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:
Apr. 15, 1997
Filed:
Apr. 05, 1996
Alireza Rahimi, Los Altos, CA (US);
Kamran Oveyssi, Aptos, CA (US);
Seagate Technology, Inc., Scotts Valley, CA (US);
Abstract
A head-arm assembly having a pair of trapezoidal-like shaped coil bobbins for improved torque and moments of inertia in a voice coil motor (VCM) for a disk drive. The VCM includes a magnetic structure that employs three magnet polarity zones having two flux transition zones. The magnetic structure is able to employ relatively thin pole pieces without saturation or leakage. The thin pole pieces permit use of a thicker magnet in the same envelope size. The result is an increased flux density in the air gap of the VCM, giving higher torque and shorter access time. In addition to improving the torque and moments of inertia, the present invention allows use of thicker magnets (thinner pole pieces) and allows the option of using a thinner coil that is wider radially. In another version, an oval-shaped coil may be used for increased effective length when disposed within a magnetic field of a VCM.