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:
Apr. 25, 2006
Filed:
Oct. 28, 2004
Kiyoshi Sasaki, Tokyo, JP;
Kiyoshi Sasaki, Tokyo, JP;
Calsonic Kansei Corporation, Tokyo, JP;
Abstract
An output port open control device () allows a port (P) which outputs PWM signals of a Cos+ side to be in a high impedance state in a period in which respective PWM signals of Cos+ and Cos− supplied to a S-phase coil () of a stepping motor () are in a ground level, induced voltage corresponding to a magnetic flux variation caused in accordance with rotation of a magnet rotor () is generated in the S-phase coil (), a voltage comparator () compares the induced voltage with a previously set threshold value and outputs presence or absence of the induced voltage, and a zero-reset judging device () determines that a pointer () is in the middle of rotation when the induced voltage is detected, and determines that the pointer () is in contact with a stopper mechanism () when it is not detected.