JPH0897575A - High-frequency circuit mounting structure and its manufacture - Google Patents

Abstract

PURPOSE: To provide a technical means by which different kinds of oscillation circuit units can be protected on printed wiring boards of the same design by making the printed wiring boards themselves to absorb shocks and vibrations from the outside without using any special parts. CONSTITUTION: In a high-frequency circuit mounting structure which is fitted to a printed wiring board 4 provided with a plurality of long holes near an oscillation circuit 3 unit fitting section, connecting sections 11 formed between each long hole of the board 4 are made thin-walled. The areas of the long holes are enlarged by fracturing the connecting sections 11 between each long hole of the wiring board 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency circuit mounting structure in which an oscillator circuit unit is mounted on a printed wiring board, and more particularly to a high-frequency circuit that absorbs external shocks and vibrations and suppresses fluctuations in the oscillation frequency of the oscillator circuit unit. The present invention relates to a mounting structure and a manufacturing method thereof.

[0002]

2. Description of the Related Art In a high-frequency circuit device having an oscillation circuit, it is necessary to electromagnetically shield the oscillation circuit. Therefore, the oscillation circuit is usually housed in a shield case, and further covered with a shield cover to form an independent oscillation circuit unit. Configure
It has been practiced to mount the oscillation circuit unit on a printed wiring board on which other electronic circuit components are mounted to form one high-frequency circuit.

However, when an external shock or vibration is applied to the oscillation circuit unit housed in the shield case via the printed wiring board, the components constituting the oscillation circuit, for example, the printed wiring board are distorted to cause the circuit. In some cases, the distribution constant of the element changes and the oscillation frequency changes, which may be a fatal defect in the high-frequency circuit device. Therefore, conventionally, a shock absorbing material such as silicon rubber is inserted between the oscillation circuit unit and the printed wiring board to absorb the shock and the vibration so that the external impact and the vibration are not applied to the oscillation circuit unit. . Hereinafter, this conventional structure will be described with reference to the drawings.

As shown in FIG. 4, an oscillation circuit (not shown)
Is housed in a shield case 1, covered with a shield cover 2 to form an oscillation circuit unit 3, and attached to a printed wiring board 4 via a silicon rubber plate 5. Further, the power supply is supplied through a looped lead wire 6 and a feedthrough capacitor 7 so that the shock and vibration from the printed wiring board 4 are not directly transmitted, and the oscillation output is taken out by a flexible output cable 8. . Further, the resonance frequency is lowered by increasing the weight of the shield case 1.

On the other hand, as a structure for protecting such an oscillation circuit unit from external vibration, the actual construction of Sho 63-14583
In Japanese Patent No. 5 publication, there is a support base 9 made by die casting or the like on the lower surface of the printed wiring board 4 supporting the oscillation circuit unit 3, as shown in FIG. There is disclosed a configuration in which vibration is absorbed by an elongated hole 10 provided in the printed wiring board 4 between the outer periphery of the oscillation circuit unit 3 and the support base 9.

[0006]

As described above, a cushioning material such as silicon rubber is inserted between the oscillation circuit unit and the printed wiring board in order to protect the oscillation circuit unit from external impacts and vibrations. When the configuration is adopted, a cushioning material such as silicone rubber is required, and there is a problem that the manufacturing cost increases because it takes a long time to apply and dry the adhesive in the bonding step. On the other hand, in the configuration using the support base created by die casting or the like, an expensive support base is required, and the size and arrangement of the optimal long holes differ depending on the size and weight of the oscillation circuit unit and the support base. Printed wiring boards have to be created for each product type, which causes a problem of increased manufacturing cost and complicated parts management.

In order to solve the above problems, an object of the present invention is to absorb external shocks and vibrations by the printed wiring board itself without using any special parts, and to use the printed wiring board of the same design. , To provide a technical means capable of protecting different types of oscillator circuit units.

[0008]

According to the present invention, there is provided an oscillation circuit unit, and a printed wiring board having a plurality of elongated holes around a mounting portion of the oscillator circuit unit and a thin connecting portion between the elongated holes. A high-frequency circuit mounting structure comprising Also,
It is preferable that the elongated hole is formed in the mounting portion of the printed circuit board on which the oscillator circuit unit is attached and the outer periphery thereof.
Further, in a printed circuit board having a plurality of elongated holes around the mounting portion of the oscillator circuit unit and having a thinned connecting portion between the elongated holes, the high frequency circuit for breaking the connecting portion to increase the area of the elongated hole. A method of manufacturing a mounting structure is provided.

[0009]

According to the above structure, since the printed wiring board having the plurality of elongated holes with thin connecting portions is formed around the oscillation circuit unit mounting portion, external impact or vibration is prevented.
It is absorbed by the long hole and the thin connecting portion and does not transmit to the oscillation circuit unit. Therefore, only the printed wiring board,
Since the oscillator circuit unit is protected against external shocks and vibrations, special parts such as silicon rubber and a support stand are not required, and extra man-hours are not required, so that the manufacturing cost can be reduced.

Further, the area of the elongated hole can be enlarged by breaking the thin connecting portion as required, whereby the arrangement of the elongated hole optimum for the oscillation circuit units of different sizes and weights can be achieved. And size can be freely formed. Therefore, it is not necessary to prepare a printed wiring board for each product type, which simplifies component management.

By forming a plurality of elongated holes in the oscillation circuit unit mounting portion and the inner periphery thereof, the shock and vibration absorption characteristics of the printed wiring board can be further improved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. The same parts as those of the conventional example are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 1, the high frequency circuit mounting structure of this embodiment has a plurality of elongated holes 1 each having a thin connecting portion 11 around the mounting portion of the oscillation circuit unit 3 of the printed wiring board 4.
2, the power source is supplied through the looped lead wire 6 and feedthrough capacitor 7 so that the shock and vibration from the printed wiring board 4 are not directly transmitted, as in the conventional example, and the oscillation output is flexible. It is taken out by the output cable 8 of.

When an external impact or vibration is applied to the printed wiring board of the high-frequency circuit mounting structure constructed as described above, the impact or vibration propagates through the printed wiring board and spreads throughout. However, at the oscillator circuit unit mounting part,
The transmission of vibration is cut off by a plurality of elongated holes formed around it, and the vibration is absorbed because the connecting portion of the elongated holes is thin. Therefore, almost no vibration or shock is transmitted to the oscillation circuit unit, and it is possible to prevent the oscillation frequency from fluctuating due to the change in the distributed constant of the built-in circuit.

Further, when the size and weight of the oscillation circuit unit differ depending on the product type, the optimal area and arrangement of the long holes for preventing the transmission of vibrations change, but in this case, the connecting portion of the thin long holes is broken. By doing so, the area of the long holes can be expanded and the shape of the long holes can be changed, so that the optimum area and arrangement of the long holes can be created without preparing a printed wiring board of another design.

The example in which a plurality of long holes are formed in a row on the printed wiring board 4 on the outer periphery of the mounting portion of the oscillator circuit unit 3 has been described above, but the present invention is not limited to this example, and the second embodiment of the present invention is as follows. As shown in FIG. 2, if the printed wiring board 4 is formed with a plurality of elongated holes 12 and 13 arranged in two rows and in a zigzag pattern, vibration that is not completely absorbed by the thin connecting portion 11 in the first row is generated. Since it can be cut off by the elongated holes 13 in the second row, it is possible to completely prevent the transmission of vibration and impact to the oscillation circuit unit 3.

In the third embodiment of the present invention, as shown in FIG. 3, the connecting portion 1 is also attached to the mounting portion of the oscillator circuit unit 3, that is, the mounting surface of the oscillator circuit unit to the printed wiring board 4.
4 is a high-frequency circuit mounting structure having a plurality of elongated holes 15 having a thin wall. According to this embodiment, not only the thin connecting portion 14 can be partially broken to change the area and the arrangement of the elongated holes 15, but also the entire connecting portion 14 can be broken to remove the mounting portion. A part of the inner printed wiring board 4 can be removed. In this way, it is possible to greatly change the resonance frequency of the mounting portion and prevent the transmission of vibration.

[0018]

According to the present invention, since a printed wiring board having a plurality of elongated holes having thin connecting portions in the longitudinal direction is formed around the oscillation circuit unit mounting portion, external impact or vibration is prevented. It is absorbed by the long hole and the thin connecting portion and does not transmit to the oscillation circuit unit. Therefore, because the oscillator circuit unit is protected against external shocks and vibrations only with the printed wiring board, special parts such as silicon rubber and a support stand are not required, and the number of installation steps is also unnecessary, reducing manufacturing costs. it can.

Further, by breaking the thin-walled connecting portion as necessary, the area of the long holes is enlarged, so that the optimum arrangement and size of the long holes can be obtained for the oscillation circuit units of different sizes and weights. Can be freely formed. Therefore, it is not necessary to prepare a printed wiring board for each product type, which simplifies component management.

By providing a plurality of elongated holes on the outer circumference and inner circumference of the oscillator circuit unit mounting portion, the shock and vibration absorption characteristics of the printed wiring board can be further improved.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of a high-frequency circuit mounting structure of the present invention.

FIG. 2 is a plan view of a printed wiring board according to a second embodiment of the present invention.

FIG. 3 is a plan view of a printed wiring board according to a third embodiment of the present invention.

FIG. 4 is a perspective view of a conventional high-frequency circuit mounting structure.

FIG. 5 is a perspective view of another conventional high-frequency circuit mounting structure.

[Explanation of symbols]

 3 Oscillation circuit unit 4 Printed wiring board 6 Lead wire 8 Output cable 11,14 Connecting part 12,13,15 Long hole

Claims (3)

[Claims] 1. A high-frequency circuit mounting structure comprising: an oscillation circuit unit; and a printed wiring board having a plurality of elongated holes around a mounting portion of the oscillator circuit unit and a thin connecting portion between the elongated holes. 2. The high-frequency circuit mounting structure according to claim 1, wherein the elongated hole is formed in the mounting portion of the printed circuit board and the outer periphery thereof. 3. A printed wiring board having a plurality of elongated holes around an oscillation circuit unit mounting portion and having thinned connecting portions between the elongated holes, the connecting portion is broken to increase the area of the elongated hole. Method for manufacturing high-frequency circuit mounting structure.