Neturen Co., Ltd.

Oita University

Yuji Gotoh

Kazuhiro Kawasaki

Yoshitaka Misaka

Kenta Sakurai

Noriyoshi Takaoka

An apparatus is provided to measure a depth of a hardened layer formed at a surface layer of a quenched workpiece. The apparatus includes an exciting coil configured to generate a magnetic flux to magnetize the workpiece and a detecting coil configured to detect the magnetic flux generated by the exciting coil. The exciting coil has a U-shaped excitation core portion and an excitation coil portion wound on the excitation core portion. The excitation core portion is arranged such that distal ends of magnetic poles of the excitation core portion face the workpiece. The detecting coil has a detection core portion and a detection coil wound on the detection core portion. The detection core portion is arranged between the magnetic poles of the excitation core portion and along a surface of the workpiece.

Hardened layer depth measuring apparatus

A quenching depth measuring method is used for measuring the quenching depth in a workpiece and includes the steps of: magnetizing the workpiece by disposing, in the vicinity of the workpiece, a magnetizer equipped with an exciting coil; detecting, through a detection coil, an induced magnetic field generated by the magnetization; measuring the induced magnetic field as the output voltage of the detection coil; and specifying the thickness of the quenched hardened layer of the workpiece on the basis of known electromagnetic characteristic information of an unquenched material and a fully-quenched material and an output voltage value measured by the detection coil, the unquenched material being made of the same material as the constituent material of the workpiece and being a material on which a quenching process is not performed, the fully-quenched material being a material on which the quenching process is performed.

Growing community of inventors

Oita, Japan

Yuji Gotoh