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. 08, 2002
Filed:
Nov. 02, 2000
Applicant:
Inventor:
Sadatoshi Narazaki, Chiba, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02P 8/00 ;
U.S. Cl.
CPC ...
H02P 8/00 ;
Abstract
A device is provided for chopping a control signal of an initial excitation phase or a final excitation phase by a predetermined cycle during low speed rotation control of an excitation phase control signal (excitation control signal) of a stepping motor when acceleration control and deceleration control of the stepping motor are effected, thereby reducing an excessively great driving current created during low speed rotation of the stepping motor, particularly the initial retaining excitation period during acceleration control and the final retaining excitation period during deceleration.