Patents by Inventor James Elwood Kerr

James Elwood Kerr 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: 5923346
    Abstract: In an electrostatic ink jet printer, all nozzles of a printhead are spaced generally the same distance from a moving paper print substrate. Three voltage levels are selectively applied to each nozzle of the printhead. As the paper moves past the printhead, a bias voltage Vb is applied to all nozzles which have a static protruding meniscus which shape is determined by a balance between the internal pressure, surface tension, and bias voltage. When the paper arrives at a print row, nonprinting nozzles have a shadow voltage pulse Vs, the "shadow pulse," applied thereto, and printing nozzles have a higher magnitude print pulse Vp applied thereto. The magnitude of the shadow pulse Vs causes an additional excursion of the ink meniscus to form at each non-printing nozzle. The higher magnitude of print pulse Vp causes an ink filament to move from a printing nozzle to the paper.
    Type: Grant
    Filed: October 23, 1995
    Date of Patent: July 13, 1999
    Assignee: imaging Technology international
    Inventors: Ross Neal Mills, James Elwood Kerr, Jon-Christophe Bernard Febvre