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:
Feb. 08, 2022
Filed:
Aug. 28, 2020
Applicant:
Hoya Corporation, Tokyo, JP;
Inventors:
Masao Takano, Akishima, JP;
Shinji Eda, Hung Yen Province, VN;
Assignee:
HOYA CORPORATION, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 17/02 (2006.01); G11B 17/038 (2006.01);
U.S. Cl.
CPC ...
G11B 17/021 (2013.01); G11B 17/038 (2013.01);
Abstract
In order to suppress the occurrence of adhesion between magnetic disks and spacers when the magnetic disks and the spacers are removed from a hard disk drive apparatus in which the magnetic disks and the spacers are installed, a surface roughness Ra of a main surface of a ring-shaped glass spacer to be arranged in contact with a magnetic disk is set to be not larger than 1.0 μm, and an average inclination RΔa of the main surface is set to be at least 0.02.