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:
Oct. 12, 1999
Filed:
Jun. 18, 1997
Applicant:
Inventors:
Mark A Flood, Mayfield Heights, OH (US);
William B Cook, Northfield, OH (US);
Mark E Taylor, Chesterland, OH (US);
Steven P Richter, South Euclid, OH (US);
Assignee:
Allen-Bradley Company, Inc., Milwaukee, WI (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G05B / ;
U.S. Cl.
CPC ...
364131 ; 364133 ; 364187 ;
Abstract
A redundant industrial controller system has a primary controller backed up by a secondary controller and recovers from a power loss by analyzing the state memories of the controllers to reach a determination of which controller would best be suited to assume primary control status without resorting to arbitrary tie-breaking procedures or race conditions. The rules and their inputs are applied by both controllers which independently make the determination as to which controller should be the primary controller.