GB766946A - Improvements in or relating to high-voltage transformers - Google Patents

Abstract

766,946. Transformers. PHILIPS ELECTRICAL INDUSTRIES, Ltd. Dec. 9, 1954 [Dec. 12, 1953], No. 35677/54. Class 38 (2). A high-voltage transformer comprising at least one secondary winding-say 13-wound at constant pitch in an axial direction and a primary winding 17 concentrated adjacent one of the ends of the secondary winding is characterized in that internally of the secondary winding 13 is arranged a core member 5 made of a substantially non-conductive ferromagnetic ferrite material and which has an axial length approximately equal to the axial length of the secondary winding, each end of the core member 5 being in contact with a member of comparatively high electrical conductivity, as shown, 7 or 9. In the disclosed embodiment two secondary and two primary windings are used, one of each on each of two core members 3, 5, the ends of the secondary windings being connected to adjacent members 19, 21 which are in electrical connection with the conducting members 7, 9, the member 21 being earthed. In a further embodiment the secondary windings 11, 13 have differing numbers of turns, the upper ends of the two windings then being connected to the ends of the primary winding of a transformer 23 instead of to the member 19, this transformer having a centre tap of the primary winding connected to the member 9. The core members 3, 5 are preferably made of a nickel-zinc ferrite having a resistivity of 108 ohms per centimetre cube whilst the members 7, 9 are preferably made of a manganese-zinc ferrite having a resistivity of from 50 to 100 ohms per centimetre cube.