TONER FIXING DEVICES FOR ELECTROPHOTOGRAPHIC COPYING APPARATUS

The fixing arrangement comprises a heated aluminum plate heating the lower face of a tone-image-bearing copy paper. The heated plate comprises two transverse ribs extending transverse to the copy-paper transport direction and, intermediate them, a sequence of transversely spaced longitudinal ribs, the transverse and longitudinal ribs intersecting to form individual recessed rectangular fields, each of which, when closed off from above by the copy paper, confines air heated by the heating plate to form a transversely extending zone of hot-air air cushions heating the lower face of the paper. Transversely extending suction channels located upstream and downstream of the hot-air air-cushion zone contain transversely extending rows of suction apertures, for holding the sheet down against the ribs and closing off the individual hot-air air cushions. At any given instant, the area of the sheet in direct physical contact with the heating plate is minimal, because the crests of the ribs are rounded off to establish virtually zero or line contact with the paper. The longitudinal ribs can be inclined relative to the transport direction, to prevent perceivable streaks in the final fused image.