JPS6044819B2 - film capacitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a film capacitor comprising alternating double-sided metallized films and dielectric layers.

In conventional film capacitors, the width of the laminated film wound together with the double-sided metallized film is narrowed, and end electrodes are formed on metal thin film layers at both ends of the double-sided metalized film by metal spraying or the like. Similarly, in a film capacitor formed by winding or laminating a film-like material on which a dielectric layer 2 is provided on the surface of a double-sided metallized film 1 by a coating method or the like, the dielectric layer 2 is The width was narrower than the width of the double-sided metallized film 1, forming a so-called coating merge part 3. (For example, Jikko 42-2
However, when the thickness of the dielectric layer 2 and the thickness of the double-sided metallized film 1 are thin, the adjacent double-sided metalized film 1 may adhere due to warping of the double-sided metalized film 1, and the end electrodes may be damaged. There was a drawback that the metal layer and the end electrode were not sufficiently bonded because the sprayed metal to be formed was allowed to flow in. This also resulted in an increase in tatδ, resulting in a disadvantage that the performance as a capacitor deteriorated.
Further, as another conventional technique, there is a structure in which the edge of the film (insulating paper) is made wavy or uneven.

(For example, Japanese Utility Model Publication No. 1123/1983) However, in this conventional structure, a single double-sided metallized film is cut into a wave shape and then rolled up, so that the end face on which the end face electrode is provided becomes uneven. It is technically difficult to cut a multi-layered metallized film into a wavy shape at once by cutting the metallized film, and the end surface does not become uneven in an effective sense. In other words, at the wavy edge, good contact is expected when the overlapping layers have different shapes, but this is because the same shapes may overlap, and if half of the layers appear as effective deposition surfaces, then good contact is expected. However, the other half has the problem that an ineffective non-deposited surface appears. This overlapping method is probabilistic, and the probability that a vapor deposition surface that is effective for contact with the end electrode will appear does not exceed 112 at maximum.
The present invention aims to eliminate the drawbacks of the conventional film capacitors and provide a film capacitor that has good electrical and mechanical contact between the metal thin film layer and the end face electrode, and also has a configuration suitable for mass production. That is, the present invention aims to provide a film capacitor that is highly effective when a manufacturing method for mass production is used.An embodiment of the present invention will be described below with reference to FIGS. 2 to 4.

FIG. 2 shows a film capacitor according to an embodiment of the present invention.

In FIG. 2, reference numeral 6 denotes a double-sided metallized film in which metal thin film layers 8 are formed on both sides of a film 7. 9 is a dielectric layer having a width narrower than the width of the double-sided metallized film.

The double-sided metallized film 6 and the dielectric layer 9 are alternately laminated, and coating margins are formed outside both ends of the dielectric layer 9. Reference numeral 10 denotes a bar-shaped dielectric layer formed in a bar shape in a part of the coating merge portion.

As is clear from the above structure, a gap exists without being blocked at least in the vicinity of the bar-shaped dielectric layer 10, and the sprayed metal forming the end electrode can easily flow. You can enter.

Note that the same effect can be obtained by replacing the bar-shaped dielectric layer 10 in the above embodiment with a spotted dielectric layer 11 as shown in FIG.

In addition, in the two embodiments described above, the coating merge portions were provided at both ends of the dielectric layer 9, but as shown in FIG. It is also possible to have a structure in which a dielectric layer is provided in a pattern or a pattern. As described above, according to the present invention, it is possible to obtain good contact between the metal thin film layer and the end electrode without directly adhering to each other due to warping, etc., and the end of the metallized film is straight, and the dielectric layer Since the chisel is tooth-shaped and does not punch out or scrape the metallized film, the material of the metallized film is not wasted, and there is no need to dispose of the material. It is a straight line, allowing for smaller material dimensions and providing a smaller capacitor.

[Brief explanation of drawings]

Figure 1A is a horizontal sectional view of a conventional film capacitor, Figure 1A is a vertical sectional view of the same, Figure 2A is a horizontal sectional view of a film capacitor showing an embodiment of the present invention, and Figure 2A is a horizontal sectional view of a conventional film capacitor. 3 is a horizontal sectional view of a film capacitor showing another embodiment of the present invention; FIG. 4A is a horizontal sectional view of a film capacitor showing still another embodiment of the present invention;
The opening in Figure 4 is a vertical sectional view of the same. 6... Double-sided metalized film, 7... ◆ Film, 8... Metal thin film layer, 9... Dielectric layer, 10... Crosspiece shaped dielectric layer, 11...
- Spotted dielectric layer.

Claims (1)

[Scope of Claims] 1. A dielectric film with a constant width formed by alternately laminating a plurality of double-sided metallized films with metal thin film layers formed on both sides of the film and a plurality of dielectric layers, and having a constant width formed at the end portions. A film capacitor characterized in that the dielectric layer is partially provided in the body layer margin portion from at least a part of the edge of the double-sided metallized film toward the inside. 2. Claim 1, characterized in that a dielectric layer is provided in a cross-shaped or spot-like manner in a part of the margin part.
Film capacitors as described in section.