Phase control of a seamed photoreceptor belt

Abstract

An apparatus and associated method for controlling the velocity of the photoreceptor within a reprographic machine having a seamed, web type photoreceptor, for producing a plurality of images thereon. The images being separated by unexposed interdocument regions on the photoreceptor. The reprographic machine further including a registration apparatus for registering copy substrates with developed latent images. The process of assuring that the seamed region of the photoreceptor lies within an interdocument region begins by first sensing an actual phase relationship between the photoreceptor seam and the activity of the registration apparatus and then calculating a phase error value by comparing the actual phase relationship to a desired phase relationship. Next, the system determines an adjustment photoreceptor velocity as a function of the phase error. Subsequently, the photoreceptor is moved at a fixed velocity during exposure of the images. Changing the calculated reference and hence photoreceptor velocity is restricted to the interdocument zone, so that there are no velocity changes except when the interdocument zone is passing through the imaging station. This ensures that the registration requirements and image quality specifications are simultaneously accomplished.