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:
Feb. 11, 2003
Filed:
Mar. 31, 2000
Yoji Saito, Tokyo, JP;
Yokogawa Electric Corporation, Tokyo, JP;
Abstract
A valve positioner and current-to-pneumatic converter having a reduced number of components and increased current allocation to a current-to-pneumatic conversion module therein, wherein current signals containing set point information are applied to a digital computation circuit through input terminals which carries out control computation to control valve openings so that each valve opening agrees with each corresponding set point; and a current-to-pneumatic conversion module converts the control outputs from the digital computation circuit into pneumatic signals; and further comprising a power voltage generator that generates an internal power voltage from the current signal; a variable impedance circuit connected in series to the power voltage generator and in parallel to the current-to-pneumatic conversion module; and an impedance control circuit that controls the impedance of the variable impedance circuit.