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. 12, 2003
Filed:
Apr. 17, 2001
Tak Koon Ooi, Singapore, SG;
Choon Kiat Lim, Singapore, SG;
Chor Shan Cheng, Singapore, SG;
Yi Ren Hong, Singapore, SG;
Seagate Technology LLC, Scotts Valley, CA (US);
Abstract
A voice coil motor assembly in a disc drive includes first and second pole pieces held in spaced relationship to one another such that a gap is defined therebetween. A permanent magnet is located on the first pole piece within the gap and a dummy magnet is located on the second pole piece across the gap from the permanent magnet. The first and second pole pieces, together with the magnet and the dummy magnet, form a magnetic circuit conducting lines of magnetic flux within the voice coil motor and across the gap. The dummy magnet acts to encourage magnetic flux to flow across the gap in a manner such that the roll and pitch torque constants of the voice coil motor are reduced.