| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the spring-out of a silicon steel sheet by interposing an insulating block between the laminated silicon steel sheet provided on the way of an induction coil and a cooling jacket. SOLUTION: The surface layer of a work W is made into austenitic structure by heating the induction coil 2 in a semi-circle opening induction hardening apparatus 1 and made into martensite by injecting water from a water-cooling jacket 3 and cooling the work. The insulating blocks 8, 9 are interposed between the U-shaped silicon steel sheets 6, 7 fitted to the longitudinal parts 4, 5 of the induction coil 2 and the water-cooled jacket 3. Concretely, this insulating blocks 8, 9 are made of an easy-to-obtain heat resistant insulating material such as a glass epoxy, without using adhesive. Since the adhesive is burnt and carburized, it can not be used. In such a way, the spring-out of the silicon steel sheets 6, 7 is surely prevented and the hardening of the work W for long time can be applied and the productivity is improved and also, the cast of maintenance and checking of the equipment can be reduced.</p> |
