Patent ID: 6222167
Filing Date: 2001-04-24
Classification: C21D,C23C,Y02P

Abstract:
An induction heating type alloying system for a galvanized steel sheet, comprising:an induction heating coil;a power source;an impedance matching apparatus provided between said induction heating coil and said power source, said impedance matching apparatus including,a matching transformer having a plurality of pairs of intermediate contact points for arbitrarily selecting a turn ratio, wherein a first one of said contact points of each of said pairs is connected to a selective one of terminals of the secondary winding of said matching transformer,an integrated switching device for selecting one of the plurality of pairs of said intermediate contact points to select a desired turn ratio, such that a maximum power source output is obtained even when a load impedance of the steel sheet varies, said switching device being arranged to integrally accommodate the plurality of pairs of said intermediate contact points of said matching transformer,wherein said switching device consists of a plurality of integrated switches with each of said switches having a pair of fixed electrodes connected to a respective pair of said intermediate contacts points and a moving electrode, all pairs of said intermediate contact points being provided on a single base plate with the second one of said contact points of each of said pairs of contact points being connected to the induction heating coil so that each of said integrated switches corresponds to one of the pairs of said intermediate contact points, wherein one of the plurality of moving electrodes selectively moves to make contact with corresponding one of the plurality of pairs of said fixed electrodes such that said contact points of one of the plurality of pairs of said intermediate contact points are electrically connected to each other.