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:
Jun. 06, 2006
Filed:
Dec. 24, 2003
Applicants:
Kenji Takayanagi, Nagaokakyo, JP;
Hideki Shirokoshi, Nagaokakyo, JP;
Inventors:
Kenji Takayanagi, Nagaokakyo, JP;
Hideki Shirokoshi, Nagaokakyo, JP;
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B 21/02 (2006.01);
U.S. Cl.
CPC ...
Abstract
A magnetic disk drive drives a switch and supplies induced power of a motor to an actuator to retract a magnetic head, if a power supply voltage is judged as being below a predetermined level. The switch is driven using an output voltage of a step-up circuit. The step-up circuit operates from before the power supply voltage drops below the predetermined level, so that the switch can be driven immediately. This makes it possible to efficiently supply the induced power to the actuator.