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. 25, 1978
Filed:
Apr. 30, 1976
Applicant:
Inventor:
Ronald S Scharlack, Brookline, MA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H05B / ;
U.S. Cl.
CPC ...
219494 ; 219501 ;
Abstract
A system for controlling the temperature of the heater element of a heating apparatus by controlling the resistance of the heater element. In a preferred embodiment, the control system monitors a sensing excitation voltage at the heater element for comparison with a reference voltage, preferably at or near the zero-crossings of the heater power source cycle, and thereupon operates so that power to the heater element is always applied and terminated at zero-crossings of power cycle. In a preferred embodiment, the controller is arranged to permit only integral cycles of power to be applied to the heater element to avoid a DC bias buildup and undesirable loading of the power line.