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. 10, 2017
Filed:
Jul. 20, 2016
Casio Computer Co., Ltd., Tokyo, JP;
CASIO COMPUTER CO., LTD., Tokyo, JP;
Abstract
A motor drive device includes a driver unit configured to be connected to a stepping motor, and a controller connected to the driver unit. The controller causes the driver unit to output a drive pulse to the stepping motor for causing the stepping motor to rotate stepwise in a prescribed rotation direction. The controller detects, through the driver unit, a current induced by a counter-electromotive force generated in the stepping motor in response to the drive pulse. The controller causes the driver unit to apply a counter pulse having the same electrical polarity as the drive pulse to the stepping motor so as to suppress an amount of the current induced by the counter-electromotive force when the stepping motor is not rotating in response to the drive pulse so that the amount of the induced current detectably differs between when the stepping motor is rotating and not rotating.