DEVICE FOR SCREENING OF ELECTROMAGNETIC EFFECT IN HIGH-FREQUENCY HEAT TREATMENT AND METHOD OF SCREENING Russian patent published in 2003 - IPC

FIELD: methods and devices for induction heating; applicable in various fields of mechanical engineering and designed for control of temperature of projecting parts of heated article in its high-frequency heat treatment. SUBSTANCE: device has short-circulated screening member coaxial to treated article. Screening member is made in the form of short-circuited loop consisting of two half-turns interconnected by jumpers and embracing the article not more 180 deg. In this case, one of said turns is made in plane perpendicular to article axis, and angle of inclination of the other half-turn differ from 90 deg and is selected depending on required hardness of article projecting part. Method of screening of electromagnetic effect in high-frequency heat treatment of article with projecting part consists in carrying out of continuous-consecutive heat treatment of article for different hardness for one setting including heating, hardening and tempering of projecting article surface for one pass of inductor. In so doing, in inductor passage of zone of magnetic-flux linkage with the first half-turn, temperature of heating of projecting surface is reduced to preset one due to said half-turn screening with its subsequent hardening; and in inductor entering into zone of magnetic-flux linkage with inclined half-turn, article hardened projecting part is heated and tempered. EFFECT: high-frequent heat treatment of article and tempering of its projecting part from one inductor setting. 2 cl, 3 dwg