Abstract: An induction apparatus including a hardening control unit for controlling an induction hardening apparatus based on setup conditions data; a hardening monitoring unit that measures, as measurement data, the electric quantity in an electric circuit and that monitors an induction hardening status; and a data collecting unit that collects the data from various sensors in the induction hardening apparatus obtained when the induction hardening apparatus subjects the work to an induction hardening based on the setup conditions data outputted from the hardening control unit and that collects the measurement data from the hardening monitoring unit to store the collected data from the various sensors and the measurement data so that the collected data are associated to each other.

Abstract: 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.

Abstract: A composite member includes a metal shaft member, and a fit member having an insertion hole and secured onto the shaft member inserted in the insertion hole. The shaft member includes a receiving portion contacting a first end surface of the fit member, a first radially enlarged portion adjacent to the receiving portion in an axial direction and tightly contacting an inner peripheral surface of the insertion hole, and a second radially enlarged portion adjacent to the first radially enlarged portion in the axial direction and tightly contacting a second end surface of the fit member opposite to the first end surface. The first and second radially enlarged portions are formed by applying a compressive load in the axial direction to the shaft member and an alternating load in a direction intersecting the axial direction to a portion of the shaft member inserted in the insertion hole.

Abstract: A method for manufacturing a rack bar includes joining axial end portions of first and second bar members to each other, and forming a power transmission section on the second bar member. The first bar member has a toothed portion. When the second bar member is hollow, the method may further include thickening a wall of a portion of the second bar member along the axial direction so as to be coaxial with the first bar member. When the second bar member has a greater diameter than the first bar member, the method may further include cutting an outside diameter of a portion of the second bar member in the axial direction so as to be coaxial with the first bar member. The power transmission section is formed on the portion of the second bar member where the wall has been thickened and/or the outside diameter has been cut.

Abstract: A rack bar includes a shaft portion and a rack toothed portion provided on the shaft portion. The rack toothed portion includes a plurality of rack teeth provided side by side in an axial direction of the shaft portion to mesh with a pinion gear. Each of the rack teeth includes a tooth tip portion, a contact face arranged obliquely relative to the axial direction and configured to contact the pinion gear, and a rounded corner portion between the tooth tip portion and the contact face. A first radius defining a central area of the rounded corner portion with respect to a tooth width direction is larger than a second radius defining another area of the rounded corner portion other than the central area.

Abstract: 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.

Abstract: Provided is spring steel for suspension suppressing or not requiring addition of expensive alloy elements, having a large tensile strength, and excellent in cold formability and delay fracture resistance, wherein at a cross-section parallel to a rolling direction, 90% or more of the metal microstructures by area fraction is tempered martensite, and at a cross-section parallel to the rolling direction, in a range of 10% of diameter or thickness from the surface, a ratio of a length in a long axis direction of prior austenite grains and a length in a direction perpendicular to the long axis direction of the prior austenite grains is 1.5 or more and a ratio of <011> fraction/<111> fraction of martensite texture as seen from the rolling direction is 3.0 or more.

Abstract: A power conversion apparatus and a power conversion method are provided for heat treatment. The power conversion apparatus includes a rectifier configured to convert AC power to DC power, a smoothing filter configured to control the DC power received from the rectifier to be constant, an inverter configured to covert the DC power received from the smoothing filer into high-frequency power by turning the DC power on and off using a switching device made of an SiC semiconductor, and a control unit configured to control the rectifier and the inverter. A rating of output power output from the inverter is determined in accordance with a frequency of the high-frequency power output from the inverter, a current-applying time, and an operation rate obtained by dividing the current-applying time by a sum of the current-applying time and a non-current-applying time.

Abstract: 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° C. to 1000° C. in an inert gas atmosphere.

Abstract: A method of manufacturing a lead wire for a solar cell includes heating a wire material by a direct resistance heating or by an induction heating to reduce a 0.2% proof stress of the wire material while conveying the wire material and plating the wire material that is in a heated condition obtained by the direct resistance heating or by the induction heating while further conveying the wire material. An apparatus is configured to implement the method, and includes a plating bath, a conveyor mechanism configured to convey the wire material, a heater configured to heat the wire material, and a controller configured to control the conveyor mechanism and the heater.

Abstract: A direct resistance heating simulation method is provided. In this method, a welding region and its peripheral region of steel sheets to be welded by a pair of electrodes are divided into a plurality of elements. A coupled analysis is performed such that a temperature, a metal structure, stress and strain at each element are determine in a mutually associated manner based on Joule loss obtained through a current analysis and a magnetic field analysis for each element. The coupled analysis is repeated to predict an effect of one or more parameters, including at least one of a frequency, a magnitude and an application time of electric current to be applied to the electrodes, a cooling time, a pressure applied from the electrodes to the steel sheets and a shape of the electrodes, on welding quality after a post-heating by direct resistance heating and to improve weld strength.

Abstract: A power supply apparatus for induction heating is provided. The power supply apparatus includes a smoothing filter configured to smooth a pulsating current of DC power output from a DC power supply, and an inverter configured to convert the DC power that has been smoothed by the smoothing filter into AC power. The smoothing filter includes a plurality of capacitors having different internal inductances and connected to each other in parallel between input terminals of the inverter, each of the capacitors being connected to the input terminals of the inverter directly or through a pair of bus bars. The plurality of capacitors includes a first capacitor and a second capacitor, the first capacitor having smaller internal inductance than the second capacitor and a shorter conductive path between the input terminals of the inverter than the second capacitor.

Abstract: A heating apparatus, a heat treatment apparatus, and a heating method are provided. The heating apparatus includes a workpiece support on which a ring-shaped workpiece is placed, a rotary drive assembly, and a heater configured to heat the workpiece. The workpiece support includes a plurality of rotating rollers arranged in a circumferential direction. The rotary drive assembly is configured to rotate the plurality of rotating rollers to rotate the workpiece placed on the workpiece support along a ring shape of the workpiece. The heater includes a heating coil configured to induction-heat the workpiece on the workpiece support at a heating position, and an actuator configured to move the heating coil at the heating position relative to the workpiece to adjust a distance between the workpiece and the heating coil.

Abstract: A hollow rack bar and a method of manufacturing the hollow rack bar are provided. The hollow rack bar includes a hollow blank pipe portion having a uniform wall thickness, and a rack toothed portion. The rack toothed portion includes teeth, a flat portion having a flat surface and arranged side by side with the teeth in a direction along a center axis of the blank pipe portion, and a slanted portion provided at an end of the flat portion with respect to a direction perpendicular to the center axis and arranged to be lower than the flat portion. A length of the slanted portion projected on a straight line perpendicular to the center axis and parallel to the surface of the flat portion is longer than zero and equal to or shorter than the wall thickness of the blank pipe portion.

Abstract: A method and an apparatus for manufacturing a stepped member are provided. An intermediate portion of a shaft workpiece is radially enlarged while being compressed in an axial direction by applying alternating load to the intermediate portion in a direction intersecting the axial direction in a state in which pressure that compresses the shaft workpiece in the axial direction is applied to both ends of the shaft workpiece. The enlarged intermediate portion of the shaft workpiece is cat in a direction perpendicular to the axial direction so that the shaft workpiece is divided into two stepped members. Each of the stepped members has a shaft portion and a head portion provided at an axial end of the shaft portion, and the head portion has a larger diameter than the shaft portion.

Abstract: A current applying apparatus includes a pair of electrodes configured to contact a workpiece to apply an electric current to the workpiece, and a bus bar arranged to extend along the workpiece. At least one of the electrodes includes a moving electrode configured to move relative to the bus bar and the workpiece such that an electric current flows between the bus bar and the workpiece through the moving electrode, the moving electrode being connected to the bus bar so as to be movable relative to the bus bar, and the moving electrode being configured to contact the workpiece so as to be movable relative to the workpiece.

Abstract: 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.

Abstract: A rack bar includes a shaft member having a toothed section. The toothed section has a plurality of rack teeth, and extends over a portion of an entire length of the shaft member along a longitudinal direction of the shaft member. The shaft member has a grinding-finished outer peripheral surface extending over the entire length of the shaft member including the toothed section. A method for manufacturing the rack bar includes forming the toothed section by plastic working and grinding the outer peripheral surface to improve shape accuracy.

Abstract: A heating method, a heating apparatus, and a method for manufacturing a press-molded article using the heating method are provided. Electrodes are placed on a workplace to extend across a heating target region in a first direction. At least one of the electrodes is moved in a second direction perpendicular to the first direction over the heating target region while applying electric current to the electrodes. A distribution of contact pressure between at least one of the electrodes and the workpiece along the first direction is adjusted, with a plurality of segment regions being defined by dividing the heating target region such that the segment regions are arranged side by side in the first direction, and in accordance with a length of each of the segment regions between the electrodes, to adjust a healing temperature of each of the segment regions of the heating target region.

Abstract: A metal core for a resin gear and a resin gear composite member are provided. The metal core includes a boss portion into which a shaft is press-fitted, a ring portion to which an outer peripheral resin is joined, and a connecting portion via which the boss portion and the ring portion are coaxially provided. The boss portion is arranged on one side of the connecting portion at an inner circumference of the connecting portion and extends annularly in an axial direction. The ring portion is arranged on the same side of the connecting portion at an outer circumference of the connecting portion and extends annularly in the axial direction. The boss portion, the connecting portion, and the ring portion are formed of an integrally continuous material. The boss portion is thicker than the connecting portion and the ring portion.