Abstract: An induction coil assembly includes an annular member extending from a first end to a second end, and extending about a longitudinal axis; a first leg extending from the first end of the annular member, and including a first electrical connection portion and a first axial portion; and a second leg extending from the second end of the annular member, and including a second electrical connection portion and a second axial portion. An internal surface of the annular member defines a first fluid passage through the annular member. An internal surface of the first leg defines a second fluid passage through the first leg. An internal surface of the second leg defines a third fluid passage through the second leg. The second fluid passage is in fluid communication with the third fluid passage via the first fluid passage.

Abstract: An induction coil with inner and outer coil segments joined together by a transition segment is arranged so that the outer coil segment generally inductively heat treats an annular outer region of a workpiece positioned under the coil, the inner coil segment generally inductively heat treats an annular inner region of the workpiece, and the transition segment traverses at least a portion of the width of the overall annular region of the workpiece to be heat treated. Relative arrangement of inner, outer and transition coil segments provides for controlled induction heat treatment across the overall annular region such as the gear teeth region of an intersecting axes or non-intersecting and non-parallel axes gear.

Abstract: Disclosed herein are a tripod joint spider, a method of manufacturing the same, and an alloy steel of the tripod joint spider. The method comprises producing a primary molded article using the alloy steel, producing a secondary molded article, hardening the secondary molded article by means of induction hardening, and producing an end product.

Abstract: A tool system for stress relieving a turbocharger turbine wheel longitudinally welded to a hardened rotor shaft. The shaft has a journal bearing region and a turbine-end body forming an A datum surface for receiving an axial bearing. The tool system includes an induction coil and an electronic oscillator, and a tool. The tool forms an opening configured to receive the rotor shaft such that the journal bearing region of the shaft extends into the tool housing while the A datum surface adjoins an end of the tool housing. The induction coil is positioned around the turbine-end body. The housing forms an annular cooling chamber surrounding the journal bearing region of the shaft. The housing forms an inlet passage to provide cooling fluid to the annular chamber, and an outlet passage to remove cooling fluid from the annular chamber.

Abstract: A method and system are disclosed for treating a press hardened part by induction heating localized areas of the part to have reduced hardness. The method and system monitor an ambient temperature, cycle time, outgoing part property requirements, and outgoing part hardness in local areas. A time value and temperature value are set by a computer system for a plurality of induction heaters. A local area of the part is induction heated to soften the part in localized areas. The hardness of the localized areas is tested after induction heating.

Abstract: A process for treating a steel alloy component includes the steps of: providing a steel alloy component having a plurality of teeth with a root portion and a tip; and processing the steel alloy so that the root portion of the gear teeth are hardened without through hardening of the tips of the gear teeth.

Abstract: Apparatus and method are provided for inductively heating workpieces with varying characteristics in the same induction coil while selectively controlling the induced heat temperature distribution profile of each workpiece with one or more flux compensators inserted into the induction coil along with the workpiece to be inductively heated.

Abstract: The present invention relates to an induction hob with a cooking surface (10) and a number of induction coils (12; 16, 18) within said cooking surface (10). The induction coils (12; 16, 18) are arranged on the cooking surface (10) according to predetermined scheme, so that at least two induction coils (12; 16, 18) can be covered by a standard cooking vessel (14). Each induction coil (12; 16, 18) is connected to at least one induction generator being switched or switchable between a high power and a low power. Each induction generator is separately controllable, so that the induction coils (12; 16, 18) are switched or switchable between the high power and the low power. At least one control unit is provided for controlling the individual induction coils (12; 16, 18) according to a predetermined time pattern. Further, the present invention relates to a corresponding method for controlling the induction hob.

Abstract: A system and method of induction heat treating a gear includes a workstation. The workstation has a power source, an inductor coil, and a rotational mechanism. The gear is induction heat treated at a first portion of the gear and a second portion of the gear remains untreated by induction hardening. The gear has an inner surface. The inner surface includes the first portion and the second portion. The first portion has a first width. The second portion has a second width. The inductor coil includes at least one heating loop and at least one non-heating loop. The inductor coil is energized to a predetermined frequency to create an alternating magnetic field, where the alternating magnetic field developed in the heating loop induces an eddy current in the first portion of the gear.

Abstract: In a method for manufacturing a gearwheel, a gearwheel blank is clamped in a workholder of a multi-axis machine tool. A milling head is clamped in a tool holder which is rotated by a spindle drive to enable the milling head to mill out tooth spaces of the gearwheel blank to thereby create a gearwheel having teeth. After replacing the milling head in the tool holder with an inductor, the inductor is inserted successively between two adjacent teeth of the gearwheel and supplied with alternating current from a current supply device of the spindle drive to inductively heat at least one of the two adjacent teeth. The inductor in the tool holder is then replaced with a machining tool to remachine the teeth of the gearwheel.

Abstract: A method and device for heating or hardening at least an axial segment of a rotationally-symmetric surface of a work piece includes rotating the work piece about its rotational axis and moving a peripheral portion of an inductor along a longitudinal profile of the axial segment of the rotating work piece with a constant spacing between the peripheral portion and the axial segment. At least a portion of the movement of the peripheral portion is composed of a first vector component in the direction of the rotational axis and a second component extending perpendicularly to the first vector component. The peripheral portion has a length in the rotational axis direction that is less the length of the axial segment in the rotational axis direction.

Abstract: A device for hardening the teeth (2) of gear wheels by inductive heat treatment provides for at least two hardness inductors (3), which are distributed over the circumference.

Abstract: A method of manufacturing a mechanical component made of steel including a surface-hardening phase. The method includes creating a rough form of the component with regions to be hardened, then successive case hardening with cooling without quenching, heating to an austenitizing temperature of the steel by induction heating the zones, and quenching.

Abstract: A system and method of induction heat treating a gear includes a workstation. The workstation has a power source, an inductor coil, and a rotational mechanism. The gear is induction heat treated at a first portion of the gear and a second portion of the gear remains untreated by induction hardening. The gear has an inner surface. The inner surface includes the first portion and the second portion. The first portion has a first width. The second portion has a second width. The inductor coil includes at least one heating loop and at least one non-heating loop. The inductor coil is energized to a predetermined frequency to create an alternating magnetic field, where the alternating magnetic field developed in the heating loop induces an eddy current in the first portion of the gear.

Abstract: A system and method of induction heat treating a gear includes a workstation. The workstation has a power source, an inductor coil, and a rotational mechanism. The gear is induction heat treated at a first portion of the gear and a second portion of the gear remains untreated by induction hardening. The gear has an inner surface. The inner surface includes the first portion and the second portion. The first portion has a first width. The second portion has a second width. The inductor coil includes at least one heating loop and at least one non-heating loop. The inductor coil is energized to a predetermined frequency to create an alternating magnetic field, where the alternating magnetic field developed in the heating loop induces an eddy current in the first portion of the gear.

Abstract: A gear part has a quench hardened layer around the teeth surface thereof. The gear part is made of a steel containing carbon of 0.43 to 1.2 wt %, and a relationship between a DI value and a module M (mm) of the gear part satisfies an expression of DI?0.12×M+0.2. An alloy element concentrates in the cementite phase in a pretreated steel, thereby causing concentration of the alloy element in the ferrite phase in the pretreated steel to decrease, and a rapid induction heating to A3 transformation temperature or Acm transformation temperature causes carbon of 0.3 to 0.8 wt % to diffuse and dissolve in the austenite phase, and the DI value is determined by using a concentration of the alloy element and a concentration of the carbon. The alloy element is one or more elements selected from the group consisting of Mn, Cr, Mo, V and the like.

Abstract: A method is provided for producing a bearing ring (1) for large-size rolling bearings including at least one track (3) that is provided with a hardened peripheral layer. With the method the peripheral layer that is to be hardened is exposed to the electric field of an inductor in order to be heated and is then quenched. At least two inductors (2) are disposed above a common zone (a) of the annular track (3) that is to be hardened at the beginning of the hardening process. These inductors (2) heat the opposite peripheral layer to a hardening temperature at this location. The inductors (2) are moved in the opposite direction along the annular track in order to heat the adjacent central zones (b). Sprinklers (5) that are directed onto the heated peripheral layers are turned on following a short distance, and the peripheral layers are quenched starting from the center of the zone (a) that was heated at the beginning.

Abstract: A system and method of induction heat treating a gear includes a workstation. The workstation has a power source, an inductor coil, and a rotational mechanism. The gear is induction heat treated at a first portion of the gear and a second portion of the gear remains untreated by induction hardening. The gear has an inner surface. The inner surface includes the first portion and the second portion. The first portion has a first width. The second portion has a second width. The inductor coil includes at least one heating loop and at least one non-heating loop. The inductor coil is energized to a predetermined frequency to create an alternating magnetic field, where the alternating magnetic field developed in the heating loop induces an eddy current in the first portion of the gear.

Abstract: An apparatus (1) for heat treating the surfaces (32b) of gear teeth (32a) via magnetic inductive heating comprises a magnet assembly (40) and a workpiece (or gear) holder (30) operatively mounted on a base (12). The magnet assembly (40) is rotatable in a first plane about a first axis (A1), and the work-piece holder (30) (on which a gear (32) can be removably mounted) is rotatable about a second axis (A2) in a second plane. The first and second axes (A1, A2) are spaced apart from each other and the first and second planes intersect each other.

Abstract: A device for hardening the teeth (2) of gear wheels by inductive heat treatment provides for at least two hardness inductors (3), which are distributed over the circumference.

Abstract: An induction coil with inner and outer coil segments joined together by a transition segment is arranged so that the outer coil segment generally inductively heat treats an annular outer region of a workpiece positioned under the coil, the inner coil segment generally inductively heat treats an annular inner region of the workpiece, and the transition segment traverses at least a portion of the width of the overall annular region of the workpiece to be heat treated. Relative arrangement of inner, outer and transition coil segments provides for controlled induction heat treatment across the overall annular region such as the gear teeth region of an intersecting axes or non-intersecting and non-parallel axes gear.

Abstract: A thermal quenching installation making use of induction heating. This installation has induction heater means comprising a stationary induction coil, handling means to cause the element to pass through said coil, and cooling means, preferably a shower, disposed downstream from the coil.

Abstract: An apparatus and process are provided for multi-frequency induction heat treatment of workpieces including gears. High frequency power is applied to an induction coil that surrounds the workpiece so that a high frequency magnetic field couples with the workpiece to inductively heat the workpiece. A C-core inductor is coupled to a coil that has low frequency power applied to it. The workpiece is inserted in a gap in the C-core inductor magnetic circuit so that it experiences low frequency Joule effect heating when the low frequency current is applied to the coil coupled with the C-core inductor. Alternatively the workpiece may be inserted around the C-core inductor when the workpiece has an opening.

Abstract: The induction coil of a device that heats a toolholder (1) inductively for the tool change comprises a shielding collar (27) of magnetizable material which, firstly, concentrates the magnetic flux of the induction coil (13) in a sleeve section (5) of the toolholder (1) which holds the shaft (11) of a rotary tool with a press fit and, secondly, shields the part of the tool shaft (11) that projects out of the sleeve extension (5), in order to facilitate unclamping the tool from the toolholder (1). On its side facing the winding (19) of the induction coil (13) axially, the shielding collar (27) has an outer circumferential surface (31) which widens conically away from the sleeve extension (5) and an axial height (h) which is at least 1.5 times the diameter (d) of the tool shaft (11). The shielding collar (27) runs on all sides at a distance from a yoke shell (23) of magnetizable material which encases the winding (19) of the induction coil (13).

Abstract: The invention relates to a method for improving the mechanical properties, especially the hardness, of journal crosses for use in articulated shafts. According to the invention, a superficial area which is defined by the transition surfaces between two journals that are adjacent to each other in the peripheral direction and the superficial areas of the peripheral surfaces of the adjacent journals that point in the peripheral direction is induction-hardened in one method step and then quenched with cooling agents.

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.

Abstract: An apparatus and method to inductively heat beveled gear teeth. An inductor has an annular body with a plurality of projections for meshingly engaging beveled of the gear. An inductor coil or loop is associated with each of the projections and is at least partially disposed between successive gear teeth to induce a magnetic flux directly there through when engaging the beveled gear. By simply rotating the inductor relative to the beveled gear while simultaneously sending a current through the coil, successive gear teeth are treated. Preferably, the number of gear teeth differs from the number of projections, and the beveled gear is rotated sufficiently to ensure that each of the projections and associated coil engages each of the beveled gear teeth to facilitate a more uniform treatment.

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.

Abstract: An apparatus for hardening cylindrical bearing faces (L) of a shaft (K), wherein at least one of the transitional radii (R1, R2) to the adjoining shaft portions (W1, W2) is constructed recessed, includes a pair of inductive heating units (1, 2), which are each formed at least by one inductor (3, 4) having two spaced-out heating conductor branches (20, 22; 21, 23); an adjusting device (11, 12) for adjusting the inductors (3, 4) simultaneously from the radial direction (R) on to the bearing face (L) to be hardened and a second adjusting device (13, 14) for moving at least the inductor (3, 4) associated with the recessed radius R1, R2) after application to the bearing face (L) by a movement directed axis-parallel with the longitudinal axis (X) of the shaft (K) in the direction of the recessed transitional radius (R1, R2) until its outer heating conductor branch (20) has moved into the particular transitional radius (R1, R2).

Abstract: A method and apparatus for in-situ induction tempering is provided in which an induction coil is used to temper a part in-situ at the location. The use of an induction coil in-situ at the heat treating location eliminates the need (and time and expense) of a multi-step process wherein in part to be tempered would otherwise have to be moved from the quenching location to the tempering location, such as at a tempering furnace. It also eliminates the need for the tempering furnace, which is a great space savings. In one form of the invention, the power supplied to the induction coil is controlled by a closed-loop temperature controller that is controlled by the temperature in the vicinity of the tempered part, as opposed to simply be controlling on time at temperature.

Abstract: The invention relates to the rotary and simultaneous electroinductive hardening of the bearing surfaces (2a; 3a) of crank pins (2; 3) of a crankshaft (1) disposed immediately one beside the other and offset in relation to one another in the axial direction (D), having inductors (10; 11) which each engage around the crank pins (2; 3) by a maximum of 180.degree. and which each have two inductor branches (12, 13; 14, 15) arranged in parallel and following the curvature of the bearing surfaces (2a; 3a), of which one branch is associated with the overlapping zone (5) of the crank pins (2; 3), the other branch being associated with the particular other edge zone (2b; 3b) of the crank pin (2; 3) associated therewith, the inductor branches (12, 13; 14, 15) of each inductor (10; 11) having in the axial direction (D) a distance (A) increased in relation to half the total width (B) of the crank pins (2; 3).

Abstract: An induction heating device for surface treating the teeth (11) of a mechanical part on which each tooth (111) has a projecting tip (111s) and a tooth root linking the tooth to an adjacent tooth, wherein an in duction coil (12, 12') is spaced from the tooth tips and powered by at least one high-frequency current source. The coil consists of a set of conductive segments (24, 24') individually orthogonal to the generatrix (d, d') of the teeth, located above respective tooth tips and interconnected via connecting segments (25, 25').

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: 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: 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, in one embodiment, 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 relatively short duration. The final heating step is a high energy pulse followed immediately by the quenching step.