JPH021363B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a metallized film capacitor in which a safety function is provided to the capacitor element itself.

In recent years, there has been a strong demand for safety measures for capacitors, and various measures have been taken regarding safety functions, and the ones that are generally put into practical use utilize the deformation of the case caused by the pressure at the time of destruction. It is designed to cut the lead wire. However, these structures have a problem of being complicated and expensive. Therefore, recently, as shown in FIG. 1, a margin part 1 is provided at the end in the width direction, and a plurality of margin parts 2 are provided intermittently in the length direction continuous with the margin part 1 to form a divided electrode 3. A capacitor element 5 is constructed by laminating and winding a pair of metallized films 4, and a large number of small-capacity capacitor elements are connected in parallel within the element 5. During use, a part of the divided electrode 3 may break due to some abnormality. Even if an explosion occurs, only the function of that part is lost and the effect on other capacitor elements is eliminated, thereby preventing an explosion from occurring, which is attracting attention. However, as a conventional means for forming a plurality of margin parts intermittently in the length direction, there is a method disclosed in, for example, Japanese Patent Laid-Open No. 118623/1983. As shown in FIG. 2, what is disclosed in this publication is a metallized film 8 in which a vapor deposited electrode 7 is provided on the entire surface of the metallized film 8, leaving a margin 6 at one end in the width direction. The first electrode roller 9, which is conductive, and the second electrode roller 11, which has a plurality of conductive parts 10 on the insulating outer peripheral surface, are brought into contact with each other at a constant interval, and the first electrode roller 9 and the second electrode roller 9 are brought into contact with each other at a constant interval. 11, a voltage is applied by the power supply 12 to feed the metallized film 8 in the direction of the arrow, and the vapor deposition electrode 10 in the portion in contact with the linear conductive portion 10 is scattered by sparks, thereby causing an intermittent flow in the length direction. A plurality of margin portions 13 are formed. However, with this method, the scattered vapor-deposited electrode powder adheres to the conductive part 10, so not only is the scattering insufficient, but also the film is damaged by the vapor-deposited electrode powder, resulting in poor insulation resistance and breakdown voltage resistance. It had the disadvantage of decreasing.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a method for manufacturing a metallized film capacitor in which a margin portion is provided by non-contact discharge to provide a safety function to the capacitor element itself.

The contents of the present invention will be explained below with reference to the drawings. That is, as shown in FIG. 3, a semi-cylindrical insulator 22 with a linear electrode 21 disposed inside is fixed, and an insulating support roller 13 in the shape of a hexagonal column, for example, is placed inside the semi-cylindrical insulator 22 to support the linear electrode 21. It is constructed in such a way that it can rotate without contacting it. Next, between the insulating support roller 23 and the linear electrode 21 disposed on the semi-cylindrical insulator 22, a metallized film 26 with a vapor-deposited electrode 25 formed on the entire surface, leaving a margin 24 at one end in the width direction, is placed. A conductive roller electrode 27 is brought into contact with the evaporation electrode 25 and is moved in the direction of the arrow, and a high voltage is applied by a power source 29 between the linear electrode 21 and the conductive roller electrode 27 via a current limiting resistor 28. Apply. However, metallized film 2
6, the hexagonal column-shaped insulating support roller 23
rotates, causing a non-contact discharge in a portion of the vapor deposition electrode 25 located at the corner 30 of the linear electrode 21 and the insulated support roller 23, scattering the vapor deposition electrode 25 in that portion, and continuously feeding the metallized film 26. As a result, a plurality of margin portions 31 are formed intermittently in the length direction and then wound using a winder (not shown) to obtain a metallized film capacitor in which a safety function is provided to the capacitor element itself. . FIG. 4 is a bottom view showing the semi-cylindrical insulator 22 on which the linear electrode 21 is arranged.

According to the above method, since the vapor-deposited electrode is scattered in a non-contact manner, there is no mechanical stress applied to the metallized film, that is, damage to the metalized film due to vapor-deposited electrode powder, unlike in the case of scattering using the conventional contact method. It has the advantage of stable insulation resistance and breakdown voltage characteristics.

Next, the effects of the present invention will be described with reference to Examples.
That is, metals with a rating of 200 V ₃ AC - 4 μF according to the present invention in which a plurality of margin parts are formed by the non-contact method shown in FIG. 3 and the conventional example in which a plurality of margin parts are formed by the contact method shown in FIG. The insulation resistance and breakdown voltage resistance of a polyethylene terephthalate film capacitor are shown in FIGS. 5 and 6. In addition, the diameter of the linear electrode in the present invention is
Using a 0.3mm tungsten wire, the applied voltage is
AC3000V, metallized film feeding speed is 50
mm/sec to 100 mm/sec, and the distance between the helical electrode and the corner of the hexagonal columnar insulated support roller was set to 0.5 mm. Furthermore, in the conventional example, the first electrode roller has the entire circumferential surface metalized, and the second electrode roller has a tungsten wire provided as a conductive part on the outer circumferential surface of an insulating material, and the applied voltage is DC70V. . Note that the spacing between the margin parts is the same as in the conventional example of the present invention.
The diameter was 10 mm, and the number of samples was 20 each. As is clear from FIGS. 5 and 6, the device according to the present invention exhibited stable characteristics compared to the conventional example.
In the above description, the insulating support roller 32 is exemplified as a hexagonal columnar roller, but as shown in FIGS. It can also be applied to 33 is a corner. In addition, the 10th linear electrode provided inside the semi-cylindrical insulator
If the linear electrode 34 is made up of a plurality of divided pieces as shown in the drawings and FIG. 11, it is more effective in improving the feeding speed. 35 indicates a semi-cylindrical insulator.

As described above, according to the present invention, which scatters the deposited electrode by non-contact discharge and forms a plurality of margin parts intermittently in the length direction of the metallized film, the capacitor element itself has stable insulation resistance and breakdown voltage characteristics. A method for manufacturing a metallized film capacitor provided with a safety function can be obtained.

[Brief explanation of drawings]

Fig. 1 is an exploded perspective view of a general capacitor element with a safety function during winding, Fig. 2 is a schematic diagram showing the main steps of the conventional example, and Fig. 3 is the main steps of the present invention. 4 is a bottom view showing the semi-cylindrical insulator with the linear electrodes shown in FIG. 3, FIG. 5 is an insulation resistance characteristic diagram, FIG. 6 is a breakdown voltage characteristic diagram, and FIG. 9 are perspective views showing insulated support rollers according to other embodiments of the present invention,
FIGS. 10 and 11 are bottom views showing semi-cylindrical insulators according to other embodiments of the present invention in which the arrangement of linear electrodes is changed. 21, 34... Linear electrode, 22, 35... Semi-cylindrical insulator, 23, 32... Insulated support roller, 25
...Vapour-deposited electrode, 26...Metalized film, 27...
...Roller electrode, 28...Current limiting resistor, 29...
Power supply, 30, 33... corner, 31... margin section.

Claims (1)

[Claims] 1. A conductive roller electrode is brought into contact in advance between a linear electrode provided inside a semi-cylindrical insulator and a polygonal columnar insulated support roller configured to be rotatable without contacting the linear electrode. At the same time, a high voltage is applied between the linear electrode and the roller electrode via a current limiting resistor, and the metallized film is placed between the corner of the linear electrode and the insulated support roller. The metallized film capacitor is characterized in that a plurality of margin portions are intermittently formed in the length direction of the metallized film by scattering the vapor-deposited electrode by non-contact discharge, and then a wound capacitor element is formed. Production method.