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:
Oct. 07, 2014
Filed:
Sep. 30, 2011
Andrew Chiu, San Jose, CA (US);
Sujit Kirpekar, Fremont, CA (US);
Katalin Pentek, San Jose, CA (US);
Oscar J. Ruiz, San Jose, CA (US);
David J. Seagle, Morgan Hill, CA (US);
Andrew Chiu, San Jose, CA (US);
Sujit Kirpekar, Fremont, CA (US);
Katalin Pentek, San Jose, CA (US);
Oscar J. Ruiz, San Jose, CA (US);
David J. Seagle, Morgan Hill, CA (US);
HGST Netherlands B.V., Amsterdam, NL;
Abstract
Techniques of the present invention include detecting a touchdown between a read/write head of a disk drive and a surface of a magnetic disk using multiple touchdown sensors located at an air-bearing surface (ABS). The multiple sensors increase the likelihood that a touchdown event—i.e., a portion of the ABS of the head contacting the underlying magnetic disk surface—will be detected. During touchdown, the portion of the head contacting the magnetic disk generates frictional heat which changes a characteristic (e.g., the electrical resistance) of at least one of the sensors located at the ABS. When the sensors are connected to a detection circuit, the changing characteristic may be monitored to identify a touchdown event. The touchdown sensors may be, for example, electrically connected in either series or parallel to the detection circuit. Thus, as long as the electrical resistance of one of the sensors is changed, a touchdown event may be detected.