JPH0247896A - Connection structure of high-frequency circuit board - Google Patents

Abstract

PURPOSE:To heighten a shielding effect while making high integration possible by holding all side parts of a shielding plate between a shielding cover and a second high frequency circuit board while making its tip to contact with a gland pattern of a first high frequency circuit board. CONSTITUTION:A hole is opened in the central part of a first high frequency circuit board 1, while gland patterns 21 are formed on a peripheral positions of the upper surface of a second high frequency circuit substrate 2 while the gland patterns are formed also on the peripheral part of the underside. Further, a shield cover 3 consisting of a conductive member of a metal or the like is formed in the shape of a reversed container having inside projection pieces 31 on its four corners. A shield plate 5 is interposed inside the shield cover 3. All sides 51 of the shield plate 5 are held between the shield cover 3 and a second high frequency circuit board 2, while putting the shield cover 3 and the gland pattern 21 of the second high frequency circuit board 2 on all side part 51 for making them to electrically contact so as to heighten a shield effect.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a connection structure for connecting two high frequency circuit boards and shielding the high frequency portion.

[Conventional technology]

Conventionally, as a structure for connecting high-frequency circuit boards of different dimensions and shielding the high-frequency parts, the structures shown in Figs. 4 and 5 have been proposed.
The structure shown in the figure is adopted.

This structure includes a first high frequency circuit board 1 as shown in FIG.
A second high-frequency circuit board 2 is mounted thereon, and the high-frequency portion of the second high-frequency circuit board 2 is shielded by a shield cover 3. In this structure, as shown in FIG. 5(a) and FIG. 5(b), respectively, the cross section taken along the line B-B and the cross-section taken along the line C-C in FIG. are provided, and the first and second high-frequency circuit boards 1.2 and the shield cover 3 are integrally fixed on the inner protruding piece 31 with screws 4, whereby each board 1.2 is integrally fixed with screws 4.
The configuration is such that the two ground patterns are connected to each other and the shield cover 3 is connected to this ground pattern.

[Problem to be solved by the invention]

In the conventional connection structure described above, each board 1, 2 and the shield cover 3 are connected to the screws 4 at the four corners of the shield cover 3.
However, at the intermediate edge, each board 1.2 and each edge of the shield cover 3 simply contact each other, as shown in FIG. 5(b). For this reason, there is a problem that the connectivity at these side portions is reduced and the shielding effect is likely to be reduced.

In order to improve this, measures must be taken to provide a wide area ground pattern section at the contact area of each board 1, 2 and the shield cover 3, or to apply solder to the contact area, and furthermore, the screw 4.
Countermeasures are being taken, such as increasing the number of screws and fixing screws also at the middle side.

However, with this measure, the dead space of the circuit board increases due to the provision of the ground pattern, which is disadvantageous to high integration. Further, applying solder or increasing the number of screws causes the problem that the dead space increases and the number of work steps increases, reducing work efficiency.

The present invention solves the above-mentioned problems, has a high shielding effect,
Moreover, it is an object of the present invention to provide a connection structure for a high frequency circuit board that is advantageous for high integration.

[Means to solve the problem]

The high frequency circuit board connection structure of the present invention includes a first high frequency circuit board, a second high frequency circuit board mounted on the first high frequency circuit board, and a first high frequency circuit board that is placed on the second high frequency circuit board and that A shield cover is fastened and fixed to the first and second high-frequency circuit boards by screws passing through the boards, and a metal shield plate is inserted between the shield cover and the second high-frequency circuit board. The shield plate has four sides bent into a step-like shape, and the four sides are arranged so as to be sandwiched between the shield cover and the second high-frequency circuit board, and the tips of the four sides are bent. is configured to be brought into contact with a ground pattern provided on the first high frequency circuit board.

[Effect]

In the above-described configuration, the four sides of the shield plate are sandwiched between the shield cover and the second high-frequency circuit board, thereby improving the contact between them and enhancing the shielding effect. By bringing the tip into contact with the ground pattern of the first high frequency circuit board, mutual ground contact between the first and second high frequency circuit boards is also improved.

[Example] Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a partially cutaway perspective view of an embodiment of the present invention, and FIG. 2 is a sectional view taken along line A--A. In these figures, ■ is a first high-frequency circuit board with relatively large dimensions, with a hole 11 in the center and a hole 1 in the top surface.
A ground pattern 12 is formed at a peripheral position of 1.

Further, 2 is a second high-frequency circuit board having smaller dimensions, and a ground pattern 21 is formed on the periphery of the upper surface, and a ground pattern 22 is also formed on the periphery of the lower surface, although not shown. is forming. Furthermore, 3 is a shield cover made of a conductive member such as metal, which is formed in the shape of an amusement machine, and has inner protruding pieces 31 at its four corners. This shield cover 3 is placed over the second high-frequency circuit board 2 mounted on the first high-frequency circuit board 1, and the first and second high-frequency circuits are placed on the inner protrusions 31 at the four corners. It is fastened and fixed by screws 4 passing through the substrate 1.2.

Here, a shield plate 5 shown in FIG. 3 is inserted inside the shield cover 3. This shield plate 5 is made by punching and bending a metal plate with some spring properties to form a box-like shape approximately similar to the shield cover 3.Furthermore, the four corners are removed, and the four sides 51 are shaped into a stepped shape. The four sides 51 are bent and protrude toward the periphery and downward.

Then, this shield plate 5 is inserted between the shield cover 3 and the second high-frequency circuit board 2, and the four sides 51 are sandwiched between the four sides of the shield cover 3 and the second high-frequency circuit board 2. The screws 4 are used for fastening.

According to this configuration, the four sides 51 of the shield plate 5 are sandwiched between the shield cover 3 and the second high frequency circuit board 2, so that the shield cover 3 and the second high frequency circuit board
The shielding effect can be enhanced by placing the ground pattern 21 on the four sides 51 and electrically contacting the ground pattern 21.

Further, the lower tips of the four sides 51 also come into contact with the ground pattern 12 of the first high frequency circuit board 1, and
The ground contact between each of the high frequency circuit boards 1 and 2 is also made good.

Therefore, even if the screws 4 are fastened only to the four corners of the shield cover 3, good ground contact can be ensured in the periphery, and the first and second high frequency circuit boards 1
, 2 as well as between the second high frequency circuit board 2 and the shield cover 3.

This eliminates the need to take measures such as enlarging the ground pattern, soldering, and even increasing the number of screws, making it possible to achieve high integration and prevent a decrease in work efficiency.

〔Effect of the invention〕

As explained above, in the present invention, a shield plate is inserted between a shield cover and a second high-frequency circuit board, and the four sides of this shield plate are sandwiched between the shield cover and the second high-frequency circuit board. , and its tip is in contact with the ground pattern of the first high-frequency circuit board, thereby increasing the shielding effect between the shield cover and the second high-frequency circuit board, and increasing the shielding effect between the first and second high-frequency circuit boards. It also improves mutual ground contact and improves the shielding effect. In addition, a sufficient shielding effect can be obtained by simply tightening the shield cover at the four corners, so there is no need to enlarge the ground pattern, solder, or increase the number of screws.
It also has the effect of improving work efficiency.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway perspective view of an embodiment of the present invention, Fig. 2 is a longitudinal cross-sectional view taken along line A-A in Fig. 1, Fig. 3 is a perspective view of a shield plate, and Fig. 4 is a conventional FIGS. 5(a) and 5(b) are vertical cross-sectional views taken along line B-B and line C-C in FIG. 4, respectively. DESCRIPTION OF SYMBOLS 1... First high frequency circuit board, 2... Second high frequency circuit board, 3... Shield cover, 4... Screw, 5
... Shield plate, 11 ... Hole, 12 ... Ground pattern, 21 ... Ground pattern, 31 ... Inner protrusion piece, 51 ... Four sides. Figure 5

Claims (1)

[Claims] 1. A first high frequency circuit board and a second high frequency circuit board mounted thereon.
a high-frequency circuit board, a shield cover placed over the second high-frequency circuit board and fastened and fixed to the first and second high-frequency circuit boards at its four corners by screws passing through the first and second high-frequency circuit boards; and the shield. A metal shield plate is inserted between the cover and the second high-frequency circuit board, and the four sides of the shield plate are bent into a step shape, and the four sides are connected to the shield cover and the second high-frequency circuit board. arranged so as to be sandwiched between the high frequency circuit board of
A connection structure for a high frequency circuit board, characterized in that the tips of the four sides are brought into contact with a ground pattern provided on the first high frequency circuit board.