Patents by Inventor Qi C. Xu

Qi C. Xu 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).

  • Frequency agile sonic transducer
    Patent number: 5166907
    Abstract: A solid-state tunable transducer has been developed by incorporating an elastically nonlinear material, silicone rubber, into an electroacoustic transducer made from piezoelectric ceramics. The resonant frequency and mechanical Q of the transducer are tuned mechanically by applying a uniaxial compressive stress to the composite. The resonant frequency is tuned electrically by placing a piezoelectric actuator into the composite and varying the magnitude of the d.c. bias.
    Type: Grant
    Filed: June 24, 1991
    Date of Patent: November 24, 1992
    Assignee: The Pennsylvania Research Corporation
    Inventors: Robert E. Newnham, Qi C. Xu, Michael Blaszkiewicz