EP 0165435 B1 19871125 - METHOD FOR MANUFACTURING A LOW TENSION COIL FOR TRANSFORMERS
Title (en)
METHOD FOR MANUFACTURING A LOW TENSION COIL FOR TRANSFORMERS
Publication
Application
Priority
DE 3418823 A 19840521
Abstract (en)
[origin: EP0165435A1] 1. A method of manufacturing low-voltage coils (5) for transformers made of strip material (15) rolled up in a spiral with insulating interlayers (16) ant with a casting (17) made of casting resin on each of the two annular end faces, characterized in that a solvent-free mixture of polyepoxy and polyisocyanate resin, known per se, serves as the casting resin ; that this mixture is hardened within a few minutes of being poured onto each end face by the addition of a reaction accelerator at room temperature, to a self-supporting annular casting (17) which can already be mechanically loaded at room temperature ; that the hardened castings (17) of the same coil (5) are both further hardened simultaneously at 1008C to 1408C, so that they can also by mechanically loaded at elevated temperature ; and that the further hardened castings (17) on the hardening temperature being exceeded in the course of operation by raising of the glass transition temperature (glass transformation temperature), harden further without softening.
IPC 1-7
IPC 8 full level
H01F 41/12 (2006.01)
CPC (source: EP)
H01F 41/127 (2013.01)
Designated contracting state (EPC)
AT BE CH DE FR GB IT LI NL SE
DOCDB simple family (publication)
EP 0165435 A1 19851227; EP 0165435 B1 19871125; AT E31126 T1 19871215; BR 8502366 A 19860121; DE 3561089 D1 19880107
DOCDB simple family (application)
EP 85105657 A 19850508; AT 85105657 T 19850508; BR 8502366 A 19850520; DE 3561089 T 19850508