JP2567073B2 - Multilayer capacitor block - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a capacitor block for forming a delta connection circuit used in a power supply device or the like, and more particularly to a capacitor block using a multilayer capacitor.

[Conventional technology]

Conventionally, in the power supply circuit shown in FIG.
The third capacitors 1, 2 and 3 are used in a delta connection. Among the capacitors 1 to 3, the capacitor 1 is connected between the lines and the capacitors 2 and 3 are connected between the line and the ground potential, and both capacitors are inserted to perform the noise absorbing function.

These capacitors 1 to 3 are required to have high withstand voltage because they are used in a power supply circuit. Conventionally, when a multilayer capacitor is used as each of the capacitors 1 to 3 in configuring such a power supply circuit,
A separate capacitor element was prepared for each, and they were connected and used as shown in the figure.

[Technical problem to be solved by the invention]

As described above, in constructing the power supply circuit of FIG. 2, conventionally, each of the capacitors 1 to 3 is prepared as a separate component and connected and used on the substrate or the like. Therefore, a large mounting space is required and the mounting cost is high.

Therefore, it is an object of the present invention to provide a multilayer capacitor block having a structure capable of improving the mounting space and mounting efficiency of the capacitor portion in constructing a delta connection circuit and easily increasing the capacitance. is there.

[Means for solving technical problems]

The present invention is a multilayer capacitor block in which three capacitors used in a delta connection circuit are built in a state of being connected according to the delta connection circuit, and have the following configuration.

That is, in the sintered body made of dielectric ceramics,
A plurality of internal electrodes are arranged so as to overlap each other in the thickness direction via the dielectric ceramic layer. The plurality of internal electrodes constitute first to third internal electrode groups arranged in the thickness direction in order to form first to third multilayer capacitors in the thickness direction.

The internal electrode connected to one potential of the first and second internal electrode groups is led out to the first lead-out portion on the side surface of the sintered body. Further, the internal electrode connected to the other potential of the first internal electrode group and the internal electrode connected to one potential of the third internal electrode group are led out to the second lead portion on the side surface of the sintered body. ing. Furthermore, the internal electrode connected to the other potential of the second and third internal electrode groups is led out to the third lead-out portion on the side surface of the sintered body. In addition, one internal electrode group adjacent to each other in the thickness direction and the adjacent internal electrodes of the other internal electrode group are connected at the same potential, and a sintered body layer is provided between the internal electrodes connected to the same potential. Separated.

First to third external electrodes are provided to the first to third lead portions, respectively.

[Action]

The present invention is characterized by reducing the mounting space, improving the handling and mounting work by integrating the three capacitors forming the Delda connection circuit by a multilayer capacitor technology to form a multilayer capacitor block. To do.

That is, by arranging the first to third internal electrode groups in a single sintered body, the first to third multilayer capacitors are integrally formed. In addition, since the internal electrode group of each multilayer capacitor is led out to the first to third lead-out portions and connected to the first to third external electrodes, they are electrically connected to each other according to the delta connection circuit. It is said that it has been Therefore, by using the multilayer capacitor block of the present invention, a delta connection circuit can be immediately constructed.

Further, in the multilayer capacitor block of the present invention, among the first to third internal electrode groups, one internal electrode group adjacent in the thickness direction and the adjacent internal electrode of the other internal electrode group are connected to the same potential. Therefore, it is possible to reduce the crosstalk between the capacitors formed by the adjacent internal electrode groups. Moreover, since the internal electrodes connected to the same potential are separated by the sintered body layer, the dielectric strength is also increased.

[Explanation of Example]

The manufacturing process of one embodiment of the present invention will be described below with reference to the drawings to clarify the details of the structure. The present embodiment is a multilayer capacitor block that realizes the equivalent circuit shown in FIG.

First, as shown in FIG. 1, ceramic green sheets 11 to 24 made of a plurality of dielectric ceramics are prepared. As each of the ceramic green sheets 11 to 24 is required to have a high pressure resistance, a material having a high pressure resistance or a material having a relatively large thickness is used.

Notches 11a to 24a are formed in the respective ceramic green sheets 11 to 24, as shown in the drawing. Cutout 11a
Numerals 24a to 24a are provided for forming recesses described later in the obtained sintered body.

No electrode paste is applied on the ceramic green sheets 11, 15, 20, 24. That is, the ceramic green sheets 11 and 24 are laminated so that the internal electrodes are not exposed to the outer surface of the sintered body, while the ceramic green sheets 15 and 20 are adjacent to each other, which will be described later. This is because it is inserted to separate the capacitor part.

The ceramic green sheets 11 to 24 are inserted to form the first multilayer capacitor, and the electrode pastes 31, 32, and 33 are printed on the upper surfaces to form internal electrodes. Of these, electrode paste 31,33
Is the cutout 1 of the ceramic green sheets 12 and 14, respectively.
It is drawn out to the end edge portions 12b and 14b sandwiching 2a and 14a. On the other hand, the electrode paste 32 applied on the ceramic green sheet 13 is drawn out to the edge portion 13b on the other side sandwiching the notch 13a.

The electrode pastes 34 to 37 applied on the ceramic green sheets 16 to 19 are provided to form the internal electrodes of the second multilayer capacitor, respectively.

The electrode pastes 34 and 36 printed on the ceramic green sheets 16 and 18 are one edge portion 16 sandwiching the notches 16a and 18a.
b, 18b. In addition, the electrode pastes 35 and 37 applied on the ceramic green sheets 17 and 19 are notched 17
It is formed so as to reach the edges 17b, 17b on the side opposite to the edges on which a, 19a are formed.

Electrode pastes 38 to 40 are printed on the ceramic green sheets 21 to 23 in order to form the third multilayer capacitor. The electrode pastes 38 and 40 are formed so as to reach the edges 21b and 23b on the opposite side of the edges where the cutouts 21a and 23a of the ceramic green sheets 21 and 23 are formed, respectively. The electrode paste 39 is drawn out to one end edge portion 22b of the ceramic green sheet 22 which sandwiches the notch 22a.

The ceramic green sheets 11 to 24 shown in FIG. 1 are laminated in the illustrated state to obtain a laminate, which is pressure-bonded in the thickness direction and then integrally fired to obtain a sintered body 50 shown in FIG. can get.

This sintered body 50 includes ceramic green sheets 11 to 24.
A recess 51 is formed on the side surface of each of the cutouts 11a to 24a. The above-mentioned internal electrodes are drawn out to a pair of outer side surface portions sandwiching the recess 51 and a side surface opposite to the side where the recess 51 is formed, and the first to third external electrodes 52 are provided.
By providing ~ 54 as shown, a multilayer capacitor block is obtained.

The internal electrodes in FIG. 5 are given the same reference numbers as the electrode pastes in order to facilitate correspondence with the electrode pastes in FIG.

As is clear from the comparison between FIG. 1 and FIG. 5, the first multilayer capacitor is formed in the portion of the internal electrode group consisting of the internal electrodes 31 to 33. The connected internal electrodes 31, 33 are electrically connected to the first external electrode 52, and the internal electrode 32 connected to the other potential is connected to the second external electrode 53.

Further, in the internal electrode group forming the second multilayer capacitor, the internal electrodes 34 and 36 are connected to the first external electrode 52, and the internal electrodes 35 and 37 are connected to the third external electrode 54.

Similarly, in the third internal electrode group forming the third multilayer capacitor, the internal electrodes 38 and 40 are electrically connected to the third external electrode 54, and the internal electrode 39 is electrically connected to the second external electrode 53. There is.

Therefore, it is understood that the multilayer capacitor block of the equivalent circuit shown in FIG. 3 is constructed by this embodiment.

The number of internal electrodes forming each laminated capacitor, that is, the number of laminated ceramic green sheets coated with the electrode paste shown in FIG. 1 is not limited to that shown in the figure. That is, in each of the first to third multilayer capacitors, the ceramic green sheets coated with the electrode paste may be further stacked to achieve higher capacity.

However, preferably, the electrode paste shown in FIG. 1 is used.
33 and the electrode paste 34 or the electrode paste 37 and the electrode paste 38, by equalizing the pattern of the adjacent electrode paste between adjacent multilayer capacitors,
It is possible to more effectively prevent interference between the multilayer capacitors. Therefore, even when the number of layers is increased,
Adjacent electrode paste patterns between adjacent multilayer capacitors are preferably equal as shown.

In addition, in the above-described embodiment, the notches 11a to 24a are formed in each of the ceramic green sheets 11 to 24 so that the recess 51 is formed on the side surface of the sintered body 50. However, this recess 51
Are merely provided for facilitating the provision of the first and second external electrodes 52, 53. Therefore, when it is easy to form the plurality of external electrodes in a non-conductive state, it is not always necessary to form the recess 51.

For example, even if the first and second external electrodes are provided on different side surfaces of the sintered body 50 and the internal electrodes are drawn out so as to be electrically connected to the dispersed first and second external electrodes. Good.

Further, also in the step of forming the recess 51, the recess 51 may be formed by stacking the ceramic green sheets and punching the stacked body after stacking.

〔The invention's effect〕

As described above, according to the present invention, the three capacitors used in the delta connection circuit are provided in the form of an integrated multilayer capacitor block. Therefore, in constructing the delta connection circuit, the mounting space can be reduced, and the mounting efficiency can be effectively increased, and the cost of the device using the delta connection circuit can be effectively reduced. . Not only that, each capacitor is made up of multilayer capacitors,
It is easy to obtain a large capacitance that could not be obtained with a single plate type capacitor. Further, among the first to third internal electrode groups, since the adjacent internal electrodes of one internal electrode group and the other internal electrode group adjacent in the thickness direction are connected to the same potential, the adjacent internal electrode groups It is possible to effectively reduce the crosstalk between the capacitors configured by. Further, since the internal electrodes connected to the same potential are separated by the sintered body layer, the dielectric strength is also increased.
Therefore, it is possible to realize a delta connection circuit having excellent characteristics, even though the multilayer capacitor block is configured by integrating the three capacitors as described above.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a ceramic green sheet and an electrode paste used to form an embodiment of the present invention, FIG. 2 is a circuit diagram showing a power supply circuit, and FIG. 3 is an embodiment of the present invention. 4 is a perspective view of an embodiment of the present invention, and FIG. 5 is a sectional view taken along the line VV of FIG. In the figure, 31 to 33 are internal electrodes (electrode paste) of the first multilayer capacitor, 34 to 37 are internal electrodes of the second multilayer capacitor (electrode paste), 38 to 40 are internal electrodes of the third multilayer capacitor ( Electrode paste), 50 is a sintered body, 52 is the first
External electrode, 53 is a second external electrode, and 54 is a third external electrode.

Claims (1)

(57) [Claims] 1. A multilayer capacitor block in which three capacitors used in a delta connection circuit are built in a state of being connected according to the delta connection circuit, and a sintered body made of dielectric ceramics, A plurality of internal electrodes arranged so as to overlap each other in the thickness direction with a dielectric ceramic layer in the sintered body, wherein the plurality of internal electrodes form first to third multilayer capacitors in the thickness direction. In order to do so, the first to third internal electrode groups arranged in the thickness direction are configured, and the internal electrode connected to one potential of the first and second internal electrode groups is a side surface of the sintered body. An inner electrode connected to the other potential of the first inner electrode group,
The internal electrode connected to one potential of the third internal electrode group and the internal electrode connected to the other potential of the second and third internal electrode groups are connected to the second lead portion of the side surface of the sintered body. One of the first to third internal electrode groups is adjacent to each other in the thickness direction and is adjacent to the other internal electrode group, which are respectively drawn out to the third extended portion on the side surface of the sintered body. The internal electrodes are connected to the same potential, and the internal electrodes connected to the same potential are separated by a sintered body layer. A multilayer capacitor block provided with a third external electrode.