Leybold-heraeus Gmbh

Leybold-heraeus Gmbh & Co. Kg

Siemens Aktiengesellschaft

Leybold Aktiengesellschaft

Friedrich W Thomas

Wolfgang Sperzel

Wolfgang Timpe

Konrad Priess

Jurgen Petzoldt

Peter Burkle

The invention relates to a device for the detection with measuring techniques of the temperature course of a metal or metal alloy melt in a container (39) which is influenceable by a heating device (22 to 24) and a cooling device (33). The temperature course is herein detected via a thermal camera (49) which is directed toward the region of the solidification front (48) of the melt. The data supplied by the thermal camera (49) are used for the purpose of determining the thermal gradient along on a coordinate of the container (39) and to control the heating device (22 to 24) according to the thermal gradient. Moreover, the data supplied by the thermal camera (49) are used for the determination of the solidification velocity of the melt to regulate the cooling device (33) in accordance with this solidification velocity.

Device for the detection of the temperature course of a metal or metal

A method and apparatus for measuring the diameter of a monocrystal during crucible drawing determines the brightness profile at the melt/monocrystal change-over point. The spacial position of maxima in the brightness profile in relation to a reference point indicates the diameter. The brightness profile is obtained by optically scanning the melt/monocrystal change-over point with a mirror rotating about a horizontal axis, applying the optical beam reflected by the rotating mirror to a row of photosensitive elements in parallel with the axis, and analyzing the outputs corresponding to the brightness profile for determining the diameter.

Method and apparatus for measuring the monocrystal diameter and the melt

A method and an apparatus for converting a three phase input into a constant voltage to a load, which voltage is substantially free of harmonics and ripples includes dividing the voltage to the load into two component voltages, with one component voltage comprising at least 80% of the total. The one component voltage is maintained constant and load independent. The voltage to the load is compared to a first reference voltage to obtain the difference therebetween and the value of the other component voltage is adjusted to minimize the difference. The two component voltages are added to form the voltage to the load.

Method and voltage source for producing a smoothed voltage from

A system for the control of power of a high-voltage electron beam generator having a cathode and a control electrode for the cathode, has a controller at ground potential, a pulse generator for the production of square-wave voltage pulses symmetrical with ground potential, a transformer for transferring high-voltage potential to the beam generator including a primary winding substantially at ground potential and a secondary winding at high-voltage potential, a full-wave rectifier connected to the secondary winding and a filter connecting the rectifier to the cathode and to the control electrode. The filter comprises an LC combination of at least two LC members connected in series, in conjunction with at least two capacitors, one parallel to the cathode-control electrode and the other parallel to the full-wave rectifier, the resonance frequencies of the LC members being in a ratio of approximately 2:1.

System for controlling the power of a high-voltage electron beam

The invention relates to a method and a circuit for the regulation of the discharge process in a cathode sputtering apparatus equipped with current, voltage and pressure regulators for controlling the sputtering process. A temperature rise in the discharge area in the course of operation is unavoidable, and, if constant pressure were maintained, this would result in a reduction of the charge carrier density and hence in a reduction of the discharge current, resulting simultaneously in a change in the rate of deposition. The invention resides in regulating to a programmed or constant value, not the pressure but the discharge current, doing so by varying the pressure within certain limits. For this purpose, while the sputtering voltage is maintained constant, a current reference level is given with which the actual current of the discharge is compared. Any current deviations are used for the purpose of operating the pressure regulator such that the current is maintained constant in the discharge area. This can be accomplished in an especially simple manner by operating the metering valve for the feeding of the sputtering gas in a current-related manner.

Method and system for regulating the discharge process in a cathode

The invention relates to a system for regulating the depth of immersion of melting electrodes in electrical slag remelting furnaces, consisting of an apparatus for the detection of the reciprocal resistance correspondence to the conductance and for changing this conductance upon the spatial displacement of the end of the electrode within the slag layer, a signal corresponding to the conductance being relayed to a regulating system for the electrode drive.

Apparatus for regulating the depth of immersion of consumable electrodes

The invention relates to a system for regulating the depth of immersion of melting electrodes in electrical slag remelting furnaces, consisting of an apparatus for the detection of the resistance and for changing this resistance upon the spatial displacement of the end of the electrode within the slag layer, a signal corresponding to the resistance being relayed to a regulating system for the electrode drive.

Apparatus for regulating the immersion depth of electrodes in

The invention concerns a converter arrangement for electrode melting furnaces, particularly for electric slag remelting of metals. A current regulator in the form of a PI controller is associated with the converter arrangement. The former is influenced by an actual current value, a reference current value, and additionally, by a control quantity. The control quantity replaces the current regulation of the regulator by a voltage control in dependence on periodic or aperiodic conditions which may be due to operational causes or to trouble and interfere with the melting process in the furnace. More particularly, for the duration of such conditions, the control quantity causes the output voltage of the regulator, which voltage acts on the control unit feeding the converter, to be limited upward to an adjustable value.

Growing community of inventors

Gelnhausen, Germany

Friedrich W Thomas