JPH049743Y2 - - Google Patents

Description

[Detailed explanation of the invention] [Summary] An elastic conductive member is interposed between the shield plate mounted on a printed board and the chassis, and the shield plate is brought to a reliable ground potential to improve product reliability. .

[Industrial application field]

The present invention relates to a grounding structure for a shield plate mounted on a printed circuit board, and more particularly to a grounding structure for a shield plate in which an elastic conductive member is interposed between the shield plate and the chassis.

When a mobile radio is installed, such as a mobile terminal such as a car phone, it does not cause large vibrations or shocks to the equipment when driving on a flat road, but when it is driven in a wilderness,
When driving on roads in the mountains, etc., large vibrations and shocks are applied to the installed equipment, so the earth potential shield plate attached to the printed circuit board that carries the electronic circuit inside the equipment may come into contact with the chassis etc. due to the vibrations and shocks. Since the parts are separated and the ground potential cannot be maintained reliably, there is a need for an improved grounding structure of the shield plate that can maintain the ground potential without causing the contact parts to separate even with some vibration or impact.

[Conventional technology]

Figures 2 and 3 are diagrams explaining the grounding structure of a conventional shield plate. Figure 2a is a side sectional view when installed normally, Figure 3b is a side sectional view when it is abnormal, and Figure 3a is a side sectional view when it is installed abnormally. is a side sectional view with a line-contact conductive member attached,
b is a side cross-sectional view in which a two-wire contact conductive member is attached.

FIG. 2 shows a structure in which predetermined circuit components 2 are mounted on a printed board 1, and circuits that require shielding are shielded from above and below the printed board 1 with a pair of shield plates 3 and 4. However, due to variations in the dimensions of the shield plates 3 and 4 or assembly errors during assembly, incomplete contact may occur as shown in FIG. 2b.

FIG. 3 was made to eliminate the drawback explained in FIG. 6 is attached to the shield plate 4 to create a structure in which the conductive member 6 does not separate even if there is some variation in the dimensions of the shield plates 3 and 4 or an assembly error during assembly.
A two-wire contact conductive member 7 made of an elastic metal, such as a phosphor bronze plate, is attached to the lower surface of the ground to provide more reliable grounding.

[Problem that the invention attempts to solve]

Regarding the above-mentioned conventional shield plate grounding structure, in the former case (Fig. 2), due to variations in the dimensions of the shield plate or assembly errors during assembly,
There is a problem of incomplete contact, and in the latter case (Fig. 3), although the structure is a line contact, it becomes a point contact due to the unevenness of the plane of the conductive member.
In addition, contact may become incomplete due to vibrations and shocks.
There was a problem in that the characteristics varied.

[Means for solving problems]

The present invention solves the above problems and provides a grounding structure for a shield plate that reliably maintains the ground potential.

That is, a grounding structure between a shield plate mounted on a printed board and a chassis is formed by forming a plurality of grooves in the corresponding portions of the shield plate and the chassis, and forming an elastic conductive structure between the shield plate and the chassis. This problem can be solved by forming a contact member made of conductive rubber, or a rod-shaped rubber with a conductive wire wound around it.

[Effect]

The grounding structure of the shield plate described above is such that a groove into which the conductive member is fitted is formed in the chassis, and a conductive elastic member is interposed in this groove, so that the chassis and the conductive member are in surface contact, and the shield plate and the conductive member are in surface contact. Even in the worst case, there is a line contact, which reduces the variation in characteristics.

〔Example〕

FIG. 1 is a diagram illustrating an embodiment of the present invention.
Figure a is a side sectional view, b is a perspective view of the conductive rubber, and c
2 is a perspective view of the contact member, in which the same parts as in FIG. 2 are designated by the same reference numerals.

FIG. 1a shows a printed board 1 with predetermined circuit components 2.
The structure is such that a circuit that requires shielding is shielded from above and below the printed circuit board 1 by a pair of shield plates 3 and 4. In order to bring the shield plate 4 into surface contact with the chassis 5, a plurality of strips (in the drawings) are installed on the chassis 5. In this case, grooves 51 into which the conductive members 8 (2) are inserted are provided.

Then, in this groove 51, a conductive wire 11 made of a good conductive material such as monel is inserted into the rod-shaped conductive rubber 9 shown in FIG. 1b or the rod-shaped rubber 10 made of silicone rubber or the like shown in FIG. The wound contact member 12 is inserted, and the shield plate 4 is mounted on the conductive rubber 9 or the contact member 12 in a state that resists the elasticity of the conductive member 8.

[Effect of idea]

As is clear from the above explanation, according to the present invention, the shield plate and the chassis are in surface contact via the conductive member, so it is possible to achieve near-perfect grounding and improve the characteristics. This makes it extremely effective when applied to in-vehicle radio, etc.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating an embodiment of the present invention.
Figure a is a side sectional view, b is a perspective view of the conductive rubber, and c
is a perspective view of the contact member, Figures 2 and 3 are diagrams explaining the grounding structure of a conventional shield plate, Figure 2a is a side sectional view when installed normally, and Figure 2b is a side sectional view when it is abnormal. In the figures, FIG. 3a is a side sectional view with a one-line contact conductive member attached, and FIG. 3b is a side sectional view with a two-line contact conductive member attached. In the figure, 1 is a printed board, 2 is a circuit component,
3 is an upper shield plate, 4 is a lower shield plate, 5 is a chassis, 6 is a single line contact conductive member, 7 is a two line contact conductive member, 8 is a conductive member, 9 is a conductive rubber, 10 is a rod shape , 11 is a conductive wire, 12 is a contact member, and 51 is a groove.

Claims (1)

[Claims for Utility Model Registration] (1) A grounding structure between a pair of shield plates 3 and 4 mounted on a printed board 1 and a chassis 5 is provided by a plurality of A grounding structure for a shield plate, characterized in that a groove 51 is formed, and an elastic conductive member 8 is interposed between the shield plate 4 and the chassis 5. (2) Utility model registration claim No. (1) characterized in that the conductive member 8 is formed of conductive rubber 9
The grounding structure of the shield plate described in . (3) The grounding of the shield plate according to claim (1) of the utility model registration, characterized in that the conductive member 8 is formed of a contact member 12 in which a conductive wire 11 is wound around a rod-shaped rubber 10. structure.