Abstract: A method is provided including heating a workpiece beyond a transformation temperature. The workpiece has at least one internal surface that has a nominal diameter, and a transformation diameter that corresponds to the start of a transformation from a first state to a second state. The method includes inserting a quench plug assembly into the workpiece. The quench plug assembly includes at least one contact surface. The at least one contact surface has a diameter that is larger than the nominal diameter and at least as large as the transformation diameter. The method includes quenching the workpiece with the quench plug assembly disposed in the bore of the workpiece. The at least one internal surface is contacted and restrained by the at least one contact surface while the workpiece transforms from the first state to the second state. Also, the method includes removing the quench plug assembly from the workpiece.

Abstract: When temperature of lubricating oil is raised at a time of low-temperature, of an outer peripheral side of a radial plain bearing in a bearing retaining unit, heat is not supplied from a heating medium in a thermal medium flow path on the outer peripheral side of a halved bearing metal in a bearing retaining unit body, which has a large thermal capacity, and instead, heat is supplied from the heating medium in the thermal medium flow path on the outer peripheral side of a halved bearing metal in the cap, which has a small thermal capacity.

Abstract: A method of heat-treating a rack bar includes a step of continuously conveying a rack bar provided with a rack teeth portion and a ball screw portion by a quenching means, and a step of sequentially applying a quenching treatment to each circumferential surface of the rack teeth portion and the ball screw portion. The quenching treatment is preferably and sequentially applied to each entire circumferential surface of the rack teeth portion and the ball screw portion.

Abstract: An apparatus is disclosed for performing thermomechanical processing of gears in which precise control of the thermal, metallurgical and mechanical action during the forming process is maintained. The apparatus comprises an induction heating system which reaustenitizes the surface of the gear with minimum decarburization, a material transfer system which provides timely operations on the work piece, tooling and fixture adjustments which provide accurate initial conditions for forming, and a process control architecture that provides the precise sequence and timing necessary to achieve metallurgically sound and dimensionally accurate gears. The induction heating cycle can be controlled from the peak, average or minimum gear surface temperature detected with a high response optical pyrometer. An inert environment is maintained around the workpiece during the induction heating and transfer to quenching above the M.sub.s temperature.

Abstract: A steering rack shaft having a shaft body and rack teeth formed in a predetermined axial region of the shaft body. This steering rack shaft is formed such that a workpiece is quenched, and is then heated for a predetermined time at a temperature exceeding 400.degree. C. so as to be thermally refined, and the rack teeth are subsequently formed. After the formation of the rack teeth, high-frequency induction hardening is provided to form a teeth-hardened layer. Hence, the machining of the rack teeth is facilitated while reducing strain, and the rigidity and toughness of the overall steering rack shaft are improved.

Abstract: A method and apparatus for carrying out scaleless inductive heating of ferrous parts comprising (i) using an integrated manifold-inductor quenchant device, and while gradually flowing a diluted combustible gas into the spacing between the inductor and part surface to be heated, inductively heating such surface as part of a heat treating cycle; and (ii) concurrently stopping such flow and injecting a fluid quenchant through the spacing to rapidly lower the temperature of the part surface to complete the heat treating cycle. Advantageously such method may further comprise flushing the spacing between the inductor and heated part surface, and then repeating the steps of the prior method to treat more parts with the same inductor.

Abstract: A contour hardening apparatus for flat steel work pieces, such as gears, having convoluted surfaces around their circumferences, the apparatus including an annular inductor housing, a mandrel in the center of the inductor housing, and air bearing rotatably mounting the work piece on the mandrel, an air nozzle on the inductor housing aimed at the convoluted surfaces and operative in an ON condition to direct a jet of compressed air against the convoluted surfaces to develop on the work piece a first turning moment in a first direction to rotate the work piece in the first direction during heating, an oil manifold on the inductor housing supplied with oil under pressure and including a first plurality of oil nozzles in the plane of the work piece each oriented to direct a jet of oil at the convoluted surfaces to develop on the work piece a second turning moment opposite the first turning moment, and means to supply the oil manifold with oil under pressure when the air nozzle is in an OFF condition.

Abstract: An apparatus is disclosed for performing thermomechanical processing of gears in which precise control of the thermal, metallurgical and mechanical action during the forming process is maintained. The apparatus comprises an induction heating system which reaustenitizes the surface of the gear with minimum decarburization, a material transfer system which provides timely operations on the work piece, tooling and fixture adjustments which provide accurate initial conditions for forming, and a process control architecture that provides the precise sequence and timing necessary to achieve metallurgically sound and dimensionally accurate gears. Using this invention the induction heating cycle can be controlled from the peak, average or minimum gear surface temperature detected with a high response optical pyrometer. An inert environment is maintained around the workpiece during the induction heating and transfer to quenching above the M.sub.s temperature.

Abstract: A method for induction heating and quench hardening of helical gears provides a hardness pattern uniformly distributed to a controlled depth across and between the teeth surfaces by means of axial scanning of the workpiece and uniform quenching. Uniform quenching is achieved by directing jets of quench fluid at the workpiece toothed surface at angles horizontally offset from the radial direction.

Abstract: A method for the inductive hardening of working surfaces and transition radii on crankshafts in which, to receive connecting rods, crank pins are disposed directly one after another at different angular attitudes in planes at right-angles to the axis of rotation is disclosed. By the subject invention, adjacently disposed inductors are applied against the crank pins from the same side. Both inductors are disposed in the region between the two serially disposed crank pins and are spaced apart from each other.

Abstract: A device for induction heating of the inside of cylinder liners of reciprocating-piston engines to a transformation temperature, for the purpose of hardening. An inductor head is equipper with an aligning device designed as a spreadable cage which is equipped on the outside with clamping bars, clamping bosses a clamping shells which can be applied free from play and under the effect of force against the inner surface of the cylinder liner. The inductor loop is also displaced radially and brought into the working position by means of these clamping shells. Heating and hardening is carried out only with the inductor head in the clamped and exactly aligned state, whereas, after the clamping shells and the inductor loops have been released, a further indexed movement of the inductor head is possible. The work is carried out at relatively high alternating-current frequencies in the range between 400 and 500 kHz and at relatively high energy densities in the range above 5 kw/cm.sup.2 .

Abstract: An induction-hardening machine for the contour hardening of cross-axis, intersecting-axis and nonintersecting-axis gears such as hypoid gears includes a programmable logic control unit, a source of quench liquid and a high-frequency induction generator which are operably connected to a high-frequency induction coil which is disposed at an inclined angle above the horizontally disposed workpiece (hypoid gear). Fluid connections are made between the source of quench liquid and the induction coil for the rapid delivery of quench liquid. The support platform for the hypoid gear is connected to a rotary drive motor and with the hypoid gear rotating at approximately 900 to 1800 RPM the induction coil is energized with four low energy pulses of relativley short duration. The final heating step is a high energy pulse followed immediately by the quenching step.

Abstract: A method and apparatus for induction heating and quench hardening of an undulating cylindrical surface, such as that defined by gear or sprocket teeth, provide a hardness pattern uniformly distributed to a controlled depth across and between the teeth surfaces by means of axial scanning of the workpiece relative to a single induction heating coil. A distinct final heating scanning process follows a preheating scanning process whereby preheating and final heating can be conducted at differing controlled axial velocities. Axial scanning of the workpiece repeatedly past a single inductor coil enables preheating and final heating of workpieces which cannot be axially shifted directly between separate inductor coils, such as internal planetary ring gears having a closed end or external gears having a flange or shoulder protruding radially from the cylindrical gear teeth surface.

Abstract: An induction-hardening machine for the contour hardening of machine components such as gears includes a machine with both high-frequency and low-frequency induction generators operably arranged with corresponding induction coils positioned at a machine workstation and interfacing with computer controls. The high-frequency and low-frequency coils are arranged in a substantially concentric fashion such that the part to be induction hardened may be moved axially from one induction coil to the other depending upon the selected induction hardening process. The computer controls include a microprocessor operable to receive a computer disk which is formatted with specific machine settings and parameters for the automatic running and induction hardening of the particular part.

Abstract: An apparatus for hardening the outwardly facing teeth surfaces of a gear is disclosed. First and second induction heating coils with power sources controlled by an appropriate microprocessor heat the gear when in the first coil at a precisely controlled cycle to generate an unstable, circular band of high temperature positioned radially inwardly from the tips of the gear. Before the band can dissipate, the microprocessor actuates an appropriate drive to locate the gear in the second coil energized by an appropriate power source to impart a high skin temperature to the teeth. A liquid spray quench in the second coil is immediately actuated to effectively quench the gear. By sizing the cycles, the apparatus is thus able to rapidly harden the gear teeth at minimal power levels.

Abstract: A method and apparatus for progressively hardening an elongated workpiece having an outer generally cylindrical surface concentric with the central axis including the concept of providing closely spaced first and second induction heating coils each having workpiece receiving openings generally concentric with the axis of the workpiece; energizing the first coil with a low frequency such as a frequency less than about 50 KHz; energizing the second coil with a high radio frequency, such as the frequency exceeding 100 KHz; causing relatively axial and progessive motion between the workpiece and the first and second closely spaced coils in a direction entering the first coil and exiting the second coil whereby the cylindrical surface is progressively first preheated by the first coil and then immediately final heated by the second coil; and, then immediately quenching the cylindrical surface as it passes from the second coil whereby the cylindrical surface is progressively preheated, heated and quench hardened as

Abstract: A method of hardening the radially, outwardly facing surfaces of a generally circular, toothed workpiece adapted to rotate about a central axis generally concentric with the outwardly facing surfaces whereby the extremities of the surfaces define an outer circle by the tips of the teeth of the workpiece. This type of workpiece is generally a gear.

Abstract: A camshaft heat treating apparatus for processing a plurality of camshaft designs, which camshaft identifies and thereafter automatically inductively heats, quenches and inspects the camshaft in accordance with its design parameters.

Abstract: A method and an apparatus for the heat treatment of a workpiece, particularly an outer race member of a universal joint, having a cavity formed therein. The apparatus includes a horizontally disposed base and at least one elongated vertically disposed post extending upwardly therefrom with a passage extending at least partially longitudinally therethrough. The workpiece is mounted on the elongated vertically disposed post by insertion of the upper end of the elongated vertically disposed post into the cavity, the passage providing a venting of the cavity during the heat treatment operation.

Abstract: An inductor for heating the circumferentially opposed working surfaces and the root surface between adjacent gear teeth includes a nose portion received between the adjacent teeth and having a profile corresponding to that of the working and root surfaces. The nose portion is comprised of a flux concentrator having axially opposite ends and radially inner and outer ends, a generally V-shaped conductor plate having ends attached to the radial inner end of the concentrator and defining a coolant passageway therewith, and tubular conductors at the axially opposite ends of the flux concentrator and plate to provide for the circulation of coolant through the nose portion. A portion of the tubular conductor extends axially adjacent the radially outer side of the flux concentrator.

Abstract: An induction heating unit is disclosed which is operable to inductively heat and harden teeth on circumferentially extending radially thin flange segments of a gear. The unit includes an inductor conforming in circumferential contour and length to the flange segment and having radially and axially offset conductor leg portions to control heating of the gear teeth during relative axial scanning movement between the gear and inductor so as to prevent distortion of the gear flange. The unit further includes an arrangement for quenching the gear teeth and cooling the end portions of the flange segment during scanning movements.

Abstract: An apparatus for inductively hardening by quenching of the running surface of bearings of a crankshaft in which the crankshafts are transported by a lifter-conveyor system to a clamp which grips the crankshaft and is pivoted about a lever arm pivotably mounted on the machine frame to a heating position below a plurality of inductors. The inductors ride on the crankshaft as it rotates to inductively heat the running surfaces. The inductors are each mounted on a linkage which also mounts a quenching shower and the linkage in turn is swingably mounted on a further lever arm which is pivotably connected to the machine frame. As the crankshaft rotates, the inductor lifts and the further lever arm lifts off a stop. The apparatus preferably includes a second clamp and set of inductors to which the crankshaft is subsequently conveyed for further treatment after hardening.

Abstract: A device for inductively heating a cylindrical metal surface on an elongated workpiece having a central rotational axis, wherein the cylindrical surface is generally concentric with the axis. The device comprises an inductor having a generally cylindrical coupling surface matching the metal surface, a main support for carrying the inductor, the main support movable between a first position with the inductor spaced substantially from the cylindrical metal surface and a second position with the inductor in its heating position, and an intermediate frame for mounting the inductor onto the support.

Abstract: An apparatus for surface hardening an irregularly shaped workpiece made of hardenable material by inductive heating whereby a clamped workpiece is rotated past a linear conductor disposed along the envelope circle formed by the cam of the workpiece which extends farthest from the workpiece axis. The conductor has a plurality of yoke sheets to heat the workpiece surface uniformly.

Abstract: The invention is concerned with a horizontally closing die quenching apparatus and with a method for die quenching. The apparatus comprises a pair of relatively movable opposed substantially vertical platens each supporting a plurality of die blocks, the die blocks each having an internal cavity and generally opposed outer surfaces for receiving and substantially surrounding a plurality of first selected portions of a work piece when the platens are moved together. The die blocks also include a plurality of relatively small fluid passageways extending through the opposed surfaces thereof the passageways providing fluid communication with the cavities within the die blocks. A plurality of opposed fixtures are provided movable together relative to the platens for holding the work piece at its ends between the die blocks and means are provided for controllably pressuring the fixtures towards one another.