Patent application number | Description | Published |
20090090435 | Process for Producing Magnetic Powder and Process for Producing Dust Core - A process for producing a magnetic powder which is sufficiently reduced in core losses such as iron loss and hysteresis loss and has sufficient strength; and a process for producing a dust core. The process for magnetic powder production comprises using a magnetic-material powder produced by water atomization as a raw powder and subjecting the powder to spheroidizing in which a mechanical impact is applied to the powder to spheroidize the powder particles. After the spheroidizing, the powder is subjected to a grain enlarging treatment in which the powder is annealed at a temperature not lower than the austenite transformation point. The process for dust core production comprises compacting the magnetic powder thus produced. | 04-09-2009 |
20100045120 | MAGNETIC POWDER, DUST CORE, MOTOR, AND REACTOR - According to the present invention, a magnetic powder for a dust core, which is excellent in terms of insulation properties without causing a decrease in the dust core magnetic flux density, a dust core comprising the magnetic powder, and a motor or a reactor having a core composed of the dust core are provided. Therefore, a magnetic powder | 02-25-2010 |
20100079015 | DUST CORE, METHOD FOR PRODUCING THE SAME, ELECTRIC MOTOR, AND REACTOR - According to the present invention, a dust core having excellent insulating properties, high strength, and high density (high magnetic flux density), a method for producing the same, and an electric motor or reactor having a core member composed of the dust core are provided. Therefore, a method for producing a dust core is provided, such method comprising the following steps: a 1 | 04-01-2010 |
20100239879 | IRON POWDER FOR DUST CORES - Since a surface of an iron powder is covered with an oxide film composed of a Si-based oxide in which the ratio of Si to Fe satisfies Si/Fe≧0.8 on an atomic number basis, an iron powder for dust cores is provided which can be formed into a dust core having a high resistivity and hence having a low iron loss without degrading the mechanical strength. | 09-23-2010 |
20100266861 | POWDER FOR MAGNETIC CORE, POWDER MAGNETIC CORE AND THEIR PRODUCTION METHODS - A method for producing a powder for a magnetic core, in which an alkoxide film formation step and a silicone resin film formation step are carried out to form an insulation film composed of an alkoxide film and a silicone resin film on the surface of a pure iron powder, wherein the alkoxide film formation step comprises immersing a pure iron powder in an alkoxide-containing solution which is prepared by mixing a Si alkoxide having at least one organic group having a polar group comprising at least one of N, P, S and O atoms and an Al alkoxide with a dehydrated organic solvent, and drying to remove the dehydrated organic solvent, thereby forming an alkoxide film comprising an Al—Si—O type composite oxide on the surface of the pure iron powder; and the silicone resin film formation step comprises immersing the pure iron powder having the alkoxide film formed thereon in a silicone resin-containing solution which is prepared by mixing a silicone resin with an organic solvent, and drying to remove the organic solvent, thereby forming a silicone resin film on the alkoxide film. | 10-21-2010 |
20100271158 | POWDER FOR MAGNETIC CORE, METHOD FOR MANUFACTURING POWDER FOR MAGNETIC CORE, AND DUST CORE - A method for manufacturing a powder for a magnetic core including at least a process of performing a siliconizing treatment on a surface of an iron powder containing elemental carbon. In the process of siliconizing treatment, a powder containing at least a silicon dioxide is brought into contact with the surface of the iron powder, elemental silicon is detached from the silicon dioxide by heating the powder of silicon dioxide, and the siliconizing treatment is performed by causing the detached elemental silicon to permeate and diffuse into a surface layer of the iron powder. The invention provides a method for manufacturing a powder for a magnetic core, by which loss reduction is achieved. | 10-28-2010 |
20150128679 | FORWARD EXTRUSION FORGING APPARATUS AND FORWARD EXTRUSION FORGING METHOD - A forward extrusion forging apparatus includes: a die having a hollow portion whose diameter is reduced at an intermediate position; and a punch that is positioned behind a workpiece placed in the hollow portion, slides in the hollow portion, and extrudes the workpiece ahead of the hollow portion so that the workpiece is forged. An extruding surface of the punch, which extrudes the workpiece, is recessed in a direction opposite an extruding direction in a manner such that a center portion of the extruding surface is most recessed. | 05-14-2015 |
20150279559 | MANUFACTURING METHOD FOR RARE-EARTH MAGNET - Provided is a method for manufacturing a rare-earth magnet capable of manufacturing a rare-earth magnet with high degree of orientation by sufficient plastic deformation while suppressing cracks at the side faces of a compact that is plastic-deformed during the hot deformation processing. The method includes a step of preparing a compact S, preparing a plastic processing mold including a die D in which a cavity Ca is provided, and punches P that are slidable in the cavity Ca, the cavity Ca having a cross section that is larger in cross-sectional dimensions than a cross section of the compact S that is orthogonal to a pressing direction by the punches P; and a step of placing the compact S in the cavity Ca and performing hot deformation processing, thus manufacturing an orientational magnet C. Let that W | 10-01-2015 |
20160064145 | MANUFACTURING METHOD OF RARE-EARTH MAGNET - A manufacturing method of a rare-earth magnet includes: manufacturing a sintered body having by performing pressing on a magnetic powder for a rare-earth magnet; and manufacturing a rare-earth magnet by putting the sintered body in a plastic working mold and by performing hot plastic working on the sintered body while pressing the sintered body to give anisotropy to the sintered body. The sintered body has a cuboid shape and includes at least one recessed side face that has a recessed portion curved inward. The plastic working mold includes a lower die, a side die forming a rectangular frame of four side faces, and an upper die slidable in the side die. The hot plastic working is hot upsetting. | 03-03-2016 |