device for detaching a copy sheet from the photoconductive drum of an electrophotographic copying machine , wherein the drum has a radial protuberance to which the leading edge of the copy sheet is held by electrostatic attraction and wherein a pick off finger is fixedly mounted adjacent the periphery of the drum at such a distance from the periphery to engage the drum , during its rotation , only in correspondence with the protuberance , so as to detach the copy sheet from the drum .