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:
Aug. 19, 2003
Filed:
Mar. 19, 2001
Roberto A. Collins, San Jose, CA (US);
James B. Colvin, Newark, CA (US);
Other;
Abstract
A portable induction heating system which utilizes a broadband high frequency high-power, low output impedance power generator formed from switching MOSFET devices. A voltage-controlled oscillator (VCO) or microprocessor-controlled signal generator drives a power output stage under feedback control so as to effectuate resonance at a high frequency in an induction coil assembly connected to the power generator. The power generator is operable with a switching regulator that can supply a fixed DC voltage, e.g., 12 to 48 V or a variable setpoint. The induction coil assembly includes a capacitive circuit portion connected to a conductive coil that can couple magnetic field to a susceptor. A microcontroller is provided for inputting operating parameters such as power, frequency, duty cycle and duration, and is operable to auto-tune the VCO output under feedback control by sweeping frequency at startup as well as by controlling drift during operation under a changing load.