GB580675A - Improvements in and relating to windings for electric apparatus and method of making same - Google Patents

Abstract

580,675. Winding coils. BRITISH THOMSONHOUSTON CO., Ltd. Oct. 23, 1944, No. 20499. Convention date, Oct. 23, 1943. [Class 120 (ii)] [Also in Group XXXV] In a pot-type current transformer, an insulating tubular wall 12 which is integral with the porcelain pot casing 10, is loosely surrounded by a metal spool 30 on which is the high voltage winding. To wind the high voltage conductor on, the spool 30 which.is in two halves is placed together round the tubular wall 12 with an insulating strip separating the halves to prevent the spool acting as a short-circuited turn, and driving chains 46 are placed on the spool in engagement with teeth 40 round each edge. The spool is driven from a wheel 65 thereby winding on insulating material 44 and a thin, wide copper strip 41, which forms the high voltage winding and has its end brazed to the spool, while the friction which might damage the porcelain surface is reduced by a spring-urged thrust member 50 carrying two wheels 51, 52 bearing against the spool. Terminals 25, 26 are connected respectively by leads 56, 56<1> to the outer end of the winding and to a bridge member screwed to the spool. An iron core 16, 17 passes through the tubular member 15 where it is surround by the low voltage winding 28. To locate the spool and winding, the pot cavity 11 may be filled with a suitable compound to level 62.