Abstract: The invention relates to a dimming circuit arrangement for operating a high-pressure sodium lamp L with controllable color temperature. The lamp is supplied with current pulses having a controllable duty cycle D. A change in the color temperature can be achieved through a change .DELTA.D in the duty cycle D and a simultaneous change .DELTA.P in the power supplied to the lamp, while the relation .DELTA.D/.DELTA.P>0 is satisfied.

Abstract: A method of microfiltration, ultrafiltration and pervaporation, which also can be utilized for reverse osmosis of suspensions and emulsions, and for gas separation including providing a tubular membrane wound of wire and having a plurality of windings, the distance between windings establishing filter pores, passing a desired material between the windings to filter the material to a desired pore size and exerting a desired axial pressure on the membrane windings to adjust the distance between windings and the pore size to a predetermined amount.

Abstract: A circuit arrangement for starting and operating gas discharge lamps with current of higher frequency comprises an electronic ballast unit connected to a direct voltage input source (2). An electronic switching element (3), which is controlled by a control device (8), is connected in series with an inductive element (4), and the discharge lamp (5). The lamp current flows through the inductive element from which a voltage is derived which is supplied to the control device as a supply direct voltage supply via a rectifier (14) and a smoothing capacitor (16). A first connection terminal of the smoothing capacitor is connected through a first ohmic resistor (18) to a first terminal of the direct voltage input source and a second connection of the capacitor is connected through the lamp (5) to a second terminal of the direct voltage input source.

Abstract: An apparatus for introducing a fuel additive into the fuel tank of an automotive vehicle comprising a pumping device including a pneumatically actuated displacement pump the pumping element of which is displaceable by pressure against the force of a pretensioned spring by means of a control valve and the control valve is preferably directly actuable by the lid of the fuel tank.

Abstract: In a circuit arrangement for starting and operating a high-pressure gas discharge lamp (8) by means of a voltage converter comprising at least one semiconductor switch (5, 6), which can be switched periodically to the conductive and to the non-conductive state by a control unit (32, 33, 34) in such a manner that the lamp receives a pulsatory supply current having an operating duty cycle between 0.1 and 0.7, the control unit (32, 33, 34) switches the semiconductor switch (5, 6) upon starting of the lamp (8) in such a manner that the duty cycle upon starting (starting duty cycle) is increased with respect to the operating duty cycle.

Abstract: Disclosed are very pure zirconium and hafnium orthoesters and a method for their preparation. In this method the reaction between the halides of these metals and the alcohols is performed in the presence of hydrocarbons or chlorinated hydrocarbons, and the alcohol is not use in excess. The obtained orthoesters are in very pure form and not as addition products with alcohol. They can be isolated as solids.

Abstract: A circuit arrangement for operating at least one gas discharge lamp (5) with a periodically varying lamp current and adapted for connection to an alternating voltage source with a period N. The circuit is provided with a controlled semiconductor switch (3) and a control circuit for switching the controlled semiconductor switch with a switching period S in dependence upon a comparison between an actual signal proportional to the lamp current and a nominal signal derived from a voltage across the switching transistor (3).

Abstract: A pressure or draw bar of fiber-reinforced insulating material, in particular for a high voltage circuit breaker. The pressure or draw bars of fiber-reinforced insulating material are provided with connecting elements for the introduction of force for operating the circuit breaker. The connecting apertures of the draw bar which allow connection to the circuit breaker should be simple to adjust and secure, but should be fixable in a manner which permits ready detachment. The connecting apertures of the connecting elements are arranged in a fork part, to which a slit pipe part with external threads lies adjacent. In the slit pipe part a spreading body is arranged held by a screw, which in the region of the fork part has a surface accessible for generating a rotational motion. The spreading body can thus by spreading apart the slit pipe part determine the height of the connecting apertures with respect to the bar. The fitting body is surrounded on the outside by a ring as screening.

Abstract: A sole plate (1) for an ironing device, comprising a base body (12) of high thermal conductivity which is preferably an alumimum casting and has on its ironing side (27) a porous coating of a mechanically resistant compound (20), preferably metallic or ceramic materials. The mechanically resistant layer (20) of metallic or ceramic materials is coated with an organic bonding agent (26) having partcularly good sliding, antiadhesive and sealing properties.

Abstract: A novel method of blow molding and fluorinating plastic containers carried out in essentially three steps, including blow molding of the container at a first predetermined pressure in a mechanically locked mold with an inert gas, testing the mold for pressure tightness at a second higher level of pressure with an inert gas, and thereafter introducing a fluorine containing gas into the mold at a third level of pressure.

Abstract: Disclosed is a new method for the preparation of metallic acid esters of titanium, zirconium or hafnium wherein a halide of the metal reacts with an organosilane ester, resulting in the formation of partial esters of the metallic acids. The degree of esterification of the metallic acid ester can be controlled based on the organosilane ester and it is possible to obtain complete esterification of the metal halides. The metallic acid partial esters prepared by the method are very pure, and can be separated selectively from the mixture in a simple manner. The metallic acid alkyl esters obtained can very easily be further esterified to the metallic acid tetraalkyl esters with the formation of very pure tetraalkyl esters.

Abstract: The present invention relates to the esterification of the halides of titanium, zirconium or hafnium. The esterification takes place in two steps. The first step is performed in the absence of acid acceptors, and the alcohol is introduced into the metal halide dissolved in a solvent, without any appreciable contact with the gas phase. The reactor must be held at the boiling temperature. In this step at least half of the alcohol needed for the entire reaction is used. The second esterification step is performed in a known manner with the addition of acid acceptors after the hydrogen halide that formed in the first esterification step has been removed.

Abstract: A cam carriage for flat-bed knitting machines has at least one leading and trailing draw-down element, having a drive top plate and a bottom plate with a draw-down track located at opposite sides of a cam plate in which a draw-down element is placed movably between an alignment position and several casting-off positions in a guide slot, and the driven top plate is rigidly connected with a drive element at least in the direction of the draw-down position.

Abstract: The disclosure relates to a device with a flat component made of fiber-reinforced synthetic material and an end power induction unit, in particular a leaf spring or transverse link for motor vehicles. The flat component essentially enters the power induction unit without a change in fiber direction and is contained therein by a clamp. The contact point on the power induction unit is displaced by a distance "a", asymmetrically to the fiber levels such that a resultant of perpendicular forces and forces acting parallel to the fiber direction cause a reduction in stress and momentary relief. The portion of the flat component in the power induction unit has a length, using the perpendicular projection of the point of application of force, that is at least two-thirds of the length from the point of application of force to the resultant in the fiber plane or at least corresponds to quantity "a".

Abstract: A process and apparatus for the metered introduction of fine-grain materials, particularly pulverulent solid substances (i.e., coal dust) from a pressurized metering container which contains a supply of solid material, into an industrial furnace having a plurality of feed locations such as a blast furnace or cupola furnace is presented. The solid material is fed to the individual feed locations in a carrier gas stream through a conveying duct, the gas stream being highly charged with the solid material. The carrier gas is fed to the lower end section of the metering container in a flow which causes a local loosening in the lower section of the supply of solid material with the conveying ducts opening into the loosening region. The apparatus includes a metering container, which is designed as a pressure vessel and which is adapted to be filled at its upper end section with solid material to be fed to the furnace. The metering container includes at its lower end section a plurality of upwardly open chambers.

Abstract: A process and apparatus for producing steel from scrap. A cupola furnace is provided with a layer of coke in the vicinity of the tuyeres of the furnace, with scrap to be melted being supplied upstream of the layer of coke and molten scrap passing through the layer of coke to a converter located downstream of the furnace. The molten scrap is refined in the converter with oxygen, thereby producing a CO-rich converted waste gas, which is supplied to the coke layer and burned in the vicinity of the tuyeres.

Abstract: A circuit arrangement for A.C. operation of gas discharge lamps comprises a full-wave rectifier (1) connected to an alternating voltage source. The direct voltage is supplied to a combinatorial circuit part (3 to 8) in the form of a direct voltage converter, to which is connected a bridge circuit (9) which comprises four thyristors. The transverse branch of the bridge circuit includes the lamp (5). The full-wave rectifier (1) is followed by a smoothing capacitor (2) and an electronic switching element (14) is connected parallel to the bridge circuit (9). The switching element is switched to the conducting state in the vicinity of the zero passages of the input alternating voltage. As a result shortcircuits in the bridge circuit are avoided.

Abstract: A gear pump in which one rotating, toothed pump gear is supported axially displaceable in the pump casing and engaging an axially displaceable sliding part at least on the one face wall of the pump gear. The sliding part is adapted to overlap the operating space or zone of engagement of the displaceable pump gear against the other, axially stationary pump gear, with hydraulic relief provided by the pump casing and/or the sliding part by pocket-like recesses on the side diametrically opposing the pressure side of the pump across the displaceable pump gear, the recesses hydraulically communicating with the pressure side of the pump.

Abstract: A system serves to establish the spatial position of an object automatically. The system uses a computer-controlled lasar beam scanning technique to locate the three-dimensional positions of mirror devices in successive measuring stations spaced from the object.

Abstract: A circuit arrangement for igniting and operating gas discharge lamps comprises a choke coil (1) connected between a lamp (2) and an a.c. supply source. The choke coil has an inductance L and an ignition device (3) is connected to the lamp. A capacitor (9) having a capacitance C is connected in parallel with at least a part of the choke coil in order to pass an ignition current to the lamp that is higher than the normal lamp operating current. The relationship betweeen the capacitive reactance of the capacitor and the inductive reactance of the choke coil is 1/.omega.C>3.omega.L.