Patent ID: 8723088

Claim:
A method for induction heating, the method comprising the steps of: radiating a magnetic field from a helical induction coil onto a helical rotor having a minor diameter, a major diameter and a pitch length, the helical coil having at least one loop with overlapping, adjacent ends, the loop having an inner diameter which is greater than the minor diameter of the helical rotor and smaller than the major diameter of the helical rotor; placing the helical rotor within the loop and maintaining a gap between the helical rotor and the coil; rotating the helical rotor about its longitudinal axis within an inner circumference of the induction coil at a speed of rotation; advancing the helical rotor axially through the induction coil at a speed of advance; and synchronizing the speed of advance with the speed of rotation such that the helical rotor advances one pitch length for each complete rotation.