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:
Aug. 31, 1999
Filed:
Mar. 21, 1997
Hiroki Ohashi, Kato-gun, JP;
Fujitsu Limited, Kanagawa, JP;
Abstract
A relative-position measuring system of a recording-medium library apparatus including first to third reference flags installed for measuring the magnitude of the gradient of an accessor and a plurality of relative-position flags provided at a cell drum. A flag sensor for detecting the first to third reference flags is installed on a hand mechanism of the accessor for finding the gradients of the accessor with respect to Y and Z axes. The gradients of the accessor with respect to Y and Z axes are used for correcting design tachometer count values of the relative-position flags to give theoretical tachometer count values which are stored in a memory unit. When the accessor is moved, the relative-position flags are sensed by the flag sensor. Actual tachometer count values which are actually obtained when the relative-position flags are detected by the flag sensor are also stored in the memory unit. Then, difference data between the theoretical tachometer count values and the actual tachometer count values is calculated and stored in the memory unit as well.