JPH06244584A - Shielding mechanism for printed board - Google Patents

Abstract

PURPOSE:To obtain shielding mechanism capable of simplifying assembly and improving reliability, by making a spring type abutting part abut against a first ground pattern, inserting an engaging part from the mounting surface side of a printed board, and engaging said part with the rear. CONSTITUTION:On the surface of a printed board 1, a ground pattern 3 is formed so as to surround electric/electronic circuit. On the rear, a ground pattern 4 is formed on the whole part of a region corresponding with the mounting region. Electric conduction holes 2 which electrically connect the patterns 3, 4 are arranged at equal intervals. Protruding parts 7 of a case 5 are inserted into electric conduction holes 2a, protruding parts 6 are pressed against the ground pattern 3, and tip parts of the protruding parts 7 are bent. The case 5 is fixed to the printed board 1 in the state that the case is in contact with the ground pattern 3 via the protruding parts 6. Thereby the electric/electronic circuit is enclosed by electric conduction holes 2, 2a, the ground patterns 3, 4, the case 5 and a cover 8, so that electric shielding of the electric/electronic circuit can be ensured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield mechanism for a printed circuit board, and more particularly to an electric shield structure for electrically shielding an electric / electronic circuit mounted on the printed circuit board.

[0002]

2. Description of the Related Art Conventionally, in this type of electric shield structure, as shown in FIG. 4, an electric / electronic circuit (not shown) and an electric / electronic component mounting surface to be electrically shielded are mounted on a printed circuit board 1. The conductive holes 12 are provided in the vicinity of the space below the interval for blocking the radio wave of the frequency to be shielded.

A projection 16 of the case 15 is provided in the through hole 12.
The conductive holes 12 and the protrusions 16 are joined to the ground pattern 14 provided on the back surface of the printed board 11 by the solder 9. The upper surface of the case 15 is covered with a cover 17.

The plate 19 covering the back surface of the printed circuit board 11 corresponding to the surface on which the electric / electronic circuit and the electric / electronic component are mounted is provided with a screw inserted into a mounting hole 13 provided in the outer peripheral portion of the conduction hole 12. Printed circuit board 1 by 20
It is fixed at 1.

By connecting the case 15, the cover 17, the conductive hole 12 of the printed circuit board 11, the ground pattern 14 and the plate 19 with a metal, an electric / electronic circuit and an electric / electronic component on the printed circuit board 11 are formed. Since it is wrapped, the electric shield of electric / electronic circuits and electric / electronic components is secured.

Regarding the method of performing the electric shield from the front surface and the back surface of the printed circuit board 11, in addition to the above method, it is disclosed in the technique disclosed in Japanese Utility Model Publication No. 62-30400 and the Japanese Utility Model Publication No. 63-46900. Technology.

[0007]

In the above-mentioned conventional electric shield structure, in order to improve the electric shield performance between the printed board and the case, the projection of the case fitted into the conductive hole of the printed board and soldered. It is necessary to reduce the distance between them.

However, if the number of the projections is increased by reducing the distance between the projections of the case, it becomes difficult to insert the projections of the case into the conductive holes of the printed circuit board.
Further, it is necessary to solder the entire circumference of the projection of the case to the conduction hole of the printed circuit board, which complicates the assembly and easily causes soldering failure, leading to a decrease in reliability.

On the other hand, in order to bring the entire circumference of the plate into contact with the ground pattern of the printed circuit board, it is necessary to cover the ground pattern so that the solder does not adhere to portions other than the contact area of the case, and the ground pattern plate and It is necessary to keep the contact surface flat.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printed circuit board shield mechanism which solves the above problems, simplifies assembly, and improves reliability.

[0011]

A shield mechanism for a printed circuit board according to the present invention is a shield mechanism for a printed circuit board on which an electric circuit to be electrically shielded is mounted, and the electric circuit is mounted on the mounting surface of the electric circuit on the printed circuit board. A strip-shaped first ground pattern formed so as to surround the circuit, a second ground pattern formed on at least the entire surface of the back surface of the printed circuit board corresponding to the mounting area of the electric circuit, and the periphery of the electric circuit A conductive hole for electrically connecting the first and second ground patterns to each other, a spring-shaped contact portion that contacts the first ground pattern, and a mounting surface of the printed circuit board. A case member that is inserted from the side and that is locked to the back surface of the printed circuit board, and that electrically shields the electric circuit.

Another printed circuit board shield mechanism according to the present invention is a printed circuit board shield mechanism on which an electric circuit to be electrically shielded is mounted, and a mounting area of the electric circuit on a mounting surface of the printed circuit board on which the electric circuit is mounted. And a first ground pattern formed so as to cover the entire area other than the mounting area of the other electric circuit, and a first ground pattern formed on the entire surface of the back surface of the printed circuit board at least corresponding to the mounting area of the electric circuit. A second ground pattern, and a conductive hole provided around the electric circuit for electrically connecting the first and second ground patterns to each other,
The electric circuit is composed of a spring-shaped contact portion that contacts the first ground pattern and a locking portion that is inserted from the mounting surface side of the printed circuit board and locked on the back surface of the printed circuit board. And a case member for electrically shielding.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a perspective view showing an embodiment of the present invention. In these drawings, an electric / electronic circuit (not shown) in which a strip-shaped ground pattern 3 is mounted on the surface of the printed circuit board 1 (not shown) (including electric / electronic components mounted on the printed circuit board 1) ) Is formed to surround.

A ground pattern 4 is formed on the back surface of the printed circuit board 1 over the entire area corresponding to the mounting area of the electric / electronic circuit. The formation area of the ground pattern 4 may be the entire back surface of the printed board 1.

Conducting holes 2 for electrically connecting the ground patterns 3 and 4 to each other are arranged at equal intervals in the band-shaped ground pattern 3, and inside the conducting hole 2, a case 5 is provided. Conductive hole 2a having a shape through which the protrusion 7 can be inserted
Is provided.

The case 5 is provided with a spring-shaped protrusion 6 so as to come into contact with the ground pattern 3, and
A protrusion 7 is provided for inserting the case 5 into the printed circuit board 1 by inserting the case 5 into the conduction hole 2a.

That is, the projecting portion 7 of the case 5 is connected to the through hole 2
By pressing the protrusion 6 against the ground pattern 3 while inserting it into the a, and bending the tip of the protrusion 7 in this state,
The case 5 is fixed to the printed circuit board 1 while being in contact with the ground pattern 3 by the protrusion 6.

When the cover 8 is fitted and covered on the upper surface of the case 5, the cover 8 is covered by the spring portion 8a.
Fixed to. As a result, the conductive holes 2 and 2a of the printed board 1, the strip-shaped ground pattern 3 and the ground pattern 4 on the back surface, the case 5, and the cover 8 are connected by metal.

Therefore, the electric / electronic circuit on the printed circuit board 1 is enclosed by the conductive holes 2 and 2a, the band-shaped ground pattern 3, the ground pattern 4 on the back surface, the case 5 and the cover 8. The shield is secured.

FIG. 3 is a perspective view showing another embodiment of the present invention. In the figure, another embodiment of the present invention is the same as one embodiment of the present invention except that the ground pattern 9 is used for all parts other than the mounting surface of the electric / electronic circuit and the other electric / electronic component 10 on the surface of the printed board 1. The same components are designated by the same reference numerals.

In another embodiment of the present invention, the printed circuit board 1
Conductive holes 2 are arranged at equal intervals around the electric and electronic circuit of
A conduction hole 2a is arranged inside the conduction hole 2. Therefore, the ground pattern 9 is electrically connected to the ground pattern 4 on the back surface of the printed board 1 through the conduction holes 2 and 2a.

As a result, electricity on the printed circuit board 1
The electronic circuit is wrapped with the conduction holes 2 and 2a, the ground pattern 9, the ground pattern 4 on the back surface, the case 5, and the cover 8 to secure the electric shield of the electric / electronic circuit.

In this way, the conductive hole 2a of the printed circuit board 1
Insert the projection 7 of the case 5 into the
By bringing the protrusions 6 of the above into contact with the ground patterns 3 and 9 on the surface of the printed circuit board 1, the electric shield function can be ensured by the above-described processing and the processing of fitting the cover 8 to the case 5, so that the assembly is performed. It can be greatly simplified.

Further, since solder is not used for connecting the printed circuit board 1 and the case 5 to each other by the biasing force of the projecting portion 6 of the case 5 and bending of the projecting portion 7, defective soldering is avoided. In addition, it is possible to make a stable connection by the contact by the urging force of the protrusion 6. Therefore, the assembly can be simplified and the reliability can be improved.

[0026]

As described above, according to the present invention, the band-shaped first ground pattern is formed on the mounting surface of the printed circuit board on which the electric circuit to be electrically shielded is mounted so as to surround the electric circuit, and the printed pattern is formed. A second ground pattern is formed on at least the entire surface of the back surface of the substrate corresponding to the mounting area of the electric circuit, and the first and second ground patterns are electrically connected to each other through a conductive hole to form the electric circuit. Assembling the case member to be electrically shielded with the spring-shaped abutting portion in contact with the first ground pattern and by inserting the locking portion from the mounting surface side of the printed board and locking the back surface. There is an effect that it can be simplified and the reliability can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing an embodiment of the present invention.

FIG. 3 is a perspective view showing another embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a conventional example.

[Explanation of symbols]

 1 Printed Circuit Board 2, 2a Conduction Hole 3 Band-shaped Ground Pattern 4, 9 Ground Pattern 5 Case 6 Spring-shaped Projection 7 Projection 8 Cover 8a Spring Part

Claims (2)

[Claims] 1. A shield mechanism for a printed circuit board on which an electric circuit to be electrically shielded is mounted, the strip-shaped first ground being formed on a surface of the printed circuit board on which the electric circuit is mounted so as to surround the electric circuit. A pattern, a second ground pattern formed on at least the entire surface of the back surface of the printed circuit board corresponding to the mounting area of the electric circuit, and the first and second ground patterns provided around the electric circuit. A conductive hole for electrically connecting to each other, a spring-shaped contact portion that contacts the first ground pattern, and a mounting surface side of the printed circuit board that is inserted and locked to the back surface of the printed circuit board. And a case member that electrically shields the electric circuit. 2. A shield mechanism for a printed circuit board on which an electric circuit to be electrically shielded is mounted, wherein a mounting area of the electric circuit other than a mounting area of the electric circuit and a mounting area of another electric circuit is provided on a mounting surface of the electric circuit of the printed circuit board. A first ground pattern formed so as to cover the entire area, a second ground pattern formed on the entire back surface of the printed circuit board corresponding to at least the mounting area of the electric circuit, and the periphery of the electric circuit A conductive hole for electrically connecting the first and second ground patterns to each other, a spring-shaped contact portion that contacts the first ground pattern, and a mounting surface of the printed circuit board. A case member that is inserted from the side and that is locked to the back surface of the printed circuit board, and that electrically shields the electric circuit. Shield mechanism.