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:
Feb. 16, 1982
Filed:
Feb. 29, 1980
Applicant:
Inventor:
Theodore Wroblewski, Danvers, MA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H05B / ;
U.S. Cl.
CPC ...
219505 ; 219494 ; 219501 ; 219504 ; 338 / ; 338 23 ;
Abstract
A temperature-controlling circuit including a heating element, a portion of which is shunted by a proportional PTC thermistor having a low rate of charge of resistance with increasing temperature that controls current to the shunted and unshunted portion of the heating element to provide a proportional control of temperature. Additional embodiments are disclosed in which additional circuit elements are employed to further control current through the heating element, and in which a second thermistor connected in series with the shunted portion of the heating element accommodates wide voltage swings.