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:
Apr. 01, 1997
Filed:
Jun. 01, 1994
James A Bauer, Asheville, NC (US);
Nelson R Palmer, Arden, NC (US);
Kathryn M Palmer, Monroeville, PA (US);
Henry A Wehrli, III, Monroeville, PA (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
A circuit controller for selectively connecting a power source to a load includes a switching mechanism, which selectively connects the power source to the load and switches a current which flows through the switching mechanism, and a substantially radiant energy dissipating positive temperature coefficient current limiter for limiting the current which flows through the switching mechanism. The switching mechanism includes a current sensor, which senses the current flowing through the switching mechanism and provides a sensed current value, and a switching controller for disconnecting the power source from the load whenever the sensed current value is above a predetermined current value. The switching mechanism may include a contactor having separable contacts which are responsive to the switching controller. The current limiter may have a first resistance which results from a first series current, and a higher second resistance which results from a second series current. The ratio of the second resistance to the first resistance may exceed 16. The current limiter may be a tungsten or, alternatively, a carbon conductor. The tungsten conductor dissipates greater than 70 percent of the energy of the short circuit current by radiation. The current limiter may further include a tubular glass cylinder which encloses the conductor therein. The cylinder may have two copper ends, each of which are electrically connected to a corresponding end of the conductor within the cylinder. The cylinder may further enclose a non-oxidizing gas, such as nitrogen, helium, argon, krypton or a halogen gas mixture. The conductor may be wound on a ceramic cylinder within the cylinder.