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:
Aug. 10, 2010
Filed:
Jun. 11, 2007
Takako Hayakawa, Kanagawa, JP;
Kouki Uefune, Kanagawa, JP;
Takashi Kouno, Ibaraki, JP;
Kazuhide Ichikawa, Kanagawa, JP;
Takako Hayakawa, Kanagawa, JP;
Kouki Uefune, Kanagawa, JP;
Takashi Kouno, Ibaraki, JP;
Kazuhide Ichikawa, Kanagawa, JP;
Hitachi Global Storage Technologies Netherland B.V., Amsterdam, NL;
Abstract
Embodiments of the present invention provide a magnetic disk drive with an enclosure that prevents the low-density gas from leaking out owing to reduction of shrinkage cavities near tapped holes. According to one embodiment of the present invention, an aluminum alloy is forced into the region of the base in which the tapped hole is to be made, by squeezing in the final stage of die casting to form the base. This procedure increases the density of aluminum alloy above 2.7 g/cm, and the densified aluminum alloy in the region for tapped holes, is free of shrinkage cavities that can cause gas leakage.