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. 11, 1994
Filed:
Nov. 13, 1992
Applicant:
Inventors:
Yinon Barzilai, El Paso, TX (US);
William Levy, El Paso, TX (US);
Robert Sherwood, El Paso, TX (US);
Assignee:
Helen of Troy Corporation, El Paso, TX (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H05B / ; A45D / ;
U.S. Cl.
CPC ...
219225 ; 219502 ; 219499 ; 219501 ; 219241 ; 219222 ; 132229 ; 132232 ;
Abstract
A low cost heater element is disclosed which is formed of a wire wound mica paper substrate and a mica paper cover and a low cost diode acting as a negative temperature coefficient of resistance NTC temperature sensor. A control circuit provides power to the heater element in proportion to the line voltage. As a result, a light weight, low cost heater element is employed for various line voltages available throughout the world. The system employs digital logic to achieve temperature sensing, power sensing and indication that the system is on and operating at the correct temperature.