Patents by Inventor Dave W. Johnson

Dave W. Johnson 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).

  • Adjustable and self-holding supply roll system for plotting devices
    Patent number: 5458310
    Abstract: This is a system for holding a supply roll of media in a plotter or the like. One support bar is of fixed length and has a sliding lockable collar for use with different widths of media. Another support bar is of adjustable length for use in plotters employing different widths of media. The end holder for the support bar includes a biased member holding the end in a U-shaped slot to resist lifting from forces on the supply roll as the media is removed.
    Type: Grant
    Filed: December 8, 1993
    Date of Patent: October 17, 1995
    Assignee: Calcomp Inc.
    Inventor: Dave W. Johnson
  • Plot handling apparatus
    Patent number: 5459493
    Abstract: This is a pair of improvements for a plot rolling mechanism for a pen plotter or the like having a rolling mechanism with an entry opening and a receiving bin for receiving rolled plots. The first improvement comprises a sealing mechanism for sealing the entry opening during plotting, the sealing mechanism being rotatable between a sealing position blocking the entry opening and a retracted position not blocking the entry opening and apparatus for rotating the sealing mechanism between the sealing position and the retracted position.
    Type: Grant
    Filed: December 8, 1993
    Date of Patent: October 17, 1995
    Assignee: Calcomp Inc.
    Inventor: Dave W. Johnson