Abstract: A copy machine having a high accuracy sheet registration system for precise placement of images on each copy sheet. The copy machine includes sensors with charge coupled devices (CCDs) that detect the sheet positions in two dimensions within the machine, and detect sheet arrival times at various positions with the machine. Using this detected information, the copy machine employs a multi-stage process to bring the sheet into contact with a color image moving on a photoreceptor belt, in synchronism with the position and speed of the image on the belt. The copy machine also monitors its own condition and makes predictions about needed preventive maintenance, to instruct personnel to service the machine before the machine fails.

Abstract: An electrostatographic reproduction machine includes a stalling preventing copy sheet placement assembly for effectively placing copy sheets of varying sheet stiffness at its image transfer station. The stalling preventing copy sheet placement assembly includes a first baffle and a second baffle defining a pre-transfer sheet path for guiding a copy sheet towards placement against the photoreceptor at the transfer station, and a rotatable, low drag sheet placement roller located at an exit end of the pre-transfer sheet path, and electrically biased, for controlling and driving the copy sheet out of the pre-transfer sheet path into placement against the photoreceptor, thereby reducing drag on the copy sheet and preventing sheet stalling of even relatively high stiffness copy sheets at the transfer station.

Abstract: A sheet handling system for correcting the skew and/or transverse position of sequential sheets, especially those moving in a process direction in a sheet transport path of a reproduction apparatus to be registered for image printing, of the type in which the deskewing and/or side registration is accomplished by partially rotating the sheet with a transversely spaced pair of differentially driven sheet steering nips. The effective range of sheet size capabilities of such systems may be increased without steering nip slippage or other problems by applying a control signal proportional to the width of the sheet to a system for automatically increasing or decreasing the transverse spacing between the pair of sheet steering nips, so as to provide a much wider spacing for larger sheets yet still be able to handle small sheets.

Abstract: A sheet handling system for a sheet transport path of a reproduction apparatus having a sheet skew correction system being fed image substrate sheets in the process direction by a sheet transport system, wherein it is desired to positively feed and yet effectively deskew a wide range of different lengths of sheets in the process direction. A plurality of identical but independent sheet transport units may be provided spaced along the sheet transport path in the process direction engageable with a sheet being fed through sheet transport path for positively feeding even very short sheets from one sheet transport unit to another and to the skew correction system. Yet these sheet transport units provide independently automatically disengageable nips for automatically releasing even a very long sheet from any unit when that long sheet is in the skew correction system. A different selected number of the sheet transport units are disengaged in response to a different sheet length control signal.

Abstract: An apparatus for advancing a sheet. The apparatus includes a transport which has the sheet releasably secured thereto in one mode of operation, and, in another mode of operation reduces the frictional force between the sheet and the transport to facilitate relative movement therebetween. A controller, in communication with the transport, selects the mode of operation of the transport.

Abstract: An apparatus for registering a sheet with a developed image on a moving surface. The apparatus includes a transfer station, detector, memory, and a registration transport. The detector is located at the transfer station and generates a registration signal in response to a sheet edge and a registration portion of the developed image. The memory stores sheet position factors and responds to the detector to update the factors. The registration transport communicates with the detector and the memory to move the sheet to the transfer station in registration with the developed image.

Abstract: In a duplex printing integrity system for insuring that correctly matching pages are being printed by a duplex printer on the opposing first and second sides of the sheets, the duplex printer having a duplex loop path circulating sheets printed on one side back to be printed on their opposite side and an output path for feeding out the duplex sheets after they have been printed on both sides; the printer is operable to selectively print a few small, simple solid marks spaced along the sheets, specifically printing a sequence of sheets with correspondingly spaced and parallel print marks, with different spacings of the marks on the sheets for different sheets in the duplex loop.

Abstract: An apparatus for detecting the level of material in a container. The apparatus comprises a power source and a first electrode, positioned adjacent the container, electrically connected to the power source. The apparatus further comprises a second electrode. The second electrode is spaced from the first electrode and positioned adjacent the container. The apparatus further comprises an electrical amplifier which is electrically connected to the second electrode. The amplifier amplifies a current induced in the second electrode and generates a voltage signal. The amplifier is adapted to maintain the second electrode at a virtual ground to minimize environmental impedance effects. The apparatus further comprises a rectifier, electrically connected to the amplifier, for rectifying the voltage signal and a comparator, electrically connected to the rectifier, for comparing the voltage signal to a predetermined voltage signal corresponding to the container being full with material.

Abstract: An apparatus for removing magnetic granules from a moving imaging surface in a region between a developer station and a transfer station is provided. The apparatus includes a member, interposed between the developer station and the transfer station. The member has a plurality of grooves in the exterior surface thereof. Each of the grooves have a width greater than each portion of the member between adjacent grooves. The apparatus also has a magnetic member operatively associated with the member. The magnetic member generates a magnetic field to attract the magnetic granules from the imaging surface to the member. The member and the magnetic member are adapted to move relatively to one another. The member is eccentrically mounted in a housing so that two air passageways of different dimensions are formed between the member and the housing so that the air flow in the respective air passageways are different from each other.

Abstract: A sealed system for collecting and removing waste imaging material from a reproduction apparatus in a waste collection container removably insertable into the reproduction apparatus so that the inlet opening of the container is positioned at discharge outlet of a pneumatic cleaning system, especially, the outlet of a cyclone air/toner separator. The container has a dual mode resilient pneumatic seal surrounding its inlet, and an integral insertion guide member. The cleaning system discharge outlet includes a spring loaded sled member and a flexible pneumatic seal connecting between the sled member and the discharge outlet to allow limited movement of the sled member. The insertion guide member of the container slides on an entrance guide path into compressed superposed engagement with the sled member to form a pneumaticaly-sealed waste material path between the discharge outlet of the reproduction apparatus cleaning system and the interior of the waste container when so inserted.

Abstract: An electrophotographic printing machine in which an electrostatic latent image is recorded on a moving photoconductive surface by charging the appropriate areas of the surface to predetermined polarities. The latent image is a developed in a development zone with toners of a preselected color and predetermined polarity which are delivered by magnetic bead carriers. A bead removal device is provided adjacent the surface and downstream from the development zone relative to the movement of the surface. The bead removal device magnetically attracts carrier beads off the photoconductive surface. The beads are then deposited in a sump. A vacuum source is also provided for urging beads into the sump from the surface. The bead removal device comprising a sleeve mounted for rotation in a housing, adjacent the surface. The sleeve has a fixed magnet disposed proximate the surface therein and a shunt disposed generally opposite the magnet to define an attraction zone and a release zone.

Abstract: An improved system for exchanging a developer unit of a copying or printing machine by moving the developer unit between a portable developer unit transporter cart or the like and the development station of the machine while the cart is docked in alignment therewith, the cart has a liftable development unit holder and a simple but effective foot pedal operated lifting system for automatically lifting it up to the same level as the development station in said machine, so that developer unit rails thereon are in accurate alignment with rails in the development station for easily moving a developer unit therebetween, irrespective of variations in the level of the cart and the machine due to floor or machine alignment differences. Also disclosed is a system of assisting the lateral alignment of the cart with the machine for docking, and safety interlock systems.

Abstract: An apparatus in which copy sheets are sorted into sets of copy sheets and positioned at a discharge region by trays mounted slidably on a frame in the finishing station of an electophotographic printing machine. Each tray has an entrance region and an exit region Copy sheets are received at the entrance region of the trays. Successive trays are moved to the set discharge region where completed sets of copy sheets are removed from the exit regions thereof.