Patents by Inventor Douglas K. Howell

Douglas K. Howell 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).

  • Optical monitor for imaging device filter
    Patent number: 6647224
    Abstract: A device for monitoring the status or condition of a filter element for an imaging device which employs an optical sensing device to monitor a concentration of toner particles. In one embodiment, the optical sensing device monitors a concentration of toner particles captured in a filter element within an electrostatic imaging device. The optical sensing device is connected to an imaging device controller. An output connected to the controller displays data representative of a degree to which the filter element is clogged by toner particulate.
    Type: Grant
    Filed: January 31, 2002
    Date of Patent: November 11, 2003
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Bruce L. Johnson, Bradley J. Anderson, Douglas K. Howell
  • Optical monitor for imaging device filter
    Publication number: 20030142992
    Abstract: A device for monitoring the status or condition of a filter assembly for an imaging device which employs an optical sensing device to monitor a concentration of toner particles. In one embodiment, the optical sensing device monitors a concentration of toner particles captured in a filter assembly within an electrostatic imaging device. The optical sensing device is connected to an imaging device controller. An output connected to the controller displays data representative of a degree to which the filter element is clogged by toner particulate.
    Type: Application
    Filed: January 31, 2002
    Publication date: July 31, 2003
    Inventors: Bruce L. Johnson, Bradley J. Anderson, Douglas K. Howell