Abstract: In an electrostatographic imaging apparatus employing at least one charging device, scorotron which consists of one or more fine wires supported on insulated blocks spaced between the photoconductive surface and a conductive or insulative surface parallel to it. A screen or grid is interposed between the corona wires and the photoconductive surface and the grid is maintained at a potential roughly equal to the potential desired on the photoconductive surface. The scorotrons geometry, the individual wires are from 1/2 to 11/2 inches apart and are spaced from the grid by about 3/4 of an inch. Field enhancement electrode(s) are placed on the screen and are biased at the same potential as the screen. The field enhancement electrode(s) enhance electrical performance.

Abstract: An electrophotographic printing machine in which an electrostatic latent image recorded on an imaging surface is developed with toner particles to form a visible image thereof, including a hopper containing a supply of carrier material; a first developer unit for developing the electrostatic latent image with toner particles of a first color; a second developer unit for developing the electrostatic latent image with toner particles of a second color; conduit for connecting the first and second developer unit to the hopper so that carrier material flows to the first and second developer unit; a first feeding system, in communication with the conduit, for regulating the amount of carrier to the first developer unit; a second feeding system in communication with the conduit, for regulating the amount of carrier to the second developer unit, and a controller for controlling the regulation rate of the first and the second feeding system independently.

Abstract: An apparatus for developing in a development zone a latent image recorded on a surface, including; a housing defining a chamber storing at least a supply of toner therein. A donor roll disposed of at least partially in the chamber of said housing and spaced from the surface. The donor roll is adapted to rotate about a longitudinal axis to transport toner to the development zone in a region opposed from the surface. An elongated electrode member is mounted stationarily in the development zone and extending in a direction transverse to the longitudinal axis. The electrode member includes a flexible thin sheet having a plurality of elongated wires with adjacent wires which are spaced from and substantially parallel to one another. The electrode member is positioned in the development zone and spaced between the surface and said donor roll.

Abstract: An electrophotographic printing machine of the type in which an electrostatic latent image recorded on a charge retentive surface is developed with toner particles to form a visible image thereof. A Hybrid Scavengeless Development (HSD) developer housing designed to control toner emission by employing two internal capture[JMC16], external exhaust manifolds. The location of the two manifolds are placed above and below the upper and lower donor rolls respectively. The manifolds are mounted in a position to improve emissions control as well as reductions in the flow needed to accomplish the task The upper and lower manifolds are able to control the loose toner emitted by the housing and lower powder cloud, they cannot collect the toner released by the upper powder cloud. To prevent toner accumulation in the middle regions of the wire module, a manifold is incorporated as an integral part of the wire module frame.

Abstract: A developer unit for developing a latent image recorded on an image receiving member with marking particles, to form a developed image. A donor member is spaced from the image receiving member and adapted to transport marking particles to a development zone adjacent the image receiving member. An electrode is positioned in the development zone between the image receiving member and the donor member. A voltage supply is provided for electrically biasing the electrode during a developing operation with an alternating current bias to detach marking particles from the donor member, forming a cloud of marking particles in the development zone, and developing the latent image with marking particles from the cloud. The voltage supply periodically electrically biases the electrode during a cleaning operation with a direct current bias and with a alternating current bias so that toner is effectively removed from the wire. The bias levels are chosen to reduce field induced redeposition of right or wrong sign toner.

Abstract: In an electrostatographic imaging apparatus employing at least one charging device, in an electrostatic charge process involving the creation of latent electrostatic images, A method for controlling corona current generation by said at least one charging device is disclosed. The method comprising the steps of: generating an AC current and an AC voltage with a power supply; measuring the steady state negative half cycle of current, filtering capacitive current spikes from said negative half cycle current measurement and generating a corona current feedback signal in response to said filtering step; and dynamically adjusting the AC voltage in response to the corona current feedback signal so that the steady state negative half cycle of current measured in said measuring step remains constant.

Abstract: A development system is disclosed including a developer roll adapted for depositing developer material on an imaging surface having an electrostatic latent image thereon. The development system which includes a developer roll with a magnetic sleeve having a static magnetic field pattern for transporting developer material to a development zone. In operation the stationary magnetically patterned sleeve holds a thin well-defined blanket of magnetic developer on the sleeve surface. Magnetic assembly rotates and thereby generating a tangential magnetic field to move the developer blanket along the surface of sleeve; The developer blanket passes over zones on sleeve where developer material is picked up, self metering, mixing, blanket homoginization, tribo charging and developer transport occurs. The developer blanket moves to the development zone which is defined by a planar portion on the sleeve; parallel and adjacent to the imaging surface whereupon the blanket is compressed.

Abstract: Special stochastic screens are generated to eliminate the moire between stochastic screens and checkerboard inputs. Using the checkerboard pattern, we can divide the entire stochastic screen S into two subsets: S.sub.1 is defined by all pixels, which lie on the white half of the checkerboard, and S.sub.2 is by the black half. The design of a stochastic screen is a mathematical optimization process, which as a single-value merit function as Q(S), so the design process can be described as maximizing Q(S). To eliminate the moire between the checkerboard input and the stochastic screen, the same design criteria to the two subsets, S.sub.1 and S.sub.2, individually, as well as to the entire set S is applied.

Abstract: An apparatus for monitoring and controlling electrical parameter of an imaging surface, the monitoring controlling apparatus including a patch generator for recording a first control patch at a first voltage level and a second control patch at a second voltage level on the imaging surface; electrostatic voltmeter for measuring voltage potentials associated with the first control patch and second control patch. A processor, in communication with the patch generator, calculates the electrical parameters of the imaging surface from the measured voltage potentials from the first and second control patches. The processor determines a deviation between the calculated electrical parameters values and setup values. Then, the processor produces and sends a feedback error signal to the patch generator if the deviation exceed a threshold level. The patch generator records a third control patch at a third voltage level on the imaging surface upon reception of the error signal. The ESV senses the third control patch.

Abstract: A color marking machine which produces a composite color image in five cycles of a photoreceptive member, said color marking machine including a continuous photoreceptive member; a drive system rotating said photoreceptive member in a first direction; a charging station (R) for charging said photoreceptive member; an exposure station (E) for exposing said photoreceptive member so as to produce latent images on said photoreceptive member; a development station (D) for developing said latent images with toner to produce a toner image on said photoreceptive member; a transfer station (T) for transferring said toner image from said photoreceptive member onto a substrate; and a cleaning station (C) for removing residual toner particles from said photoreceptive member; and an camming assembly, operatively connected to said cleaning station and said transfer station, for engaging and disengaging said cleaning station and transfer station to and from said photoreceptive member.

Abstract: An electrophotographic printing machine of the type in which an electrostatic latent image recorded on a charge retentive surface is developed with toner particles to form a visible image thereof, including; a housing having a supply of toner and developer therein; a donor member for transporting toner from the housing to the development zone; a means for conveying toner to the donor member; blower for generating a negative air stream for carrying toner therein; and a filter for removing the toner from the negative air stream, the filter including filter material and spring blower, connected thereto, for oscillating the filter material to dislodge toner material collected in the filter when the generating means is disabled.

Abstract: An apparatus for forming an image on a recording sheet having low toner pile height is disclosed. A latent image is formed on an imaging member. A developer unit develops the latent image with a less than monolayer of toner particles on the imaging member. The developed image is transferred to a compliant intermediate member whereupon a filming station spreads the toner particles to form a film layer. The station includes a heater for heating the less than monolayer of toner particles to a temperature sufficient to cause the toner particles present on the intermediate member to soften; and a roller for spreading the less than a monolayer of toner particles to generate the thin film layer. The above process is repeated for subsequent colored toners to produce a multi film layer color image. Thereafter, the multi film layer color image is transferred from the intermediate member onto a recording sheet.

Abstract: An electrophotographic printing machine of the type in which an electrostatic latent image recorded on a charge retentive surface is developed with toner particles to form a visible image thereof, including; a housing having a supply of toner and developer therein; a donor member for transporting toner from said housing to the development zone; means for conveying toner to the donor member; means for generating a negative air stream for carrying toner therein; and a filter for removing the toner from the negative air stream, said filter including filter material and oscillation means, operational connected to said conveying means, for oscillating said filter material to dislodge toner material collected in said filter when said generating means is disabled.

Abstract: A developer unit for developing a latent image recorded on an image receiving member with marking particles, to form a developed image, including an image receiving member moving at a predetermined process speed. A donor member is spaced from the image receiving member and adapted to transport marking particles to a development zone adjacent the image receiving member. An electrode is positioned in the development zone between the image receiving member and the donor member. A voltage supply to electrically bias the electrode during a developing operation with an alternating current, to detach marking particles from the donor member, forming a cloud of marking particles in the development zone, and developing the latent image with marking particles from the cloud. A modulator, responsive to the predetermined process speed, controls a modulation rate of the voltage supply to minimize harmonic resonant vibrations of the electrode.

Abstract: An apparatus for developing a latent image recorded on a surface, including; a housing defining a chamber storing at least a supply of toner therein; a donor member spaced from the surface and adapted to transport toner from the chamber of the housing to a development zone adjacent the surface; a plurality of electrodes longitudinally disposed on the donor member; and a commutator brush contacting the electrodes along a portion of the circumference of the donor member, said commutator brush including means for generating pneumatic force to move said commutator brush into contact with the electrodes.

Abstract: There is provided document stacking stacker for stacking documents exiting a wide format machine, including a sheet tray having a planar base plate for stacking sheets thereon and a side wall for abutting sheets thereagainst; guides disposed adjacent the tray to direct sheets therein at an angle relative to the plane of the base plate, a feeder associated with the guides to feed sheets through the guides into the tray; a corrugating bar includes an array air corrugaters, the air corrugators are connected to an air plenum, each of the air corrugators have an air discharge ports for discharge of air against incoming bottom surface of sheets in the direction of movement of the sheets to corrugated the sheets as the sheet is feed to the tray.

Abstract: An apparatus and method for enhancing toner charge level in a hybrid scavengeless development system. The system includes a housing defining a chamber storing a supply of developer material including toner; a toner donor member spaced from the surface and being adapted to transport toner to a region opposed from the surface; A mag roll conveys the developer material in the chamber of the housing onto a region of the donor member; A charging device ion charges the toner loaded on the region of the donor member; and an electrode member space near the surface of the donor member being electrically biased by a power supply to detach toner from the donor member as to form a toner cloud for developing the latent image.

Abstract: An apparatus and method for non-interactive, dry powder development of electrostatic images including: an image bearing member bearing an electrostatic image; two component developer including toner and permanently magnetized carrier beads, the carrier having average diameter (2a) and magnetization M.sub.b a developer transporting member having a thickness t for transporting a developer layer of the two component developer, the layer spaced close to and out of contact with the image bearing member, and wherein the developer layer is substantially without chains of carrier beads, a multipole magnet member disposed in close proximity behind the transporting member and moving relative to it so as to sweep poles across its surface, the magnet member having a periodic magnetization of spatial frequency k and a peak magnetization M.sub.0wherein M.sub.b, t, k, and M.sub.0, are chosen such that M.sub.b is sufficiently large to prevent the escape of developer, and a quantity ##EQU1## is greater than about 1/3.

Abstract: A developer unit for developing a latent image recorded on an image receiving member with marking particles, to form a developed image, including: a drive mechanism for moving the surface of the image receiving member at a predetermined process speed. A donor member is spaced from the image receiving member and adapted to transport marking particles to a development zone adjacent the image receiving member. A plurality of wires having a predefined tension are positioned in the development zone between the image receiving member and the donor member. A voltage supply to electrically bias the plurality of wires during a developing operation with an alternating current, to detach marking particles from the donor member, forming a cloud of marking particles in the development zone, and developing the latent image with marking particles from the cloud.

Abstract: The present invention is an apparatus that develops a latent image recorded on a surface with toner. An electrically biased electrode member in the development zone between the photoconductive member and the donor roll detaches toners from the donor roll so as to form a toner powder cloud in the development zone. The electrical bias applied on the donor member is an asymmetrical wave. Toner from the toner powder cloud develops the latent image.