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. 13, 2018
Filed:
Dec. 21, 2016
Hitachi Metals, Ltd., Minato-ku, Tokyo, JP;
Ryan Johnson, Fort Collins, CO (US);
Alexei V. Smirnov, Fort Collins, CO (US);
Patrick Albright, Wellington, CO (US);
Cy Jordan, Fort Collins, CO (US);
Arun Nagarajan, San Bruno, CA (US);
Hitachi Metals, Ltd., Tokyo, JP;
Abstract
Gas insensitive systems and methods for controlling the mass flow rate of a gas through a primary conduit are disclosed. The method includes producing, in a secondary conduit, an assessment flow that has a changing pressure; calculating a first measure of a flow rate of the assessment flow based upon a rate-of-change of the pressure of the assessment flow; and measuring the assessment flow with a mass flow meter that is affected by the composition of the gas to produce a second measure of the assessment flow. An adjustment signal is generated based upon a difference between the first measure and the second measure, and a gas-corrected flow signal is generated by adjusting a measured-flow signal of a mass flow controller with the adjustment signal. The gas-corrected flow signal is used by the mass flow controller to control a flow rate of the gas through the primary conduit.