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. 22, 1991
Filed:
Apr. 10, 1989
Ryuichi Matsuzaki, Narashino, JP;
Seiko Seiki Kabushiki Kaisha, , JP;
Abstract
Hard disk testing apparatus and method having a plurality of heads mounted on a carriage capable of moving in the direction of a hard disc at intervals defined by dividing the radius of the hard disc, write circuit for writing a test signal through the heads in the hard disc, read circuit for reading a signal written through the heads, and measuring function for measuring a separation between one head of the heads and another head of the heads provided adjacent to the one head based on a shift distance of the another head shifted to read a signal written by the one head. A separation of the heads is accurately measured without a measuring device, and micro adjustment of positions of the heads based on the measured separation is not required. The possibility of double testing of or failure in testing tracks on the border is eliminated, and thereby disc test is efficiently performed.