Localized Or Zone Heating Or Cooling Patents (Class 148/639)
  • Patent number: 6511559
    Abstract: A process for producing wear-resistant edge layers in precipitation-hardenable materials wherein a component that was conventionally solution annealed and subsequently subjected to a conventional aging heat treatment is subjected to another short-time solution annealing affecting only the edge layer of the component, whereafter another aging heat treatment that evenly includes the interior of the component and its edge layer is carried out.
    Type: Grant
    Filed: December 15, 2000
    Date of Patent: January 28, 2003
    Assignee: Fraunhofer-Geselleschaft zur Foerderung der angewandten Forschung e.V.
    Inventors: Berndt Brenner, Frank Tietz
  • Patent number: 6488788
    Abstract: A flat plate member with gear portion is formed to a predetermined shape by pressing a flat steel raw material having a composition comprising, by weight, 0.10-0.18% C, less than 0.03% Si, 0.60-1.50% Mn, less than 0.020% P, less than 0.013% S, 0.001-0.004% B and the balance Fe with inevitable impurities, wherein quenching is performed on only the gear portion.
    Type: Grant
    Filed: June 28, 2001
    Date of Patent: December 3, 2002
    Assignee: Aisin Seiki Kabushiki Kaisha
    Inventors: Haruki Ito, Yukio Isomura, Naoyuki Yamada
  • 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: 6458220
    Abstract: Steel alloys susceptible to case and core hardening comprise 0.05 to 0.24 weight percent carbon; 15 to 28 weight percent cobalt and 1.5 to 9.5 weight percent in nickel, small percentages of one or more additives: chromium, molybdenum, and vanadium; and the balance iron. Blades for ice skating or other sports equipment made from such alloys provide predictable and reproducible characteristics and permit fabrication with hardened edges on a ductile, strong substrate or base.
    Type: Grant
    Filed: September 19, 2000
    Date of Patent: October 1, 2002
    Assignee: Northwestern University
    Inventors: Charles J. Kuehmann, Priscilla A. Bernikowicz, Gregory B. Olson, John P. Wise, Carelyn E. Campbell
  • 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: 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: 6398886
    Abstract: A process of finishing outer joint parts formed in a non-cutting way and intended for constant velocity joints, said outer joint parts having a longitudinal axis and an inner recess which extends in the direction of the longitudinal axis and which, in the direction of the longitudinal axis, is substantially undercut-free, with the inner recess being provided with tracks which comprise contact zones for the rolling contact of rolling contact members, characterized by the following sequence of process stages: non-cutting forming of the outer joint part, surface-layer-hardening of the inner recess at least along the length of the contact zones, for the purpose of producing a hardened surface layer, at least in the region of the contact zones above an unhardened matrix, calibrating the contact zones in respect of their radial positions and axial linearity by displacing the hardened surface layer in the region of the contact zones within the unhardened matrix.
    Type: Grant
    Filed: June 22, 2001
    Date of Patent: June 4, 2002
    Assignee: GKN Automotive AG
    Inventors: Peter Fuhrmann, Hans-Willi Kinzel
  • Publication number: 20020026966
    Abstract: Via a first path (P1) which extends for continuous treatment from one longitudinal end to the other of a cylinder head (H) passing between pairs of exhaust ports (15) and pairs of intake ports (14) opposed to each other with respect to one cylinder and which terminates in a tension bolt hole (21), and via second paths (P2P5) which, after treatment by this first path (P1), extend for successive treatment from cylinders adjacent the terminal point of the first path (P1) and between a pair of exhaust ports (15) and a pair of intake ports (14) opposed to each other and which terminate in tension bolt holes (21), the surface of the cylinder head (H) is stirred for refining without melting it by the heat from a rotating tool.
    Type: Application
    Filed: August 27, 2001
    Publication date: March 7, 2002
    Inventors: Seiji Nomura, Toshiyuki Gendou
  • Patent number: 6344098
    Abstract: A heat treatment process is provided that produces a monoblock, low alloy steel rotor for use in low pressure steam turbines. The process includes austenitizing the rotor at a substantially uniformly applied treatment temperature of about 840° C., quenching the rotor, and then differentially tempering the rotor at different axial locations. The rotor is tempered in a furnace divided into regions by refractory boards enabling different temperatures in each divided region to be maintained. A higher than normal strength condition is achieved in one or more axial locations along the rotor by subjecting the location(s) to a lower tempering temperature. The axial location(s) being tempered at lower temperature approximate those locations less susceptible to stress corrosion cracking whereby increased strength is provided the rotor without increasing net susceptibility to stress corrosion cracking.
    Type: Grant
    Filed: December 8, 2000
    Date of Patent: February 5, 2002
    Assignee: General Electric Company
    Inventors: Michael Patrick Manning, Robin Carl Schwant
  • Patent number: 6273974
    Abstract: A selectively hardened nail includes a nail head, an elongated shank, and a tip. A portion of the nail shank is made harder than the remainder by selectively heat treating that portion, and cooling it. The nail has controlled bending properties. The selectively hardened portion does not significantly bend when the nail is fired at a surface using a power driving tool, or during use of the nailed object.
    Type: Grant
    Filed: May 15, 2000
    Date of Patent: August 14, 2001
    Assignee: Illinois Tool Works Inc.
    Inventors: Geronimo E. Lat, Louis M. Spoto, Kent B. Godsted
  • Patent number: 6221185
    Abstract: The invention relates to a method for manufacturing components from critical cold forming of light metal strip, preferably naturally hard Al alloys of the AlMg or AlMg—Mn types, in which the desired component is manufactured from the strip by at least one cold forming step and the plasticity is improved before the cold forming by means of a soft annealing. According to the invention, it is proposed that the region of the longitudinal edges of the cold-slit strips is heated in a depth in the strip width of at least 1 mm to a maximum of 10 mm in such a way that a temperature of over 150° C. is reached over a time span of more than 0.1 seconds to a maximum of 10 seconds.
    Type: Grant
    Filed: February 26, 1999
    Date of Patent: April 24, 2001
    Assignee: Michelin Kronprinz Werke GmbH
    Inventors: Wolfgang Tanzmann, Helmut Tümmler, Ralf Duning, Uwe Gohrbandt, Peter von Czarnowski, Gerhardt Söllner
  • Patent number: 6193820
    Abstract: A method for the thermal treatment of bushings, particularly for tracked vehicles and the like, which provides for a first step, during which external quench hardening of the bushing is performed by heating through to approximately {fraction (7/10-10/10)} of the thickness of the bushing, followed by cooling with quenching liquid; then a second step for internal quench hardening is performed by heating the bushing through to approximately {fraction (4/10-7/10)} of the thickness thereof and then cooling with quenching liquid; the method ends by performing a step for the stress relieving of the bushing. A product at low costs can thus be obtained which has better wear resistance and fatigue strength than observed in bushings obtained with conventional methods.
    Type: Grant
    Filed: October 27, 1997
    Date of Patent: February 27, 2001
    Inventors: Bruno Girardello, Pierangelo Girardello, Giampaolo Girardello
  • Patent number: 6193173
    Abstract: The invention relates to a burner including an injector one end zone (33) of which can be taken to high temperatures during operation of the burner. This end zone is made of an alloy comprising between 16 and 22% by weight of Cr, between 3 and 6% by weight of Al, between 0.1 and 1.0% by weight of Ti, between 0.1 and 1.0% by weight of Y2O3, and between 70 and 80% by weight of Fe. The burner can be used in a furnace in the glassmaking industry.
    Type: Grant
    Filed: June 15, 1999
    Date of Patent: February 27, 2001
    Assignee: L'Air Liquide Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Pierre Bodelin, Patrick Recourt, Annie Meyer, Jean-Paul Guedra
  • 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: 6139655
    Abstract: A selectively heat treated side intrusion beam includes a beam body having a center portion heat treated and end portions not heat treated. The beam body is affixed to end brackets that couple the beam body to the automotive vehicle door. The method for forming a side intrusion beam includes the steps of moving beam stock through a heater; controlling the heater to cycle between an on-state and an off-state with respect to predetermined portions of the length of the beam; quenching the beam stock; and, cutting the beam stock at untreated portions to form the beam body.
    Type: Grant
    Filed: December 17, 1998
    Date of Patent: October 31, 2000
    Assignee: Trim Trends, Inc.
    Inventors: Daniel J. Kowalski, Ben Kowalski, Edward Rowady
  • Patent number: 6108908
    Abstract: A combustion chamber housing for use in an airbag deployment system has a tubular body portion having a length and defining a combustion chamber that is adapted to contain combustion materials and to contain gases produced from the combustion thereof. The body has an expanded region having an edge defining an opening. The edge and a portion of the body adjacent to the edge and extending longitudinally therefrom along the body is heat-treated and defines a heat-treated, strengthened region. A method for heat treating the housings is also disclosed.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: August 29, 2000
    Assignee: Illinois Tool Works
    Inventors: Michael Starozhitsky, Edward Kawecki
  • Patent number: 6074765
    Abstract: A grinding rod chemistry enhances wearability and durability of a steel rod and comprises levels of carbon to achieve a surface hardness in excess of 55 Rockwell C and levels of chromium which achieve significant depth in the formed outer martensite shell. The grinding rod has a core greater than 99% pearlite with a hardness less than 45 Rockwell C and the end portions of the rod are soft and have a hardness less than 35 Rockwell C. The steel bar of the selected chemistry is treated by reheating to above its austenitising temperature, transferring with minimal cooling to an open tubular quench vessel while securing the bar in the vessel to minimize bar warping, introducing quench water into the inlet end of the vessel and passing the liquid through the vessel to ensure uniform heat removal. The outer martensite shell is tempered by allowing the bar to soak back after quenching.
    Type: Grant
    Filed: June 3, 1998
    Date of Patent: June 13, 2000
    Assignee: Stelco Inc.
    Inventor: Robert William Pugh
  • Patent number: 6063218
    Abstract: In a method of manufacturing a bearing, a high-frequency hardened steel essentially containing the following elements in the following percentage by weight is employed as the material of at least one of the outer and inner races of the bearing which is drilled,C; 0.5 to 0.65%, Si; 0.07 to 0.15%,Mn; 0.05 to 0.35%, Cr; 0.25 to 0.55%, andB; 0.0035% or less,a workpiece 10 Hv 230 in maximum hardness is formed with the high-frequency hardened steel subjected to hot forging, a part of the workpiece where a hole 12 is to be formed is drilled, and a part of the workpiece 10 where a track 14 is formed is subjected to high-frequency hardening until it becomes at least Hv 653 in hardness. The workpiece formed with the steel material subjected to hot forging is not larger than Hv 230 in maximum hardness. Hence, the workpiece can be drilled without reduction of the service life of the drilling tool, and the track region of the bearing has a hardness value which is practical in use.
    Type: Grant
    Filed: August 10, 1993
    Date of Patent: May 16, 2000
    Assignee: NSK Ltd.
    Inventors: Tomoki Muraoka, Masayuki Kobayashi
  • Patent number: 6059899
    Abstract: A press-formed article has a quenched area and a required strength distribution. The quenched area has a hardness distribution exhibiting a hardness transition which corresponds to the required strength distribution. The press-formed article may include one end portion, the other end portion, and a central area disposed between the one end portion and the other end portion. The quenched area is extended from the one end portion and to the other end portion. The hardness distribution of the quenched area exhibits a condition that hardness is the highest in the central area in such a manner that hardness is gradually decreased from the central area to the one end portion and to the other end portion.
    Type: Grant
    Filed: June 19, 1997
    Date of Patent: May 9, 2000
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masashi Shibata, Masazumi Onishi, Shinji Kurachi, Kouji Makino
  • 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: 5916387
    Abstract: This invention concerns a method of reducing the gaping values of railway tracks made of steel to less than 3.6 mm. It is characteristic of this invention that the rolled and leveled rails are heated briefly, i.e., for approx. 10 to 25 sec, until reaching a maximum temperature of 100.degree. C. in the rail head and a maximum of 260.degree. C. in the web, and then they are allowed to cool again immediately.
    Type: Grant
    Filed: August 13, 1997
    Date of Patent: June 29, 1999
    Assignee: Thyssen Stahl AG
    Inventors: Robert Dannenberg, Herbert Schmedders, Jurgen Scharlack
  • Patent number: 5911844
    Abstract: A method for drawing a portion of metallic material having a known hardness. The method includes the step of applying a localized heat treatment to predetermined portions of the metallic material. Additionally, the method comprises forming the localized heat treated regions into a desired drawn or stamped configuration, wherein the configuration is substantially devoid of cracks.
    Type: Grant
    Filed: February 21, 1997
    Date of Patent: June 15, 1999
    Assignee: Alumax Extrusions Inc.
    Inventor: Joseph C. Benedyk
  • 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
  • Patent number: 5902423
    Abstract: A process for heat treating a steel bar to produce a grinding rod having a softer core of at least 99% pearlite and having a hardness of less than 45 Rockwell C, an outer shell of martensite having a hardness of at least 50 Rockwell C and softer end portions having a hardness of less than 35 Rockwell C, where the softer end portions each having an engineered heat treated length less than 15 cm, comprises reheating a formed steel bar to above its austenitising temperature, transferring with minimal cooling the reheated bar to an open tubular quench vessel while securing the bar in the vessel to minimize bar warping in the vessel during quenching, introducing quench water into an inlet end of the vessel and passing the quench liquid along the vessel at high surface velocities exceeding 4 meters per second relative to bar surface to minimize thereby production of steam along the bar length and ensure uniform heat removal and removing quench water at an outlet end of the vessel, quenching the bar in the vessel fo
    Type: Grant
    Filed: March 16, 1998
    Date of Patent: May 11, 1999
    Assignee: Stelco Inc.
    Inventor: Robert William Pugh
  • Patent number: 5858136
    Abstract: Copper wire coated with a layer of zinc is heated to a temperature (T.sub.1) sufficient for the formation of a brass phase .beta., and the temperature is maintained until complete diffusion of the zinc. The thickness of the zinc covering can be chosen in such a way that once the zinc is completely diffused, the wire consists of a brass phase .beta. in its periphery and of copper in its central part. The wire is then heated to a temperature (T.sub.2) necessary for the formation of brass phase .alpha., and the central copper part of the wire is transformed into brass phase .alpha..
    Type: Grant
    Filed: December 9, 1996
    Date of Patent: January 12, 1999
    Assignee: Charmilles Technologies SA
    Inventor: Jean Paul Briffod
  • Patent number: 5840136
    Abstract: A bainite forming process for treating a steel material reduces the time required for a complete thermal treatment as well as the cycle time for the thermal treatment device without necessitating any special means for handling the steel material. The steel material is heated to a temperature higher than the austenitic transformation point, and temporarily quenched to an intermediate point temperature higher than the martensitic transformation point. Then, the temperature of the steel material is again raised towards the range corresponding to bainitic transformation to form a bainitic structure. The reheating is discontinued before the temperature corresponding to the austenitic transformation point is reached, and the steel material is then quenched. In the heating steps, only the portion to be treated by the bainite forming process is locally irradiated with a high-density energy beam.
    Type: Grant
    Filed: March 4, 1997
    Date of Patent: November 24, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Michio Maruki, Kouji Ohbayashi, Takatoshi Suzuki
  • Patent number: 5814167
    Abstract: The stamped-metal clip is suitable for use with an endless track belt cooperating with slide rails. The clip comprises a main portion having a hardened bearing surface to be engaged against at least one of the slide rails. The bearing surface has a hardness greater than 35 HRC, preferably between 40 and 60 HRC. The clip further comprises an unhardened fastening portion comprising two curved wings to clamp the main portion to the track belt without rupture. These curved wings have a hardness smaller than the hardness of the bearing surface, preferably smaller than 35 HRC. The hardness of the bearing surface makes it resistant to wear and friction and the smaller hardness of the wings enables the clip to be clamped to the track belt without rupture.
    Type: Grant
    Filed: December 27, 1996
    Date of Patent: September 29, 1998
    Inventor: Maurice Beaudoin
  • Patent number: 5808233
    Abstract: A thermocouple formed of a length of a single composition having first solid phase section adjoining a second solid phase section, and a transition therebetween. One method of making such thermocouples is to raise the temperature of the first solid phase section above its transformation temperature while maintaining the temperature of a second adjoining solid phase section of the length of material below its transformation temperature. A second method includes rapidly solidifying a molten material by contacting it with a moving substrate formed of adjoining regions of differing thermal conductivity. A third method includes rapidly solidifying a molten material by alternatingly contacting it with a cooling fluid and air. A fourth method includes transforming a section of a length of material in a first solid to a second solid phase by mechanical means.
    Type: Grant
    Filed: July 15, 1996
    Date of Patent: September 15, 1998
    Assignee: Temple University-Of The Commonwealth System of Higher Education
    Inventors: Mikhail V. Finkel, Jim J. S. Chen, Antonio M. Goncalves
  • Patent number: 5800641
    Abstract: A method of thermal or thermochemical treatment of precision steel components having different wall thicknesses comprising the steps of a) hardening (8), b) low temperature cooling (9) and c) annealing (10), wherein the precision steel components are subjected to a low temperature cooling of only selected parts of the precision steel component to effect a reduction in the occurrence of primary residual austenite in the selected parts thereof.
    Type: Grant
    Filed: March 18, 1996
    Date of Patent: September 1, 1998
    Assignee: Ina Walzlager Schaeffler KG
    Inventor: E.H. Georg Schaeffler
  • Patent number: 5788034
    Abstract: A lockup clutch for torque converter which prevents engaging and disengaging shock when a transmission torque suddenly changes, includes a lockup clutch assembly, a lockup clutch piston operating the lockup clutch assembly, and a damper device disposed between the lockup clutch piston and an output member for absorbing changes of transmission torque occurring in association with the operation of the lockup clutch assembly. The lockup clutch piston is made of steel and has a thermally treated portion placed at a surface in contact with springs of the damper device wherein the thermally treated portion is hardened by rapid local melting with high density energy radiation such as electron beam followed by rapid cooling.
    Type: Grant
    Filed: April 17, 1996
    Date of Patent: August 4, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Michio Maruki, Takao Taniguchi, Masataka Shimazaki, Fumitomo Yokoyama, Hideji Kato, Kouji Ohbayashi, Yoshimi Watanabe, Naohisa Momiyama, Masayoshi Imakire
  • Patent number: 5707181
    Abstract: A method of producing an intended breaking point at a predetermined location of a tension member for a soil anchor of a strain-hardened steel or a steel which is not which is not in a thermodynamic equilibrium, for example, a wire or a steel wire strand, to enable removal of the free steel length after use by applying a tensile force which exceeds the working load. The predetermined breaking point is obtained by heating the tension member at a predetermined location in a controlled manner to a temperature at which the state of strain-hardening or the state of being not in a thermodynamic equilibrium is at least partially cancelled, wherein the predetermined breaking point has a breaking load which is equal to or smaller than the breaking load of the untreated tension member, but greater than the yield point of the untreated tension member.
    Type: Grant
    Filed: January 3, 1996
    Date of Patent: January 13, 1998
    Assignee: Dyckerhoff & Widmann Aktiengesellschaft
    Inventors: Hans-Peter von Allmen, Reinhard Klockner, Erich Richartz
  • Patent number: 5501639
    Abstract: A constant velocity universal ball joint has an outer joint part and an inner joint part. Each part is provided with a plurality of ball tracks extending substantially in a longitudinal direction. The balls provide torque transmission and are guided in radially opposed tracks in the outer joint part and in the inner joint part. A cage with cage windows holds each ball in a plane positioned perpendicularly relative to the longitudinal axis. The cage includes a mechanism which, if the axes of the outer joint part and the inner joint part deviate from one another, guide the cage with the balls on to the angle-bisecting plane. Each of the track faces of the ball tracks, at the outer joint part and/or at the inner joint part, are subjected to loads by the balls, as well as each of the regions of the surfaces adjoining the ball tracks, which are guiding faces for the cage, undergo a hardening operation. Also, unhardened zones are provided between each two ball tracks between the guiding faces.
    Type: Grant
    Filed: January 13, 1993
    Date of Patent: March 26, 1996
    Assignee: GKN Automotive AG
    Inventor: Werner Krude
  • Patent number: 5390900
    Abstract: An apparatus and method for cooling a metal strip, the apparatus having a header that receives and directs a curtain of water across the strip, a water collector on one side of the curtain of water and a source of air on the opposite side of the curtain of water arranged to direct a flow of air across the curtain of water and divert water into the water collector. A deflector is arranged to interrupt at least a portion of the flow of air such that at least a portion of the wall of water contacts and cools the strip of metal. The flow of air is provided at a pressure of about 50 to 100 psi and, with the flow of air completely blocked by a deflector, the strip of metal is cooled completely across the width of the strip.
    Type: Grant
    Filed: April 26, 1994
    Date of Patent: February 21, 1995
    Inventor: Vladimir B. Ginzburg
  • Patent number: 5248354
    Abstract: A unique method is proposed for the preparation of a body of an austempered ductile cast iron having a gradient of the mechanical property within the body by subjecting a body of a nodular graphite cast iron to an isothermal transformation treatment for austempering at a temperature in the range from 250.degree. to 450.degree. C. while the body has a temperature difference between two points or between two surfaces. The temperature difference can be produced by bringing the two points or two surfaces into contact with melts of a salt kept at different temperatures. A two-compartment salt-bath apparatus therefore is disclosed.
    Type: Grant
    Filed: September 18, 1992
    Date of Patent: September 28, 1993
    Assignee: Agency of Industrial Science and Technology
    Inventors: Shuji Tada, Toshio Takahashi, Toshihiko Abe
  • Patent number: 5238510
    Abstract: Disclosed is a method for producing a metal sheet having a full-hard central portion extending between at least two softer side edge portions of the sheet. The method comprises the step of heating the side edge portions of the sheet portions of the sheet to a higher temperature than the central portion.
    Type: Grant
    Filed: December 4, 1991
    Date of Patent: August 24, 1993
    Assignee: Bethlehem Steel Corporation
    Inventors: Ronald J. Dutton, Robert E. Forbes, Herbert E. Townsend, Jr.