Induction hardening system and method

A method of induction heat treating a gear, wherein the gear includes an inner surface, a plurality of splines and a plurality of webs, wherein the plurality of splines and the plurality of webs are located along the inner surface, and wherein the plurality of splines are induction heat treated and the plurality of webs remain untreated by induction heating, and wherein each of the plurality of spline groups have a first width and each of the plurality of webs have a second width, the method comprising:

• placing the gear within a workstation, wherein the workstation has a power source and an inductor coil, and wherein the inner surface of the gear is positioned to be proximate to the inductor coil, wherein the power source provides alternating current to the inductor coil, and wherein the inductor coil includes at least one heating loop and at least one non-heating loop, where the heating loop has a heating loop width and the non-heating loop has a non-heating loop width, and wherein the non-heating loop width is configured to be about equal to the second width of the gear, and wherein the heating loop width is configured to be about equal to the first width of the gear;
• rotating the gear about an axis of rotation, wherein the gear is rotated relative to the inductor coil;
• energizing the inductor coil to a predetermined frequency to create an alternating magnetic field, wherein the magnetic field developed in the heating loop induces an eddy current in the plurality of splines of the gear, and wherein a net alternating current that is about zero is created in a portion of the non-heating loop;
• and
• maintaining the inductor coil at the predetermined frequency for a predetermined amount of time to induction harden the gear at the plurality of splines;
• and
• quenching the gear by fluid, wherein fluid is supplied to the gear by a quenching plate having a series of fluid passageways, and wherein a flux intensifier is included within the quenching plate, and wherein the inductor coil is positioned within the workstation by the quenching plate and a portion of the inductor coil is located within the quenching plate.