JPH0691421B2 - Micro capacity adjustment device for high frequency equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a capacitance adjusting device for a high-frequency device such as an electronic tuner that requires fine capacitance adjustment at a high frequency.

(Prior Art) A conventional high-frequency microcapacity adjusting device has a structure as shown in FIG.

In the figure, the oscillation circuit uses the resonance frequency of the inductance (L) and the capacitor (C), but there are variations in both the inductance and the capacitor, and due to variations in the position of parts, etc. Therefore, it is necessary to finely adjust the resonance frequency after the circuit has been constructed. In this case, the oscillating circuit is shielded by the partition plate 21 in both directions so that the oscillating frequency does not enter into other adjacent circuits.
The inductance (L) is composed of a U-shaped line 22 made of a copper plate, a brass plate or the like, and is soldered to the hole of the printed board 23. In the case of an electronic tuner, the capacitor (C) has the variable capacitance diode 24 soldered to the printed circuit board. Since there is a variation between the line 22 and the variable capacitance diode 24 and the oscillation frequency is set to the desired frequency, the line 22
A trimmer plate in which a flat plate made by pressing a copper plate, a brass plate, etc. is attached near the
By adjusting 25 in the direction of arrow A and moving it closer to or further from the line 22, the minute capacitance of this circuit was varied and tuning was performed.

(Problems to be Solved by the Invention) In the above-mentioned conventional method, a trimmer plate for adjusting a small capacity is required, and not only the number of parts increases, but also the number of steps for inserting the trimmer plate and soldering on the lower side. If the adjustment is repeated in the A direction at the time of attachment, there is a risk that cracks may occur from the root, and the component mounting area of the printed circuit board is narrowed only by the trimmer plate.

An object of the present invention is to eliminate the drawbacks of the prior art, integrate the trimmer plate into the partition plate of the frame, reduce the number of parts, and provide a highly reliable adjusting function.

(Means for Solving Problems) A microcapacity adjusting device for a high-frequency device according to the present invention comprises a partition plate or a shield plate that is bent substantially at a right angle from a part of the lower side, and the microcapacity is adjusted on a plane bent at a right angle. A substantially U-shaped trimmer plate that is movable for this purpose, and is fixed to one partition plate or shield plate that projects from the tip of this trimmer plate and is adjacent to or opposite to the partition plate or shield plate by soldering, etc. And a holding portion to be formed.

(Operation) With the above configuration, the present invention can eliminate the need for a single trimmer plate, and can prevent cracks and damages at the base of the trimmer plate even when performing harsh capacity adjustment work.

(Embodiment) An embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view of the minute capacity adjusting device of the present invention. In the figure, the oscillation circuit section is shielded by a partition plate such as an iron plate or shield plates 1, 2, 3 and 4 in each direction, and the line 5 that constitutes the inductance section of the oscillation circuit and the capacitor component The variable capacitance diode 6, other resistors, capacitors, transistors, etc. are soldered. Since there is a case where the desired oscillation frequency cannot be set due to variations in mounting and the like of each component that constitutes such an oscillator circuit, the earth potential of the divider circuit should be set close to the line 5 so that the oscillator circuit It has been found that fine tuning of the impedance can be done,
As its fine-capacity adjusting structure, the holding portion 7 is cut and raised from the lower side 2a of the partition plate or the shield plate 2 in the direction perpendicular to the line 5, and is bent at a right angle to the left in FIG. 1 to face the lower side of the line 5. From this position, the U-shaped trimmer plate 8 having the same shape as the line 5 is made to face the line 5 substantially in parallel, and the tip of the trimmer plate 8 is bent further at a right angle (downward right direction in FIG. 1) to form a partition plate. 3, the holding portion 9 of the trimmer plate 8 bent further to the left at a right angle and the partition plate 3 are electrically and mechanically connected by soldering or the like. When the upper portion 10 of the trimmer plate 8 configured as described above is adjusted in the direction of the arrow A with tweezers or an appropriate jig, the trimmer plate 8 is movable with the plane portions of the holding portions 7 and 11 formed on the lower side as fulcrums. Therefore, even if the trimmer plate 8 is severely repeatedly adjusted in the A direction, since the holding portions 7 and 11 are not directly soldered to the printed circuit board, a large stress is hard to be applied.
As shown in the figure, it has an integral structure with the partition plate or the shield plate 2, and since the holding portion 9 is joined to the partition plate or the shield plate 3 on a wide surface and soldered, the holding force is high, and any of the trimmer plates 8 It does not cut the part of, and is very easy to handle when adjusting the minute volume, and has high reliability in strength.

Although this embodiment has been described by using the oscillation circuit of the electronic tuner, it can be sufficiently used in the input tuning circuit of the electronic tuner, the interstage circuit, etc., and the same effect can be obtained.

(Effect of the invention) According to the present invention, the trimmer plate for adjusting the small capacity of the high-frequency device is constructed by using a part of the frame partition plate, so that the trimmer plate is manufactured separately, and is inserted into the printed board and soldered. Since it is not necessary to do so, the cost of parts is easy, the number of mounting steps is reduced, and the tip of the trimmer plate formed by bending the partition plate or shield plate is fixed to another partition plate or shield plate. Since it is held by the section, it is very easy to adjust, and even if it is repeatedly adjusted severely, it is not cut or displaced, and it is possible to provide a highly reliable microcapacity device.

[Brief description of drawings]

FIG. 1 is a perspective view of a micro-capacity adjusting device for high-frequency equipment according to an embodiment of the present invention, FIG. 2 is a configuration diagram of a trimmer plate used in the present invention, and FIG. 3 is a perspective view of a conventional micro-capacity adjusting device. Is. 1,2,3,4 …… partition plate or shield plate, 5 …… line,
6 ... Variable capacitance diode, 7,9,11 ... Trimmer plate holder, 8 ... Trimmer plate, 10 ... Trimmer plate upper part.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ari Isao, 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Bibliography 61-18635 (JP, U) 61793 (JP, U) Actual development Sho 56-114120 (JP, U)

Claims (1)

[Claims] 1. A substantially U-shaped trimmer plate which is bent at a right angle from a part of the lower side of a partition plate or a shield plate and is movable on the flat surface bent at a right angle for fine capacity adjustment, and this trimmer plate. Of a high-frequency device, characterized in that a holding portion fixed to one partition plate or shield plate adjacent to or facing the partition plate or shield plate by soldering or the like is formed so as to project from the tip of the partition plate or shield plate. Capacity adjustment device.