Patents Represented by Attorney John J. McArdle, Jr.
  • Patent number: 6650352
    Abstract: The write lines of a color laser printer are maintained substantially equal throughout the printer's operation by an electronic control arrangement. At the factory, the write lines on all photoconductors of the color laser printer are calibrated to be substantially equal, and the ratio of each write line to a measuring line for each photoconductor is ascertained. During operation of the printer, the length of each of the measuring lines is periodically determined through counting the number of PELslice clock timing pulses produced from a PELslice clock operating at a fixed frequency determined during factory calibration. The length of the write line is determined by the product of the length of the measuring line and the factory calibrated ratio of the length of the write line to the length of the measuring line.
    Type: Grant
    Filed: November 13, 2001
    Date of Patent: November 18, 2003
    Assignee: Lexmark International, Inc.
    Inventors: Daniel Eugene Pawley, David Anthony Schneider, Thomas Campbell Wade, Earl Dawson Ward, II
  • Patent number: 6567633
    Abstract: An improved intermediate belt system (ITM module) is provided, which controls the lateral motion of the belt in the scan direction of an EP printer, without the use of edge reinforcements or other attachments added to the belt. The tracking system of this ITM module is passive, and maintains roll alignment/parallelism within a predetermined tolerance while also maintaining roll conicity-end flare to a predetermined maximum diametral variation over the roll to minimize the effect of external forces on the belt walk rate. The ITM module also provides angled tracking guides near the tension roll to control the lateral position of the belt; the position of these tracking guides is adjustable at time of manufacture to achieve the desired lateral belt position.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: May 20, 2003
    Assignee: Lexmark International, Inc.
    Inventors: Robert Leonard Burdick, Mark Andrew Omelchenko, Stacy Marie Pargett, Harald Portig
  • Patent number: 6387719
    Abstract: The invention provides a method for improving adhesion between a polymeric planarizing film and a semiconductor chip surface. The method includes deposition resistive, conductive and/or insulative materials to a seimconductor chip surface to provide a semiconductor chip for an ink jet printer. The chip surface is treated with a dry etch process under an oxygen atmosphere for a period of time and under conditions sufficient to activate the surface of the chip. A polymeric planarizing film is applied to the activated surface of the semiconductor chip. As a result of the dry etch process, adhesion of the planarizing film is increased over adhesion between the planarizing film and a semiconductor surface in the absence of the dry etch treatment of the chip surface.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: May 14, 2002
    Assignee: Lexmark International, Inc.
    Inventors: James Michael Mrvos, Carl Edmond Sullivan
  • Patent number: 6362847
    Abstract: The write lines of a color laser printer are maintained substantially equal throughout the printer's operation by an electronic control arrangement. At the factory, the write lines on all photoconductors of the color laser printer are calibrated to be substantially equal, and the ratio of each write line to a measuring line for each photoconductor is ascertained. During operation of the printer, the length of each of the measuring lines is periodically determined through counting the number of PELslice clock timing pulses produced from a PELslice clock operating at a fixed frequency determined during factory calibration. The length of the write line is determined by the product of the length of the measuring line and the factory calibrated ratio of the length of the write line to the length of the measuring line.
    Type: Grant
    Filed: June 15, 1999
    Date of Patent: March 26, 2002
    Assignee: Lexmark International, Inc.
    Inventors: Daniel Eugene Pawley, David Anthony Schneider, Thomas Campbell Wade, Earl Dawson Ward, II
  • Patent number: 6363228
    Abstract: A method and apparatus for providing transfer quality optimization in printers is disclosed. A transfer belt subassembly includes a transfer belt and a storage device. The transfer belt also includes a home position indicator. The transfer belt subassembly is measured and characterized relative to the home position indicator before being installed in a printer. The measurement and calibration data for the transfer belt is then stored in the storage device that is part of the transfer belt subassembly. When the transfer belt subassembly is inserted into a printer, a controller within the printer is placed in communication with the storage device. A sensor is used to determine the home position of the transfer belt from the indicator, and a resulting signal indicating when the belt is at the home position is provided to the controller.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: March 26, 2002
    Assignee: Lexmark International, Inc.
    Inventor: Gregory Lawrence Ream
  • Patent number: 6359640
    Abstract: A method and apparatus provides for minimizing visual artifacts resulting from laser scan process direction position errors in an electrophotographic machine. The electrophotographic machine has a process direction, and includes a photoconductive member having an image forming surface having defined thereon a plurality of pixel locations which form a pixel grid, and wherein two adjacent pixels in the process direction are separated by a pixel spacing distance. A printhead unit has a first laser beam generator and a second laser beam generator, wherein the first laser beam generator generates a first laser beam which impinges the surface at a first location and the second laser beam generator generates a second laser beam which impinges the surface at a second location. The second location is spaced apart from the first location in the process direction by a separation distance equal to an integer multiple of the pixel spacing distance plus a distance less than the pixel spacing distance.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: March 19, 2002
    Assignee: Lexmark International, Inc.
    Inventors: Cary Patterson Ravitz, Thomas George Twardeck
  • Patent number: 6350553
    Abstract: A photoconductor comprises a substrate and at least one layer. The at least one layer is selected from the group consisting of charge transfer layers comprising a charge transfer molecule, polycarbonate and a first polyaryl ether selected from the group consisting of polyaryletherketones, poly(aryl-perfluoroaryl ether)s, polyaryletherketone-hydrazones, polyaryletherketone-azines and mixtures and copolymers thereof; charge generating layers comprising a pigment, a polyvinylbutyral and a second polyaryl ether selected from the group consisting of polyaryletherketones, polyarylethersulfones and mixtures and copolymers thereof; and mixtures thereof.
    Type: Grant
    Filed: January 23, 2001
    Date of Patent: February 26, 2002
    Assignee: Lexmark International, Inc.
    Inventor: Kasturi R. Srinivasan
  • Patent number: 6347197
    Abstract: An oil web system and method for operating a fuser system of an imaging apparatus in which remaining life of the oil web is determined from data on drive mechanism activation and data on web advancement lengths. A warning signal can be issued upon a predetermined remaining length being reached, and the machine can be disabled upon exhaustion of the web life.
    Type: Grant
    Filed: October 20, 2000
    Date of Patent: February 12, 2002
    Assignee: Lexmark International, Inc.
    Inventors: Michael David Maul, Edward Alan Rush, David William Shuman
  • Patent number: 6327458
    Abstract: A method of media-to-image registration sets a top writing line margin on a print medium within an electrophotographic machine. Movement of a substantially stationary sheet of print medium along a print medium path within the electrophotographic machine is initiated. An image associated with the sheet of print medium is scanned onto a developing unit. The scanning step commences before the initiating step. Toner is adhered to the image on the developing unit. The toner is transferred from the developing unit to a moving toner transfer medium. The electrophotographic machine is provided with a toner transfer area in which the toner can be transferred to the moving sheet of print medium. A speed of the movement of the sheet of print medium is adjusted such that the toner is transferred from the moving toner transfer medium to a desired area on the sheet of print medium within the toner transfer area.
    Type: Grant
    Filed: April 6, 2000
    Date of Patent: December 4, 2001
    Assignee: Lexmark International, Inc.
    Inventor: Danny Keith Chapman
  • Patent number: 6099101
    Abstract: The invention described in the specification relates to an apparatus and method for disabling an ink jet print head cartridge so that the disposable cartridge can not be refilled and used again. The method involves placing a monitoring and disabling device inside of the ink jet print head cartridge. When the print head has exceeded its useful life span, the disabling device disables the print head cartridge. The apparatus consists of a set of electrically charged capacitors, a small processor, ink sensors, and an extra long life miniature battery. A card containing the battery, processor and capacitors is placed in the ink jet print head cartridge. A sensor is placed in the bottom of each ink well of the cartridge. The processor periodically checks the level of ink in each inkwell. Once the processor determines that a specific inkwell has been empty for a certain period of time, the capacitors are discharged to the section of the nozzle plate corresponding to the expended inkwell.
    Type: Grant
    Filed: April 6, 1998
    Date of Patent: August 8, 2000
    Assignee: Lexmark International, Inc.
    Inventors: Giuseppe Andre Maurelli, Brant Dennis Nystrom, Jason Edward Singleton
  • Patent number: 6020978
    Abstract: A dispersed-dot stochastic dither array is provided for rendering halftone images having excellent visual quality and are created by a minimum density variance method. By minimizing the variance in the number of dots within each local region of the image, a smooth and dispersed distribution of dots may be obtained. For color printing, a separate threshold array is generated for each of the color planes, however, the stochastic screens are interlocked so that the threshold arrays are generated while considering the other color threshold arrays. In this manner, a blue noise distribution may be produced by the individual arrays as well as by any combination of the individual arrays. When generating a single threshold array for a color plane, a particular criterion is used to determine where the next threshold value should be located, and the selection of a threshold location in each array considers the criterion for all the threshold arrays being generated.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: February 1, 2000
    Assignee: Lexmark International, Inc.
    Inventors: Brian Edward Cooper, Shaun Timothy Love
  • Patent number: 5999705
    Abstract: A method of printing on a print medium with an ink jet printer uses a first color ink, a second color ink and a black ink. An image area on the print medium has a plurality of pixel locations. Print image data indicate one of a presence and an absence of the first color ink, the second color ink and the black ink at the plurality of pixel locations. A subset of the print image data is defined. A determination is made as to whether the subset of print image data indicates 1) a presence of the first color ink and/or the second color ink within the subset and a presence of the black ink within the subset; 2) a presence of each of the first color ink and the second color ink within the subset at a same corresponding pixel location; and/or 3) a presence of the first color ink and/or the second color ink within the subset at a number of corresponding pixel locations exceeding a threshold value. The print medium is printed on in the image area at an interlace level which is dependent upon the determination.
    Type: Grant
    Filed: April 15, 1998
    Date of Patent: December 7, 1999
    Assignee: Lexmark International, Inc.
    Inventors: John Booth Bates, Scott Michael Heydinger, Robert Frederick Locasto
  • Patent number: 5995772
    Abstract: A cartridge for an electrophotographic machine having a sump for carrying an agitator rotatably mounted in the sump for engagement with a toner; an encoded device coupled to a first end of the agitator; and a torque sensitive coupling connected to a second end of the agitator which is connectable to a drive mechanism of the machine. The encoded device includes coding representing cartridge characteristic information.
    Type: Grant
    Filed: December 17, 1996
    Date of Patent: November 30, 1999
    Assignee: Lexmark International Inc.
    Inventors: Raymond Jay Barry, Steven Alan Curry, Benjamin Keith Newman, Gregory Lawrence Ream, Earl Dawson Ward, II, Phillip Byron Wright
  • Patent number: 5966231
    Abstract: Compensation for beam separation of multiple laser beams of a laser printer simultaneously scanning a photoconductor drum is automatically made. The time for the lead beam to travel a predetermined distance is ascertained and then the separation time between the lead beam and one of the remaining beams is determined. When using only one light sensor, the time for the lead beam to travel the predetermined distance is the scan time of the lead beam. When using two light sensors, the time for the lead beam to travel the predetermined distance is the time for the lead beam to travel between the two light sensors, which define the predetermined distance, in the same scan. This determination of the time for the lead beam to travel the predetermined distance and its separation time from another of the remaining beams is continuously made for all of the remaining beams even during printing.
    Type: Grant
    Filed: August 7, 1998
    Date of Patent: October 12, 1999
    Assignee: Lexmark International, Inc.
    Inventors: Craig Palmer Bush, Philip Jerome Heink, David Kurt Klaffenbach, Thomas Campbell Wade
  • Patent number: 5956055
    Abstract: A method of printing with an ink jet printer compensates for skewed printing on a print medium. An image area is defined on the print medium which has a plurality of rows of pixel locations and a plurality of columns of pixel locations. A printhead includes a plurality of vertically adjacent ink emitting orifices arranged in an array having a height. The printhead is scanned during first and second scans across the print medium in directions transverse to the advance direction. The ink is jetted onto the print medium from the ink emitting orifices during the first and second scans at selected ink dot placement locations generally corresponding to one of the columns of pixel locations. An offset is determined in a transverse direction between a bottom ink dot placement location associated with the first scan and a top ink dot placement location associated with the second scan. The array of ink emitting orifices is segmented into at least two vertically adjacent segments of ink emitting orifices.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: September 21, 1999
    Assignee: Lexmark International, Inc.
    Inventors: Bruce David Gibson, Kent Lee Ubellacker, John Dennis Zbrozek
  • Patent number: 5938190
    Abstract: Disclosed is a replaceable media guide for use with a sheet feeding mechanism. The media guide includes a support plate, an edge guide projecting substantially at right angles from the support plate, and a first sheet engaging friction pad engaged with the support plate. The guide is designed so that the first friction pad faces a friction roller of a sheet feeding mechanism when the guide is mounted on the sheet feeding mechanism. A sheet feeding apparatus is also provided in which the media guide is inserted into the sheet feeding mechanism.
    Type: Grant
    Filed: May 31, 1996
    Date of Patent: August 17, 1999
    Assignee: Lexmark International, Inc.
    Inventors: Michael Clark Campbell, Edmund Hulin James, III, Christopher Patrick Murphy, David Kyle Murray
  • Patent number: 5905906
    Abstract: A networked system having a host computer and multiple printers with bi-directional communications capabilities is provided in which the setup (configuration) of one printer can be easily communicated to another printer, using NPAP messages. The host computer can be used by a Network Administrator to "read" the setup or configuration information inside each of the printers connected to the network that have the required NPAP bi-directional communications capability. This setup information, once communicated to the host computer, can be stored in a long-term memory, such as a hard disk drive, for future reference. The setup information can also be communicated to one or more printers connected to the network, and such printers can be configured by the setup information in which that information is used either as their initial setup information, or as a modified setup.
    Type: Grant
    Filed: August 7, 1997
    Date of Patent: May 18, 1999
    Assignee: Lexmark International, Inc.
    Inventors: Kevin Patrick Goffinet, Francis Darrell Rafferty, Jr., Gail Marie Songer, James Francis Webb, Jeffrey Keith Wedinger, Lloyd Phillip Young
  • Patent number: 5905852
    Abstract: Apparatus, system and method is provided in which a primary printer prepares print data for use by its resident print engine, or by an alternate printer. The primary printer includes subsystems for receiving original print data from a device, such as a computer or scanner, and for converting the original print data into a data format compatible with the alternate printer.
    Type: Grant
    Filed: February 16, 1996
    Date of Patent: May 18, 1999
    Assignee: Lexmark International, Inc.
    Inventors: Shaun Timothy Love, Bruce Alan Peltzer, Gregory John Sherwood, Steven Frank Weed
  • Patent number: 5877798
    Abstract: A laser printer is provided having an automatic printhead identification system for use in a family of laser printers that are compatible with more than one model of printhead. For example, a single laser printer model can be made so that two different printheads can be successfully used, so long as the printer system knows which laser printhead has actually been installed. To detect which printhead has been installed, the printer operating system provides a reference clock signal having a pre-determined frequency, which dictates the rotational speed of the motor. Once the motor has achieved a "lock" operational speed, the printer measures the scan rate of the faceted mirror by detecting the time interval between pulses of the "HSYNC" signal. The HSYNC signal is sent to a "divide-by-n counter" circuit which divides the pulse frequency of the HSYNC signal, thereby increasing the time interval (by a factor of "n") that must be sensed by the system to determine which printhead is in fact installed.
    Type: Grant
    Filed: March 21, 1997
    Date of Patent: March 2, 1999
    Assignee: Lexmark International Inc.
    Inventors: Cyrus Bradford Clarke, David Brian Langer, Phillip Byron Wright
  • Patent number: 5867203
    Abstract: A method of reducing EMI when printing an image with a printer having a laser includes determining edge pels located near an edge of the image, determining interior pels located within the image and not edge pels, forming edge pels by operating the laser at a first duty cycle and forming at least a portion of a plurality of interior pels by operating the laser at a second duty cycle longer than the first duty cycle. Another aspect is a method of reducing EMI in a printer when forming a latent image on a photoconductive member by gating a light source ON and OFF, including the steps of identifying a first region near an edge of an image to be formed, the first region being formed by gating the light source at a first frequency; and identifying an interior region of the image to be formed, the interior region being formed by gating the light source at a second frequency lower than the first frequency.
    Type: Grant
    Filed: May 16, 1997
    Date of Patent: February 2, 1999
    Assignee: Lexmark International Inc.
    Inventors: Christopher Dane Jones, Gary Scott Overall, Thomas Campbell Wade, Phillip Byron Wright