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. 19, 1993
Filed:
Oct. 07, 1991
Naoyuki Kagami, Fujisawa, JP;
Hiroaki Kubo, Atsugi, JP;
Keiichi Okada, Kanagawa, JP;
Makoto Takekoshi, Yokohama, JP;
International Business Machines Corporation, Armonk, NY (US);
Abstract
In this invention, a driving circuit for moving a head in the radial direction on the recording surface of a disk is coupled to a velocity detecting circuit for detecting the velocity at which the head moves. A velocity profile is provided for storing information on the target velocity of the head. A driving signal generating circuit is coupled to the velocity profile and the velocity detecting circuit for comparing a signal from the velocity detecting circuit with a signal from the velocity profile. The driving signal generating circuit outputs a driving signal to the driving circuit based on the result of the comparison. A controller is coupled to the driving circuit for measuring a time required for moving the head a predetermined distance at a predetermined reference value, and modifying the driving signal based on the result of the comparison. Scatter in feedback quantities or fluctuation in the driving signal during velocity control is thereby corrected.