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:
Dec. 09, 1997
Filed:
Apr. 17, 1996
Kazushi Tsuwako, Machida, JP;
Fujio Harako, Fujisawa, JP;
Katsumi Suda, Sagamihara, JP;
Michio Nakajima, Sagamihara, JP;
Isao Yoneda, Yokohama, JP;
Kenji Ogasawara, Fujisawa, JP;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A disk drive apparatus and read error recovery method in a disk drive apparatus removes thermal asperities on disk surfaces. A projection, such as a thermal asperity, on the recording surfaces of disks is detected when a signal transducer contacts the projection. The flying height of the signal transducer is lowered, e.g., by reducing the disk rotation speed from the normal rotation speed in read/write operations, while the signal transducer is positioned over the detected projection on the track. The signal transducer strikes the projection to break the projection. This avoids a subsequent error from being caused by the thermal asperity.