Abstract: The pressure medium used in the pressure chamber of a hydrostatic press is degassified in a degassing tank prior to delivery to the pressure chamber so as to improve the resistance of the pressure cylinder, or the liner inside of the pressure cylinder, to fatigue. The degassified pressure medium can be a mixture of recirculated pressure medium recovered after passage through the die extrusion hole and new pressure medium, such as castor oil.

Abstract: A multi-phase stirrer for stirring the molten cores of cast slabs from continuous casting machines is divided into at least two partial stirrers with each partial stirrer comprising at least one phase winding and fed with a number of phases at least one less than the total number of phases of the stirrer apparatus. Each partial stirrer may be arranged at different sides of the cast slab to form a rotary field around the cast slab in association with the other partial stirrers. Additional iron cores may be arranged in the air gaps formed between the iron cores of the respective partial stirrers. Alternatively, the additional iron cores may be arranged within the support tubes of the casting apparatus.

Abstract: An iron oxide melt reduction furnace has a hearth with a raised periphery forming an annular shelf, the hearth holding a carbonaceous iron melt up to a level forming a thin layer on the shelf. The furnace side wall extends upwardly from the periphery of the hearth's shelf, and means are provided for feeding material containing iron oxide to the melt at a location inside of the shelf, for reduction of the oxide by the melt's carbon. Means are provided for feeding solid steel scrap to the hearth's shelf and the shallow melt layer thereon so as to maintain on the shelf an annular pile of the scrap sloping downwardly from the furnace side wall to the inner periphery of the shelf.

Abstract: A tilting device for tilting crucible furnaces is supported in a stand wherein a yoke mounts the crucible furnace to the stand and is pivotable about a shaft extending transverse to the opening of the crucible furnace. The shaft is supported in movable guide tubes mounted within respective upstanding members of the stand. The movable guide tubes are releasably locked within the upstanding members such that operation of a lifting device causes the crucible and yoke to rotate about the shaft and release of the locking means causes the crucible and yoke to be lifted from the stand with operation of the lifting device and movement of the guide tubes within the upstanding members.

Abstract: A fluid-cooled thyristor valve including a plurality of series-connected thyristors that are cooled by non-conducting fluid flowing through electrically conducting cooling bodies positioned at the anode and cathode sides of the thyristors. The cooling bodies at opposite sides of adjacent thyristors are connected by fluid pipes that pass the cooling fluid. A plurality of electrically conducting sections of pipe connect the cooling body on the anode side and the cooling body on the cathode side of adjacent thyristors to pass the cooling fluid in one direction and to electrically connect the thyristors in series through the electrically conducting cooling bodies. A plurality of electrically insulated sections of pipe connects the cooling body on the cathode side and the cooling body on the anode side of adjacent thyristors to pass the cooling fluid in the opposite direction.

Abstract: Iron-chromium alloys, such as stainless steels, are made in a direct arc DC electric arc furnace with a bath of molten steel scrap in the hearth and functioning as the anode with the arcing electrode cathodic, while feeding chromium-oxide to the bath at the arc spot on the bath's surface under conditions causing reduction of the oxide and addition of chromium to the bath.

Abstract: Robot control with programmed positioning modified by a sensor sensing position error, force or the like. To maintain flexibility, the sensor axis need not coincide with any of several degrees of freedom of the robot. To employ sensor generated signals to modify programmed positioning where sensor and robot degrees of freedom are different, a normalized correction is computed relating a sensor output to each axis of freedom. Merely multiplying sensor output with the appropriate normalized correction provides a quantity in the proper coordinates for correction or position modification, as desired. Further, the robot includes apparatus to change direction of motion under certain circumstances, i.e., a collision with an obstruction. This allows the robot to move around obstructions whose location and extent were unknown at the time of movement programming.

Abstract: In a hydraulic press for forming sheet material, a vertically extending forming cavity is formed in a horizontally extending press stand between a pair of spaced forming pads extending between the inner surfaces of the press stand, and an elastically deformable member extends between the respective end of each of the forming pads for supporting the same. A tool carrier, with an upstanding tool support member having a tool forming depression on each side thereof on which sheet material is formed, is movable into and out of the forming cavity on respective support and guide rails which are engaged by respective support and guide rollers on the tool carrier. The tool carrier divides the forming cavity into a pressure seal on each side of the upstanding tool support member. A pressure medium is injected into each of the pressure cells to form the sheet metal.

Abstract: A capacitor bank for power factor correction and/or voltage control is connectible to an AC network through a bidirectional static switch. Voltage sensing and comparing means effect connection of the capacitor bank to the network at the moment when the instantaneous values of the mains and capacitor voltages coincide. During a predetermined time interval after disconnection of the capacitor bank from the network, the switch is periodically made conducting for keeping the capacitor charged with a voltage of constant polarity. After the end of this time interval, the switch is made non-conducting, whereby the capacitor is allowed to discharge through the discharge resistor.

Abstract: A DC arc furnace operation indicating system provides an indication and possibly a signal or control when during start-up the starting electrode does not make good electrical contact with a furnace charge of solid metal pieces and also thereafter when the shift is made to the melt electrode and it is not in a good electrical connection with the melt after the starting electrode is inactivated preparatory to the furnace going into normal production operation.

Abstract: Ferrous pellets are melted by feeding them to a ferrous melt in the hearth of an electric arc furnace having a centrally positioned arc. The melt is inductively stirred so that the lower portion of the melt flows radially outwardly while its upper portion flows radially inwardly towards the arc so that the pellets and possibly slag are carried towards the arc.

Abstract: In method for application of a tape of insulating material provided with a heat fixing binder to a substantially elongated rectangular electrical conductor in the longitudinal direction thereof, the conductor is heated, a portion of the tape is contacted with the first side of the conductor and other portions of the tape are successively contacted with other respective sides of the conductor. The successive steps of contacting after the first contacting step each include a first step of folding a portion of the tape about an edge of the conductor and then contacting a portion of the tape with a side of the conductor including that edge. The conductor may be additionally heated after several steps of folding and contacting, and pressure may be applied to the conductor and tape after the tape has been completely fixed to the conductor.

Abstract: A DC convertor for converting power at a particular input voltage level to a higher or a lower voltage level and operable despite changes in the direction of power flux between the input and output voltage levels. Main switching thyristors operate in conjunction with turn-off thyristors, a commutation capacitor, magnetically coupled inductor windings and bypass diodes to define the magnitude and direction of the flow of current in the convertor and the voltage conversion ratio of the convertor.

Abstract: This invention relates to a new and useful rotor assembly for an electrical device, such as a turbo-generator, and comprising; a core of magnetic material with at least one winding of a hollow conductor surrounding the core and rotatably supported by a pair of flanged end shafts, with a non-magnetic spacing piece positioned between the core and each of the flanged end shafts, and a prestressed cylindrical casing surrounding the core for retaining the coil winding in place against centrifugal force generated during operation of the rotor assembly.

Abstract: Disclosed is an elongated cylindrical furnace that includes a housing which defines an internal pressure chamber. An annular heater is disposed in the chamber in surrounding relationship to a centrally disposed material treatment space and an insulation layer is disposed in surrounding relationship to the heater. An annular gas impermeable wall is disposed in the chamber between the heater and the treatment space to isolate the latter from the space outside the wall where the heater is located. The outer heater space and the inner material treatment space are each provided with a respective source of pressurized gas for pressurization of the furnace to operating pressure.

Abstract: A system for transmitting signals between stationary and movable portions of a machine without utilizing any direct electrical contacts. An alternating supply source for the system is provided on the stationary portion and is connected to a stationary coupling member of an inductive coupling. A movable coupling member of the inductive coupling is arranged on the movable portion of the machine. A pulse generator connected to the movable coupling member receives its alternating supply voltage through the inductive coupling and generates a pulse during each period of the supply. A temperature dependent resistor controls the pulse generating device so that the phase portion of the pulse in relation to the zero passage of the supply voltage is dependent on the sensed temperature. The pulses are fed back through the inductive coupling to a measuring device arranged on the stationary portion of the machine.

Abstract: A method and apparatus for moving a device, such as a robot arm, through complex movements. The complex movement is divided into a principal movement between two defined end points A, B. Superposed on the principal movement is a closed loop series of subordinate movements (at least two subordinate movements) which loop is executed, at least once, during the principal movement. Data defining the end points of both principal and subordinate movements is stored in a storage device. Both principal and subordinate movements are divided into a number of equal incremental principal and subordinate movements. The sum of the principal and subordinate incremental movements is a composite incremental movement. Signals related to each composite incremental movement are provided to a drive means for moving the device.

Abstract: The circuitry for generating filter excitation signals from a multi-phase alternating current input is provided with the following circuitry for each phase of the multi-phase alternating current input. A current transformer connected to a respective phase of the multiphase alternating current input is connected to a bridge rectifier having one node connected to a neutral conductor and including a resistor of equal resistance value connected in each parallel branch of the bridge rectifier between the neutral conductor and the input of the current transformer. An operational amplifier having inputs respectively responsive to the voltage across each of the respective resistors in the bridge rectifier generates an output for one phase of the excitation signal to the filter. The filter excitation circuitry has application to two-phase and three-phase systems wherein the excitation circuitry is identical for each phase.

Abstract: An arc furnace has an arcing electrode through which a feeding passage is formed for feeding metal oxide particles through an arc and to a melt in the furnace. The arc is powered by DC power with the electrode cathodic and the melt anodic. Carbon is fed as required to reduce the oxides. Electric currents passing through the melt and the arc to the electrode are capable of causing magnetic forces forcing the arc to acquire an angular deflection in a downward direction away from alignment with the electrode's outer periphery and towards the side wall of the furnace in one direction subst antially continuously, during continuous operation of the furnace. Means are provided for electromagnetically causing the arc to continuously rotate, with its deflection, around the electrode.

Abstract: A DC arc furnace has a cathodic tubular graphite electrode forming an arc with an anodic carbonaceous iron melt in the furnace. A mixture of iron oxide and carbon particles is fed to the melt via the electrode's interior with the mixture's carbon content being in excess of that stoichiometrically required to reduce the iron oxide content of the mixture, the upper end of the electrode's feeding passage being blocked so that furnace gases cannot flow upwardly and impede the mixture's downward feeding flow.