Patents Examined by Al Dudding
  • Method of driving an ink jet printhead
    Patent number: 6431675
    Abstract: Disclosed is a method of driving an ink jet printhead having flexural or longitudinal vibration mode piezoelectric elements. The method includes a contracting step for expanding the pressure generating chamber until a velocity of the trailing edge of the ejected ink drop is substantially zero at a position near the nozzle orifice. The printhead ejects an ink drop having small volume without a reduction in ink drop velocity.
    Type: Grant
    Filed: April 5, 1999
    Date of Patent: August 13, 2002
    Assignee: Seiko Epson Corporation
    Inventor: Junhua Chang