Pick-off device for electrostatic copier

摘要

An improved pick-off device for a copying machine of the type in which the developed image is transferred from the surface of a photoconductor to a sheet of copy paper in which a thin semi-rigid blade having a knife edge at a transversely tapered end thereof is releasably secured to a resiliently restrained element of a clutch assembly mounted at a position at which the knife edge of the blade is resiliently biased into engagement with the photoconductor at a location in the path of the leading edge of a sheet to which an image has been transferred to guide the sheet into a narrow space between the normally stationary clutch element and a continuously driven clutch element. In response to the entry of the sheet into the narrow space the two clutch elements are coupled to cause the restrained element to move with the continuously driven element against the action of the restraining means to carry the sheet away from the photoconductor surface. After a predetermined concomitant rotation of the clutch elements as the leading edge of the copy sheet enters the nip between an upper delivery roller and a lower delivery roller which moves with the continuously driven clutch element, the normally restrained clutch element is advanced relatively to the continuously driven clutch element to release the sheet and to restore the knife edge precisely to its initial position.