Abstract: Method and apparatus for inductively heating and quench hardening axially spaced cams on a steel camshaft having a longitudinally extending rotational axis concentric with a plurality of axially spaced bearings, which method and apparatus utilizes an induction heating coil having an inner surface surrounding the rotational axis of the camshaft with an insulating gap and integral quench openings for directing quenching liquid inwardly from the heating coil for the workpiece, and a high frequency power supply for selectively energizing the heating coil with a power density within the heating coil of about 20KW/in.sup.2 and an auxiliary cooling assembly fixed with respect to the heating coil and including an arrangement for spraying a cooling liquid toward the camshaft.

Abstract: A method and apparatus for heat treating camshafts includes a retractable shield positioned between a previously hardened surface and a surface being heat treated. During the induction heating and quenching cycle, a coolant is delivered to the hardened surface to maintain the temperature thereof below the tempering temperature. The shield prevents the coolant from contacting the unhardened surface and interfering with the heating and quenching thereof.

Abstract: Apparatus is provided for simultaneously rotating and axially feeding an elongated workpiece past an induction heating inductor. The apparatus includes a collet having a passageway therethrough defined in part by radially displaceable fingers normally providing an opening of a diameter smaller than the smallest diameter of the workpiece. A workpiece is pushed through the collet and the collet is simultaneously rotated for the fingers to rotate the workpiece as the latter slides axially along the fingers.