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:
Dec. 25, 1990
Filed:
Feb. 14, 1989
Fumio Tajima, Juo, JP;
Hiroshi Katayama, Hitachi, JP;
Tunehiro Endo, Hitachioota, JP;
Kunio Miyashita, Hitachi, JP;
Seiichi Narushima, Naka, JP;
Jun Ohya, Katsuta, JP;
Kouchi Saito, Kitaibaraki, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A speed control apparatus is provided for controlling a speed of a movable equipment in such a way that the speed of the movable equipment is detected, calculates a deviation value between a detected speed of the movable equipment and a speed instruction signal, and controls the speed of the movable equipment based on the deviation value. The speed control equipment detects harmonic wave components included in the detected speed and reduces the harmonic wave components from the speed instruction signal so as to control the speed of the movable equipment.