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:
Jan. 12, 1999
Filed:
Apr. 30, 1997
Roy Lynn Wood, Yukon, OK (US);
Steven S Eckerd, Oklahoma City, OK (US);
Seagate Technology, Inc., Scotts Valley, CA (US);
Abstract
Apparatus and method for measuring the maximum static friction force and the kinetic friction force between the heads of a disc drive and discs adjacent the heads. The disc drive is rotated by a computer controlled spin-up motor which provides constant angular acceleration of the disc drive. Voltages at the ends of the windings of a spindle motor of the disc drive are sampled to detect the angular acceleration at which disc rotation relative to the heads begins, from which the static friction force and the kinetic friction force are determined. The angular acceleration of the disc drive is monitored through the sampling of velocity commands used to control the angular acceleration of the disc drive, or through the use of an accelerometer mounted with respect to the disc drive.