ISOLERING Foer HOEG- MEDELSPAENNINGSLINDNINGAR OCH OCH FOERFARANDE Foer FRAMSTAELLNING AV ISOLERING

摘要

1. An insulator for high and medium voltage windings, particularly for electrical machines, comprising a tape based on mica or mica paper which is glued on a textile or felt support made of glass or synthetic fibers, by means of an adhesive comprising the condensation product of a polyamine having the general formula H2 N-(CH2 )n -[NH-(CH2 )p ]q -NH2 with an epoxide resin, wherein n and p are integers from 1 to 5 and q is an integer from 0 to 5, said tape being impregnated after being wound on a conductor by an impregnation resin comprising an epoxide resin which is mixed with an equivalent quantity of liquid acid anhydride, and the tape and the adhesive containing a hardening accelerator of the impregnation resin, characterized in that the epoxide resin which is to condense with the polyamine is a solid epoxide resin of bisphenol A having two terminal oxyrane groups and an epoxide equivalent included between 400 and 1500, or a novolak epoxide resin having an epoxide equivalent included between 150 and 300 or a mixture of these latter products, and that the respective quantities of polyamine and of epoxide resin for condensation are chosen in such a way that an excess of amine functions subsist in the condensation product.