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. 27, 2003
Filed:
Jun. 30, 2000
John Jay Freeman, Longmont, CO (US);
Seagate Technology LLC, Scotts Valley, CA (US);
Abstract
A method and system for driving a phase of an electrical motor are disclosed. The method and system detect the back electromotive force being generated by a coil. The back electromotive force is amplified or attenuated to a level necessary to drive the motor at a desired speed and is fed back into the coil. The detected back electromotive force signal that drives the motor is proportional to, in phase with, and at the same frequency as the back electromotive force signal being generated by the coil. Using the back electromotive force to produce the drive signal permits autosynchronization of the drive signal without use of position sensors and reduces acoustic noise and velocity modulation associated with sudden torque shifts.