JPH0621228Y2 - Chip type composite capacitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a chip-type composite capacitor, and more particularly to a chip-type composite capacitor in which an electrolytic capacitor element and a ceramic capacitor element are stacked.

[Conventional technology]

Generally, an electrolytic capacitor has a larger capacitance than a ceramic capacitor, so the impedance characteristics in the low frequency region are good, but since the equivalent series resistance is large,
It has the drawback of high impedance in the high frequency range. Therefore, in order to obtain good impedance characteristics in a wide range from the low frequency region to the high frequency region, the two capacitors are arranged on the circuit board so as to be electrically parallel to each other. If you place the two capacitors separately,
There is a problem that not only the mounting cost is doubled but also the mounting density is lowered.

As a means for solving this problem, a composite capacitor in which an electrolytic capacitor and a capacitor having good impedance characteristics are connected in parallel can be considered.

As a conventional technique, for example, Japanese Patent Publication Sho 55 shown in FIG.
-Leads 9a and 9b of the electrolytic capacitor 3a and leads 8a and 8b of the impedance characteristic improving capacitor 8 are connected to the terminals 11a and 11b so that the two capacitors are parallel to each other, and then housed in the container 12 as in Japanese Patent Publication No. 47718. After that, there is a composite capacitor in which the sealing member 10 seals a part of the terminals 11a and 11b so as to be exposed to the outside.

However, this composite capacitor has a structure in which the lead wires of two capacitors each having a lead wire are connected in parallel and then sealed in the same container, so not only is the external dimension increased, However, since it cannot be made into a chip type, it has a drawback that high-density mounting cannot be performed.

Therefore, as shown in FIG. 6, the anode lead wire 4 led out from the electrolytic capacitor element 3 and the flat portion 1c of the anode terminal.
Is electrically connected to the anode element 3 having a. After that, the electrode portion 6 of the ceramic capacitor element 5
There is a chip-type composite capacitor in which the flat portion 1c of the anode terminal and the electrolytic capacitor element are superposed and connected by a conductive adhesive 7.

[Problems to be solved by the device]

In the conventional chip type composite capacitor described above, the anode terminal of the electrolytic capacitor is overlapped and connected with the electrode portion of the ceramic capacitor element as shown in FIG. 6, so that this chip type composite capacitor is mounted on the ceramic capacitor element side. And have to. Therefore, when attempting to automatically mount this chip-type composite capacitor, the electrolytic capacitor element surface must be attached by suction. However, since the electrolytic capacitor element has a smaller number of flat portions than the ceramic capacitor element, there is a problem that the electrolytic capacitor element cannot be adsorbed by the adsorption nozzle. For the same reason, the chip-type composite capacitor as shown in FIG. 5 is chip-type, but has a drawback that it is very difficult to perform automatic mounting.

An object of the present invention is to provide a chip-type composite capacitor which has good impedance characteristics in a wide range, can be miniaturized, can be surface-mounted, can be reduced in cost, and can be automatically mounted.

[Means for Solving the Problems]

In the chip-type composite capacitor of the present invention, the anode lead wire drawn from the electrolytic capacitor element is electrically connected to the central protruding portion of the anode terminal having the central protruding portion, the upper flat portion and the lower flat portion to form an electrode. The electrode part of the completed chip type ceramic capacitor element is superposed on the upper surface of the anode terminal and the upper surface of the electrolytic capacitor element and electrically connected in parallel.

〔Example〕

Next, the present invention will be described with reference to the drawings. FIG. 2 is a perspective view of an anode terminal of the chip type composite capacitor of the present invention. The upper portion of the anode terminal 1 having the lower plane portion 1b is bent to form the upper surface portion 1a, and a notch is made in a part of the upper surface portion 1a and then bent to form the central protruding portion 2a.

FIG. 1 is a sectional view of a chip type composite capacitor according to a first embodiment of the present invention. An anode lead wire 4 drawn from the electrolytic capacitor element 3 is connected to the central protruding portion 2 of the anode terminal 1 by electric welding. Then, the electrode portion 6 of the chip-type ceramic capacitor element 5 on which the electrode formation is completed is connected to the upper surface portion 3a of the electrolytic capacitor element and the anode terminal 1, respectively.
It is connected to the upper surface 1a of the above with a conductive adhesive 7.

FIG. 3 is a sectional view of the second embodiment of the present invention. The central projection 2 is formed by bending the anode terminal 1 in the direction opposite to the upper surface 1a formed by bending the upper portion. Then, similarly to the first embodiment, the electrolytic capacitor element 3 and the chip-type ceramic capacitor element 5 are superposed and connected. In this embodiment, the outer dimensions are larger than those in the first embodiment, but since the upper surface 1a of the anode terminal 1 is not provided on the upper portion of the central protruding portion 2, the anode protruding from the electrolytic capacitor element 3 is attached to the central protruding portion 2. There is an advantage in assembling work that the work of connecting the lead wire 4 by electric welding is easy.

FIG. 4 shows impedance frequency characteristics. Graph 1 in Fig. 4 shows the tantalum condenser (capacity:
6.8 μF) impedance frequency characteristics of a single unit, graph 2 shows impedance frequency characteristics of a ceramic capacitor (capacity: 0.1 μF) single unit, graph 3 shows tantalum capacitor element (capacity: 6.8 μF) and ceramic capacitor element (capacitance: : 0.1 μF), the frequency characteristics of impedance of the chip type composite capacitor of the present invention are shown.

[Effect of device]

As described above, according to the present invention, the anode lead of the electrolytic capacitor is connected to the central protruding portion of the anode terminal having the central protruding portion, the upper flat portion and the lower flat portion, and then the upper surface portion of the electrolytic capacitor element and the anode terminal are connected. As shown in FIG. 4, the electrode part of the chip-type ceramic capacitor element is superposed on the upper surface of and is adhered with a conductive adhesive, so that it has the characteristics of an electrolytic capacitor with a large capacitance in the low frequency region, In the region, E. S. R (equivalent series resistance)
Is smaller than the conventional composite capacitor because not only a capacitor having the characteristics of a small ceramic capacitor, that is, a composite capacitor having good impedance characteristics in a wide range can be obtained, but also a chip type composite capacitor can be obtained. At the same time, there is an effect that surface mounting becomes possible and the size and cost of the device using the composite capacitor can be reduced.

Further, in the capacitor of the present invention, the mounting surface can be automatically mounted on the electrolytic capacitor side because the adsorption surface can be the chip type ceramic capacitor element side having the flat portion on the element body, which facilitates automatic mounting. There is.

[Brief description of drawings]

FIG. 1 is a sectional view of a chip type composite capacitor of the first embodiment of the present invention, FIG. 2 is a perspective view of an anode terminal of the chip type composite capacitor of the first embodiment of the present invention, and FIG. Sectional view of a chip type composite capacitor of a second embodiment of the invention,
Figure is a graph showing the frequency characteristics of impedance of the electrolytic capacitor and ceramic capacitor respectively and the chip type composite capacitor of the present invention. Fig. 5 is a sectional view of the prior art composite capacitor. Fig. 6 is an electrolytic capacitor element. FIG. 3 is a cross-sectional view of a conventional chip-type composite capacitor in which a ceramic capacitor element and a ceramic capacitor element are combined. DESCRIPTION OF SYMBOLS 1 ... Anode terminal, 1a ... Top surface, 1b ... Lower plane part, 1c ... Anode terminal plane part, 2 ... Center protrusion part, 3
...... Electrolytic capacitor element, 3a ...... Electrolytic capacitor, 4
...... Anode lead wire, 5 ... Chip type ceramic capacitor element, 6 ... Electrode part, 7 ... Conductive adhesive, 8 ... Characteristic improving capacitor, 8a, 8b ... Characteristic improving capacitor lead, 9a , 9b ... lead, 10 ...
... sealing member, 11a, 11b ... terminal, 12 ... container.

Claims (1)

[Scope of utility model registration request] 1. A chip type in which an electrode lead-out wire drawn out from an electrolytic capacitor element is electrically connected to a central protruding portion of an anode terminal having a central protruding portion, an upper flat surface portion and a lower flat surface portion, and electrode formation is completed. 2. The chip-type composite capacitor, wherein the electrode portion of the ceramic capacitor element is superposed on the upper surface of the anode terminal and the upper surface of the electrolytic capacitor element and electrically connected in parallel.