The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 11, 2001
Filed:
Apr. 30, 1999
James S. Vartuli, Princeton, NJ (US);
David L. Milius, Cranbury, NJ (US);
Xiaoping Li, Bensalem, PA (US);
Wei H. Shih, Rosemont, PA (US);
Wan Y. Shih, Rosemont, PA (US);
Robert K. Prud'homme, Princeton Junction, NJ (US);
Ilhan A. Aksay, Princeton, NJ (US);
The Trustees of Princeton University, Princeton, NJ (US);
Abstract
A modification of the traditional unimorph flextensional actuator is provided by replacing the metal shim with an electrically conducting oxide. Comprised of lead zirconate titanate and zinc oxide that is co-sintered, the laminate composite obtains large axial displacements while maintaining moderate axial loads. The varistor properties of zinc oxide dictate that the conductance increases several orders of magnitude when a critical electric field is applied. The versatility of the processing over other actuator system facilitates miniaturization, while maintaining comparable performance characteristics. Functional gradients in the material properties are created in the green body by layering thin tape cast sheets. The unique PZT-zinc oxide composite not only controls the piezoelectric gradient, but permits control of the sintering kinetics leading to the processing of either flat or highly domed structures.