Abstract: A charging apparatus that prevents fogging due to light generated by a corona source. The charging apparatus includes two offset reference electrodes lying in separate horizontal planes or a light eclipsing element positioned between a corona source and an electrode member.

Abstract: An ionographic printer bar directs a stream of ions from an integral ion source having a planar surface for emitting ions to a charge receptor to create an electrostatic latent image thereon. The ion stream passes through an aperture having associated therewith a focusing pinch electrode for narrowing the ion stream to a preselected width, displacing electrodes for positioning the narrowed ion stream within the aperture, and focus electrodes. The integral ion source is placed in propinquity in relation to the ionographic printer bar. The planar design of ion source allows reduce size of the ionographic printer bar because no support frame is needed and allow increase robustness of the ionographic printer bar which makes it easy to install in a machine and easy to clean.

Abstract: An ionographic printer directs a stream of ions from a source to a charge receptor to create an electrostatic latent image thereon. The ion stream passes through a relatively large aperture having associated therewith a focusing pinch electrode for narrowing the ion stream to a preselected width, displacing electrodes for positioning the narrowed ion stream within the aperture, and focus electrodes. Varying the biases of the displacing electrodes causes the ion stream to scan across the aperture to deposit multiple spots of charged areas at desired locations on the receptor. Varying the biases of the focus electrodes cures positional and ion-stream cross-section anomalies.

Abstract: A scorotron charging unit for charging Verde film residing on the inner surface of an imagesetter drum has a charging region that encompasses a 270.degree. sector of the drum. The scorotron is fashioned by attaching a metallic strip coronode having a sawtooth edge around a section of pipe. Each tooth of the sawtooth strip is bent to an angle of about 90.degree. with respect to the surface of the pipe. This pipe is slipped inside another pipe that includes a slit for the passage of ions in the direction of the Verde film, thus forming a scorotron. The scorotron while sliding through the drum holding this film, charges the film to sensitize it for imaging.

Abstract: A multi-color printer using a stretch toner release development system to provide either partial or full color copies with minimal degradation of developed toner patterns by subsequent over-development with additional colors and minimal back contamination of developer materials. Multiple scanning beams, each modulated in accordance with distinct color image signals, are scanned across the printer's photoreceptor at relatively widely separated points, there being a buffer provided to control timing of the different color image signals to assure registration of the color images with one another. Each color image is developed prior to scanning of the photoreceptor by the next succeeding beam. After developing of the last color image, the composite color image is transferred to a copy sheet. Development is accomplished by stretching the surface of a toner carrying member and thereby reducing the net force of adhesion of toner to the surface of the toner carrying member.

Abstract: A printing machine adapted to print an image on a plurality of different predefined sized sheets, including an imaging member adapted to receive the image on a plurality of predefined image areas on the surface of the imaging member. A selector is provided for selecting one of the plurality of different predefined sized sheets to be printed on. And, a corona generating device is provided for charging only one of the plurality of different predefined image areas associated with the one of the plurality of different predefined sized sheets selected.

Abstract: An ionographic printer directs a stream of ions from a source to a charge receptor to create an electrostatic latent image thereon. The ion stream passes through a relatively large aperture having associated therewith a pinch electrode for narrowing the ion stream to a preselected width, and displacing electrodes for positioning the narrowed ion stream within the aperture. Varying the biases of the displacing electrodes causes the ion stream to scan across the aperture to deposit multiple spots of charged areas at desired locations on the receptor. The electrodes can be designed to compensate for spot placement skew and anomalies in the cross-sectional shape of the displaced ion stream.

Abstract: An ionographic printer directs a stream of ions from a source to a charge receptor to create an electrostatic latent image thereon. The ion stream passes through a relatively large aperture having associated therewith a focusing pinch electrode for narrowing the ion stream to a preselected width, and displacing electrodes for positioning the narrowed ion stream within the aperture. Varying the biases of the displacing electrodes causes the ion stream to scan across the aperture to deposit multiple spots of charged areas at desired locations on the receptor.

Abstract: A scorotron charging device for charging the surface of a receptor includes a ribbon coronode with a curvilinear field modifying screen surrounding a major portion of the ribbon to level the charge and decrease the possibility of arcing.

Abstract: A printing apparatus includes a charging device for charging the surface of a receptor with the charging device including a ribbon coronode with field modifying electrodes parallel to the ribbon that decrease the possibility of arcing.

Abstract: A charging device includes a thin (1 mil) conductive strip edge-on used as a coronode.

Abstract: A scorotron like charging device includes an ion generator from which ion flow is controlled by fringe fields developed along an edge of an electrode sandwich located near the ion source.

Abstract: A miniature coronode charging device comprising a plurality of coronode wires that are slanted with respect to the direction of travel of a charge receptor in order to reduce the effective distance between "hot spots" in the wires and thereby insure uniform charging of the receptor. The length of coronode wires between support points and their conducting contacts is very small, thereby eliminating sagging, singing, tensioning and capacitance problems when providing a corotron charging device of unlimited length. Individual high impedance to the plurality of coronode wires is provided in order to limit the amount of current passing to each of the wires from a high voltage source and thereby reduce the possibility of arcing and damages to the charge receptor. Spacing between coronoa wires and the charge receiving surface is small to provide low corona threshold and self-limiting charging.

Abstract: A charging device having a coronode that includes a comb-like ruthenium glass electrode silk screened onto a supporting dielectric substrate. The teeth of the comb-like electrode extend to an edge of the dielectric substrate and positionable relative to a screen or slit in several ways in order to form scorotron type devices.

Abstract: A self cleaning charging unit includes an insulating housing and a current limited, low capacitance corona wire positioned within the housing and located 0.5-6 mm away from biased conductive plates which form a slit through the bottom of the housing that allows ions to pass therethrough onto a receptor surface. The conductive plates are used to control the flow of ions through the slit and opposing insulating wedges are positioned above and incontacting relationship with each conductive plate in order to focus additional ions to the center of the slit. At inside edges of the slit there are additional fringe fields that aid in pumping ions out of the slit. Charging a receiver in corotron or scorotron fashion is possible with this charging unit.

Abstract: A touchdown development system includes a donor roll positioned closely adjacent a photosensitive member in order to develop an image on the surface of the photosensitive member. A reverse mounted doctor blade is employed in the system along with a toner pump in order to apply a smooth and uniform layer of toner onto the surface of the donor roll.

Abstract: A fluid jet assisted method for charging a receptor surface to a predetermined voltage includes the steps of generating ions in a chamber, entraining the ions in a rapidly moving fluid stream passing into, through and out of the chamber, depositing the ions on a charge receptor and biasing the back of the charge receptor with a bias equal to and of opposite potential of said predetermined voltage desired on the receptor surface. Both the ion generator and the receptor can be stationary for charging receptor plates or the like, or the receptor could be a moving belt or the like.

Abstract: A printing unit includes a current limited, low capacitance corona wire located 1-5 mm away from biased conductive plates which form a slit that allows ions to pass therethrough onto a receptor surface. The conductive plates are used to control the flow of ions through the slit and opposing wedges are positioned on each conductive plate in order to focus additional ions to the center of the slit. At inside edges of the slit there are additional fringe fields that aid in pumping ions out of the slit.

Abstract: A charging unit that is adaptable for use over indeterminate lengths without singing and sagging of corona wire(s) includes stringing the wire around pins positioned in the base of the charging unit in zig-zag fashion in order to provide overlap of charging from multiple segments of the wire. Alternatively, the wire(s) could be supported by a series of monofilaments positioned orthogonal to the direction of the wire(s) at periodic intervals. These charging units may be employed in either a corotron or scorotron configuration.

Abstract: A miniaturized scorotron corona generator for charging a thin wire or a receiver surface includes a sawtooth coronode partially surrounded by a conductive shield with a control screen attached to the shield. The control screen is closely spaced to the receiver surface such that fringing fields between the screen and receiver surface contribute significantly both to efficient ion pumping and to potential leveling.