Patents by Inventor William D. Cragg

William D. Cragg 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).

  • Piezoelectric high polymer, multilayer electro-acoustic transducers
    Patent number: 4186323
    Abstract: The present invention provides an electro-acoustic transducer including a pair of piezo-electric plastics film diaphragms coupled in a push-pull manner and so arranged as to form a lens-like configuration by a body of a light fibrous material therebetween.The diaphragms are coupled in push-pull manner, and the transducer is especially suitable for use in a telephone instrument.
    Type: Grant
    Filed: September 16, 1977
    Date of Patent: January 29, 1980
    Assignee: International Standard Electric Corporation
    Inventors: William D. Cragg, Anthony N. Lawson