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. 25, 2002
Filed:
May. 04, 2000
Applicant:
Inventor:
Kai Meng Hock, Singapore, SG;
Assignee:
Sony Precision Engineering Center (Singapore) PTE Ltd., Singapore, SG;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 1/722 ;
U.S. Cl.
CPC ...
G11B 1/722 ;
Abstract
A motor constant K of a sled mechanism of an optical disc drive is to be measured. To this end, a parameter measurement device for the sled mechanism includes an oscilloscope for detecting the back-electromotive force E of a sled motor a laser Doppler meter for detecting the movement velocity v of the pickup and a computer The computer calculates an equation E =K R v , where R is the resistance of a motor, to find the motor constant K .