JPH10149939A - Layered metallized film capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the entire capacitor smoking, burning, and breaking even when a cut surface of a layered metallized film is not insulated well or abnormal voltage is applied. SOLUTION: A layered metallized film capacitor is constituted in such a way that a metallized film 1 is piled on another metallized film or a non- metallized film and they are cut. At least one metal vapor-deposited electrode 2 out of facing two metal vapor-deposited electrodes 2 and 2a is provided with a net pattern electrode, which bridges polarized and vapor-deposited electrodes fractionized into a plurality of pieces and is connected with a fuse part 4 crossing a margin part 3 in between.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated metallized film capacitor mainly used for electric equipment, which is advantageous for energy saving, miniaturization of equipment and high efficiency.

[0002]

2. Description of the Related Art In recent years, high-density packaging has been promoted in electrical equipment as well as efficiency and size and weight have been reduced, and there has been an increasing demand for smaller and lower-priced capacitors to be used. I have. Also, the importance of the safety of capacitors has been emphasized, and the demand for safety devices such as a protection device against insulation breakdown and a safety device such as a thermal fuse has also been increased.

In the prior art, a multilayer capacitor capable of efficiently producing a capacitor element shape from a wound type and an end-faced oval type has been reduced in size and price, and a safety device,
We have provided highly safe metallized film capacitors by providing thermal fuses and the like. The laminated metallized film capacitor is composed of a metallized film 20 and a non-metallized film 2.
1 or a metallized film 20 is superimposed and wound and laminated on a metal bobbin, metal spraying is performed on both end surfaces of the film to form a metallikon 24, and further heat aging to remove a metal bobbin (not shown). To form a large capacitor, which is cut into a predetermined size with a cutting blade to form a single capacitor. Further, the security mechanism is disclosed in JP-A-61-2313,
As disclosed in JP-A-280410 and JP-A-6-310368, a fuse portion is formed on the metal-deposited electrode 12, or the metal-deposited electrode 22 is divided into a plurality of pieces to make the entire capacitor a collection of minute capacitors. Even if dielectric breakdown occurs in one part of the entire capacitor that functions as a dielectric, the metal deposition electrode of the part involved in the dielectric breakdown part is electrically disconnected from the entire capacitor and released. However, it is possible to prevent dielectric breakdown of other minute capacitor portions. However, the metallized film using the finely divided metal deposition electrodes 22a and 22b as a security mechanism as shown in FIG. 3 and FIG. 4 is not used for a laminated metallized film capacitor, and is not used for a wound type capacitor or an end face oval. Used only for type capacitors. this is,
Since the area of the metal deposition electrode in one layer of the laminated metallized film capacitor is small, FIGS.
This is because it is not necessary to divide the metal deposition electrode into a plurality of pieces as in the above. In addition, a safety device and a safety device are provided with a mechanical weak point in a conductive portion inside the outer container in advance, and the mechanical weak point is separated by an increase in the internal pressure of the outer container, and the electric power to the multilayer capacitor is cut off. This shuts off the supply of energy. In the conventional example shown in FIG. 5, a fuse portion 23 is formed on at least one of the two metal-deposited electrodes 22 facing each other, and a double-sided metallized film 20 serving as a security mechanism is provided. Chemical film 2
1 and rolled and laminated on a metal bobbin, zinc metal spraying is applied to both ends of the film to form metallikon 24, and further heat aging, and the metal bobbin (not shown) is removed to form a large ring. A capacitor base was cut with a cutting blade to obtain a laminated metallized film capacitor. With this laminated metallized film capacitor, miniaturization and cost reduction can be achieved.
Even if a dielectric breakdown occurs in a part of the dielectric film in one place of the entire capacitor, the metal deposition electrode of the part involved in the dielectric breakdown is electrically isolated from the entire capacitor. To prevent the other capacitor parts from dielectric breakdown.

[0004]

In order to obtain a laminated metallized film capacitor, the wound and laminated large ring capacitor matrix is cut into a single capacitor with a cutting blade. Instead, the cut surface is insulated by melting the film end surface of the element cut surface with the resistance heat of the cutting blade. However, in the conventional example (FIG. 5),
When insulation of the cut surface is not properly obtained or an abnormal voltage is applied in actual use, dielectric breakdown easily occurs at the cut surface, and the dielectric breakdown portion becomes the cut surface. The security mechanism provided with the fuse portion 23 that passes through the electrode margin portion 25 as in the conventional example is difficult to operate, and finally has a problem that the entire capacitor is destroyed with smoke or ignition. Further, since the cut surface of the element is insulated by melting the end face of the film by the cutting blade, the cutting withstand voltage level is very low, and only a capacitor having a low rated voltage can be designed. For this reason, a capacitor having a high rated voltage has a problem that an efficient production method cannot be obtained unlike a wound type, and it is difficult to reduce the size and the price.

The present invention solves the above-mentioned conventional problems. Even if insulation of a cut surface of a multilayer capacitor is not properly obtained or an abnormal voltage is applied in actual use, the capacitor can be used. It is an object of the present invention to provide a laminated metallized film capacitor having high safety and high voltage design that does not break down due to smoking or ignition.

[0006]

In order to achieve the above object, a laminated metallized capacitor according to the present invention comprises a laminated metallized film obtained by laminating a metallized film with another metallized film or a non-metallized film. Film capacitor, wherein at least one of the opposed two metal-deposited electrodes is
The metallized film has a mesh-like pattern electrode connected to each other through a fuse portion crossing a margin portion by bridging a plurality of micro-deposition electrodes subdivided into a plurality of pole metal deposition electrodes.

[0007]

As described above, the laminated metallized film capacitor of the present invention has a structure in which at least one of the opposed two metal-deposited electrodes is divided into a plurality of finely divided metal-deposited electrodes. Are partially bridged with each other and have a mesh pattern electrode connected via a fuse section that crosses the margin section.The insulation of the cut surface due to the cutting process is not good, or abnormal voltage in actual use However, even if dielectric breakdown occurs in one part of the element cut surface that functions as a dielectric, the micro-deposited electrode of the part involved in the dielectric breakdown part is electrically isolated from the entire capacitor and released, and the other Since the dielectric breakdown of the minute capacitor portion can be prevented, the capacitor does not break down due to smoke or ignition. In addition, even if a capacitor is used at a high voltage, since a metallized film having a security mechanism using a mesh-shaped pattern electrode as described above is used, even if a dielectric breakdown occurs at a voltage weak point portion of an element cut surface, The micro-deposited electrode of the part involved in the dielectric breakdown part is electrically cut off from the entire capacitor and separated, preventing the other micro-capacitor part from being broken down. Since it is electrically disconnected from the entire capacitor and separated, the insulation distance between the cut surface of the element and other minute capacitor portions can be obtained.
Therefore, it is possible to maintain the insulation of the element cut surface enough to withstand the high voltage design.

Hereinafter, the present embodiment will be described with reference to FIGS. 1 and 2. Reference numeral 1 denotes a double-sided metallized film in which a metal containing zinc as a main component is vapor-deposited on both surfaces of a polypropylene film which is a dielectric film. like,
There is a mesh pattern electrode connected between a plurality of subdivided micro-deposited metals via a fuse portion 4 crossing the margin portion 3. Reference numeral 5 denotes a non-metallized film as a dielectric film, and 6 denotes a metallikon in which a double-sided metallized film 1 and a non-metallized film 5 are overlapped and wound and laminated on a metal bobbin, and both ends of the film are sprayed with zinc metal. is there. Further, heat aging was performed, and a metal bobbin (not shown) was removed to obtain a large annular capacitor base.

Further, the capacitor body of the large ring was cut with a cutting blade to obtain a capacitor of the present embodiment.

The above-mentioned laminated metallized film capacitor was subjected to a dielectric breakdown test in an atmosphere at room temperature of 24 ° C. and 70 ° C., and the results are shown in Table 1.

[0011]

[Table 1]

From Table 1, it can be seen that all of the conventional laminated metallized film capacitors broke down with smoke due to dielectric breakdown at the cut surface of the element, whereas all of the capacitors of the present embodiment were secured. The mechanism operated and did not lead to destruction with smoke or ignition. In this embodiment, at least one of the two metal-deposited electrodes 2 and 2a opposed to each other has a plurality of finely-divided finely-deposited electrodes, and the fuse portion partially crosses the margin portion 3 with each other. Since the security mechanism uses the mesh pattern electrodes connected in step 4, even if a dielectric breakdown occurs at a portion of the multilayer capacitor element cut surface that functions as a dielectric, a portion involved in the dielectric breakdown portion This is because the electrode was electrically disconnected from the entire capacitor and separated, thereby preventing the other minute capacitor portions from dielectric breakdown. Next, a voltage of AC 400 V was applied to the capacitor of the present example in an atmosphere of 70 ° C. to conduct an energization test. As a result, the capacity reduction rate (%) is shown in FIG. From FIG. 2, the capacitor of the conventional example has a large capacity reduction rate (%) of -13.0 (%) after 1000 hours (H) from the start of the test, whereas the capacitor of the present embodiment has a capacity of -3. 0 (%) and excellent life characteristics were obtained. This is because, in the present embodiment, the fuse portion 4 crosses the margin portion 3 between the minute vapor deposition electrodes subdivided into a plurality of at least one of the two opposite metal vapor deposition electrodes 2 and 2a. Since a metallized film is used as a security mechanism using connected mesh-shaped pattern electrodes, even if a dielectric breakdown occurs at the voltage weak point on the cut surface of the element, the micro-deposited electrode involved in the dielectric breakdown part is not affected. Electrically cut off from the whole capacitor and released, preventing other small capacitor parts from dielectric breakdown, and the micro-deposited electrode on the cut surface of the element is electrically cut off from the entire capacitor and released Therefore, it is possible to obtain an insulation distance between the element cut surface and another minute capacitor portion.

[0013]

As described above, according to the present invention, at least one of the two opposite metal-deposited electrodes is provided with a margin between the finely-divided minute-deposited electrodes. A metallized film that has a mesh pattern electrode connected by a traversing fuse section.Even if the insulation of the element cut surface of the multilayer capacitor is not properly removed, or if an abnormal voltage is applied in actual use,
Fuse that crosses the margin part operates reliably, the entire capacitor does not break down with smoke or fire, it has high safety, and has the effect of realizing a laminated metal film capacitor capable of high voltage design. It is.

[Brief description of the drawings]

FIG. 1 is a perspective sectional view schematically showing a laminated metallized film capacitor according to an embodiment of the present invention.

FIG. 2 is a diagram showing a capacity reduction rate characteristic comparing an embodiment of the present invention with a conventional example.

FIG. 3 is a partial plan view showing a mesh pattern electrode;

FIG. 4 is a partial plan view showing another mesh pattern electrode.

FIG. 5 is a perspective sectional view schematically showing a conventional laminated metallized film capacitor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Double-sided metallized film 2, 2a Metal deposition electrode 3 Margin part 4 Fuse part 5 Non-metallized film

Claims (3)

[Claims] 1. A laminated metallized film capacitor obtained by laminating a metallized film with another metallized film or a non-metallized film and cutting it to a predetermined size, wherein at least one of two opposed metal-deposited electrodes. Multi-layered metallized film capacitor that has a mesh pattern electrode connected to the metallized film by bridging the micro-deposited electrodes subdivided into a plurality of metallized electrodes, and connecting the fuses across the margin. . 2. The laminated metallized film according to claim 1, wherein the metallized film is formed by depositing a metal-deposited electrode containing zinc as a main component on both sides of the dielectric film with a thicker electrode lead-out side and a thinner insulating end side. Metallized film capacitors. 3. The laminated metal according to claim 1, wherein the metallized film is formed by depositing a metal-deposited electrode containing zinc as a main component on the dielectric lead film thicker on the electrode lead-out side and thinner on the other insulating end side. Chemical film capacitor.