JPS6144421Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a capacitor, and in particular, to an improved structure of a capacitor that is compact and has a large capacity.

Normally, a capacitor has opposing electrodes each having a single plane on both sides of a dielectric material in the form of a disc or square plate, and the opposing areas of the front and back electrodes are used as a means for obtaining capacitance. There is a limit to the capacitance that can be acquired. In order to improve this problem, a method as shown in FIG. 1 has been proposed.

FIG. 1 is a perspective view of a capacitor as an interesting prior art to this invention. The capacitor shown here includes a cylindrical dielectric 1 with an oval cross section, and electrodes 2 and 3 are provided on the inner and outer cylindrical surfaces of the dielectric 1, respectively.
is formed. Lead wires 4 and 5 are connected to each electrode 2 and 3 by soldering, respectively. Such a configuration has the advantage that the entire circumference of the dielectric 1 as a single solid body can be used as a portion facing the electrode, so that the acquired capacitance can be increased.

However, the desire of those skilled in the art to develop capacitors that are smaller and larger in capacity is limitless, and a capacitor that can be made smaller and larger in capacity is desired.

Therefore, the main purpose of this invention is to provide a capacitor structure that can be made smaller and have a larger capacity.

In summary, this invention consists of at least one set of a plate-shaped dielectric material, for example, a combination of a portion bent in one direction and a portion bent in the other direction so that the cross-sectional shape is S-shaped. The entire outer surface is bent so that it has a cylindrical shape, with bends in both directions.
and at least one bent portion in one direction and at least one bent portion in the other direction both constitute respective portions of the cylindrical outer surface profile, whereby the plate A part of the plate-shaped dielectric crosses the space formed inside the cylindrical part at least once, and both of the first and second electrodes formed on each surface of the plate-shaped dielectric cross the space formed inside the cylindrical part at least once. It is configured to appear on each portion of the outwardly facing surface of the cylindrical outer contour.

Other objects and features of this invention will become clearer from the detailed description given below with reference to the drawings.

FIG. 2 is a perspective view of an embodiment of this invention.
Referring to FIG. 2, a first electrode 7 and a second electrode 8 are formed on each surface of the dielectric 6 to face each other. Of course, no electrode is formed on the surface extending in the thickness direction of the plate-shaped dielectric 6.
This plate-shaped dielectric 6 is bent so that its outer surface outline is cylindrical as a whole, and a part 6a of the dielectric 6 crosses a space formed inside this cylindrical part, and the first and the second electrodes 7, 8 are characterized in that they both appear on each part of the outwardly facing surface of the cylindrical external contour. Such characteristics are realized when the plate-shaped dielectric 6 is shaped according to the following rules.

That is, a portion 6b bent in one direction and a portion 6c bent in the other direction (opposite to the one direction)
The portion 6b is bent so that the overall outer surface contour forms a cylindrical shape while having at least one set of bidirectionally bent portions in combination with at least one portion 6b bent in one direction and at least one portion 6b bent in the other direction. This is when the plate-shaped dielectric 6 is shaped so that both the portion 6c bent in the direction constitutes each part of the cylindrical outer surface contour. In this embodiment, a dielectric 6 bent so that its cross-sectional shape has an S-shape is shown as one type that follows the above-mentioned law.

Electrodes 7 and 8 formed on each surface of the dielectric 6 described above
Lead wires 9 and 10 are connected to the terminals by soldering, respectively. Note that the lead wires 9 and 10 are arranged inside a cylinder formed by the dielectric 6.

FIG. 3 is a perspective view of another embodiment of this invention. In FIG. 3, parts corresponding to those shown in FIG. 2 are given the same reference numerals.

Referring to FIG. 3, the plate-shaped dielectric 6 is bent so that its cross-sectional shape is S-shaped, although in a different manner from that shown in FIG. Therefore, as in the case of FIG. 2, a portion 6a that intersects the cylindrical portion, a portion 6b that is bent in one direction,
and a portion 6c bent in the other direction. Therefore, when the cylindrical outer surface contour is formed by the bent dielectric 6, both the portion 6b bent in one direction and the portion 6c bent in the other direction are shaped like this cylindrical shape. The first electrode 7 and the second electrode 8
appear on each portion of the outwardly facing surface of the cylindrical external contour. Lead wires 9 and 10 are then connected to the first and second electrodes 7 and 8 by soldering, respectively. The lead wires 9 and 10 are arranged inside a cylinder formed by the plate-shaped dielectric 6.

FIG. 4 is a perspective view of still another embodiment of this invention. 4 is similar to that shown in FIG. 2 except for the following points. That is, the lead wires 9 and 10 are placed outside the tube formed by the dielectric 6 and connected by soldering. This soldering structure of the lead wires 9 and 10 requires simpler work and has improved reliability compared to the case where the lead wires 9 and 10 are arranged inside the cylinder as shown in Fig. 2. do. Thus, it is a very advantageous feature provided by this invention that both of the two leads 9, 10 can be connected by soldering on the outside. That is, in the prior art shown in FIG. 1, since one electrode 2 is not exposed to the outside, one lead wire 4 must necessarily be placed inside.

FIG. 5 is a perspective view of still another embodiment of this invention. 5 is similar to that shown in FIG. 3 except for the following points. That is, the lead wires 9 and 10 are placed outside the tube formed by the dielectric 6 and soldered. The advantages obtained by this embodiment are the same as those in FIG.

Figures 6 to 8 and Figures 9 to 11
The figures are illustrative cross-sectional views for explaining a method of manufacturing the dielectric 6 and electrodes 7, 8 shown in FIGS. 2 and 4, and 3 and 5, respectively. In addition, Fig. 6, Fig. 7, Fig. 8, and Fig. 9
10 and 11 each show the same process, and will be described with reference to both of them at the same time.

With reference to FIGS. 6 and 9, the dielectric 6 is
For example, it is formed from porcelain. This dielectric 6 is
For example, it is extruded in its raw form and prepared in a long length having a predetermined cross-sectional shape. This is fired and sintered as it is.

Next, electroless plating is performed to form nickel or copper films for electrodes 7 and 8, as shown in FIGS. 7 and 10, respectively. At this time, the metal film 11 is formed on the entire circumferential surface of the dielectric 6. The dielectric body 6 shown in FIGS. 6 and 7 and in FIGS. 9 and 10 has a portion 12 that projects outwardly from the cylindrical outer contour formed thereby. This protruding portion 12 was designed to make it easier to grind later, and in the next process, the line 13
This portion 12 is ground along.

Referring to FIGS. 8 and 11, after the above-mentioned grinding, the metal film 11 is removed from the plate-shaped dielectric 6.
Electrically isolated electrodes 7 and 8 are formed on each surface of the substrate. Either before or after this step, or at the same time, the structure including the elongated dielectric 6 is cut to form a chip-shaped structure including the dielectric 6 and electrodes 7 and 8 as shown in FIGS. 2 to 5. It is said that When using the manufacturing process as described above, the dimension H shown in FIGS. 2 and 3 can be easily changed, so any value of capacitance can be obtained by adjusting this dimension H. be able to.

Incidentally, although the capacitors shown in FIGS. 2 to 5 are sometimes used bare, they may also be dipped in resin.

As described above, according to this invention, it is possible to obtain a larger area facing the electrodes relative to the volume occupied by the entirety of one solid dielectric. For example, if the projected area is the same, the electrode facing area can be two to three times larger than that of a conventional conventional capacitor, and the capacitance can be increased two to three times. Furthermore, compared to the prior art shown in FIG. 1, the portion 6a that crosses the inside of the cylindrical space is increased, so it can be expected that the capacitance will increase accordingly.
Further, as shown in FIGS. 4 and 5, it is possible to arrange the lead wires 9 and 10 on the outside,
Therefore, it is possible to simplify the soldering work and improve the reliability of electrical connection. Furthermore, the second
By standardizing the dimension a as shown in FIG. 3 and FIG. 3, the distance between the lead wires 9 and 10 can be made constant.

In the above-mentioned embodiment, as a type of bending shaping of a plate-shaped dielectric material, the cross-sectional shape is S-shaped. However, the present invention is not limited to this, and for example, A plurality of parts 6a may be formed for one cylinder, and furthermore, it has a plurality of sets of bidirectionally bent parts consisting of a combination of a part 6b bent in one direction and a part 6c bent in the other direction. You can.

In addition, the dielectric material constituting the capacitor of this invention is not limited to ordinary porcelain; for example, grain-boundary insulated semiconductor porcelain can be used, and this invention can be used to develop grain-boundary insulated semiconductor porcelain capacitors with higher capacitance. can also be applied advantageously.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a capacitor as an interesting prior art to this invention. FIG. 2 is a perspective view of an embodiment of this invention. 3, 4 and 5 are perspective views of other embodiments of this invention, respectively. 6 to 8 and 9 to 11 show the dielectric 6 and electrodes 7 and 8 shown in FIGS. 2 and 4 and FIGS. 3 and 5, respectively.
FIG. 2 is an illustrative cross-sectional view for explaining the manufacturing method of the part. In the figure, 6 is a dielectric, 6a is a crossing part,
6b is a portion bent in one direction, 6c is a portion bent in the other direction, 7 is a first electrode, and 8 is a second electrode.

Claims (1)

[Claims for Utility Model Registration] (1) A plate-shaped dielectric body having first and second electrodes facing each other formed on each surface, the plate-shaped dielectric body being bent in one direction. and a portion bent in the other direction, the entire outer surface contour is bent in a cylindrical shape while having at least one set of bidirectional bending portions, and at least one bent in the one direction. Both the portion bent in the other direction and the at least one portion bent in the other direction constitute respective portions of the outer surface contour of the cylindrical shape, whereby a portion of the plate-shaped dielectric body is bent in the cylindrical shape. a capacitor configured to traverse a space formed inside the section at least once and such that both said first and second electrodes each appear on a respective portion of an outwardly facing surface of said cylindrical outer surface contour; . (2) The capacitor according to claim 1, wherein the plate-shaped dielectric is bent so that its cross-sectional shape is S-shaped. (3) The capacitor according to claim 1 or 2, wherein the dielectric material is made of porcelain. (4) The capacitor according to claim 1 or 2, wherein the dielectric is made of grain-boundary insulated semiconductor porcelain.