Patents Assigned to Daido Tokushuko Kabushiki Kaisha
  • Patent number: 7730755
    Abstract: The present invention relates to a process of producing a permanent magnet, which includes extruding a preform to form a plate-shaped permanent magnet, in which the preform is extruded in such a way that a dimension of a cross section of the preform is reduced in an X-direction and enlarged in a Y-direction perpendicular to the X-direction. The present invention also relates to a plate-shaped permanent magnet formed by extruding a preform, in which the preform is extruded in such a way that a dimension of a cross section of the preform is reduced in an X-direction and enlarged in a Y-direction perpendicular to the X-direction, whereby the permanent magnet has a strain ratio ?2/?1 with respect to the preform in a range of 0.2 to 3.5, in which ?1 is a strain in the direction of the extrusion of the preform and ?2 is a strain in the Y-direction.
    Type: Grant
    Filed: August 31, 2007
    Date of Patent: June 8, 2010
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventors: Junichi Esaki, Hiroaki Yoshida, Sachihiro Isogawa
  • Patent number: 7722801
    Abstract: The vacuum carburizing apparatus introduces a carburizing gas into a carburizing chamber to subject the treatment material to vacuum carburizing. The vacuum carburizing apparatus comprises a carburizing chamber that houses a treatment material therein, a vacuum pump that exhausts gas from the carburizing chamber inside to obtain vacuum, a carburizing gas supply unit that supplies carburizing gas into the carburizing chamber in pulse mode, a reflux pipe which connects an intake side of the vacuum pump and an exhaust side of the vacuum pump, an opening and closing valve which is provided on the way of the reflux pipe, and a control unit which opens the opening and closing valve when a supply of the carburizing gas into the carburizing chamber is started, wherein the control unit closes the opening and closing valve when the supply ends.
    Type: Grant
    Filed: August 29, 2007
    Date of Patent: May 25, 2010
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventor: Kenjiro Sato
  • Publication number: 20100068669
    Abstract: The present invention provides a continuous heat treatment furnace including: a heating chamber heating a treatment object in an inert gas atmosphere; a front chamber provided at one end of the heating chamber; and a first cooling chamber cooling the treatment object in an inert gas atmosphere, a vacuum purge chamber, and a second cooling chamber cooling the treatment object in an oxidizing gas atmosphere, which are connected in this order to the other end of the heating chamber, in which the treatment object transferred from the front chamber to the heating chamber is subjected to the heating in the heating chamber, and then subjected to one cooling selected from the cooling in the inert gas atmosphere in the first cooling chamber and the cooling in the oxidizing gas atmosphere in the second cooling chamber depending on a type of the treatment object.
    Type: Application
    Filed: September 15, 2009
    Publication date: March 18, 2010
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Takashi ISHIMOTO, Takaya Ochiai, Kenji Shimizu, Masato Ogawa
  • Publication number: 20100003156
    Abstract: The present invention provides a rare earth magnet, which is formed through at least hot molding, the rare earth magnet containing grains including an R2X14B phase as a main phase, and a grain boundary phase surrounding peripheries of the grains, in which R is at least one element selected from the group consisting of Nd, Pr, Dy, Tb and Ho, and X is Fe or Fe with a part being substituted by Co; in which an element RH is more concentrated in the grain boundary phase than in the grains, in which the element RH is at least one element selected from the group consisting of Dy, Tb and Ho; and the element RH is present with a substantially constant concentration distribution from the surface part of the magnet to the central part of the magnet.
    Type: Application
    Filed: June 30, 2009
    Publication date: January 7, 2010
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Shunji SUZUKI, Hayato HASHINO, Masahiro HIRAOKA, Takao YABUMI
  • Patent number: 7597987
    Abstract: An Au plated film 12 is formed on the surface of a plate-formed metal base 13 composed of a metal less noble than Au, and the product is cut along a planned cutting line 18 reflecting a contour of a desired component, to thereby form a separator 10. Thus-formed separator 10 has the Au plated film 12 formed on the main surface 10a thereof, and has a cutting plane 16 formed as an end face 16 stretched up to the main surface 10a. The metal base 13 exposes in a part of the cutting plane 16, in a width of the exposed region of 1 mm or less. This is successful in providing a metal component for fuel cell which is satisfactory in the corrosion resistance and allows easy fabrication at low costs, a method of manufacturing the same, and also in providing a fuel cell having thus-fabricated metal component for fuel cell.
    Type: Grant
    Filed: August 19, 2003
    Date of Patent: October 6, 2009
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventors: Shinobu Takagi, Masaki Shinkawa, Mikio Ura, Shinichi Yagi, Yasushi Kaneta, Tatsuo Hisada
  • Publication number: 20090206973
    Abstract: The present invention provides a bond magnet for direct current reactor which is to be disposed in a gap formed in a magnetic core of a direct current rector, the bond magnet containing a magnet powder containing a rapidly quenched powder of a rare earth magnet alloy. The present invention also provides a direct current reactor including a magnetic core having a gap and a winding area wound around the magnetic core, in which the bond magnet is disposed in the gap of the magnetic core.
    Type: Application
    Filed: February 18, 2009
    Publication date: August 20, 2009
    Applicants: DAIDO TOKUSHUKO KABUSHIKI KAISHA, KURUTAKE ELECTRO-STEEL CO., LTD.
    Inventors: Takao Yabumi, Koji Tsuru
  • Publication number: 20090165595
    Abstract: The invention provides a hard-particle powder for sintered body, which contains, by mass %, 2% to 3.5% of Si, 6% to 10% of Cr, 20% to 35% of Mo, 0.01% to 0.5% of REM, and the remainder being Co and unavoidable impurities. The invention further provides a sintered body obtained through a mixing step of mixing the above-mentioned hard-particle powder for sintered body with a pure iron powder and a graphite powder to obtain a powder mixture, a forming step of compacting the powder mixture to obtain a compact, and a sintering step of sintering the compact. The hard-particle powder according to the invention has the effect of giving a sintered body having improved wear resistance without substantially impairing powder characteristics and sintering characteristics. Additionally, the sintered body according to the invention has the effect of having excellent wear resistance.
    Type: Application
    Filed: December 19, 2008
    Publication date: July 2, 2009
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Tomomi Yamamoto, Seiji Kurata
  • Publication number: 20090136824
    Abstract: The present invention provides a metallic bipolar plate for fuel cells, including: a pair of metallic plates for fuel cells each including a substrate which contains a stainless steel, an Fe—Ni based alloy or an Ni-base alloy, has a front surface and a back surface, and has a plurality of channels of a reaction gas formed on the front surface; and a brazed portion joining the back surfaces of the substrates in such a way that the pair of metallic plates are made to face each other, wherein, in the pair of metallic plates, a thin layer of a noble metal is coated on an entirety of the front surface of each of the substrates or on at least a part of a convex portion between the plurality of channels of a reaction gas on the front surface of each of the substrates, and another thin layer of a noble metal having a thickness of from 0.
    Type: Application
    Filed: November 26, 2008
    Publication date: May 28, 2009
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Shinobu Takagi, Tatsuo Hisada, Shinichi Yagi
  • Publication number: 20090107587
    Abstract: The present invention provides a tool steel containing, by mass percent, 0.55 to 0.85% of C, 0.20 to 2.50% of Si, 0.30 to 1.20% of Mn, 0.50% or less of Cu, 0.01 to 0.50% of Ni, 6.00 to 9.00% of Cr, 0.1 to 2.00% of Mo+0.5 W, and 0.01 to 0.40% of V, with the balance of Fe and inevitable impurities, in which, when an area rate of a coarse carbide having a circle equivalent diameter of 2 pm or more in a cross section parallel to a forging direction is represented by L(%) and an area rate of the coarse carbide in a cross section perpendicular to the forging direction is represented by T(%), the area rate L is 0.001% or more, the area rate T is 0.001% or more, and the ratio L/T is within a range from 0.90 to 3.00. The tool steel of the invention exhibits an isotropic size change in quenching and tempering.
    Type: Application
    Filed: October 30, 2008
    Publication date: April 30, 2009
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventor: Takayuki Shimizu
  • Publication number: 20090074606
    Abstract: The present invention relates to a low density titanium alloy, containing: 7.1 to 10.0 mass % of Al; 0.1 to 3.0 mass % of Fe; 0.01 to 0.3 mass % of O; 0.5 mass % or less of N; 0.5 mass % or less of C; and a remainder being Ti and inevitable impurities; a golf club head using the alloy; and a production method for a low density titanium alloy part using the alloy. The alloy of the invention may further contain 0.01 to 2.0 mass % of V. The alloy of the invention has higher specific strength as compared to the Ti-6Al-4V alloy, is excellent in hot workability, and is reduced in cost.
    Type: Application
    Filed: September 12, 2008
    Publication date: March 19, 2009
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Michiharu Ogawa, Toshiharu Noda
  • Patent number: 7494618
    Abstract: To provide an alloy tool steel having high-temperature strength at an operating temperature of the order of 700° C., while maintaining room-temperature strength as high as that of a conventional matrix high-speed tool steel. The steel contains from 0.45 wt % to 0.65 wt % C, from 0.10 wt % to 1.00 wt % Si, from 0.20 wt % to 2.00 wt % Mn, not more than 0.020 wt % P, not more than 0.015 wt % S, not more than 1.00 wt % Cu, not more than 1.00 wt % Ni, from 3.50 wt % to 5.00 wt % Cr, from 0.00 wt % to 3.00 wt % Mo, from 0.00 wt % to 10.00 wt % W, from 1.00 wt % to 2.00 wt % V, from 0.00 wt % to 8.00 wt % Co, not more than 0.10 wt % Al, not more than 0.01 wt % O, not more than 0.02 wt % N, and the balance substantially constituted of Fe and unavoidable impurities, in which Weq is from 2.0 to 10.0, 2Mo/Weq is not more than 0.60, and ?C is from ?0.3 to 0.0.
    Type: Grant
    Filed: December 7, 2004
    Date of Patent: February 24, 2009
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventor: Kozo Ozaki
  • Publication number: 20080274007
    Abstract: The present invention relates a high-strength nonmagnetic stainless steel, containing, by weight percent, 0.01 to 0.06% of C, 0.10 to 0.50% of Si, 20.5 to 24.5% of Mn, 0.040% or less of P, 0.010% or less of S, 3.1 to 6.0% of Ni, 0.10 to 0.80% of Cu, 20.5 to 24.5% of Cr, 0.10 to 1.50% of Mo, 0.0010 to 0.0050% of B, 0.010% or less of O, 0.65 to 0.90% of N, and the remainder being Fe and inevitable impurities; the steel satisfying the following formulae (1) to (4): [Cr]+3.3×[Mo]+16×[N]?30, ??(1) {Ni}/{Cr}?0.15, ??(2) 2.0?[Ni]/[Mo]?30.0, and ??(3) [C]×1000/[Cr]?2.5, ??(4) wherein [Cr], [Mo], [N], [Ni], [Mo] and [C] represent the content of Cr, the content of Mo, the content of N, the content of Ni, the content of Mo and the content of C in the steel, respectively, and {Ni} represents the sum of [Ni], [Cu] and [N], and {Cr} represents the sum of [Cr] and [Mo].
    Type: Application
    Filed: May 2, 2008
    Publication date: November 6, 2008
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Koichi Ishikawa, Tetsuya Shimizu
  • Publication number: 20080264526
    Abstract: The invention provides a hot-working die steel for die-casting obtainable by quenching a steel comprising, in terms of % by mass, C: 0.1 to 0.3%, Si: 0.1 to 1.5%, Mn: 0.3 to 2%, Cr: 6 to 12%, P: 0.05% or less, S: 0.01% or less, Mo: 1 to 3%, V: 0.5 to 1.5%, s-Al: 0.005 to 0.025%, N: 0.005 to 0.025%, and O: 0.005% or less, with the remainder being Fe and inevitable impurities, followed by tempering the steel at a temperature of 500° C. or lower.
    Type: Application
    Filed: April 27, 2007
    Publication date: October 30, 2008
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventor: Koichiro Inoue
  • Publication number: 20080247901
    Abstract: The present invention relates to a mechanical part, which is obtained by: processing a steel into a shape of a part, the steel having an alloy composition containing, by weight percent, C: 0.10 to 0.30%, Si: 0.50 to 3.00%, Mn: 0.30 to 3.00%, P: 0.030% or less, S: 0.030% or less, Cu: 0.01 to 1.00%, Ni: 0.01 to 3.00%, Cr: 0.20 to 1.00%, Al: 0.20% or less, N: 0.05% or less, and the remainder of Fe and inevitable impurities, and the alloy composition satisfying the following condition: [Si %]+[Ni %]+[Cu %]?[Cr %]>0.50, in which [Si %], [Ni %], [Cu %] and [Cr %] represent the concentration of Si, the concentration of Ni, the concentration of Cu and the concentration of Cr in the alloy composition, respectively; subjecting the steel to a carburizing treatment in a vacuum, followed by gradually cooling the steel; and subsequently subjecting the steel to a high-frequency hardening to thereby harden a surface of the steel.
    Type: Application
    Filed: April 8, 2008
    Publication date: October 9, 2008
    Applicants: DAIDO TOKUSHUKO KABUSHIKI KAISHA, AISIN AW CO., LTD
    Inventors: Toshiyuki Morita, Kouji Ohbayashi, Masaki Kuwabara, Taro Matsukawa, Yutaka Eto, Kohki Mizuno
  • Publication number: 20080240970
    Abstract: The present invention relates to an austenitic free-cutting stainless steel, containing: by weight percent, 0.500% or less of C; 0.01 to 5.00% of Si; 0.01 to 10.00% of Mn; 5.00 to 25.00% of Ni; 7.50 to 30.00% of Cr; 0.300% or less of N; more than 0.0100% but not more than 0.1000% of 0; 0.0020 to 0.1000% of B; 0.300% or less of Al; and the remainder of Fe and inevitable impurities, the steel satisfying the following formula (1): 0.68?[O]/[B]?2.50 ??(1) in which [O] represents the content of O and [B] represents the content of B.
    Type: Application
    Filed: March 31, 2008
    Publication date: October 2, 2008
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Hisao Eto, Tetsuya Shimizu
  • Patent number: 7402275
    Abstract: A powder body melting burner which injects a powder body, fuel and oxygen into a furnace individually from a burner head and melts the powder body in flames in which the fuel is burned under oxygen support. The burner includes a single powder body injection hole provided in the center of the burner head, a plurality of fuel injection holes disposed at a predetermined central angle in the radial direction centered on the powder body injection hole, a single primary oxygen injection bole provided concentrically which each of the fuel injection holes, a plurality of second oxygen injection holes ranged in large numbers at a predetermined interval so as to enclose each of the powder injection boles and the fuel injection holes with the plurality of secondary oxygen injection holes forming a ring shape as a whole and a cooling chamber provided on the back side of the burner head.
    Type: Grant
    Filed: November 23, 2005
    Date of Patent: July 22, 2008
    Assignees: Daido Tokushuko Kabushiki Kaisha, Daido Ecomet Kabushiki Kaisha
    Inventors: Wataru Sato, Toshiki Watanabe, Tetsuo Okamoto
  • Publication number: 20080143634
    Abstract: According to the ultrawideband communication antenna, since surfaces of the antenna element are coated with the first resin layer and the second resin layer each of which is mixed with the nonmagnetic metal powder and has an insulating property and a high specific inductive capacity, the size is largely reduced. Further, since the nonmagnetic metal powder is used, the first resin layer and the second resin layer are free from a loss of magnetism generated therein, thereby enabling to maintain a loss of the antenna to a low level.
    Type: Application
    Filed: August 6, 2007
    Publication date: June 19, 2008
    Applicants: DAIDO TOKUSHUKO KABUSHIKI KAISHA, TOKYO INSTITUTE OF TECHNOLOGY
    Inventors: Kazuhisa Tsutsui, Yoshifumi Matui, Akihiko Saito, Mikiko Fukase, Takahiro Aoyagi
  • Patent number: 7381369
    Abstract: Provided is free cutting alloy excellent in machinability, preserving various characteristics as alloy. The free cutting alloy contains: one or more of Ti and Zr as a metal element component; and C being an indispensable element as a bonding component with the metal element component, wherein a (Ti,Zr) based compound including one or more of S, Se and Te is formed in a matrix metal phase. The free cutting alloy is more excellent in machinability, preserving various characteristics as alloy at similar levels to a conventional case. The effect is especially conspicuous, for example, when a compound expressed in a chemical form of (Ti,Zr)4C2(S,Se,Te)2 as the (Ti,Zr) based compound is formed at least in a dispersed state in the alloy structure.
    Type: Grant
    Filed: May 18, 2004
    Date of Patent: June 3, 2008
    Assignees: Daido Tokushuko Kabushiki Kaisha, Tohoku Tokushuko Kabushiki Kaisha, Japan Industrial Technology Association, Tohoku Technoarch Co., Ltd.
    Inventors: Kiyohito Ishida, Katsunari Oikawa, Takashi Ebata, Tetsuya Shimizu, Michio Okabe
  • Publication number: 20080089804
    Abstract: The present invention relates to a martensitic free cutting stainless steel, comprising: by weight percent, C: 0.10 to 1.20%, Si: 0.10 to 2.00%, Mn: 0.80 to 2.00%, S: 0.10 to 0.30%, Cr: 10.5 to 18.0%, Pb: 0.03 to 0.30%, Te: 0.01 to 0.10%, B: 0.0005 to 0.010%, and O: 0.005 to 0.030%, with the reminder being substantially Fe and inevitable impurities; wherein, among the inevitable impurities, contents of P and N are, P: 0.005 to 0.10%, and N: ?0.050%; wherein respective formulae of 3.0?[Mn]/[S]?15.0, 0.10?[Te]/[S], and 10?[S]/[O]?40 are satisfied; and wherein a sulfide having a circle equivalent diameter of 2.0 ?m or more and an aspect ratio of 10 or less is present in a total amount of 0.50 to 10% by area ratio.
    Type: Application
    Filed: October 2, 2007
    Publication date: April 17, 2008
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Koichi ISHIKAWA, Tetsuya SHIMIZU
  • Publication number: 20080055031
    Abstract: The present invention relates to a process of producing a permanent magnet, which includes extruding a preform to form a plate-shaped permanent magnet, in which the preform is extruded in such a way that a dimension of a cross section of the preform is reduced in an X-direction and enlarged in a Y-direction perpendicular to the X-direction. The present invention also relates to a plate-shaped permanent magnet formed by extruding a preform, in which the preform is extruded in such a way that a dimension of a cross section of the preform is reduced in an X-direction and enlarged in a Y-direction perpendicular to the X-direction, whereby the permanent magnet has a strain ratio ?2/?1 with respect to the preform in a range of 0.2 to 3.5, in which ?1 is a strain in the direction of the extrusion of the preform and ?2 is a strain in the Y-direction.
    Type: Application
    Filed: August 31, 2007
    Publication date: March 6, 2008
    Applicant: DAIDO TOKUSHUKO KABUSHIKI KAISHA
    Inventors: Junichi Esaki, Hiroaki Yoshida, Sachihiro Isogawa