Abstract: Of a gas detector 100, a chamber 105 formed between a center cover 150 and a cover 160 is a part of an air flow channel AF. A first shielding plate 165 is provided in the chamber 105. Water droplets that have entered the chamber from a chamber entrance 103 with air hit and adhere to an entrance-opposed surface 165E of the first shielding plate 165. The water thus adhering to the surface is pushed by the air flowing along the entrance-opposed surface 165E and by gravity, to thereby advance downward. The water then drips downward and is accumulated on a bottom wall surface 105WD which serves as an upper surface of a bottom wall section 161WD. The water is pushed by the flow of air, to thereby advance toward a chamber exit 104. The water is then drained downward from the chamber exit 104.

Abstract: A lightweight and portable analyzer is provided. At least one component of the analyzer is made from a lightweight material, such as ABS. A manifold can have a plate and gas passages ultrasonically welded together. By having at least one component made from a lightweight material, the analyzer is lighter.

Abstract: A hydrocarbon sensor and collector. An element that is capable of absorbing and releasing hydrocarbons is positioned in the air intake system of a vehicle, upstream from the engine and wholly in the airflow. The element has a plurality of chambers defined in it that allow air to pass through the element. The hydrocarbon sensor and collector also includes a means for detecting the level of hydrocarbons absorbed by the element.

Abstract: A heat generation amount qr/r per unit flow amount of combustible substances supplied to a catalyst is estimated based on upstream and downstream temperature information and supplemental engine information. A deteriorated condition of the catalyst is detected based on a judgement whether or not the estimated heat generation amount is smaller than a predetermined judging value D.

Abstract: A poison resistant combustible gas sensing element, a method for its production and a method for determining poisoning of the element. The element includes an electric heating element, an inner layer coated on the electric heating element and containing a precious metal catalyst supported on a porous oxide, the precious metal catalyst catalyzing combustion of a combustible gas to be detected by the element, and an outer layer overlaying the first layer, and containing a catalytic compound capable of trapping gases which poison the precious metal catalyst, the catalytic compound being supported on a porous oxide.

Abstract: A poison resistant combustible gas sensing element, a method for its production and a method for determining poisoning of the element. The element includes an electric heating element, an inner layer coated on the electric heating element and containing a precious metal catalyst supported on a porous oxide, the precious metal catalyst catalyzing combustion of a combustible gas to be detected by the element, and an outer layer overlaying the first layer, and containing a catalytic compound capable of trapping gases which poison the precious metal catalyst, the catalytic compound being supported on a porous oxide.

Abstract: Disclosed herein is a method and apparatus for analyzing, sensing and measuring the concentrations of various gases, including NOx, hydrocarbons, carbon monoxide and oxygen, in a multi-component gas system using chemical sensors and chemical sensor arrays. The sensors and sensor arrays use chemo/electro-active materials to analyze and detect the presence of gases.

Abstract: A method and apparatus for sensing a flammable vapor are described herein. Initially, a first thermal conductivity of a vapor at a first temperature and a second thermal conductivity of the vapor at a second temperature can be determined. Thereafter, a ratio of the first thermal conductivity signal to that of the second thermal conductivity can be calculated to obtain a primary “vapor” signal. The “vapor” ratio can then be compared to an “air” ratio of air without the vapor at the first temperature and the second temperature to obtain a secondary signal thereof. Such a secondary signal can then be compared to an alarm set-point value to thereby determine whether the vapor comprises a flammable vapor and a risk-reducing action thereof be taken.

Abstract: Intended for application on ducts through which flow a fluid at a high temperature, and particularly at a high pressure, comprising two bodies (4) and (8) which axially screw onto each other, one body (4) provided with a threaded neck (5) for attachment to the orifice of duct wall (3), which body (4) houses within it sensor element (2) of the probe which is thus placed inside the duct, with second body (8) screwed onto first body (4) and exerting on sensor element (2) the pressure required to secure it in its housing, with second body (8) further provided with an axial orifice through which passes a metallic tube (9) open to the exterior and which is provided with a metallic washer (10), soldered to said tube (9), which is separated from second body (8) by an electrically insulating washer (12).

Abstract: A combustible gas sensor includes an active element in electrical connection with a measurement circuit. The measurement circuit includes a thermistor network to compensate for the effect of changes in ambient temperature to the resistance of the active element. Another combustible gas sensor includes an active element having a geometric surface area no greater than approximately 0.5 mm2 in electrical connection with a measurement circuit. The measurement circuit includes a compensator that compensates for the effect of changes in ambient temperature to the resistance of the active element without compensating for heat lost by thermal conduction from the active element.

Abstract: The measuring sensor, particularly a lambda probe, has a ceramic sensor member retained at a high temperature during measuring operation. It is shielded from water droplets, carried along in the gas to be analyzed, by a heated protective housing, permeable for the gas to be analyzed, by which water droplets carried along in the direction of the sensor member are evaporated before reaching the sensor member. In this way, the water droplets are unable to cause any shock-like temperature drops at spots on the surface of the sensor member or material flaking.

Abstract: Disclosed herein is a method and apparatus for analyzing, sensing and measuring information related to the concentrations of various gases, including NOx, hydrocarbons, carbon monoxide and oxygen, in a multi-component gas system using chemical sensors and chemical sensor arrays. The sensors and sensor arrays use chemo/electro-active materials to analyze and detect the presence of gases.

Abstract: An improved, affordable, and rapid fluid mixture composition or process monitor based on a thermal microstructure sensor. This is preferably accomplished with a microbridge sensor design that has reduced susceptibility to interfering components of the mixture. The sensor described herein is therefore suitable for monitoring the concentration of at least one component in a fluid mixture when the fluid mixture consists of either (1) two components with very different thermal conductivities; or (2) three or more components wherein at least one component has a very different thermal conductivity and the effects of the other components can be largely eliminated, especially if the component of interest is hydrogen and the interference is from the variability in the concentrations of CO2 and H2O.

Abstract: A single pass analyzer includes multiple infrared sensors, a catalytic converter, a scrubber and a thermal conductivity cell all coupled in series to provide a single pass (i.e., one sample) analyzer which allows for fast analysis, allows for the speciation of hydrogen samples, requires no purging between different sample types, utilizes a single carrier gas, and eliminates molecular sieves and Shutze converters. The resultant analyzer provides improved quicker results with less plumbing (i.e., gas conduits and valving) in a single instrument.

Abstract: A hydrocarbon detector (20) includes a gas stream delivery element (26) configured to discharge a carrier gas (70) onto a surface (24). The carrier gas (70) serves to volatilize a hydrocarbon presence (22) from the surface (24). A gas stream recovery element (28) is configured to aspirate a sample gas (78) formed from the carrier gas (70) combined with the hydrocarbon presence (22) volatilized from the surface (24). A hydrocarbon sensor (58) detects the hydrocarbon presence (22) in the sample gas (78) and generates an output signal indicative of the hydrocarbon presence (22). An indicator (80) receives the output signal and indicates the hydrocarbon presence (22) in the sample gas (78). A heat source (72) coupled to the gas stream delivery element (26) heats the carrier gas (70) to further aid in the volatilization of the hydrocarbon presence (22).

Abstract: An exhaust gas sensor includes a housing and a sensor element supported by the housing. The sensor element includes a support member having an exhaust side, a reference side, and an aperture extending through the support member between the exhaust side and the reference side. The sensor element further includes an exhaust-side electrode on the exhaust side of the support member. The exhaust-side electrode is electrically connected to a contact on the reference side of the support member via a lead extending through the aperture. The aperture is sealed around the lead such that gas cannot pass through the aperture. The support member is oriented substantially parallel to the flow of exhaust gases when the exhaust gas sensor is installed on a vehicle. The sensor further includes a contact pin in the housing that engages the contact and biases the sensor element against a portion of the housing.

Abstract: An apparatus and a method for detecting a flammable gas in a gas mixture is provided. The apparatus includes a chamber that is equipped with an igniting device and a temperature sensor such that a flammable gas fed into the chamber may be ignited and that a temperature rise in the chamber cavity may be detected. A signal responding to the temperature rise is sent to a process controller such that a valve means for feeding the gas mixture into the system can be switched over to an ambient air supply for purging out the system and for avoiding the danger of explosion or fire. The apparatus and method are particularly suitable for detecting a flammable gas in an exhaust gas mixture of a semiconductor fabrication machine, however, they may also be used in detecting flammable gases in any other processing equipment which generates an effluent gas flow.

Abstract: A gas sensor for detection of oxidizing and reducing gases, including O2, CO2, CO, and H2, monitors the partial pressure of a gas to be detected by measuring the temperature rise of an oxide-thin-film-coated metallic line in response to an applied electrical current. For a fixed input power, the temperature rise of the metallic line is inversely proportional to the thermal conductivity of the oxide coating. The oxide coating contains multi-valent cation species that change their valence, and hence the oxygen stoichiometry of the coating, in response to changes in the partial pressure of the detected gas. Since the thermal conductivity of the coating is dependent on its oxygen stoichiometry, the temperature rise of the metallic line depends on the partial pressure of the detected gas. Nanocrystalline (<100 nm grain size) oxide coatings yield faster sensor response times than conventional larger-grained coatings due to faster oxygen diffusion along grain boundaries rather than through grain interiors.

Abstract: A method and apparatus for sensing a flammable vapor are described herein. Initially, a first thermal conductivity of a vapor at a first temperature and a second thermal conductivity of the vapor at a second temperature can be determined. Thereafter, a ratio of the first thermal conductivity signal to that of the second thermal conductivity can be calculated to obtain a primary “vapor” signal. The “vapor” ratio can then be compared to an “air” ratio of air without the vapor at the first temperature and the second temperature to obtain a secondary signal thereof. Such a secondary signal can then be compared to an alarm set-point value to thereby determine whether the vapor comprises a flammable vapor and a risk-reducing action thereof be taken.

Abstract: A combustible gas sensor includes an active element in electrical connection with a measurement circuit. The measurement circuit includes a thermistor network to compensate for the effect of changes in ambient temperature to the resistance of the active element. Another combustible gas sensor includes an active element having a geometric surface area no greater than approximately 0.5 mm2 in electrical connection with a measurement circuit. The measurement circuit includes a compensator that compensates for the effect of changes in ambient temperature to the resistance of the active element without compensating for heat lost by thermal conduction from the active element.

Abstract: A gas detection sensor permits precise measurement of the concentration of flammable gas in a detection or subject gas and the concentration of oxygen in a detection gas containing flammable gases. In the sensor, the heating of the sensor by contact catalytic reaction of flammable gas gives off a detection signal of the flammable gas. The gas detection sensor has a first detection sensor including a diaphragm having a platinum coat on a side which the flowing detection gas comes in contact with, and a thermocouple having respective ends of two different metals placed close to each other and fixed on the side of the diaphragm not coming in contact with the flowing detection gas and which is heated by the contact catalytic reaction of flammable gas. A second detection sensor similar to the first detection sensor detects the temperature of the flowing detection gas.

Abstract: A base is provided with a concave and three leads, and the central lead is bent to the side opposite to the concave, and the other leads are bent to the side of the concave. A central electrode of a sensor element is attached to the central lead and the bottom of the concave and a coil serving as both a heater and an electrode is attached to the other leads to support the sensor element on a small base at four points.

Abstract: A method of and apparatus for detecting if a MOS gas sensor has been poisoned, the sensor having a sensor element for sensing a target gas and having a heater configured to heat the sensor element in response to a voltage being applied to the heater, the heater having an operating temperature which is selectively maintained by applying a first voltage thereto. The method includes reducing the voltage from the first voltage; and sensing a change in resistance of the sensor element, responsive to the reduction of the voltage from the first voltage, and comparing sensed changes with expected changes. The apparatus includes circuitry configured to reduce the voltage from the first voltage; and the same or different circuitry senses a change in resistance of the sensor element which is responsive to the reduction of the voltage from the first voltage, and compares sensed changes with expected changes.

Abstract: A gas sensor for detection of oxidizing and reducing gases, including O2, CO2, CO, and H2, monitors the partial pressure of a gas to be detected by measuring the temperature rise of an oxide-thin-film-coated metallic line in response to an applied electrical current. For a fixed input power, the temperature rise of the metallic line is inversely proportional to the thermal conductivity of the oxide coating. The oxide coating contains multi-valent cation species that change their valence, and hence the oxygen stoichiometry of the coating, in response to changes in the partial pressure of the detected gas. Since the thermal conductivity of the coating is dependent on its oxygen stoichiometry, the temperature rise of the metallic line depends on the partial pressure of the detected gas. Nanocrystalline (<100 nm grain size) oxide coatings yield faster sensor response times than conventional larger-grained coatings due to faster oxygen diffusion along grain boundaries rather than through grain interiors.

Abstract: The invention includes systems and methods which allow reactivation of supported noble metal catalysts. The method involves heating the catalyst in the presence of a gaseous hydrocarbon in the absence of oxidizing agents. Systems of the invention provide for in situ reactivation of catalytic material.

Abstract: A heater pattern for a heater of a gas sensor in which a temperature profile is manipulated utilizes a thermistor element arranged in an electrically serial configuration and disposed on a substrate. The thermistor element is arranged so as to define an edge pattern extending about a perimeter of the substrate and a center pattern serially connected to the edge pattern. The center pattern extends over a portion of the substrate that is intermediate the perimeter of the substrate. In a preferred embodiment, the thermistor element is screen printed onto the substrate to a thickness of about 5 microns to about 50 microns, and preferably to a thickness of about 10 microns to about 40 microns. The edge and center patterns are furthermore preferably formed of materials having differing coefficients of thermal resistivity, e.g., platinum and platinum/palladium blends.

Abstract: In this method of analyzing a gas mixture containing at least one inflammable gas to determine its explosibility, a resistive heating element (15) is energized in an analysis enclosure (12) communicating with the gas mixture to be analysed to burn the gas mixture in the enclosure, an electrical signal (S) at the terminals of the resistive element (15) is measured during combustion, and the explosibility of the gas mixture is determined from a comparison of values of the signal measured during a transient phase in which the concentration of the inflammable gas in the gas mixture is falling. The measurements taken during the transient phase are taken at times chosen to obtain, for different inflammable gases, substantially identical measurement signals for concentrations corresponding to identical explosibilities.

Abstract: A stable sensor designed to detect accurately the total NOx concentration under 100 ppm in terms of the NO gas concentration is made up of a first cell and a second cell with a gas diffusion aperture provided between the two cells. The first cell has a partition wall of a substrate of oxygen ion conductor containing zirconia as the main component and permitting a gas to be detected to enter the zirconia substrate; oxygen pumping electrodes are also formed on the first cell substrate which functions to expel oxygen in an atmosphere of the first cell to the outside and to reduce NO.sub.2 of the NOx gas to be detected to NO gas.

Abstract: A multilayered gas sensor for detecting the presence of gases in air. In particular, sensors are described for sensing hydrocarbons and nitrogen oxides. An additional feature of the invention is to provide a device that is suitable for sensing gases in the harsh environment of an automobile exhaust system. The device features a ceramic substrate and a glass layer to adhere a catalyst support to the substrate. A catalyst layer of either platinum or rhodium is deposited on the catalyst support and a thermally sensitive resistor element detects reactions of hydrocarbons or nitrogen oxides on the corresponding catalyst.

Abstract: A differential scanning microcalorimeter produced on a silicon chip enables microscopic scanning calorimetry measurements of small samples and thin films. The chip may be fabricated using standard CMOS processes. The microcalorimeter includes a reference zone and a sample zone. The reference and sample zones may be at opposite ends of a suspended platform or may reside on separate platforms. An integrated polysilicon heater provides heat to each zone. A thermopile consisting of a succession of thermocouple junctions generates a voltage representing the temperature difference between the reference and sample zones. Temperature differences between the zones provide information about the chemical reactions and phase transitions that occur in a sample placed in the sample zone.

Abstract: In order to determine a concentration of a gas mixture, especially a hydrogen concentration of a containment atmosphere of a nuclear power station, a temperature change resulting from a catalytic reaction is measured. The gas mixture is diluted with a motive gas of known composition. The dilution is carried out by a jet pump.

Abstract: The invention includes systems and methods which allow reactivation of supported noble metal catalysts. The method involves heating the catalyst in the presence of a gaseous hydrocarbon in the absence of oxidizing agents. Systems of the invention provide for in situ reactivation of catalytic material.

Abstract: The selectivity of response of resistive gas sensors to specific gases or vapors is improved by the selection of specified gas-sensitive materials which are not previously known for the applications described, which include detection of hydrocarbons in the presence of CO, H.sub.2 S, SO.sub.2, chlorine, NO.sub.2, CO.sub.2 (especially in low concentrations), CFC's, ammonia, free oxygen by determination of partial pressures, and numerous organic gases and vapors.

Abstract: A sensor housing (10) for directing the flow of a gas over two sensitive regions (53, 54) of sensing device (52) includes an inner shroud (12) surrounding the sensing device (52). The inner shroud (12) is inserted into an outer shroud (14), such that a plurality of gas channels (44) are formed between the inner shroud (12) and the outer shroud (14). In operation, a gas enters through inlet orifices (28) in the outer shroud (14) and travels through the gas channels (44) to the proximal end (26) of the inner shroud (12). The flow direction of the gas is then reversed and the gas passes through an inner chamber (50) and over sensitive regions (53), (54) located on the surface of the sensing device (52). Vacuum pressure created at an outlet hole (46) located at a distal end (35) of the outer shroud (14) draws the gas out of the inner chamber (50) and return the gas to the exterior of the sensor housing (10).

Abstract: A sensor is provided for precisely measuring the composition of mixtures of hydrogen and oxygen gas. The sensor has an active surface, at which hydrogen and oxygen are catalytically converted into water. A transport inhibiting barrier is disposed on the active surface. The heat released during the conversion is measured, and is indicative of the mixture composition.

Abstract: A combustible gas sensor having a pair of temperature sensor sections is here disclosed. One of the pair of temperature sensor sections is covered with porous oxidizing catalytic layers (23, 24) for oxidizing a combustible gas, and the other is not covered with the oxidizing catalyst layers. In the one temperature sensor section, the combustible gas is burned, and in the other temperature sensor section, the temperature of a gas to be measured is compensated. The temperature sensor sections each comprises temperature sensitive portions (13, 14) made of a dense ceramic material, resistors (21, 22) buried therein and having a positive resistance temperature coefficient, current leads (31, 32, 41, 42) and voltage leads (33, 34, 43, 44). A method for measuring the concentration of the combustible gas by the use of this combustible gas sensor is also disclosed.

Abstract: A catalytic detector for a flammable gas comprises a substrate and a sensing structure suspended from the substrate. The sensing structure has a combined heating element and temperature sensing element in the form of a layer-deposited electrically conductive track terminating in at least two electrically conductive bridging leads. A catalytic bead is deposited over the temperature sensing element and that portion of the substrate which is directly beneath the sensing structure is etched away so as to isolate thermally the sensing structure with the temperature sensing structure being supported by the bridging leads. The electrically conductive track is sandwiched between a substrate adhesion layer for facilitating adhesion of the conductive track and a superstrate diffusion barrier layer. The invention extends to a method of manufacturing a gas detector and a sensing structure.

Abstract: A chemical sensor couples a material that changes temperature in response to a chemical condition with an oscillator. The oscillator is coupled to the material to detect the change in temperature in the material so that the frequency of the oscillator changes in correspondence with the change in temperature as an indication of the chemical condition.

Abstract: A semiconductor chemical sensor device (2) comprises a sensitive layer (4) for detecting specific chemicals and a heater for heating the sensitive layer, which is formed by a heater portion (6) of a conductive layer (8) in the semiconductor chemical sensor device (2). The semiconductor chemical sensor device (2) further comprises a thermocouple (12) for detecting the temperature of the sensitive layer (4), the thermocouple comprising a P/N junction (14) formed as part of or adjacent the heater portion (6) of the conductive layer (8) such that a signal developed across the P/N junction (14) is representative of the temperature of the sensitive layer (4).

Abstract: The invention is a sensing method and an oxygen sensor for detecting a change of oxygen partial pressure in an ambient atmosphere through a change of a measurable physical property of a sensing material. The sensor includes a sensing material selected from metal or its oxides which, when at an elevated temperature and exposed to a gas containing a changing partial pressures of oxygen, is capable of changing from one metal or metal oxide phase to another such oxide phase and vice versa. Associated with such phase change is a change in a measurable physical property of the material. The sensor also includes an electrical heating source, connectable to a power source, maintaining a temperature gradient across the sensing material since it is critical that the sensing material exist in at least two phases during active sensing.

Abstract: A high-temperature gas sensor for the detection of the heat tone of combustible gases includes a semiconducting ceramic layer with thermistor properties. The semiconducting ceramic layer is formed of an oxide ceramic semiconducting material having a defined crystalline structure and a thermistor characteristic of high sensitivity. A process for the manufacture of the high-temperature gas sensor includes sintering a loosely structured layer of powder particles of an oxide semiconductor with both a defined composition and high sinter activity for achieving a required high porosity of a semiconducting ceramic layer with thermistor properties.

Abstract: A method and apparatus is provided for modulating flux of combustibles reacting with oxygen impinging on a calorimetric gas sensor. The method includes the steps of enclosing a sensing element and a reference element of a calorimetric gas sensor with an apparatus having at least one aperture to allow combustibles to enter and impinge on the sensing element and reference element, periodically restricting the aperture of the apparatus to modulate the flux of combustibles entering at a predetermined frequency to produce an AC output signal from the calorimetric gas sensor, and measuring the sensor output at the frequency at which the aperture is restricted.

Abstract: A self-contained, integrated-structure, miniature, electrochemical-type oxygen sensor is described which uses an oxygen ion conducting solid electrolyte. An encapsulated metal-metal oxide reference electrode on one surface of the solid electrolyte provides a reference oxygen pressure. A sensing electrode is placed on the other surface. The voltage developed between the reference electrode and the sensing electrode is indicative of the oxygen content of the fluid the sensing electrode is contacting.

Abstract: A substrate carrying a first electrode and a second electrode, the first and second electrodes being disposed adjacent to one another, the first electrode being disposed between the substrate and a gas-sensitive component, the gas sensitive component comprising an n-type semiconductor, the gas-sensitive component having a resistance that is gas-dependent and temperature-dependent, and the second electrode being disposed between the substrate and a non-gas-sensitive component, the non-gas-sensitive component comprising a n-type semiconductor and a p-type semiconductor, the non-gas-sensitive component having a resistance that is temperature-dependent and that is not gas-dependent and wherein the n-type semiconductor of the non-gas-sensitive component is Ga.sub.2 O.sub.3 and the p-type semiconductor of the non-gas-sensitive component is ZrO.sub.2.

Abstract: A catalytic differential gas combustible microcalorimeter sensor for monitoring the exhaust gas conversion for monitoring the exhaust gas conversion efficiency of a catalytic converter. The catalytic calorimetric sensor disclosed includes a sol-gel processed washcoat and sol-processed catalytically active metal particles. Sol-gel processing creates a washcoat with high surface area and controlled porosity which increases the sensitivity, durability, and reproducibility of the resultant sensor.

Abstract: An NOx sensor for an exhaust gas is made from .beta.-Nb.sub.2 O.sub.5 as a primary component and TiO.sub.2 as a subsidiary component. The TiO.sub.2 content is in a range of 0.1% by weight .ltoreq.TiO.sub.2 .ltoreq. 20% by weight. In place of TiO.sub.2, Ru may be used in the NOx sensor. The Ru content is in a range of 0.1% by weight .ltoreq.Ru.ltoreq. 10% by weight. Thus, the NOx sensor has an excellent NOx adsorbing ability and is higher in sensitivity to NOx in an exhaust gas.

Abstract: A multilayered ceramic integrated sensor 200 for monitoring auto exhaust gases is capable of existing in the relatively harsh environments of the exhaust stream of an internal combustion engine. The integrated sensor 200 may include discrete devices such as an oxygen sensor 104, a hydrogen sensor 206, an NO.sub.x sensor 208, and a carbon monoxide sensor 210. The device 200 may further include a temperature sensor 202 as well as total combustion calorimetric sensor 102. The multilayered ceramic integrated sensor may be fabricated from a plurality of layers of ceramic material disposed in stacked relationship with respect to one another.

Abstract: In a gas sensor for sensing reducing or oxidizing gases which comprises a semiconductive metal oxide film, there are provided stripe-like outer electrodes which define therebetween a continuous surface area and stripe-like inner electrodes which extend between, and parallel to, the outer electrodes so as to divide the continuous surface area into longitudinal segments which have different properties with respect to reducing or oxidizing gases such that different conductivity changes are generated for the different segments upon exposure to oxidizing or reducing gases.

Abstract: A gas sensor for detecting the presence of gases in air. In particular, sensors are described that have a compound catalytic support structure and are suitable for sensing hydrocarbons and nitrogen oxides. The device features a ceramic substrate having a temperature sensitive resistor on one surface. A mixture of ceramic particles and glass powder are applied over the substrate and resistor and fired so that the glass flows and adheres the ceramic particles to the substrate. A catalyst layer of either platinum or rhodium is deposited on the catalyst support and a thermally sensitive resistor element detects reactions of hydrocarbons or nitrogen oxides on the corresponding catalyst. The invention is suitable for sensing gases in the harsh environment of an automobile exhaust system.

Abstract: In an oxygen analyzer for an industrial process, an automotive type oxygen sensor has a sensor element assembly with an outer thin walled shield containing insulation and surrounding the sensor element of the automotive type oxygen sensor.