JPS5953692B2 - magnetic circuit element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for forming electrodes of a magnetic circuit element, particularly for example, a varistor or a capacitor, and for connecting the formed electrodes and conductive terminals. This invention relates to a ceramic circuit element made using a conductive adhesive.

Conventionally, for example, in order to eliminate sparks in a micromotor, a method has been taken in which a ceramic circuit element is interposed between commutator pieces.

Although the present invention is not limited to the magnetic circuit element used for extinguishing sparks as described above, it is possible to efficiently form electrodes in the circuit element as described above and connect the electrodes to conductive terminals. The purpose is to obtain a magnetic circuit element.

That is, in the conventional magnetic circuit element used for extinguishing sparks as described above, electrodes are formed on the element, and at the same time, solder is applied to an external conductive terminal (or an end plate (in the present invention, both are referred to as a conductive terminal)). To facilitate finishing, the surface of the porcelain element is treated with metallicon.

In this case, metallicon treatment has the advantage of accurately controlling the electrode area and the distance between the electrodes.
On the other hand, metallization treatment is troublesome, and soldering to external conductive terminals may cause localized heating, which may result in cracking of the ceramic element.

In the present invention, for example, in the case of a ceramic element as shown in JP-A-48-86091, the varistor characteristics etc. can be controlled by the oxide film present in the contact area between the surface of the ceramic element and the electrode metal. Focusing on the fact that the surface area does not necessarily need to be large, we also focused on the fact that it can be bonded to external conductive terminals with conductive adhesives such as silver adhesive, carbon adhesive, and even silver paste. Depending on the material, connection to external terminals can be made at the same time as electrode formation.

This will be explained below with reference to the drawings. Figures 1A and B and Figure 2 each show an example of a conventional ceramic circuit element in which a ceramic element is treated with metallicon, and Figure 3A shows an example in which a conductive adhesive is applied to the surface of the ceramic element according to the present invention. , FIG. 3B shows an embodiment of the external conductive terminal, and FIG. 4 shows an embodiment of the present invention in which the ceramic element shown in FIG. 3A and the external conductive terminal shown in FIG. 3B are bonded together. .

Figures 1A and 1B show the front and back sides of a hollow disk-shaped ceramic element, in which 1 is the ceramic element, 2°3.4 is a metallicon surface, and the surfaces are separated from each other on the surface of the ceramic element 1. 5 represents a metallicon surface formed on the back surface of the ceramic element 1.

In this case, a variable resistor (varistor) or a capacitor is formed between the metallized contact surfaces 2 and 5, between the metallized contact surfaces 3 and 5, and between the metallic contact surfaces 4 and 5, respectively. For connection, each metallic contact surface and the external conductive terminal are finished by soldering.

FIG. 2 shows a conventional example of forming a varistor or capacitor on one surface of a ceramic element, in which 1 is a hollow disk-shaped ceramic element, 2. 3. 4 represents a metallicon surface formed on one surface of each hollow disk-shaped ceramic element.

That is, conventionally, in this type of ceramic circuit element, the surface of the ceramic element was subjected to metallization treatment for electrode formation and solder finishing.

In contrast, the present invention is configured to connect to an external conductive terminal using a conductive adhesive.

In FIG. 3A, 1 is a hollow disk-shaped ceramic element, 6, 7.
Reference numeral 8 indicates a conductive adhesive such as a silver adhesive or a carbon adhesive applied to the surface of the ceramic element according to the present invention, and in FIG. It shows.

In the case of the present invention, as shown in FIG. 3A, the conductive adhesive 6.
7. 8 is applied so as to cover a predetermined area of the surface of the ceramic element, and external conductive terminals 10, 1 as shown in FIG. 3B are formed.
1.12 is bonded to the insulating plate 9.

FIG. 4 shows an embodiment of the formed ceramic circuit element of the present invention, and the reference numerals in the figure correspond to those in FIGS. 3A and 3B.

That is, as shown in the figure, a ceramic element 1 whose bare surface, which has not been subjected to metallization treatment, is coated with a conductive adhesive 6,7°8 is stacked on an insulating plate 9 having external conductive terminals 10°11,12. The solvent in the adhesive is dispersed into the atmosphere to form a bond.

and adhesive 6. 7. The coating area 8 also becomes the area of the electrode formed on the ceramic element 1, and by selecting the area appropriately, a desired resistance value and capacitance value can be determined.

In the actual process, it is sufficient to place the surface of the porcelain element 1 and the surface shown in FIG. 3B facing each other and then place a limited amount of the adhesive between them.

As described above, according to the present invention, electrodes can be formed by simply sandwiching the conductive adhesive material after stacking the ceramic element 1 on the external conductive terminal, and bonding with the external conductive terminal becomes possible. It is much easier to manufacture than the conventional metallized circuit element which is processed with solder and finished with solder, and it is possible to obtain a ceramic circuit element whose electrical characteristics are comparable to those of the conventional circuit element.

It goes without saying that the adhesive referred to in this specification can also be used as a material generally used as a paint, as long as the desired contact strength is obtained.

[Brief explanation of the drawing]

Figures 1A and B and Figure 2 respectively show an example of a ceramic circuit element in which a ceramic element is treated with metallicon, and Figure 3A shows an example of a ceramic circuit element in which a conductive adhesive is applied to the surface of the ceramic element according to the present invention. Figure 3B is an example of the external conductive terminal, and Figure 4 is the third embodiment of the external conductive terminal.
3 shows an embodiment of the present invention in which the ceramic element shown in FIG. A and the external conductive terminal shown in FIG. 3B are bonded together. In the figure, 1 is a ceramic element, 6. 7. 8 is a conductive adhesive;
10, 11, and 12 indicate external conductive terminals.

Claims (1)

[Claims] 1. In a ceramic circuit element configured by conductively attaching a ceramic element to a conductive terminal, an insulating plate configured to support a hollow disc-shaped ceramic element, an external conductive terminal, and a support on the surface of the insulating plate. three external conductive terminals extending in the radial direction from each other, and a conductive adhesive interposed between the surface of the ceramic element and each of the external conductive terminals, the conductive adhesive directly contacting the external conductive terminals. A ceramic circuit element comprising an electrode for a ceramic element and mechanically bonding the ceramic element and the external conductive terminal.