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:
Aug. 26, 1980
Filed:
Mar. 18, 1977
Cormac G O'Neill, Lafayette, CA (US);
Charles E Foster, Fremont, CA (US);
Physics International Company, San Leandro, CA (US);
Abstract
An electromotive actuator comprises a hollow cylinder within which is an electroexpansive body having attached to each end a metal cup with slotted sides. Inside of each cup there is positioned an electroexpansive disc which, in the absence of excitation, causes the slotted sides, which are called fingers hereinafter, to bend outward, and in the presence of excitation enables them to return to their original position. In the absence of excitation the fingers clamp tightly against the inner surface of the cylinder and in the presence of excitation they spring inwardly and release that surface. By sequencing the excitation of the respective discs and the central body in one embodiment of the invention, the assembly can be made to move in either direction and thereby move an externally extending rod. In another embodiment of the invention, by properly sequencing the excitation of the discs and central body, high torque and fine angular resolution may be obtained.