JP2010287658A - Flexible printed board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To more inexpensively provide a flexible printed board targeting, as a connection object, a substrate to be connected which has terminals to be connected on surfaces different from each other of insulating sheets. <P>SOLUTION: The flexible printed board 11 targets, as a connection object, a membrane sheet 42 having terminals 45a to be connected on opposite surfaces of the insulating sheets 42a, 42b, and has connection terminals 25 to be connected to the terminals 45a to be connected on one end part surface of a base film 12 made of an insulator. The base film 12 has a first tongue part 22 and a second tongue part 23 adjoining each other across a slit 21 formed from one end edge of the base film, and the first tongue part 22 and second tongue part 23 have the connection terminals 25 to be connected to the terminals 45a to be connected on surfaces on the same side of the base film 12, and the connection terminals 25 are folded into two across the slit 21 and bonded together so that the connection terminals are arranged outside. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a flexible printed circuit board to which a connection target board having connection target terminals on different surfaces of an insulating sheet is to be connected.

  Conventionally, a connected substrate called a membrane sheet is used for a keyboard unit provided in a notebook personal computer or the like. As shown in FIG. 11, the membrane sheet 1 has a two-layer structure having a pair of an upper insulating sheet 2 and a lower insulating sheet 3 facing each other. The upper insulating sheet 2 and the lower insulating sheet 3 are provided with wiring on the surfaces facing each other, and necessary portions are insulated so that the contacts facing each other come into contact with each other when the key is pressed. It has become.

  A connecting portion for outputting a signal to the outside is formed at the end of the membrane sheet 1. This connecting portion has a structure in which the connected terminal 4 provided on the upper insulating sheet 2 and the connected terminal 4 provided on the lower insulating sheet 3 are arranged to face each other. .

  The flexible printed circuit board 8 connected to the connection portion of the membrane sheet 1 needs to be provided with connection terminals 6 a on both surfaces of the base film 5 so as to correspond to the connection portion of the membrane sheet 1. For this reason, conventionally, the connection terminals 6a are provided on both surfaces of the base film 5 by printing the wiring patterns 6 on both surfaces of the base film 5 made of an insulator.

Utility Model Registration No. 3098782

  However, the flexible printed circuit board 8 on which the wiring pattern 6 is printed on both surfaces of the base film 5 requires a protective layer 7 on the surface of the wiring pattern 6 as shown in FIG. There is a problem. For example, when the above-described membrane sheet is to be connected, a flexible printed circuit board having a five-layer structure must be prepared, and the manufacturing cost is significantly higher than a single-sided printed circuit board. There was a problem.

  The problem that the structure as described above becomes complicated is not limited to the case where a pair of insulating sheets 2 and 3 having the connected terminals 4 on the surfaces facing each other is connected. Any flexible printed circuit board that can be connected to connected boards that have connected terminals on different surfaces of the insulating sheet, such as those that have connected terminals on both sides of the insulating sheet. It is.

  Therefore, in view of such a conventional problem, the present invention is intended to connect a substrate to be connected having a connection terminal on each of different surfaces of the insulating sheet without incurring problems such as high manufacturing costs. An object of the present invention is to provide a flexible printed circuit board.

  The flexible printed circuit board according to the present invention for solving the above-described problems and achieving the intended purpose is to connect a connected board having connected terminals respectively on different surfaces of the insulating sheet, and to have an insulating property. A flexible printed circuit board having a connection terminal connected to each connected terminal of the insulating sheet on one end surface of the base film, the base film passing through a slit formed from one edge of the base film. The first piece portion and the second piece portion that are adjacent to each other, and the first piece portion and the second piece portion are each a connection terminal for connecting to a connected terminal on the same surface of the base film. It is characterized in that these connection terminals are overlapped and bonded in half through the slit so that they are arranged on different surfaces.

  Further, according to a preferred aspect of the present invention, the first piece portion and the second piece portion are arranged in such a manner that the connection terminal of the first piece portion and the connection terminal of the second piece portion are arranged outside each other. It is desirable to overlap in a fold.

  According to a preferred aspect of the present invention, the first piece portion and the second piece portion have a terminal portion provided with the connection terminal on one end portion side of the base film, and more than the terminal portion. It is desirable that the proximal end side has a bonding portion at a portion where a predetermined non-bonding region is secured, and the bonding portions are bonded to each other.

  According to the present invention, the connection terminals are provided on the same surface of the base film, and the first piece and the second piece are connected to each other through the slit so that these connection terminals are arranged on different surfaces. Because it is only necessary to overlap and fold and bond, it is possible to connect to a connected substrate that has connected terminals on different surfaces of an insulating sheet such as a membrane sheet, etc., by a simple printed flexible printed circuit board It becomes.

FIG. 1 is a plan view showing a flexible printed circuit board according to an embodiment of the present invention. FIG. 2 is a plan view showing the back surface of the flexible printed circuit board. FIG. 3 is a plan view showing a state in which the keyboard connecting portion of the flexible printed circuit board is folded in half. FIG. 4 is a perspective view showing an arrangement structure when the flexible printed circuit board is attached to the notebook computer. FIG. 5 is a cross-sectional view showing an arrangement state of the flexible printed circuit board. FIG. 6 is a cross-sectional view showing a connection state of the flexible printed circuit board. FIG. 7 is a cross-sectional view showing a connection state of the flexible printed circuit board. FIG. 8 is a plan view for explaining the connection of the flexible printed circuit board. FIG. 9 is a plan view showing a connection state of the flexible printed circuit board. FIG. 10 is a plan view showing a state in which the keyboard unit is viewed from the back side. FIG. 11 is a cross-sectional view showing a state in which a conventional flexible printed circuit board is connected to a membrane sheet which is a connected substrate.

  Hereinafter, an embodiment of a flexible printed circuit board according to the present invention will be described in detail with reference to FIGS.

  4 to 5, the flexible printed board 11 illustrated here electrically connects the membrane sheet (connected board) 42 of the keyboard unit 41 and the main board 51 such as a motherboard in the notebook personal computer A. Is to do. The keyboard unit 41 is disposed above the main board 51 in the notebook computer A. In particular, the flexible printed board 11 exemplified in the present embodiment electrically connects the connection part 45 formed at the rear end part of the keyboard unit 41 and the terminal part 52 formed on the upper surface of the main board 51. To connect.

  As shown in FIG. 7, the keyboard unit 41 includes a bottom plate 44, a membrane sheet 42 disposed on the top surface of the bottom plate 44, and a so-called keyboard key top 43 disposed on the top surface of the membrane sheet 42. have.

  As shown in FIG. 6, the membrane sheet 42 includes an upper insulating sheet (insulating sheet) 42 a and a lower insulating sheet (insulating sheet) 42 b that are each formed of an insulating material. The upper insulating sheet 42a and the lower insulating sheet 42b are provided with desired wirings on the surfaces facing each other, and are overlapped with each other via an insulating spacer sheet (not shown). A spacer sheet (not shown) is cut out at a portion corresponding to the key top 43, and when the key top 43 is pressed, the contact portion of the upper insulating sheet 42a and the contact portion of the lower insulating sheet 42b. And the circuits provided in both insulating sheets 42a and 42b are connected.

  At the end of the membrane sheet 42, a connection portion 45 is formed for outputting a signal indicating that the key top 43 is pressed to the outside. The connecting portion 45 has a structure in which the connected terminal 45a disposed on the upper insulating sheet 42a and the connected terminal 45a disposed on the lower insulating sheet 42b are arranged to face each other. Yes.

  The flexible printed circuit board 11 to be connected to the connection portion 45 is formed by forming a wiring pattern 13 with a conductor such as a copper foil only on one surface of a sheet-like base film 12 made of an insulator such as polyimide. It is what is called single-sided printing formed by providing a protective layer. As shown in FIGS. 1 and 2, the flexible printed circuit board 11 of the present embodiment is formed in a sheet shape, and a keyboard connection portion 15 is formed at one end portion thereof, while the other end portion from the keyboard connection portion 15 is formed. The first extending portion 16 and the second extending portion 17 are formed by branching into a bifurcated shape toward the portion. A main substrate connecting portion 18 is formed at the tip of the first extending portion 16, and a stick substrate connecting portion 19 is formed at the tip of the second extending portion 17.

  One end of the keyboard connecting portion 15 is divided into left and right by a slit 21 formed from one end edge of the base film 12, and the first piece 22 and the second piece are adjacent to each other through the slit 21. 23 is configured. The first piece portion 22 and the second piece portion 23 are connected to each other by a bent portion 24 located at the back side portion of the slit 21.

  A terminal portion 22a, a folded portion 22b, and an adhesive portion 22c are sequentially formed at one end portion of the first piece portion 22. The terminal portion 22 a is configured by arranging a plurality of connection terminals 25 along the one end edge of the first piece portion 22. The plurality of connection terminals 25 are not covered with the protective layer described above, and can be electrically connected by contact. The folded portion 22 b of the first piece portion 22 is a portion that is bent when connected to the keyboard unit 41. A pair of through holes 26 and a pair of mounting grooves 27 are formed in the folded portion 22b. Two through holes 26 penetrate the front and back of the base film 12, and two through holes 26 are arranged in parallel along one edge of the first piece 22. The mounting groove 27 is a groove-shaped notch formed from both ends of the portion that becomes the folded portion 22 b in the first piece portion 22. A positioning hole 28 is formed in the bonding portion 22 c of the first piece portion 22. The positioning hole 28 is formed so as to penetrate the front and back of the first piece 22.

  The second piece portion 23 is a portion formed so as to overlap the first piece portion 22 when folded back via a folding line L passing through the slit 21 and the bent portion 24. Similarly to the first piece portion 22, the second piece portion 23 is also provided with a terminal portion 23a, a folded portion 23b, and an adhesive portion 23c in this order. The terminal portion 23 a is configured by arranging a plurality of connection terminals 25 along the one end edge of the second piece portion 23. The plurality of connection terminals 25 are not covered with the protective layer, similarly to the first piece 22. As is clear from FIG. 1, the connection terminal 25 of the second piece 23 is disposed on the surface of the base film 12 that is the same as the connection terminal 25 of the first piece 22. A pair of through holes 26 and a pair of mounting grooves 27 are also formed in the folded portion 23 b of the second piece portion 23. The two through holes 26 penetrate the front and back of the base film 12, and two side holes 26 are arranged side by side along one edge of the second piece portion 23. The mounting groove 27 is a groove-shaped notch formed from both ends of the portion that becomes the folded portion 22 b in the second piece portion 23. A positioning hole 28 is formed in the bonding portion 23 c of the second piece portion 23. The positioning hole 28 is formed so as to penetrate the front and back of the second piece portion 23.

  The through-hole 26, the mounting groove 27, and the positioning hole 28 are formed at positions symmetrical to each other with the folding line L interposed therebetween, and each of the through-holes 26, the mounting groove 27, and the positioning hole 28 overlaps each other when folded through the folding line L. Become. That is, as shown in FIG. 3, when the second piece 23 is folded over the first piece 22 via the folding line L, the terminal portion 23a and the terminal portion 22a, and the folded portion 23b and the folded portion. 22b, the bonding portion 23c and the bonding portion 22c are overlapped with each other, and the through hole 26, the mounting groove 27, and the positioning hole 28 formed in the first piece portion 22 are respectively formed in the second piece portion 23. The formed through hole 26, mounting groove 27 and positioning hole 28 are overlapped with each other. However, in the present embodiment, the terminal portion 22 a of the first piece portion 22 is formed to be slightly longer than the second piece portion 23. Therefore, as shown in FIG. 3, when the second piece portion 23 is folded over the first piece portion 22 via the folding line L, the terminal portion 22 a of the first piece portion 22 becomes the second piece portion. 23 slightly protrudes from the terminal portion 23a.

  The first extending portion 16 is provided with a main substrate connecting portion 18 for connecting to the main substrate 51 at the extending end portion, and the second extending portion 17 is provided with the extending end portion in FIG. A stick substrate connecting portion 19 for connecting to the stick substrate 61 on which the pointing stick shown in FIG.

  When the flexible printed circuit board 11 configured as described above is connected to the connection part 45 of the membrane sheet 42, the first piece part 22 and the second piece part 23 are folded in two through the folding line L. Use. In this case, if the first piece 22 and the second piece 23 are folded so that the connection terminal 25 of the first piece 22 and the connection terminal 25 of the second piece 23 are respectively located outside, the membrane In the sheet 42, the individual connected terminals 45a arranged on the mutually opposing surfaces of the insulating sheets 42a, 42b, that is, the individual connected terminals 45a arranged on different surfaces of the insulating sheets 42a, 42b. The flexible printed circuit board 11 provided with the connection terminal 25 connected to is configured.

  When the first piece 22 and the second piece 23 are folded in two via the folding line L, the positioning holes 28 provided in each of the first piece 22 and the second piece 23 are provided. If a single rod-shaped positioning tool is penetrated, the mutual positions can be accurately positioned. When positioning of both is completed, what is necessary is just to adhere | attach the 1st piece part 22 and the 2nd piece part 23 with the adhesive agent 31 via mutual adhesion part 22c, 23c.

  5-7 shows the principal part of the state which connected the flexible printed circuit board 11 with respect to the membrane sheet 42. FIG. The flexible printed circuit board 11 in which the terminal portions 22a and 23a are inserted into the connection portion 45 of the membrane sheet 42 is bent through the folded portions 22b and 23b as shown in FIGS. The second extending portion 17 is disposed below the bottom plate 44. In this case, since the terminal portion 22a of the first piece portion 22 is formed slightly longer than the terminal portion 23a of the second piece portion 23, if the first piece portion 22 is bent so as to be on the outer peripheral side, the bent portion In this state, the edge of the terminal portion 22a in the first piece 22 and the edge of the terminal portion 23a in the second piece 23 can be aligned with each other. Moreover, in the 1st piece part 22 and the 2nd piece part 23, the non-bonding area | regions of the terminal parts 22a and 23a and the folding | returning parts 22b and 23b are ensured in the one end part side rather than the adhesion parts 22c and 23c. Accordingly, since the terminal portions 22a and 23a and the folded portions 22b and 23b can move relative to each other when folded at the folded portions 22b and 23b, not only can the operation be performed easily, but also the first piece disposed on the outer peripheral side. A situation in which a load is applied to the wiring pattern 13 of the portion 22 can be prevented.

  As shown in FIGS. 8 and 9, when the flexible printed circuit board 11 is connected to the connection portion 45 of the membrane sheet 42, a pair formed on the bottom plate 44 of the keyboard unit 41 in the mounting groove 27 of the flexible printed circuit board 11. When the protrusions 44 a are engaged, the membrane sheet 42 can be positioned via the bottom plate 44. That is, when the mounting groove 27 of the flexible printed circuit board 11 is engaged with the protrusion 44a, the positions of the flexible printed circuit board 11 in the front-rear direction and the left-right direction with respect to the bottom plate 44 are defined. Therefore, as long as the membrane sheet 42 is positioned in the front-rear direction and the left-right direction with respect to the bottom plate 44, the membrane sheet 42 and the flexible printed circuit board 11 can be positioned. 45a and the connection terminal 25 of the flexible printed circuit board 11 are accurately connected.

  The flexible printed circuit board 11 after being connected to the membrane sheet 42 is further folded in the opposite direction near the center of the extending direction of the first extending part 16 on the lower side of the bottom plate 44, and the main board connection at the folded tip part The part 18 is connected to the terminal part 52. The main board connection unit 18 is connected to the terminal unit 52 via a connection socket 18 a installed in the main board connection unit 18. Thus, since the flexible printed circuit board 11 can be folded back, the installation position of the main board 51 terminal portion 52 on the main board 51 can have a certain degree of freedom.

  As described above, according to the above-described flexible printed circuit board 11, the connection terminals 25 and 25 are provided on the same surface of the base film 12, and these connection terminals 25 and 25 are disposed on the outer surfaces. In this way, the first piece 22 and the second piece 23 are folded in two and bonded through the slit 21 so that the structure can be manufactured by single-sided printing with a simple structure, and the upper insulating sheet It becomes possible to provide the membrane sheet 42 having the connected terminals 45a on each of the 42a and the lower insulating sheet 42b at low cost.

  In the above-described embodiment, the membrane sheet 42 having the pair of insulating sheets 42a and 42b facing each other and having the connected terminals 45a on the surfaces facing each other of the insulating sheets 42a and 42b is connected. Although the subject flexible printed circuit board is illustrated, the present invention is not limited to this. For example, it is possible to connect a connected substrate having connected terminals on both front and back surfaces of a single insulating sheet. In this case, for example, the flexible printed circuit board 11 shown in the embodiment is applied as it is, and the first connecting terminal 25 of the first piece 22 and the connecting terminal 25 of the second piece 23 are positioned inside each other. If the piece 22 and the second piece 23 are folded, it is possible to cope.

DESCRIPTION OF SYMBOLS 11 Flexible printed circuit board 12 Base film 13 Wiring pattern 15 Keyboard connection part 16 1st extension part 17 2nd extension part 18 Main board connection part 18a Connection socket 19 Stick board connection part 21 Slit 22 First piece part 22a Terminal part 22b Folded part 22c Adhered part 23 Second piece part 23a Terminal part 23b Folded part 23c Adhered part 24 Folded part 25 Connection terminal 26 Through hole 27 Mounting groove 28 Positioning hole 31 Adhesive 41 Keyboard unit 42 Membrane sheet 42a Upper insulation Sheet 42b Lower insulating sheet 43 Key top 44 Bottom plate 44a Projection part 45 Connection part 45a Connected terminal 51 Main board 52 Main board terminal part 52 Terminal part 61 Stick board

Claims (3)

Connections to be connected to connected substrates each having connected terminals on different surfaces of the insulating sheet, and connected to each connected terminal of the insulating sheet on one end surface of the insulating base film A flexible printed circuit board having terminals,
The base film has a first piece and a second piece that are adjacent to each other through a slit formed from one edge of the base film,
The first piece portion and the second piece portion each have a connection terminal for connecting to a connected terminal on the same surface of the base film, and these connection terminals are arranged on different surfaces. As described above, a flexible printed circuit board characterized by being folded and bonded in two through the slit.     2. The first piece portion and the second piece portion are folded in two so that the connection terminal of the first piece portion and the connection terminal of the second piece portion are arranged outside each other. A flexible printed circuit board according to 1.   Said 1st piece part and said 2nd piece part have a terminal part which provided the said connecting terminal in the one end part side of the said base film, and it is a base end side rather than this terminal part, and is a predetermined | prescribed non-adhesion area | region The flexible printed circuit board according to claim 1, wherein the flexible printed circuit board has an adhesive portion at a portion where the resistance is secured, and is bonded to each other at the adhesive portion.

Images