Xerox Corporation

Frank C Genovese

James W Lannom

Robert W Anderson

Joel M Pollack

Eric Peeters

John Richard Andrews

Joel A Kubby

Dan A Hays

Stephen F Pond

Richard F Bergen

Mark Steven Amico

Steven B Bolte

Oscar G Hauser

Thomas E Orlowski

Raymond W Stover

Lawrence M Hart

Jinkuang Chen

A transport system for transporting sheet media in an image transport apparatus. The transport system comprises a drive section, and at least one wheel drivingly connected to the drive section. The wheel is disposed to contact the sheet media for transporting the sheet media generally in a process direction in the image transport apparatus, when the wheel is driven by the drive section. The wheel is steerable. The wheel is steered for orienting the wheel in a predetermined direction and for controlling a direction of travel of the sheet media relative to the process direction.

Photoreceptor belt drive system

An electrostatic recording medium includes a charge retentive layer located on a conductive substrate. An image recording surface on the charge retentive layer includes an array of discrete, conductive segments present in the image recording surface. A multiple electrode assembly having an array of recording electrode tips may be aligned for engagement with the image recording surface. Relative movement between the recording head and the electrostatic recording medium may be provided in such a manner that certain members of the recording electrode tips momentarily achieve Ohmic contact with respective elements of the discrete conductive segments present in the image recording surface. A latent image may be created in the electrostatic recording medium as the charge retentive layer receives an imagewise pattern of localized, discrete charges according to a variable voltage potential present at the tips of the recording electrode during the respective moments of Ohmic contact. The electrostatic latent image may then be made visible by operation of a developer station.

Method and apparatus for electrostatographic printing utilizing an electrode array and a charge retentive imaging member

A raster output scanner in which both the start-of-scan and the beam intensity of a laser beam are determined using a single photodetector. The raster output scanner has a laser source for generating a laser beam; a rotating polygon for sweeping the laser beam along a scan line plane, an optical fiber with a light receiving end positioned at a known position in the scan line plane and which intercepts at least a portion of the sweeping laser beam, and a photodetector for converting the intercepted laser beam into a beam current. The raster output scanner further includes both a scan detection circuit for producing a star-of-scan signal from the beam current and a beam intensity circuit for producing an electrical output which depends upon the magnitude of the beam current.

Single sensor laser beam synchronizer and intensity regulator

A magnetically actuated ink jet printing device for use in an ink jet printer ejects ink droplets by deforming a diaphragm with the force generated on an electrode in a magnetic field when an electric current pulse is applied thereto. In one embodiment, the diaphragm of the device is provided by anisotropically etching a silicon substrate with an etch stop which provides a thin membrane of silicon material for use as the diaphragm. An electrode having an input and output terminal is patterned over the diaphragm and a sacrificial layer is deposited over the silicon substrate surface containing the diaphragm. The sacrificial layer is patterned to subsequently provide the ink ejection chamber over the diaphragm. A patternable layer is deposited over the silicon substrate surface including the sacrificial layer and patterned to provide the nozzles and expose the electrode terminals. The sacrificial layer is removed and an ink supply is connected to the space previously occupied by the sacrificial layer. Magnetic field generating means having a predetermined magnetic field strength are placed adjacent the device, and electric current applied to the electrode terminals in a predetermined direction relative to the magnetic field produces a force necessary to deform the diaphragm and eject an ink droplet from the nozzles of the printing device.

Magnetically actuated ink jet printing device

An imaging system having a raster output scanner that produces high quality scan lines comprised of evenly spaced pixels. The raster output laser device is modulated in accordance with a variable frequency pixel clock that is derived from a high frequency oscillator using a dual modulus programmable divider that is controlled by a state machine. In turn, that state machine is controlled by information stored in a memory. The variable frequency pixel clock compensates for scan line nonlinearity, polygon facet errors, and/or scan line magnification.

Method and apparatus for controlling a pixel clock in a rotating polygon

A development system is which includes a developer roll with a magnetic sleeve. The sleeve has a static magnetic field pattern for transporting developer material to a development zone; and a magnetic system for generating a superimposed alternating magnetic field to agitate developer material in the development zone in order to produce a charged toner cloud intended for the non-interactive development of latent electrostatic images.

Magnetic sleeve for non-interactive agitated magnetic brush development

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. Agitation generated by the rotating magnetic assembly dislodges toner particles from the carrier beads and an AC field is applied to the sleeve to aid in the formation of a toner cloud in the development zone for transporting toner to the imaging surface by the development fields.

In a raster output scanning apparatus including a laser diode adapted to output a writing beam, a reflex circuit controls the laser diode. A sensor diode is positioned to receive a portion of light flux from the laser diode while the laser diode emits the writing beam to expose one pixel area on a photosensitive surface. An accumulator associated with the sensor diode accumulates charge created by the sensor diode resulting from light flux from the laser diode. A comparator associated with the accumulator monitors charge accumulated on the accumulator and arrests the source of light flux when the charge accumulated on the accumulator reaches a predetermined threshold level.

Pixel exposure control for a raster output scanner in an

A donor roll for transporting marking particles to an electrostatic latent image recorded on a surface is provided. The donor roll is adaptable for use with an electric field to assist in transporting the marking particles from the donor roll to a development zone adjacent the surface. The donor roll includes a rotatably mounted body and a first electrode member mounted on the body. The donor roll further includes a second electrode member mounted on the body and spaced from the first electrode member and a resistive member electrically interconnecting the first electrode member and the second electrode member so that when an activation potential for creating an electric field is applied to the first electrode member a portion of the potential will be transferred to the second electrode member creating an attenuated field.

Single-ended symmetric resistive ring design for sed rolls

A development system is disclosed including a developer transport adapted for depositing developer material on an imaging surface having an electrostatic latent image thereon, said developer transport including a core; a magnetic transport member rotating about said core wherein said magnetic transport member has a static magnetic field pattern for transporting developer material to a development zone; and a magnetic system for generating a superimposed alternating magnetic field to agitate developer material in said development zone.

Apparatus and method for non interactive agitated magnetic brush

An apparatus and method for controlling the modulation of an exposing beam of a rotating polygon type image forming apparatus using control marks formed on a rotating surface portion of a polygon member or a motor polygon assembly. The control marks are read by a reader during rotation of the polygon member, and the information read from the control marks is used to control the modulation of the exposing beam of the image forming apparatus to expose evenly spaced, uniformly sized, precisely oriented, geometrically straight scan lines of pixels on a photosensitive member. The control marks can include pixel clock information, intensity correction information, error correction information about individual facets of the polygon member, and motor speed control information.

Method and apparatus for controlling the modulation of light beams in a

A development system is which includes a flexible belt having a magnetic surface. The belt has a static magnetic field pattern for transporting developer material to a development zone; and a magnetic system for generating a superimposed alternating magnetic field to agitate developer material in the development zone in order to produce a charged toner cloud intended for the non-interactive development of latent electrostatic images.

Magnetic flexible belt for non-interactive agitated magnetic brush

A raster output scanner for use in an electrophotographic printer uses two light sources to create two scan lines on a photoreceptor simultaneously. The two light sources are operated in an alternating fashion, and the intensity of the light sources is monitored by a single sensor. The sensor is associated with a reflex-based exposure control system, which operates to shut off a particular light source when the exposure created by the light source reaches a threshold level.

Dual-beam, reflex-controlled laser circuit for an electrophotographic

A fiber optic detection system is used in a color reproduction device to generate color image registration signals. In one embodiment a retroreflector is positioned beneath the photoreceptor belt, the retroreflector being periodically visible through holes formed in a non-image area of the belt. An optical fiber directs flux from a light source onto the photoreceptor belt and periodically illuminates the retroreflector. Light is preferentially reflected back into the fiber with a portion being coupled to a photosensor to provide a signal used for registration purposes. In another embodiment, a plurality of optical fibers are bundled together to form a trunk at the belt illumination end with two branches functioning as the light input and detecting ends. In a still further embodiment, retroreflective marks are formed directly on the surface of a photoreceptor; the several fiber optic embodiments are used to detect the formed marks.

Fiber optic registration mark detection system for a color reproduction

A technique for achieving both start-of-scan detection and dynamic beam intensity regulation in a multiple laser beam raster output scanner using a single photodetector. The raster output scanner includes a source or sources of a plurality of laser beams, a rotating polygon having at least one reflecting facet for sweeping the laser beams to form a scan line path, and a photodetector for receiving illumination from the multiple laser beams and for converting those beams into beam-dependent electrical currents. The raster output scanner further includes a scan detection circuit for producing a start-of-scan signal from the beam dependent current, and a beam intensity circuit for producing an electrical output signal which depends upon the difference in beam intensity of at least two of the laser beams. Beneficially, the raster output scanner also includes an optical fiber that collects a portion of the light flux in the sweeping laser beams which directs the light flux onto the photodetector.

Growing community of inventors

Fairport, NY, United States of America

Frank C Genovese