line symmetry with the two insertion pieces S1 described above with the axis of symmetry as indicated by a two-dot chain line in (b).
Referring to FIG. 7C, in the printed wiring board 50, the notch portion K3 formed of a straight line extending in the longitudinal direction of the printed wiring board 50 is set to be perpendicular to the width of the printed wiring board 50 in the short direction. Two lines (a pair) are provided symmetrically with respect to a branch line (indicated by a one-dot chain line in FIG. 7B) and a line perpendicular to the longitudinal direction of the printed wiring board 50 (two points in FIG. 7B). The two notches K3 described above with the axis of symmetry (shown by a chain line) as the symmetry axis and two notches K3 in line symmetry (two pairs) are provided.
Further, as shown in FIGS. 7 and 8, in the flexible printed wiring board 40, terminals 42b are provided on each of the four insertion pieces S1. In the printed wiring board 50, the terminal 52b is provided at a position corresponding to (in contact with) the terminal 42b in a state where the four insertion pieces S1 are inserted into the four cutout portions K3.
Further, in the printed wiring board connection structure 2 according to the present embodiment, as shown in FIGS. 7A and 8, a predetermined region on the back surface side including the insertion connection portion C in the printed wiring board connection structure 2 ( The region indicated by the alternate long and short dash line in FIG. 7A is integrally covered with the adhesive layer 60. In addition, in this embodiment, it is set as the structure which forms the adhesive bond layer 60 with an adhesive tape.

In this way, the flexible printed wiring board 40 and the printed wiring board 50 are connected to each other at multiple points by providing the four insertion connecting portions C at line symmetrical positions in the longitudinal direction and the short direction of the wiring board. Can be fixed. Therefore, in the state in which the printed wiring board connection structure 2 is formed, even when the flexible printed wiring board 40 or the printed wiring board 50 is displaced due to vibration or the like, the insertion piece S1 is pulled out from the notch K3. This can be prevented more effectively. Further, it is possible to effectively prevent the contact state between the terminal 42b and the terminal 52b from being eliminated. Therefore, it is possible to obtain a printed wiring board connection structure 2 that is more excellent in mechanical and electrical connection reliability.
Further, a predetermined region on the back surface side (including a region indicated by a one-dot chain line in FIG. 7A) including the insertion connection portion C in the printed wiring board connection structure 2 is integrally covered with the adhesive layer 60. Thus, the insertion piece S1 can be more firmly fixed to the printed wiring board 50. Therefore, the flexible printed wiring board 40 and the printed wiring board 50 can be mechanically and electrically connected more firmly. Therefore, it is possible to obtain a printed wiring board connection structure 2 that is more excellent in mechanical and electrical connection reliability.

In the present embodiment, the flexible printed wiring board is used as the printed wiring board connected to the flexible printed wiring board having the insertion piece. However, the present invention is not necessarily limited to such a configuration. It is good also as a structure using other printed wiring boards, such as a printed wiring board.
Further, the shape, number, formation position, and formation method of the insertion pieces and the cut portions are not limited to those of the present embodiment, and can be appropriately changed.
Further, the number of wirings, terminals, and formation positions are not limited to those of the present embodiment, and can be changed as appropriate.
Further, in the modification of the first embodiment and the second embodiment of the present invention, the adhesive layer is provided on the back surface side of the printed wiring board connection structure. Instead, an adhesive layer may be provided on the front surface side of the printed wiring board connection structure.

  According to the present invention, since the connection structure of the printed wiring board can be reduced in thickness and size, the industrial applicability in the field of electronic devices incorporating the connection structure of the printed wiring board is high.

DESCRIPTION OF SYMBOLS 1 Connection structure of printed wiring board 2 Connection structure of printed wiring board 3 Connection structure of printed wiring board 4 Flexible printed wiring board 4a Base material layer 4b Wiring 4c Insulating layer 5 Flexible printed wiring board 5a Base material layer 5b Wiring 5c Insulating layer 6 Connector 10 Flexible printed wiring board 11 Base material layer 12 Conductive layer 12a Wiring 12b Terminal 13 Insulating layer 20 Printed wiring board 21 Base material layer 22 Conductive layer 22a Wiring 22b Terminal 23 Insulating layer 30 Adhesive layer 40 Flexible printed wiring board 41 Base material Layer 42 Conductive layer 42a Wiring 42b Terminal 43 Insulating layer 50 Printed wiring board 51 Base layer 52 Conductive layer 52a Wiring 52b Terminal 60 Adhesive layer C Insertion connection E Width F Width G Width H Interval J Length K Notch K1 Notch K2 Notch K3 Notch L Length M Interval S Insertion piece S1 Insertion piece T Terminal

Claims (4)

  A connection structure of a printed wiring board formed by connecting a flexible printed wiring board and another printed wiring board, wherein the flexible printed wiring board includes a piece for insertion, and the printed wiring board includes a notch, A connection structure for a printed wiring board, wherein the flexible printed wiring board and the other printed wiring board are connected via an insertion connecting portion formed by inserting the insertion piece into the cutout portion.   The insertion connecting portion includes a plurality of the cutout portions, and the insertion piece is inserted from one surface side of the other printed wiring board to the other surface side again with respect to at least two of the cutout portions. The printed wiring board connection structure according to claim 1, wherein:   The printed wiring board connection structure according to claim 1, wherein the insertion piece includes a terminal, and the terminal and a terminal provided in the other printed wiring board are electrically connected.   The printed wiring board connection structure according to any one of claims 1 to 3, wherein a surface of the plug-in connection portion is covered with an adhesive layer.

Images