Patents by Inventor Patrick J. Marshall

Patrick J. Marshall 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).

  • Oscillatory resonant transducer driver circuit
    Patent number: 4418297
    Abstract: A transducer driver circuit is disclosed in which a pair of transistors and a pair of transformers are connected together to drive an ultrasonic cleaning apparatus.
    Type: Grant
    Filed: April 20, 1983
    Date of Patent: November 29, 1983
    Assignee: L & R Manufacturing Company
    Inventor: Patrick J. Marshall
  • Document-marking machine
    Patent number: 3958270
    Abstract: Machine for marking documents with visually readable printed information on one portion of the document, and with magnetically encoded information on another, magnetizable portion of the document. The magnetically encoded information is read to determine if it was recorded with an error. If it was, printing is prevented so that a document which has an error in the magnetically recorded information is presented as a blank, non-printed document. It is therefore readily apparent that the document is defective and should not and cannot be used.
    Type: Grant
    Filed: December 20, 1971
    Date of Patent: May 18, 1976
    Assignee: Litton Business Systems, Inc.
    Inventors: Richard C. Graniere, Patrick J. Marshall