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:
May. 22, 2001
Filed:
Jun. 24, 1998
Hiroshi Uchiike, Yamato, JP;
Kenji Ogasawara, Fujisawa, JP;
Yoshiro Amano, Yokohama, JP;
Masahiro Shimizu, Yamato, JP;
Shusuke Kurihara, Yamato, JP;
Kazunari Tsuchimto, Sagamihara, JP;
Nobuyuki Kitazaki, Chigasaki, JP;
Shinji Ueno, Fujisawa, JP;
Isao Yoneda, Yokohama, JP;
Yuji Yokoe, Yokohama, JP;
Fuminori Sai, Yokohama, JP;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A disk drive with means to prevent accidental landing of a head/slider on the disk surface is described. In one embodiment a shock sensor is provided to sense external shocks received by the mechanism. During loading (positioning) of the actuator bearing the head/slider over the disk, if a shock is sensed, loading is stopped and an immediate unloading is performed to return the actuator to the withdrawn position. In another embodiment the unload operation is performed when the rotational speed of the disk is changed. In another embodiment the unload operation is performed when the rotational speed of the disk drops below a threshold. A circuit and method for detecting when the rotational speed of the disk drops below a threshold is also provided. The unloading in the various embodiments may be performed using velocity control or without velocity control.