JPH0719196Y2 - Detachable electromagnetic shield structure for electronic device housing - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic shield structure for an electronic equipment housing, and more particularly to a lid member for closing an attachment / detachment opening of an electronic component provided in the electronic equipment housing, and a lid member attached to the lid member by elastic force. The present invention relates to a detachable electromagnetic shield structure including an FG (frame ground) metal fitting that supports the inside of the detachable opening.

[0002]

2. Description of the Related Art Electromagnetic interference (EMI) in electronic devices has become an important issue as the number of noise sources increases and the speed of electronic devices increases due to the spread of digital devices.
Various techniques have been developed and proposed to address I regulations. Above all, in order to suppress so-called radiated noise in which noise radiated in the air from electronic devices interferes with other devices as electromagnetic waves, electronic components used in electronic devices,
In particular, it is necessary to properly ground the printed wiring board and at the same time take measures to shield it so that noise does not leak from the equipment housing or power cord. Therefore, for example, when a desired printed wiring board is detachably mounted on the electronic device from the outside of the housing for the purpose of, for example, adding an option to a personal computer, the printed wiring board attachment / detachment opening provided in the housing is surely secured. Electromagnetic shield measures are required. Conventionally, in such a case, the printed wiring board is inserted into the housing while being supported by a lid member made of metal, and the lid member substantially closes the attachment / detachment opening when the insertion is completed. The lid member that fixedly supports the printed wiring board can be detachably supported by the attachment / detachment opening peripheral edge portion, the gap between the lid member and the peripheral edge portion is closed, and further, the housing ground of the printed wiring board, that is, FG (frame). For the purpose of taking a ground), a leaf spring-shaped FG metal fitting utilizing elastic force is attached to the lid member and used.

FIG. 6 shows the above-mentioned FG metal fitting used conventionally together with a lid member. As shown, the FG fitting 1 is V
The bent portion 2 is attached to the inside of a lid member 3 having a U-shaped cross section and having a U-shaped cross-section, and the bent portion 2 is removed from holes 5a and 5b provided in opposite side portions 4a and 4b of the lid member 3, respectively. When the lid member 3 is inserted into the attachment / detachment opening of the device housing, the bent portion 2 is pressed inward by the peripheral edge of the attachment / detachment opening, and the FG metal fitting 1 moves the free end portion 6 at the tip of the bent portion 2. The structure is such that the top end portion 7 of the bent portion 2 is pressed against the peripheral edge portion of the attachment / detachment opening while being displaced inward.

[0004]

[Problems to be Solved by the Invention] Such a conventional FG
In addition to the original FG function, the metal fitting reduces the gap between the lid member and the peripheral edge portion of the attachment / detachment opening to enhance the electromagnetic shielding effect, and enables the lid member to be detachably supported by the peripheral edge portion of the attachment / detachment opening. , When the bending end is pushed inward when inserted into the attachment / detachment opening and its free end is displaced inside the lid member, the free end is formed on the pattern surface of the printed wiring board fixedly supported by the lid member. May come into contact with each other and cause a short circuit failure. For this reason, it is necessary to provide a predetermined space between each opposing side portion of the lid member and the printed wiring board, which is a bottleneck for downsizing the device and high-density mounting of the small device.

The present invention has been made to solve such a problem, and its purpose is to provide a reliable electromagnetic shield effect without causing a short circuit between the FG metal fitting and the printed wiring board. An object of the present invention is to provide a detachable electromagnetic shield structure for an electronic device housing, which can promote miniaturization of devices and high-density mounting of small devices.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention has a novel shape of F that does not cause short circuit failure.
The present invention provides a detachable electromagnetic shield structure configured by attaching a G metal fitting to a lid member. That is, according to the present invention, a detachable lid member having a U-shaped cross section that closes the opening of the electronic device housing, and an FG fitting attached to the lid member and supporting the lid member in the opening by elastic force are provided. In the structure including, the lid member has at least a hardness capable of holding its own shape, and has a groove hole on each of its opposing sides,
The FG fitting includes a support base fixed to the inside of the facing side of the lid member, and a U-shaped curve extending from the support base and overlapping the groove on the outside of the facing side to form a support base. An electronic device comprising: a leaf spring portion that extends substantially in parallel and is elastically displaceable in the groove hole with a tip as a free end; and an outwardly projecting portion formed in the leaf spring portion. A detachable shield structure for the housing is provided.

[0007]

In the above structure, when the lid member to which the FG metal fitting is attached is inserted into the opening of the electronic equipment housing, the leaf spring portion of the FG metal fitting arranged on the outer side of the opposing side of the lid member opens the protrusion. It is pressed toward the support base while being brought into contact with the peripheral edge of the part, and is elastically displaced into the slot on the opposite side. At this time, the lid member and the support base portion of the FG fitting fixed to the lid member are not deformed, and the lid member is supported in the opening by the elastic force of the leaf spring portion. At the same time, the protrusion provided on the leaf spring portion reduces the gap between the lid member and the peripheral edge of the opening.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a perspective view of a detachable electromagnetic shield structure according to an embodiment of the present invention. The detachable electromagnetic shield structure shown in FIG. 1 includes a metallic lid member 10 for fixedly supporting a printed wiring board P to be detachably mounted on an electronic device, and an FG metal fitting 12 attached to the lid member 10. Consists of. The lid member 10 fixedly supports the printed wiring board P as shown in FIG. 2 and substantially closes the attachment / detachment opening 16 provided in the electronic device housing 14. The lid member 10 has a U-shaped cross section, and is provided with a plurality of slots 20 aligned in the longitudinal direction on each of the pair of opposed side portions 18 while maintaining a hardness capable of holding at least its own shape. The FG metal fitting 12 is made of a conductive thin sheet metal, and has a support base 22 that is bent in a U-shape and is fixed in contact with the inner surface of the lid member 10, and opposite side portions 22 a of the support base 22.
A leaf spring portion 24 is provided that extends from the tip and curves outward in a U-shape, and extends substantially parallel to the facing side portion 22a of the support base 22 outside the facing side portion 18 of the lid member 10. The leaf spring portion 24 has notches 26 at predetermined intervals in the longitudinal direction, and as a result, a plurality of leaf springs that can be displaced independently of each other at a position overlapping the slot 20 provided in the opposite side portion 18 of the lid member 10. Piece 24a is formed. Each leaf spring piece 24a has a protruding portion 28 protruding outward near the center thereof.
Equipped with.

The FG metal fitting 12 detachably supports the lid member 10 fixedly supporting the printed wiring board P as described above in the attachment / detachment opening 16 of the electronic device housing 14, and at the same time, the lid member 10
And the gap between the peripheral edge of the attachment / detachment opening is reduced. As shown in FIG. 3, the FG metal fitting 12 according to this embodiment is connected to the printed wiring board P via the connector 30, and is further sandwiched between the connector 30 and the lid member 10 by a screw (not shown) together with the connector 30. It is fastened and fixed to the lid member 10 together. Further, the gap between the opposing side portion 22a of the support base 22 of the FG metal fitting 12 and each leaf spring piece 24a is substantially equal to or slightly larger than the thickness of the opposing side portion 18 of the lid member 10. As will be described later, even when an external force is applied to the leaf spring piece 24a, the support base portion 22 of the FG metal fitting 12 hardly deforms.

When the detachable electromagnetic shield structure constructed as described above is inserted into the attach / detach opening 16 of the electronic equipment housing 14 with the printed wiring board P fixedly supported, as shown in FIG. Each of the leaf spring pieces 24a is pressed inward with its projection 28 abutting against the frame portion 32 at the peripheral edge of the attachment / detachment opening 16, and thereby into each slot 20 provided in the opposite side portion 18 of the lid member 10. Displace the free tip. At this time, the pressing force of the frame portion 32 hardly deforms the support base portion 22 of the FG metal fitting 12 as described above, and the lid member that fixedly supports the printed wiring board P is elastically restored by the displacement of only the leaf spring piece 24a. 10 is supported in an attachment / detachment opening 16 of an electronic device housing 14. In this way, even when mounted in an electronic device,
Since the support base portion 22 of the FG metal fitting 12 arranged inside the lid member 10 is not displaced, there is a very small gap between the printed wiring board P fixed to the lid member 10 and the opposite side portion 18 of the lid member 10. It suffices to form S, which eliminates useless space and promotes miniaturization of equipment and high density of small equipment.

As described above, the FG metal fitting 12 sandwiches the facing side portion 18 of the lid member 10 between the facing side portion 22a of the support base 22 and each leaf spring piece 24a, and also the connector 30 of the printed wiring board P.
Since the lid member 10 and the lid member 10 are screwed together, it is not necessary to join the lid member 10 and the FG fitting 12 by spot welding or the like. Further, since the support base 22 of the FG fitting 12 covers almost the entire inner surface of the lid member 10, the lid member 10 does not necessarily have to be made of metal. On the other hand, as in the modified example shown in FIG. 4, the FG metal fittings 12 ′, which are formed by dividing the support base portion 22 of the FG metal fitting 12 and leave only the facing side portions 22 a, are provided on the facing side portions 18 of the lid member 10. In the case of the attachment, it is necessary to join the FG metal fitting 12 'and the lid member 10 by spot welding 34 or the like in order to obtain the same effect. Also, the lid member 10 must be made of metal.

The protrusions 28 provided on each of the leaf spring pieces 24a of the FG metal fitting 12 form a contact for taking the ground of the casing of the printed wiring board P fixedly supported by the lid member 10 and the lid member 10 and the electronic component. By arranging at a predetermined interval (about 15 mm in this embodiment) in the gap between the frame 32 and the peripheral edge of the attachment / detachment opening of the equipment housing 14, it is possible to reduce the gap and effectively prevent radiation noise leaking from the electronic equipment housing 14. It forms an electromagnetic shield. Here, instead of the protrusion 28, the same effect can be obtained even if the tip end (free end) of each leaf spring piece 24a is bent outward in a V-shape as shown in FIG. Is obtained. Further, the slot 20 provided on the opposite side portion 18 of the lid member 10 within a range that does not affect the rigidity of the lid member 10.
Of the leaf spring shown in FIG.
Similarly, by extending 24a in the longitudinal direction (see FIG.
(See (b)), the electromagnetic sealing degree of the attachment / detachment opening 16 can be further enhanced.

[0013]

As described above, according to the present invention, one of the parallel portions of the U-shaped curved portion of the FG metal fitting is fixed to the inside of the opposing side portion of the lid member as a support base, and the other is a leaf spring portion to be the lid member. Is arranged displaceably outside the opposing side portion of the plate spring, and when the leaf spring portion is pressed inward by an external force, the free end portion of the leaf spring portion is displaced into the slot provided in the opposing side portion of the lid member. Therefore, when inserted into the opening of the electronic device housing, the leaf spring portion is pressed by the peripheral edge of the opening and displaced into the slot, but the support base inside the lid member does not deform. Therefore, a short gap does not occur only by providing a small gap between the printed wiring board fixed to the lid member and the opposing side portion of the lid member, thereby eliminating a wasteful space and reducing the size of the device. High-density mounting of small equipment is promoted.

[Brief description of drawings]

FIG. 1 is a perspective view of a detachable electromagnetic shield structure according to an embodiment of the present invention.

2 is an illustration of how to use the structure of FIG. 1. FIG.

FIG. 3 is a cross-sectional view when the structure of FIG. 1 is inserted inside an electronic device housing.

FIG. 4 is a sectional view of a modification of the embodiment of FIG.

FIG. 5 is a diagram of another embodiment, which is a sectional view (a) and a perspective view (b).

FIG. 6 is a cross-sectional view of a conventional electromagnetic shield structure.

[Explanation of symbols]

 10 ... Lid member 12 ... FG metal fitting 18 ... Opposing side part 20 ... Groove hole 22 ... Support base part 24 ... Leaf spring part 24a ... Leaf spring piece 28 ... Projection part

Claims (1)

[Scope of utility model registration request] 1. A removable lid member having a U-shaped cross section for closing an opening of an electronic device housing, and an FG metal fitting attached to the lid member to support the lid member in the opening by elastic force. In the detachable electromagnetic shield structure for an electronic device housing, the lid member has at least a hardness capable of holding its own shape, and a slot is provided on each of opposite sides thereof. A support base fixed to the inside of the opposite side, and a U-shaped curve extending from the support base and overlapping the groove on the outside of the opposite side and extending substantially parallel to the support base, and A detachable electromagnetic shield structure for an electronic device housing, comprising a leaf spring portion that is elastically displaceable in the slot as a free end, and an outwardly projecting portion formed on the leaf spring portion.