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. 23, 1979
Filed:
Jul. 06, 1977
David M Chick, Aldershot, GB;
David B Hawthorne, Windlesham, GB;
Data Recording Instrument Co. Ltd., Staines, GB;
Abstract
In a magnetic-disc data storage device using exchangeable discs for the recording of data on circular tracks, a reference track is provided on the disc and during interruptions in the transfer of data, a read-write head is moved to the reference track and the error in its expected position, due to dimensional changes in the disc or the storage device or due to misalignment of the head, is measured. In subsequent data tracks access the position of the head is corrected by error measured so that the head is correctly aligned with the selected data track. Measurement of the error is carried out more frequently when the error is changing rapidly.