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. 12, 2011
Filed:
Sep. 07, 2007
Akihiko Aoyagi, Kanagawa, JP;
Kazuhide Ichikawa, Kanagawa, JP;
Takashi Kouno, Ibaraki, JP;
Hitoshi Shindo, San Jose, JP;
Akihiko Aoyagi, Kanagawa, JP;
Kazuhide Ichikawa, Kanagawa, JP;
Takashi Kouno, Ibaraki, JP;
Hitoshi Shindo, San Jose, JP;
Hitachi Global Storage Technologies, Netherlands B.V., Amsterdam, NL;
Abstract
Embodiments of the present invention provide a magnetic disk drive that can estimate the amount of gas filled in a housing precisely and simply. According to one embodiment, a magnetic disk drive including a housing in which a magnetic disk and a magnetic head are accommodated and gas having lower density than air is filled, a heating body provided in the housing, and means for holding a reference value of a parameter representing the temperature change speed of the heating body when the heating body is heated in the housing filled with a predetermined reference amount of the gas.