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. 20, 1990
Filed:
Mar. 16, 1988
Applicant:
Inventors:
Tohru Namiki, Saitama, JP;
Fumio Matsui, Saitama, JP;
Kouji Shimoda, Saitama, JP;
Yosiaki Fuse, Tokyo, JP;
Assignee:
Pioneer Electronic Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ; G11B / ;
U.S. Cl.
CPC ...
369290 ; 369282 ;
Abstract
An optical information recording disk having an improved eccentricity and reduced center hole wear. A metal plate lamination hub member is inserted into and fixed in a central hole in the substrate of the disk. The metal plate lamination member is formed of a metal plate and a resin hub member having center holes dimensioned and aligned such that the center hole in the metal plate forms the center hole of the disk. The metal plate and the resin hub member are attached to one another by ultrasonic welding. The metal plate may have a hardened layer at least around its center hole.