Patent ID: RE38714

Claim:
An electrical cord safety device, the device comprising: an electrical power cord comprising at least one current carrying conductor, insulation surrounding the current carrying conductor, and a cord outside surface; a sensor conductor for sensing temperature in the said electrical power cord, the said sensor conductor disposed in the insulation of the said electrical power cord as a continuous loop, the said sensor conductor having a positive temperature coefficient of resistivity, and further disposed between the said current carrying conductor and the said outside surface and in a manner such that continuity of the said sensor conductor is lost upon mechanical damage to the electrical power cord before the current carrying conductor is exposed, whereby the said sensor conductor further comprises a continuity detecting means; a reference conductor disposed in the vicinity of the said electrical power cord for sensing ambient temperature; and a control circuit connected to the said sensor conductor and the said reference conductor, the said control circuit comparing a first electrical quantity representative of the said sensor conductor temperature and a second electrical quantity representative of the said reference sensor temperature and interrupting current to the said current carrying conductor upon a predetermined difference between the said first electrical quantity and the said second electrical quantity.