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:
Nov. 22, 2016
Filed:
Nov. 07, 2014
Applicant:
Rohm Co., Ltd., Ukyo-Ku, Kyoto, JP;
Inventor:
Shigeyuki Inoue, Kyoto, JP;
Assignee:
ROHM CO., LTD., Kyoto, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02P 8/00 (2006.01); H02P 8/12 (2006.01); H02P 6/18 (2016.01);
U.S. Cl.
CPC ...
H02P 8/12 (2013.01); H02P 6/182 (2013.01); H02P 2203/09 (2013.01);
Abstract
A logic circuit controls a bridge circuit connected to a coil of a stepping motor in synchronization with an input pulse, so as to control electric power supplied to the coil of the stepping motor. A back electromotive force detector detects the back electromotive force Vacross the coil L. A load angle estimation unit estimates the load angle φ based on the back electromotive force detected in the detection period set in the high-impedance period set for the coil L. A logic circuit is configured to adjust electric power supplied to the coil such that the estimated load angle φ approaches a predetermined target angle φ.