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. 01, 1989
Filed:
Nov. 23, 1987
International Business Machines Corporation, Armonk, NY (US);
Abstract
The method involves the steps of moving the magnetic head (8) to within aerodynamic distance from the electrically conductive surface (16) of rotating magnetic recording disk, further positioning of the head (8) until a tunnel current occurs across the gap between the head (8) and surface (16), and maintaining said tunnel current constant by using the deviations of the current from a predetermined value corresponding to a certain flying height. The apparatus comprises a tunnel electrode (9) forming an integral part of the head assembly which is attached to a distance control mechanism (5) permitting the positioning of the head assembly with a one-nanometer accuracy. The tunnel electrode (9) has a very slightly beveled shoulder (45, 47) ensuring early detection of asperities approaching the head. Gradation of the potential between tunnel electrode (9) and surface (16) of the recording disk (3) is used to enhance the response to asperities.