Abstract: An electrochemical apparatus with a table formed by three slabs on which the workpiece rests. The table is mounted for rotation about a vertical axis and rests on a fixed support. A plurality of rollers in recesses of the fixed support engage the undersurface of the lower slab, and can be raised by servomotors to rotate the table. A clamping arrangement also engages the lower slab and fixed support for clamping the table in any desired orientation.

Abstract: A circuit and process for disconnecting the current from the operating gap of an electrolytic processing device in the event of a short circuit in which a signal is produced from the AC current in the transformer supplying power to the gap, such signal indicating the gap current, the maximum value of that signal is stored for successive time periods and the stored value for a preceding period compared with the present signal to operate a switch in the current supply to the gap when a short circuit condition is detected.

Abstract: A method and apparatus for electrolytic processing of a metallic workpiece in which short circuits in the operating gap which produce an arc are detected and extinguished by an auxiliary d.c. current of limited duration and counter to the direction of flow of the operating current without withdrawing the electrode or cutting off the operating current.

Abstract: An apparatus for tempering the surfaces of mutually displaced cams of a cast-iron camshaft in which heat energy sources are movably disposed at a distance from each cam. The apparatus holds the camshaft to be tempered in a vertical orientation for rotation about its axis and the heat sources are positioned about the camshaft axis at relative angles of rotation equal to the relative angles of rotation of the corresponding cams so that the cams may be heated simultaneously and syncronously with the rotation of the camshaft.

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 process in which pipes, particularly thick walled pipes, are inductively heated to the austenization temperature, quenched with a coolant to form martensite in the surface zone, then drawn, with additional heat added when necessary and left to cool with the not-quenched layers forming an interstage structure.

Abstract: A furnace for the inductive heating of metallic workpieces with an induction coil body encompassing a furnace space through which workpieces on receivers are transported. The receivers are a pair of hollow tubes extending in parallel through the furnace space for receiving workpieces, the tubes being reciprocally moved backwards and forwards. A pair of rods having cam surfaces thereon extend through the space below the tubes so that rotation of the rods lifts the workpieces off the tubes during backwards movement.

Abstract: A machine for simultaneously electrochemical processing a plurality of workpieces in which a workpiece receiver is mounted on spring loaded rails between a clamping unit and a base for horizontal movement between loading and operating positions. A working electrode extends through a bore in the clamping unit to create a working gap with a workpiece which is electrically connected via a spring loaded contact member to a source of eroding current. The clamping unit can be moved up and down to make and break electrical contact and to clamp and release the workpieces. Electrolyte is supplied to and removed from the working gap.

Abstract: A shearing apparatus in which heated metal is transported to a shearing position, clamped and sheared. After clamping, a force is applied along the longitudinal direction of the bars and, if movement is detected, the incorrectly dimensioned bar is discarded.

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: An electromagnetic conveying trough for conveying molten metals with a trough body extending in the direction of conveyance and lined with a fireproof lining and an inductor for producing a travelling electromagnetic field and formed as a grooved laminated package, the transversely extending grooves defining teeth about which individual coil windings are wrapped. In order to replace the inductor below a molten metal breakthrough without removing all of the lining, the coolant pipes are formed coaxial with each winding as a unit with separate coolant connections to each such unit.

Abstract: A system for induction heating of workpieces which are transported touching or in close proximity through a succession of inductor coils along the workpiece axes. A grounded feeder supplies workpieces to the transporting structure and a grounded further processing machine receives the workpieces after heating. To eliminate sparking and corrosion problems, the AC currents fed to the coils are adjusted, for example by feeding currents in phase opposition to different coils, so that the potential along the direction of the workpieces from the first to last coil is substantially zero.

Abstract: A continuous heating induction furnace in which workpieces are mounted on a receiver for step-wise movement from a furnace inlet to outlet through a longitudinally extending chamber. A pair of lifter rods extend through bores at the chamber floor to engage the workpieces at each of a plurality of stops or stations and are in turn rigidly connected to a bar element extending below the chamber. The receiver reciprocates along the longitudinal direction while the lifter rods elevate the workpieces during backward receiver movement. The receiver is formed as a pair of tubes which engage bearings mounted at separated locations along the chamber so that the length of the chamber is not limited by the sag characteristics of the receiver.

Abstract: A bridge circuit of the type whereby a plurality of individual switching elements such as thyristors are mounted in a frame between four contact rails. To minimize interaction between current flow in the elements and to cause the load current to be divided roughly evenly over the elements, the elements are physically mounted between the rails so that adjacent parallel mounted elements belong to different arms and do not carry current at the same time.

Abstract: The invention is an improved detector system for determining and indicating the level of a molten charge within a furnace. The system can determine the level of the charge without the need for having contacts or other sensing devices within the furnace by sensing impedance changes in the furnace's heating coils.

Abstract: An electrical conductor of the type having a central cavity which extends along the longitudinal axis of the conductor to conduct refrigerating fluid which cools the conductor heated by high current density current flow whereby, to increase thermal efficiency and decrease deposits on the walls of the cavity which reduce the lifetime of the conductor, the cavity walls have non-smooth undulations, forming for example isosceles triangles.

Abstract: A method for producing a welded and quench hardened steel pipe and pipe whereby the weld seam running spirally or longitudinally along the pipe length has a lower austenization temperature than the pipe and/or a higher electrical resistance. The ratio of the pipe to seam resistance is preferably greater than one half and the whole of the square of the ratio between pipe wall thickness and mean seam thickness. The seam preferably includes amounts of C, Si, and Mn in the same percentage as the pipe plus nickel between 2-6%.

Abstract: Apparatus for inductive hardening of the bearings of crankshafts by a rotational process, wherein various parts of the surface of the workpieces are heated by variably shaped inductors, and wherein the workpiece is loaded horizontally with a hardening carriage, which supports a transformer plate for supporting a transformer connected to a medium frequency current source and an inductor attached to the transformer plate, and an automatic control to move the transformer plate to load and unload separate inductors for treating variably shaped workpiece surfaces.

Abstract: An improved hardening apparatus of the type having a main carrier shaft which mounts pairs of indexing spiders which hold workpieces during treatment which includes quenching in a bath. The shaft is developed hollow and provided with a spur gear near one end which functions as a sunwheel of planetary gears. The hollow shaft is provided with perforations in the area of the spur gear through which it extends to engage the tailstock gear which is flanged to the housing surrounding the shaft.

Abstract: An improved parallel-resonant circuit inverter of the type having a rectifier, a thyristor DC/AC converter connected thereto and operating at a controllable frequency, a parallel resonant circuit with an inductive load and a method of operation of such circuit whereby the converter voltage U is maintained at a constant operating value U.sub.B for a constant DC current I.sub.g = I.sub.go, in a first control range characterized by a low resonant-circuit damping, and control of the direct current I.sub.g for the purpose of maintaining the DC/AC voltage constant at its operating value U.sub.B, in the case of a constant thyristor extinction time t.sub.L = t.sub.LO, in a second control range characterized by a high damping, as well as by transition from the first to the second control range, if t.sub.L becomes equal to t.sub.LO in the case of increasing resonant-circuit damping, and transition from the second to the first control range, if I.sub.g become equal to I.sub.go in the case of decreasing damping.