GB958447A - Production of wound-type electrical capacitors - Google Patents

Abstract

958,447. Capacitors. GENERAL ELECTRIC CO. Oct. 4, 1962 [Oct. 4, 1961], No. 37621/62. Heading H1M. A capacitor comprises a dielectric layer having two electrode foils adhesively secured to opposite surfaces, with two aligned oppositely projecting elongated conductors secured and electrically connected to the respective foils; the foil and dielectric assembly being rolled about the conductors. In Fig. 1, an adhesively coated strip 1 of polyethylene terephthalate, P.T.F.E., vinyl, polyester, polyamide, cellulose, or kraft paper carries foils 2, 3 of e.g. aluminium on opposite faces; foil 3 overlapping foil 2 with an insulating margin on all sides. Conductors 4, 5 of e.g. copper are welded, soldered, or secured by conducting adhesive to the respective foils and project laterally on opposite sides with the foil connecting ends stepped (Fig. 2a) so as to overlap to form a circular core (Fig. 2). The assembly is folded along the axis of the conductors and then rolled about such axis (Fig. 4) or twisted about the axis (Fig. 4a) constituting a roll capacitor with conductors protruding from the ends (Fig. 5). Alternatively, the conductors may be located at one end of the assembly and an additional dielectric strip may adhesively overly one of the foil electrodes; the assembly being rolled about the conductors as before (Figs. 6, 7, not shown). The additional dielectric may be continuous with that separating the electrodes and folded back over conductors (Fig. 8, not shown). The conductors may be of copper clad-steel and the roll may be inserted in a glass ceramic, metal or plastic shell encapsulated with plastic or wrapped with plastic tape. The foils may be laterally offset or the roll compressed into an oval or flattened shape.