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:
Jan. 01, 2013
Filed:
Mar. 30, 2010
Xiaosheng Guan, Beijing, CN;
Xiaosheng Guan, Beijing, CN;
Agilent Technologies, Inc., Santa Clara, CA (US);
Abstract
A device for providing a constant mass flow rate to a downstream column system of a gas chromatograph includes a small full scale mass flow controller that controls carrier gas to flow at a first mass flow rate and a flow resistance element, including an inlet port connected to a sample inlet, an outlet port connected to the downstream column system, and a pressure sensing port in fluid communication with the outlet port and the mass flow controller. A sample inlet pressure controller controls the sample inlet at a first pressure, and a pressure sensor measures a second pressure of the carrier gas at the pressure sensing port. A set point of the first pressure is determined as a function of the second pressure, flow resistance of the flow resistance element, and a second mass flow rate from the inlet port to the outlet port of the flow resistance element.