Induction Patents (Class 148/567)
  • Publication number: 20080128057
    Abstract: A process of induction-heating helical springs, more particularly valve springs, for the purpose of carrying out subsequent hardening by quenching and tempering, wherein the helical springs, while being individually fixed and rotatingly driven, are guided through an electro-magnetic alternating field.
    Type: Application
    Filed: October 31, 2007
    Publication date: June 5, 2008
    Inventors: Thorsten Hufnagel, Rudolf Bonse
  • Patent number: 7306684
    Abstract: Quenched layers are formed without irregularities on the inner circumferential surface of a track bushing having a small inside diameter or on the inner circumferential surfaces of two or more track bushings which are subjected to quenching in an overlapped condition. To introduce a cooling medium for cooling the inner circumferential surface of the track bushing, a guide tube having an outside diameter smaller than the inside diameter of the track bushing is disposed on the side of the inner circumferential surface and the cooling medium introduced by the guide tube is diverted by a diverting member having a spherical or similar curved surface, such that the cooling medium is allowed to flow in a direction substantially parallel with an axial direction of the track bushing 1 within a space defined by the outer circumferential surface of the guide tube and the inner circumferential surface of the track bushing, thereby performing laminar flow cooling.
    Type: Grant
    Filed: June 7, 2001
    Date of Patent: December 11, 2007
    Assignee: Komatsu Ltd
    Inventors: Takemori Takayama, Chigo Okayama, Masayuki Ohishi, Takeyo Terao
  • Patent number: 7220327
    Abstract: Disclosed is a material of a kick-down drum comprising fine ferrite and microdispersion spheroidized cementite for an automobile also disclosed is a method for manufacturing the kick-down drum material. The kick-down drum of this invention can greatly improve hardenability and durability of the spline member and also has advantages of reducing production costs due to a simplified process of adding only a heating process.
    Type: Grant
    Filed: December 1, 2004
    Date of Patent: May 22, 2007
    Assignee: Hyundai Motor Company
    Inventors: Ji Hong Yoo, Doo Hwan Lee
  • Patent number: 7162798
    Abstract: Selective laser and induction hardening are applied to areas of a water jacketed engine cylinder liner to provide improved resistance to scuffing resulting from the rubbing contact of the walls and piston rings of an associated piston. An upper bore portion and port relief areas of the liner are fully induction hardened to improve wear resistance. The port area is then fully laser hardened to improve wear resistance. If desired, the laser hardening process may continue beyond the intake port area to the port relief areas to ensure full hardening of the port relief areas and continuous hardening between the intake ports and the port relief areas to improve wear resistance.
    Type: Grant
    Filed: February 26, 2004
    Date of Patent: January 16, 2007
    Assignee: Electro-Motive Diesel, Inc.
    Inventor: Mitchell K. Westra
  • Patent number: 7161124
    Abstract: An apparatus and method for altering characteristics, such as can include structural, magnetic, electrical, optical or acoustical characteristics, of an electrically-conductive workpiece utilizes a magnetic field within which the workpiece is positionable and schemes for thermally treating the workpiece by heating or cooling techniques in conjunction with the generated magnetic field so that the characteristics of the workpiece are effected by both the generated magnetic field and the thermal treatment of the workpiece.
    Type: Grant
    Filed: April 19, 2005
    Date of Patent: January 9, 2007
    Assignee: UT-Battelle, LLC
    Inventors: Roger A. Kisner, John B. Wilgen, Gerard M. Ludtka, Roger A. Jaramillo, Gail Mackiewicz-Ludtka
  • Patent number: 7147729
    Abstract: A method and apparatus are provided in accordance with embodiments of the present invention for heat-treating electrical contacts. The method and apparatus include plating a core wire with at least one conductive coating to form an electrical contact that experiences internal stresses. The method and apparatus further include induction heating the electrical contact for a predetermined period of time to at least partially relieve the internal stresses. A plurality of electrical contacts may be mounted on a substrate that is held near induction coils to cause heating. The electrical contacts may be formed with spring shaped bodies that are aligned at a desired orientation within magnetic fields created during induction heating. In accordance with at least one embodiment of the present invention, different portions of each electrical contact may be annealed by different desired amounts.
    Type: Grant
    Filed: February 11, 2002
    Date of Patent: December 12, 2006
    Assignee: Tyco Electronics Corporation
    Inventors: George Jyh-Shann Chou, Bogdan Octav Ciocirlan
  • Patent number: 7145115
    Abstract: An apparatus for hardening cylindrical bearing locations on a shaft, in particular a crankshaft, in which transition radii to the adjacent shaft parts are of undercut design, is provided with a heating unit, which is connected to a power supply, and with an inductor. The inductor has two heating conductor arms, which are arranged at a distance from one another and each run in the peripheral direction of the bearing location that is to be hardened. Each of the two heating conductor arms is provided with an inner bearing-surface hardening branch and two outer radius hardening branches, the bearing-surface hardening branch in each case being mechanically connected to the radius hardening branches by current-carrying elements which bear the radius hardening branches. The mechanical connection is sufficiently elastic for the radius hardening branches to be displaceable relative to the bearing-surface hardening branch in the axial direction of the shaft that is to be hardened.
    Type: Grant
    Filed: August 6, 2004
    Date of Patent: December 5, 2006
    Assignee: Maschinenfabrik Alfing Kessler GmbH
    Inventors: Andreas Zahn, Ralph Gerbeth
  • Patent number: 7037383
    Abstract: A process for producing a component of metal includes a) carrying out a heat treatment to harden the component, which ends with a heating process, especially with a tempering or microstructural transformation process, at a given temperature (TE); b) carrying out at least machining of the component at room temperature (TU) in order to provide its desired geometrical shape; and c) subsequent heating of the component to a temperature (T) which is greater than room temperature (TU).
    Type: Grant
    Filed: February 25, 2003
    Date of Patent: May 2, 2006
    Assignee: AB SKF
    Inventor: Jürgen Gegner
  • Patent number: 6963057
    Abstract: Multiple workpieces are inductively heated by passing them through one or more induction heating coils. Passage of a section of each workpiece through a coil may oscillate in the forward and reverse directions, independent of the movement of the other workpieces, one or more times, to selectively heat each workpiece while operating the power supplies for each of the induction heating coils at constant current, voltage and/or power to maximize the efficiency of the electrical circuit and minimize the requirements for power supply control circuitry.
    Type: Grant
    Filed: April 18, 2003
    Date of Patent: November 8, 2005
    Assignee: Inductotherm Corp.
    Inventors: Wallace Shane Swanger, Edward J. Rylicki, Oleg S. Fishman
  • Patent number: 6918224
    Abstract: A method of forming a vehicle component, particularly an elongated impact beam, having an open section structure, in a manner to provide predetermined strategically strengthened portions, comprising the steps of cold forming unhardened steel into a workpiece having mounting surfaces, selectively fixturing the mounting surfaces, static induction heating the workpiece with lengthwise surface eddy currents on selected portions, followed by quenching of the fixtured heated workpiece to form strengthened portions, and unfixturing the resulting component. Also disclosed is apparatus to accomplish this, and the resulting novel vehicle component.
    Type: Grant
    Filed: May 1, 2002
    Date of Patent: July 19, 2005
    Assignee: Benteler Automotive Corporation
    Inventors: Todd W. J. Tjoelker, John D. Bowman, Alessandro Libriani, Joseph C. Kollaritsch
  • Patent number: 6884975
    Abstract: A system and method inductively heats and stress relieves a weld joint area having a stress induced zone. A susceptor assembly is positioned over the stress induced zone. The susceptor assembly includes susceptor sheets manufactured to operate at different, preselected Curie temperatures. A housing is mounted over the susceptor assembly including an induction coil positioned adjacent to the susceptor assembly. An alternating electric current is applied to the induction coil. The alternating electric current causes the induction coil to generate a plurality of magnetic flux lines. The invention provides the advantage that the magnetic flux lines passing through the susceptor assembly heat the susceptor assembly providing localized and controlled temperature heat to the weld joint area to stress relieve the stress induced zone.
    Type: Grant
    Filed: November 12, 2002
    Date of Patent: April 26, 2005
    Assignee: The Boeing Company
    Inventors: Marc R. Matsen, Terry L. Smith
  • Patent number: 6855217
    Abstract: The present invention relates to a method of baking treatment of steel product parts using a high frequency or ultra-high frequency for preventing delayed fracture from occurring due to diffusive hydrogen occluded in steel parts, for example, screws, bolts and the like, or for heating surface layers of the steel parts to generate a difference in temperature between the surface layers and interiors of the steel parts, thereby causing distortion in lattices, wherein the surface layers of the steel parts are rapidly heated to 100 to 300° C. with a high frequency or ultra-high frequency at 10 KHz or higher to remove the diffusive hydrogen which is involved in hydrogen embrittlement, or to transfer an existing state to non-diffusive hydrogen which is not involved in the hydrogen embrittlement.
    Type: Grant
    Filed: October 21, 2002
    Date of Patent: February 15, 2005
    Assignee: Aoyama Seisakusho Co., Ltd.
    Inventor: Takamasa Suzuki
  • Patent number: 6843866
    Abstract: Process for the effective production of very wear-resistant layers in the thickness range of 0.2 to approx. 3 mm by way of inductively supported surface layer modification. It can be used particularly advantageously for the protection of components of hardenable steels and cast iron with abrasive, corrosive, high-temperature corrosive or mineral sliding wear loading. With the process according to the invention a local two-stage inductive short-time preheating takes place directly before the surface layer coating. Due to the invention it is possible to coat even hardenable steels or other materials difficult to coat without cracking. Furthermore, even harder coating materials susceptible to cracking which provide better wear-resistances can be used. In addition, process speeds and surface coating performances can be achieved that are higher by a factor of 10 compared with conventional laser build-up welding.
    Type: Grant
    Filed: August 1, 2002
    Date of Patent: January 18, 2005
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung e.V.
    Inventors: Berndt Brenner, Volker Fux
  • Patent number: 6811622
    Abstract: The invention relates to semifinished and finished products made from special corrosion-resistant precipitation-hardened austenitic steel containing a large amount of intersticially dissolved nitrogen, comprising substantially smooth surfaces. The invention also relates to a method for producing corresponding semifinished and finished items. The aim of the invention is to produce semifinished and finished item and to provide an economical method for the production thereof, combining both solidity and resistance to corrosion. This is achieved by precipitation-hardening areas of the steel material.
    Type: Grant
    Filed: June 26, 2002
    Date of Patent: November 2, 2004
    Inventors: Heinrich Friederich, Reinhard Schmoock
  • Publication number: 20040211497
    Abstract: A drive pulley for elevators, with at least two sectors, wherein at least one sector is hardened and at least one sector is not hardened.
    Type: Application
    Filed: April 20, 2004
    Publication date: October 28, 2004
    Applicant: Inventio AG
    Inventors: Urs Ammon, Hanspeter Bloch
  • Patent number: 6797084
    Abstract: An apparatus for manufacturing a case hardened journal cross includes an inductor having an open side to allow the journal cross to be inserted and withdrawn from the induction process with relative ease. The conductive frame of the inductor is shaped in a cross-like pattern that outlines the outer perimeter of a journal cross on each side of the journal cross. Because the induction coil passes across both sides of the journal cross, heat treating may be enhanced at specific locations of the outer surface of the journal cross by adjusting the distance of the induction coil from the journal cross. Also, a method for manufacturing such a journal cross includes determining the maximum stress distribution for the journal cross and, based thereon, determining the desired depth and location of the case hardening.
    Type: Grant
    Filed: June 20, 2002
    Date of Patent: September 28, 2004
    Assignee: Dana Corporation
    Inventors: Mark Shuster, Donald A. Rhoda, Glen Fillion, Otto Zaslavskiy
  • Publication number: 20040154705
    Abstract: A fixing element which comprises carbon-bearing steel and has a hardened functional tip is overall heated to the austenitisation temperature, held at that temperature and then quenched and is then subjected to an annealing operation which is effected by inductive heating and limited to the region of the fixing element, which lies outside the functional tip. In that way the structure of the fixing element comprises in part martensite and in part annealed martensite, wherein the functional tip comprises throughout martensite and the remainder of the fixing element comprises a martensite which is annealed by short-term inductive heating.
    Type: Application
    Filed: December 15, 2003
    Publication date: August 12, 2004
    Inventors: Heinrich Friederich, Reinhard Schmoock
  • Patent number: 6765181
    Abstract: An apparatus and process are provided for induction heat treatment of electrically conductive workpieces. The inductor assembly is formed from a single piece inductor that utilizes an electrically non-conductive top, side and bottom frames to hold flux concentrators in place over the sides of the inductor. Flux concentrators can be changed by unfastening the frame members, removing the existing flux concentrators, inserting new flux concentrators, and fastening the frame members. One or more of the frame members may serve as a receiving chamber for supply of a quench medium to an induction heated workpiece positioned in an opening in the inductor.
    Type: Grant
    Filed: September 16, 2003
    Date of Patent: July 20, 2004
    Assignee: Inductoheat, Inc.
    Inventors: Madhu S. Chatterjee, Byron L. Taylor, Micah Robert Black
  • Publication number: 20040016478
    Abstract: An apparatus for rolling of a powder metallurgical metallic workpiece is provided having a feeding device, a first induction heating apparatus in operable communication with a first RF generator and at least a first hot rolling mill. A process control device monitors at least one parameter of the first RF generator and outputs a signal. A method for continuous rolling of a metallic workpiece is also provided using the apparatus for rolling. The process control device signal can be used to monitor metallurgical properties of the workpiece and provide in-line evaluation of the workpiece.
    Type: Application
    Filed: July 25, 2002
    Publication date: January 29, 2004
    Inventors: David Sharpe, Firooz Rasouli, John F. Cunningham
  • Patent number: 6677561
    Abstract: The invention relates to a coil to be used in transverse flux induction heating of an object in the form of a metal strip or another elongate metal workpiece. The coil contains at least one pair of loops of conductors, which are non-symmetrically positioned to each other and the conductors overlap each other so that the inductor has double conductors across the object to be heated and a single conductor parallel to the object to be heated at the edges. The heating effect is prevented alone in the conductors by dividing the induced current for the conductors to two equal branches each having the same width as the original current and the combined heating effect in the branches is only half of the heating effect before branching.
    Type: Grant
    Filed: October 21, 2002
    Date of Patent: January 13, 2004
    Assignee: Outokumpu Oyj
    Inventors: Ilpo Koppinen, Brian Swank
  • Publication number: 20030230366
    Abstract: A method of thermomechanically forming an aluminide part of a workpiece resistively heats at least a portion of the aluminide part, plastically deforms the heated portion of the aluminide part to a predetermined shape by applying pressure to the aluminide part positioned in a shaping member, and cools the aluminide part while applying pressure to maintain the aluminide part in the predetermined shape. The shaping member is movably mounted on a support base and a source of electricity provides an electrical current passing through the aluminide part for resistive heating of the part. The aluminide part can be a heater blade array for an electrical heater cigarette smoking system.
    Type: Application
    Filed: June 13, 2002
    Publication date: December 18, 2003
    Inventors: John M. Adams, Naohisa Tsukamura
  • Patent number: 6635856
    Abstract: A plurality of billets are inductively heated in a staged process wherein the output current of a power supply is repeatedly time shared among a plurality of induction coils within which the plurality of billets have been placed. The time periods of the applied current to each coil become sequentially shorter over the total heating time of a billet to allow magnetically induced heat to conduct to the center of the billet during the dwell periods between applied electrical current periods. This maximizes the efficiency of the output of the power supply while melting of the outer regions of a billet is avoided in a process wherein the billets do not have to be moved during the overall billet total heating time.
    Type: Grant
    Filed: January 17, 2003
    Date of Patent: October 21, 2003
    Assignee: Inductotherm Corp.
    Inventor: Oleg S. Fishman
  • Publication number: 20030178110
    Abstract: The invention relates to a production method for producing, on a production installation (1), flat products, also of a large width, from continuously cast slabs having a large or medium thickness or from thin slabs. Said production installation is comprised of a single or multiple stand blooming train (4), of a roller table (3), which is provided for conveying the rolling stock and, optionally for oscillating, of a roller table section (5) with hinged heat-insulating covering hoods. The production installation is also comprised of a straightening unit (6) for straightening the pre-strips, of an, in particular, inductive heating installation (7) for effecting the controlled heating of the pre-strips to a defined temperature over the length and width of the pre-strips, of a multiple-stand finishing train (10), of a delivery roller table with devices (11) for cooling the hot rolled strip, and of subsequently arranged coiling machines (12) for coiling the finished strip.
    Type: Application
    Filed: May 23, 2003
    Publication date: September 25, 2003
    Inventors: Harald Wehage, Ulrich Skoda-Dopp, Michael Breuer, Joachim Hafer
  • Patent number: 6576877
    Abstract: A method for induction heating a workpiece made of a material such as ferrous material or alloy is carried out by placing a non-magnetic conductive shield in proximity to a current concentrating surface of the workpiece and exposing the workpiece with a shield in place to a time varying magnetic field. The magnetic field induces eddy currents in the surface of the workpiece. The conductive shield is placed in sufficient proximity to reduce or eliminate the eddy currents in the portion covered by the shield. At least a part of the uncovered portion of the workpiece is heated above the austenitizing or solution temperature of the material. At the same time, the covered portions of the workpiece are protected from overheating by the shield. The workpiece is then quenched to complete the hardening process.
    Type: Grant
    Filed: September 14, 2001
    Date of Patent: June 10, 2003
    Assignee: The Boeing Company
    Inventors: Donald K. Dabelstein, Matthew D. Carter
  • Publication number: 20030075249
    Abstract: A method and device for the controlled tempering of a casting trough integrated between a supply vessel for a molten metal (e.g., copper or a copper alloy), and at least one continuous casting mold. The trough walls and the trough floor of the casting trough are at least partially provided with a lining layer having a specific electrical resistance between 10−1&OHgr;·m to 10−6&OHgr;·m and being resistant to the heat of the molten metal. The lining layer is inductively heated by an electrical heating device arranged around the lining layer.
    Type: Application
    Filed: December 3, 2001
    Publication date: April 24, 2003
    Inventors: Andreas Krause, Dirk Rode, Uwe Quadfasel, Hartmut Olemann, Ralph Frankenberg, Hubertus Bruning
  • Publication number: 20030052123
    Abstract: A method for induction heating a workpiece made of a material such as ferrous material or alloy is carried out by placing a non-magnetic conductive shield in proximity to a current concentrating surface of the workpiece and exposing the workpiece with a shield in place to a time varying magnetic field. The magnetic field induces eddy currents in the surface of the workpiece. The conductive shield is placed in sufficient proximity to reduce or eliminate the eddy currents in the portion covered by the shield. At least a part of the uncovered portion of the workpiece is heated above the austenitizing or solution temperature of the material. At the same time, the covered portions of the workpiece are protected from overheating by the shield. The workpiece is then quenched to complete the hardening process.
    Type: Application
    Filed: September 14, 2001
    Publication date: March 20, 2003
    Inventors: Donald K. Dabelstein, Matthew D. Carter
  • Patent number: 6506269
    Abstract: A high-strength and high-conductivity copper alloy is disclosed which contains essentially of: (a) from 0.5 to 2.5 wt % of Ni; (b) from 0.5 to 2.5 wt % of Co; (c) from 0.5 to 0.8 wt % of Si; (d) from 0.05 to 0.15 wt % of either Mg or P or both; and (e) the balance of Cu. The amounts of Co, Ni, and Si satisfy the following equations: 2%≦(Ni+Co)≦4%, and 0.8≦(Ni/4+Co/6)/Si≦1.2. The new copper alloy exhibits substantially improved electrical conductivity, greater than 65% IACA, than the commercially available C7025 copper alloy, while maintaining a satisfactory tensile strength (greater than 600 MPa), and, thus, can be most advantageously used for preparing leadframes for use in high pin-number (greater than 100 pins) IC application.
    Type: Grant
    Filed: September 21, 2001
    Date of Patent: January 14, 2003
    Assignee: Industrial Technology Research Institute
    Inventors: Jin-Yaw Liu, Yu-Lian Sha, I-Ching Lee, Mao-Ying Teng, Ray-Iun Liu, Ren-Der Jean
  • Patent number: 6498324
    Abstract: An induction heating device is disclosed for heating a rolling roller by induction heating so as to equalize the diameter of the rolling roller. The device includes an induction heater and a means for moving the induction heater to a portion of the roller surface to be heated, while the distance from the induction heater to the surface is maintained constant. An electric power supply means supplies electric power to the induction heater, and a means is provided for adjusting the quantity of heat to be produced by the induction heater according to the quantity of heat that is required by the portion of the roller to be heated. The heat quantity adjusting means includes a frequency control means for controlling the frequency of electric power supplied to the induction heater, wherein the frequency control means adjusts the frequency of electric power within a predetermined frequency range to a frequency which is suitable to produce the quantity of heat required by the portion of the rolling roller to be heated.
    Type: Grant
    Filed: October 15, 2001
    Date of Patent: December 24, 2002
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Mikio Yamamoto, Tatsufumi Aoi, Keiji Mizuta
  • Publication number: 20020185201
    Abstract: The present invention provides a steel product which, while minimizing an increase in hardness after forging to ensure machinability and cold workability, is improved, for example, in fatigue strength in its non-hardened portion and is improved, in its hardened portion, in rolling resistance level, antipitting level, abrasion resistance, and fatigue strength. The high strength steel for induction hardening comprises, by mass, carbon (C): 0.5 to 0.7%, silicon (Si): 0.5 to 1.0%, manganese (Mn): 0.5 to 1.0%, chromium (Cr): not more than 0.4%, and sulfur (S): not more than 0.035% with the balance consisting of iron (Fe) and unavoidable impurities, the steel being forged to produce a component at least a part of which is then inductively hardened before use.
    Type: Application
    Filed: February 1, 2002
    Publication date: December 12, 2002
    Applicant: SANYO SPECIAL STEEL CO., LTD.
    Inventor: Shuhei Kitano
  • Publication number: 20020179203
    Abstract: A system and method for inductively heating and then quench hardening a portion of a workpiece, such as a several threads of a screw or bolt are disclosed. The system includes a conveyor system having a rotary conveyor for separating, aligning, and transporting each of the workpieces in aligned succession through an induction heater positioned about the rotary conveyor to heat-treat at least a portion of each of the workpieces. A sensor determines whether a workpiece is heat-treated to a minimum temperature and causes an ejector to separate heat-treated workpieces that have reached the minimum temperature from heat-treated workpieces that have failed to reach the minimum temperature. The separated workpieces are then quenched in a tank & separately removed automatically.
    Type: Application
    Filed: May 31, 2001
    Publication date: December 5, 2002
    Inventors: Dean P. Stefanac, Thomas J. Bowers, Donald H. Wiseman, William C. Weller
  • Publication number: 20020157739
    Abstract: Apparatus for heat treating a cutting tool comprises a furnace and a tool holder within the furnace adapted to receive therein a first portion of the tool, a second portion of the tool projecting from the tool holder, the second portion of the tool being directly exposed to radiant heat from at least one radiant heating element within the furnace with the first portion of the tool being shielded from the radiant heat.
    Type: Application
    Filed: July 27, 2001
    Publication date: October 31, 2002
    Inventors: Geoffrey Philip Fisher, Richard Mark Lill, Edgar Dabill, Martin John Monaghan, Jonathan Clifford Oates, Graham Monteith Smith
  • Patent number: 6463779
    Abstract: A process and relevant tools for hot forming of high strength metal workpieces by means of applicating high density current to the workpiece directly and generating heat inside it by using its own electrical resistance in order to obtain desired temperature and formability at the desired moment of the forming process without requiring any external heat source or previous heating process. Temperature of the blank is measured by measuring its electrical resistance and by using linear correlation between temperature and resistance. This heating process can be applicated in several metal forming types such as high strength sheet stamping (FIG. 2, FIG. 3), bending (FIG. 3), blow forming (FIG. 4, FIG. 5) in accordance with mechanical operations of the relevant processes. High temperature rates can easily be reached and kept at the desired moment of the forming process without being effected by rapid cooling phenomena resulted by too much heat loss area/mass and heat storage capasitance of thin sheets.
    Type: Grant
    Filed: February 26, 2001
    Date of Patent: October 15, 2002
    Inventor: Mehmet Terziakin
  • Patent number: 6458226
    Abstract: A process for thermomechanical treatment of steel for torsionally-strained spring elements, the initial material being heated with a heating rate of at least 50 K/s and austenitized, and then, being formed in at least one forming step with the formed product being quenched to below the martensite temperature to martensite and then tempered. To improve the strength or toughness properties of the spring steel in the strain direction of the torsionally strained spring elements so that the increase of vibration strength is considerable, the initial material is heated to a temperature above the recrystallization temperature and then formed at such a temperature, that dynamic and/or static recrystallization of the austenite occurs, and that the recrystallized austenite of the formed product is quenched.
    Type: Grant
    Filed: July 20, 1999
    Date of Patent: October 1, 2002
    Assignee: Muhr und Bender
    Inventors: Christian Bilgen, Eberthard Kast, Andreas Kleemann, Hans-Günther Krull, Thomas Muhr, Horst Weiss
  • Patent number: 6455825
    Abstract: A method of monitoring the process of induction heating a workpiece. A miniature magnetic sensor located near the outer surface of the workpiece measures changes in the surface magnetic field caused by changes in the magnetic properties of the workpiece as it heats up during induction heating (or cools down during quenching). A passive miniature magnetic sensor detects a distinct magnetic spike that appears when the saturation field, Bsat, of the workpiece has been exceeded. This distinct magnetic spike disappears when the workpiece's surface temperature exceeds its Curie temperature, due to the sudden decrease in its magnetic permeability. Alternatively, an active magnetic sensor can also be used to measure changes in the resonance response of the monitor coil when the excitation coil is linearly swept over 0-10 MHz, due to changes in the magnetic permeability and electrical resistivity of the workpiece as its temperature increases (or decreases).
    Type: Grant
    Filed: November 21, 2000
    Date of Patent: September 24, 2002
    Assignee: Sandia Corporation
    Inventors: Anthony E. Bentley, John Bruce Kelley, Fred J. Zutavern
  • Publication number: 20020112787
    Abstract: The high-strength race of the present invention comprises using A steel for a high-strength race comprising the following elements in percentage by weight: C: 0.30 to 0.60%, Si: 0.30 to 1.30%, Mn: 0.5 to 1.5%, B: 0.0050% or less, Cr: 0.1 to 0.5%, Mo: 0.1 to 0.5%, Si +Mo: 0.5 to 1.4%, Ni: 0.02 to 1.0%, the balance of Fe and unavoidable impurities, performing induction hardening to make the race have a surface hardness of 58 HRC or more and further a surface hardness of 52 HRC or more even after the surface is tempered at 300° C. The high-strength race is superior in rotating fatigue properties, anti-surface fatigue strength and productivity by a combination of composition control and induction hardening.
    Type: Application
    Filed: November 30, 2001
    Publication date: August 22, 2002
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Shinji Asano, Youichi Watanabe, Tatsuo Iguchi, Kanji Ueno
  • Patent number: 6398881
    Abstract: The invention concerns a wear-resistant camshaft and a method of producing the same. Objects in which the application of the invention is possible and useful are all cast-iron parts which are subject to wear as a result of lubricated friction. The wear-resistant camshaft consists of cast-iron and it has a surface layer consisting of a ledeburitic remelted layer with a high cementite portion, and, lying thereunder, a martensitic hardening zone, whereby according to the invention. a. the remelted layer consists of finely dispersed ledeburitic cementite with thicknesses of ≦1 &mgr;m and a metallic matrix of a phase mixture of martensite and/or bainite, residual austenite, as well as less than 20% finely laminated pearlite with a distance of ≦0.1 &mgr;m between the lamelias, and b. the hardening layer is formed from a phase mixture of martensite and/or bainite, partially dissolved pearlite, and residual austenite.
    Type: Grant
    Filed: May 19, 1999
    Date of Patent: June 4, 2002
    Assignee: Fraunhofer-Gesellschaft zur Förderung der Angewandten Forschung e.V.
    Inventors: Berndt Brenner, Carsten Duschek, Andreas Wetzig, Dietmar Naunapper
  • Patent number: 6398885
    Abstract: A method and apparatus for tempering the shank portion only of die blocks which comprises subjecting the shank portion of a die block or other large metal part to electrical energy derived from induction heating or infrared heating to a controlled depth, preferably just sufficiently deep to temper the shank portion but not sufficiently deep to temper the hardened working portion of the part.
    Type: Grant
    Filed: September 25, 1998
    Date of Patent: June 4, 2002
    Assignee: A. Finkl & Sons Co.
    Inventors: Charles W. Finkl, Algirdas A. Underys
  • Patent number: 6384388
    Abstract: A method of enhancing the bending process of a stabilizer bar by locally pre-heating the stabilizer bar immediately prior to formation. By pre-heating the stabilizer bar, the stress in the stabilizer bar is relieved at the bending areas. This allows larger bars to be formed which would otherwise be outside of machine parameters. In the disclosed embodiments, the stabilizer bar is locally heated by induction coils or resistance heating at the bend areas.
    Type: Grant
    Filed: November 17, 2000
    Date of Patent: May 7, 2002
    Assignee: Meritor Suspension Systems Company
    Inventors: Gerald D. Anderson, John M. Khoury, Michael W. Mattice, Thomas M. Drouillard, Kermit G. Rowe, III, David Ian Fretwell, Alistair Bruce Christian Lovatt
  • Patent number: 6383315
    Abstract: A steel profile clamp is used to join flanged component parts. The profile clamp has at least partially conical side walls that are bent radially inwardly. The profile clamp has welding joints to maintain the shape of the clamp. The steel is martensitic for increased load-carrying capacity of the joint. The steel material, in an ambient temperature range of 20° C. to 750° C., has a coefficient of thermal expansion that is at least 0.3×10−6 m/m° C. lower than that of the coefficient of thermal expansion of a ferritic casting material. The method for manufacturing the profile clamp includes prequenching and tempering the material of the profile clamp when it is in the form of a strip. After forming and welding the profile clamp, the weld is subject to induction tempering.
    Type: Grant
    Filed: October 25, 2000
    Date of Patent: May 7, 2002
    Assignees: Rasmussen GmbH, Asea Brown Boveri AG
    Inventors: Hans-Jürgen Kreipe, Claus Dieter Weisheit
  • Patent number: 6300608
    Abstract: There are provided an induction heating coil for carrying out high frequency induction heating (heating during movement) of a hot rolled steel or the like by surrounding the hot rolled steel or the like which is placed on a plurality of conveying rollers and conveyed, and an induction heating apparatus using this induction heating coil. In an induction heating coil 2 for induction heating a heated body (a thin slab 8 or the like) by surrounding it, a first coil portion 13 wound in a spiral form while transferring in one direction (the direction of the arrow mark &agr;) along a coil axis S and a second coil portion 14 which is connected to a terminal (turn point 18) of the first coil portion 13 and wound back while transferring in the other direction (the direction of the arrow mark &bgr;) along the coil axis S are combined so as to overlap in the non-contact state.
    Type: Grant
    Filed: October 12, 1999
    Date of Patent: October 9, 2001
    Assignees: Denki Kogyo Co., Ltd., Chugai Ro Co., Ltd.
    Inventors: Hideo Inoh, Suetaka Omura, Takashi Fujisawa, Hiroyuki Fuchigami
  • Patent number: 6264768
    Abstract: A method and apparatus disclosed for cost-effective net shape precision ausform finishing the engagement surfaces of ball and roller bearings, for enhancing the surface strength and durability of bearing inner and outer races. The method consists of induction heating to austenitize the contacting surface layers of rolling element bearing races, followed by martempering (or marquenching), and then net shape roll finishing of the induction heated contacting surface layers in the metastable austenitic condition to finished dimensional accuracy requirements, and finally cooling to martensite. The apparatus utilizes a fixed vertical through-feed axis for the workpiece bearing race with capability for rotation and linear up and down positioning motion, and two coordinated and controlled laterally-moving infeed axes for roll finishing tooling dies.
    Type: Grant
    Filed: April 23, 1999
    Date of Patent: July 24, 2001
    Assignee: The Penn State Research Foundation
    Inventors: Nagesh Sonti, Suren B. Rao
  • Patent number: 6187118
    Abstract: A method of heat-treating a work piece of high-alloy steel by hardening involves relatively briefly annealing the work piece before hardening, followed by cooling the work piece. The brief annealing that is performed before the actual hardening and the ensuing cooling results in homogeneity of the material in the microscopic range. Following the annealing, the work piece is hardened, for instance by quenching in a salt bath, to achieve a super fine distribution of globular carbides in the microscopic structure with considerably reduced size as compared to the outset state. Also, the microscopic structure created by the method of the invention has improved toughness properties as well as increased microscopic structure stability to aging and leads to a longer service life.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: February 13, 2001
    Assignee: SKF GmbH
    Inventor: Wolfgang Nierlich
  • Patent number: 6171416
    Abstract: At least both ends of a sheet bar in the length direction, which is obtained by roughly rolling a steel slab including 0.1 wt % or less of C, 0.5 wt % or less of Si, 1.0 wt % or less of Mn, 0.1 wt % or less of P, 0.05 wt % or less of S, 0.20 wt % or less of Al, and 0.015 wt % or less of N, are heated so that the temperature at both ends of the sheet bar in the length direction is 15° C. or more higher than the temperature of the remainder of the sheet bar. The rolling finish temperature is Ar3+20° C. to Ar3+100° C. in both end portions of the sheet bar in the length direction, and Ar3+10° C. to Ar3+60° C. in the remainder, and the rolling finish temperature in the both end portions in the length direction is 10° C. or more higher than that of the remainder, so that a steel strip after cold rolling and annealing has r values within ±0.3 of the average r value, and &Dgr;r within ±0.
    Type: Grant
    Filed: October 26, 1999
    Date of Patent: January 9, 2001
    Assignee: Kawasaki Steel Corporation
    Inventors: Makoto Aratani, Yukio Kobata, Hideo Kuguminato, Akio Tosaka, Masatoshi Aratani, Susumu Okada
  • Patent number: 6149740
    Abstract: A method of and apparatus for manufacturing hot-rolled steel strips from a continuously cast primary material, preferably thin slabs, in a plurality of successive steps in a continuous operation is disclosed. In the invention, thin slabs, which leave an equalizing furnace, are heated above the maximum temperature that can be achieved in the equalizing furnace and are thereafter are broken down in a break-down train, with the broken-down thin slabs being subsequently recrystallized and cooled down to a rolling temperature before being finish-rolled in the finishing train.
    Type: Grant
    Filed: April 13, 1998
    Date of Patent: November 21, 2000
    Assignee: SMS Schloemann-Siemag Aktiengesellschaft
    Inventors: Wilfried Bald, Dieter Rosenthal
  • Patent number: 6093268
    Abstract: In a corrective tempering method and apparatus for a rolling element in which the thermal deformation of the rolling element is corrected within an extremely short time by utilizing plasticity exhibited during a metallic structure transforming process brought about by low-temperature tempering of the rolling element made of steel, the hardened rolling element is heated and pressured to a maximum temperature within a range of from 250 to 500.degree. C. by a heating device while set in correcting molds to correct the deformation of the rolling element at a degree of working within a range not exceeding an elastic deformation range of the rolling element at a room temperature. The rolling element can be heated also by an induction heating device in addition to a conduction heating device. A product whose inner/outer diameter correcting degree of deformation is 60% or more, dimension standardizing rate is 30% or more, surface roughness is less than Ra 0.2 .mu.
    Type: Grant
    Filed: April 24, 1996
    Date of Patent: July 25, 2000
    Assignee: NSK Ltd.
    Inventors: Kiyoshi Hirakawa, Akitoshi Maeda, Hiroaki Sugiyama, Manabu Ohhori
  • Patent number: 6083329
    Abstract: A gas shielding apparatus comprising a main gas jacket having induction heating means, and front gas jacket and rear gas jacket integrally disposed at supply side and discharge side of a member to be bonded or a member to be heated of the main gas jacket, wherein gas shielding is achieved by setting the internal pressure of the main gas jacket lower than the internal pressure of the front gas jacket and rear gas jacket, so that the holding time of the shielding gas jacket in the main gas jacket becomes long.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: July 4, 2000
    Assignee: Daido Tokushuko Kabushiki Kaisha
    Inventors: Masaki Tsuchiya, Hiroaki Suzuki
  • Patent number: 5972129
    Abstract: Process for smelting a titanium steel according to which a liquid steel containing more than 0.003% of nitrogen and not containing titanium is smelted and then more than 0.005% of titanium is introduced into the liquid steel by progressive diffusion from an oxidized phase containing titanium and the steel is solidified. Steel obtained by the process.
    Type: Grant
    Filed: November 30, 1995
    Date of Patent: October 26, 1999
    Assignee: Creusot Loire Industrie
    Inventors: Jean Beguinot, Jean-Luc Beau, Marie-Luce Nectoux
  • Patent number: 5972134
    Abstract: The invention is directed to a process for the manufacture of a metallic molded structural part (1) for motor vehicle components such as door impact girders or bumpers with areas (2) with a higher ductility in relation to the rest of the structural component part. For this purpose, partial areas (2) of a plate (5) are initially heated to a temperature of 900.degree. C. within a period of less than 30 seconds. Subsequently, the thermal-treated plate (5') is shaped in a pressing tool (7) to form the molded structural part (1) and is heat-treated in the pressing tool (7).
    Type: Grant
    Filed: October 14, 1997
    Date of Patent: October 26, 1999
    Assignee: Benteler AG
    Inventors: Otto Buschsieweke, Udo Klasfauseweh, Gunther Fortmeier
  • Patent number: 5935352
    Abstract: A process for production of a steel component having a hard, carbon rich dissolved surface and a tough, low carbon dissolved core, incorporating the following steps:using an alloyed steel with a carbon content of 0.3%-1.2% C and with an alloy element acting as a strong carbide former; andsubjecting a component formed from this material to induction heating, whereby the core is heated to a level in the lower region of the austenite area, thereby creating a certain dissolved low carbon level in the component core, and rapidly heating the surface region to a higher region within the austenite area, thereby creating a high dissolved carbon content in the surface region of the component.
    Type: Grant
    Filed: May 19, 1997
    Date of Patent: August 10, 1999
    Assignee: Ovako Steel AB
    Inventor: Jan-Erik Andersson
  • Patent number: 5906691
    Abstract: Improved fatigue strength properties are achieved in an induction hardened microalloy steel useful for demanding service environments. The microalloy steel has low carbon and sulfur contents, comprising in % by weight, 0.15% to 0.45% C, 0.50% to 1.60% Mn, up to 0.20% V, 0.0001% to 0.01% S, balance Fe. The material is fabricated to a selected configuration, such as an engine crankshaft, for example. Selected surfaces of the fabricated article are hardened by induction heating. The article can be used directly after induction hardening or it may be tempered at low to moderate temperatures of from about 100.degree. C. (200.degree. F.) to 290.degree. C. (550.degree. F.) to achieve a desired surface hardness and compressive residual stress level. The controlled alloy chemistry and low tempering temperature provide a substantial increase in bending fatigue strength over conventional higher carbon grade steels.
    Type: Grant
    Filed: September 16, 1997
    Date of Patent: May 25, 1999
    Assignees: The Timken Company, Cummins Engine Company, Inc.
    Inventors: Michael E. Burnett, Carl F. Musolff