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:
May. 25, 1993
Filed:
Feb. 01, 1991
Ronald R Akers, Bloomfield Hills, MI (US);
Tocco, Inc., Boaz, AL (US);
Abstract
An induction heating apparatus and method for ultra rapid annealing of a ferromagnetic strip moving at a selected velocity along a given path. The apparatus and method uses a vacuum tube R.F. oscillator having a D.C. input power supply providing D.C. voltage and D.C. current to the oscillator, a grid, a radio frequency output, and a grid feedback circuit for driving the grid. An induction heating coil surrounds the strip, and a known length along the path. A parallel capacitor bank forms the coil into a main tank circuit with a resonant frequency. Means are provided for sensing the voltage of the induction heating coil and for adjusting said D.C. voltage of the input power supply in accordance with said sensed coil voltage to maintain the power density in the strip at a selected level as the strip passes through the coil to raise the temperature of the moving strip at a rate sufficiently high to exceed the Curie point temperature of the moving strip.