Patents by Inventor Tetsuya Hidaka

Tetsuya Hidaka 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).

  • Publication number: 20050183791
    Abstract: The present invention provides a method for producing a sintered magnet, which can have a sufficient sintered density even when the magnet has a low-R composition. The method is for producing a sintered magnet comprising R (R: one or more rare-earth elements), T (T: one or more transition metal elements essentially comprising Fe, or Fe and Co) and B (boron) as the main components, wherein a starting alloy prepared by strip casting is pulverized to a given particle size to form a fine powder, where the starting alloy comprises discolored deposit 1 on the surface and the area ratio of the discolored deposit 1 is 1.5% or less, the resulting fine powder is compacted in a magnetic field to prepare a compact, and the compact is sintered.
    Type: Application
    Filed: November 16, 2004
    Publication date: August 25, 2005
    Inventors: Tetsuya Hidaka, Chikara Ishizaka
  • Patent number: 6811620
    Abstract: An R—T—B system rare earth permanent magnet, which is a sintered body comprising: a main phase consisting of an R2T14B phase (wherein R represents one or more rare earth elements (providing that the rare earth elements include Y), and T represents one or more transition metal elements essentially containing Fe, or Fe and Co); and a grain boundary phase containing a higher amount of R than the above main phase, wherein a product that is rich in Zr exists in the above R2T14B phase. The product that is rich in Zr has a platy or acicular form. The R—T—B system rare earth permanent magnet containing the product enables to inhibit the grain growth, while keeping a decrease in magnetic properties to a minimum, and to obtain a wide suitable sintering temperature range.
    Type: Grant
    Filed: March 11, 2004
    Date of Patent: November 2, 2004
    Assignee: TDK Corporation
    Inventors: Chikara Ishizaka, Gouichi Nishizawa, Tetsuya Hidaka, Akira Fukuno, Nobuya Uchida
  • Publication number: 20040187970
    Abstract: An R-T-B system rare earth permanent magnet, which is a sintered body comprising: a main phase consisting of an R2T14B phase (wherein R represents one or more rare earth elements (providing that the rare earth elements include Y), and T represents one or more transition metal elements essentially containing Fe, or Fe and Co); and a grain boundary phase containing a higher amount of R than the above main phase, wherein a product that is rich in Zr exists in the above R2T14B phase. The product that is rich in Zr has a platy or acicular form. The R-T-B system rare earth permanent magnet containing the product enables to inhibit the grain growth, while keeping a decrease in magnetic properties to a minimum, and to obtain a wide suitable sintering temperature range.
    Type: Application
    Filed: March 11, 2004
    Publication date: September 30, 2004
    Applicant: TDK CORPORATION
    Inventors: Chikara Ishizaka, Gouichi Nishizawa, Tetsuya Hidaka, Akira Fukuno, Nobuya Uchida
  • Publication number: 20040187962
    Abstract: A method for manufacturing an R—T—B system rare earth permanent magnet that is a sintered body comprising a main phase consisting of an R2T14B phase (wherein R represents one or more rare earth elements (providing that the rare earth elements include Y), and T represents one or more transition metal elements essentially containing Fe, or Fe and Co), and a grain boundary phase containing a higher amount of R than the above main phase, wherein a product that is rich in Zr exists in the above R2T14B phase, the above manufacturing method comprising the steps of: preparing an R—T—B alloy containing as a main component the R2T14B phase and also containing Zr, and an R-T alloy containing R and T as main components, wherein the amount of R is higher than that of the above R—T—B alloy; obtaining a mixture of the R—T—B alloy powder and the R-T alloy powder; preparing a compacted body with a certain form from the above mixture; and sintering the above compacted body, where
    Type: Application
    Filed: March 11, 2004
    Publication date: September 30, 2004
    Applicant: TDK CORPORATION
    Inventors: Chikara Ishizaka, Gouichi Nishizawa, Tetsuya Hidaka, Akira Fukuno, Nobuya Uchida
  • Publication number: 20040187969
    Abstract: A sintered body comprising a main phase consisting of an R2T14B phase (wherein R represents one or more rare earth elements (providing that the rare earth elements include Y), and T represents one or more transition metal elements essentially containing Fe, or Fe and Co), and a grain boundary phase containing a higher amount of R than the main phase, wherein a platy or acicular product exists. This sintered body enables to inhibit the grain growth, while keeping a decrease in magnetic properties to a minimum, and to improve a suitable sintering temperature range.
    Type: Application
    Filed: March 11, 2004
    Publication date: September 30, 2004
    Applicant: TDK CORPORATION
    Inventors: Chikara Ishizaka, Gouichi Nishizawa, Tetsuya Hidaka, Akira Fukuno, Yoshinori Fujikawa
  • Publication number: 20040189426
    Abstract: An R-T-B system rare earth permanent is provided, which comprises a sintered body comprising: an R2T14B phase (wherein R represents one or more rare earth elements (providing that the rare earth elements include Y) and T represents one or more transition metal elements essentially containing Fe, or Fe and Co) as a main phase; and a grain boundary phase containing a higher amount of R than the above main phase, wherein, when Pc (permeance coefficient) is 2, if a total flux is defined as f1 under the application of an effective magnetic field of 240 kA/m (providing that an effective magnetic field=an applied magnetic field−a demagnetizing field, and each value of them is absolute value), if a total flux is defined as f2 under the application of an effective magnetic field of 800 kA/m, and if a total flux is defined as f3 under the application of an effective magnetic field of 2,000 kA/m, a magnetization rate a (=f1/f3×100) is 40% or more, and a magnetization rate b (=f2/f3×
    Type: Application
    Filed: March 24, 2004
    Publication date: September 30, 2004
    Applicant: TDK CORPORATION
    Inventors: Tetsuya Hidaka, Kazuya Sakamoto, Kazuo Sato, Hironari Okada
  • Publication number: 20040177899
    Abstract: A sintered body with a composition consisting of 25% to 35% by weight of R (wherein R represents one or more rare earth elements, provided that the rare earth elements include Y), 0.5% to 4.5% by weight of B, 0.02% to 0.6% by weight of Al and/or Cu, 0.03% to 0.25% by weight of Zr, 4% or less by weight (excluding 0) of Co, and the balance substantially being Fe. This sintered body has a coefficient of variation (CV value) showing the dispersion degree of Zr of 130 or less. In addition, this sintered body has a grain boundary phase comprising a region that is rich both in at least one element selected from a group consisting of Cu, Co and R, and in Zr. This sintered body enables to inhibit the grain growth, while keeping the decrease of magnetic properties to a minimum, and to improve the suitable sintering temperature range.
    Type: Application
    Filed: September 29, 2003
    Publication date: September 16, 2004
    Applicant: TDK CORPORATION
    Inventors: Gouichi Nishizawa, Chikara Ishizaka, Tetsuya Hidaka, Akira Fukuno, Yoshinori Fujikawa
  • Publication number: 20040166013
    Abstract: When an R-T-B system rare earth permanent magnet is obtained by a mixing method to obtain a sintered body with a composition consisting essentially of 25% to 35% by weight of R (wherein R represents one or more rare earth elements, providing that the rare earth elements include Y), 0.5% to 4.5% by weight of B, 0.02% to 0.6% by weight of Al and/or Cu, 0.03% to 0.25% by weight of Zr, 4% or less by weight (excluding 0) of Co, and the balance substantially being Fe, wherein a coefficient of variation (CV) showing the dispersion of Zr is 130 or lower, Zr is contained in a low R alloy. This sintered body enables to inhibit the grain growth, while keeping the decrease of magnetic properties to a minimum, and to improve the suitable sintering temperature range.
    Type: Application
    Filed: September 29, 2003
    Publication date: August 26, 2004
    Applicant: TDK CORPORATION
    Inventors: Gouichi Nishizawa, Chikara Ishizaka, Tetsuya Hidaka, Akira Fukuno
  • Publication number: 20040118484
    Abstract: A sintered body with a composition consisting of 25% to 35% by weight of R (wherein R represents one or more rare earth elements, providing that the rare earth elements include Y), 0.5% to 4.5% by weight of B, 0.02% to 0.6% by weight of Al and/or Cu, 0.03% to 0.25% by weight of Zr, 4% or less by weight (excluding 0) of Co, and the balance substantially being Fe, wherein a coefficient of variation (CV) showing the dispersion of Zr is 130 or lower. This sintered body enables to inhibit the grain growth, while keeping the decrease of magnetic properties to a minimum, and to improve the suitable sintering temperature range.
    Type: Application
    Filed: September 29, 2003
    Publication date: June 24, 2004
    Applicant: TDK CORPORATION
    Inventors: Gouichi Nishizawa, Chikara Ishizaka, Tetsuya Hidaka, Akira Fukuno
  • Patent number: 6696223
    Abstract: A method for generating a photoresist pattern on top of an object that includes a layer of material that is opaque to light of a predetermined wavelength. The object is first covered with a layer of photoresist material. The layer of photoresist material is then irradiated with light of the predetermined wavelength from a position under the object such that the object casts a shadow into the layer of photoresist. The photoresist material is then developed to generate the photoresist pattern. The layer of photoresist material is irradiated from below the object by providing a reflecting surface below the object and a light source above the object. A mask is positioned between the object and the light source such that the mask casts a shadow that covers the object and a portion of the area surrounding the object.
    Type: Grant
    Filed: August 16, 2001
    Date of Patent: February 24, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Tetsuya Hidaka, Yawara Kaneko
  • Patent number: 6674934
    Abstract: Pressure-actuated bi-stable optical switching is provided. In this regard, a pressure-actuated bi-stable optical switch includes an optical path and a cavity intersecting the optical path. The cavity defines a first position along the optical path and a second position displaced from the optical path. An index-matching liquid, which exhibits an index of refraction closer to an index of refraction of the optical path than to that of a vacuum, is arranged within the cavity. A pressure generator generates pressure that selective moves the liquid between the first and second positions. Additionally, a potential profile maintains the liquid in the one of the first and second positions to which it was most recently moved while the pressure generator is not generating pressure. Methods, systems and other switches also are provided.
    Type: Grant
    Filed: November 6, 2001
    Date of Patent: January 6, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Kent W. Carey, Tetsuya Hidaka, You Kondoh, Mitsuchika Saito, Tsutomu Takenaka
  • Publication number: 20030086637
    Abstract: Pressure-actuated bi-stable optical switching is provided. In this regard, a pressure-actuated bi-stable optical switch includes an optical path and a cavity intersecting the optical path. The cavity defines a first position along the optical path and a second position displaced from the optical path. An index-matching liquid, which exhibits an index of refraction closer to an index of refraction of the optical path than to that of a vacuum, is arranged within the cavity. A pressure generator generates pressure that selective moves the liquid between the first and second positions. Additionally, a potential profile maintains the liquid in the one of the first and second positions to which it was most recently moved while the pressure generator is not generating pressure. Methods, systems and other switches also are provided.
    Type: Application
    Filed: November 6, 2001
    Publication date: May 8, 2003
    Inventors: Kent W. Carey, Tetsuya Hidaka, You Kondoh, Mitsuchika Saito, Tsutomu Takenaka
  • Publication number: 20020001779
    Abstract: A method for generating a photoresist pattern on top of an object that includes a layer of material that is opaque to light of a predetermined wavelength. The object is first covered with a layer of photoresist material. The layer of photoresist material is then irradiated with light of the predetermined wavelength from a position under the object such that the object casts a shadow into the layer of photoresist. The photoresist material is then developed to generate the photoresist pattern. The layer of photoresist material is irradiated from below the object by providing a reflecting surface below the object and a light source above the object. A mask is positioned between the object and the light source such that the mask casts a shadow that covers the object and a portion of the area surrounding the object.
    Type: Application
    Filed: August 16, 2001
    Publication date: January 3, 2002
    Inventors: Tetsuya Hidaka, Yawara Kaneko
  • Patent number: 5916376
    Abstract: An object of the invention is to provide an inexpensive magnet having a high coercivity, high squareness ratio and high maximum energy product. According to the invention, a magnet containing R, T, N, and M wherein R is at least one rare earth element with essential samarium, T is iron or iron and cobalt, and M is at least one element of Ti, V, Cr, Nb, Hf, Ta, Mo, W, Al, C, and P, with essential zirconium, in amounts of 4-8 at % of R, 10-20 at % of N, 2-10 at % of M, and having a hard magnetic phase (TbCu.sub.7 type crystalline phase) and a soft magnetic phase (which is a bcc structured T phase, has an average grain diameter of 5-60 nm, and accounts for 10 to 60% by volume of the entirety), the atomic ratio (R+M)/(R+T+M) in the hard magnetic phase being in excess of 12.5%, is prepared utilizing a single roll technique. In the single roll technique, the peripheral speed of a chill roll is at least 50 m/s, and the discharge pressure of the molten alloy is 0.3-2 kgf/cm.sup.2.
    Type: Grant
    Filed: December 4, 1997
    Date of Patent: June 29, 1999
    Assignee: TDK Corporation
    Inventors: Akira Fukuno, Tomomi Yamamoto, Tetsuhito Yoneyama, Tetsuya Hidaka
  • Patent number: 5750044
    Abstract: A magnet consists essentially of 4-8 at % of R, 10-20 at % of N, 2-10 at % of M, and the balance of T wherein R is at least one rare earth element, Sm being present in R in a proportion of at least 50 at %, T is Fe or Fe and Co, M is Zr with or without partial replacement by at least one element of Ti, V, Cr, Nb, Hf, Ta, Mo, W, Al, C, and P. Contained in the magnet are a hard magnetic phase based on R, T, and N and containing at least one crystalline phase selected from TbCu.sub.7, Th.sub.2 Zn.sub.17, and Th.sub.2 Ni.sub.17 types and a soft magnetic phase consisting of a T phase having a bcc structure, the soft magnetic phase having a mean grain size of 5-60 nm and being present in a proportion of 10-60% by volume. This construction ensures high coercivity, high squareness ratio, and high maximum energy product.
    Type: Grant
    Filed: July 11, 1995
    Date of Patent: May 12, 1998
    Assignee: TDK Corporation
    Inventors: Tetsuhito Yoneyama, Tomomi Yamamoto, Tetsuya Hidaka, Akira Fukuno