DE2256268A1 - FRONT CONTACT ELECTRIC CAPACITOR - Google Patents

Description

Front-contact electrical capacitor.

The invention relates to an end-contact electrical capacitor with plastic films as dielectrics and on these applied, in particular regenerable thin metal coverings, in which an internal series connection 'Is produced by covering surfaces in that a first plastic film is wider than a second and "on both sides protrudes over the second plastic film and with at least zw ^ 'i isolated from each other, to the opposite Foil edges reaching covering surfaces is coated, while a second, narrower plastic film with at least a covering surface is coated, which leaves free edge zones free on both film edges and two on the first plastic film located covering areas overlaps, in which the edge areas of the covering areas on both sides of the wider plastic film are each contacted by a Schoopschicht.

Such a capacitor is from the German Offenlegungsschrift ' 1,764,680 known. If such a capacitor is to be properly contacted, it must the dielectric covered by the Schoop layers consist of a material that can be easily contacted, d. H. the slide is allowed to move not warped so much or even melted during the procurement process

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zen that short circuits or bad contacts to the Schoopschicnt occur. Therefore, relatively temperature-stable materials are used in such capacitors according to the prior art.

The object of the present invention is to improve the electrical properties of such a capacitor to enhance.

This object is achieved in a capacitor of the type described above in that the first, wider Plastic film made of a material that can be easily contacted and the second made of a less easily contactable material with particularly advantageous electrical properties consists.

The structure according to the invention has the advantage that, on the one hand, it enables good contacting of the capacitor and on the other hand the less advantageous electrical properties of the easily contactable materials the use of particularly advantageous dielectrics for the second dielectric sheet can be improved.

A particularly favorable combination of foils is obtained when the first, wider plastic foil is made of polycarbonate and the second plastic film consists of one of the substances polyethylene, polypropylene or polystyrene. Here has the use of polyethylene and polypropylene has the advantage that it also promotes regeneration, while polystyrene has a particularly low loss factor

1
having.

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Another improvement in dielectric properties is achieved in that at least between the wider plastic film and the "adjacent, to their non-metallized surface, adjoining covering surface a non-metallized plastic film with advantageous electrical properties is arranged.

By a corresponding number of consecutive Covering areas and the appropriate thickness of the foils used, the capacitor can achieve the required Tensions are adjusted.

In the following the invention is explained in more detail with reference to a figure; it is not related to that shown in the figure Embodiment limited.

On a poorly contactable film, for. B. polypropylene, existing dielectric layer 1 is a Covering area 2 arranged, which serves as a dummy covering. Above

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this is a likewise poorly contactable film 3, which is not vaporized. Above this is a wider one Well contactable film 4, preferably made of polycarbonate, arranged, applied to the two covering surfaces 5 and 6 which extend to the edge of the film and are isolated from one another by a film-free strip 7. Y / ird a Such a structure Beschoopt, only the contactable film 4 is covered by the contact layers; so it arises a stable contact. The poorly contactable foils and 3, on the other hand, ensure good electrical properties of the capacitor.

3 claims - 4 -

1 figure

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Claims (3)

P a t e η t α η s ρ r ü c h e .) Stimicontacted electrical capacitor with plastic foils as dielectrics and applied to these, in particular thin metal coatings that can be regenerated an inner series connection of pavement surfaces is produced in that a harvested plastic film is wider protruding as a second and on both sides over the second plastic film and with at least two of each other isolated 3 layers reaching to the opposite edge of the film is coated, while a second, narrower plastic film is coated with at least one covering surface, the free edge zones on both film edges is left free and overlaps two overlays located on the first plastic film, in which the edge areas the covering surfaces on both sides of the wider plastic film are contacted by a Schoop layer each are, characterized in that the first, wider plastic film made of a material that can be easily contacted and the second made of a less easily contactable material with particularly advantageous electrical properties consists. 2.) Capacitor according to claim 1, characterized in that the first, wider plastic film made of polycarbonate and the second plastic film made of one of the substances polyethylene, polypropylene or polystyrene. 3.) capacitor according to claim 1 or 2, characterized in that at least between the wider plastic film and the neighboring, non-metallized surface 409824/0399 VPA 9 / HO / 2041 adjoining covering surface a non-metallized plastic film with advantageous electrical properties is arranged. VPA 9/140/2041 409824/0399 Blank page