| 摘要 |
<p>1,129,490. Induction heating. AEG-ELOTHERM G.m.b.H. 26 Sept., 1967 [14 Oct., 1966], No. 43830/67. Heading H5H. [Also in Division C7] A process for the uniform inductive heating of metal workpieces which have continuously changing radii of curvature in the peripheral direction, e.g. cams or cam-shafts, so as to provide a uniform surface-temperature distribution, comprises reducing the frequency of the heating current when the surface with a relatively small radius of curvature has attained approximately the Curie point. An increase of the specific power in the workpiece is carried out simultaneously. The frequency reduction is carried out by using two separately driven generators, the outputs of which are optionally connectible to energy consuming heat conductors and/or heat transmitters, or by using a generator with a polarity reversing driving motor, which is switched to a lower speed of rotation, or by introducing resistances into the rotor-circuit of the drive motor of a single-phase generator, or by using a converter with controllable valves or semi-conductors.</p> |
