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. 19, 1997
Filed:
Jan. 13, 1995
Taturo Sasamoto, Kawasaki, JP;
Kazunori Mori, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A head positioning control system including a head for reading and writing data from and to a magnetic recording medium such as a magnetic disk of a magnetic disk drive, and an actuator for moving the head, effects head positioning control by driving the actuator on the basis of a position signal generated from the signal read out from the head. The control system compares a first velocity signal obtained by differentiating the position signal with a second velocity signal obtained by integrating a driving current fort driving the actuator, and so operates so as to correct the driving current of the actuator in a direction in which the difference of these velocity signals is offset. Preferably, the control system stores in advance the ratio of the velocity signals as correction data. Further, the control system reads out the correction data during a seek operation of the head, increases the driving current of the actuator on the basis of this correction data, and corrects the drop in torque of the actuator in the vicinity of the innermost and outermost cylinders of the magnetic disk.