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, 2019
Filed:
Nov. 08, 2017
Azbil Corporation, Chiyoda-ku, JP;
Osamu Momose, Chiyoda-ku, JP;
AZBIL CORPORATION, Chiyoda-ku, JP;
Abstract
An excitation circuit includes a first switch connected between a third signal line and a first signal line supplied with a first DC voltage, a second switch connected between the third signal line and a second signal line supplied with a second DC voltage higher than the first DC voltage, third to sixth switches that reverses a polarity of a voltage on the third signal line to change a direction of an excitation current, a switching control circuit that switches the first switch at intervals shorter than intervals at which an excitation polarity is switched so that the excitation current has a first target value, and a switching control circuit that turns on the second switch when the absolute value of the excitation current is smaller than a second target value less than or equal to the first target value and that turns off the second switch when the excitation current is larger than the second target value.