Patents by Inventor Tadao Nomura
Tadao Nomura has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 8277578Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.Type: GrantFiled: October 27, 2010Date of Patent: October 2, 2012Assignee: Shin-Etsu Chemical Co., Ltd.Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
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Patent number: 8252123Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.Type: GrantFiled: October 27, 2010Date of Patent: August 28, 2012Assignee: Shin-Etsu Chemical Co., Ltd.Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
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Publication number: 20120132130Abstract: A method of producing a SiC single crystal includes: disposing a SiC seed crystal at a bottom part inside a graphite crucible; causing a solution containing Si, C and R (R is at least one selected from the rare earth elements inclusive of Sc and Y) or X (X is at least one selected from the group consisting of Al, Ge, Sn, and transition metals exclusive of Sc and Y) to be present in the crucible; supercooling the solution so as to cause the SiC single crystal to grow on the seed crystal; and adding powdery or granular Si and/or SiC raw material to the solution from above the graphite crucible while keeping the growth of the SiC single crystal.Type: ApplicationFiled: November 21, 2011Publication date: May 31, 2012Applicant: SHIN-ETSU CHEMICAL CO., LTD.Inventors: Tadao Nomura, Norio Yamagata, Takehisa Minowa
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Patent number: 8025744Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.Type: GrantFiled: March 17, 2008Date of Patent: September 27, 2011Assignee: Shin-Etsu Chemical Co., Ltd.Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
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Publication number: 20110191016Abstract: Map data is disclosed. The map data includes a multilink information list, a road information list and an offset information list. The multilink information list stores fixed-length multilink information elements while multilinks are prescribed in such manner that when groups of links have the same attribute, the groups are collectively defined as a same multilink. Each multilink information element indicates a number of links contained in a corresponding multilink. The road information list stores therein road information elements each indicative of road information of a corresponding multilinks. The offset information list stores therein fixed-length offset information elements each indicative of location of a corresponding road information elements in the road information.Type: ApplicationFiled: January 26, 2011Publication date: August 4, 2011Applicant: DENSO CORPORATIONInventors: Tadao NOMURA, Takayuki Matsunaga
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Patent number: 7985303Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.Type: GrantFiled: October 27, 2010Date of Patent: July 26, 2011Assignee: Shin-Etsu Chemical Co., Ltd.Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
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Publication number: 20110090032Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.Type: ApplicationFiled: October 27, 2010Publication date: April 21, 2011Applicant: SHIN-ETSU CHEMICAL CO., LTD.Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
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Publication number: 20110036459Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.Type: ApplicationFiled: October 27, 2010Publication date: February 17, 2011Applicant: SHIN-ETSU CHEMICAL CO., LTD.Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
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Publication number: 20110036458Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.Type: ApplicationFiled: October 27, 2010Publication date: February 17, 2011Applicant: SHIN-ETSU CHEMICAL CO., LTD.Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
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Publication number: 20110036460Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.Type: ApplicationFiled: October 27, 2010Publication date: February 17, 2011Applicant: SHIN-ETSU CHEMICAL CO., LTD.Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
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Publication number: 20110036457Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.Type: ApplicationFiled: October 27, 2010Publication date: February 17, 2011Applicant: SHIN-ETSU CHEMICAL CO., LTD.Inventors: Hiroaki Nagata, Tadao Nomura, Takehisa Minowa
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Publication number: 20110000586Abstract: A rare earth magnet is prepared by disposing a R1-T-B sintered body comprising a R12T14B compound as a major phase in contact with an R2-M alloy powder and effecting heat treatment for causing R2 element to diffuse into the sintered body. The alloy powder is obtained by quenching a melt containing R2 and M. R1 and R2 are rare earth elements, T is Fe and/or Co, M is selected from B, C, P, Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ag, In, Sn, Sb, Hf, Ta, W, Pt, Au, Pb, and Bi.Type: ApplicationFiled: June 29, 2010Publication date: January 6, 2011Applicant: SHIN-ETSU CHEMICAL CO., LTD.Inventors: Tadao Nomura, Hiroaki Nagata, Takehisa Minowa
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Publication number: 20080223489Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.Type: ApplicationFiled: March 17, 2008Publication date: September 18, 2008Applicant: SHIN-ETSU CHEMICAL CO., LTD.Inventors: Hiroaki NAGATA, Tadao NOMURA, Takehisa MINOWA
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Patent number: 7090730Abstract: An R—Fe—B base sintered magnet having a composition of 12–17 at % of R (wherein R stands for at least two of yttrium and rare earth elements and essentially contains Nd and Pr), 0.1–3 at % of Si, 5–5.9 at % of B, 0–10 at % of Co, and the balance of Fe, containing a R2(Fe,(Co),Si)14B intermetallic compound primary phase and at least 1% by volume of an R—Fe(Co)—Si grain boundary phase, and being free of a B-rich phase exhibits a coercive force of at least 10 kOe despite a reduced content of heavy rare earth.Type: GrantFiled: November 13, 2003Date of Patent: August 15, 2006Assignee: Shin-Etsu Chemical Co., Ltd.Inventors: Tadao Nomura, Takehisa Minowa
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Publication number: 20040094237Abstract: An R—Fe—B base sintered magnet having a composition of 12-17 at % of R (wherein R stands for at least two of yttrium and rare earth elements and essentially contains Nd and Pr), 0.1-3 at % of Si, 5-5.9 at % of B, 0-10 at % of Co, and the balance of Fe, containing a R2(Fe,(Co),Si)14B intermetallic compound primary phase and at least 1% by volume of an R—Fe(Co)—Si grain boundary phase, and being free of a B-rich phase exhibits a coercive force of at least 10 kOe despite a reduced content of heavy rare earth.Type: ApplicationFiled: November 13, 2003Publication date: May 20, 2004Inventors: Tadao Nomura, Takehisa Minowa
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Patent number: 6589367Abstract: Disclosed is a magnetically anisotropic rare earth-based permanent magnet having a nanocomposite structure consisting of fine dispersion of a magnetically hard phase, e.g., Nd2Fe14B, in alignment relative to the easy magnetization axis, a magnetically soft phase and a non-magnetic phase having a melting point lower than those of the magnetically hard and soft phases. The permanent magnet is prepared in a process in which a quenched thin magnet alloy ribbon having a composition capable of forming a magnetically hard phase, magnetically soft phase and non-magnetic phase by a heat treatment is subjected to a heat treatment in a magnetic field of at least 3 T at a temperature not lower than the melting point of the non-magnetic phase so that the liquid phase formed from the non-magnetic phase serves to facilitate rotating orientation of the magnetically hard grains to be aligned in the direction of the magnetic field relative to the easy magnetization axis.Type: GrantFiled: December 18, 2001Date of Patent: July 8, 2003Assignee: Shin-Etsu Chemical Co., Ltd.Inventors: Tadao Nomura, Ken Ohashi
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Publication number: 20020121315Abstract: Disclosed is a magnetically anisotropic rare earth-based permanent magnet having a nanocomposite structure consisting of fine dispersion of a magnetically hard phase, e.g., Nd2Fe14B, in alignment relative to the easy magnetization axis, a magnetically soft phase and a non-magnetic phase having a melting point lower than those of the magnetically hard and soft phases. The permanent magnet is prepared in a process in which a quenched thin magnet alloy ribbon having a composition capable of forming a magnetically hard phase, magnetically soft phase and non-magnetic phase by a heat treatment is subjected to a heat treatment in a magnetic field of at least 3 T at a temperature not lower than the melting point of the non-magnetic phase so that the liquid phase formed from the non-magnetic phase serves to facilitate rotating orientation of the magnetically hard grains to be aligned in the direction of the magnetic field relative to the easy magnetization axis.Type: ApplicationFiled: December 18, 2001Publication date: September 5, 2002Inventors: Tadao Nomura, Ken Ohashi
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Patent number: 6319334Abstract: Disclosed is a method for the preparation of a magnetically anisotropic rare earth/iron/boron-based permanent magnet in a relatively bulky form having a nanocomposite structure as prepared from quenched thin ribbons of the alloy. The method comprises heating the powder of quenched thin ribbons to a temperature allowing partial formation of a liquid phase of a lanthanum/iron or rare earth/copper alloy of low melting point and subjecting the powder of the quenched thin ribbons to a uniaxial hot-deformation treatment by passing the powder under resistance heating through a gap between a pair of compression rollers.Type: GrantFiled: December 16, 1999Date of Patent: November 20, 2001Assignee: Shin-Etsu Chemical Co., Ltd.Inventors: Ken Ohashi, Tadao Nomura
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Patent number: 6261385Abstract: Disclosed is a novel magnetically anisotropic rare earth-based permanent magnet having a nanocomposite structure consisting of a hard magnetic phase such as Nd2Fe14B and a soft magnetic phase such as bcc-iron, Fe3B and Fe2B in a volume ratio of 10:90 to 90:10 uniformly dispersed each in the other in a fineness of a few tens nanometers, in which particles of the hard magnetic phase are aligned in a direction relative to the easy magnetization axes of the particles. Such an anisotropic permanent magnet can be prepared by the method comprising: preparing a starting amorphous alloy of a composition susceptible to dispersion precipitation of the hard magnetic phase, for example, by the melt-spun method; forming the amorphous alloy into a magnet block; heating the magnet block at 600 to 1000° C.Type: GrantFiled: September 16, 1998Date of Patent: July 17, 2001Assignee: Shin-Etsu Chemical Co., Ltd.Inventors: Tadao Nomura, Ken Ohashi
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Patent number: 6078237Abstract: Disclosed is a rare earth-based, magnetically anisotropic permanent magnet material consisting of a rare earth element, e.g., neodymium or praseodymium, iron optional in combination with cobalt and boron and having excellent magnetic properties by virtue of the magnetic coupling between the magnetically hard and soft phases. The magnet material has a structure consisting of crystalline particles of, e.g., Nd.sub.2 Fe.sub.14 B, having a particle diameter of 1 .mu.m or larger and fine crystals of iron of submicron size in a rod-shaped or platelet form precipitated within each crystalline particle of Nd.sub.2 Fe.sub.14 B. This magnet material can be prepared by several different methods including, for example, a solid phase reaction of an intermetallic compound of Nd.sub.2 Fe.sub.17 with boron to effect a double decomposition reaction producing Nd.sub.2 Fe.sub.14 B and iron.Type: GrantFiled: December 22, 1998Date of Patent: June 20, 2000Assignee: Shin-Etsu Chemical Co., Ltd.Inventors: Tadao Nomura, Ken Ohashi, Takehisa Minowa, Yoshio Tawara, Masaru Ito