Abstract: The invention relates to a device for recognizing the impact site (29, 37) of a charge carrier beam on a target. This device has two position-sensitive detectors (22, 23) above the target which have a given distance from each other and from the target and on which via imaging systems (24, 25) the impact site (29, 37) of the charge carrier beam is imaged by means of X-rays. The output signals of these detectors (22, 23) are placed on a special evaluation device which determines all three spatial coordinates of the impact site (29, 37) of the charge carrier beam.

Abstract: The invention relates to a device (20) for a unipolarly operated component (9) capable of storing energy. This device (20) can be applied, for example, in an asymmetrical half bridge circuit (1). It compensates the dc magnetic flux which originates due to the unipolar operation and, hence permits making relatively small in size the component (9) capable of storing energy. Using a current converter (25, 32) with suitable winding ratio as an automatic and load-dependent compensation device, moreover, permits very flexible adaptation to load changes. Such adaptation is, in particular, required when very high pulsating current occurs on the primary side with simultaneous secondary no-load operation.

Abstract: In a directly heatable crucible 3 for induction melting furnaces, especially for melting refractory and highly-pure metals, including an inductor coil 11 surrounding a crucible 3 and a housing 5, which at least partially encloses the inductor coil 11 and the crucible 3 and which forms together with the external wall 9, 9' of the crucible a closed chamber having an annular portion 10 and a flat cylindrical base portion 10'. This chamber is passed through by a cooling agent and the crucible 3 is made of the material to be molten.

Abstract: The invention concerns a measurement sensor for the detection of temperatures in metal or alloy melts. This measurement sensor consists of a thermocouple (41) surrounded by a ceramic capillary (24) which is closed at its end by means of an adhesive (45) or the like. This measurement sensor is directly, i.e. without further sheathing, introduced into the melt (FIG. 3a).

Abstract: A device and a method for the control and monitoring of a deflectable electron beam is provided for the working of metal wherein the electron beam is not permitted to go beyond an allowed working area. With this device with the aid of a Teach-In method the limits are entered into a computer. The computer generates an image of the areas allowed for the electron beam in a particular area of a special memory. This memory is so organized that the addresses of the point of the particular areas correspond to the digitized coordinates of the point of impingement of the electron beam. The characterization of the allowed and forbidden target points of the electron beam takes place through placing or deleting respectively the assigned bits in the special memories.

Abstract: A reaction gas is admitted in the immediate vicinity of a target on the cathode and a plasma is generated between the target and a substrate to be coated. The intensity of the spectral line of a target material is measured, and is used to provide a first signal with a relatively short time constant to a controller via a first control circuit. A property of the finished coating is sensed after the substrate leaves the coating zone, and is used to provide a second signal with a relatively long time constant to the controller via a second control circuit. The controller uses the combined signals to regulate the admission of the reaction gas so that a pre-established property of the finished coating is kept substantially constant.

Abstract: The invention concerns apparatus for detecting the position of incidence (2) of a beam (1) of charge carriers on a target (3) wherein X-rays (4) starting from the position of incidence (2) are detected by detector (7) connected to an analyzing circuit (9) An imaging system (5, 50; 10, 11, 12) is provided which can cover all the positions (P.sub.1 . . . P.sub.8) that the positions of incidence (2) can take up and projects them on the sensing surface of a position-sensitive detector (7), wherein the projected coordinates (x', y') are directly proportional to the coordinates (x, y) of the position of incidence (2). In addition, a filter (6) highly transparent to the X-ray radiation range emitted from the position of incidence (2) is arranged between the target surface (3) and the position-sensitive sensor (7). The position-sensitive detector (7) emits electric signals which depend from the coordinates (x, y) of the position of incidence (FIG. 1).

Abstract: In automatic melting crucible tipping it is important that, starting from a certain angular position, the melting crucible (1) is tipped according to a predetermined model until emptying is complete. This model can be obtained, for example, by the so-called teach-in process and can be stored in an analog or digital memory (89). In order to prevent abrupt movement of the crucible (1) when the molten material touches the pouring lip (3) of the crucible (1) when the pour-lip angle has been reached, according to the invention a correction arrangement (108, 109, 37) is provided which enables the tipping process to proceed continuously and without abrupt movements even in the case of different pour-lip angles.

Abstract: Apparatus for controlling the distance of a melting electrode from the surface of melted material in a vacuum arc furnace which uses short circuits caused by the droplets between the melting electrode and the surface of the melted material as a control criterion. The short circuits occurring within a given period of time--the so-called droplet rate--are determined and supplied to an averager which is connected with a controller that controls an electric driving mechanism for the melting electrode. According to the invention, the controller is responsive to a signal representing the difference between the reciprocal value of the droplet rate signal formed by the averager and a desired time, this desired time being equal to the desired average time between two consecutive droplet short circuits.

Abstract: A power supply apparatus, in which the three phases of an alternating-current main are connected each through rectifier elements connected in antiparallel to the primary winding of a three-phase transformer. The secondary windings of this transformer are connected through rectifiers to a load device, such as an electron beam gun or other such device which produces short-circuits while in operation. Measuring sensors are provided on the primary AC side which, in the presence of an excess current on the primary AC side, block controlled rectifier elements. The blocking takes place very rapidly because GTO thyristors are used as rectifier elements. The decay of the magnetic energy in the transformer is achieved by the fact that the primary side of this transformer is connected in delta.

Abstract: The invention relates to an inverter with a direct-voltage source and a chopper section, the chopper section having push-pull switching at a frequency f.sub.0. A parallel tuned circuit, the resonant frequency of which is 2f.sub.0 is provided between the direct-voltage source and the chopper section.

Abstract: The invention concerns a converter (2) provided with GTO thyristors the frequency and characteristic shape of its output voltage (U.sub.A) being constrained by a load (3). The frequency of the converter (2) is matched to the constrained output voltage (U.sub.A) with the aid of a regulating circuit (4). Non-simultaneously switched GTO thyristors are switched on and off in a predetermined timed relation to each other (FIG. 3).

Abstract: 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.

Abstract: 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.