摘要:
A pulse-inverter, especially a transistor inverter, is required to generate a system of polyphase output voltages as symmetrical as possible, having, for instance, trapezoidal waveforms. For this purpose, several reference voltages having different waveforms are generated wherein each section of an output voltage coincides with a section of a reference voltage. These reference voltages are pulse-width-modulated with a high-frequency sampling frequency and an inverted sampling frequency to form pulse width modulated reference voltages and pulse width modulated inverted reference voltages, respectively. The pulse-width-modulated reference voltages and pulse width modulated inverted reference voltages are coupled to the control lines of the inverter switches so as to generate, section by section, the output voltages having the reference waveform. All reference voltages and components used for generating the driving signal for one inverter output are also used for generating the driving signals of the other outputs so that a symmetrical system of driving voltages is produced without costly adjustments.
摘要:
An apparatus for delivery and removal of mandrel rods for use with rolling mills. A plurality of rocking levers are arranged one behind the other in the direction of rolling and are pivotable into upper and lower positions. Free ends of the levers are provided receivers for receiving the mandrel rod. The pivot or rocking levers are two-armed angle levers which are slidably mounted in two different positions such that in the first position the receivers on the angle levers are maintained in the vertical projection through the rolling axis and in the other position are offset from such vertical projection.
摘要:
The invention relates to acryloyl-containing polyesters having acid numbers AN of 1-50 mg of KOH/g of substance and having been polymerized from cocondensed units of(A) 1.0 mole of at least one dicarboxylic anhydride,(B) 0.02-0.08 mole of at least one saturated dihydric polyether alcohol having a molecular weight Mn of about 1,000 to 2,000,(C) 0.48-0.42 mole of at least one dihydric saturated alcohol,(D) 1.0 mole of at least one trihydric saturated oxyalkylated alcohol with a degree of oxyalkylation of 2-6, up to 50 mole-% of said oxalkylated alcohol may be replaced by a trihydric, saturated, non-oxalkylated alcohol, and(E) 1.0-2.0 moles of acrylic acid, to a process for their preparation, and to their use as radiation-curable binders in aqueous emulsion preferably for coating wood and woodlike materials, for which the presence of customary external surface-active agents and reactive radiation-curable diluents is not necessary.
摘要:
A multi-part piston ring, containing an at least single-part spring support which is provided with a piston ring joint region and an at least single-part spring element, which is positioned in a groove provided in the region of the inner circumferential face of the spring support, wherein the wall thickness of the spring support is essentially equal in the region of the ends of the spring support facing the piston ring joint and in the rear region of the spring support, and a pocket which extends over a circumferential range of at least 60° and is created by local reduction of the wall thickness of the spring support is provided in each case between the rear region and the piston ring joint ends.
摘要:
A filling neck to feed fuel into a motor vehicle tank using a filling nozzle, exhibiting the following features: a slotted drive ring comprising an insertion portion conically tapering toward the vehicle fuel tank, the cross-sectional constriction being less than the filling nozzle's cross-section; the drive ring, facing the fuel tank comprises, on at least one side of said gap, a locking segment; the drive ring is configured in floating manner in a cup-shaped housing portion of the filling neck, the outside diameter of said ring being less than the inside diameter of the cup-shaped housing portion; a sealing element is associated with the distal end of the drive ring, blocking access to the tank in its closed position; the drive ring's locking segment engages and keeps the sealing element in the locked position, and moves into the open position when said drive ring is expanded by the filling nozzle.
摘要:
The invention relates to a terminal strip (1) for telecommunications and data technology, comprising a housing and wire connection contacts (50, 60), first wire connection contacts (50) being accessible from the upper side (19) of the housing and second wire connection contacts (60) being accessible from the upper side (19) or from the lower side (29) of the housing, and electrical interfaces being accessible from the upper side (19) of the housing, which interfaces (70, 74) are connected to the first and/or second wire connection contacts (50, 60), the housing having a housing upper part (10), a housing lower part (20) and a housing central part (30, 30′), the housing central part (30, 30′) having receptacles, in which the first and second wire connection contacts (50, 60) and the electrical interfaces (70, 74) are partially guided and mechanically supported.
摘要:
A sliding element comprises at least one surface for sliding contact with a running face, wherein a wear layer and a run-in layer made from carbon are applied to the surface, and is characterized in that the run-in layer comprises hydrogen and nanocrystalline carbide phases. In a method for manufacturing a sliding element, the run-in layer is applied by means of a PVD process. A sliding system has an above-described sliding element and a body having a running face. A coating for a sliding element comprises a wear layer which can be applied to the upper side of the sliding element, and a run-in layer which is configured as a carbon layer, and is characterized in that the run-in layer comprises hydrogen and nanocrystalline carbide phases.
摘要:
The invention relates to a method for producing polymers, in particular synthetic nucleic acid double strands of optional sequence, comprising the steps: (a) provision of a support having a surface area which contains a plurality of individual reaction areas, (b) location-resolved synthesis of nucleic acid fragments having in each case different base sequences in several of the individual reaction areas, and (c) detachment of the nucleic acid fragments from individual reaction areas.
摘要:
The present invention relates to a weld-on fastener for an electrical contact with a weld nut (1) which, on its topside has an electric contact face (9) and, on its bottom side, has an annular axial projection (6) which surrounds a cavity (4) of a pre-determinable depth (T), and with a screw (3) screwed into the weld nut (1), which screw (3) also has an electric contact face (9), a spacer ring (2) being clamped between the contact faces (9). The spacer ring (2) preferably has a thickness (D) which is approximately equal to the depth (T) of the cavity (4). When the spacer ring (2) is clamped in, the screw (3) ends approximately flush with the end of the internal thread (12) of the weld nut (1). This combination is distinctive in that it has only a low overall height, no metal scabs reach the thread (12) during welding-on, the contact faces (9) are protected during assembly and the welded connection can absorb high torques even when welding onto thin work pieces (7).
摘要:
The invention relates to a method for the determination of analytes using carrier chips comprising arrays of different receptors in immobilized form on the surface of said chips. The method is performed dynamically in several cycles. Information obtained in a previous cycle on the modification or alteration of said receptors is used in the following cycle.