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. 17, 1992
Filed:
Jun. 27, 1991
Applicant:
Inventors:
Donald W Patrick, Midland, MI (US);
Richard A Wolcott, Midland, MI (US);
Assignee:
The Dow Chemical Company, Midland, MI (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
B01D / ; G01N / ;
U.S. Cl.
CPC ...
55 21 ; 55 67 ; 55197 ; 55386 ; 73 2336 ;
Abstract
A pressure control apparatus includes an oscillating electronic back pressure regulator connected to a pneumatic or diaphragm-operated back pressure regulator. These are connected to a separation column for effecting a predetermined program of pressure change and thereby improving quantitation of results as well as service life of the regulator.