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:
Feb. 24, 1998
Filed:
Jul. 16, 1996
Norihisa Yanagihara, Ibaraki-ken, JP;
Shinsuke Nakagawa, Ibaraki-ken, JP;
Shigeyuki Kobata, Odawara, JP;
Masao Iwakura, Odawara, JP;
Kazuo Sakai, Ibaraki-ken, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A load torque imposed on a take-up reel motor is estimated from the current in a take-up reel motor and the rotational speed of the take-up reel. The current value supplied to the take-up reel motor is adjusted on the basis of the estimated load torque. A tape feed rate detected is compared with a reference signal produced from a target tape speed signal. On the basis of the comparison result, the torque of the take-up reel motor is controlled in such a manner that the tape feed rate assumes a predetermined value. The gain of a speed control system for controlling the rotational speed of the take-up reel is adjusted on the basis of a detected period of tape speed.