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:
Aug. 02, 1988
Filed:
Jun. 29, 1987
Applicant:
Inventors:
Robert A Bredeweg, Midland, MI (US);
Jeffrey R Larson, Midland, MI (US);
Stephen W Barr, Midland, MI (US);
Assignee:
The Dow Chemical Company, Midland, MI (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01N / ;
U.S. Cl.
CPC ...
73 231 ;
Abstract
A flow programmer for gas chromatography of the type having a mass flow meter for controlling the flow rate of a gas chromatography carrier gas controllable at a selected carrier gas flow rate program by an electrical input to the mass flow meter and an electrical circuit for generating the electrical input. The improvement is that the electrical circuit for generating the electrical input is an analog electrical circuit which includes an operational amplifier having an electrical capacitor in the feedback loop of the operational amplifier to produce a selected voltage input program.