Abstract: A method of intermingling images of different sizes on a photosensitive surface and yet avoid the seam of the photosensitive surface and synchronize the transfer of the images to intermingled copy sheets of various sizes by determining the size of each image before projecting the image onto the photo sensitive surface; predicting the relationship of the image to the seam of the photosensitive surface; deciding that a given image would overlay the seam of the photosensitive surface, applying a timing adjustment to project the given image onto the photosensitive surface in avoidance of the seam of the photosensitive surface, and transferring each of the images including said given image from the photosensitive surface to copy sheets whereby images of different sizes are intermingled along the photosensitive surface and copy sheets of different sizes are intermingled along the copy sheet path.

Abstract: An interlock system for a machine cover including an optical sensor providing a cover open signal, a housing secured to the cover and defining a hollow cavity communicating with the optical path with the cover closed, a reflector fixed to one end of the cavity to reflect light to the sensor with the cover closed, a wall forming part of the housing and disposed in an interference relationship with the optical path for blocking light with the cover open, the length of the optical path with the cover open being less than the length of the optical path with the cover closed, and circuitry to trigger the optical sensor to provide light pulses at a predetermined frequency.

Abstract: An apparatus for maintaining the outermost surface of a stack of sheets at a selected elevation of the type having a stacking tray for holding the stack, a drive system adapted to move the tray, a position sensor for detecting the position of the outermost sheet of the stack, and a drive controller for controlling the drive system in response to signals received from the position sensor. The drive controller utilizing signals generated by a travel limit sensor, whereby the sensor indicates, with an active signal, the presence of the stacking tray at either a first or a second travel limit position. The drive controller further utilizing signals generated by a motion sensor, whereby the sensor signal is indicative of displacement of the stacking tray. The apparatus further including a sensor actuating apparatus, operatively connected to the stacking tray, for actuating the travel limit and motion sensors.