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. 28, 2014
Filed:
Jan. 31, 2012
Hideki Isono, Kofu, JP;
Shinji Eda, Nirasaki, JP;
Hideki Isono, Kofu, JP;
Shinji Eda, Nirasaki, JP;
Hoya Corporation, Tokyo, JP;
Abstract
A manufacturing method of a glass substrate for magnetic disk including a pair of principal surfaces is disclosed The method includes the steps of: dropping process for dropping a lump in vertically downward direction, the lump made by cutting molten glass; pressing process for forming a sheet glass material by sandwiching substantially simultaneously the lump from both sides of the dropping path of the lump with surfaces of the pair of dies at the timing when at least a cut mark of the lump protrudes from a pair of dies facing together, and performing press forming to the lump; and removing process for removing the glass material protruding from the pair of dies.