Patent ID: 7675009

Claim:
An induction device ( 1 ) of a machine for electromagnetic induction welding of the layers of a multi-layer printed circuit, the induction device ( 1 ) comprising: a magnetic circuit ( 2 ) fitted with a field winding provided with an upper induction electrode ( 5 s ) and a lower induction electrode ( 5 i ) magnetically connected to corresponding arms of the magnetic circuit ( 2 ) and arranged coaxially to each other, the upper induction electrode ( 5 s ) and the lower one ( 5 i ) being capable of moving vertically in both directions, wherein the end of each induction electrode ( 5 s , 5 i ) destined to come into contact with the multi-layer printed circuit is provided with a thermal barrier, made up of a heating element comprising an electrical heating circuit ( 8 s - 8 i , 9 s - 9 i , 10 s - 10 i ) which heats the electrodes in order to prevent, during the welding, heat transmission by thermal conductivity from the welding zone to the electrode, and wherein the electrical heating circuit is distinct from the magnetic circuit and the field winding, and wherein the electrical heating circuit directly heats the electrodes.