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. 20, 2002
Filed:
May. 31, 2000
William Weizhong Chen, Marion, IA (US);
Brett Eugene Larson, Cedar Rapids, IA (US);
Bruce F. Lindholm, Cedar Rapids, IA (US);
Ron E. Stecker, Marion, IA (US);
Square D Company, Palatine, IL (US);
Abstract
The present invention provides a current limiting circuit breaker having a plurality of current responsive devices for opening a pair of contacts upon short circuit conditions. One such device is a conventional magnetic tripping mechanism. The other device utilizes an insulating object driven by a magnetic force caused by the short circuit current. Upon opening of the contacts with the use of the insulating object, let-through current flows through a secondary contact, positioned on the insulating object, to a positive temperature coefficient resistivity element which limits the current and arcing in the contacts. In an alternative embodiment, at least one steel component is added to increase the magnetic force, thereby providing a greater force on the insulating object. An insulation component is also added to further suppress any arc generated between the contacts when going from a closed state to an open state. In another alternative embodiment, the magnetic tripping mechanism is actuated by the device utilizing the insulating object driven by the magnetic force.