JP3505386B2 - Electronic equipment shield structure - Google Patents

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 protecting an electronic component from external noise in an electronic device such as a VTR (video tape recorder) having an electronic component arranged in a casing.

[0002]

2. Description of the Related Art Conventionally, in a VTR, as shown in FIG. 11, a mechanism (92) equipped with various mechanisms such as a cassette loading mechanism is arranged inside a resin main body case (8) having an open upper surface. At the same time, electronic parts such as a rotary head cylinder (9) and an audio / control head (91) are arranged along the running path of the magnetic tape, and a resin front panel is provided on the front surface of the main body case (8). (8
1) is attached, and a metal top plate (82) is attached to the upper opening. In the VTR, a metal top plate (8
2) serves as a shield plate to protect the rotary head cylinder (9) and audio / control head (91) from external noise. The top plate (82) has a thickness of 0.5 mm, for example.
It is manufactured by pressing a metal plate of a certain size.

[0003]

However, in the conventional VTR, since the top plate (82) has a bent shape in which side plate portions are projected on both sides of the flat plate portion, the equipment for press working is complicated. However, in order to maintain such a bent shape, a metal plate having a relatively large thickness is used as a material as described above, which causes an increase in manufacturing cost. Therefore, an object of the present invention is to provide a shield structure for an electronic device that exhibits a sufficient shielding effect for electronic parts and can reduce the manufacturing cost.

[0004]

A shield structure for an electronic device according to the present invention is an electronic device in which an electronic component to be protected from external noise is provided in a casing (10), wherein the casing (10) is Box-shaped body case with open top (1)
And a top plate (3) for closing the upper opening of the main body case (1), the main body case (1) and the top plate (3) being made of resin,
A flat plate-shaped metal shield plate (5) is attached to the inner surface of the top plate (3) at a position where the electronic component is covered.

The top plate (3) is attached with the shield plate (5).
The bay where the central part of the inner surface to be projected protrudes toward the mechanism (4) side
The shield plate (5) is molded into a curved shape and the shield plate (5) is a top plate.
Around the inner surface of the top plate (3), which is molded into a curved shape along (3)
The ribs (35) for fusion that protrude from the central and central parts seal
It penetrates through the plate (5) and its tip end is sealed by heating and melting.
It is fixed to the rudder plate (5). In the casing (10)
Mechanism with a metal part that serves as an electrical ground (4)
And the shield plate (5) has gold of the mechanism (4).
A plurality of protrusions (52) to be in contact with the base are formed, and the protrusions (5
By contacting the metal part of mechanism (4) with 2)
The curved shape due to elastic deformation of the plate (3) and the shield plate (5)
Has been corrected to a flat shape.

In the shield structure of the present invention described above,
The convex portion (52) of the shield plate (5) is attached to the upper surface of the mechanism (4) (metal
Part), the top plate (3) and the shield plate (5) are elastically deformed.
Since the curved shape is corrected to a flat shape,
By the elastic restoring force of the top plate (3) and the shield plate (5),
The part (52) is pressed against the upper surface of the mechanism (4), and the shield plate
A reliable electrical connection between (5) and mechanism (4) is achieved.
The shield plate (5) is connected to electrical ground
ing.

In the shield structure of the present invention, the ceiling
The plate (3) is made of resin and the shield plate (5) is flat
Therefore, the top plate (3) and the shield plate (5) can be easily manufactured.
Therefore, it is possible to reduce the manufacturing cost compared to the conventional metal top plate.
It is possible. Also, for electronic parts that require a shield plate (5)
Since it is covered and deployed, noise (electromagnetic waves,
These noises will
It is blocked by the shield plate (5).

Incidentally, the shield plate (5) is provided outside the electronic component.
Shaped to the smallest size that can be protected from incoming noise
It is enough. By this, the shield plate (5)
Material costs can be reduced and equipment weight can be reduced.

[0009]

According to the shield structure for an electronic device of the present invention, it is possible to obtain a sufficient shield effect for electronic components and reduce the manufacturing cost.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment in which the present invention is applied to a VTR will be specifically described with reference to FIGS.
The VTR according to the present invention includes a flat casing (10) as shown in FIG. 1, and the casing (10) has a box-shaped main body case (1) having an open top surface as shown in FIGS. 2 and 3. A front panel (2) attached to the front opening of the body case (1) and a top plate (3) attached to the top opening of the body case (1) are combined. Body case
A mechanism (4) such as a cassette loading mechanism (6) is installed in (1). Also, on the front panel (2),
A cassette insertion opening (21) for inserting a cassette toward the cassette loading mechanism (6) is provided. still,
The body case (1), front panel (2) and top plate (3) are
Each is made of polystyrene.

On the inner surface of the top plate (3), a rotary head cylinder and an audio / control head (neither shown)
Facing the rear area in the body case (1) where
The top shield plate (5) made of metal and having a rectangular shape is fixed. Further, a metal back shield plate (7) is fixed to the back surface of the body case (1) as shown in FIGS. 3 and 6. Both shield plates (5) and (7) each have a thickness of 0.3 m.
It is produced by cutting a metal plate of m.

As shown in FIG. 7, a plurality of fusing ribs (35) are provided on the inner surface of the top plate (3) at the peripheral portion and the central portion thereof, while the shield plate (5) is Corresponding to each fusion rib (35), a plurality of square holes (51) are opened, and these square holes (51)
The ribs (35) for fusing are pierced through and the tip of the rib protruding from the square hole (51) is heated and melted to fix the top shield plate (5) to the inner surface of the top plate (3). Also, shield plate
In (5), a plurality of convex portions (52) protruding toward the mechanism side are formed by drawing along the long side on the front panel side.

The top plate (3) is provided with a pair of left and right side eaves (33) (33), and the inner side of the top plate (3) extends along each side eaves (33).
A plurality of assembly ribs (34) are provided so as to project. Also, the top plate (3)
A plurality of tongue pieces (31) are provided to protrude toward the front panel side.

As shown in FIG. 9, the front panel (2) is provided with a plurality of assembling ribs (22) projecting toward the main body case along the upper eaves (24). In (22),
The engagement hole (23) is opened. Also, front panel (2)
On the lower eaves (27), a plurality of projecting pieces (25) are formed, and an engaging hole (26) is formed in each projecting piece (25).

As shown in FIG. 2, in the main body case (1), the assembling ribs (22) are provided at the upper end portion on the front panel (2) side.
A plurality of hook pieces (12) are provided so as to correspond to the engaging holes (23). Further, as shown in FIG. 3, the main body case (1) is
A plurality of hook pieces (13) are provided at the lower end portion of the front panel (2) side so as to correspond to the engaging holes (26) of the projection pieces (25).

When assembling the front panel (2) into the main body case (1), the front panel (2) is attached to the main body case (1).
Push it toward the front opening of the front panel and attach the hook pieces (12) and (13) of the main body case (1) to the front panel as shown in FIGS. 5 and 6.
Engage with the engaging holes (23) and (26) of (2). As a result, the front panel (2) is fixed to the body case (1).

Thereafter, when the top plate (3) is assembled to the main body case (1), the tongue piece (31) of the top plate (3) is attached to the front panel.
While inserting it between the upper eaves portion (24) and the assembly rib (22) of (2), the side eaves portion (33) and ribs (3) of the top plate (3) are inserted as shown in FIG.
The side plate end portion (11) of the main body case (1) is fitted into the space between (4) and the top plate (3) is put on the upper opening of the main body case (1).
Then, using the plurality of screws (32) shown in FIG.
The rear eaves (36) of (3) and the back plate (14) of the main body case (1) are fastened to each other. As a result, the top plate (3) is fixed to the main body case (1) as shown in FIG.

By fixing the top plate (3) to the main body case (1) as described above, the projections (52) of the top shield plate (5) installed on the inner surface of the top plate (3) are The top surface shield plate (5) and the mechanism (4) are electrically connected to each other by contacting the top surface (41) of the mechanism (4) arranged in the main body case (1). ) Is taken.

In a more specific shape, the top plate (3) has a curved shape in which the central portion of the inner surface to which the shield plate (5) is to be attached protrudes toward the mechanism, as shown in FIG. 10 (a).
(For example, the maximum protrusion amount = about 5 mm). or,
The top shield plate (5) is also formed in the same curved shape. Therefore, as described above, the peripheral portion of the top plate (3) is attached to the main body case.
In the process of fixing to the (1), the convex portion (52) of the shield plate (5) hits the upper surface (41) of the mechanism (4), and the top plate (3) and the top shield plate (5) are elastically deformed, As shown in FIG. 10B, the curved shape is corrected to a flat shape. As a result,
Due to the elastic restoring force of the top plate (3) and the top shield plate (5), the convex portion (52) is pressed against the upper surface (41) of the mechanism (4),
A reliable electrical connection between the shield plate (5) and the mechanism (4) will be achieved.

In the above VTR, the top shield plate
Since (5) covers the rotary head cylinder and the audio / control head to protect these electronic components from external noise, normal recording / reproducing operation is possible regardless of external noise. Further, since the top plate (3) which should function as the lid of the main body case (1) is made of resin, it is easier to manufacture than the conventional metal top plate, and the manufacturing cost is reduced and the weight is reduced. Is planned.

The top shield plate (5) which should perform the shield function is thinner than the conventional top plate, and is a rectangular metal plate having a plurality of square holes (51) and convex portions (52). Since it only has a simple structure in which the above is formed, the equipment for press working is much simpler than the equipment for manufacturing the top plate of the conventional complicated structure. The cost can be reduced. Further, the top shield plate (5) covers the rotary head cylinder and the audio / control head so as to protect these electronic components from noise, that is, the inner surface of the top plate (3). About 2 in area
Since it suffices to have a width of one-half, weight reduction and material cost reduction can be achieved by this.

The configuration of each part of the present invention is not limited to the above embodiment, and various modifications can be made within the technical scope described in the claims. For example, the shield structure of the present invention is V
Not limited to TR, it can be applied to various electronic devices such as TV receivers, information processing devices, and measuring devices.

[Brief description of drawings]

FIG. 1 is a perspective view showing the appearance of a VTR having a shield structure according to the present invention.

FIG. 2 is an exploded perspective view of the casing as viewed from diagonally above.

FIG. 3 is an exploded perspective view of the casing as viewed from diagonally below.

FIG. 4 is a perspective view showing a state in which a top plate is disassembled from a main body case.

FIG. 5 is a perspective view showing a state in which a front panel is attached to a main body case.

FIG. 6 is a perspective view showing a back shield plate attached to the back surface of the main body case.

FIG. 7 is an exploded perspective view of a top plate and a top shield plate.

FIG. 8 is a sectional view of an assembled state in which a top plate is attached to the main body case.

FIG. 9 is a perspective view of the front panel as viewed from the inside.

FIG. 10 is a cross-sectional view showing curved shapes of the top plate and the top shield plate and a contact state with the mechanism upper surface.

FIG. 11 is an exploded perspective view of a conventional VTR.

[Explanation of symbols]

(10) Casing (1) Body case (2) Front panel (3) Top plate (4) Mechanism (5) Top shield plate (52) convex (6) Cassette loading mechanism

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Claims (2)

(57) [Claims] 1. An electronic device comprising an electronic component to be protected from external noise in the casing (10), wherein the casing (10) is a box-shaped main body case (1) having an open top surface.
And a top plate (3) for closing the upper opening of the main body case (1), the main body case (1) and the top plate (3) being made of resin,
The inner surface of the top plate (3), in a position for covering the electronic parts, and plate-shaped metal shield plate (5) is attached, heaven
The plate (3) is an inner surface to which the shield plate (5) is to be attached.
Molded into a curved shape with the central part protruding toward the mechanism (4).
And the shield plate (5) is curved along the top plate (3).
It is molded into a shape and projects on the inner and outer peripheral parts of the top plate (3).
The plurality of fusion ribs (35) installed penetrate the shield plate (5).
The tip of the lever is fixed to the shield plate (5) by heating and melting
There is an electrical ground inside the casing (10).
A mechanism (4) with a metal part that becomes
The rudder plate (5) should contact the metal part of the mechanism (4).
A plurality of protrusions (52) are formed, and the protrusions (52) are the mechanism.
By touching the metal part of (4), the top plate (3) and the sea
The curved plate (5) is elastically deformed so that the curved shape is flat.
A shield structure for electronic devices characterized by being corrected . 2. The top plate (3) controls the electronic component to be an external noise.
Formed to the smallest size that can be protected from
Shield structure according to claim 1, there.