JP2000174403A - Three-dimensional wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To electrically and mechanically connect a circuit board and other conductive patterns stably and easily with high reliability to increase the assembly work efficiency by electrically connecting the circuit board and other conductive patterns using the elasticity of the material of the circuit board made by injection molding of plastic. SOLUTION: A three-dimensional substrate 1 is made by injection molding of plastic and is formed with a connection section 2, positioning and pressing sections 3, and spheric projections 5 as integral parts of it. At necessary places on an upper face of the substrate, desired conductive patterns are formed of a thin film layer made of copper, etc. The spheric projections 5 and extraction patterns 6 are formed with conductive patterns and the connection section 2 is formed with a plurality of cutouts 4 for obtaining the elasticity. The connection section 2 is formed into a plurality of independent tongue-like parts by the cutouts 4. Walls 7-9 of the positioning and pressing sections 3 are formed on both ends of the connection section 2 to determine the layout of other conductive patterns to be connected to the substrate 1. The pattern layout in the (y) direction is made at a distance between the wall 8 and the spheric projections 5 and the conductive patterns are connected to the substrate 1 under contact pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection structure for a three-dimensional wiring board having a conductive pattern formed on a plastic substrate.

[0002]

2. Description of the Related Art In general, many circuit boards have a conductive pattern formed of copper foil or the like on a flat surface such as a glass epoxy plate or a polyimide plate. However, in recent years, three-dimensional wiring boards have been proposed in which a heat-resistant plastic material is injection-molded to form a three-dimensional shape and a conductive pattern is formed on the surface thereof.
It is known as an nterconnect Device board (hereinafter, abbreviated as “MID board”). Since a conductive pattern can be formed on a three-dimensional object, it is possible to integrate a structural component and a wiring component, and it is expected that the device will be reduced in size and the like.

On the other hand, conventionally, as a method of electrically connecting a circuit board to another conductive pattern (for example, another circuit board or a structural component such as a liquid crystal display), a method of connecting an opposing conductive pattern and applying pressure thereto has been used. A pressure welding method for obtaining a stable connection is known.

FIG. 8 shows a conventional example in which a circuit board 81 and a liquid crystal display 82 are electrically connected by pressure welding. In FIG. 8, reference numeral 83 denotes a rubber connector that can conduct electricity only in the vertical direction in the figure, and reference numeral 84 denotes a spring member that applies a compressive force to the circuit board 81, the liquid crystal display 82, and the rubber connector 83. The rubber connector 83, which is an elastic member, is contracted by the compressive force of the spring member 84, and a stable electric connection can be obtained by applying pressure to the conductive patterns of the circuit board 81 and the liquid crystal display 82. However, such a pressing method requires a rubber connector and a spring member, and also requires a member (not shown) for positioning the opposing conductive patterns.

[0005]

However, in the above-mentioned conventional example, the number of components for connecting the circuit board to another conductive pattern increases, and the assembly becomes complicated, resulting in poor workability and high cost. was there.

The problem to be solved by the present invention is to easily and reliably connect a circuit board to another conductive pattern.
An object of the present invention is to provide a wiring board capable of reducing costs by improving assembly workability, reducing costs by reducing parts, and reducing the size of equipment.

[0007]

In order to solve the above-mentioned problems, the invention according to the present application provides a three-dimensional wiring board with a spring property (elastic force), and the pressure is applied to the conductive pattern on the circuit board. Characterized by stabilizing the connection with the conductive pattern.

Further, by integrally forming the positioning members and the fixing members for the conductive patterns on the three-dimensional wiring board, it is possible to easily connect the circuit board to other conductive patterns with a small number of components.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] FIG. 1 is a perspective view of a connecting portion of a three-dimensional wiring board which best illustrates the features of the present invention. Reference numeral 1 denotes a three-dimensional wiring substrate, and a connection part 2, a positioning / pressing part 3, and a spherical projection part 5 are integrally formed by injection molding of plastic, which is an insulating material, to form a connection part. A thin film layer of copper or the like is formed on a required portion of the upper surface by a plating method, a vapor deposition method, or the like, and a desired conductive pattern is formed by an etching method or the like. This step is known as a method for manufacturing an MID substrate.

In this manner, the conductive pattern is formed on the spherical projection 5 and the lead pattern 6, and a plurality of cuts 4 are formed in the connecting portion to obtain an elastic force. Are three-dimensional wiring boards formed as independent tongue-shaped pieces by the cut portions 4.

The positioning and pressing portions 3 are provided at both ends of the connecting portion, and are composed of three walls 7, 8, 9 orthogonal to each other. Another conductive pattern (other circuit board, liquid crystal display, or the like) connected to the three-dimensional wiring board 1 is such that the wall 7 of the positioning / pressing portion 3 performs positioning in the z direction and the wall 9 performs positioning in the x direction. Leads to the correct connection position.
Further, the positioning in the y direction and the contact pressure are generated at the interval between the wall 8 and the spherical projection 5.

FIG. 2 is a top view of the three-dimensional wiring board and other conductive patterns according to the first embodiment of the present invention, showing a state before the three-dimensional wiring board 1 and the liquid crystal display 10 are connected. The liquid crystal display 10 is composed of two glass substrates, and has a conductive pattern array 11 on the back surface of the paper.

FIG. 3 is a cross-sectional view taken along line l-l '.
Wall 8 constituting positioning / pressing portion 3 on three-dimensional wiring board 1
And the distance between the spherical projections 5 are formed to be slightly smaller than the thickness a of the connection portion of the liquid crystal display 10.

FIG. 4 is a sectional view showing a state where the three-dimensional wiring board 1 and the liquid crystal display 10 are connected. The liquid crystal display 10 is slid in the x direction in FIG. 1 to connect to the three-dimensional wiring board 1. The liquid crystal display 10 having a thickness a is connected between the slightly narrower wall 8 and the spherical projection 5. The part 2 is elastically deformed. Since the connecting portion 2 is formed into a tongue-shaped piece by the cutout 4 (see FIG. 1), the connecting portion 2 is deformed into a spring shape. The upper conductive pattern 11 is press-connected.

Therefore, the three-dimensional wiring board 1 and the liquid crystal display 10
In this connection, a contact pressure is generated by the pressure due to the elastic deformation, and the electrical connection is made stable and reliable. The liquid crystal display 10 hits the wall 9 of the three-dimensional wiring board 1 and is positioned in the x direction.

[Second Embodiment] FIG. 5 is a top view showing a second embodiment of the present invention. Reference numeral 21 denotes a three-dimensional wiring substrate, and a connection portion 22, a positioning / pressing portion 23, and a spherical projection 25 are integrally formed by injection molding of plastic, which is an insulating material, as in the first embodiment to form a connection portion. are doing. Further, similarly to the first embodiment, the spherical projection 2
5 and the lead pattern 26 are formed with conductive patterns. The difference from the first embodiment is that the three-dimensional wiring board 21
Is that a fixing portion for fixing a connection with another conductive pattern is integrally formed with the connecting portion. The circuit board 30 connected to this has a conductive pattern row 31 formed on the back surface of the paper. Further, a pair of notches 32 are formed near the connection portion.

FIG. 6 is a sectional view taken along line MM ′ of the connecting portion.
The state where the three-dimensional wiring board 21 and the circuit board 30 are connected is shown. As in the first embodiment, the distance between the wall 28 and the spherical projection 25 is slightly smaller than the thickness of the circuit board.
The first connection portion 22 is elastically deformed, and the conductive patterns 25 and 31 of the two substrates 21 and 30 are stably and reliably connected by the restoring force.

FIG. 7 is a sectional view taken along the line nn 'of the connecting portion.
A fixing protrusion 40 is integrally formed as a fixing portion at an end of the positioning / pressing portion 23. The fixing protrusion 40 fits into the notch 32 on the circuit board 30 when the two substrates 21 and 30 are connected. Is formed. As a result, not only the positioning in the x direction is achieved, but also the two substrates 21 and 30 are prevented from coming off, and are mechanically stably fixed. Therefore, the positioning / pressing portion 23 including the projection 40 also functions as a mechanical fixing portion of the connection, and the connection structure is electrically and mechanically complete.

[0019]

As described above, according to the present invention as set forth in claims 1 to 4, stable operation can be achieved by using only a three-dimensional wiring substrate and a substrate having another conductive pattern without using other components. And a reliable electrical connection is made possible.

According to the fifth aspect of the present invention, in addition to the above-described effects, stable and reliable connection can be achieved not only electrically but also mechanically without using other parts.

By these functions, in connection between the circuit board and other conductive patterns, the cost is reduced by reducing the number of components, the size of the device is reduced, and the cost can be reduced by improving the workability of assembly.

[Brief description of the drawings]

FIG. 1 is a perspective view of a three-dimensional wiring board according to a first embodiment of the present invention.

FIG. 2 is a top view of the three-dimensional wiring board according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view (before connection) of the three-dimensional wiring board according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view (after connection) of the three-dimensional wiring board according to the first embodiment of the present invention.

FIG. 5 is a top view of a three-dimensional wiring board according to a second embodiment of the present invention.

FIG. 6 is a cross-sectional view (after connection) of a three-dimensional wiring board according to a second embodiment of the present invention.

FIG. 7 is a cross-sectional view (after connection) of a three-dimensional wiring board according to a second embodiment of the present invention.

FIG. 8 is a cross-sectional view showing a connection between a substrate and a liquid crystal display according to a conventional example.

[Explanation of symbols]

 1, 21 Three-dimensional wiring board 2, 22 Connection part 3, 23 Positioning and pressing part 4, 24 Cut part 5, 25 Spherical protrusion 6, 26 Leader pattern 7, 8, 9 Wall part 10 Liquid crystal display 11 Conductive pattern 30 Circuit Substrate 31 Conductive pattern 32 Notch 40 Fixing projection

Claims (5)

[Claims] 1. A three-dimensional wiring board in which a conductive pattern is formed on an injection-molded plastic base material, wherein a three-dimensional wiring board is provided with a connection part for making a stable electric connection with another conductive pattern by the elastic force of the plastic base material. Three-dimensional wiring board. 2. The three-dimensional wiring board according to claim 1, wherein a plurality of cuts are provided to obtain an elastic force at a connection part of the three-dimensional wiring board, and the connection part is a tongue-shaped piece. 3. The three-dimensional structure according to claim 1, wherein a pressing part for generating a pressing force with another conductive pattern is formed integrally with the connection part of the three-dimensional wiring board. Wiring board. 4. The three-dimensional circuit according to claim 1, wherein a positioning part for another conductive pattern is formed integrally with the connection part of the three-dimensional wiring board. Wiring board. 5. The connecting part of the three-dimensional wiring board, wherein a fixing part for fixing a connection with another conductive pattern is integrally formed. The three-dimensional wiring board according to the above.