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:
May. 06, 1997
Filed:
Jul. 06, 1994
Robert E Head, Tempe, AZ (US);
McDonnell Douglas Corporation, Huntington Beach, CA (US);
Abstract
A piezoelectric actuator includes a plurality of linearly axially expandable hard piezoelectric rods located between two plates and are distributed about a central twistable core fastened between the plates, with the axis of the rod skew to the axis of the core, resembling a squirrel cage. The actuator produces a twisting movement between the plates, responsive to voltage induced expansion of those piezoelectric rods. Fly by Wire aircraft control is realized with the actuator in various systems providing all electric control of aerodynamic surfaces, including an electronic helicopter swashplate by which the effective pitch of the main rotor blade is controlled.