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:
Mar. 30, 2021
Filed:
Sep. 27, 2017
Fujikin Incorporated, Osaka, JP;
Masaaki Nagase, Osaka, JP;
Kenji Aikawa, Osaka, JP;
Kaoru Hirata, Osaka, JP;
Takahiro Imai, Osaka, JP;
Tetsuo Naritomi, Osaka, JP;
Tsutomu Shinohara, Osaka, JP;
Takahiro Matsuda, Osaka, JP;
Kouji Nishino, Osaka, JP;
FUJIKIN INCORPORATED, Osaka, JP;
Abstract
A method for detecting the concentration of a specified gas contained in a mixed gas includes, in a pressure-type flow rate control device including a restriction portion, an upstream valve provided upstream of the restriction portion, and a pressure sensor for measuring the pressure between the restriction portion and the upstream valve, a step of flowing the mixed gas from the upstream side of the upstream valve in a state in which the pressure on the downstream side of the restriction portion is lower than the pressure on the upstream side of the restriction portion, a step of determining with a pressure sensor pressure drop characteristics occurring after the upstream valve is changed from an open to a closed state, and a step of determining the concentration of the specified gas in the mixed gas based on the pressure drop characteristics.