Spring Or Spring Material Patents (Class 148/580)
  • Patent number: 10836013
    Abstract: A coil spring includes a helically formed wire having end turn portions at ends thereof, a plurality of first rough surfaces, each including first shot peening indentations formed on a part of a surface of the end turn portions, and a second rough surface including second shot peening indentations formed on the entire surface of the wire except for the first rough surface. The second rough surface has a surface roughness different from that of the first rough surface.
    Type: Grant
    Filed: April 12, 2019
    Date of Patent: November 17, 2020
    Assignee: NHK SPRING CO., LTD.
    Inventors: Senri Moriyama, Satoshi Akiyama, Masaya Komazaki, Go Nagayasu, Hideki Okada, Daisuke Yokota
  • Patent number: 10357926
    Abstract: Provided are a metal/CFRP composite structure which has lightweight and high strength by combining hot-pressed metal material(s) and carbon fiber reinforced plastic (CFRP) material(s), and its manufacturing method and apparatus. A metal blank material is heated to a temperature at which quenching is possible to obtain a first intermediate product quenched by hot-pressing. The first intermediate product, and a carbon fiber reinforced plastic (CFRP) prepreg comprising carbon fiber and uncured thermoset plastic are set into CFRP forming dies followed by press-forming the prepreg to obtain a secondary intermediate product having the CFRP in intimate contact with a surface of the first intermediate product. The CFRP and the first intermediate product are firmly adhered together by thermal curing of thermoset plastic located in the boundary of the CFRP and the first intermediate product, by subjecting the thermoset plastic contained in the CFRP prepreg to thermal curing.
    Type: Grant
    Filed: November 18, 2013
    Date of Patent: July 23, 2019
    Assignee: AISIN TAKAOKA CO., LTD.
    Inventors: Kiyohito Kondo, Yuji Yamashita
  • Patent number: 10309004
    Abstract: A method for treating sheet metal is disclosed in which a material containing at least one alloying element is applied onto a first area of at least one surface of the metal sheet. A second area of the surface is kept free of the material. The metal sheet is subsequently heat treated in order to diffuse the alloying element into the first area of the metal sheet. The temperature of the first area is lower than the melting temperature of the metal sheet during the diffusion.
    Type: Grant
    Filed: July 17, 2015
    Date of Patent: June 4, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Hartmut Baumgart, Ronald Sanders
  • Patent number: 9815108
    Abstract: A radial compression mechanism includes a plurality of die, each of the plurality of die have a wedge shaped tip. The dies are arranged around a common central axis so that the wedge shaped tips form an elongated central cavity and move between an expanded position and a contracted position. Each die includes a fluid duct extending lengthwise through the die proximate the wedge-shaped tip. Each fluid duct includes an inlet fluid port and an outlet fluid port. The fluid ducts are connected in parallel by a fluid supply manifold connected to each inlet fluid port of each die by an inlet conduit, and a fluid return manifold connected to each outlet fluid port of each die by an outlet conduit.
    Type: Grant
    Filed: June 10, 2016
    Date of Patent: November 14, 2017
    Inventor: Tom Hyde
  • Patent number: 9546682
    Abstract: A cage of a rolling bearing, the cage comprising: an annular heel centered on a central axis and having a constant radial thickness measured radially to the central axis; an axial portion extending from the heel substantially parallel to the central axis; and pockets delimited by the heel and the axial portion for receiving rolling elements. The axial portion has an axial length being greater than half the inner diameter of the pockets and an outside diameter being lesser than the outside diameter of the heel and which comprises between a first value equal to the pitch circle diameter of the cage minus half the radial thickness of the heel and a second value equal to the pitch circle diameter of the cage plus half the radial thickness of the heel. The pockets are spaced around the central axis having angular spacings being at least partly different from one another.
    Type: Grant
    Filed: December 9, 2014
    Date of Patent: January 17, 2017
    Assignee: AKTIEBOLAGET SKF
    Inventors: Lawrence E Cislo, Riccardo Restivo, Thierry Poulle
  • Patent number: 9336688
    Abstract: A tactile display includes a base; movable pins having free ends for tactile sensing by a user, the pins arranged in rows and columns and movable between an extended position and retracted position with respect to the base so as to selectively display tactilely sensible data; a resilient element for supporting each pin in the extended position when at rest, and further operative to urge the pin from the retracted position to the extended position in the presence of an opposing force; one or more reset elements for lowering the pins from the extended position to the retracted position; row stoppers for lockably engaging rows of pins when in the second position.
    Type: Grant
    Filed: March 4, 2012
    Date of Patent: May 10, 2016
    Assignee: TACTILE WORLD LTD.
    Inventors: Igor Karasin, Gavriel Karasin
  • Patent number: 9091315
    Abstract: The invention relates to a wave spring (2) which comprises a spring strip (4) which is coiled in a substantially circular-ring-shaped manner and, over the circumference, describes a wavy line which oscillates about a radial reference plane and has wave crests (6) and wave troughs. The ends of the circular-ring-shaped spring strip (4) are connected by means of a weld seam (10) which is arranged in a low-tension region of the wavy line of the spring strip (4) between a wave crest (6) and an adjacent wave trough (8).
    Type: Grant
    Filed: February 1, 2012
    Date of Patent: July 28, 2015
    Assignee: Scherdel Innotec Forschungs—Und Entwicklungs—GmbH
    Inventor: Peter Doetterl
  • Patent number: 9062364
    Abstract: A method for producing a carbonitrided member comprising the steps of carburizing a steel part having a composition of, by mass percent, C: 0.10 to 0.35%, Si: 0.15 to 1.0%, Mn: 0.30 to 1.0%, Cr: 0.40 to 2.0%, S: 0.05% or less with the balance being Fe and impurities in a carburizing atmosphere of 900 to 950° C. The carburized steel part is carbonitrided in a carbonitriding atmosphere with the temperature of 800 to 900° C. and the nitrogen potential of 0.2 to 0.6%. The carbonitrided steel part is qhenched and then shot peened. The shot peening treatment may be further performed while heating to a temperature not higher than 350° C. or immediately after heating to a temperature not higher than 350° C. After quenching, the shot peening treatment may be further performed after tempering in the temperature range exceeding 250° C. and not higher than 350° C.
    Type: Grant
    Filed: March 8, 2012
    Date of Patent: June 23, 2015
    Assignees: NIPPON STEEL & SUMITOMO METAL CORPORATION, HONDA MOTOR CO., LTD.
    Inventors: Naoyuki Sano, Masayuki Horimoto, Yoshinari Okada, Masaki Amano, Akihito Ninomiya
  • Publication number: 20150101715
    Abstract: A steel wire for spring is provided which exhibits high strength even without adding a large amount of alloy elements, and is for obtaining a cold winding spring having excellent coiling performance and improved hydrogen embrittlement resistance. The steel wire for spring is characterized in that C: 0.40-0.65% (mass %), Si: 1.0-3.0%, Mn: 0.6-2.0%, P: 0.015% or less (exclusive of 0%), S: 0.015% or less (exclusive of 0%), and Al: 0.015 percent by mass or less (excluding 0%) of S, and Al: 0.001-0.10% are satisfied, with the remainder consisting of iron and inevitable impurities, tempered martensite: 70 area % or more and retained austenite: 6-15 area % with respect to the total microstructure, the prior austenite grain size number obtained by a method stipulated in JIS G 0551 is No. 10.0 or more, and the tensile strength is 1,900 MPa or more.
    Type: Application
    Filed: May 20, 2013
    Publication date: April 16, 2015
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Atsuhiko Takeda, Nao Yoshihara
  • Patent number: 9005378
    Abstract: Disclosed is a spring steel wire rod that comprises C in a range of 0.35 to 0.65% (mass %, the same applies to respective elements described hereinafter), Si in a range of 1.4 to 2.2%, Mn in a range of 0.10 to 1.0%, Cr in a range of 0.1 to 2.0%, P not more than 0.025% (0% excluded), and S not more than 0.025% (0% excluded), balance comprising iron, and unavoidable impurities, wherein an average grain size Dc of a central part of the steel wire rod is not more than 80 ?m while an average grain size Ds of a surface layer part of the steel wire rod is not less than 3.0 ?m.
    Type: Grant
    Filed: August 15, 2008
    Date of Patent: April 14, 2015
    Assignee: Kobe Steel, Ltd.
    Inventors: Takuya Kochi, Shogo Murakami, Takeshi Kuroda, Hiromichi Tsuchiya
  • Publication number: 20150091225
    Abstract: Leaf springs, and methods of manufacturing thereof, having first and second sections, spaced apart along the length of said leaf spring, said sections are through hardened and tempered to achieve, respectively different levels of finished through hardness, are disclosed.
    Type: Application
    Filed: September 29, 2014
    Publication date: April 2, 2015
    Inventors: William Wilson, Brian Farrell
  • Publication number: 20140306389
    Abstract: A compression coil spring having high durability can be provided by using an inexpensive wire material. The present invention provides a compression coil spring formed by using a steel wire material, the steel wire material made of C: 0.45 to 0.85 mass %, Si: 0.15 to 2.5 mass %, Mn: 0.3 to 1.0 mass %, Fe and inevitable impurities as a remainder, and a circle-equivalent diameter of 1.5 to 9.0 mm, wherein hardness of a freely selected cross-section of the wire material is 570 to 700 HV, and at an inner diameter side of the coil spring, unloaded compressive residual stress at a depth of 0.2 mm from a surface in an approximate maximal main stress direction in a case in which compressive load is loaded on the spring is 200 MPa or more, and unloaded compressive residual stress at a depth of 0.4 mm from surface is 100 MPa or more.
    Type: Application
    Filed: July 26, 2012
    Publication date: October 16, 2014
    Applicant: NHK SPRING CO., LTD.
    Inventors: Kazuya Ikai, Tohru Shiraishi, Yuichiro Ono, Yoshiki Ono
  • Patent number: 8789817
    Abstract: A high-strength spring steel and a spring are provided that have superior corrosion fatigue strength. The spring steel comprises, in mass percent, 0.35-0.55% C, 1.60-3.00% Si, 0.20-1.50% Mn, 0.10-1.50% Cr, and at least one of 0.40-3.00% Ni, 0.05-0.50% Mo and 0.05-0.50% V, the balance being substantially Fe and incidental elements and impurities.
    Type: Grant
    Filed: September 28, 2010
    Date of Patent: July 29, 2014
    Assignee: Chuo Hatsujo Kabushiki Kaisha
    Inventors: Takanori Kuno, Tomohiro Nakano, Takayuki Sakakibara, Masami Wakita, Shingo Mimura
  • Patent number: 8734599
    Abstract: Provided is a steel wire rod for a high strength and high toughness spring having excellent cold workability, the steel wire rod having a composition comprising: in weight %, C: 0.4 to 0.7%, Si: 1.5 to 3.5%, Mn: 0.3 to 1.0%, Cr: 0.01 to 1.5%, Ni: 0.01 to 1.0%, Cu: 0.01 to 1.0%, B: 0.005 to 0.02%, Al: 0.1% or less, O: 0.0020% or less, P: 0.02% or less, S: 0.02% or less, N: 0.02% or less, remainder Fe, and other unavoidable impurities, having a microstructure formed of ferrite and pearlite, and in which a prior (before cooling) austenite grain size is 8 ?m or less.
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: May 27, 2014
    Assignee: Posco
    Inventors: Sang Woo Choi, Hoe Young Jung, Yong Tae Shin, Duk Lak Lee, Jeong Do Seo, Jay Hyung Jung, Byoung Ju Park, Jae Seung Lee
  • Publication number: 20140060709
    Abstract: Steel, excellent in corrosion resistance and low-temperature toughness, for a vehicle suspension spring part, includes 0.15 to 0.35% by mass of C, more than 0.6% by mass but 1.5% by mass or less of Si, 1 to 3% by mass of Mn, 0.3 to 0.8% by mass of Cr, 0.005 to 0.080% by mass of sol. Al, 0.005 to 0.060% by mass of Ti, 0.005 to 0.060% by mass of Nb, not more than 150 ppm of N, not more than 0.035% by mass of P, not more than 0.035% by mass of S, 0.01 to 1.00% by mass of Cu, and 0.01 to 1.00% by mass of Ni, the balance consisting of Fe and unavoidable impurities, with Ti+Nb?0.07% by mass. The steel has a tensile strength of not less than 1,300 MPa.
    Type: Application
    Filed: November 11, 2013
    Publication date: March 6, 2014
    Applicants: JFE BARS & SHAPES CORPORATION, NHK SPRING CO., LTD.
    Inventors: Akira TANGE, Kiyoshi KURIMOTO, Yurika GOTO, Katsuhiko KIKUCHI, Kunikazu TOMITA, Kazuaki FUKUOKA, Kazuaki HATTORI
  • Patent number: 8608874
    Abstract: Disclosed is high strength spring steel that can limit the depth of pitting occurring when corroded and therefore possesses high strength as well as excellent pitting corrosion resistance and corrosion fatigue property, with a composition containing: C: greater than 0.35 mass % and less than 0.50 mass %; Si: greater than L75 mass % and less than or equal to 3.00 mass %; Mn: 0.2 mass % to 1.0 mass %; Cr: 0.01 mass % to 0.04 mass %; P: 0.025 mass % or less; S: 0.025 mass % or less; Mo: 0.1 mass % to 1.0 mass %; and 0: 0.0015 mass % or less, under a condition that a PC value calculated by PC=4.2×([C]+[Mn])+0.1×(1/[Si]+1/[Mo])+20.3×[Cr]+0.001×(1/[N]) is greater than 3.3 and equal to or less than 8.0. Also disclosed is a preferred method for manufacturing the same.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: December 17, 2013
    Assignee: JFE Steel Corporation
    Inventors: Minoru Honjo, Kazukuni Hase, Hideto Kimura
  • Patent number: 8533954
    Abstract: A spring wire with a hardness of 50 to 56 HRC is subjected to first and second shot peening processes within a warm working temperature range of 150° C. to 350° C. In the first shot peening process, a first shot of a shot size of at least 1.0 mm is used. In the second shot peening process, a second shot smaller in shot size than the first shot is used. Through these shot peening processes, compressive residual stress is imparted to the spring wire. The spring wire includes a residual stress increase part, residual stress peak part, and residual stress decrease part. In the residual stress decrease part, a part including a compressive residual stress magnitude equivalent to the magnitude of the compressive residual stress at a surface of the spring wire exists at a region at a depth exceeding the permissible pit depth.
    Type: Grant
    Filed: August 10, 2011
    Date of Patent: September 17, 2013
    Assignee: NHK Spring Co., Ltd.
    Inventors: Akira Tange, Hideki Okada, Isao Sumiyoshi, Mitsuhiro Sugiyama
  • Patent number: 8506732
    Abstract: Apparatus and method are provided for metallurgical heat treatment of coil springs, or similarly shaped workpieces and articles of manufacture, by electric resistance heating along the entire length of the workpiece so that the ends of the workpiece can be heat treated to the same degree and quality as the section of the workpiece between its two ends.
    Type: Grant
    Filed: August 3, 2010
    Date of Patent: August 13, 2013
    Assignee: Radyne Corporation
    Inventor: Jerry G. Warner
  • Patent number: 8470104
    Abstract: A method of manufacturing a high strength valve spring for a vehicle engine is provided, which includes (a) forming a high strength wire rod in the form of a spring using a roller type jig, (b) cutting an end of the formed spring using a rotary type cutting blade, (c) performing residual stress removal heat treatment at 390° C. to 410° C. for 20 to 40 minutes, (d) performing shot peening for applying compression stress to a surface of the spring with fine ball particles, and (e) performing hot setting for applying, in advance, plastic deformation to the spring. Accordingly, the damage of the spring during the spring forming process is prevented, and the hardness deterioration of the spring during the residual stress removal heat treatment process is also prevented.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: June 25, 2013
    Assignees: Hyundai Motor Company, Kia Motors Corporation
    Inventor: Jung Suk Lee
  • Patent number: 8470105
    Abstract: A high carbon steel wire material which is made of high carbon steel as a raw material for wire products such as steel cords, bead wires, PC steel wires and spring steel, allows for these wire products to be manufactured efficiently at a high wire drawing rate and has excellent wire drawability and a manufacturing process thereof. This high carbon steel wire material is made of a steel material having specific contents of C, Si, Mn, P, S, N, Al and O, and the Bcc-Fe crystal grains of its metal structure have an average crystal grain diameter (Dave) of 20 ?m or less and a maximum crystal grain diameter (Dmax) of 120 ?m or less, preferably an area ratio of crystal grains having a diameter of 80 ?m or more of 40% or less, an average sub grain diameter (dave) of 10 ?m or less, a maximum sub grain diameter (dmax) of 50 ?m or less and a (Dave/dave) ratio of the average crystal grain diameter (Dave) to the average sub grain diameter (dave) of 4.5 or less.
    Type: Grant
    Filed: May 15, 2009
    Date of Patent: June 25, 2013
    Assignee: Kobe Steele, Ltd.
    Inventors: Takuya Kochi, Shogo Murakami, Hiroshi Yaguchi, Takeshi Kuroda, Hidenori Sakai, Tomotada Maruo, Takaaki Minamida
  • Patent number: 8460483
    Abstract: A method for heat treatment of a coiled spring includes cold forming a coiled spring, annealing the coiled spring after the cold forming, thereby removing of residual stress generated in the cold forming, in which the annealing is performed by electric resistance heating.
    Type: Grant
    Filed: March 21, 2011
    Date of Patent: June 11, 2013
    Assignee: NHK Spring Co., Ltd.
    Inventors: Takashi Yajima, Hideki Okada, Katsuyuki Nishioka, Takeshi Furuse
  • Publication number: 20130127100
    Abstract: Provided are: a steel wire rod material for a high-strength spring, which does not undergo the increase in deformation resistance arising from the increase in hardness and can exhibit good wire-drawing processability and the like even when a heat treatment, which deteriorates productivity, is eliminated or a simplified and rapid heat treatment is employed instead; a useful method for producing the steel wire rod material for a high-strength spring; a high-strength spring produced using the steel wire rod material for a high-strength spring as a material; and others. This steel wire rod material for a high-strength spring is a steel wire rod material that has been hot-rolled already, and has a texture having a specified chemical composition and mainly composed of pearlite, wherein the average value (Pave) of the pearlite nodule size numbers and the standard deviation (P?) of the pearlite nodule size numbers fulfill the following formulae (1) and (2), respectively: 9.5?Pave?12.0;??(1) and 0.2?P??0.
    Type: Application
    Filed: August 30, 2011
    Publication date: May 23, 2013
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Tomonobu Ishida, Nao Yoshihara, Shuhei Kitamura
  • Publication number: 20130118655
    Abstract: A spring consists of, by mass %, 0.5 to 0.7% of C, 1.0 to 2.0% of Si, 0.1 to 1.0% of Mn, 0.1 to 1.0% of Cr, not more than 0.035% of P, not more than 0.035% of S, and the balance of Fe and inevitable impurities. The spring has a structure including not less than 65% of bainite and 4 to 13% of residual austenite by area ratio in a cross section. The spring has a compressive residual stress layer in a cross section from a surface to a depth of 0.35 mm to D/4, in which D (mm) is a circle-equivalent diameter of the cross section. The spring has a high hardness layer with greater hardness than a center portion by 50 to 500 HV from a surface to a depth of 0.05 to 0.3 mm.
    Type: Application
    Filed: August 4, 2011
    Publication date: May 16, 2013
    Applicant: NHK SPRING CO., LTD.
    Inventors: Takeshi Suzuki, Yoshiki Ono, Shimpei Kurokawa, Kosuke Shibairi
  • Publication number: 20130048158
    Abstract: Disclosed is high strength spring steel that can limit the depth of pitting occurring when corroded and therefore possesses high strength as well as excellent pitting corrosion resistance and corrosion fatigue property, with a composition containing: C: greater than 0.35 mass % and less than 0.50 mass %; Si: greater than L75 mass % and less than or equal to 3.00 mass %; Mn: 0.2 mass % to 1.0 mass %; Cr: 0.01 mass % to 0.04 mass %; P: 0.025 mass % or less; S: 0.025 mass % or less; Mo: 0.1 mass % to 1.0 mass %; and 0: 0.0015 mass % or less, under a condition that a PC value calculated by PC=4.2×([C]+[Mn])+0.1×(1/[Si]+1/[Mo])+20.3×[Cr]+0.001×(1/[N]) is greater than 3.3 and equal to or less than 8.0. Also disclosed is a preferred method for manufacturing the same.
    Type: Application
    Filed: February 28, 2011
    Publication date: February 28, 2013
    Applicant: JFE STEEL CORPORATION
    Inventors: Minoru Honjo, Kazukuni Hase, Hideto Kimura
  • Patent number: 8382918
    Abstract: The steel wire material for a spring of the invention contains; C: 0.37-0.54%, Si: 1.7-2.30%, Mn: 0.1-1.30%, Cr: 0.15-1.1%, Cu: 0.15-0.6%, Ti: 0.010-0.1%, Al: 0.003-0.05%, and the balance including iron with inevitable impurities, wherein ferrite decarburized layer depth is 0.01 mm or less, whole decarburized layer depth is 0.20 mm or less, and fracture reduction of area is 25% or more. It alternately may contain; C: 0.38-0.47%, Si: 1.9-2.5%, Mn: 0.6-1.3%, Ti: 0.05-0.15%, Al: 0.003-0.1%, and the balance including iron with inevitable impurities, wherein ferrite decarburized layer depth is 0.01 mm or less.
    Type: Grant
    Filed: June 29, 2011
    Date of Patent: February 26, 2013
    Assignee: Kobe Steel, Ltd.
    Inventors: Nao Yoshihara, Fujio Koizumi, Hirokazu Inoue, Katsuya Takaoka, Shoji Miyazaki, Sayaka Nagamatsu
  • Publication number: 20120291927
    Abstract: Drawn heat treated steel wire for high strength spring use is provided containing, by mass %, C: 0.67% to less than 0.9%, Si: 2.0 to 3.5%, Mn: 0.5 to 1.2%, Cr: 1.3 to 2.5%, N: 0.003 to 0.007%, and Al: 0.0005% to 0.003%, having Si and Cr satisfying the following formula: 0.3%?Si?Cr?1.2%, and having a balance of iron and unavoidable impurities, having as impurities, P: 0.025% or less and S: 0.025% or less, furthermore having a circle equivalent diameter of undissolved spherical carbides of less than 0.2 ?m, further having, as a metal structure, at least residual austenite in a volume rate of over 6% to 15%, having a prior austenite grain size number of #10 or more, and having a circle equivalent diameter of undissolved spherical carbides of less than 0.2 ?m.
    Type: Application
    Filed: July 5, 2011
    Publication date: November 22, 2012
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Masayuki Hashimura, Tetsushi Chida
  • Publication number: 20120285585
    Abstract: A spring steel contains 0.15-0.40% carbon, 1-3.5% silicon, 0.20-2.0% manganese, 0.05-1.20% chromium, at most 0.030% phosphorus, at most 0.02% sulfur, and at least one of the following: 0.005-0.10% titanium, 0.005-0.05% niobium, and at most 0.25% vanadium. The remainder of said spring steel includes iron and unavoidable impurities. The carbon equivalent (Ceq1) of the provided spring steel, as calculated by formula (1), is at most 0.55. (1) Ceq1=[C]+0.108×[Si]?0.067×[Mn]+0.024×[Cr]?0.05×[Ni]+0.074×[V]. In the formula (1), each symbol in brackets represents the content (mass %) of the corresponding element.
    Type: Application
    Filed: December 21, 2010
    Publication date: November 15, 2012
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Sayaka Nagamatsu, Tomotada Maruo, Nao Yoshihara
  • Publication number: 20110303327
    Abstract: The steel wire material for a spring of the invention contains; C: 0.37-0.54%, Si: 1.7-2.30%, Mn: 0.1-1.30%, Cr: 0.15-1.1%, Cu: 0.15-0.6%, Ti: 0.010-0.1%, Al: 0.003-0.05%, and the balance including iron with inevitable impurities, wherein ferrite decarburized layer depth is 0.01 mm or less, whole decarburized layer depth is 0.20 mm or less, and fracture reduction of area is 25% or more. It alternately may contain; C: 0.38-0.47%, Si: 1.9-2.5%, Mn: 0.6-1.3%, Ti: 0.05-0.15%, Al: 0.003-0.1%, and the balance including iron with inevitable impurities, wherein ferrite decarburized layer depth is 0.01 mm or less, Ceq1 in the equation (1) below is 0.580 or more, Ceq2 in the equation (2) below is 0.49 or less, and Ceq3 in the equation (3) below is 0.570 or less. Ceq1=[C]+0.11[Si]?0.07[Mn]?0.05[Ni]+0.02[Cr]??(1) Ceq2=[C]+0.30[Cr]?0.15[Ni]?0.70[Cu]??(2) Ceq3=[C]?0.04[Si]+0.24[Mn]+0.10[Ni]+0.20[Cr]?0.89[Ti]?1.92[Nb]??(3) (In the above equations, [ ] shows the content (mass %) of each element in steel.
    Type: Application
    Filed: June 29, 2011
    Publication date: December 15, 2011
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Nao YOSHIHARA, Fujio Koizumi, Hirokazu Inoue, Katsuya Takaoka, Shoji Miyazaki, Sayaka Nagamatsu
  • Patent number: 8043444
    Abstract: A steel wire for a cold-formed spring according to the present invention contains a prescribed chemical component composition, wherein: a martensitic transformation start temperature MS1 shown by the following expression (1) is in the range from 280° C. to 380° C.; the austenite grain size number N of austenite grains is No. 12 or more; the grain boundary share of carbide precipitated along the austenite grain boundaries is 50% or less; the amount of retained austenite after austenitized and tempered is 20 vol. % or less; and the tensile strength is 2,000 MPa or more; MS1=550?361[C]?39[Mn]?20[Cr]??(1), where [C], [Mn] and [Cr] represent the contents (mass %) of C, Mn and Cr, respectively. Such a steel wire can: secure hot-rolling formability and subsequent drawability while aiming at higher strength and higher stress; moreover exhibit excellent corrosion resistance; and obtain a spring (mainly a suspension spring for an automobile) excellent also in fatigue strength which is a basic required characteristic.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: October 25, 2011
    Assignee: Kobe Steel, Ltd.
    Inventor: Nao Yoshihara
  • Patent number: 8038934
    Abstract: A spring steel having a high strength of 1900 MPa or more and superior in the brittle fracture resistance, as well as a method for manufacturing the same, are provided. The high strength spring steel comprises, as basic components in mass %, C: 0.4-0.6%, Si: 1.4-3.0%, Mn: 0.1-1.0%, Cr: 0.2-2.5%, P: 0.025% or less, S: 0.025% or less, N: 0.006% or less, Al: 0.1% or less, and O: 0.003% or less, the amount of solute C being 0.15% or less, the amount of Cr contained as a Cr-containing precipitate being 0.10% or less, and a TS value represented by the following equation being 24.8% or more, and in point of structure, the pre-austenite grain diameter being 10 ?m or smaller, wherein TS=28.5*[C]+4.9*[Si]+0.5*[Mn]+2.5*[Cr]+1.7*[V]+3.7*[Mo] where [X] stands for mass % of element X.
    Type: Grant
    Filed: January 23, 2007
    Date of Patent: October 18, 2011
    Assignee: Kobe Steel, Ltd.
    Inventors: Takuya Kochi, Hiroshi Yaguchi, Wataru Urushihara
  • Publication number: 20110232810
    Abstract: A method for heat treatment of a coiled spring includes cold forming a coiled spring, annealing the coiled spring after the cold forming, thereby removing of residual stress generated in the cold forming, in which the annealing is performed by electric resistance heating.
    Type: Application
    Filed: March 21, 2011
    Publication date: September 29, 2011
    Applicant: NHK SPRING CO., LTD.
    Inventors: Takashi YAJIMA, Hideki OKADA, Katsuyuki NISHIOKA, Takeshi FURUSE
  • Patent number: 8007602
    Abstract: Spring element, in particular spring rail for wipers, in particular of motor vehicles, with a low tendency to vibrate or a high attenuation, made from a ferritic chromium steel comprising 0.03 to 0.12% of carbon, 0.2 to 0.9% of silicon, 0.3 to 1% of manganese, 13 to 20% of chromium, 0.1 to 2.0% of molybdenum, 0.05 to 1.0% of copper, 0.02 to 0.05% of nitrogen, less than 0.01% of titanium, 0.01 to 0.10% of niobium and 0.02 to 0.25% of vanadium, remainder iron.
    Type: Grant
    Filed: February 4, 2010
    Date of Patent: August 30, 2011
    Assignee: Stahlwerk Ergste Westig GmbH
    Inventors: Oskar Pacher, Gisbert Kloss-Ulitzka, Victor Castro
  • Patent number: 8007606
    Abstract: An improved method for salvaging a spring element with a degraded force constant for return to a work environment. The spring element is subjected to a high temperature and extended duration annealing treatment alone or in combination with other treatments. The resultant salvaged spring is characterized by a more durable force constant relative to the original spring when it was new.
    Type: Grant
    Filed: June 25, 2008
    Date of Patent: August 30, 2011
    Assignee: Caterpillar Inc.
    Inventors: Sami El-Sayed, Howard D. Jenkel, Paul May
  • Publication number: 20110074079
    Abstract: A manufacturing method of a coil spring for an automobile suspension includes forming a material into a coil shape; performing a heat treatment step on the material; performing a warm shot peening step on the material, and performing a hot setting step on the material. By performing the warm shot peening step prior to the hot setting step, a stronger compressive residual stress is imparted in a direction along which a large tensile stress acts during actual use of the coil spring, thereby improving sag resistance and durability of the coil spring. A coil spring is also manufactured according to this method.
    Type: Application
    Filed: September 28, 2010
    Publication date: March 31, 2011
    Applicant: CHUO HATSUJO KABUSHIKI KAISHA
    Inventors: Tomohiro Nakano, Takayuki Sakakibara, Takanori Kuno, Shingo Mimura, Masami Wakita
  • Patent number: 7901520
    Abstract: Disclosed herein is a spring wire rod excelling in fatigue characteristics. It contains TiN inclusions having a specific size defined by the ratio of each group in all the visual fields as follows: (1) Visual fields in which the maximum thickness is no larger than 5 ?m: less than 5% (2) Visual fields in which the maximum thickness is larger than 5 ?m and no larger than 10 ?m: no more than 30% (3) Visual fields in which the maximum thickness is larger than 10 ?m and no larger than 25 ?m: no less than 70% (4) Visual fields in which the maximum thickness is larger than 25 ?m: less than 5% The visual field is the cross section passing through the center line of the wire rod.
    Type: Grant
    Filed: June 26, 2008
    Date of Patent: March 8, 2011
    Assignee: Kobe Steel, Ltd.
    Inventor: Nao Yoshihara
  • Patent number: 7828917
    Abstract: A rail manufacturing method is provided, in which a billet is hot-rolled into a rail form and the rail is cooled to ambient temperature. The foot part of the rail can be mechanically restrained to improve the straightness of the rail during at least the period of cooling where the surface temperature is between 800° C. and 400° C. In the subsequent cooling process, at least while the surface temperature of the foot of the rail is between 400° C. and 250° C., the rail is kept in an upright state, and cooled naturally without using insulation or accelerated cooling.
    Type: Grant
    Filed: January 7, 2005
    Date of Patent: November 9, 2010
    Assignee: Nippon Steel Corporation
    Inventors: Noriaki Onodera, Takuya Satoh, Masaharu Ueda, Kazuo Fujita, Akira Kobayashi
  • Patent number: 7699943
    Abstract: The present invention intends to provide a method for manufacturing a high-strength spring, which is capable of generating a higher level of compressive residual stress than that given by conventional methods. This object is achieved as follows: After the final heating process, such as the tempering (in the case of a heat-treated spring) or removing-strain annealing (in the case of a cold-formed spring), a shot peening process is performed on the spring while the surface temperature of the spring is within the range from 265 to 340° C. (preferably from 300 to 340° C.). Subsequently, the spring is rapidly cooled. Preferably, a prestressing process is performed before the shot peening process, or after the shot peening process and before the rapid cooling process. The rapid cooling process may be either a water-cooling process or an oil-cooling process. A forced-air cooling process may be used if the wire diameter of the spring is small.
    Type: Grant
    Filed: March 24, 2004
    Date of Patent: April 20, 2010
    Assignee: Chuo Hatsujo Kabushiki Kaisha
    Inventors: Tomohiro Nakano, Takayuki Sakakibara, Masami Wakita
  • Publication number: 20090320970
    Abstract: An improved method for salvaging a spring element with a degraded force constant for return to a work environment. The spring element is subjected to a high temperature and extended duration annealing treatment alone or in combination with other treatments. The resultant salvaged spring is characterized by a more durable force constant relative to the original spring when it was new.
    Type: Application
    Filed: June 25, 2008
    Publication date: December 31, 2009
    Applicant: Caterpillar Inc.
    Inventors: Sami El-Sayed, Howard D. Jenkel, Paul May
  • Patent number: 7597768
    Abstract: Disclosed is a hard-drawn spring which exhibits fatigue strength and sag resistance equal or superior to springs produced using an oil-tempered wire. The hard-drawn spring is produced using a steel wire containing 0.5 to 0.7 mass % of C, 1.0 to 1.95 mass % of Si, 0.5 to 1.5 mass % of Mn and 0.5 to 1.5 mass % of Cr, with the balance being Fe and inevitable impurities. In the steel wire, the number of carbides having circle-equivalent diameters of 0.1 ?m or more is 5 particles/100 ?m2 or less.
    Type: Grant
    Filed: March 26, 2003
    Date of Patent: October 6, 2009
    Assignees: Kabushiki Kaisha Kobe Seiko Sho, Suncall Corporation
    Inventors: Sumie Suda, Nobuhiko Ibaraki, Nao Yoshihara, Shigetsugu Yoshida, Koji Harada
  • Publication number: 20090174129
    Abstract: Provided is a high-strength stainless steel spring exhibiting a good workability and having a high load characteristic. Thus, the high-strength stainless steel spring of the invention has an chemical component containing 0.04 to 0.08% by mass of C, 0.15 to 0.22% by mass of N, 0.3 to 2.0% by mass of Si, 0.5 to 3.0% by mass of Mn, 16 to 20% by mass of Cr, 8.0 to 10.5% by mass of Ni, 0.5 to 3.0% by mass of Mo, and the balance of Fe and inevitable impurities, and when the average diameter of the coil is represented by D and further the diameter of the steel wire is represented by d in the case that cross sections of the stainless steel wire are in a complete round form or the value obtained by subtracting the average coil diameter from the outer diameter of the coil is represented by d? in the case that the cross sections of the stainless steel wire are in a form other than the complete round form, the spring has a spring index D/d or D/d? of 2 to 6.
    Type: Application
    Filed: February 16, 2007
    Publication date: July 9, 2009
    Applicants: SUMITOMO ELECTRIC INDUSTRIES, LTD., SUMITOMO (SEI) STEEL WIRE CORP., NHK SPRING CO., LTD.
    Inventors: Hiromu Izumida, Nozomu Kawabe, Shinei Takamura, Teruyuki Murai, Noritoshi Takamura
  • Publication number: 20090139615
    Abstract: The present invention provides a leaf spring material superior in mechanical characteristics and a manufacturing method of the leaf spring material capable of reliably achieving the same, utilizing induction hardening. The manufacturing method of the leaf spring material comprises the steps of imparting tensile stress on a first surface along the longitudinal direction of the first surface and compressive stress on a second surface along the longitudinal direction of the second surface of a substantially strip-shaped steel plate, and subjecting the first surface to induction hardening. With this induction hardening, an induction-hardened structure having a higher average hardness than that of a parent material structure in the vicinity of the second surface and comprising martensite and finely and evenly dispersed austenite is imparted on a surface layer in the vicinity of the first surface.
    Type: Application
    Filed: November 26, 2008
    Publication date: June 4, 2009
    Applicants: NHK SPRING CO., LTD, HORIKIRI, INC.
    Inventors: Michihiko Ayada, Yoshiki Ono, Fumio Takahashi, Hironori Ebashi, Sakae Kikuchi
  • Publication number: 20090065105
    Abstract: Disclosed is a spring steel wire rod that comprises C in a range of 0.35 to 0.65% (mass %, the same applies to respective elements described hereinafter), Si in a range of 1.4 to 2.2%, Mn in a range of 0.10 to 1.0%, Cr in a range of 0.1 to 2.0%, P not more than 0.025% % excluded), and S not more than 0.025% (0% excluded), balance comprising iron, and unavoidable impurities, wherein an average grain size Dc of a central part of the steel wire rod is not more than 80 ?tm while an average grain size Ds of a surface layer part of the steel wire rod is not less than 3.0 ?m.
    Type: Application
    Filed: August 15, 2008
    Publication date: March 12, 2009
    Applicant: KABUSHIKI KAISHA KOBE SEIKO SHO (Kobe Steel, Ltd)
    Inventors: Takuya Kochi, Shogo Murakami, Takeshi Kuroda, Hiromichi Tsuchiya
  • Publication number: 20090020195
    Abstract: The present invention provides high strength spring and high strength spring steel wire superior in corrosion fatigue characteristics and methods of production of the same, that is, a high strength spring steel wire and high strength spring containing, by mass %, C: 0.35 to 0.50%, Si: 1.00 to 3.00%, and Mn: 0.10 to 2.00%, restricting P to 0.015% or less and S to 0.015% or less, having a balance of Fe and unavoidable impurities, and, when raising the temperature in the range from 50° C. to 600° C. by 0.25° C./s and measuring the differential scanning calories, having the only peak of the exothermic reaction present at 450° C. or more. A method of production of high strength spring characterized by tempering under conditions where the tempering temperature T[K], tempering time t[s], and content Si % [mass %] of Si satisfy the following: 16000?(T?40×[Si %])×(31.7+log t)?23000.
    Type: Application
    Filed: January 7, 2008
    Publication date: January 22, 2009
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Manabu Kubota, Masayuki Hashimura
  • Publication number: 20090020189
    Abstract: The steel wire material for a spring of the invention contains; C: 0.37-0.54%, Si: 1.7-2.30%, Mn: 0.1-1.30%, Cr: 0.15-1.1%, Cu: 0.15-0.6%, Ti: 0.010-0.1%, Al: 0.003-0.05%, and the balance including iron with inevitable impurities, wherein ferrite decarburized layer depth is 0.01 mm or less, whole decarburized layer depth is 0.20 mm or less, and fracture reduction of area is 25% or more. It alternately may contain; C: 0.38-0.47%, Si: 1.9-2.5%, Mn: 0.6-1.3%, Ti: 0.05-0.15%, Al: 0.003-0.1%, and the balance including iron with inevitable impurities, wherein ferrite decarburized layer depth is 0.01 mm or less, Ceq1 in the equation (1) below is 0.580 or more, Ceq2 in the equation (2) below is 0.49 or less, and Ceq3 in the equation (3) below is 0.570 or less. Ceq1=[C]+0.11[Si]?0.07[Mn]?0.05[Ni]+0.02[Cr]??(1) Ceq2=[C]+0.30[Cr]?0.15[Ni]?0.70[Cu]??(2) Ceq3=[C]?0.04[Si]+0.24[Mn]+0.10[Ni]+0.20[Cr]?0.89[Ti]?1.92[Nb]??(3) (In the above equations, [ ] shows the content (mass %) of each element in steel.
    Type: Application
    Filed: July 11, 2008
    Publication date: January 22, 2009
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Nao YOSHIHARA, Fujio Koizumi, Hirokazu Inoue, Katsuya Takaoka, Shoji Miyazaki, Sayaka Nagamatsu
  • Patent number: 7459037
    Abstract: A method of surface-treating a reactor member for effectively removing a Cr-deficient layer and a work-hardened layer considered to be a cause of stress corrosion cracking (SCC) under low-stress conditions. The method of surface-treating a reactor member which is worked by bending (step 1) and then processed by a heat treatment (step 2), in which a work-hardened layer is formed by the bending, and in which a Cr-deficient layer is formed due to an oxide film attached by the heat treatment, uses at least one of: acid wash; grinding; electrolytic polishing; electro-discharge machining; surface cutting; surface deoxidation and softening; wet blasting; laser machining; or surface plating (step 3) to remove the work-hardened layer and the Cr-deficient layer from the reactor member or to prevent contact of the work-hardened layer and the Cr-deficient layer of the reactor member with a primary coolant.
    Type: Grant
    Filed: January 25, 2005
    Date of Patent: December 2, 2008
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Kazuki Monaka, Juntaro Shimizu, Yoichiro Yamaguchi
  • Patent number: 7407555
    Abstract: An oil-tempered wire for a cold-formed coil spring having a quality equivalent of or higher than a hot-formed coil spring is provided. A cold-formed coil spring made from the oil-tempered wire is also provided. Material used is the steel which contains, in weight percentage, 0.35 to 0.55% C, 1.8 to 3.0% Si, 0.5 to 1.5% Mn, 0.5 to 3.0% Ni, and 0.1 to 1.5% Cr. The ferrite fraction in the microscopic structure of this material is set to 50% or less. Hot rolled wire is cold drawn with a predetermined reduction of area, and a heat treatment using high frequency induction heating is conducted. It is preferable to set the maximum heating temperature between 900° C. to 1020° C. (favorably 950° C.) and holding time between 5 to 20 seconds. It is preferable to make the oil tempered material to have the grain size number of 9 or more, and the tensile strength from 1830 to 1980 MPa.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: August 5, 2008
    Assignee: Chuo Hatsujo Kabushiki Kaisha
    Inventors: Hidetoshi Yoshikawa, Tomohiro Nakano, Takayuki Sakakibara, Masami Wakita
  • Patent number: 7404865
    Abstract: A high-strength steel wire for heat-resistant springs has both excellent high-temperature tensile strength and excellent high-temperature sag resistance at a temperature as high as 350 to 500° C., particularly at 400° C. or so (these properties are needed for spring materials). The steel wire contains (a) 0.01 to 0.08 wt % C, 0.18 to 0.25 wt % N, 0.5 to 4.0 wt % Mn, 16 to 20 wt % Cr, and 8.0 to 10.5 wt % Ni, (b) at least one constituent selected from the group consisting of 0.1 to 3.0 wt % Mo, 0.1 to 2.0 wt % Nb, 0.1 to 2.0 wt % Ti and 0.3 to 2.0 wt % Si, and (c) mainly Fe and unavoidable impurities both of which constitute the remainder. The steel wire has (a) a tensile strength of at least 1,300 N/mm2 and less than 2,000 N/mm2 before being treated with low-temperature annealing, and (b) a maximum crystal-grain diameter of less than 12 ?m in the ? phase (austenite) in a transverse cross section of the wire.
    Type: Grant
    Filed: January 24, 2002
    Date of Patent: July 29, 2008
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Hiromu Izumida, Nozomu Kawabe, Teruyuki Murai
  • Patent number: 7284308
    Abstract: Leaf springs have improved durability in spite of using inexpensive spring steel such as SUP9 and SUP11 as materials. While a spring main body, made of the spring steel in which Brinell hardness is under 555 HBW and not less than 388 HBW (corresponding to a diameter of under 2.70 mm of hardness and not less than 3.10mm of hardness on a Brinell ball mark), is maintained at 150 to 400° C., the load is applied in the direction in which the spring main body is to be used, and the first shotpeening is performed at the plane where the tensile stress acts.
    Type: Grant
    Filed: November 29, 2002
    Date of Patent: October 23, 2007
    Assignee: NHK Spring Co., Ltd.
    Inventors: Mamoru Akeda, Junichi Yano, Isamu Okuyama, Akira Tange
  • Patent number: 7255758
    Abstract: A steel wire of pearlite structure containing 0.8-1.0 mass % of C and 0.8-1.5 mass % of Si is disclosed. In the cross section of the steel wire the difference in average hardness between a region up to 100 ?m from the surface thereof and a deeper region is within 50 in micro-Vickers hardness. The steel wire is manufactured by working a wire rod having the abovementioned chemical composition through shaving, patenting and drawing processes, then strain-relief annealing the resultant wire, and thereafter subjecting the thus annealed to a shot peening process. The steel wire has a high heat resistance and a high fatigue strength, and can be produced through a drawing process without applying a quenching and tempering process.
    Type: Grant
    Filed: February 11, 2003
    Date of Patent: August 14, 2007
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Nozomu Kawabe, Teruyuki Murai, Koji Yamaguchi, Yukihiro Oishi
  • Publication number: 20070137741
    Abstract: Disclosed is a cold formable spring steel wire excellent in cold cutting capability and fatigue properties, in which the steel wire satisfies given composition, has an average globular carbide particle size [?(ab)]:1.0 ?m or less with aspect ratio (a/b, a: major axis of carbide, b: minor axis of carbide) being 2 or less, a ratio (area %) of the globular carbide in the steel: (0.1 to 3)×amount (mass %) of C in the steel, an amount (mass %) of Cr in the globular carbide: [0.4×amount (mass %) of Cr in the steel] or less, hardenability factor (Dic): between 110 mm and 450 mm, and tensile stress of 2000 MPa or more.
    Type: Application
    Filed: November 14, 2006
    Publication date: June 21, 2007
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventor: Nao Yoshihara