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. 15, 2009
Filed:
Aug. 20, 2004
Applicant:
Darwin Mitchel Hanks, Fort Collins, CO (US);
Inventor:
Darwin Mitchel Hanks, Fort Collins, CO (US);
Assignee:
Hewlett-Packard Development Company, L.P., Houston, TX (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B 7/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A control circuit creates a self-sensing active-damping voice coil. The control circuit includes a current sensor coupled to a voice coil. A first filter is coupled to the current sensor to create an error voltage that is proportional to the integral of an external acceleration applied to the voice coil. A second filter with a lead-lag component is coupled to the error voltage to create a voltage applied to the voice coil that substantially cancels the external acceleration below a pole defined by a lead-lag component thereby damping the external accelerations.