Patent application number | Description | Published |
20080241368 | TREATING SOLUTION FOR FORMING FLUORIDE COATING FILM AND METHOD FOR FORMING FLUORIDE COATING FILM - A conventional method for forming an insulating film on a magnet has a difficulty in achieving sufficient improvement in magnetic characteristics due to nonuniformity of a coating film, and an extended time and higher temperature which are required in a thermal treatment. In order to solve the problems, the present invention provides a treating solution composed of an alcohol based solvent and a rare earth fluoride or alkaline earth metal fluoride dispersing in the solvent. In the treating solution, at least one X-ray diffraction peak has a half-value width larger than 1°. The present invention also provides a method for forming an insulating film using the treating solution. | 10-02-2008 |
20080241513 | RARE EARTH MAGNET AND MANUFACTURING METHOD THEREOF - A structure of a magnet wherein a magnet consisting of a magnetic body including iron and rare earths, a plurality of fluorine compound layers or oxyfluorine compound layers are formed interior of the magnetic body, and the fluorine compound layer or oxyfluorine compound layer has a major axis which is greater than the mean particle size of the crystal grains of the magnetic body. | 10-02-2008 |
20080260564 | COMPACTED MAGNETIC CORE, PRODUCTION METHOD OF THE SAME, AND MOTOR FOR ELECTRIC VEHICLE - A manufacturing method of a magnetic core includes a first step of applying a treatment liquid for forming an insulating film to iron powder; a second step of heat-treating the iron powder to which the treatment liquid has been applied, at a temperature higher than 350 degrees; a third step of compacting the heat-treated iron powder to form a magnetic core; and a forth step of heat-treating the magnetic core at a temperature ranging from 600 degrees to 800 degrees. | 10-23-2008 |
20080317620 | Rare earth element magnet - A rare earth element magnet comprising molded magnetic powder containing at least one rare earth element, wherein a Fe rich phase covering a part or entire of the surface of particles of the magnetic powder and having a Fe atomic percentage larger than that of the magnetic powder, and an inorganic binder bonding the particles covered with the Fe rich phase. | 12-25-2008 |
20090148718 | High Resistivity Compressed Magnetic Core - A powder compressed magnetic core, which is produced by compressing iron powder or alloy powder of which the main component is iron. A fluoride compound layer of a fluoride of a rare earth element or a fluoride of an alkaline earth metal is formed on the surface of the powder, and an under layer is formed between the fluoride layer and the iron powder or the alloy powder. | 06-11-2009 |
20090200885 | Self starting permanent magnet synchronous motor - The present invention provides a permanent magnet that a fluorine compound is formed on the surfaces of Fe-based magnetic particles, and a recoil permeability is determined in a range of 1.05 to 1.30 by controlling an iron concentration in the fluorine compound to a range of 1 to 50% to reduce a loss due to magnetization rotation, thereby remedying reduction of a residual magnetic flux density and degradation of steady-state characteristics. | 08-13-2009 |
20100007232 | Sintered Magnet Motor - Disclosed herein is a sintered magnet motor having a sintered magnet rotor, the rotor comprising: a ferromagnetic material comprising iron as a main ingredient to be sintered; a fluorine compound or an oxyfluoride compound formed in the inside of a crystal grain or to a portion of a grain boundary of the ferromagnetic material; and at least one of alkalis, alkaline earth elements, and rare earth elements contained in the fluorine compound or the oxyfluoride compound; a portion of the fluorine compound or the oxyfluoride compound being distributed with a concentration gradient established from the surface to the inside of the ferromagnetic material, and a rare earth element being distributed with a concentration gradient established between the grain boundary surface and the parent phase of the ferromagnetic material, wherein the concentration distribution of the fluorine compound is asymmetrical when viewed from the pole center of the sintered magnet rotor. The amount of use of a fluorine compound can be decreased in this sintered magnet motor. | 01-14-2010 |
20100141367 | HIGH RESISTANCE MAGNET AND MOTOR USING THE SAME - A magnet comprising grains of a ferromagnetic material whose main component is iron and a fluorine compound layer or an oxy-fluorine compound layer of fluoride compound particles of alkali metals, alkaline earth metals and rare earth elements, present on the surface of the ferromagnetic material grains, wherein an amount of iron atoms in the fluorine compound particles is 1 to 50 atomic %. | 06-10-2010 |
20100194509 | RARE EARTH MAGNET - A rare earth magnet having a composition represented by RTB wherein R denotes a rare earth element, T a transition metal and B boron, the magnet being composed of magnet powder constituted by crystalline particles. The particles of the magnetic powder have a ratio of a short diameter being 10 μm or more to a long diameter is 0.5 or less. An element Rm having a magnetic anisotropy higher than that of the rare earth element is contained in the surface and inside of the magnet constituted by the magnet powder in an approximately constant concentration. An oxy-fluoride and carbon are present at boundaries of the particles of the magnet powder. | 08-05-2010 |
20100289366 | Rare Earth Magnet and Motor Using the Same - The present invention makes it possible to increase the residual magnetic flux density and the coercive force of a rare earth magnet; and raise the Curie temperature. In a magnet formed by compressing magnetic particles, the surface of a magnetic particle is covered with a metal fluoride film, the magnetic particle has a crystal structure containing a homo portion formed by bonding adjacent iron atoms and a hetero portion formed by bonding two iron atoms via an atom other than iron, and the distance between the two iron atoms in the hetero portion is different from the distance between the adjacent iron atoms in the homo portion. | 11-18-2010 |
20100297343 | TREATING AGENT FOR FORMING A FLUORIDE COATING FILM AND METHOD FOR FORMING A FLUORIDE COATING FILM - A fluoride coating film formed with a fluoride-containing solution wherein a rare earth fluoride or an alkaline earth metal fluoride, in particular, fluoride of Pr, Nd, Dy, Tb and Ho, is swollen in a solvent comprising a major amount of an alcohol, and the solution is a colloidal solution in which the rare earth fluoride or the alkaline earth metal fluoride is dispersed homogeneously in the solvent comprising a major amount of an alcohol improves magnetic properties of NdFeB rare earth magnets including not only sintered magnets but also bonded magnets. | 11-25-2010 |
20110079327 | RARE-EARTH MAGNET AND MANUFACTURING METHOD THEREOF AND MAGNET MOTOR - The object of the present invention is to provide a rare earth magnet which enables to achieve a good balance between high coercive force and high residual magnetic flux density, and its manufacturing method. The present invention provides a rare earth magnet in which a layered grain boundary phase is formed on a surface or a portion of a grain boundary of Nd | 04-07-2011 |
20110133112 | FERROMAGNETIC COMPOUND MAGNET - A ferromagnetic compound magnet in accordance with the present invention includes a ferromagnetic compound based on a binary alloy containing R—Fe system (R is a 4f transition element or Y) or a ternary allay containing R—Fe-T system (R is a 4f transition element or Y, and T is a 3d transition element except for Fe, or Mo, Nb or W), the ferromagnetic compound being characterized by: atomic percentage of the element R to the element Fe or to the elements Fe and T is 15% or lower; an element F is incorporated into an interstitial position in a crystal lattice of the alloy. The ferromagnetic compound is expressed in a chemical formula of: R | 06-09-2011 |
20110240909 | MAGNETIC MATERIAL AND MOTOR USING THE SAME - Characteristics of a magnetic material are improved without using a heavy rare earth element as a scarce resource. By incorporating fluorine into a magnetic powder and controlling the crystal orientation in crystal grains, a magnetic material securing magnetic characteristics such as coercive force and residual flux density can be fabricated. As a result, the resource problem with heavy rare earth elements can be solved, and the magnetic material can be applied to magnetic circuits that require a high energy product, including various rotating machines and voice coil motors of hard discs. | 10-06-2011 |
20110254646 | HIGH RESISTANCE MAGNET AND MOTOR USING THE SAME - A magnet comprising grains of a ferromagnetic material whose main component is iron and a fluorine compound layer or an oxy-fluorine compound layer of fluoride compound particles of alkali metals, alkaline earth metals and rare earth elements, present on the surface of the ferromagnetic material grains, wherein an amount of iron atoms in the fluorine compound particles is 1 to 50 atomic %. | 10-20-2011 |
20120025651 | SINTERED MAGNET AND ROTATING ELECTRIC MACHINE USING SAME - A sintered magnet according to the present invention is a sintered magnet configured from a magnetic powder grain having Nd | 02-02-2012 |
20120111232 | TREATING SOLUTION FOR FORMING FLUORIDE COATING FILM AND METHOD FOR FORMING FLUORIDE COATING FILM - A conventional method for forming an insulating film on a magnet has a difficulty in achieving sufficient improvement in magnetic characteristics due to nonuniformity of a coating film, and an extended time and higher temperature which are required in a thermal treatment. In order to solve the problems, the present invention provides a treating solution composed of an alcohol based solvent and a rare earth fluoride or alkaline earth metal fluoride dispersing in the solvent. In the treating solution, at least one X-ray diffraction peak has a half-value width larger than 1°. The present invention also provides a method for forming an insulating film using the treating solution. | 05-10-2012 |
20120145944 | MAGNETIC MATERIAL AND MOTOR OBTAINED USING SAME - Disclosed is a magnetic material in which 50% by volume of the magnetic particles are accounted for by the main phase of the magnet, the main phase having a Curie temperature (Curie point) of 200° C. or higher, a saturation magnetic-flux density at around 20° C. of 1.0 T (tesla) or higher, and a coercive force of 10 kOe or higher, the crystal structure of the main phase being stable up to 200° C., and in which phases other than the main phase which are present at the grain boundaries or grain surfaces have stabilized or improved the magnetic properties. This magnetic material comprises two ferromagnetic phases, i.e., a ferromagnetic compound which is composed of fluorine, iron, and one or more rare-earth elements including yttrium and ferromagnetic iron which contains fluorine, carbon, nitrogen, hydrogen, or boron. A fluoride and an oxyfluoride have been formed at some of the boundaries or surfaces of the grains of the ferromagnetic phases. | 06-14-2012 |
20120175986 | RARE-EARTH MAGNET - In a ferromagnetic material containing at least one kind of rare-earth element, a layer containing at least one kind of alkaline earth element or rare-earth element and fluorine is formed at the grain boundary or near the powder surface of the ferromagnetic material. A further layer containing at least one kind of rare-earth element, having a fluorine concentration lower than that of the layer described first and having a rare-earth element concentration higher than that of the host phase of the ferromagnetic material, or an oxide layer containing a rare-earth element is formed in adjacent with a portion of the layer described first. | 07-12-2012 |
20130069746 | Sintered Magnet - Disclosed is a sintered magnet which is a rare-earth magnet using a less amount of a rare-earth element but having a higher maximum energy product and a higher coercivity. The sintered magnet includes a NdFeB crystal; and an FeCo crystal adjacent to the NdFeB crystal through the medium of a grain boundary. The FeCo crystal includes a core and a periphery and has a cobalt concentration decreasing from the core to the periphery. The FeCo crystal has a difference in cobalt concentration of 2 atomic percent or more between the core and the periphery. In the NdFeB crystal, cobalt and a heavy rare-earth element are unevenly distributed and enriched in the vicinity of the grain boundary. | 03-21-2013 |
20130126775 | Alcoholic Solution and Sintered Magnet - The purpose of the present invention is to provide an alcoholic solvent, in which FeCo based particles becoming a soft magnetic material are improved, for enhancing properties of a magnetic material using no heavy rare earth elements, and is to provide a sintered magnet produced by using it. | 05-23-2013 |
20130162089 | Sintered Magnet Motor - A sintered magnet motor includes a rotor, a stator, and coils. Sintered magnets are disposed on the rotor. In the sintered magnet motor, a residual magnetic flux density of each of the sintered magnets is controlled by a magnetic field generated by a coil current. | 06-27-2013 |
20130278104 | Rare Earth Magnet and Motor Using the Same - The present invention makes it possible to increase the residual magnetic flux density and the coercive force of a rare earth magnet; and raise the Curie temperature. In a magnet formed by compressing magnetic particles, the surface of a magnetic particle is covered with a metal fluoride film, the magnetic particle has a crystal structure containing a homo portion formed by bonding adjacent iron atoms and a hetero portion formed by bonding two iron atoms via an atom other than iron, and the distance between the two iron atoms in the hetero portion is different from the distance between the adjacent iron atoms in the homo portion. | 10-24-2013 |