JPH0220876Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a shielding device used to shield electronic circuits configured on printed circuit boards in various electronic devices, and in particular to portable radio receivers, etc. It is useful for use in electronic devices that are designed to be smaller and thinner, such as.

[Background technology and its problems]

Conventionally, in line with the demand for thinner portable radio receivers, etc., the soldering side of the printed circuit board installed inside the radio receiver, etc. and the inner wall of the cabinet of the radio receiver, etc., have been made extremely thin. It becomes necessary to arrange them closely. When the above-mentioned cabinet and printed circuit board are placed close to each other,
In order to prevent noise from being generated in the circuit on the printed circuit board through the cabinet formed of an insulator, a shield sheet is disposed between the printed circuit board and the inner wall of the cabinet. In particular, in the radio receiver as described above, in the manufacturing process, various adjustments such as variable capacitors arranged on the printed circuit board are required before the printed circuit board and the cabinet are assembled. It is necessary that the sheet be provided in advance on the printed circuit board side.

By the way, in the printed circuit board disposed in the above-mentioned radio receiver, it is necessary to provide electronic components such as integrated circuit components on the soldering surface side which is disposed close to the inner wall of the cabinet. When an electronic component is provided on the soldering surface side in this way, if the electronic component is relatively thick, it will protrude from the soldering surface of the printed circuit board. There is a difficulty in that this electronic component prevents the inner wall of the cabinet from approaching the soldering surface of the printed circuit board. Further, the above-mentioned cabinet needs to be formed to have a thickness greater than a certain level in order to maintain a predetermined strength.

Therefore, as shown in Figure 1, the cabinet 1
A recess 4 sufficient to cover the electronic component 3 is provided on the printed circuit board 2 at a position facing the electronic component 3.
By providing this, the electronic component 3 is housed in the recess 4, and the cabinet 1
The printed circuit board 2 and the inner wall of the cabinet 1 can be brought close to each other while maintaining the strength,
The radio receiver and the like can be made thinner.

However, the shield sheet 5 placed between the cabinet 1 and the printed circuit board 2 is
The insulating film 7 is attached to one side of the conductive metal foil 6, that is, the side facing the printed circuit board 2, and its flexibility is limited.
It is difficult to freely deform the recess 4 and the electronic component 3 according to their shapes. Therefore, in order to place the inner wall of the cabinet 1 and the printed circuit board 2 close to each other, it is necessary to make the recess 4 extremely large relative to the electronic component 3, which reduces the strength of the cabinet 1. The disadvantage is that it becomes smaller. Further, when the shield sheet 5 is inserted between the recess 4 and the electronic component 3 and is forcibly bent, tension is applied to the shield sheet 5 and the shield sheet 5 is grounded. a soldering portion 8 that connects the conductive metal foil 6 to the circuit of the printed circuit board 2;
There is a risk that the radio receiver 8 may be damaged due to the load, and this has the drawback that stabilization of the quality of the radio receiver is hindered.

[Purpose of invention]

In view of the above-mentioned circumstances, the present invention has been developed to make electronic equipment smaller and thinner while maintaining the specified strength of insulators such as cabinets, and without adding any burden to the shield sheet. The purpose is to provide a highly durable shield device at low cost.

[Summary of the idea]

That is, in order to achieve the above-mentioned object, the present invention covers the parts attached to the printed circuit board with a flexible shield sheet, and also covers the parts of the insulator disposed on the parts facing the parts. An opening or a recess is provided, and a slit is provided in a part of the shield sheet where the component faces the opening or the recess.

〔Example〕

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

In this embodiment, an electronic device equipped with a shielding device according to the present invention is constructed by connecting a pair of cabinet halves 9 and 10 to each other to form an insulating cabinet 11, as shown in FIG. A tape recorder and a radio receiver are provided in the cabinet 11, and the tape recorder is configured as a portable tape recorder with a radio receiver. The tape cassette used in the tape recorder is stored and mounted in a cassette holder section 12 provided on one of the cabinet halves 9, and the tape cassette used in the tape recorder and the radio receiver circuit are provided. A printed circuit board 13 is provided on the other cabinet half 10. This printed circuit board 13 is housed in the other cabinet half 10 with its soldering surface 13a facing the bottom inner wall of the other cabinet half 10 as shown in FIG. As shown in FIG. 2, the cabinet half 10 is arranged in close contact with the inner wall of the cabinet half 10. On the soldering surface 13a of the printed circuit board 13 is an electronic component 1 such as an integrated circuit component having a substantially rectangular planar shape constituting the circuit of the radio receiver.
4 and this electronic component 14, various extremely small chip components (not shown) are mounted.

A shield sheet 15 is disposed on the soldering surface 13a of the printed circuit board 13 so as to cover a portion where the circuit of the radio receiver is disposed. This shield sheet 15 is arranged on a conductive metal foil 17 that is grounded to the printed circuit board 13 at soldered parts 16, 16, and on the surface of the conductive metal foil 17 that faces the printed circuit board 13. It is formed by pasting an insulating film 18 made of polyester or the like, has enough flexibility to be elastically bent, and is interposed between the cabinet half 10 and the printed circuit board 13. The printed circuit board 13 is electrically shielded. A slit 19 is formed in the shield sheet 15 so as to correspond to the electronic component 14 attached to the printed circuit board 13. The slits 19 are cut into the shield sheet 15 in a U-shape along three adjacent sides of the rectangular electronic component 14. and,
The tongue piece 20 formed on the shield sheet 15 by such a slit 19 is attached to the electronic component 1.
According to the amount of protrusion of the shield sheet 4 , the shield sheet 15 is deformed independently from other parts of the shield sheet 15 to cover the upper surface of the electronic component 14 . The upper surface of the electronic component 14 and the tongue piece 20 of the shield sheet 15 are adhered with double-sided adhesive tape or the like to prevent damage during assembly or adjustment. It is bonded to the upper surface of the electronic component 14, leaving enough room for it to flex freely when a load is applied to the base end. Further, the edge of the shield sheet 15 where the slit 19 is cut is reliably insulated by the insulating film.

Further, the inner wall of the cabinet half 10 facing the electronic component 14 has a recess 21 for accommodating the upper part of the electronic component 14 and for bringing the cabinet half 10 and the printed circuit board 13 into close contact. is formed. The recess 21 is formed into a substantially rectangular shape that is sufficient to cover the electronic component 14, and when the cabinet half 10 and the printed circuit board 13 are brought close to each other, the electronic component 14 is overlapped with the electronic component 14. 14 and the tongue piece 20 of the shield sheet 15, and furthermore, the upper surface of the electronic component 14 is placed inside the shield sheet 1.
The depth is such that it does not come into pressure contact with the bottom surface of the recess 21 via the tongue piece 20 of No. 5.

The portions of the cabinet half 10 other than the recess 21 are formed thickly so that the cabinet 10 as a whole can maintain sufficient strength.

In addition, a shield plate (not shown) is attached to the inner wall of the cabinet half 10, which faces the portion of the printed circuit board 13 where the circuit of the tape recorder is arranged, and serves as a shield for the circuit corresponding to the tape recorder. I'm starting to do it.

Therefore, when the printed circuit board 13 of an electronic device having the shield device configured as described above is assembled to the cabinet half 10, the shape of the electronic component 14 and the shape of the electronic component 14 are adjusted. The tongue piece 20 of the shield sheet 15 formed by the U-shaped slit 19 is accommodated in the recess 21. At this time, only the proximal end of the tongue piece 20 is pressed against the peripheral edge of the recess 21 and receives a pressing load, and this proximal end is bent to curve in one direction. 13 is the above cabinet half 1
It is assembled to 0.

As described above, according to the shield device of this embodiment, when assembling the printed circuit board 13 and the cabinet half 10, the slits 19 are formed in the shield sheet 15, and the easily deformable tongue pieces 20 are formed. Because of this, even when the printed circuit board 13 is placed in close contact with the cabinet half 10, the upper part of the electronic component 14 protruding from the printed circuit board 13 and the shield sheet 15 disposed there will be connected to the cabinet half 10. It is easily accommodated in the recess 21 provided in the net half 10. Therefore,
The conductive metal foil 17 and the printed circuit board 1 are used to ground the shield sheet 15 without applying an excessive load to the shield sheet 15.
Therefore, the soldered portion 16 with 3 will not be damaged due to stress.

Further, since there is no need to enlarge the shape of the recess 21, the strength of the cabinet half 10 is not impaired. Therefore, while maintaining the overall strength of the cabinet 11,
By arranging the printed circuit board 13 close to the cabinet half 10, it is possible to reduce the thickness of the electronic device.

Although the present invention has been specifically explained above based on one embodiment, the present invention is not limited to the above-mentioned embodiment, and various modifications and applications can be made based on the technical idea of the present invention. For example, the cabinet 1 facing the printed circuit board 13 is
1, but may be an insulator such as a chassis in the electronic device, and such an insulator may have an opening instead of the recess 21. Further, the slit 19 is not limited to the U-shape as described above, and the slit 19 is formed between the recess 21 and the electronic component 14.
An H-shaped slit may be formed in the portion facing the printed circuit board 13, or a single-letter slit may be formed depending on the shape of the parts arranged on the printed circuit board 13. In addition, in the case of shielding a circuit for a tape recorder as described above, the recess 21
A shield sheet 15 with the slits 19 formed thereon is arranged in advance on the inner wall of the cabinet 11, and when the printed circuit board 13 and the cabinet 11 are assembled, the printed circuit board 13 is protected by the shield sheet 15. The printed circuit board 13 may be shielded by being covered.

[Effect of idea]

As is clear from the description of the embodiments described above, according to the present invention, since a slit is formed in the shield sheet that covers the printed circuit board, it is easy to insert the components on the printed circuit board into the recess or opening provided in the insulator. can be stored in. Therefore, it is not necessary to form the shape of this recess or opening extremely large with respect to the above-mentioned component, and furthermore, the insulator in the part other than this recess or opening can be formed thickly, so that the above-mentioned insulation It is possible to provide the printed circuit board and the insulator close to each other while maintaining the strength of the body.

In addition, since no excessive load is applied to the shield sheet placed between the insulator and the printed circuit board, the soldered part for grounding the shield sheet will not be damaged, and this shield device can It becomes highly durable.

Furthermore, since this shield device is obtained by forming slits in the shield sheet, it is inexpensive and does not increase the cost of electronic equipment.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the main parts of an electronic device showing an example of a printed circuit board covered with a shield sheet, Figure 2
The figure is an external perspective view showing an electronic device to which the present invention is applied, Figure 3 is a schematic perspective view showing a printed circuit board covered with a shield sheet of the shield device according to the present invention, and Figure 4 is the shield device described above. FIG. 2 is a schematic cross-sectional view of the main parts of the electronic device, showing a state in which a printed circuit board covered with a shield sheet is assembled into a cabinet. 11...cabinet, 13...printed circuit board, 14...electronic component, 15...shield sheet, 19...slit, 21...recess.

Claims (1)

[Scope of utility model registration request] The components attached to the printed circuit board are covered with a flexible shield sheet, and an opening or a recess is provided in a portion of the insulator disposed on the component that faces the component, and the shield sheet is covered with a flexible shield sheet. A shield device comprising a slit provided in a part of the part where the component faces the opening or recess.