JPH0946079A - Shielding in electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify assembling and improve shielding effect, by arranging a shield cover on a board fixed to the case of an electronic apparatus, arranging earth under a power module, and covering the board with a shield case covering its three directions. SOLUTION: A board 2 is arranged on a case 1 made of aluminum die casting. On the board 2, an earth board 3 is previously fixed to an earth line. A power module 4 is mounted on the earth board 3, and covered with a shield case 5. Pawls 5a, 5b are brought into contact with the earth plate 3, and electric continuity is ensured. A shield cover 6 is fixed on the board 2, and electrically connected with the case 1. The board 2, the earth plate 3, and the shield case 5 make electric continuity, and double shield structure is consituted. Thereby excellent shielding effect can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield structure for an electronic device such as a communication device.

[0002]

2. Description of the Related Art Generally, electronic devices such as communication devices, particularly 1-2.
In a portable communication device that generates a high frequency such as GHz, a substrate and a power module (final stage amplifier) mounted on the substrate
The shield structure of is important. With the conventional seal structure,
The power module is surrounded by two sheet metal processed shield plates and screwed, and the board on which the power module is mounted is placed in an aluminum die-cast case, and screwed tightly to the case to improve heat dissipation. Further, a shield cover (made of aluminum die cast) is placed from above, and further fixed by screws in order to establish continuity with the above-mentioned shield plate and the like.

[0003]

However, in the above-mentioned conventional shield structure, since the shield members are all screwed, it is necessary to tap each shield member and the number of assembling steps is increased. As described above, conventionally, there is a drawback that a large number of man-hours and a large number of parts subjected to special processing (screw tap processing) are required in order to reliably achieve the shield effect. SUMMARY OF THE INVENTION It is an object of the present invention to provide a shield structure for an electronic device which solves the above-mentioned conventional drawbacks and is easy to assemble and has a good shield effect.

[0004]

In a shield structure for an electronic device according to the present invention, a shield cover is arranged on a substrate attached to a case of the electronic device, and a ground plate is provided under the power module on the substrate. It is characterized in that it is arranged and a shield case covering three sides is covered on the power module. Further, in the above-mentioned shield structure, a plurality of tabs at the lower end of the shield case are provided, the tabs are attached to the power module, and the tabs are in contact with the ground plate. Further, in the above-mentioned shield structure, at least one leaf spring is provided on the upper part of the shield case, and the leaf spring is configured to contact the shield cover.

[0005]

The power module on the board is first shielded by the grounding plate arranged below it and the shield case that covers the power module, and the case to which the board is attached, and the shield cover arranged on the board. Since it is shielded by and double shielded, a good shielding effect can be obtained. Further, a plurality of tabs are provided at the lower end of the shield case, the tabs contact the ground plate when the shield case is attached, and at least one leaf spring is provided on the upper part of the shield case, and the leaf springs contact the shield cover. With this configuration, the assembly is easy, the man-hours are reduced, and the cost is reduced.

[0006]

1 shows an embodiment of a shield structure in an electronic device according to the present invention, (A) is an exploded perspective view, (B) is a perspective view of a back surface of a shield cover, FIG.
The case where the present invention is applied to a dual band type portable radio device is shown. In FIG. 1, 1 is a case made of die-cast aluminum, 2 is a board on which electronic components are mounted, 3 is a ground plate soldered to the board 2, 4 is a power module mounted on the board 3, and 5 is a power module. A shield case made of sheet metal or the like for shielding the power module 4 and a shield cover 6 made of aluminum die cast or the like. The case 1 has ribs 1a, 1b, 1c for board conduction that come into contact with the ground line of the board 2.
, A screw boss 1d that also serves as a board continuity, a power module mounting screw hole 1e, and a shield cover mounting screw hole 1f
Are integrally formed. The board 2 is formed with a ground plate mounting hole 2a and a hole 2b through which a board fixing screw penetrates. Holes 3b through which the screws for fixing the ground plate penetrate are formed near both ends of the ground plate 3. Power module 4
At both ends, a recess 4a through which a fixing screw passes is formed. The shield case 5 is formed into a shape that surrounds the three sides by sheet metal processing, and the tabs 5a and 5b are formed at the four corners of the lower end.
Two leaf springs 5c are formed in the upper part by cutting and raising. The shield cover 6 has a board conduction rib 6a that comes into contact with the ground line of the board 2, a screw boss 6b that also serves as a board conduction, and a screw boss 6c for fixing to the case 1.
And a screw boss 6d to which a screw for fixing the power module is attached is integrally formed.

When the power module 4 is mounted on the board 2, the ground plate 3 is inserted in advance, and the legs 3a of the ground plate 3 are inserted into the holes 2a formed in the board 2 at several places, and soldered to the ground line on the back surface of the board 2. Attach and attach. Next, the power module 4 is mounted on the ground plate 3, and the power module 4 is covered with the shield case 5. The shield case 5 can be easily attached by the method described in FIGS. First, bring the shield case 5 onto the power module 4 as shown in FIG.
As shown in FIG. 3, the claw 5a on one side of the shield case 5 is attached to the lower edge of the power module 4, and then the claw 5b on the other side is attached to the lower edge of the power module 4 as shown in FIG. The claws 5a and 5b of the shield case 5 after attachment come into contact with the ground plate 3 and become electrically conductive.

When the substrate 2 on which the power module 4 is mounted is placed on the case 1, the above-mentioned ground plate 3 increases the degree of adhesion between the power module 4 and the case 1 and improves electrical and thermal conduction, and the earth. The shield property of the power module is improved by the plate 3 and the shield case 5, which contributes to the electrical performance of the portable wireless device. Next, attach the shield cover 6 on the substrate 2 placed in the case 1,
When fixed with screws, the substrate 2 is electrically connected to the case 1 on the surface of the case 1 side by several ribs 1a provided on the case 1, and the shield cover 6 is the screw boss 6a of the shield cover 2.
By conducting the ribs 6b at several places, the substrate 1 is covered on both the front and back sides with a strong shield member. Further, the shield case 5 covering the power module 4 is also electrically connected by the leaf spring 5b provided on the upper part of the shield case 5. Therefore, all of the shield members (the case 1, the substrate 2, the ground plate 3, the shield case 5, and the shield cover 6) are electrically conducted to form a double shield structure, so that a very good shield effect can be obtained. .

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the above embodiments, the dual band type portable wireless device has been described, but the present invention can also be applied to a single band type portable wireless device and other electronic devices.

[0010]

According to the shield structure of the electronic device of the present invention, the following effects can be obtained. (1) The double shield structure provides a good shielding effect. (2) Since one-touch mounting can be performed without using screws, the assembly is very easy and the man-hour cost can be reduced. (3) The number of taps for screws of each component is reduced, and the cost is reduced. (4) In addition to the electric shield effect, the heat dissipation effect is improved.

[Brief description of drawings]

1A and 1B show an embodiment of a shield structure in an electronic device according to the present invention, FIG. 1A is an exploded perspective view, and FIG. 1B is a perspective view of a back surface of a shield cover, which is applied to a dual-band portable wireless device The case is shown.

FIG. 2 is a diagram illustrating a method of attaching the shield case in FIG.

FIG. 3 is a diagram illustrating a method of attaching the shield case in FIG.

FIG. 4 is a diagram illustrating a method of attaching the shield case in FIG.

[Explanation of symbols]

 1 case 2 board 3 ground plate 4 power module 5 shield case 6 shield cover

Claims (3)

[Claims] 1. A shield cover is arranged on a substrate attached to a case of an electronic device, a ground plate is arranged under the power module on the substrate, and a shield case covering three sides is covered on the power module. A shield structure for electronic devices. 2. The shield structure according to claim 1, wherein
A shield structure in an electronic device, wherein a plurality of tabs at a lower end of a shield case are provided, the tabs are attached to a power module, and the tabs are in contact with the ground plate. 3. The shield structure according to claim 1, wherein:
A shield structure in an electronic device, wherein at least one leaf spring is provided on an upper portion of a shield case, and the leaf spring contacts the shield cover.