COOLING JACKET USED FOR HIGH FREQUENCY HARDENING OF COLUMNAR WORK, AND HIGH FREQUENCY HARDENED COIL BODY USING THE JACKET

摘要

PROBLEM TO BE SOLVED: To prevent the quenching solution ejected from an upper jacket from obstructing the cooling by a lower jacket. SOLUTION: In a cooling jacket to be used for the high frequency hardening of a journal part having an upper jacket in which the quenching solution is ejected against a part upper than a center point of the journal part, and a lower jacket 513 in which the quenching solution is ejected against a part lower than the center point, a jaw part 514 projected toward the journal part and a through hole 512A to lead the quenching solution from the upper jacket received by the jaw part 514 in the direction away from the journal part, are provided above a highest ejection hole 516C in the lower jacket 513 so as not to obstruct the ejection of the quenching solution from the ejection hole.