Abstract: A carbon electrode for use in an arc lamp used for determining light fastness which has a central core of light emitting material combined with stabilizers and graphite surrounded by a first coating of low resistance electrically conductive material, preferably copper or aluminum. The thus-coated core is further coated with a second coating of graphite and adhesive and inserted into a cylindrical carbon tube. The tube, except for the top and bottom portions is coated around the outside with a third protective coating, and the base and bottom portions of the tube are coated with a metallic coating electrically connected to the first coating of low resistance material spaced from the third coating. The third and fourth coatings may be joined together, provided that the resistance of these two coatings is greater than the resistance of the first coating.

Abstract: Nonconsumable electrode for melting metals and alloys, comprising a housing with a hollow fluid-cooled tip. On one of the tip's side-walls, on the side of the cavity, there is at least one threaded groove. This side wall with the threaded groove on it serves as a means for the rotation of the arc which is actuated between the tip and a metal or alloy to be melted.

Abstract: An electrical primary control system for furnaces and method of making the same, the system comprising burner control means, an isolated low voltage control circuit and means for interfacing between the isolated low voltage control circuit and the burner control means; the interfacing means including a pair of resilient, magnetic reeds disposed within a hermetically sealed envelope, and a pair of electrically insulated independently wound coils having a differential in ampere turns and encompassing the envelope, the magnetic flux generated by such coils being additive whereby energization of both of the coils is required to close the contacts but energization of one of the coils is sufficient to maintain the contacts closed, at least one of the coils having a resistance wire of predetermined calibrated resistance electrically connected in parallel circuit therewith.

Abstract: A process to form a positive electrode of an arc by joining two principal carbon-base electrodes and the product resulting therefrom. The two principal electrodes are axially perforated at one of their ends to tightly receive a small secondary electrode which fills the perforations. The small secondary electrode is a mixture of carbon and graphite covered with a copper layer. The material of the three electrodes is compatible so as to operate at an optimum temperature, amperage and color which are essentially the same for use in a cinematographic projector.

Abstract: The device of the invention comprises a hollow cooled rod on which a mass transmitter for a consumable electrode is secured. The casing of the mass transmitter accommodates two bellows of different diameter operating as a sensitive element interacting with an annular projection on a bar shifting along the axis of the bellows and acting as a movable element. The bellows are arranged one above the other along the bar axis, one end of each of the bellows being fixed on the annular projection and the other, on the casing. One bar end face is rigidly associated with the consumable electrode holder and the other one has a recess filled with a current-conducting liquid medium receiving the rod end face directed towards the bar. The bellows space defined by the bellows proper, the casing and annular projection is filled with a liquid, variations in the pressure thereof being indicative of the mass of the consumable electrode.

Abstract: A long acceleration module is provided for use with a current sensor which provides an output voltage which varies with load current. There is also provided an inverse time overload logic module which controls the tripping of a circuit breaker to protect the lines in which the load current flows in relationship to the output voltage of the current sensor. The long acceleration module allows motor startup when a motor is connected to the lines to be protected. The long acceleration module purposely simulates a relatively low voltage for the input to the inverse time overload logic module during the motor startup time when high but generally non-dangerous currents are drawn by the accelerating motor.

Abstract: System for supplying current to a group of high-current resistance furnaces including a plurality of transformers switchingly connectible sequentially to the individual furnaces singly and together in parallel, the group of furnaces being subdivided into two subgroups of furnaces, each having one of said transformers associated therewith, and including a third transformer selectively switchingly connectible in parallel to the one and the other of the two subgroups of furnaces.

Abstract: An apparatus for feeding charge to an electric smelting furnace is disclosed. The apparatus comprises a single feed hopper and a single feed tube to a separation box from whence charge can be distributed in the furnace. Segregation of the charge being fed is substantially reduced by a system of automatically operated valves.

Abstract: A detector for an anti-lock vehicle brake system in which a d.c. signal proportional to wheel speed is produced and compared against a rate of change reference signal. An output control signal is produced when the rate of change of the wheel speed signal exceeds the rate of change of the reference signal.

Abstract: In the manufacture of semiconductor components thin films of submicron thickness are in widespread use. To produce the submicron thick films free of entrapped pockets of air, a platform, to which a substrate surface is mounted, is initially caused to oscillate in a shaking motion to produce a shearing force to lift minute pockets of air trapped at the liquid-substrate interface to permit migration to the surface of the liquid where they escape. This initial oscillating operation is provided by a permanent magnet A-C motor driven as a synchronous motor by the output of a frequency generator. The motor control circuit, including the frequency generator, energizes the A-C motor to initially cause the oscillating motion of the platform (chuck) carrying the substrate surface. After the initial time period of oscillating motion, the control circuit provides a high frequency signal to the motor for high speed rotation in one direction to produce a drying action to the thin, film-forming liquid.

Abstract: A furnace of the kind in which molten glass is heated by electrode means defining separate respective heating zones situated in horizontally spaced regions of the furnace chamber, glass being withdrawn along a withdrawal flow path extending between the heating zones to the outlet. Additional heating means is provided to heat the glass at a locality above the withdrawal flow path in the vicinity of the outlet, producing an upward convective pressure to counteract downward entrainment effects caused by flow of glass to the outlet.

Abstract: Overload protection of a three-phase submersible pump motor, such as the type used downhole in an oil well, is obtained with a solid state digital logic control system that monitors each of the three phase currents and shuts the pump motor down if any of those phase currents indicates an overload condition. A time delay is introduced before shutdown to avoid undesired nuisance shutdowns otherwise caused by transient or momentary conditions. The shutdown time delay is variable and is inversely proportional to the amount of overload in order that greater overloads result in faster shutdowns.

Abstract: An electroslag remelting furnace with relative displacement of a mould and an ingot being cast is provided with an electric control circuit for controlling the displacement of consumable electrodes, an electric control circuit for controlling the displacement of the mould, and an electric control circuit for controlling the power input in accordance with the rate of the ingot remelting, all of the electric circuits being electrically coupled to one another.

Abstract: A DC arc furnace of the type having an arcing electrode and a withdrawable starting electrode for initially forming electrical contact with a charge of metal pieces, and an electric connection for a subsequently formed melt in the furnace, has a DC power source positively connected directly with the starting electrode and the melt connection, and negatively connected with the arcing electrode. When initially charged with solid metal pieces, the starting electrode is contacted with the charge so that an arc is formed between the pieces and the arcing electrode until a melt is formed for contact with the connection for the melt. With both the starting electrode and melt connection directly connected positively with the power source, without intervening control equipment, the current automatically commutates from the starting electrode to the melt connection as the melt forms so as to contact the latter.

Abstract: An electrical switch device comprising a bi-stable double-throw switching relay having magnetic or mechanical means for contact holding, and at least one capacitive and/or inductive energy storing component to supply the switching relay with trailing edge trigger. The energy storing component is connected to a first contact of the relay, receives energy while the first contact is selected or reset and while the common contact of the relay is connected to a direct-current power source, and it discharges energy upon disconnecting the common contact from the power source so as to drive the relay, resulting in a second contact being selected. Such a switch device permits only the first pulse to reach the first relay contact after reset.

Abstract: An exhaust system for use with an electric arc melting furnace having a crucible and an upwardly directed mouth covered by a roof, and a device coupled to the roof for projecting it upwardly along an axis and pivotally about the axis to a position out of registry with the mouth for providing access for charging the furnace, and a device for tilting the furnace for tapping and slagging. In one embodiment the fumes exhaust system comprises an exhaust fan, a telescoping main fumes exhaust duct flexibly coupled at one end to the exhaust fan, a coupler flexibly connected to the other end of the main fumes exhaust duct and a tapping and melting manifold and hood flexibly and telescopically connected to the coupler. The tapping and melting manifold and hood are connected to the roof and project vertically along the roof axis and pivot about the roof axis with the roof to a position out of registry with the mouth. A slagging manifold and hood are mounted on the furnace and connected to the coupler.

Abstract: Electronic safety circuit intended to produce an output signal in the event of wearing out or failure of one of its components, the circuit comprising a magnetic circuit having a rectangular hysteresis cycle, a control circuit connected to the magnetic circuit and to the other components which are under surveillance, this control circuit acting in a balanced fashion on the magnetic circuit when all the components of the circuit under surveillance function normally, but producing an unbalanced action when at least one of these components is defective, and an output circuit producing an output signal in the event of an unbalanced action on the magnetic circuit.

Abstract: An electric arc furnace for DC operation has an electric connection for a melt in the furnace's hearth, in the form of an elongated metal connector having a refractory enclosure exposing an inner end of the connector for contact with and incidental melting by the melt, with means for cooling the connector between its inner and outer ends and removing heat at a rate preventing the connector from melting throughout its length to its outer end. The connector has a cross-sectional area large enough to carry the current required for forming a heating arc between an electrode and the surface of the melt, and the connector has similar composition as the melt as exemplified by a steel connector for a steel melt.

Abstract: The invention covers methods and apparatus for controlled flue gas combustion during operation of a closed electric arc reduction furnace to produce metals and metal alloys while feeding a burden to the furnace chamber. The furnace chamber is closed by means of a flue gas hood of reduced height, complete with electrode conduits, gas exhaust pipes and charge devices. The flue gas hood is provided with one or more controlled recycled combustion gas and air supplies, through which combustion air and recycled gas enters the furnace chamber at spaced points thereover for maintaining a reduced temperature level adjacent the hood ceiling surface. The quantities introduced depend upon the prevailing temperature and/or gas analysis of the flue gas in the furnace chamber.

Abstract: Arrangement for and methods of operating electrically heated submerged throats between glass melter and final conditioning zones are disclosed which enable the pull rate of glass to be reduced while maintaining temperature control and to be stopped without freezing the molten glass in the throat. High rates of heat loss in the throat region are compensated for with a high voltage power supply to electrodes positioned for Joule effect heating of the glass in the throat. Thermal adjustment at maximum pull rates is enhanced by the use of cooled electrodes in the throat as heat extractors with no electrical energy supplied. Low or zero pull rates can be tolerated without throat freeze-up by connecting additional voltage sources in series with the supply to the throat electrode.