JPH08102593A - Electromagnetic shield device for electronic equipment - Google Patents

Abstract

PURPOSE: To provide an electromagnetic shield device which can surely shield electronic equipment and can reduce the size of the equipment as a whole by providing a plurality of conductive elastic members which are mounted on a grounded surface provided on a second printed board by soldering in corresponding to connecting groove sections formed in a shielding frame member. CONSTITUTION: An electromagnetic shield device for electronic equipment is constituted of a first printed board 4 on which electronic element groups 9 are arranged, shield frame member 5 which has the shape of a rectangular pipe and a plurality of connecting groove sections 7 in its opened end section and is put on the board 4 so that the member 5 can surround the electronic element groups 9, second printed board 6 which has a grounded surface, and a plurality of conductive elastic members 8 which are mounted on the second printed board 6 in corresponding to the groove sections 7 of the shield frame member 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is intended to prevent the adverse effect of electromagnetic waves on an electronic element group constituting an electronic circuit of an electronic device such as a television tuner or a mobile phone.
The present invention relates to an electromagnetic shield device for an electronic device that surrounds an electronic element group and shields electromagnetic waves, and particularly to an electromagnetic shield device for an electronic device that is suitable for use in a small portable wireless device such as a mobile phone.

[0002]

2. Description of the Related Art Electronic devices such as radios and computers are
Electromagnetic waves are often generated from a part of an electronic circuit that constitutes this electronic device. In this electronic device, an electromagnetic wave generated from a part of an electronic circuit causes electromagnetic radiation and electromagnetic interference in another electronic circuit, which adversely affects the other electronic circuit.

Therefore, in an electronic device, a shield member made of a conductive material is provided between two parts of the electronic circuit in order to suppress the interference of electromagnetic waves generated from the part of the electronic circuit with other electronic circuits as much as possible. It is inserted and electromagnetically shielded.

The conventional electromagnetic shield device has two electronic circuits.
Between the parts, a wall or a shape that completely covers and surrounds one part is formed. Further, the electromagnetic shield device is arranged so as to surround an electronic circuit that generates an electromagnetic wave or surrounds an electronic circuit that is affected by the electromagnetic wave.

In the electromagnetic shield device, a shield member generally formed of a copper plate is soldered to a printed circuit board provided with an electronic circuit for electromagnetic shielding. However, in this electromagnetic shield device, it is difficult to remove the shield member from the printed board when the electronic circuit needs to be serviced. Therefore, the shield member
An opening is provided, and a lid that closes the opening is detachably attached.

FIG. 9 shows a conventional electromagnetic shield device 50.
And FIG. 10 will be described. The electromagnetic shield device 50 includes a first printed circuit board 51 provided with an electronic circuit.
A shield member 53 provided on the first printed board 51, a lid 54 attached to the shield member 53, and a second printed board 56 superposed on the lid 54. .

A printed circuit 51A is provided on the main surface of the first printed circuit board 51, and a plurality of electronic element groups 52 constituting an electronic circuit are arranged on the printed circuit 51A. The shield member 53 is formed of a conductive material in a substantially rectangular tubular shape, and the first printed circuit board 5
1 in a state of enclosing the electronic element group 52 arranged in
The printed circuit board 51 is soldered and arranged.

The lid 54 is formed of a conductive material in a substantially box-like shape with a bottom, and a plurality of substantially S-shaped engaging pieces 55 are integrally provided at the ends of opposing side surfaces. .
The lid 54 is attached to the outer peripheral portion of the side surface of the shield member 53 by the elastic force of the elastic deformation of the engaging piece 55 to close the opening of the shield member 53. The second printed circuit board 56 is superposed on the lid 54.

A printed circuit 56A is provided on the main surface of the second printed circuit board 56, and a plurality of electronic element groups 57 forming an electronic circuit are arranged on the printed circuit 56A. Therefore, the electromagnetic shield device 50 is
The electronic element groups 52 respectively arranged on the first printed circuit board 51 are surrounded by the shield member 53 and the lid 54 to be magnetically shielded.

[0010]

However, since the electromagnetic shield device 50 described above uses the substantially rectangular tubular shield member 53, the thickness of the bottom surface of the lid 54 attached to the shield member 53 is large. The first printed circuit board 51 and the second printed circuit board 5 that are overlapped by a certain size.
There is a problem that the thickness dimension between 6 and 6 becomes large.

For electronic equipment such as portable radios, there is a demand for downsizing and thinning of the entire equipment, and in order to further reduce the size, a lid 54 attached to the shield member 53 is required.
The thickness of the bottom of the can not be ignored.

[0012] Therefore, an object of the present invention is to provide an electromagnetic shield device for an electronic device which surely electromagnetically shields an electronic element group respectively arranged on a printed circuit board and can downsize the entire device. And

[0013]

In order to achieve the above-mentioned object, an electromagnetic shield device for electronic equipment according to the present invention includes a first printed circuit board on which electronic element groups constituting an electronic unit are respectively arranged, An electronic element group formed in a substantially rectangular tube shape and arranged on each of the first printed circuit boards is surrounded by an inner peripheral portion and is arranged on the first printed circuit board 4, and a plurality of connection groove portions are formed at the opening end. A second printed circuit board provided with a ground plane on a facing surface which is overlapped with a shield frame member having a concave shape and an opening of the shield frame member provided on the first printed circuit board in a closed state. And a plurality of conductive elastic members soldered and mounted on the ground plane provided on the second printed circuit board so as to correspond to the connection groove portions provided in the shield frame member.

Further, an elastic member integrally provided with a connecting piece from one end portion having a substantially U-shaped cross section and a connecting convex portion with which the connecting piece of the elastic member abuts are integrally provided on the bottom surface of the connecting groove portion. And a shield frame member.

Further, the first printed board and the second printed board are formed in a multi-layered structure in which a first ground plane parallel to the main surface is sandwiched in the inner layer portion, and the first ground plane and the opening of the shield frame member are formed. A second grounding surface of a substantially rectangular ring shape corresponding to the opening end of the shield frame member is provided on the opposing surface, and a plurality of connecting holes for connecting to the first grounding surface are formed along the second grounding surface. Set up. In the second ground plane, these connecting holes are filled with a conductive material.

Furthermore, the second printed circuit board is provided with electronic element groups on the surfaces facing the electronic element groups provided on the first printed circuit board, respectively. Furthermore, the shield frame member is provided with a partition plate on the inner peripheral wall for partitioning each part of the electronic element group.

[0017]

In the electromagnetic shield device for electronic equipment according to the present invention having the above-described structure, a second grounding surface is provided at the opening of the shield frame member arranged on the first printed circuit board.
By directly overlapping the printed circuit boards, the shield frame member is connected to the ground surface and grounded. That is, the shield frame member arranged on the first printed circuit board was mounted by soldering to the ground surface provided on the second printed circuit board in the plurality of connection groove portions respectively provided at the opening end portions. When the elastic members are fitted into each other, the connection groove portion and the elastic member come into contact with each other, so that the shield frame member is connected to the ground surface via the elastic member and grounded.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electromagnetic shield device 1 applied to a portable wireless telephone as a concrete embodiment of the present invention will be described below.
This will be described with reference to FIGS. 1 to 5. The electromagnetic shield device 1 according to the first embodiment generally includes a first printed circuit board 4 and a shield frame member 5 arranged on the first printed circuit board 4.
And a second printed circuit board 6 which is superposed on the shield frame member 5, and an elastic member 8 which is disposed on the second printed circuit board 6.

A printed circuit 4A is provided on the main surface of the first printed circuit board 4, and an electronic element group 9 including a radio frequency unit 9A is soldered to the printed circuit 4A. .

The shield frame member 5, as shown in FIG.
For example, it is formed of a conductive material such as a copper plate into a substantially rectangular tubular shape. The shield frame member 5 has one opening end portion on the main surface of the first printed circuit board 4 in a state where the electronic element group 9 arranged on the first printed circuit board 4 is surrounded by the inner peripheral portion. Are soldered and arranged at a plurality of positions.

The shield frame member 5 is provided with a plurality of connection groove portions 7 which are recessed at regular intervals over the other opening end portion. The connecting groove portions 7 are integrally provided with substantially arcuate connecting convex portions 7A, which are located substantially at the center of the bottom surface portion.

Elastic members 8 arranged on a second printed circuit board 6 described later are fitted into these connection groove portions 7, respectively. As shown in FIG. 4, the elastic member 8 is made of a phosphor bronze material and has a substantially U-shaped cross section.
A connecting piece 8A is integrally provided from one end portion in parallel with the bottom surface portion 8B. The connecting piece 8A is elastically deformable with the base end as a fulcrum, and comes into contact with the inner peripheral side of the bottom surface 8B of the elastic member 8 by elastically deforming.

A printed circuit 6A is formed on the main surface of the second printed circuit board 6, and a predetermined number of dome-shaped connection terminals 10 and light emitting diodes 16 forming an electronic circuit are respectively formed on the printed circuit 6A. It is provided. These connection terminals 10 correspond respectively to a predetermined number of operation buttons 13 provided on the housing 12 of the portable wireless telephone, and when the operation buttons 13 are pressed, they are connected to other electronic circuits, and The light emitting diode 16 is turned on.
Further, the second printed circuit board 6 is provided with the liquid crystal display board 11 on the printed circuit 6A provided on the main surface thereof.

The second printed circuit board 6 is superposed on a shield frame member 5 which is arranged so as to surround the electronic element groups 9 respectively arranged on the first printed circuit board 4 in an inner peripheral portion, The opening of the shield frame member 5 is closed. Second
The printed circuit board 6 is provided with a ground surface 14 on the opposite surface that abuts the opening of the shield frame member 5, and a plurality of elastic members 8 are provided on the ground surface 14 at regular intervals to form a bottom surface portion 8B. Are soldered and arranged respectively.

These elastic members 8 are the shield frame members 5
When the second printed circuit boards 6 are superposed on each other, they are arranged at the positions of the second printed circuit boards 6 corresponding to the connection groove portions 7 respectively recessed in the shield frame member 5.

Therefore, the shield frame member 5 is disposed on the second printed circuit board 6 in the connection groove portions 7 respectively provided over the opening ends by superimposing the second printed circuit board 6 on each other. The elastic members 8 are fitted together. In the shield frame member 5, when the elastic member 8 is fitted into the connecting groove portion 7, the connecting piece 8A of the elastic member 8 comes into contact with the connecting convex portion 7A provided in the connecting groove portion 7, and the connecting piece 8A is Elastically deform and push in. The connecting piece 8A reliably comes into contact with the connecting convex portion 7A provided in the connecting groove portion 7 by the elastic force caused by being elastically deformed and pushed.

The shield frame member 5 is made up of the elastic member 8
Is provided on the ground surface 14 of the second printed circuit board 6, so that the ground surface 14 provided on the second printed circuit board 6 is reliably and satisfactorily connected via the elastic member 8.
That is, the electronic element groups 9 arranged on the first printed circuit board 4 are reliably electromagnetically shielded by the shield frame member 5.

The electromagnetic shield device 1 described above uses the shield frame member 5 having a substantially rectangular tubular shape. For example, as shown in FIG.
The partition plate 15A, the second partition plate 15B, and the third partition plate 15C may be provided respectively.

The electromagnetic shield device 1 includes a shield frame member 5
By providing the first partitioning plate 15A to the third partitioning plate 15C respectively, the electronic element groups 9 respectively arranged on the first printed circuit board 4 can be arbitrarily partitioned and the first partitioning plate 15A To third partition plate 15
The electronic element groups separated by C can be electromagnetically shielded from each other.

The electromagnetic shield device 1 of the first embodiment
In place of the elastic member 8 provided on the second printed board 6, a coil spring or rubber having electric conductivity may be used.

As described above, in the electromagnetic shield device 1 of the first embodiment, the shield frame member 5 and the second printed circuit board 6 are provided.
By directly superposing them on each other, the lid 54 that constitutes the conventional electromagnetic shield device 50 becomes unnecessary. Therefore, in the electromagnetic shield device 1, the thickness dimension between the first printed circuit board 4 and the second printed circuit board 6 is reduced, so that the entire electronic device including the electromagnetic shield device 1 can be made thin. It can be miniaturized.

In the electromagnetic shield device 1, the second printed circuit board 6 is directly superposed on the shield frame member 5 arranged on the first printed circuit board 4, so that the second printed circuit board 6 is shielded. It is reliably supported by the member 5. Therefore, in the electromagnetic shield device 1, for example, the second printed circuit board 6 on which the housings on which the operation buttons and the like are arranged are overlapped and the connection terminals 10 of the operation buttons are arranged.
As described above, it is suitable for use in an electronic device in which a pressing force applied to a printed circuit board by a button operation is applied.

A second embodiment of the electromagnetic shield device 2 applied to a portable radio telephone will be described with reference to FIGS. 6 to 8. The electromagnetic shield device 2 has substantially the same basic configuration as the electromagnetic shield device 1 of the first embodiment, and includes a first printed circuit board 20 and the first printed circuit board 20.
The shield frame member 21 disposed on the second printed circuit board 20, the second printed circuit board 22 superposed on the shield frame member 21, and the elastic member 29 disposed on the second printed circuit board 20.

A printed circuit 20A is provided on the main surface of the first printed circuit board 20, and an electronic element group 23 including a radio frequency unit 23A is soldered to the printed circuit 20A. . As shown in FIGS. 6 and 7, this first printed circuit board 20 has a first inner layer portion.
The ground plane 25 is formed in a multi-layer structure in which it is sandwiched in parallel with the main surface.

In addition, the first printed circuit board 20 has a second ground plane 26 of a substantially rectangular ring shape along the outer periphery of the main plane.
Are provided so as to surround the electronic element group 23.
This first printed circuit board 20 has a second ground plane 26
A predetermined number of connection holes 26A that are connected to the first ground surface 25 are provided at regular intervals.

The second ground plane 26 is connected to the first ground plane 25 and electrically connected by filling the connection holes 26A with the melted solder. Further, on the first printed circuit board 20,
A printed circuit (not shown) is provided on the back side, and the electronic element groups 30 are arranged in this printed circuit.

The shield frame member 21 is formed of a conductive material such as a copper plate into a substantially rectangular tube shape. The shield frame member 21 has one opening end portion on the main surface of the first printed circuit board 20 in a state where the electronic element group 23 respectively arranged on the first printed circuit board 20 is surrounded by the inner peripheral portion. Are connected to the second ground plane 26 by being soldered at a plurality of positions.

In the shield frame member 21, a plurality of connection groove portions 24 are respectively provided at regular intervals over the other open end portion. These connecting groove portions 24 are located at a substantially central portion of the bottom surface portion and have a substantially arcuate connecting convex portion 24A.
Are provided integrally with each other.

Then, in these connection groove portions 24, elastic members 29 arranged on the second printed circuit board 22 which will be described later.
Are respectively fitted. These elastic members 29 are made of a phosphor bronze material and have a substantially U-shaped cross section, and a connecting piece 29A is integrally provided from one end portion in parallel with the bottom surface portion 29B. The connecting piece 29A is elastically deformable with the base end portion as a fulcrum, and elastically deforms to contact the inner peripheral portion of the bottom surface portion 29B of the elastic member 29.

A printed circuit (not shown) is formed on the main surface of the second printed circuit board 22, and a predetermined number of dome-shaped connection terminals 31 and light emitting diodes 32 forming an electronic circuit are formed on the printed circuit. It is provided. These connection terminals 31 respectively correspond to a predetermined number of operation buttons provided on the casing of a portable wireless telephone (not shown), and when the operation buttons are pressed, they are connected to other electronic circuits and emit light. The diode 32 is turned on.

As shown in FIG. 6, the second printed circuit board 22 has a multi-layered structure in which the third ground plane 27 is sandwiched in the inner layer portion in parallel with the main surface. Further, as shown in FIG. 8, the second printed circuit board 22 is provided with a substantially rectangular annular fourth ground surface 28 along the outer peripheral portion on the opposing surface that abuts the opening of the shield frame member 21. ing.

On the second printed board 22, an electronic element 33 is arranged on the inner peripheral side of the fourth ground plane 28. That is, in the second printed circuit board 22, the fourth ground plane 28 is formed in a substantially rectangular ring shape,
The electronic element 33 can also be arranged on the surface facing the shield frame member 21.

The second printed circuit board 22 has a fourth
A predetermined number of connection holes 28 </ b> A that are connected to the first ground surface 28 are formed along the ground surface 28 at regular intervals. The fourth ground surface 28 is connected to the third ground surface 27 by filling the connection holes 28A with molten solder, and is electrically connected.

The second printed circuit board 22 is
The shield frame member 2 is provided so as to surround the electronic element group 23 provided on the first printed circuit board 20 in the inner peripheral portion.
The shield frame member 21 is superposed on the shield frame member 21 to close the opening. As shown in FIG. 8, the second printed circuit board 22 is provided with a substantially rectangular fourth ground surface 28 along the outer periphery of the opposing surface that abuts the opening of the shield frame member 21. A plurality of elastic members 29 are arranged on the fourth ground surface 28 with a fixed interval and soldered to the bottom surface portion 29B.

These elastic members 29 are provided when the second printed circuit board 22 is superposed on the shield frame member 21.
The shield frame members 21 are arranged at the positions of the second printed circuit board 22 corresponding to the connection groove portions 24 respectively provided in the shield frame member 21.

Therefore, the shield frame member 21 has the second
When the printed circuit boards 22 are overlapped with each other, the elastic members 2 disposed on the second printed circuit boards 22 in the connection groove portions 24 respectively provided over the opening end portions.
9 are fitted together. In the shield frame member 21, the elastic member 29 is fitted into the connecting groove portion 24, so that the elastic member 29 is attached to the connecting convex portion 24A provided in the connecting groove portion 24.
The connecting piece 29A comes into contact with the connecting piece 29A to elastically deform and push it in. The connecting piece 29A is elastically deformed and pushed into the connecting groove portion 2 by the elastic force.
No. 4 connecting projection 24A is surely abutted.

Since the elastic member 29 is provided on the fourth ground surface 28 of the second printed circuit board 22, the shield frame member 21 is provided on the second printed circuit board 22 via the elastic member 29. It is securely and satisfactorily connected to the provided fourth ground plane 28. That is, the electronic element groups 23 arranged on the first printed circuit board 20 are reliably electromagnetically shielded by the shield frame member 21.

Although the shield frame member 21 having a substantially rectangular tubular shape is used in the electromagnetic shield device 2 described above, a predetermined number of partition plates may be provided on the inner peripheral wall of the shield frame member 21, for example. In the electromagnetic shield device 2, the shield frame member 21 is provided with partition plates, so that the electronic element groups 23 respectively disposed on the first printed circuit board 20 are arbitrarily partitioned and are partitioned by these partition plates. The respective electronic element groups can be electromagnetically shielded from each other.

Further, the electromagnetic shield device 2 of the second embodiment
Instead of the elastic member 8 provided on the fourth ground surface 28, a coil spring or rubber having electrical conductivity may be used.

As described above, in the electromagnetic shield apparatus 2 of the second embodiment, the lid 54 constituting the conventional electromagnetic shield apparatus 50 is constructed by directly superposing the second printed board 22 on the shield frame member 21. Is unnecessary. Therefore, the electromagnetic shield device 2 includes the first printed circuit board 20.
Since the thickness between the second printed circuit board 22 and the second printed circuit board 22 is reduced, the entire electronic device including the electromagnetic shield device 2 can be thinned and downsized.

The second printed circuit board 22 can also be provided with the electronic element 33 on the surface facing the shield frame member 21. Therefore, the electromagnetic shield device 2 is arranged on the electronic element group 23 respectively arranged on the main surface of the first printed board 20 and on the facing surface of the second printed board 22 facing the electronic element group 23. Electronic element 33 installed
Since the and can be surrounded by the inner peripheral portion of the shield frame member 21, the entire device can be made thin and small.

The electromagnetic shield device according to the present invention is
It is not limited to mobile wireless devices such as mobile phones,
For example, it may be used for other electronic devices such as a video camera and a computer.

[0053]

As described above, according to the electromagnetic shield device for electronic equipment of the present invention, the second printed circuit board is directly superposed on the shield frame member disposed on the first printed circuit board. By doing so, the entire device can be downsized. Further, this electromagnetic shield device for an electronic device is particularly suitable for use in an electronic device including a printed circuit board provided with a connection terminal such as an operation button and to which a pressing force applied by a button operation is applied.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an electromagnetic shield device according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing the electromagnetic shield device.

FIG. 3 is a perspective view showing a shield frame member used in the electromagnetic shield device.

FIG. 4 is a perspective view showing an elastic member used in the electromagnetic shield device.

FIG. 5 is a perspective view showing an example of a shield frame member used in the electromagnetic shield device.

FIG. 6 is a vertical sectional view showing an electromagnetic shield device according to a second embodiment.

FIG. 7 is a perspective view showing a main part of the electromagnetic shield device.

FIG. 8 is a perspective view showing a main part of the electromagnetic shield device.

FIG. 9 is an exploded perspective view showing a conventional electromagnetic shield device.

FIG. 10 is a vertical cross-sectional view showing a conventional electromagnetic shield device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electromagnetic shield device 4 1st printed circuit board 5 Shield frame member 6 2nd printed circuit board 7 Connection groove part 8 Elastic member 9 Electronic element group 14 Ground plane

Claims (5)

[Claims] 1. A first printed circuit board on which electronic element groups constituting an electronic unit are respectively disposed, and an electronic element group formed on a substantially rectangular tubular shape and disposed on each of the first printed circuit boards are included. A shield frame member which is disposed on the first printed circuit board 4 so as to be surrounded by the peripheral portion and in which a plurality of connection groove parts are respectively provided at the opening end, and a shield frame member which is disposed on the first printed circuit board. A second printed circuit board having a ground surface provided on the opposing surfaces which are overlapped with each other in a state where the opening of the second printed circuit board is closed, and the shield frame member is provided with a recess on the ground surface provided on the second printed circuit board. The shield frame member provided on the first printed circuit board is provided with the second printed circuit board in the opening. When superposed Electromagnetic shielding device of an electronic apparatus, characterized in that it is connected to a ground plane provided on the second printed board via an elastic member which is fitted to the connection groove. 2. An elastic member integrally formed with a connecting piece from one end portion having a substantially U-shaped cross section, and a connecting convex portion with which the connecting piece of the elastic member abuts are integrally provided on a bottom surface of the connecting groove portion. And a shield frame member provided on the first printed circuit board, and the shield frame member provided on the first printed circuit board is a connection piece of an elastic member fitted into the connection groove when the second printed circuit board is superposed on the opening. 2. The electromagnetic shield device for an electronic device according to claim 1, wherein the connection convex portion provided on the bottom surface of the connection groove portion is connected to the ground surface provided on the second printed circuit board. . 3. The first printed circuit board and the second printed circuit board are formed in a multi-layered structure in which a first ground plane parallel to the main surface is sandwiched in an inner layer section, and the first ground plane and the opening section of the shield frame member are formed. A substantially rectangular annular second ground surface corresponding to the open end of the shield frame member is provided on the opposing surface and the second ground surface is provided.
A plurality of connecting holes for connecting to the first grounding surface are formed along the grounding surface of the first grounding surface, and the second grounding surface is filled with a conductive material to form the first grounding surface. The electromagnetic shield device for an electronic device according to claim 1 or 2, wherein the electromagnetic shield device is connected to a ground plane. 4. The second printed circuit board is provided with electronic element groups on a surface facing the electronic element groups respectively provided on the first printed circuit board, and the electronic element groups are respectively provided on the first printed circuit board. 4. The electromagnetic shield device for electronic equipment according to claim 3, wherein the shielded electronic element group and the electronic element groups respectively arranged on the second printed circuit board are surrounded by the inner peripheral portion of the shield frame member. . 5. The electronic device according to claim 1, wherein the shield frame member is provided with a partition plate for partitioning each portion of the electronic element group on the inner peripheral wall. Electromagnetic shield device.