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:
Jan. 04, 1994
Filed:
Jun. 26, 1991
William F Even, Auburn, MA (US);
Digital Equipment Corporation, Maynard, MA (US);
Abstract
A data storage system having a number of disk drives is disclosed. Each disk drive is provided with a disk spindle driven by a spindle motor. The disk spindle is utilized for mounting one or more disks whose surface is used for data storage. A read/write head mounted on an actuator is provided for each disk surface. Each read/write head is positioned over a desired location on the disk surface by a control mechanism in order to transfer data to and from the disk surface. Data and position information are encoded on each disk surface according to a pre-specified format. The rotation of the disk spindle is controlled to maintain a desired angular position and velocity. A sensor signal indicative of the disk spindle angular position and velocity is obtained independently of the position information encoded on the disk surface. A reference signal, which is obtained from the disk surface, is combined with the sensor signal to adjust the angular position of the disk spindle.