JPS63156398A - Printed wiring board unit structure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Outline: A plurality of printed boards are surrounded by a conductive chassis, leaving only the front side. A plurality of front plates having protrusions formed on the inner surface are disposed on the front side of the printed wiring board 1, and a plurality of conductive electromagnetic shielding plates having spring properties are disposed inside the front plates. By fastening the front plate to the chassis by the fastening means, the protrusion provided on the front plate presses and deforms the conductive electromagnetic shield plate, so that the edges of adjacent conductive electromagnetic shield plates are brought into contact with each other. This makes it possible to achieve [i-shielding] of the printed wiring board unit.

INDUSTRIAL APPLICATION FIELD The present invention relates to a printed wiring board (L-knit structure) on which a plurality of printed boards (electronic circuit packages) are mounted, and in particular to a printed wiring board unit structure with electromagnetic shielding measures of 130"g.

An electronic circuit package is an IC on which an electronic circuit is formed.
In the field of computers and communication equipment, such electronic circuit packages are connected to one printed wiring board (backboard) via multiple connectors.
A printed wiring board unit is constructed by connecting the V1 to the V1, simplifying and economical design and improving maintenance convenience.

Computers and communication devices that use this type of printed wiring board unit structure have become faster and more dense in recent years, and effective electromagnetic shielding measures are required as a result, and regulations on electromagnetic noise are becoming stricter every year. There is a tendency to Therefore, there is a need for a printed wiring board unit structure that does not emit electromagnetic waves to the outside of the device.

BACKGROUND ART FIG. 3 shows a schematic diagram of a conventional printed wiring board unit structure, and an electronic circuit package 10 in which a plurality of electronic circuits are mounted on a printed wiring board has a
A plurality of them are connected to the back printed wiring board 14 via the wiring board 14 to form a printed wiring board unit. Such a printed wiring board unit is surrounded by a V-shield 16 made of metal such as aluminum except for its front side, and a plurality of front plates 18 are arranged on the front side, and mounting screws, etc. The front plate 18 is fastened to the chassis 16 by the fastening means shown in FIG. The front plate 18 is generally formed by resin molding in order to reduce cost, and there is a gap between the front plate and the adjacent front plate.

Problems to be Solved by the Invention However, in the conventional printed wiring board unit structure as shown in FIG. 3, since the front plate 18 is formed by resin molding, no electromagnetic shielding measures are taken. Even if you try to take electromagnetic shielding measures by gluing a conductor or applying conductive paint to the inner surface of the front panel, there will be a gap between adjacent front panels, so there will be no leakage from this gap. ``There was a problem that electromagnetic waves leaked and complete electromagnetic shielding measures were impossible.

The present invention has been made in view of these points, and an object thereof is to provide a printed wiring board unit structure that has a simple configuration and provides effective electromagnetic shielding measures.

Means for Solving the Problems A plurality of electronic circuit packages 10 are connected to a printed wiring board 14 via connectors 12, and the periphery of the electronic circuit packages 10, except for the front side, is surrounded by a conductive sheet 16. A plurality of stop plates 18 having protrusions 20 formed on their inner surfaces are arranged on the front side, and a plurality of conductive electromagnetic shield plates 22 having spring properties are arranged inside the iE face plate 18.

When the stop plate 18 is fastened to the chassis 16 by the fastening means, the protrusion 20 provided on the front plate 18 presses and deforms the conductive electromagnetic shield plate 22, so that the edges of the adjacent electromagnetic shield plates 22 are pressed against each other. In this way, electromagnetic shielding of the C1 printed wiring board unit structure is achieved.

Operation When the front plate 18 is fastened to the chassis 16 by the fastening means, the protrusion 20 provided inside the front plate 18 presses the conductive electromagnetic shield plate 22. Conductive electromagnetic shield plate 22
Since the conductive electromagnetic shielding plates 22 are made of a material having good spring properties, both ends thereof in the width direction are expanded, and the edges of the adjacent conductive electromagnetic shielding plates 22 are pressed together to achieve effective electromagnetic shielding.

Embodiments The present invention will be explained in detail below based on embodiments shown in the drawings.

FIG. 1 shows a schematic configuration diagram of an embodiment of a printed wiring board unit structure according to the present invention. Components that are the same as those of the conventional structure shown in FIG. 3 will be described with the same reference numerals. Nizuru.

An electronic circuit package 10 in which a plurality of electronic circuits such as ICs and LSIs are mounted on a printed wiring board includes a connector 12
It is connected to the rear printed wiring board 14 via the back side printed wiring board 14 to constitute a printed wiring board unit. The printed wiring board 1-sheet configured in this way is made of a metal sheet 16 made of aluminum or the like, except for its front side (front side).
surrounded by. A plurality of front plates 18 are disposed on the front side that is not surrounded by the chassis 16. The front plate 18 is, for example, a resin molded product, and a protrusion 20 is formed on the inner surface thereof over the entire length of the front plate. Reference numeral 22 denotes an electromagnetic shielding plate made of a metal material having spring properties, a conductive resin, or the like, and both ends of the electromagnetic shielding plate in the width direction are slightly curved inward.

FIG. 2 shows an enlarged exploded perspective view of the main parts of the embodiment shown in FIG. A screw hole 16a is formed in the holes 17-16 corresponding to the holes. As described above, S curved portions 22b are formed at both ends of the electromagnetic shielding plate 22 in the width direction.

However, in order to fasten the front plate 18 and the electromagnetic shield plate 22 to the chassis 16, the mounting screws 24 are inserted into the mounting holes 18a and 2.
The front plate 18 and the conductive electromagnetic shield plate 22 are attached to the chassis 16 by passing through the screw holes 16a and tightening them. At this time, since projections 20 are formed on the inner surface of the front plate 18, when the mounting screws 24 are tightened, the electromagnetic shielding plate 22 is pressed by the projections 20 and deforms, and the curved portions 22b provided at both widthwise ends of the electromagnetic shielding plate 22 are deformed. expands. In this way, as shown in FIG. 1, the edges of adjacent electromagnetic shielding plates 22 come into pressure contact with each other, making it possible to form a continuous electromagnetic shield on the front side.

Up)! In this embodiment, the projections 20 are formed on the inner surface of the front plate 18 over the entire length thereof.
The present invention is not limited to this, but also includes embodiments in which the protrusions 20 are formed discontinuously. Furthermore, curved portions 22 are formed at both ends of the electromagnetic shielding plate 22.
It is not limited to b, and may be a bent portion bent at a shallow angle, for example.

Effects of the Invention Since the present invention is configured as detailed above, it is possible to achieve effective electromagnetic shielding, thereby effectively preventing malfunction of internal equipment due to external electromagnetic noise and leakage of electromagnetic waves from internal equipment. It has the effect of being able to

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention, FIG. 2 is an enlarged exploded perspective view of essential parts of the embodiment of FIG. 1, and FIG. 3 is a schematic configuration diagram C of a conventional example. DESCRIPTION OF SYMBOLS 10... Electronic circuit package, 12... Connector, 14... Rear printed wiring board, 16... Chassis, 18... Front plate, 20... Protrusion, 22... Conductive electromagnetic shield Board. , -2/' 182 zm Oi 22: Under the gun is Nuru Doo - Kotomitsu Akira 15 Jime Box 1 Ital Figure 1 1o: Kenchi Kaiku Package゛16: Nunshi 18: Gomen Saisara

Claims (1)

[Claims] A printed wiring board in which a plurality of printed boards (10) are surrounded by a conductive chassis (16), leaving only the front side thereof, and a plurality of front boards (18) are arranged on the front side. In the unit structure, a plurality of conductive electromagnetic shielding plates (22) having spring properties are arranged inside the front plate (18), and protrusions (20) are formed on the inner side of the front plate (18). When the front plate (18) is fastened to the chassis (16) by the fastening means, the protrusion (20) presses and deforms the conductive shield plate (22), so that the adjacent conductive electromagnetic shield plate (22) ) A printed wiring board unit structure characterized in that the edges of the two sides are in contact with each other.