Multiple-blade pickoff for electrophotographic copier

Abstract

Apparatus for separating a copy sheet from a photoconductive imaging surface in an electrophotographic copier following image transfer in which a plurality of guides are stationarily disposed at transversely spaced locations across the imaging surface at sufficiently small spacings therefrom to intercept the leading edge of a copy sheet moving past the guides and separate the sheet edge from the surface. The guides are disposed at progressively retarded positions relative to the movement of the imaging surface to effect laterally progressive peeling of the leading edge of the copy sheet from one lateral edge to the other and have such progressively decreasing lengths along arcuate guide paths as to compensate for their progressively retarded positions and direct the sheet onto an exit path with a leading edge orientation corresponding to its original orientation in the transfer station. To achieve initial separation, the first guide is disposed at a spacing from the imaging surface less than the thickness of a copy sheet and is assisted by a pulsed air jet against the adjacent leading sheet edge portion. A pressure roller in the transfer station clamps the sheet portion behind the sheet edge intercepting the air jet to prevent air from flowing through the region between the sheet and the imaging surface and undesirably reducing the pressure in that region.