Patents Assigned to Nippon Koshuha Steel Co., Ltd.
  • Patent number: 10829841
    Abstract: This hot work tool steel has a composition containing C: 0.45 to 0.57 mass %, Si: 0.05 to 0.30 mass %, Mn: 0.45 to 1.00 mass %, Cr: 4.5 to 5.2 mass %, Ni: 0.5 mass % or less, Mo+(½) W: 1.0 to 2.0 mass %, V: 0.30 to 0.80 mass %, and N: 0.008 to 0.025 mass %, the remainder being Fe and unavoidable impurities, and the area ratio of carbide having an equivalent circle diameter of 1 ?m or less being 20% or higher. It is thereby possible to improve thermal conductivity to thereby shorten cycle time, and improving hardness after heat treatment to improve abrasion resistance while sufficient hardenability is maintained. Consequently, it is possible to obtain a hot work tool steel having excellent toughness with high hardness, excellent corrosion resistance, and minimal degradation of machinability.
    Type: Grant
    Filed: January 6, 2015
    Date of Patent: November 10, 2020
    Assignee: NIPPON KOSHUHA STEEL CO., LTD.
    Inventors: Tsuyoshi Tonomura, Kentaro Suzuki
  • Patent number: 9991438
    Abstract: The present invention provides a magnetostrictive member with high performance, high reliability and high versatility. The magnetostrictive member is used in the vibration power generation as a power source for extracting electric energy from various vibrations. The member made of the single crystal is manufactured cheaper than the conventional manufacturing method. The magnetostrictive member is formed by cutting a single crystal of Fe—Ga alloy by using electric discharge machining in a state that <100> orientation of the crystal of the Fe—Ga alloy is aligned in a direction in which magnetostriction of the magnetostrictive member is required.
    Type: Grant
    Filed: July 14, 2017
    Date of Patent: June 5, 2018
    Assignee: NIPPON KOSHUHA STEEL Co., Ltd
    Inventor: Katsuya Imai
  • Patent number: 9902093
    Abstract: A press-forming mold has a protective film for preventing seizing during press-forming formed on at least a forming surface that comes into contact with a formed body. The protective film is formed by PVD. An arbitrary selection section extracted from the surface of the protective film is divided into a plurality of individual sections; and, when the gradient of the surface at the nth division point is represented by (dZn/dXn), taking N to represent the number of divisions, the root-mean-square R?q calculated by the following numerical expression is no greater than 0.032. R ? ? ? ? ? q = 1 N ? ? n = 1 N ? ? ( d ? ? Z n d ? ? X n ) 2 It is thereby possible to improve the seizing resistance of a press-forming mold having a protective film formed by PVD.
    Type: Grant
    Filed: April 3, 2012
    Date of Patent: February 27, 2018
    Assignees: NIPPON KOSHUHA STEEL CO., LTD., KOBE STEEL, LTD.
    Inventors: Takaharu Kashi, Kenji Yamamoto
  • Patent number: 9017830
    Abstract: The present invention provides a shearing die having longer life and a method for manufacturing the same. The shearing die includes a pair of substrates, at least one of which has a hard film formed by an arc ion plating method and located at least on a region of a curved surface and on an adjacent region from the end part of the curved surface on the side facing to the surface of the sheet or plate material to 300 ?m along the surface of the substrate. The hard film comprises Al and one or more of Ti and Cr, and has a thickness of 1 to 5 ?m, such that a number of metal particles having a diameter of 20 ?m or more, which are present on a line segment having a length of 10 mm on a surface of the hard film, is 2 or less.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: April 28, 2015
    Assignees: Kobe Steel, Ltd., Nippon Koshuha Steel Co., Ltd.
    Inventors: Kenji Yamamoto, Yasuhiro Hayashida, Junji Yoshida
  • Publication number: 20110314991
    Abstract: The present invention provides a shearing die having longer life and a method for manufacturing the same.
    Type: Application
    Filed: June 28, 2011
    Publication date: December 29, 2011
    Applicants: Nippon Koshuha Steel Co., Ltd., Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Kenji YAMAMOTO, Yasuhiro Hayashida, Junji Yoshida
  • Publication number: 20100132429
    Abstract: The present invention provides a cold-work die steel useful as a material of dies for cold pressing, which has basic properties such as hardness, toughness and dimensional change by heat treatment, and besides, which causes no problem in terms of machined surface roughness and cutting tool life, and also its dies for cold pressing. The invention relates to a cold-work die steel comprising: 0.5 to 0.7 mass % of C; 5.0 to 7.0 mass % of Cr; 0.5 to 2.0 mass % of Si; 0.1 to 2.0 mass % of Mn; 0.001 to 0.010 mass % of Al; 0.25 to 1.00 mass % of Cu; 0.25 to 1.00 mass % of Ni; 0.5 to 3.0 mass % of Mo+0.5×W; 0.5 mass % or less of V; 0.05 mass % or less of P; 0.1 mass % or less of S; 0.005 mass % or less of O, wherein the following requirements are satisfied: [C]×[Cr]?4; FP=[Si]/5+[Cr]/5+2×[Mo]+[W]+2×[V]+10×[Al]?5.0; and AP=[Mn]+3×([Cu]+[Ni])?2.5, and also relates to a die for cold pressing which is manufactured by using the cold-work die steel.
    Type: Application
    Filed: January 7, 2009
    Publication date: June 3, 2010
    Applicants: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel Ltd), Nippon Koshuha Steel Co. Ltd.
    Inventors: Shogo Murakami, Tsuyoshi Tonomura
  • Publication number: 20100135844
    Abstract: The present invention relates to a cold-work die steel, comprising by mass %: 0.5 to 0.7% of C; 0.5 to 2.0% of Si; 0.1 to 2.0% of Mn; 5 to 7% of Cr; 0.01 to 1.0% of Al; 0.003 to 0.025% of N; 0.25 to 1% of Cu; 0.25 to 1% of Ni; 0.5 to 3% of Mo; 2% or less (including 0%) of W; and 0.1% or less (excluding 0%) of S, with a remainder being iron and an unavoidable impurity; wherein the following requirements (1) to (3) are satisfied: (1) [Cr]×[C]?4; (2) [Al]/[N]: 1 to 30; and (3) [Mo]+0.5×[W]: 0.5 to 3.00%, wherein the bracket means a content (%) of an element written therein.
    Type: Application
    Filed: September 18, 2008
    Publication date: June 3, 2010
    Applicants: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel,Ltd.), Nippon Koshuha Steel Co., Ltd.
    Inventors: Shogo Murakami, Shigenobu Namba, Kenji Yamamoto, Tsuyoshi Tonomura
  • Publication number: 20100074792
    Abstract: The invention relates to a cold work die steel containing, by mass %, C: 0.20 to 0.60%, Si: 0.5 to 2.00%, Mn: 0.1 to 2%, Cr: 3.00 to 9.00%, Al: 0.3 to 2.0%, Cu: 1.00 to 5%, Ni: 1.00 to 5%, Mo: 0.5 to 3% and/or W: 2% or less (including 0%), S: 0.10% or less (not including 0%), in which the following requirements (1) to (3) are satisfied {wherein each square bracket [ ] means a content (%) of each element}: [Cr]×[C]?3.00,??(1) [Cu]/[Ni]:0.5 to 2.2,??(2) [Mo]+0.5×[W]:0.5 to 3.0%,??(3) with the remainder being iron and unavoidable impurities; and to a die obtained by the using the same. The invention also relates to a production method for a cold work die steel.
    Type: Application
    Filed: October 16, 2007
    Publication date: March 25, 2010
    Applicants: KABUSHIKI KAISHA KOBE SEIKO SHO (KOBE STEEL, LTD.), NIPPON KOSHUHA STEEL CO., LTD.
    Inventors: Shogo Murakami, Tsuyoshi Tonomura
  • Patent number: 6060018
    Abstract: Cold tool steel having superior machinability, wear-resistance and minimized heat treatment size-change were obtained by specifying components and contents thereof, especially of C, Cr, Si, V and Mo, not by high-temperature soaking. Further, such prehardened cold tool steals as having excellent machinability even after heat-treatment together with minimum size-change were manufactured by further strictly specifying components, particularly of C, Si, Mn, Mo, V, and by specifying heat-treatment conditions.
    Type: Grant
    Filed: September 11, 1998
    Date of Patent: May 9, 2000
    Assignee: Nippon Koshuha Steel Co., Ltd.
    Inventors: Junji Yoshida, Yuji Machida, Keiichi Hayashida, Masaaki Otakane
  • Patent number: 5732512
    Abstract: A manhole opening structure having a cover traveling rail on which at least one manhole cover can travel between a manhole opening and the ground and rail lifter serving to upwardly and downwardly move the cover traveling rail between a lower position where the manhole cover closes the manhole opening and an upper position where the manhole cover can move between the cover traveling rail and the ground.
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: March 31, 1998
    Assignees: Nippon Koshuha Steel Co., Ltd., Koshuha Foundry Co., Ltd.
    Inventors: Takashi Ueno, Tsutomu Taneichi
  • Patent number: 5630538
    Abstract: The machine consists of a bearing box which is secured onto the trunk of the machine and is equipped with a pair of axes at both sides and suspends the center of gravity of the machine to rotate same freely, and a U-type supporting device is installed at the axes respectively, and a revolving or swivel joint is installed at the upper end of the above supporting device so as to enable the machine to rotate freely.
    Type: Grant
    Filed: January 3, 1995
    Date of Patent: May 20, 1997
    Assignees: Nippon Koshuha Steel Co., Ltd., Koshuha Foundry Co. Ltd
    Inventors: Akiyoshi Hatakeyama, Isamu Takemoto
  • Patent number: 5628218
    Abstract: This flaw-treatment apparatus is able to prevent an increase in the number of flaw cuts by detecting false flaw-detection, and prevent the occurrence of die marks. For attaining these effects, this apparatus is comprised of: detection of the surface flaws of the wire-shaped metal by applying a flaw-detecting device, cutting and removal of the detected flaws by applying a flaw-cutting device, drawing of the flaw-free wire-shaped metal by applying a drawing device, spraying of lubricant on the wire-shaped metal, and removal of excess lubricant together with dust, and further grinding of the flaw-cut portion of the wire-shaped metal for obtaining adequate surface roughness before grinding.
    Type: Grant
    Filed: September 15, 1994
    Date of Patent: May 13, 1997
    Assignee: Nippon Koshuha Steel Co., Ltd.
    Inventors: Akinobu Yamada, Toshiyuki Furutani, Norihiro Oda
  • Patent number: 5582051
    Abstract: This flaw-removal device prevents overlooking of flaws in the automatic flaw-cutting process by rectifying the twist of a wire-shaped metal drawn from a cannon-shaped wire supply stand, further promoting efficiency in removing remaining flaws by applying the automatic flaw-cutting process and removing the uncut flaws by hand. In this invention, a twist-rectifying drum 3 is installed in front of a flaw-detecting device 4. It then becomes possible to rectify the twisting of the wire-shaped metal by winding the wire-shaped metal installed on a cannon-shaped wire supply stand around the twist-rectifying drum in a length longer than one turn of the coiled wire-shaped metal so that the wire-shaped metal is freely mounted on the drum. It also becomes possible to remove an uncut flaw by hand by installing a flaw-check and removal site 10 having a specified span between drawing dies 8 and a wire-drawing drum 9, and by stopping the portion of the wire-shaped metal having uncut flaws at the site 10.
    Type: Grant
    Filed: September 14, 1994
    Date of Patent: December 10, 1996
    Assignee: Nippon Koshuha Steel Co., Ltd.
    Inventors: Yoshiteru Ishikawa, Toshihiro Kidani
  • Patent number: 5458703
    Abstract: A tool steel production method and a tool steel are disclosed in this invention. The method consists of following two steps:1. Toughness (Ch) of the tool steel is evaluated from a formula:Ch=f(Vp, H, T)after estimating Vp, a square sum of output voltage of total Barkhausen noise signals which are produced in the process of magnetization of the tool steel sample, and measuring temperring hardness (H) and hardening temperature (T) of the tool steel sample.2. A tool steel having a required toughness is produced by adjusting temperring hardness (H) and/or hardening temperature (T) based on the toughness evaluation of the tool steel sample mentioned above.
    Type: Grant
    Filed: August 24, 1993
    Date of Patent: October 17, 1995
    Assignee: Nippon Koshuha Steel Co., Ltd.
    Inventor: Norihiko Nakai
  • Patent number: 4911885
    Abstract: a high carbon chromium bearing steel having a carbon content from 0.8% to 1.2% by weight, and which is characterized by a nickel content of 1.0% to 2.0% by weight, a chromium content of 0.9% to 2.0% by weight, a silicon content of 1.0% to 2.0% by weight, and a sulfur combined and phosphorus content of 0.015% to 0.040% by weight.
    Type: Grant
    Filed: March 31, 1989
    Date of Patent: March 27, 1990
    Assignees: Koyo Seiko Co., Ltd., Nippon Koshuha Steel Co., Ltd.
    Inventors: Yoshiaki Hyodo, Masamichi Shibata, Toshihiro Miyakawa
  • Patent number: 4312210
    Abstract: A method for warm forging a cup-shaped piece is disclosed. In warm forging a blank is heated between 400.degree. and 800.degree. C. and is inserted within a die having a cross sectional area substantially larger than that of the blank. The ends of the blank are clamped between a recess in the die and a recess in an upsetting punch and the upsetting punch compresses the blank until its sides become sufficiently bulged to almost touch, or touch, the sides of the die. The upsetting punch is then removed and a backward extruding punch is press fitted into the bulged blank and the blank is extruded to form a cup. The extrusion punch is lubricated and cooled by lubricant and coolant applicators at a position remote from the die so that the blank is not prematurely cooled by the coolant.
    Type: Grant
    Filed: March 14, 1980
    Date of Patent: January 26, 1982
    Assignees: Kobe Steel Limited, Nippon Koshuha Steel Co. Ltd.
    Inventors: Masatoshi Nishizawa, Toshihiro Minami, Takeshi Nakahara, Toyofumi Hasegawa
  • Patent number: 4291600
    Abstract: Process and apparatus for cutting surface flaws of a material to be machined, including detecting the travelling speed and position of a wire material or a rod-like material in order to set a cut-in quantity to be applied to a cutting tool on the basis of a flaw-depth signal of the signals so detected, operating the advancing and retreating timings of the cutting tool on the basis of the travelling speed signal, the flaw the surface flaw position signal and a tool cut-in angle set value signal that is set in advance, operating simultaneously the advancing and retreating speeds of the cutting tool on the basis of the travelling speed signal and the cut-in angle set value signal and actuating and controlling a tool driving device in accordance with the results of these operations.
    Type: Grant
    Filed: February 6, 1979
    Date of Patent: September 29, 1981
    Assignees: Kobe Steel, Limited, Nippon Koshuha Steel Co., Ltd.
    Inventors: Yosiyuki Kawaguchi, Takashi Nishida, Nobuaki Marukawa, Tadakazu Tanaka, Yoshinari Kontani