HARDENING APPARATUS, AND HARDENING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a hardening apparatus that reduces a hardening distortion difference between an upper stage and a lower stage when an object article vertically stacked is submerged in a cooling tank and cooled, and to provide a hardening method that suppresses dispersion of hardness and deformation degrees.SOLUTION: A hardening apparatus 1 includes a cooling tank 3 containing an oil 2 and a circulation device 6 that is equipped with discharge ports 5A, 5B at the bottom of the cooling tank 3 and circulates the oil 2 in the cooling tank 3. The cooling tank 3 includes object article housing means 7 that houses an object article W and a distributor plate 20 that is arranged around the object article housing means 7 and controls a flow of the oil 2. An upper side clearance 30A between the object article housing means 7 and the distributor plate 20 is narrower than a lower side clearance 30B.SELECTED DRAWING: Figure 2