JPS6124812B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a terminalless flat plate capacitor whose capacitance can be easily changed and which can be directly attached to a printed circuit board without using lead terminals.

A conventional capacitor has two lead terminals, and is attached by inserting the lead terminals into holes in a printed circuit board or the like. For this reason, attaching the lead terminals to the capacitor body requires complicated and troublesome work, and has the disadvantage of increasing the size of the structure. There is a drawback that holes must be provided. In addition, when changing the capacitance of a capacitor, the individual capacitors are connected individually using a soldering iron or the like, or are separated. Therefore, there are disadvantages in that capacity adjustment is extremely complicated and minute capacity adjustment is not possible. In addition, as a capacitor whose capacity can be changed,
There is a movable type so-called variable capacitor, but it has the drawbacks that it is difficult to manufacture because it has movable parts and the structure becomes bulky. Therefore, the present invention seeks to provide a variable capacitor that does not have the above-mentioned drawbacks.

This invention will be explained below.

The present invention relates to a terminalless flat plate capacitor, in which a plurality of elongated first conductive materials separated and aligned are disposed on one surface of a microscopic (approximately 1 cm square) and extremely thin (approximately 30 μ) rectangular mica film. At the same time, two elongated second conductive materials are disposed on the other surface of the mica film so as to intersect with the first conductive material, and the intersection of the first conductive material and the second conductive material is arranged. At least one part of the parts is connected by a through hole to form a mixed series and parallel capacitor circuit, and the overall capacitance of the capacitor circuit can be changed by cutting or partially peeling off the first conductive material. At the same time, each end of the second conductive material can be directly attached to a printed circuit board or the like as a terminal of a capacitor circuit.

First, the variable mica capacitor, which is the principle of this invention, will be explained with reference to FIGS. 1A to 1C.
Approximately 30cm thick and shaped into a square of approximately 1cm for a capacitor.
As shown in Figure A, the surface of the rectangular mica film 1 of μ is covered with four thin elongated conductive materials 2 to 5 (for example, conductive silver paste) solid-molded with powders of silver, copper, etc. are printed and printed at equal intervals using, for example, silk screen or roller printing. In addition, on the back side of the mica film 1, as shown in FIG. Conductive materials 6 and 7 are printed and baked in the same manner as described above. Incidentally, FIG. 1C shows the side view thereof. Thus, the overlapping portions of the conductive materials 2 to 5 facing each other with the mica film 1 in between and the conductive materials 6 and 7 form a capacitor, and the equivalent circuit when viewed from the ends A and B of the conductive materials 6 and 7 is as follows. It will look like Figure 2. That is, capacitor CI is made of conductive materials 2 and 7, and capacitor C2 is made of conductive material 2.
and 6, capacitor C3 by conductive materials 3 and 7, capacitor C4 by conductive materials 3 and 6, and capacitor C5 by conductive materials 4 and 7.
Accordingly, capacitor C6 is formed by conductive materials 4 and 6, capacitor C7 is formed by conductive materials 5 and 7, and capacitor C8 is formed by conductive materials 5 and 7, respectively. Thus, capacitors C1 and C2 are connected in series by conductive material 2, capacitors C3 and C4 are connected in series by conductive material 3, capacitors C5 and C6 are connected in series by conductive material 4, and capacitor C7 is connected in series by conductive material 4. and C8 are connected in series by the conductive material 5, and are connected in parallel, so the combined capacitor capacitance Cts between ends A and B is: Cts=C1・C2/C1+C2+C3・C4/C3+C4+C5・C6/ C5+C6+C7・C8/C7+C8...
...(1)

However, in the capacitor of the present invention, as shown in FIG. 3, a through hole 1 is provided at the intersection of the conductive material 2 and the conductive material 7 to electrically connect them.
At the same time as attaching 0, as shown in 11 and 12, cut or peel off the ends or part of the center of conductive materials 2 to 5 with a knife, glass pen, etc. to separate them into two or reduce the overlapping area. It has a structure that allows for Therefore, the capacitor C1 corresponding to the through hole 10 disappears, and the capacitance of the capacitor C4 decreases to C4A.
Capacitors C7 and C8 are disconnected. Thus, the equivalent circuit in this case is as shown in Figure 4, and the combined capacitor and capacitance Ct ₁ is Ct ₁ =C ₂ +C3・C4A/C3+C4A+C5・C6/
C5+C6……(2), and the capacitance of the capacitor changes. This is the same when the other conductive materials 2 to 5 are made through holes or peeled off by cutting, and the conductive materials once peeled off by cutting can be bonded again using an electric heating iron or the like.

In this way, when the conductive materials on the front and back sides are connected through a through hole, it becomes one capacitor, so a relatively large capacitance can be adjusted.If the conductive material is separated by cutting off the middle part, the two capacitors are disconnected. Therefore, a relatively moderate capacitance adjustment can be made, and when a part of the conductive material is cut and peeled off, an extremely minute capacitance adjustment can be made. Also,
When installing the capacitor on a printed circuit board, etc., the ends A and B (or B1) of the conductors (6, 7)
Since it is sufficient to directly solder the lead terminals, there is no need to provide holes for attaching lead terminals as in the conventional case, which is extremely convenient.

As described above, according to the mica capacitor of the present invention, the capacitance of the capacitor can be roughly adjusted by simple manual operations, and medium adjustment and fine adjustment are also possible, and there is no need to attach lead terminals. The manufacturing process is simplified and it becomes possible to attach it directly to a printed circuit board or the like.

In the above-described embodiment, the number of conductive materials 2 to 5 is four, but the number is arbitrary, and the sizes thereof do not need to be the same.

[Brief explanation of the drawing]

1A to 1C are a plan view, a bottom view, and a side view of an example of a capacitor for explaining the principle of this invention, FIG. 2 is an equivalent circuit diagram thereof, and FIG. 3 is an example of an embodiment of this invention. The plan view of the capacitor shown in FIG. 4 is an equivalent circuit diagram thereof. 1...mica film, 2-7...conductive material,
10... Through hole, 11, 12... Cutting peeling part.

Claims (1)

[Claims] 1 A plurality of elongated first conductive materials separated and aligned are disposed on one surface of a microscopic and ultrathin rectangular mica film, and the first conductive material is disposed on the other surface of the mica film. A second conductive material having an elongated shape equal to the length of the two mica films is disposed so as to intersect with the mica film, and at least one of the intersections of the first conductive material and the second conductive material is passed through the second conductive material. The first conductive material is connected by a hole to form a mixed series and parallel capacitor circuit, and the overall capacitance of the capacitor circuit can be changed by cutting or partially peeling off the first conductive material. 1. A terminal-less flat plate capacitor, characterized in that one end of each conductive material of No. 2 can be directly attached to a printed circuit board or the like as a terminal of the capacitor circuit.