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. 22, 2009
Filed:
Jul. 27, 2007
Sumie Takeda, Kanagawa, JP;
Katsumoto Onoyama, Kanagawa, JP;
Iwao Oshimi, Kanagawa, JP;
Hiroyuki Oosawa, Kanagawa, JP;
Sumie Takeda, Kanagawa, JP;
Katsumoto Onoyama, Kanagawa, JP;
Iwao Oshimi, Kanagawa, JP;
Hiroyuki Oosawa, Kanagawa, JP;
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
Embodiments of the present invention prevent occurrence of a write pole erasure in the event of a power failure within a magnetic disk apparatus of a perpendicular magnetic recording system. According to one embodiment of the present invention, a recording current is flowed through a magnetic head to record data in a magnetic disk. An occurrence of a power failure in the magnetic disk apparatus is detected. When a power failure has occurred, the recording head is demagnetized with power in case of a power failure. The recording head is unloaded after the recording head has been demagnetized. For the power in case of a power failure, back electromotive force of a spindle motor can be utilized. As a result, effects exerted on data recorded in the magnetic disk due to residual magnetism remaining in the recording head can be eliminated.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile