JPH10163669A - Shielding member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shielding member which has excellent operability and is adapted to a target by overlapping a conductive paste for shielding electromagnetic wave on a wave absorber and giving to adhesive property to the conductive paste. SOLUTION: A shielding member has a double structure of a metal and a wave absorber 1 obtained by coating or adhering a conductive paste 19 derived by dispersing metallic particles such as silver powders or copper powders in a resin binder and mixing an adhesive on a wave absorber 1 and forming it in a sheet or tape shape. The shielding member is adhered to the inside of the casing so as to cover the whole or a part of a printed board on which electronic parts as a noise source are mounted by using the adhesive in the conductive paste 19. Consequently, wave leakage can be shielded by the conductive paste 19 and noises occurred from the inside of the device are passed through the wave absorber 1 and attenuated. Thus, an 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 member for suppressing unnecessary electromagnetic waves generated from electronic equipment or suppressing mutual interference in a circuit.

[0002]

2. Description of the Related Art FIG. 20 is a view showing the structure of a conventional shield member described in Japanese Patent Application Laid-Open No. 54-58301. In the figure, 1 is a radio wave absorber and 2 is a metal. The radio wave absorber 1 and the metal 2 are bonded as far as can be estimated from the figure. The above publication also discloses a wave absorber 1 and a metal 2 having a smooth and parallel structure in which no wave occurs.

When the bonded shield member is used for suppressing electromagnetic waves, for example, an adhesive is further applied to the outside of the metal 2, and the shield member is bonded to the target surface. When the shield member having the above configuration is attached to, for example, the inside of the housing, radio waves transmitted to the air from the transmission circuit and the amplification circuit housed in the housing are attenuated by the radio wave absorber of the shield member and further reflected by metal. The applied radio wave is once again attenuated by the radio wave absorber, so that even if the radio wave is re-input to the circuit, the radio wave is not affected.

[0004]

Since the conventional shield member is configured as described above, an adhesive work is required when the shield member is installed in accordance with an object, and it takes extra time.
There was a problem that workability was poor.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has as its object to obtain a shield member which has good workability and is suitable for an object.

[0006]

In a shield member according to the present invention, a conductive paste for shielding electromagnetic waves is superimposed on a radio wave absorber, and the conductive paste has an adhesive property.

[0007] Alternatively, an adhesive is applied to at least one of the radio wave absorber and the electromagnetic wave shielding metal sheet that has a structure in which the radio wave absorber and the electromagnetic wave shielding metal sheet are bonded to each other and is not bonded to each other. did.

Furthermore, the opposite side of the electromagnetic wave shielding metal sheet to the first radio wave absorber bonded to the first radio wave absorber is covered with an insulating sheet or a second radio wave absorber, and is different from the above-mentioned bonding surface of the first radio wave absorber. An adhesive was applied to the surface.

[0009] Furthermore, a structure in which a radio wave absorber and a conductive paste or an electromagnetic wave shielding metal sheet are overlapped, or a structure in which a metal sheet covers an equivalent of an insulating sheet,
The radio wave absorber, one of the conductive paste or the metal sheet, and when covered with an insulating sheet, one of the radio wave absorber and the other sheet is longer than the other, and An adhesive or a conductive adhesive was applied to the portion to be bonded.

Further, the bonded shield member is
It was formed in a tape shape.

Further, a portion corresponding to the radio wave absorber or the insulating sheet is removed, and the removed portion has a structure in which the metal sheet or the conductive paste is exposed.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. An embodiment of the present invention will be described below with reference to the drawings for a shield member having excellent workability during mounting. FIG. 1 is a configuration diagram of a shield member according to the present embodiment, and FIG. 2 is a mounting diagram illustrating an example in which the shield member is mounted on a housing. 1 and 2, 1 is a radio wave absorber, 19 is a conductive paste mixed with an adhesive, 6 is a shield member made of the radio wave absorber 1 and the conductive paste 19, 7 is a printed board, 8 is an electronic component, 9 is a housing. The shield member 6 according to the present invention, as shown in FIG.
Metal particles such as silver powder or copper powder are dispersed in a resin binder in the radio wave absorber 1 and a conductive paste mixed with an adhesive is applied or pasted into a sheet-shaped or tape-shaped metal / It has a two-layer structure of a radio wave absorber.

As shown in FIG. 2, a conductive paste is provided inside the housing 9 so as to cover the whole or a part of the printed circuit board 7 on which the electronic component 8 serving as a noise source is mounted. It is pasted using the adhesive in 19. Therefore, even when used in an electronic device using a non-conductive casing 9 made of plastic or the like, noise generated from inside the device can block radio wave leakage by the conductive paste 19 and pass through the radio wave absorber 1. Therefore, an excellent shielding effect can be obtained.
Further, interference by radio waves reflected by the conductive paste 19 can be prevented by the radio wave absorber 1. Furthermore, since the attachment to the housing 9 or the like is performed in the conductive paste 19, it is very easy.

Embodiment 2 FIG. Similarly, another shield member having improved workability will be described. FIG. 3 is a diagram illustrating a configuration of another shield member. In FIG. 3, 1 is a radio wave absorber, 2 is a metal sheet, 4 is an adhesive, and 6 is a shield member made of these. The shield member 6 shown in FIG.
Uses the metal sheet 2 and the adhesive 4 instead of the conductive paste 19 containing the adhesive described in the above embodiment, and uses the adhesive 4 to attach the shield member 6 to the housing 9. Paste to etc. Therefore, the shield member 6 is not peeled off from the housing 9 or the like, and a highly reliable shield member 6 can be obtained.

Embodiment 3 A shield member having an insulating property on the bonding side to further improve workability and workability will be described. FIG. 4 is a configuration diagram of the shield member described here, and FIG. 5 is a diagram illustrating a usage example in which the shield member of FIG. 4 is attached to an electronic component. In FIGS. 4 and 5, there is an insulating sheet 3 as a new element.
Is an electronic component. In a shield member 6 shown in FIG. 4, one surface of the metal sheet 2 is covered with the insulating sheet 3 and the radio wave absorber 1 is adhered to the other surface using an adhesive 4, and the other surface of the radio wave absorber 1 And an adhesive 4 for sticking to electronic components
Is provided.

As shown in FIG. 5, the shield member 6 is attached to the electronic component 8 using the adhesive 4. Therefore,
Since it can be directly attached to the electronic component 8 as a noise source,
The required minimum shield member 6 can effectively block radio wave leakage and prevent interference with other components and the like. Further, the adhesive to the electronic component 8 or the like is
It is very easy because it is done by.

Another shield member of the present embodiment will be described with reference to the drawings. 6 and 7, 1 is a radio wave absorber, 2 is a metal sheet, 4 is an adhesive, 6 is a shield member,
7 is a printed circuit board, 11 is a signal line, and 12 is a partition plate.

In the shield member 6 shown in FIG. 6, the radio wave absorber 1 is attached to both surfaces of the metal sheet 2 using an adhesive 4,
An adhesive 4 is provided on the other surface of one of the radio wave absorbers 1 (the second radio wave absorber) to be attached to the partition plate 12 or the like. This shield member 6, as shown in FIG.
The adhesive 4 is attached to a partition plate 12 provided between the signal lines 11 wired on the printed circuit board 7.
Therefore, interference between the signal lines 11 can be prevented.
In addition, by arranging not only between lines but also between blocks to be separated such as a digital unit and an analog unit, interference between these blocks can be prevented. Furthermore,
The attachment to the partition plate 12 or the like is very easy because it is performed by the adhesive 4.

Embodiment 4 A shield member according to another embodiment of the present invention will be described with reference to the drawings. FIG. 8 is a configuration diagram of a shield member according to the present embodiment, and FIGS.
FIG. 4 is a diagram showing an example in which the shield member is applied. 8, 9, and 10, 5 is a conductive adhesive, 6 is a shield member, and 13 is a cable. Other elements are
This is the same as the element of the same number in the embodiment. The shield member 6 shown in FIG. 8 is covered with the insulating sheet 3 except one side of one surface of the metal sheet 2, and the radio wave absorber 1 is attached to the other surface using the adhesive 4. At this time, the radio wave absorber 1 is not provided on the back surface opposite to the portion where the metal sheet 2 is not covered with the insulating sheet 3, and the conductive adhesive 5 is provided.

The shield member 6 is wound around a cable 13 disposed inside and outside the electronic device as shown in FIG. At this time, the cable 13 is shielded over the entire circumference by laminating the part of the metal sheet 2 from which the insulating sheet 3 is removed on the back side opposite to the one side with the conductive adhesive 5 provided on one side of the metal sheet 2. Can be. Since the shield member 6 is attached to the cable 13 simply by winding the sheet-shaped or tape-shaped shield member 6 and fixing it with the conductive adhesive 5, even if the connector is already connected, It is not necessary to cut 13 and it can be easily performed. Furthermore, it can be similarly attached not only to the cable 13 having a circular cross section, but also to the flat cable 13 shown in FIG.

Another shield member having the same purpose will be described with reference to the drawings. 11 is a configuration diagram of a shield member described below, FIG. 12 is a diagram illustrating a shape of the shield member, and FIG. 13 is a diagram illustrating an example in which the shield member is applied to cover a cable. In FIGS. 11, 12, and 13, reference numeral 13 denotes a cable. The other elements are the same as the already described elements of the same number. A shield member 6 shown in FIG.
And a shield member 6 in the form of a tape or a stick having the radio wave absorber 1 adhered to the other surface using an adhesive 4. The shield member 6 is formed in a spiral shape as shown in FIG. Things.

This shield member 6 is, as shown in FIG.
It is wrapped around the cable 13 disposed inside and outside the electronic device, absorbs noise generated from the cable 13, can reduce leaked radio waves and prevent interference with other devices and components. Since the shield member 6 is attached to the cable 13 simply by winding the sheet-shaped or tape-shaped shield member 6 formed in a spiral shape, the cable 13 is cut even when the connector is already connected. It can be easily performed without the necessity of performing, and can be detached.

Still another shield member having the same purpose will be described with reference to the drawings. FIG. 14 is a configuration diagram of a shield member described below, and FIG. 15 is a diagram illustrating an application example of the shield member. 14 and 15, reference numeral 14 denotes a connector;
Reference numeral 15 denotes a land for GND. The other elements are the same as the elements of the same number already described. The shield member 6 shown in FIG.
And the radio wave absorber 1 is attached to the other surface using an adhesive 4. At this time, the radio wave absorber 1 is not provided on both sides of the metal sheet 2 but the conductive adhesive 5 is provided.

This shield member 6, as shown in FIG.
It is attached so as to cover the connector 14 mounted on the printed circuit board 7 or the like, and is connected to the GND land 15 provided on the printed circuit board 7 around the connector 14 using the conductive adhesive 5. Accordingly, the connector 14 is covered around the metal sheet 2 and the GND in the printed circuit board 7 by the GND, and the radio wave absorber 1 is arranged between the connector 14 which is a noise generating source and the surrounding metal. Therefore, radio waves leaking from the connector 14 can be reduced, and interference with other devices and components can be prevented. In addition,
Since the connection between the GND land 15 and the metal sheet 2 is performed by the conductive adhesive 5, it is very easy. The adhesive 4 for attaching the shield member 6 to the connector 14 may be added to the radio wave absorber 1 as needed.

Embodiment 5 FIG. A shield member according to another embodiment of the present invention will be described with reference to the drawings. FIG. 16 is a configuration diagram of a shield member according to the present embodiment, and FIG.
It is a figure showing an example of application of the shield member. 16 and 17, 6 is a shield member, 10 is a metal frame, 16 is a GND connection terminal, and 17 is a gasket. The other elements are the same as the elements of the same number already described. The shield member 6 shown in FIG. 16 is different from the shield member 6 described in the above embodiment in that a terminal 16 for removing a part of the insulating sheet 3 provided on one side of the metal sheet 2 and connecting to a ground of an electronic device is provided. It is what it was.

The shield member 6 is, as shown in FIG.
The electronic component 8 is attached to the electronic component 8 mounted on the printed circuit board 7 using an adhesive 4, and the metal frame 10 of the electronic device and the GND connection terminal 16 are electrically connected using a gasket 17 or the like. Therefore, the metal frame 10 and the metal sheet 2 have the same potential, and a better shielding effect can be realized. Although the GND connection terminal 16 provided on the shield member 6 shown in the embodiment is one, a more excellent shielding effect can be obtained by providing a plurality of terminals.

Another shield member having the same purpose will be described with reference to the drawings. FIG. 18 is a configuration diagram of a shield member described below, and FIG. 19 is a diagram illustrating an application example of the shield member. 18 and 19, reference numeral 18 denotes a metal screw. The other elements are the same as the elements of the same number already described. The shield member 6 shown in FIG. 18 is the same as the shield member 6 described in the above embodiment, except that the metal sheet 2 is expanded and the terminals 16 are connected to the ground of the electronic device.
It is what it was.

This shield member 6 is, as shown in FIG.
An adhesive 4 is attached to the inside of the housing 9 so as to cover the whole or a part of the metal frame 10 covered with an electronic circuit or the like serving as a noise source, and a metal screw 18 or
The metal frame 10 and the GND connection terminal 16 are electrically connected using a gasket 17 or the like. Therefore,
The metal frame 10 and the metal sheet 2 have the same potential, and a better shielding effect can be realized. Although the number of the GND connection terminals 16 provided on the shield member 6 shown in the embodiment is four, the number of the terminals is not limited.
In the case of an electronic device that does not use the metal frame 10, the GND connection terminal 16 and the GND of the printed circuit board are used.
May be connected.

The components of the radio wave absorber 1 will be described. The shield member 6 according to the present invention is different from the shield member 6 described in the above embodiment in that one or both of ferrite powder and carbon powder are dispersed in a synthetic resin binder or a rubber binder as the radio wave absorber 1. The compounded material is used. By using such a radio wave absorber 1, a shield member 6 which is thin and whose shape can be easily changed by bending or cutting can be obtained.

[0030]

According to the present invention, since the present invention is configured as described above, radio waves leaking to the outside are shielded, and interference due to reflected radio waves is prevented by a radio wave absorber. There is an effect that it can be easily attached to a substrate and has excellent workability.

Further, since it can be directly attached to the electronic component which is a noise source, it is possible to effectively block radio wave leakage with a minimum necessary shield member and to prevent interference with other components. There is. Attachment of the shield member to the cable has an effect that it is not necessary to cut the cable even when the connector is already connected, and it can be easily performed. Further, by setting the metal frame of the electronic device and the metal sheet in the shield member to the same potential, an excellent shielding effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional configuration diagram of a shield member according to Embodiment 1 of the present invention.

FIG. 2 is a diagram showing an example in which the shield member of FIG. 1 is attached.

FIG. 3 is a sectional configuration diagram of a shield member according to Embodiment 2 of the present invention.

FIG. 4 is a sectional configuration diagram of a shield member according to a third embodiment of the present invention.

FIG. 5 is a view showing an example in which the shield member of FIG. 4 is attached.

FIG. 6 is a sectional configuration diagram of another shield member according to the third embodiment.

FIG. 7 is a view showing an example in which the shield member of FIG. 6 is attached.

FIG. 8 is a sectional configuration diagram of a shield member according to a fourth embodiment of the present invention.

FIG. 9 is a diagram showing an example in which the shield member of FIG. 8 is attached.

FIG. 10 is a view showing an example in which the shield member of FIG. 8 is attached.

FIG. 11 is a sectional configuration diagram of another shield member according to the fourth embodiment.

FIG. 12 is a view showing a shape of a shield member of FIG. 11;

FIG. 13 is a view showing an example in which the shield member of FIG. 11 is attached.

FIG. 14 is a sectional configuration diagram of another shield member according to the fourth embodiment.

FIG. 15 is a perspective view showing an example in which the shield member of FIG. 14 is attached.

FIG. 16 is a diagram illustrating a configuration of a shield member according to a fifth embodiment of the present invention.

17 is a diagram showing an example in which the shield member of FIG. 16 is attached.

FIG. 18 is a diagram illustrating a configuration of another shield member according to the fifth embodiment.

FIG. 19 is a view showing an example in which the shield member of FIG. 18 is attached.

FIG. 20 is a cross-sectional configuration diagram of a conventional shield member.

[Explanation of symbols]

1 radio wave absorber, 2 metal sheet, 3 insulating sheet, 4
Adhesive, 5 conductive adhesive, 6 shielding member, 7
Printed circuit board, 8 electronic components, 9 housing, 10 metal frame, 11 signal line, 12 partition, 13 cable,
14 connectors, 15 lands for GND, 16 GND
Connection terminal, 17 gasket, 18 metal screw, 19
Conductive paste, 20 hybrid IC, 21 resin mold.

Continued on the front page (72) Inventor Toshio Otake 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Within Mitsubishi Electric Corporation (72) Inventor Katsumi Toyama 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric (72) Inventor Shuji Urasaki 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation

Claims (6)

[Claims] 1. A shielding member, wherein a conductive paste for shielding electromagnetic waves is superimposed on a radio wave absorber, and said conductive paste has an adhesive property. 2. A structure in which a radio wave absorber and an electromagnetic wave shielding metal sheet are bonded together, and an adhesive is applied to at least one of the radio wave absorber and the electromagnetic wave shielding metal sheet that are not bonded to each other. A shield member characterized by the following. 3. The opposite side of the electromagnetic wave shielding metal sheet to the first radio wave absorber bonded to the first radio wave absorber is covered with an insulating sheet or a second radio wave absorber, and the surface of the first radio wave absorber is different from the bonding surface. 3. The shield member according to claim 2, wherein an adhesive is applied to the shield member. 4. A structure in which a radio wave absorber and a conductive paste or an electromagnetic wave shielding metal sheet are overlapped, or a structure in which an equivalent of an insulating sheet is covered on the metal sheet, wherein the radio wave absorber and the conductive paste Or one of the metal sheets and, if covered with an insulating sheet, one of the radio wave absorber and the other sheet is longer than the other, and the long part is provided with an adhesive or The shield member according to any one of claims 1 to 3, wherein a conductive adhesive is applied. 5. The shield member according to claim 1, wherein the bonded shield member is formed in a tape shape. 6. The structure according to claim 1, wherein a portion corresponding to the radio wave absorber or the insulating sheet is removed, and the removed portion has a structure in which the metal sheet or the conductive paste is exposed.
A shield member according to claim 3.