Abstract: A system and method for inductively heating a workpiece includes a controller and a plurality of power supplies that receive and send signals to the controller. Induction heads receive power from the power supplies. The induction heads may be aligned with adjacent segments of the workpiece, and can span the perimeter of the workpiece. The gap between adjacent induction heads is less than one half the size of the adjacent induction heads, and preferably the induction heads abut or substantially abut. Each of the power supplies include feedback for controlling the power delivered to the segments of the workpiece. In alternative embodiments the feedback may be based on the current or power provided to the induction heads, or the power provided to the workpiece.

Abstract: A structure and method are disclosed which allow for a tighter control of the temperature across a wafer substrate. In accordance with the present invention, a wafer to be processed is heated to a constant and uniform temperature by an RF induction coil including a plurality of heating zones each of which being shunted by an associated capacitor tuned to a specific frequency. By adjusting the time during which current of a particular frequency is provided to the induction coil, current flow within, and thus the heat generated in, each of the zones may be independently controlled. Since the heat generated in the susceptor quickly changes in response to changes in current flow therein, both deviations of the wafer temperature from the processing temperature and temperature gradients across the surface of the wafer may be quickly corrected. This superior thermal response results in the present invention maintaining a wafer at a uniform temperature during heating and cooling with increased accuracy and precision.

Abstract: An induction heating method and apparatus for simultaneously and efficiently fusing battery cell terminal posts and bushings in a battery production line. The apparatus includes an induction heating generator having a T-shaped bus bar for symmetrically supporting a plurality of pairs of induction heating coils, with one coil of each pair being supported on the forward side of a transverse bus bar section and the other coil of each pair being supported on a rear side of the transverse bus bar section. The coils each have respective mounting structures for permitting individual vertical adjustment of the coil with respect to the bus bar to enable uniform positioning of the coils with respect to a plurality of bushings and terminal posts for effecting uniform depth fusion of the plurality of posts and bushings.

Abstract: A method and hot rolling apparatus for producing a hot rolled steel sheet include a roughing rolling mill to roughing roll a heated slab into a sheet bar, at least one solenoid-type induction heater arranged for re-heating the sheet bar over its entire width, and a finish rolling mill arranged to finish roll the re-heated sheet bar into a hot rolled steel sheet having a predetermined thickness. An initial temperature before rolling is set to be low, and re-heating of the sheet bar is carried out around the middle of the hot rolling apparatus. The thermal energy required for rolling is thereby reduced as a whole without damaging the quality of the resulting hot rolled steel sheet. A descaling apparatus is provided prior to the finish rolling mill to remove oxide scales on surfaces of the sheet bar, whereby the resulting hot rolled steel sheet is free of scale flaws and exhibits superior surface properties.

Abstract: A method of joining or welding of at least a portion of a first metal workpiece to at least a portion of one or more second metal workpieces, comprising inducing movement in said portion of the first workpiece by means of a pulsed magnetic force so as to impact said portion of the second workpiece, the movement imparting a kinetic energy on the at least portion of the first workpiece to cause the two at least portions to join or weld to one another.

Abstract: An induction heating generator is described for braze-welding metallic pipes with a continuous process under a controlled atmosphere, comprising at least one heating inductor composed of two half-inductors in series whose winding directions for their windings are one opposite to the other. The generator is further equipped with a quartz tube placed inside the inductors and in which the metallic pipes pass together with the controlled atmosphere gas. The generator further includes at least one removable sealing insert to join two contiguous inductors. For every medium- and/or high-frequency section of the generator, a load matching system is finally provided to compensate for external diameter variations of the pipes, the system being interlacedly handled by a programmable controller (P.L.C.).

Abstract: The steam generating system utilizing a first container having a liquid chamber. The first container is surrounded by a conducting coil for generating a field and producing eddy currents on the container. Steam produced in the first container is sent to a second container which is similarly heated by an induced eddy current. Steam in the second container is superheated for use.

Abstract: A heating system and method for heating a metal strip to within a predetermined temperature tolerance range while the metal strip serially travels through a heating system. The heating system has at least one preceding heating section, at least one induction heating section, and at least one following heating sections, with the heating sections being serially arranged. The metal strip is heated to below the Curie point of the metal strip in the preceding heating section. Next, the metal strip is heated to, at a maximum, approximately the Curie point in the induction heating section. Then, the metal strip is heated to above the Curie point and to within the predetermined temperature tolerance range in the following heating section.

Abstract: An H-field electromagnetic heating system for fusion bonding, particularly useful in the sealing of telecommunications cables and closures, comprises a composite bonding material having a bonding matrix and susceptors, the susceptors being magnetically reactive at a frequency above 50 MHz, and an applicator for applying radiant electromagnetic energy to the composite bonding material, at a frequency above 50 MHz (preferably 75-500 MHz). The applicator may take the form of a quarter-wave resonator having an inner conductor and an outer conductor which at least partially surrounds the inner conductor, the two conductors being shorted at a common end. The material to be heated is placed between the conductors. The inner conductor may include a resonator tube which is capacitively coupled to the power supply by a capacitive probe connected to the center conductor of a coaxial connector.

Abstract: A method and apparatus in which edge portions of metal parts, the edge portions being disposed with opposed surfaces, are heated by high frequency electrical currents as the edge portions are advanced and brought together at a weld point. The electrical currents are induced in the edge portions in advance of the weld point by two induction coils, one at one side of the metal parts and the other at the other side of the metal parts, disposed and energized from a high frequency electrical source so that the electrical currents at the opposed surfaces flow in opposite directions at any given time and the currents induced by one coil add to the currents induced by the other coil.

Abstract: Apparatus and method of induction heating wherein the heating operation is conducted in a low oxygen-containing atmosphere by the introduction of an inert gas alone or in combination with an oxygen-reacting gas through the ends of the induction coil housing or through removable covers enclosing the spaces between spaced apart housings.

Abstract: Disclosed is a high-frequency heating apparatus including an elongated chamber in which a plurality of rocker arms are introduced, each of the rocker arms being attached with a chip and brazing filler such as a copper wax, a high-frequency brazing coil for high-frequency heating a designated part of each rocker arm in the chamber to braze the chip to the rocker arm, a high-frequency temperature-holding coil for holding the temperature of the rocker arm constant, and a nitrogen gas supplying device for keeping the chamber filled with a nitrogenous atmosphere during the high-frequency heating.

Abstract: A method and a system for heat treating an impact beam of an automotive vehicle door. Hot rolled steel sheets are prepared having a composition consisting essentially of 0.18% to 0.22% carbon; 1.0 to 1.5% manganese; 0.15 to 0.4% silicon; not more than 0.025% phosphorous; not more than 0.008% nitrogen; not more than 0.0010% sulfur; 0.01 to 0.04 aluminum; 0.001 to 0.003% boron; 0.1 to 0.3% chromium; 0.01 to 0.035% titanium; and the balance essentially iron, roll-forming and welding the steel sheets to make a tube-shaped impact beam. The heat treatment is carried out by high frequency induction heating and air cooling the impact beam, and water cooling the heat treated and air cooled impact beam.

Abstract: An induction coil is passed over an interface between two resinous parts to be welded and an alternating magnetic field generated by the coil induces eddy currents in a foraminous susceptor positioned in the interface between the two parts. Pressure is applied to squeeze the two parts together while the induction heating of the susceptor raises the temperature of the resin in the faying surfaces of the two parts to the softening temperature so that resin flows through the interstices in the susceptor and bonds the two parts together. The induction heating and pressure application passes are repeated four or more times, increasing the power to the induction coil in the later passes to increase the heat input. The strength and continuity of the weld improves with each pass, although the incremental improvement diminishes after about four passes.

Abstract: In a billet induction heating device, a plurality of heating coil units having round holes different in diameter from one another are arranged in such a manner that the central axial lines of the round holes are in parallel with one another and are in a vertical plane, and moving means supports the heating coil units thus arranged. Whenever a billet is given which is different in size from the one which has been processed, among from the heating coil units one suitable for the given billet is selected, and the moving means is operated to move the heating coil units until the selected heating coil unit reaches the position where it can accommodate the given billet. This arrangement makes it possible to achieve the replacement of the heating coil unit quickly and readily.

Abstract: An asymmetric coil which has an "A" winding on one pole of the "C" core and a "B" winding of opposite helical twist, on the other pole, we can achieve relatively uniform, intense heating between the poles with relatively insignificant heating outside the poles. Only one core winding is active at one time. This coil allows us to heat uniformly to the ends of the susceptors on the ribs without remelting or overheating the welded area under the abutting spar, as FIG. 6 illustrates. The asymmetry provided by the two windings of opposite helical sense and the core design allows us to travel in either direction by activating the appropriate coil.

Abstract: Disclosed is a high-frequency heating apparatus including an elongated chamber in which a plurality of rocker arms are introduced, each of the rocker arms being attached with a chip and brazing filler such as a copper wax, a high-frequency brazing coil for high-frequency heating a designated part of each rocker arm in the chamber to braze the chip to the rocker arm, a high-frequency temperature-holding coil for holding the temperature of the rocker arm constant, and a nitrogen gas supplying device for keeping the chamber filled with a nitrogenous atmosphere during the high-frequency heating.

Abstract: An apparatus includes (a) a device which is capable of selectively generating heat in electrically-conductive material without substantially generating heat in non-electrically-conductive material, (b) a device capable of heating non-electrically-conductive material, and (c) an insulating shield between the two devices to help focus the energy generated by at least one of the devices.

Abstract: A method of case hardening a steering gear rack bar having a plain cylindrical barrel portion and an integral toothed portion on which are formed a plurality of rack gear teeth each having a predetermined helix angle relative to a longitudinal centerline of the rack bar. The method includes forming an induction coil having a linear section and a spiral section with a helix angle equal to the helix angle of the rack gear teeth, locating the rack bar inside the induction coil with the barrel portion thereof juxtaposed the linear section of the induction coil and with the spiral section of the induction coil surrounding the toothed portion, rotating the rack bar about its longitudinal centerline while passing alternating electric current through the coil to concurrently induction heat both the barrel portion and the toothed portion, and quenching the rack bar after the alternating current is turned off.

Abstract: The product (11) is in relative motion in the direction (12) of its axis with respect to at least one magnetic inductor (10, 10'). The metallurgical product (11) is subjected to at least two magnetic fluxes (19, 19') having non-parallel directions which are transverse with respect to the longitudinal direction of the product (11). The heating device may advantageously consist of two C-shaped magnetic yokes (14, 14') spaced apart and angularly offset along the axial direction (12) of advance of the product (11).

Abstract: Transverse flux heating assembly for inductively heating a moving strip includes opposite spaced J-shaped conductors to form an inductive heating coil. The coils define a middle spacing therebetween which is unobstructed by flux guides to permit free translation movement between the conductors in a direction parallel to the strip width. The inductors provide a fully adjustable coil width to accommodate different strip widths in the heating operation.

Abstract: An apparatus for the inductive cross-field heating of flat material includes a plurality of mutually opposite induction loops being disposed above and below the flat material. At least one pair of induction modules is formed of two induction modules being adjustable independently of one another in their position relative to the flat material. Each induction module has two mutually opposite U-shaped induction loops having geometries and dimensions which are invariable, base legs which can be positioned in such a way that they terminate at least a predeterminable distance in front of one edge of the flat material and within the width of the flat material, and two side legs which can be positioned in such a way that they project at least a predeterminable distance beyond the other edge of the flat material.

Abstract: Induction heating apparatus, typically for metal melting, with multiple zone temperature control has an induction coil (10) divided into individual sections (10a, b, c) associated with respective zones and powered in parallel under regulation from controller (20) as shown in FIG. 1. To give precise and efficient automatic regulation of the zone temperatures the power supply is provided by a resonant invertor (14) as a medium frequency pulsed output and at an instantaneously selected level which is the sum of the power requirements of all the zones at any instant, and the average power applied in each zone is controlled by pulse width modulation with switching to high power for a proportion, determined by demand in that zone, of each of successive standard time periods.

Abstract: A method and apparatus are disclosed for the continuous annealing of amorphous metal cores of the type used in electrical transformers, and wherein the cores are heated in the presence of a magnetic field. The cores are transported serially along the length of a stationary electrically conductive rod which is located within a furnace, and such that the central openings of the cores face horizontally and the rod passes through the central openings of the advancing cores. Electrical current is caused to flow through a closed loop which includes the rod so as to generate an electromagnetic field along the length of the rod and so that the cores pass through the field while being heated.