JPH0229710Y2 - - Google Patents

Description

[Detailed description of the invention] Field of the invention This invention consists of a plurality of internal electrodes arranged in a stacked state with each other via a dielectric layer to form a capacitance, and a predetermined one of the internal electrodes. The present invention relates to a multilayer capacitor having a pair of external electrodes connected to each other and having folded electrodes for taking out capacitance, and particularly relates to a multilayer capacitor with improved withstand voltage.

Prior Art In a multilayer capacitor as shown in FIG. 1, 1a, 1b, 1c, 1d, and 1E are dielectric layers made of ceramic dielectric.
Internal electrodes 2a, 2 made of a paste conductor such as palladium, silver palladium, etc. are provided on b, 1c, 1d.
b, 2c, and 2d are provided. These dielectric layers 1a, 1b, 1c, 1d, and 1e are stacked in order, heated and pressurized to integrate them, and are fired to form the capacitor element 3. 4 and 5 are external electrodes formed by baking a conductor such as silver paste, and the external electrode 4 is connected to the internal electrodes 2b and 2d, and the external electrode 5 is connected to the internal electrode 2.
a and 2c, respectively.

By the way, this conventional multilayer capacitor has
Between the tip 4a of the folded electrode of the external electrode 4 and the tip of the internal electrode 2a, and between the tip 5a of the folded electrode of the external electrode 5 and the tip of the internal electrode 2d,
The drawback was that voltage breakdown was likely to occur. There are two reasons for this. One is that the polarities of the external electrode 4 and the internal electrode 2a, and the polarities of the external electrode 5 and the internal electrode 2d are different, which causes lines of electric force to concentrate in these parts. The other reason was that the tensile stress of the external electrodes 4 and 5 was likely to be concentrated in this area, and cracks were likely to occur.

Therefore, when trying to obtain a high-voltage product,
The dielectric layer had to be made thicker, which increased the overall size, and the thicker dielectric layer also led to a decrease in capacitance.

Purpose of the invention This invention was made to solve the above problems, and its purpose is to provide a multilayer capacitor with improved withstand voltage.

Summary of the invention To summarize this invention, the outermost internal electrode is
They extend from one and the other external electrode toward the other and one external electrode to a width greater than the width of the folded electrode of the external electrode, and are formed in a pair so that they are not connected to each other, and the outermost internal electrode and this A floating internal electrode that is not connected to the external electrode is formed between the internal electrode adjacent to the floating internal electrode, and the internal electrodes located inside the floating internal electrode have one end connected to a dielectric layer so as to form a parallel capacitance with each other. This is a multilayer capacitor that is formed to reach the edge of the

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the multilayer capacitor of this invention will be described with reference to the drawings.

FIG. 2 shows an example of a dielectric layer used in an embodiment of the multilayer capacitor of this invention, and FIG. 3 shows an embodiment of the multilayer capacitor of this invention.

First, dielectric layers 11a, 1 made of ceramic
1b, 11c, 11d, 11e, 11f, 11
g, 11h, and 11i are prepared, and each is provided with an internal electrode having the shape shown in FIG. The internal electrodes are provided by screen printing a conductor such as palladium paste. Internal electrodes 12a and 12 are provided on the dielectric layers 11a and 11h.
floating internal electrodes 12b and 12g are provided on the dielectric layers 11b and 11g, respectively. Dielectric layers 11c, 11d,
Internal electrodes 12c, 12d, 12e, 12, one end of which reaches the edge of the dielectric layer, are provided in 11e and 11f.
f are provided respectively. Note that the dielectric layer 11i
is a protective layer and no internal electrodes are provided. The dielectric layers provided with the internal electrodes are stacked in order in the direction shown in the figure, heated and pressurized to integrate, and then fired, thereby forming the capacitor element 13 as shown in FIG. be done.

Next, external electrodes 14 and 15 formed by baking a conductor such as silver paste are provided on both ends of this capacitor element 13, as shown in FIG. The external electrode 14 is the internal electrode 12a, 12d, 12f, 12
h, and the external electrode 15 is the internal electrode 12a', 12c,
12e and 12h', respectively.

In the multilayer capacitor of this invention thus formed, the inner electrodes 12a and 12h of the outermost layer extend from the outer electrode 14 to the outer electrode 15, and the inner electrodes 12a' and 12h' of the outermost layer extend from the outer electrode 15 to the outer electrode 15. Toward the electrode 14, the outer electrodes 14 and 1
The inner electrodes 12a and 12a' and the inner electrodes 12h and 12h' are formed in a pair shape such that the inner electrodes 12a and 12a' and the inner electrodes 12h and 12h' are not connected to each other. Furthermore, adjacent to these, external electrodes 14 and 15
Floating internal electrodes 12b and 12g are formed which are not connected to any of them. As described above, in the multilayer capacitor of this invention, the external electrode 14 and the outermost internal electrodes 12a and 12h have the same polarity, and the external electrode 15 and the outermost internal electrodes 12a' and 12h' have the same polarity. Therefore, lines of electric force may concentrate between the folded electrode and tip 14a of the external electrode 14 and the outermost layer internal electrode 12a, and between the folded electrode tip 14b of the external electrode 14 and the outermost layer internal electrode 12h. do not have. Similarly, lines of electric force are formed between the tip 15a of the folded electrode of the external electrode 15 and the inner electrode 12a' of the outermost layer, and between the tip 15b of the folded electrode of the outer electrode 15 and the inner electrode 12h' of the outermost layer. I can't concentrate. Therefore, the multilayer capacitor of this invention has improved withstand voltage compared to conventional capacitors.

Furthermore, in the multilayer capacitor of this invention, the floating internal electrode 12b connects the outermost layer internal electrode 12a and 1
2a′, floating internal electrode 12g
This shares the capacitance between the outermost internal electrodes 12h and 12h', and is useful for forming capacitance.
Furthermore, the electric field strength between the tip portions of the internal electrodes 12a, 12h' and the internal electrodes 12c, 12f is also
It can be reduced by the presence of 2b and 12g,
The withstand voltage can be improved.

The above is one embodiment of this invention, and it goes without saying that the design can be changed within a range that does not impair the spirit of the invention. For example, in this embodiment, nine dielectric layers are stacked, but the number of dielectric layers can be increased or decreased depending on the number of internal electrodes that are arbitrarily selected, and is not limited to this.

Effects of the invention As is clear from the above explanation, the multilayer capacitor of this invention has the inner electrodes on the outermost layer larger than the width of the folded electrodes of the outer electrodes and arranged in pairs, and adjacent to the inner electrodes. Because floating internal electrodes are formed, the withstand voltage is significantly improved compared to conventional products. Therefore, according to this invention, the advantages of the conventional multilayer capacitor such as small size and high capacity can be combined with the advantage of high withstand voltage.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing a conventional multilayer capacitor, and FIG. 2 is a plan view showing an example of a dielectric layer used in an embodiment of the multilayer capacitor of this invention.
FIG. 3 is a side sectional view showing an embodiment of the multilayer capacitor of this invention. 11a, 11b, 11c, 11d, 11e, 1
1f, 11g, 11h, 11i...dielectric layer, 1
2, 12a', 12c, 12d, 12e, 12f,
12h, 12h'...Internal electrode, 12b, 12g...
...Floating internal electrode, 13...Capacitor element, 1
4, 15...external electrode.

Claims (1)

[Claims for Utility Model Registration] A plurality of internal electrodes arranged in a stacked state with each other via dielectric layers to form capacitance, and a folded electrode connected to a predetermined one of the internal electrodes. In a multilayer capacitor having a pair of external electrodes for taking out capacitance, the outermost internal electrode of the internal electrodes has an outer electrode extending from one and the other external electrodes toward the other and one external electrode. The outer electrodes extend larger than the width of the folded electrodes and are formed in pairs so as not to be connected to each other, and between the inner electrodes in the outermost layer and the inner electrodes adjacent to the inner electrodes in the outermost layer. A floating internal electrode is formed that is not connected, and the internal electrode inside the floating internal electrode is
A multilayer capacitor characterized by being formed so that one end reaches the edge of a dielectric layer so as to form a parallel capacitance.