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:
Dec. 14, 2010
Filed:
May. 28, 2008
Yoshihiko Maeda, Kanagawa, JP;
Takao Matsui, Kanagawa, JP;
Nobuhiro Kuwamura, Kanagawa, JP;
Kenichi Kuramoto, Kanagawa, JP;
Akihiro Sera, Kanagawa, JP;
Yoshihiko Maeda, Kanagawa, JP;
Takao Matsui, Kanagawa, JP;
Nobuhiro Kuwamura, Kanagawa, JP;
Kenichi Kuramoto, Kanagawa, JP;
Akihiro Sera, Kanagawa, JP;
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
Embodiments of the present invention help to detect contact between a head and a magnetic disk more accurately in specifying a heater power value for adjusting a clearance between a head element portion and the disk. According to one embodiment, a hard disk controller/multiprocessing unit (HDC/MPU) measures amplitudes of read signals in a user data field DATA. A hard disk drive (HDD) fills a gap between servo data with single data sector. The HDC/MPU measures the amplitudes of read signals in each data sector at different heater power values. It determines the heater power value at which contact occurs from the measured values.