Neturen Co., Ltd.

Oita University

Keio University

Nihon Parkerizing Co., Ltd.

Yoshitaka Misaka

Yoshimasa Tanaka

Kazuhiro Kawasaki

Tatsuya Ishii

Kenji Koyanagi

Tsutomu Ito

Yasuharu Ogawa

Hitoshi Nakatsu

Masato Yoshioka

Masaki Sagae

Yuji Asano

Kengo Fukazawa

Yuji Gotoh

Fumiaki Ikuta

Arata Suda

Masaaki Beppu

Akira Terajima

Kenta Sakurai

Yasuyuki Koyata

Noriyoshi Takaoka

Yoshihiro Ikeda

Jun Komotori

Shumpei Ota

An induction heating device is provided. The induction heating device comprises a plurality of induction heating devices disposed at intervals along the circumference of a ring-shaped workpiece, a setting unit for setting induction heating conditions, and a switching control unit. Each of the plurality of induction heating devices comprises heating coils disposed facing areas to be heated of the workpiece, a plurality of transformers connected to the heating coils in parallel, a plurality of matching units connected to any one of the plurality of transformers, an inverter unit having a rectifier unit and an inverter unit, an inverter control unit having a rectification control unit, and a group of switches.

Induction heating device, induction heating equipment, induction heating method, and heat treatment method

An induction heating device and an induction heating method are provided. The entire areas to be heated of the workpiece can be uniformly heated to a predetermined high temperature, and uniform heating is possible even when the workpiece deforms in a non-uniform manner during heating. When areas to be heated are established on a workpiece so as to extend in one direction and the areas to be heated are induction-heated, the deformation amount on one edge of the areas to be heated is different from that on the other. This induction heating device includes; heating coils facing a portion of the areas to be heated when the workpiece is induction-heated; and a relative transfer means for transferring the workpiece and the heating coils along one direction in a relative manner, and the heating coils are disposed so as to correspond to the areas to be heated during the heating period.

According to an embodiment, an induction heating coil includes a heating conductor portion which is formed of a conductor member and has a zigzag shape in which a bent portion opened to one side in a first direction and a bent portion opened to the other side in the first direction are alternately continuously arranged in opposite directions along a second direction crossing the first direction.

Induction hardening apparatus, induction hardening method, induction heating coil, heat treatment apparatus, and heat treatment method

An object of the present invention is to provide, as a simple method, a surface nitriding treatment method of a titanium material, forming a hardened nitrided layer excellent in abrasion resistance on the surface of a titanium material in a shorter time. In order to achieve the object, the present invention adopts a surface nitriding treatment method of a titanium material, wherein a hardened nitrided layer is formed on the surface of the titanium material, by blowing nitrogen gas at a flow rate of 10 L/min or more to the surface of the titanium material while the titanium material is being heated to 800&#xb0; C. to 1000&#xb0; C. in an inert gas atmosphere.

Surface nitriding treatment method of titanium material

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

Object of the present invention is to provide a welding method prevented the fracture at the spot welding zone by recovering the strength of a spot welding zone, namely, the ductility and the toughness in the spot welding zone, and a weld structure manufactured by the method. In the welding method, a spot welding zone provided with a weld nuggetis formed by conducting spot welding on the heat treated steel sheets in a stack; the spot welding zone is tempering treated by the high-frequency electrical current application to make the weld nugget have a hardness of 150% or less of the hardness of the heat treated steel sheets, and the heat affected zone surrounding the weld nugget is made to have a hardness of 30% to 90% of the hardness at the weld nugget before the tempering treatment by the high-frequency electrical current application.

Welding method and weld structure

An induction heating device and an induction heating method are provided. The entire areas to be heated of the workpiece can be uniformly heated to a predetermined high temperature, and uniform heating is possible even when the workpiece deforms in a non-uniform manner during heating. When areas to be heated are established on a workpiece so as to extend in one direction and the areas to be heated are induction-heated, the deformation amount on one edge of the areas to be heated is different from that on the other. This induction heating device includes: heating coils facing a portion of the areas to be heated when the workpiece is induction-heated; and a relative transfer means for transferring the workpiece and the heating coils along one direction in a relative manner, and the heating coils are disposed so as to correspond to the areas to be heated during the heating period.

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.

Quenching depth measurement method and quenching depth measurement apparatus

Providing an iron and steel material having quenched surface part, avoiding oxidation of a compound layer formed on the surface of the iron and steel material due to quenching, its production method, and an induction-quenched component. A quenched iron and steel materialcomprises an iron and steel material, a compound layerformed on the iron and steel material, and an antioxidant cover layerformed on the compound layer. The iron and steel materialhas a hardened layer having a given depth, and the surface of the iron and steel materialhas enhanced hardness. A method for producing the iron and steel materialcomprises a first step for forming the antioxidant cover layerto cover the compound layerformed on the iron and steel material, and a second step for applying induction hardening to the iron and steel materialhaving the compound layerand the antioxidant cover layer, with the temperature increased in a given heating time until the given heating temperature is reached, and with cooling immediately performed once the heating temperature is reached.

Growing community of inventors

Tokyo, Japan

Yoshitaka Misaka