| 摘要 |
<p>PROBLEM TO BE SOLVED: To surely execute the heating treatment even to a small work by providing a projecting part projected to the work side in the heating portion heating the faced work. SOLUTION: When the work W is hardened, firstly, a columnar work W is held with a holding means 200 so that the surface of the work W faces to the projecting part 112 of a heating conductor part 110 in a heating coil 100 and further, the projecting parts of a first and a second connecting conductor parts 120, 130. Then, the work W is rotated and the current is supplied into the heating coil 100 from a high frequency electric source to heat the surface of the work W. This heating is executed with the projecting part 112 of the heating conductor part 110 and also, executed with the projecting parts of the first and the second connecting conductor parts 120, 130. In this way, even to any portion, the work W hardened in the sufficient depth can be obtd. The projecting part 112 etc., is desirably formed so that the width of the surface faced to the work W is <=1/2 of the diameter WL of the work.</p> |
