GB1263842A - Method of and apparatus for induction heating of flat bodies - Google Patents

Abstract

1,263,842. Induction heating coils. VSESOJUZNY NAUCHNO - ISSLEDOVATELSKY INSTITUT ELEKTROTERMICHESKOGO OBORUDOVANIA. 15 June, 1970, No. 28906/70. Heading H5H. Uniform heating of a flat rectangular body 2 is obtained using inductors 1, 3, generating orthogonal magnetic fields H 1 , H 2 , of controlled power at the same frequency and with means for periodically reversing the phase of one of the fields, the fields H 1 , H 2 acting in the plane of the flat body 2. The main inductor 1 is an elongate rectangular shape coil surrounding the body 2, preferably with its centre and end winding sections fed from separate sources of power supply. Two supplementary inductors 3, with magnetic yokes 4, are located mainly along the length of body 2, but in the direction of its width at the end sections, as shown. Thus the induced currents i 1 , i 2 oppose or reinforce one another at the end sections, to give greater or lesser heating of body 2 in these sections than in the central section, and thus the polarity of current flow in inductor 3 is periodically reversed to achieve a mean intensity of heating at the comers of body 2 equal to the intensity of heating in its central zone.