US Patent 7059100 Induction sealing device for heat sealing packaging material

There is described an induction sealing device for heat sealing packaging material for producing sealed packages of pourable food product and fed in a first direction. The sealing device has induction means interacting with the packaging material by means of a pair of first active surfaces and a pair of second active surfaces interposed between the first active surfaces in the first direction; and the second active surfaces have, in the first direction, a width greater than the width of the first active surfaces at least along most of the length of the first and second active surfaces in a second direction perpendicular to the first direction.