ANNULAR WORKPIECE HEATING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a versatile heating device easily heating the whole of the surface hardened layer of an annular workpiece formed by high frequency induction heating to a tempering temperature range.SOLUTION: Provided is a heating device containing: a workpiece supporting part 30 supporting an annular workpiece W formed with a surface hardened layer Wh by induction hardening and rotating the same along the annular shape; and a heating coil 51 oppositely arranged at a part in the circumferential direction of the annular workpiece W and heating the rotating surface hardened layer Wh to a tempering temperature range. The heating coil 51 contains: the first part 51a; and a pair of the second parts 51b provided so as to mutually confront with both the edge sides of the first part 51a. The inside of the internal region 55 surrounded by the first part 51a and a pair of the second parts 51b is provided with each regulation space S in a gap with the first part 51a and in a gap with each second part 51 in a state of storing the whole shape in the radial cross section of the surface hardened layer Wh so as to arrange the annular workpieces W, and the surface hardened layer Wh is heated by feeding heating power with a commercial frequency to the first part 51a and a pair of the second parts 51b.SELECTED DRAWING: Figure 2