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:
Sep. 23, 1980
Filed:
Sep. 25, 1978
Kenji Nakano, Yokohama, JP;
Tadahiko Nakamura, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
An automatic tracking servo control system which is adapted to control the tracking of at least one rotary signal reproducing transducer which scans successive parallel record tracks on a movable record medium. Position pulses are generated when the transducer rotates into predetermined position with respect to the record medium, and these position pulses are used in conjunction with control signals which are reproduced from the record medium and which had been recorded at spaced locations therealong in predetermined relation to the record tracks for controlling the position of the transducer with respect to the tracks scanned thereby. A detector detects the relative strength of the signal reproduced by the transducer during periodic intervals. A phase shift circuit shifts the phase of the position pulses by a selected amount during successive scanning cycles of the transducer, this amount being periodically adjusted as a function of the difference between the relative signal strengths in successive periodic intervals. The phase-shifted position pulses are used in a servo circuit, together with the control pulses, to control the tracking of the rotary head.