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:
Oct. 30, 2012
Filed:
Sep. 11, 2009
Masayuki Kurita, Kanagawa, JP;
Kenji Kuroki, Kanagawa, JP;
Kenichi Kuramoto, Kanagawa, JP;
Yoshihiko Maeda, Kanagawa, JP;
Masayuki Kurita, Kanagawa, JP;
Kenji Kuroki, Kanagawa, JP;
Kenichi Kuramoto, Kanagawa, JP;
Yoshihiko Maeda, Kanagawa, JP;
Hitachi Global Storage Technologies, Netherlands B.V., Amsterdam, NL;
Abstract
A method for measuring change of clearance between a head and a disk. The method includes reading a preliminarily written data string for clearance measurement on a disk to obtain a first measured value corresponding to a clearance, and writing a new data string for deterioration check onto the disk and reading the data string for deterioration check to obtain a second measured value corresponding to the clearance. The method also includes determining a deterioration of the data string for clearance measurement from a difference between the first measured value and the second measured value, measuring a clearance change using the data string for clearance measurement by a normal operation if the determination is that the data string for clearance measurement has not deteriorated, and measuring a clearance change by an operation different from the normal operation if the determination is that the data string for clearance measurement has deteriorated.