HIGH-FREQUENCY HEATING COIL FOR OSCILLATING HARDENING AND OSCILLATING HARDENING METHOD USING THE ABOVE HEATING COIL

摘要

PURPOSE:To permit simultaneous hardening to the upper face of an axial part with an approximately barrel sectional shape and to the top faces of primary and secondary projected vein parts in the approximately orthogonal direction of the axis line on the axial part of both ends of the axial part by specificly arranging coils for hardening with plural specified shapes. CONSTITUTION:This coil 100 is provided with an axial part heating coil 50 of a semiopening saddle type formed so as to correspond to the shape on the upper face of the axial part and top face heating coils 10 and 20 of a semiopening type rounded into an approximately rectangular shape so as to correspond each to the shape of the top face of projected vein parts. These three coils are connected in a series, and the coil 50 is provided with approximately parallel semicircular-arc shaped three heating conductors in the circumferential direction formed along the circumferential direction of the axial part so as to stride over the axial part and a pair of rectilineal heating conductors 52 connecting each one end and each other end in the heating conductors 51. Then, the coils 50, 10 and 20 are arranged so as to correspond to the upper face of the axial part of each work and the upper faces of the primary and secondary projected vein parts, and while the coil 100 is oscillated in the axial direction of the axial part of the work, high frequency voltage is supplied to the cutting points 51a and 51b of the central conductor 51.