JPH10116751A - Capacitor unit - Google Patents

Abstract

(57) [Summary] (with correction) [PROBLEMS] To provide a capacitor unit which can be used with necessary and sufficient capacitance and which can obtain a high allowable ripple current. SOLUTION: A pair of conductors 3, 4 are formed symmetrically with respect to a certain center on a main surface of a unit substrate 1, and a pair of capacitors 6, 6 are mounted symmetrically on both sides of the center of the unit substrate 1. At the same time, the terminal electrodes of these capacitors 6, 6 are connected in parallel to the pair of conductors 3, 4. Such a plurality of unit boards 1 are connected to each other at the central portion, and external terminals connected to one conductor 3 and the other conductor 4 of each unit board 1 are provided at the connection points.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a capacitor unit having a plurality of capacitors connected in parallel, and more particularly to a capacitor unit having a large capacitance and a high allowable ripple current.

[Prior art]

Conventionally, an aluminum electrolytic capacitor has been used as a capacitor used in a circuit in which a high ripple current flows at a high frequency, such as an inverter control circuit and a switching power supply. If the capacitance of the aluminum electrolytic capacitor is small, the allowable ripple current is low. Therefore, a capacitor having an extremely large capacitance has been used for the purpose of lowering the impedance of the circuit. This is because increasing the capacitance of the capacitor of the circuit increases the electrode area of the capacitor, and as a result, the resistance value of the capacitor decreases, and a high allowable ripple current can be obtained. On the other hand, other capacitors, for example, a multilayer ceramic capacitor, have an allowable ripple current of about 1 when compared with an aluminum electrolytic capacitor having the same capacitance value.
It is about 0 times.

[0003]

The aluminum electrolytic capacitor used as described above has an unnecessarily large capacity as a circuit, and its shape becomes extremely large. On the other hand, multilayer ceramic capacitors are
The absolute value of the capacitance is insufficient for use as the inverter circuit or the switching power supply as described above. For this reason, it is not possible to cope with a ripple current as high as several tens of Arms by itself.

The present invention has been made in view of the problem of the conventional capacitor which requires such a high allowable ripple current, and can be used with a necessary and sufficient capacitance, and a high allowable ripple current can be obtained. It is an object to provide a capacitor unit that can be used.

[0005]

According to the present invention, in order to achieve the above object, a plurality of capacitors 6, 6,... Are connected in parallel to obtain a high capacitance, and all the capacitors 6, 6,. The current flows evenly so that a higher allowable ripple current, which is a multiple of the allowable ripple current per capacitor 6, equal to the number of capacitors used is obtained. As means therefor, a pair of conductors 3 and 4 formed on the unit substrate 1 are attached to the unit substrate 1
A pair of capacitors 6 so as to be symmetric with respect to the center of
6 are mounted, and the conductors 3 and 4 are connected to the external electrodes 7 and 8 at the center of the plurality of unit substrates 1.

That is, in the capacitor unit according to the present invention, a pair of conductors 3 and 4 are formed on the main surface of the unit substrate 1 symmetrically with respect to a certain center thereof, and
Are mounted symmetrically on both sides of the center of the unit substrate 1, and the terminal electrodes of these capacitors 6, 6 are connected in parallel to the pair of conductors 3, 4, so that the plurality of unit substrates 1 are connected to each other at the center. It is characterized in that external terminals 7 connected to one conductor 3 and the other conductor 4 of each unit substrate 1 are provided at the connection points.

For example, the conductors 3 and 4 of the unit substrate 1
The capacitors 6 and 6 are mounted on both ends of the unit substrate 1, and the terminal electrodes at both ends of the capacitors 6 and 6 are connected to the conductors 3 and 4, respectively. Each is connected. Capacitor 6,
6 is easy to mount on the unit substrate 1 having a small chip capacitor. Especially small and relatively high capacitance,
It is preferable to use a multilayer ceramic capacitor having a high allowable ripple current.

In such a capacitor unit, since a plurality of capacitors 6, 6,... Are connected in parallel, a large capacitance can be obtained. Moreover, since the capacitors 6, 6,... Of each unit board 1 are connected symmetrically with respect to the center of the unit board 1, all the capacitors 6, 6,.
Are connected symmetrically to the external terminals 7 connected to the conductors 3 and 4 at the center of the unit substrate 1, respectively. Therefore, if the plurality of capacitors 6, 6,... Have the same characteristics such as capacitance and impedance, the current flowing through the external terminals 7, 8 is equally distributed to each of the capacitors 6, 6,. Exactly equal currents flow. That is, assuming that the number of capacitors 6, 6,... Is n, a ripple current of 1 / n of the total ripple current can be equally divided and flow through each capacitor 6, 6,. As a result, a capacitor unit having a high capacitance value as a whole and a high allowable ripple current can be obtained.

For example, the unit boards 1 are connected so that their centers cross each other. As a result, both sides on which the capacitors 6 and 6 of each unit board 1 are mounted are arranged radially from the joint. More specifically, the plurality of unit substrates 1 have slits 5 along the center line thereof, and the slits 5 are alternately inserted up and down so as to form a radial wing around the connection point by the insertion of the slit 5. Be linked. Furthermore, the connecting portion of the unit substrate 1 is fixed by a fixing member. At this time, by using a conductor as the fixing member, the fixing member can also serve as the external terminal 7 for connecting the capacitor unit to a circuit. In such a capacitor unit, a plurality of unit substrates 1 are coupled in a wing shape of a water wheel, and a portion corresponding to the axis of the water wheel serves as an external terminal 7. Is easy.

Each of the pair of capacitors 6 mounted on both sides of the unit substrate 1 may be mounted on the same main surface of the unit substrate 1. In order to prevent the capacitors 6 and 6 mounted on the adjacent unit substrates 1 from interfering with each other when they are connected to each other, the pair of capacitors 6 and 6 may be mounted on different main surfaces. Further, a pair of capacitors 6 are provided on both sides of both main surfaces of the unit substrate 1, respectively.
When 6 are mounted, the same number of capacitors 6 and 6 can be connected in parallel with a smaller number of unit substrates 1.

[0011]

Embodiments of the present invention will now be described specifically and in detail with reference to the drawings.
FIG. 1 shows one unit substrate 1 on which two capacitors 6 and 6 are mounted. The unit substrate 1 has conductors of the same material, thickness and width, for example, aluminum, on one of its main surfaces along one of the opposed long sides of the substrate 2.
A pair of conductors 3 and 4 made of a metal such as silver, copper, and nickel are formed in parallel.

The unit substrate 1 is coated with an insulating material in the longitudinal direction of the center of the substrate 1 made of a metal plate such as an aluminum plate, and the exposed aluminum surfaces on both sides thereof are plated with copper to be exposed from the insulating coating. Metal parts are conductors 3 and 4. Alternatively, a copper plate may be used as the substrate, and the copper portions exposed without plating on the surface may be used as the conductors 3 and 4. Further, a glass epoxy resin substrate or an alumina substrate having an insulating property may be used as the substrate 2, a conductor film may be provided on the main surface thereof, and the conductor film may be used as the conductors 3 and 4.

A slit 5 is cut in the center of the unit substrate 1 in the longitudinal direction so as to be orthogonal to the long side from the long side. If this slit 5 connects two unit substrates 1, for example, the slit 5 is cut only from one long side of the unit substrate 1,
The depth of the lit 5 is relative to the entire width of the unit substrate 1.
What is necessary is just to make the depth which subtracted the depth of the slit 5 of the unit board | substrate 1 of the other party to insert. Most generally, the unit substrate 1 may be provided at a depth from one long side of the unit substrate 1 to a width thereof, that is, approximately の of a dimension in a height direction in FIG.
The width is set slightly wider than the thickness of the unit substrate 1.

On the other hand, if three or more unit substrates 1 are to be connected, the intermediate unit substrate 1 excluding the first unit substrate 1 and the last unit substrate 1 to be inserted has slits 5 cut from the long sides on both sides thereof. , Those slits 5
Is a depth obtained by subtracting the depth of the slit 5 of the unit board 1 to be inserted from the entire width of the unit board 1.

Capacitors 6, 6 are mounted on both sides of the main surface of the unit substrate 1, and their terminal electrodes are connected to the conductors 3, 4,
Connected to each other. These capacitors 6, 6
It is preferable that the same electric characteristics such as capacitance and impedance are used, and that the form and structure are also the same. Each terminal electrode of the capacitors 6, 6 is connected to a slit 5
Are connected to the conductors 3 and 4 respectively at the same distance d from the center of the unit substrate 1 provided with. In other words, the capacitors 6 are mounted symmetrically with respect to the center of the unit substrate 1 in the longitudinal direction.
The capacitors 6, 6 are advantageous because they are easy to mount on the unit substrate 1 in the form of chips. In particular, multilayer ceramic capacitors have relatively high capacitance and high allowable ripple current among chip capacitors. So most preferred.

A plurality of such unit substrates 1 are prepared, and first, as shown in FIG.
The slits 5 and 5 are inserted together with the slits 5 and 5 intersecting at about 90 °. At this time, as described above, one long side of the unit substrates 1 and 1 has a width of 1
When the two unit substrates 1 and 1 having the slits 5 having a depth of / 2 are connected to each other, the slits 5 and 5 are connected to each other in the slits 5 and 5 at about 約 of the center of the opposing unit substrates 1 and 1.
Is inserted, with the two unit substrates 1 and 1 intersecting at 90 ° at the center in the longitudinal direction.

On the other hand, when connecting three or more unit substrates 1, first, as shown in FIG. 2, the first unit substrate 1 having a deep slit 5 is provided, and a shallow slit 5 and a deep slit 5 are provided. The second unit substrate 1 is
The shallow slit 5 of the second unit substrate 1 is inserted into the deep slit 5 of the first unit substrate 1 and connected. At this time, the depth of the shallow slit 5 and the depth of the deep slit 5 of the two unit substrates 1 to be connected are set to a value obtained by subtracting the depth of the slit 5 of the unit substrate 1 to be inserted into each other from the entire width of the unit substrate 1. Although not shown,
Further, when inserting the third unit substrate 1, the unit substrate 1 having the shallow slit 5 and the deep slit 5 is inserted.
And connect the third shallow slit 5 into the second deep slit. Also in this case, the shallow slit 5 and the deep slit 5 of the two unit substrates 1 to be connected are equal to the total width of the unit substrate 1 minus the depth of the slit 5 of the other unit substrate 1 to be inserted into each other. I do. Then, the slit 5 is inserted into the center of the already inserted two unit substrates 1 and 1 in a state in which each of the two unit substrates 1 and 1 intersects about 45 °, and the three substrates 3 are inserted. The eye unit board 1 is inserted. Hereinafter, the slits 5 of the fourth and subsequent unit substrates 1 are sequentially inserted while the shallow slits 5 and the deep slits 5 are alternately inserted while changing the intersecting angle of the unit substrates 1, and they are connected.

Thus, a desired number of unit substrates 1, 1,... Are inserted. Thereby, the unit substrates 1, 1
Are arranged in a radial plane with respect to the insertion portion, and a plurality of unit substrates 1, 1,. .. Can be connected in such a manner that the capacitors 6, 6 are connected to other adjacent unit substrates 1,
Are determined in a range where they do not come into contact with each other. Therefore, the number of unit boards 1, 1,.
The distance between the capacitors 6 and 6 from the center of the unit substrate 1 is determined by the thickness d of the unit substrate 1. If the distance d of the capacitors 6, 6 from the center of the unit substrate 1 is increased, the capacitor unit becomes large.
In order to reduce the size, it can be said that it is preferable to use capacitors 6 having a particularly low height.

3 and 4 show a state in which ten unit substrates 1, 1,... Are connected at their centers in this manner. With the unit boards 1, 1,... Connected in this manner, both sides of the connection intersection are fixed by metal shaft-shaped external terminals 7, 8, respectively. These external terminals 7 and 8
The conductor 4 divided by the slit 5 shown in FIGS.
Of the other conductor 3 and to the center of the other conductor 3. Thus, all the capacitors 6, 6,... Are connected in parallel to the external terminals 7, 8 via the conductors 3, 4. As a result, between the external terminals 7, 8, the number of capacitors 6, 6,..., For example, in the examples of FIGS.
Capacitances for 20 capacitors 6, 6,... Are obtained.
As described above, the external terminals 7 and 8 also have a function as a fixing member for fixing the plurality of unit substrates 1, 1,... At their connection portions and an electric terminal for connecting the capacitor unit to a circuit of the electronic device. .

Here, the widths and lengths of the conductors 3, 4 from the external terminals 7, 8 to the external terminals of the capacitors 6, 6,... Are the same. As described above, since the characteristics such as the capacitance and the impedance of all the capacitors 6, 6,... Are the same, when a current flows between the external terminals 7, 8, the current is changed to the respective capacitors 6, 6,. And they carry exactly the same current. That is, 1 / n of the current flowing through the external terminals 7 and 8 can be equally divided and passed through each of the 20 capacitors 6. Thus, a capacitor unit having an allowable ripple current that is a multiple of the number of capacitors 6, 6,...

However, in the example of FIGS. 3 and 4, FIG.
As is clear from the above, since the capacitors 6 and 6 mounted on both sides of the unit substrates 1 and 1 are both mounted on the same surface of the unit substrates 1 and 1, the capacitors 6 and 6 face each other at a certain place. And the interval between them becomes extremely narrow. Therefore, for example, as shown in FIG. 4, it is necessary to arrange a dummy substrate 2 'on which the capacitors 6, 6 are not mounted, or to connect the unit substrate 2 by skipping the unit substrate 2 by one angle pitch. It may be. Therefore, the number of capacitors 6, 6,... In this case is 18, and a capacitor unit having an allowable ripple current that is 18 times higher than the allowable ripple current of the capacitor 6 alone can be obtained.

On the other hand, the example shown in FIG.
1 are mounted on the opposite sides of the unit substrates 1, 1... By doing so, the capacitors 6, 6 as described above
Interference between them is avoided. Therefore, in the example of FIG.
The number of capacitors 6, 6,...
An allowable ripple current that is 20 times higher than that of a single unit is obtained.

Further, in the example shown in FIG. 6, capacitors 6, 6 mounted on both sides of the unit substrates 1, 1,... Are mounted on both side surfaces of the unit substrates 1, 1,. In this way, half of the unit substrates 1, 1
..., the same number of capacitors 6, 6,... As those in the example shown in FIG. That is, FIG.
Can connect 20 capacitors 6, 6,... With five unit substrates 1, 1,..., And obtain an allowable ripple current 20 times higher than the allowable ripple current of the capacitor 6 alone. .

For example, a substrate 1 made of an aluminum plate having a thickness of 0.8 mm is coated with insulation in the central longitudinal direction, and copper plating is applied to the exposed aluminum surfaces on both sides thereof.
The metal part exposed from this insulating coating is
4 and an outer diameter of 5.0 mm × 5.7 mm × 1.
Unit board 1, 1 on which a pair of capacitors 6 and 6 having 5 mm, capacitance of 5 μF and allowable ripple current of 1 Arms are mounted.
... were prepared. Then, these unit substrates 1
Were connected as shown in FIG. 5 to obtain a capacitor unit having a capacitance of 100 μF and an allowable ripple current of 20 Arms.

[0025]

As described above, according to the present invention, the allowable ripple current of each of the plurality of capacitors 6, 6,... Is a multiple of the number of capacitors 6, 6,. A capacitor unit is obtained. As a result, it is possible to obtain a capacitor unit that can be used with necessary and sufficient capacitance and that can obtain a high allowable ripple current.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one unit substrate used for an example of a capacitor unit according to the present invention.

FIG. 2 is a perspective view showing a process of connecting two unit substrates when assembling a capacitor unit using the unit substrate.

FIG. 3 is a perspective view showing an example of a completed capacitor unit according to the present invention.

FIG. 4 is a bottom view showing an example of the completed capacitor unit.

FIG. 5 is a bottom view showing another example of the completed capacitor unit according to the present invention.

FIG. 6 is a bottom view showing another example of the completed capacitor unit according to the present invention.

[Brief description of the drawings]

 DESCRIPTION OF SYMBOLS 1 Unit board 2 Board 3 Conductor 4 Conductor 5 Slit 6 Capacitor 7 External terminal 8 External terminal

Claims (9)

[Claims] In a capacitor unit comprising a plurality of capacitors connected in parallel, a pair of conductors (3) and (4) are symmetrically formed on a main surface of a unit substrate (1) with respect to a certain center thereof.
And a pair of capacitors (6) and (6) are mounted symmetrically on both sides of the center of the unit substrate (1), and terminal electrodes of the capacitors (6) and (6) are connected to the pair of conductors. (3) and (4) are connected in parallel, and the plurality of unit substrates (1) are connected to each other at the center,
An external terminal (7) connected to one conductor (3) and the other conductor (4) of each unit board (1) is provided at the connection point. 2. Unit boards (1) are connected so that their centers cross each other, and both sides of each unit board (1), on which the capacitors (6) and (6) are mounted, are radially arranged from the joint. The capacitor unit according to claim 1, wherein: 3. The unit substrate (1) has slits (5) along the center line thereof, and the slits (5) are alternately inserted vertically and connected. The capacitor unit according to the above. 4. The capacitor according to claim 1, wherein a pair of capacitors mounted on both sides of the unit substrate are mounted on different main surfaces. The described capacitor unit. 5. The unit according to claim 1, wherein a pair of capacitors is mounted on both sides of both main surfaces of the unit substrate. Capacitor unit. 6. The external terminal (7) is connected to a unit substrate (1).
The capacitor unit according to any one of claims 2 to 5, wherein the capacitor unit also serves as a fixing member for fixing the connecting portion of (1). 7. The conductor (3) of the unit board (1),
(4) A pair of strip-shaped conductors facing in parallel on the unit substrate (1).
The capacitor unit according to any one of the above. 8. The capacitors (6) and (6) are mounted on both ends of the unit board (1), and the terminal electrodes at both ends of the capacitors (6) and (6) are connected to the conductors (3) and (4).
The capacitor unit according to claim 7, wherein the capacitor unit is connected to each of the capacitors. 9. The capacitor according to claim 1, wherein the capacitors are multilayer ceramic capacitors.
The capacitor unit according to any one of the above.