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. 01, 2002
Filed:
Sep. 28, 1999
Yoshihiro Satou, Ibaraki-ken, JP;
Shinobu Yoshida, Tsuchiura, JP;
Yoshiaki Yamauchi, Ibaraki-ken, JP;
Hiroyuki Tanaka, Aichi-ken, JP;
Tomoki Hirata, Yokohama, JP;
Takashi Ishikawa, Hiratsuka, JP;
Hisahiro Miki, Chigasaki, JP;
Hisanobu Tajima, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
The number of revolutions of a disk is once increased to a higher level than a resonance frequency of a rotation support system at the startup of rotation of the disk, and subsequently servo control for a pickup actuator is made to work to read information from the disk. It is possible to increase reproducibility of the disk unbalance correction and improve the apparatus in reliability without generation of vibrations and noises, and to spin the disk at high speed.