Patents by Inventor John D. McCaffrey

John D. McCaffrey has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7493060
    Abstract: In a xerographic printing apparatus, a charge device is used to apply a charge to a photoreceptor. The charge device includes a wire. A shuttle moves along the charge device, and includes a brush wherein the sides of the bristles contact the wire. When the brush moves along the wire, an accumulation of stray particles on the wire is made relatively smooth.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: February 17, 2009
    Assignee: Xerox Corporation
    Inventors: David Sekovski, Robert A. Gross, John D. McCaffrey, Michael N. Soures, David K. Ahl, Douglas A. McKeown, Michael G. Petranto
  • Patent number: 7412186
    Abstract: In a xerographic printing apparatus, a charge device is used to apply a charge to a photoreceptor. The shuttle includes a wiper that cleans a sidewall of the charge device. A tab is disposed adjacent the sidewall to retain toner or dirt accumulated by the scraper. The tab is electrically insulative, and effectively covers the accumulated toner or dirt, to lower the possibility of arcing within the charge device.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: August 12, 2008
    Assignee: Xerox Corporation
    Inventors: David Sekovski, Robert A. Gross, John D. McCaffrey, Michael N. Soures, David K. Ahl, Douglas A. McKeown, Michael G. Petranto
  • Patent number: 6963708
    Abstract: A charging system for uniform charging of charge retentive surfaces such as photoreceptors in imaging systems. The charging system includes corona producing elements and grid elements such as scorotron screens wherein the grid elements are arranged generally parallel to each other and have differentiated grid feature patterns. The differentiated grid feature patterns enable more uniform charging.
    Type: Grant
    Filed: September 4, 2003
    Date of Patent: November 8, 2005
    Assignee: Xerox Corporation
    Inventors: David Sekovski, Paul F. Sawicki, John D. McCaffrey
  • Patent number: 6459873
    Abstract: In DC pin scorotron charging apparatus for charging a photoreceptor to a final voltage, a first DC pin scorotron charging device initially charges the photoreceptor to an intermediate overshoot voltage and a second DC pin scorotron charging device thereafter uniformly charges the photoreceptor to the final voltage. The first DC pin scorotron charging device provides a generally high percent open control grid area, a generally high emitter slope, and a generally high emitter pin current. The second DC pin scorotron charging device provides a generally low percent open control grid area, a generally low emitter slope, and a generally low emitter pin current.
    Type: Grant
    Filed: November 15, 2000
    Date of Patent: October 1, 2002
    Assignee: Xerox Corporation
    Inventors: Jing Qing Song, John F. Obrien, David Sekovski, Robert K. Fox, John D. McCaffrey, Jeffrey W. Drawe