Abstract: The invention relates to an electrode material for potentiometric or amperometric electrochemical sensors with the chemical composition Ln.sub.1-2 A.sub.1-x B.sub.x O.sub.3, where Ln is at least a lanthanide cation or a mixture of rare earth cations, A is at least a trivalent transitional material, and B is at least a trivalent or bivalent redox-stable cation.

Abstract: Porous, ceramic layers, which also have a diffusion-limiting action, are as a rule manufactured by selectively adding pore formers to the ceramic sinter material. The porosity of the layer created in this way lies in the micrometer range. The known processes for manufacturing layers of this type are intended for application to planar substrates. Suitability for spherical surfaces and a porosity of the layer in the nanometer range is provided herein by an oxide ceramic powder having a BET specific surface area in the range of about 5 to 50 m.sup.2 /g and having a mean primary particle size of about 20 to 450 nm. The powder is first pretreated at a temperature of about 800.degree. C. to 1150.degree. C. and then mixed with untreated, oxide ceramic powder. The mixture is then applied to a high temperature-stable base, and burned-in (fired) at a temperatures of about 1000.degree. C. to 1350.degree. C. Optionally, instead of the thermally pretreated oxide ceramic powder, a recrystallized glass powder can be used.

Abstract: According to the state of the art, either two separate sensor elements are generally used to determine the exhaust gas temperature and the air/fuel ratio, lambda, or the temperature and lambda readings are not taken simultaneously, at least at temperatures of less than 250.degree. C. In addition, sufficiently precise simultaneous measurement is only possible during stationary operation. The process according to the invention and the corresponding sensor arrangement now make it possible to obtain a precise temperature and lambda reading at a minimal degree of metrological complexity, especially under non-stationary conditions, in that a heated sensor, which exhibits a temperature-sensitive and oxygen-sensitive element on a carrier element, is used to measure the exhaust gas temperature, even at low temperatures with the heating system switched off, while a lambda reading is obtained simultaneously, with the latter being possible only at higher temperature ranges.

Abstract: A process is provided for producing a sensor arrangement for measuring temperature with a temperature-sensitive measuring resistance element which has a thin, metallic resistance layer electrically-insulated toward the outside on a ceramic substrate and free-lying contact surfaces, which are connected electrically-conducting and directly mechanically fast with high-temperature-resistant conductor strips, electrically insulated from one another, on a ceramic board. The measuring resistance element is bonded and fastened on one end of the board by laying it on a still moist thick-film conducting paste printed on immediately before outfitting on the board and subsequently burning it in. On the end of the board away from the measuring resistance element, contact surfaces for connection of a plug or cable are arranged. The temperature sensor, a standard component in the form of a flat measuring resistance element, is applied wirelessly as an SMD component on the ceramic board.

Abstract: A sensor arrangement for a film type anemometer which includes a carrier plate; a precision resistor; a planar, elongated heating resistor supplied with an adjustable power supply; and a retaining device. The operational temperature of the heating resistor is increased by a fixed predetermined differential amount versus the temperature determined by the precision resistor. The heating resistor has at least one resistive layer disposed on a substrate. The heating resistor is attached in a bridge-like fashion in a recess of the carrier plate. The retaining device has a low heat transfer and has two opposite attachment areas which retain respective ends of the heating resistor. Each of the attachment areas being directed towards respective ends of the heating resistor and each attachment area having at least a bearing surface, a lateral peripheral surface and a longitudinal peripheral surface which extends in the longitudinal direction of the heating resistor for receiving an end area of the heating resistor.

Abstract: A system for monitoring the operatibility of catalytic converters and/or lambda probes in exhaust gas detoxification systems. It is characterised in that a pollutant sensor is placed downstream of (in relation to the exhaust gas stream) or in the catalytic converter, in that the lambda value and/or oxygen content of the exhaust gas are altered by a specific amount either by the engine or by a device, and in that the electrical output signal from the pollutant sensor is compared in a comparator circuit to a value curve stored in a storage unit and corresponding to the defined alteration of the lambda value.

Abstract: A a process as well as an immersion sensor for measuring an electrochemical activity of a layer lying on a melt is provided, using an electrochemical sensor, which has a measuring cell and a counter electrode. In order to make possible reliably reproducible and accurate measurements in the layer, the measuring cell and counter electrode are first immersed in the melt, wherein the measuring cell and counter electrode are protected from contact with the layer and wherein the measuring cell and counter electrode are brought into contact with the melt and are heated. After that, the measuring cell is pulled up to perform the measurement in the layer, wherein the counter electrode is located in the melt during the measurement. For this purpose, the measuring cell and the counter electrode have a protective cover, and the measuring cell is arranged, in the immersion position of the sensor, above the counter electrode.

Abstract: A sampling device for molten metals, especially for molten cast iron or pig iron, has a sampling chamber arranged in a refractory body mounted on a carrier. The sampling chamber is bounded on two opposing walls by one metal plate each, and has at least one inlet opening for molten metal on a further wall. In order to create a sampling device with which samples are obtained which have the best possible white solidification and at the same time have the sturdiness necessary for an automatic sample analysis, a metal disk is separably arranged in the interior of the sampling chamber on at least one of the two metal plates. The diameter of metal disk is smaller than the diameter of the sampling chamber, and the thickness of the disk is less than the thickness of the sampling chamber.

Abstract: Oxygen sensor for measuring resistance as a function of oxygen partial pressure, made of alkaline-earth-doped perovskitic lanthanum ferrites with the general formulaLa.sub.1-x Me.sub.x FeO.sub.3-.delta.where Me is one of alkaline earth metals, Mg, Ca, Sr, and Ba, x is a degree of doping of the lanthanum ferrites. The oxygen sensor oxygen deficit of anion is 6=0 to 0.25, and the degree of doping of the lanthanum ferrites is x=0.1 to 0.3 and is selected to provide a temperature independent resistance property to the oxygen sensor in a lean range.

Abstract: The invention relates to a catalytic layer system on a resistive gas sensor, especially on a resistive gas sensor layer on a titanate base, with at least one first layer and a second layer lying over the first layer, where, according to the invention, the first layer exhibits a catalytically active substance whose volume percentage in the layer ranges from 20 to 80%. In addition, the first layer contains a titanate that corresponds to at least one titanate of the underlying gas sensor layer. This attribute guarantees favorable adhesion between the layers. Furthermore, an oxide mixture that contributes to the improved mechanical stability of the layer system is provided in the second layer instead of the catalytically active substance. To manufacture the catalytic layer system, the individual layers are applied to the sensor in a screen printing process, which allows for a rational method of production and the precise dosing and distribution of the individual layer components.

Abstract: An electrode material is provided for electrochemical sensors, particularly for sensors detecting combustible gases. For these types of applications, perovskite electrode materials are known which, however, by modification of their oxygen stoichiometry, have a considerable charge carrier mobility. These defects are the causes for an additional, catalytic activity with oxidation processes at electrodes. The measurement of hydrocarbons from combustible gases is thus distorted with electrode materials of this type. These disadvantages are overcome by making such electrode materials from mixed oxides with non-perovskite crystalline structures, which have chemical compositions of one or more of the following general formulas: (A/D).sub.3-y B.sub.x C.sub.5-x O.sub.12.+-..delta., D.sub.1-y B.sub.1-x C.sub.x O.sub.4.+-..delta., D.sub.2-y B.sub.8-x C.sub.x O.sub.16.+-..delta., D.sub.2-y B.sub.1+x C.sub.1-x O.sub.5.+-..delta., or D.sub.2-y B.sub.x C.sub.2-x O.sub.7.+-..delta.

Abstract: In a temperature sensor with a platinum resistance thermometer accommodated in a tube-shaped housing, the platinum resistance layer belonging thereto should be protected against pollution or contamination of the platinum, since the electrochemical characteristics of platinum can be reduced by substances in the surroundings in the event of too low a partial pressure of oxygen. For this purpose, a mechanically solid and liquid-impermeable, connection is provided in the connection region of the tube-shaped housing, which permits an admission of air-oxygen into the housing from the environment of the connecting cable. The air-oxygen admission is made possible through a liquid-impermeable oxygen-permeable jacket for the connecting cable and/or over an accompanying connecting plug, whereby the admission of air-oxygen takes place along a glass filament filler running parallel to the electrical leads inside the jacket of the connecting cable.

Abstract: The invention relates to a process for monitoring the operativeness of a catalytic converter used to clean the exhaust gas in an internal combustion engine that is regulated by a lambda sensor through temperature measurement with a heat tone sensor exhibiting a catalytically active coating. The process provides information on both the percentage of individual, non-converted exhaust components and on the current thermal load on the catalytic converter. Readings are taken by the heat tone sensor at time intervals corresponding to the normal regulating frequency of the lambda sensor. This results in a quadratic function in which the height of the amplitude represents the percentage of non-converted individual exhaust components. The mean temperature of the catalytic converter can be inferred by rectifying the quadratic function.

Abstract: A catalytic converter for cleaning exhaust from combustion processes, especially exhaust from internal combustion engines, and the manufacturing method thereof, the converter including a housing and a plurality of packets provided therein. Each of the packets includes at least one corrugated foil joined at contact areas to at least one flat foil, preferably by soldering or welding. The flat and/or corrugated foil is provided at least partially with a catalytically active coating. The spaces between the corrugated foil and/or between the at least one flat foil and the at least one corrugated foil define channels running parallel to one another through which the combustion gas flows. At least one electrically heatable foil is connected on or in at least one packet with good heat conduction.

Abstract: The invention relates to catalytic converters to be placed in the flowing exhaust of exhaust gas installations, preferably internal combustion engines, with a carrier material provided with a catalyst-containing ceramic coating and at least one temperature sensor applied in thick film technique, which is characterized in that the temperature sensor is located on the surface of the carrier material and that the catalyst-containing ceramic coating covers the temperature sensor.

Abstract: A universal connector apparatus for probes used for measuring one or more parameters of molten material which identifies a probe type is provided. The probes each include a probe connector having a plurality of contacts arranged in a contact configuration. The universal connector is adapted to be connected to a drop mechanism, and includes a receptacle which is complementary to and adapted to receive a probe connector. A plurality of contacts are located in the receptacle and are positioned to provide electrical connections with the probe connector contacts. An identifying device is electrically connected to the contacts in the receptacle to detect short circuits between the contacts.

Abstract: The invention relates to a gas sensor, preferably a lambda probe for determining pollutant and/or oxygen content in the exhaust of internal combustion engines or furnaces, with a metal housing that has mounting means for installing the gas sensor in an exhaust chamber, a ceramic part located inside the metal housing to receive a sensor support with sensor elements, one end of which projects into the exhaust chamber and whose other end is connectable with electrical terminals, characterized in that the ceramic part, in its area away from the exhaust, is secured by a positive connection in at least the radial direction in a metal housing and a sealing element is provided in an area of the ceramic part located downstream from the positive connection, said element being connected firstly with the outside wall of the ceramic part and secondly abutting a wall of the metal housing in a gas-tight manner.

Abstract: An electrically heatable starter catalytic converter (5) has a metallic housing (6) in which is arranged the actual catalyst (7) exposed to the exhaust gas flow, an electric resistance heating (8) and an electric connection line (10) that enters the housing (6) through an opening (9). The invention is characterized in that the electric connection line (10) is a metal-clad cable with at least one inner lead (11) electrically insulated from the metal cladding by a mineral (13). The inner lead (11) frictionally engages the electric resistance heating (8), and the metal cladding (12) enters the metallic housing (6) through the opening (9) and is welded or soldered to the edge of the opening (9) in a gas-tight manner.

Abstract: A device for conducting electrochemical measurements in glass or salt melts has at least one indicator electrode and one reference electrode arrangement. In order to be able to conduct very exact measurements, the tip of the indicator electrode intended to be immersed in the melt is constructed of a noble metal or noble metal alloy with at least one another noble metal, preferably iridium or an iridium alloy with other noble metals, and is mounted gas-tight in a heat-resistant tube. The indicator electrode is passed through the heat-resistant tube.

Abstract: In an internal combustion engine, a catalyst monitor includes a resistive type oxygen sensor positioned between the engine and the catalyst and a temperature sensor positioned proximate to the catalyst. The oxygen sensor measures an oxygen concentration of the engine emissions and the temperature sensor monitors a temperature of the catalyst and detects a light off time of the catalyst. The magnitude of resistance of the oxygen sensor is measured and compared to a predetermined threshold level. The catalyst light off time is compared to a predetermined time value. In addition, a lifetime temperature profile of the catalyst is generated and compared to a predetermined threshold temperature level. The results of the comparisons are used to establish whether the catalyst is operating efficiently.