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. 26, 1993
Filed:
Jul. 16, 1991
Applicant:
Inventor:
Shinichi Nomura, Narashino, JP;
Assignee:
Seiko Seiki Kabushiki Kaisha, , JP;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
G01R / ; G01N / ;
U.S. Cl.
CPC ...
324212 ; 369 58 ;
Abstract
A magnetic disk inspection apparatus for recording and reproducing inspection signals onto and from each track on a magnetic disk, in which the inspection signals are recorded and reproduced automatically without a manual operation onto and from the magnetic disk, the maximum value is detected from the reproduction signals on the basis of the sampling signal, the average value of the maximum values is calculated for each sector, the difference between the average values in the same sector number of the adjacent tracks is determined, the change ratio based on this difference is calculated and quality of the magnetic disk is judged on the basis of this change ratio.