Abstract: A first electrode (133) has an exposure portion (133b) exposed to a second measuring chamber (160), and a connection portion (133d) which is disposed at a position not exposed to the second measuring chamber (160) and is connected to the first lead (137) and which is a portion of the first electrode (133) located most distant from the second measuring chamber (160). The entire connection portion (133d) is located in a region A1 which extends from the second measuring chamber (160) over a distance of 1.0 mm or less.

Abstract: A gas sensor (100) includes an oxygen pump cell (135) and an oxygen-concentration detection cell (150) laminated together with a spacer (145) interposed therebetween. The spacer (145) has a gas detection chamber (145c) which faces electrodes (137, 152) of the cells (135, 150). The oxygen-concentration detection cell (150) produces an output voltage corresponding to the concentration of oxygen in the gas detection chamber (145c). The oxygen pump cell (135) pumps oxygen into and out of the measurement chamber (145c) such that the output voltage of the oxygen-concentration detection cell (150) becomes equal to a predetermined target voltage. A leakage portion mainly formed of zirconia is disposed between which electrically connects the oxygen-concentration detection cell (150) and the oxygen pump cell (135).

Abstract: A gas sensor (200) includes a gas sensor element (10) extending in the direction of an axis O, and a housing (50) made of metal, radially surrounding the gas sensor element, and adapted for inserting at least partially into a sensor-mounting hole (350) of a mounting body (300). The gas sensor (200) further includes a resin member (60, 61) which radially surrounds the housing at least partially and having a contact portion (C) in contact with the housing that is at least partially disposed axially frontward with respect to the outer surface of the mounting body (300) around the sensor-mounting hole, and a heat sink member (80) that is in contact with the housing at an axial position the same as or located frontward of the axial position of the front end of the contact portion.

Abstract: A gas sensor is provided with a multilayer body of solid electrolyte layers, a measurement electrode, a reference electrode, a reference gas introduction layer, a detection unit and a heater. The reference electrode and the measurement electrode are formed directly on the same first solid electrolyte layer. Thus, heat from the heater is transferred from a third substrate layer to the first solid electrolyte layer, and also to the reference electrode and the measurement electrode through the same first solid electrolyte layer. The reference electrode is covered with a reference gas introduction layer, formed of a porous body. The transference of heat from the heater to the reference electrode through the reference gas introduction layer is smaller than the transference of heat from the heater to the reference electrode through the first solid electrolyte layer on which the reference electrode is formed directly.

Abstract: A gas sensor is disclosed. The gas sensor includes a gas sensing electrode and a counter electrode disposed within a housing, and respective conductors that connects the gas sensing electrode and the counter electrode to a sensing circuit. The housing includes walls defining a cavity containing electrolyte in fluid communication with the gas sensing electrode and counter electrode and wherein the walls further comprise one or more coatings or second layers superimposed on the walls. The one or more coatings or second layers have a lower water vapor transport rate than that of the walls, such that, in use, water vapor transport between the electrolyte and atmosphere through the walls of the housing is reduced.

Abstract: A sensor control apparatus includes: a gas sensor including an oxygen concentration detection cell having a first solid electrolyte body, a reference electrode and a detection electrode, and a heater; an electric current supply unit that supplies electric current to the oxygen concentration detecting cell; an activation determination unit; a heater control unit that sets a first target temperature equal to or higher than an activation determination temperature when the activation determination unit determines that the temperature of the gas sensor is equal to or higher than the activation determination temperature; an automatic stop detection unit; and a first temperature switching unit that controls electric current supplied to the heater such that the target temperature of the heater is switched to a second target temperature different from a temperature at which blackening is generated in the first solid electrolyte body when an automatic stop is detected.

Abstract: Devices and methods are disclosed that can adjust a hydration level in an electrochemical sensor or an instrument which includes such a sensor. The device can include a chamber which can, at least in part, surround an inflow port of the sensor. An adjacent reservoir of water can provide a source of water vapor which can be infused into the sensor.

Abstract: A sensor element is formed by cutting a laminated body and heating with the cutting taking place in a state where a difference in resistance on sides of a cutting component is as small as possible. That is, a uniform cutting is where resistance added to both sides of the cutting component is substantially the same. When uniform cutting cannot be performed, a nonuniform cutting in a state where resistance added to both sides of the cutting component is different is performed. Consequently, a surface perpendicular to a longitudinal direction of the sensor element is trapezoidal.

Abstract: A crimp contact, a gas sensor including the crimp contact for outputting a signal from a sensing portion of a sensor element to an external device, and a method for manufacturing the crimp contact. The crimp contact includes a barrel portion crimped so as to fix a plurality of lead core wires (16) of an electrical lead connected to the external device. A hold portion constituting the barrel portion is formed such that the lead core wires 16 of the electrical lead are disposed in an U-shaped hold portion 77 so as to be crimped between an anvil 120 and a crimper 121. An outer surface of the U-shaped hold portion 77 has a plating layer 85 thereon to thereby constantly secure slidability between a sliding face of the crimper 121 and the outer surface of the U-shaped hold portion 77.

Abstract: A gas sensor control system for a gas sensor having a first, a second, and a third cell. The second cell produces a second cell electric current indicating the concentration of oxygen in gas in which the amount of oxygen has already been controlled by the first cell. The third cell produces a third cell electric current indicating the concentration of a preselected component of the gas in which the amount of oxygen has already been controlled by the first cell. A second cell circuit converts the second cell electric current into a voltage as a second cell current-measured value. A current adjuster produces a flow of an adjustment current as a function of the second cell current-measured value so that a third cell circuit converts the third cell electric current minus the adjustment current into a voltage as representing the concentration of the preselected component of the gas.

Abstract: A gas sensor element includes a main body and a protective layer. The main body has four plane portions and four corner portions each of which is formed between one adjacent pair of the plane portions. The four corner portions include a pair of first corner portions that are formed on a porous diffusion-resistant layer side in a lamination direction of the main body and a pair of second corner portions that are formed on a heater layer side in the lamination direction. The protective layer is comprised of an inner protective layer that covers at least the first corner portions of the main body and an outer protective layer that covers the entire outer periphery of the main body and the inner protective layer. The protective layer has a larger average thickness at the first corner portions than at the plane portions of the main body.

Abstract: A control apparatus (100) for a gas sensor (10) which includes a cell (2) composed of a solid electrolyte body and a pair of electrodes provided thereon. The control apparatus includes voltage application means (70) for applying a single pulse voltage to the cell over a constant energization time T; first-output-value obtaining means 70 for obtaining a first output value Vri1 from the cell when a first time t1 shorter than the constant energization time has elapsed; second-output-value obtaining means (70) for obtaining a second output value Vri2 from the cell when a second time t2 shorter than the constant energization time but longer than the first time has elapsed; and deterioration-degree detection means 70 for detecting the degree of deterioration of the cell on the basis of a difference ?Vri between the second output value and the first output value.

Abstract: A gas sensor element has a first cell, a second cell, and a solid electrolyte layer having proton conductivity commonly used by the first cell and the second cell. The first cell has a first cathode and a first anode exposed to the target detection gas containing hydrogen atoms. The second cell has a second anode, a second cathode, and a shield layer with which the second anode is covered. A voltage is supplied to the first and second cells. A gas concentration of the target detection gas is calculated on the basis of a difference between a current of the first cell and a current of the second cell because the current in the first cell is a sum of proton conductivity current and an electron conductivity current. The current in the second cell is an electron conductive current only.

Abstract: A device for determining the CO concentration in a gas containing hydrogen is provided, including a detection electrode in contact with the gas, and a counter electrode, each being in contact with an electrolyte; a current source to deliver a current with a predetermined intensity between the detection electrode and the counter electrode so as to generate, at the detection electrode, an electric potential fluctuating between two threshold values due to the adsorption and desorption of the CO at the detection electrode; a device for measuring the potential; and a calculating device to determine the CO concentration, connected to the current source and to the device for measuring the potential, for calculating a characteristic parameter of the fluctuations of the potential, and for determining the CO concentration from the calculated characteristic parameter and the intensity of the applied current.

Abstract: A gas sensor including a gas sensor element that extends in an axial direction and has a detection section at a front-end side thereof, and an electrode pad at a rear-end side thereof; a connection terminal that is electrically connected to the electrode pad; and an insulated separator that extends along the axial direction and has an inserting hole into which the connection terminal is inserted. An element side section is arranged within the inserting hole and is connected the electrode pad, and an external circuit side section extends further to the outside in a diametrical direction than an outer surface of the separator through one or more first bending sections from the element side section.

Abstract: A gas sensor control apparatus is provided which controls an operation of a gas sensor made up of a solid electrolyte body and a pair of electrodes to output a signal indicating the concentration of a given gas component contained in gas. The gas sensor control apparatus includes a constant current circuit that is connected electrically to one of the electrodes of the gas sensor and supplies a constant current thereto and a controller. The controller supplies a constant current to the gas sensor so that it flows from one of the electrodes to the other in a selected direction, thereby changing a response time the gas sensor takes to react to a change in concentration of the gas component. This results in an increased accuracy, for example, in controlling an air-fuel ratio of a mixture to an internal combustion engine in an engine control system.

Abstract: A gas sensor comprises a substrate layer; a pair of interdigitated metal electrodes, said electrodes include upper surfaces, the electrodes selected from the group consisting of Pt, Pd, Au, Ir, Ag, Ru, Rh, In, Os, and their alloys. A first layer of solid electrolyte staying in between electrode fingers and partially on said upper surfaces of said electrodes, said first layer selected from NASICON, LISICON, KSICON and ??-Alumina. A second layer of metal carbonate(s) as an auxiliary electrolyte engaging said upper surfaces of the electrodes and the first solid electrolyte. The metal carbonates selected from the group consisting of the following ions Na+, K+, Li+, Ag+, H+, Pb2+, Sr2+, Ba2+, and any combination thereof.

Abstract: To provide a gas sensor which can stably carry out a securement of an electric continuity between a sensor element and a contact member. A contact member in which an electric connection to a sensor element is obtained by pinching and fixing the sensor element in an inserting port formed by a pair of housing members includes a constraint member which is provided in an outer periphery of a pair of housing members. The constraint member constrains a displacement of a pair of housing members within a predetermined range before the sensor element is pinched and fixed by a pair of housing members, and exists in a state of being pinched between the annular member and a pair of housing member without generating any reaction force with respect to the external force, after the sensor element is pinched and fixed.

Abstract: A gas sensor including a sensor element constituted by an oxygen-ion conductive solid electrolyte as a main component and detecting a predetermined gas component in a measurement gas includes: an external communication part having an opening opened to the outside, and introducing the measurement gas from the outside under a predetermined diffusion resistance; an internal space communicating with the external communication part; a first electrode formed on a surface of the internal space; a second electrode formed in a space different from the internal space; and a pumping cell operable to pump out oxygen existing in the internal space when a predetermined voltage is applied between the first electrode and the second electrode. The thickness of the external communication part is 50% or more and 100% or less of the thickness of the internal space.

Abstract: The disclosure provides a material with the general formula Sr1-xAxSi1-yGeyO3-0.5x, wherein A is K or Na, including mixtures thereof, and wherein 0?y?1 and 0?x?0.4. In a specific embodiment, 0?y?0.5. In another specific embodiment, 0?y?0.1 and 0?x?0.4. In another specific embodiment 0.9?y?1 and 0?x?0.25. The material may be a single-phase polycrystalline solid having a monoclinic crystal structure. The material may have an oxide-ion conductivity (?o) greater than or equal to 10?2 S/cm at a temperature of at least 500° C. The material may be formed into a planar or tubular membrane or a composite with another solid member. The material may be used as the electrolyte in a fuel cell or a regenerative or reverse fuel cell, as an oxygen sensor, or as an oxygen separation membrane. The material may also be used as a catalyst for oxidation of an olefin or for other purposes where oxide-ion conductivity is beneficial.

Abstract: A gas sensor element includes an insulating ceramic base, a solid electrolyte body, and a heating element. The solid electrolyte body is disposed in an opening of the insulating ceramic base and has a measuring electrode affixed to one of major surfaces thereof and a reference electrode affixed to the other major surface. The measuring electrode is exposed to gas to be measured. The reference electrode is exposed to a reference gas. The heating element works to activate the solid electrolyte body and is mounted on one of opposed surfaces of the insulating ceramic base on the same side as the major surface of the solid electrolyte body on which the reference electrode is disposed. Specifically, the insulating ceramic base is located between the solid electrolyte body and the heating element, thereby ensuring a desired degree of electric insulation between the heating element and the reference electrode.

Abstract: An inter-cylinder air-fuel-ratio imbalance determination apparatus includes an air-fuel-ratio sensor in an exhaust passage of an engine. The air-fuel-ratio sensor functions as a limiting-current-type wide range air-fuel-ratio sensor when a voltage is applied, and functions as a concentration-cell-type oxygen concentration sensor when no voltage is applied. The determination apparatus causes the air-fuel-ratio sensor to function as the limiting-current-type wide range air-fuel-ratio sensor, and executes air-fuel ratio feedback control on the basis of the output value of the air-fuel-ratio sensor. When an imbalance determination parameter is obtained, the determination apparatus causes the air-fuel-ratio sensor to function as the concentration-cell-type oxygen concentration sensor, and obtains, as the imbalance determination parameter, a value corresponding to the differentiated value of the output value of the air-fuel-ratio sensor.

Abstract: A sensor includes an oxygen pump cell; an oxygen pump chamber; an emf cell; a reference chamber providing a fluid connection to the reference gas; gas channels in fluid communication with the pump and emf electrodes, the reference gas comprising reformate produced by a fuel reformer fueled by an air-fuel gas mixture having an air-fuel ratio; a reformer electronic control module; a sensor electronic control module; a heater; a temperature sensor disposed in communication with the heater and the sensor control module for maintaining the sensor at a desired operating temperature; a closed loop controlled operation amplifier in electrical communication with the sensor, whereby the oxygen pump cell provides sufficient oxygen ions to oxidize an incoming diffusion-limiting fuel flux to the emf cell and maintain a constant emf at the emf cell, and wherein a current value represents an equivalent to the air-fuel ratio of the air-fuel gas mixture.

Abstract: A cathodic material for use in an electrochemical sensor comprising: a carbonaceous material and an oxygen reduction catalyst associated with the carbonaceous material; and wherein the cathodic material does not materially exhibit catalytic activity for the oxidation of carbon monoxide. Associated electrochemical sensors may include an anode and cathode that are disposed upon the same or opposite sides of an ion exchange membrane and/or exposed to the same or different gaseous environments.

Abstract: An explosion-proof sensor for detecting combustible gases is provided with a glass seal (9) for establishing an electrically conductive connection with the interior of the housing. The sensor is improved in terms of the pressure resistance of the housing. The glass seal (9) has a bending-resistant casting compound (16, 17, 18) mechanically stabilizing the glass seal (9) on at least one side.

Abstract: A deterioration signal generation device for an oxygen sensor having a power supply different than a power supply connected to an external device, including a connection unit for electrically connecting the ground lines of the respective power supplies; a first acquisition unit for electrically connecting to a first output line at a reference potential side and to a second output line at a sensor potential side of the oxygen sensor, to obtain first and second potentials, respectively; an operation unit that calculates a first differential value between the first and second potentials; a processing unit that performs an operation on the first differential value; a second acquisition unit that acquires a third potential of a first input line at a reference potential side of the external device; and an output unit that generates the deterioration signal by superposing the second differential value on the third potential.

Abstract: A deterioration signal generation device for an oxygen sensor having a power supply different than a power supply connected to an external device, including a connection unit for electrically connecting the ground lines of the respective power supplies; a first acquisition unit for electrically connecting to a first output line at a reference potential side and to a second output line at a sensor potential side of the oxygen sensor, to obtain first and second potentials, respectively; an operation unit that calculates a first differential value between the first and second potentials; a processing unit that performs an operation on the first differential value; a second acquisition unit that acquires a third potential of a first input line at a reference potential side of the external device; and an output unit that generates the deterioration signal by superposing the second differential value on the third potential.

Abstract: In a sensor control device, it is determined whether a gas sensor is activated. A concentration control is performed at an elapse timing which elapses by a first constant time from an activation timing at which the gas sensor is determined to be activated. A preliminary control is performed in at least a partial period between the elapse timing and a start timing at which a drive control is started.

Abstract: A gas sensor including a plate-shaped laminate disposed in a housing and fixed thereto via an element passage member and formed by laminating a gas sensor element and a heating element. The gas sensor element includes a plate-shaped solid electrolyte member, and a pair of detection electrodes formed on front and back surfaces thereof and constituting, in cooperation with the solid electrolyte member, a detection section for detecting the concentration of a specific gas. Insulating substrates mainly composed of alumina are provided on opposite sides of the laminate in the laminating direction. Coating layers mainly composed of a first material higher in toughness than alumina are formed on at least portions of outer surfaces of the insulating substrates in the laminating direction, the portions facing the element passage member. The coating layers are not formed on surfaces of the laminate parallel to the laminating direction.

Abstract: A gas sensor control apparatus includes a heater regulating section to control the supply of electricity to a heater included in a gas sensor, an impedance sensing section to sense an impedance of a cell of the gas sensor, and an impedance condition examining section to examine whether the sensed impedance is greater than or equal to a predetermined abnormality judging threshold. The control apparatus further includes a voltage condition examining section to examine whether a maximum effective voltage is applied to the heater, when the impedance is above the predetermined abnormality judging threshold, a duration measuring section to examine whether an application time duration of the maximum effective voltage becomes equal to or longer than a predetermined heater overheat preventing time, and a voltage decreasing section to decrease the heater application voltage to such a lower effective voltage as to hold the temperature of the cell higher than or equal to 500° C.

Abstract: A gas sensor including a sensor element constituted by an oxygen-ion conductive solid electrolyte as a main component and detecting a predetermined gas component in a measurement gas includes: an external communication part having an opening opened to the outside, and introducing the measurement gas from the outside under a predetermined diffusion resistance; an internal space communicating with the external communication part; a first electrode formed on a surface of the internal space; a second electrode formed in a space different from the internal space; and a pumping cell operable to pump out oxygen existing in the internal space when a predetermined voltage is applied between the first electrode and the second electrode. The thickness of the external communication part is 50% or more and 100% or less of the thickness of the internal space.

Abstract: A method and device allow the determination of the concentrations of a plurality of gas species in a gas mixture based on the output signals from a plurality of gas sensors, each of which is sensitive to a plurality of gas species in the gas mixture. The method includes measuring the response of each sensor at a number of levels of each gas in the mixture, determining a mathematical representation of the response characteristics of each sensor, and using the mathematical representation to determine gas concentrations from sensor readings.

Abstract: Described herein are substrates, sensors and systems related to measuring the concentration of an analyte such as hydrogen ion in a sample. Redox active moieties whose reduction and/or oxidation potentials are sensitive to the presence of an analyte are immobilized onto a surface of an electrode. Immobilized redox active moieties whose reduction and/or oxidation potential are insensitive to the analyte can be used for reference. Voltammetric measurements made using such modified surfaces can accurately determine the presence and/or concentrations of analytes in a sample of interest. The electrochemical sensors of the invention are robust and can be made so as not to require calibration or re-calibration.

Abstract: An electrochemical sensor includes a polymeric housing and at least a first electrode within the housing. The first electrode includes an electrochemically active surface. The electrochemical sensor further includes a first connector in electrically conductive connection with the first electrode. The first connector includes a first extending member formed from a conductive loaded polymeric material. The first extending member is formed such that an interior thereof comprises conductive elements within a matrix of the polymeric material so that the interior is electrically conductive and an exterior surface thereof comprises the polymeric material and is less conductive than the conductive interior. The conductive interior of the first extending member is in electrically conductive connection with the first electrode. The first connector further includes a first extending conductive element in electrical connection with the conductive interior.

Abstract: An array-type sensor that senses NH3 includes non-Nernstian sensing elements constructed from metal and/or metal-oxide electrodes on an O2 ion conducting substrate. In one example sensor, one electrode may be made of platinum, another electrode may be made of manganese (III) oxide (Mn2O3), and another electrode may be made of tungsten trioxide (WO3). Some sensing elements may further include an electrode made of La0.6Sr0.4Co0.2Fe0.8O3 and another electrode made of LaCr0.95Mg0.05O3.

Abstract: The disclosed invention relates to an amperometric gas sensor for measuring the concentration of an analyte, comprising: a solid support; and a working electrode in contact with the solid support; wherein the analyte comprises a dopant which when in contact with the solid support increases the electrical conductivity of the solid support. A sterilization process employing the amperometric gas sensor is disclosed.

Abstract: An electro-chemical sensor for methane is described having a catalyst to react methane or other low molecular weight hydrocarbons and a detector to detect the turnover or reaction rate and using such information to determine the concentration of the methane or other low molecular weight species. The sensor is preferably used for measurements in a wellbore.

Abstract: A gas sensor including a detection element (6), wherein a detection electrode (63D) and a reference electrode (62B) are provided on an outer circumferential surface (61A) and an inner circumferential surface, respectively, of a closed-bottomed tubular solid electrolyte body (61). A heater inserted into the tubular hole of the detection element (6) is in contact with the reference electrode at point Q. The detection electrode (63D) is partially formed in the vicinity of a position which faces the point Q with the solid electrolyte body (61) intervening therebetween, and the surface area of the detection electrode (63D) is 8% to 20% of the surface area of a detection portion (64).

Abstract: The purpose of the invention is to provide a method for accurately quantifying a chemical substance by a substitutional stripping voltammetry technique. A method is provided for quantifying a chemical substance contained in a sample solution, and the method comprises preparing a measurement system. The measurement system comprises a pair of working electrodes (a first and a second electrodes), a counter electrode, and a gel-coated electrode. This gel-coated electrode comprises an electrode surface, a stripping gel, and a protection gel, and the protection gel covers the stripping gel.

Abstract: There is provided a gas sensor element, including a solid electrolyte layer, a pair of sensor electrodes arranged on a front side of the solid electrolyte layer, a pair of sensor leads arranged on a rear side of the solid electrolyte layer and connected to the respective sensor electrodes; and insulating layers, one of which is arranged between one of the sensor leads and the solid electrolyte layer and the other of which is arranged between the other sensor lead and the solid electrolyte layer. The sensor electrodes have rear end portions located on the insulating layers and overlapping front end portions of the sensor leads, respectively. The sensor leads are denser than the sensor electrodes and have front ends located in the same positions as or positions rear of front ends of the insulating layers, respectively. There is also provided a gas sensor with such a gas sensor element.

Abstract: A sensor element for determining a gas component in a measuring gas includes a first and a second electrode, a solid electrolyte situated between the electrodes, a heater having a heating element, and an insulation surrounding the heating element, wherein the heating element has a meander pattern having a first external heating area, a second external heating area, a first internal heating area, and a second internal heating area.

Abstract: A gas sensor is provided. The gas sensor includes a gas-sensitive layer which changes in its characteristic properties upon contact with a detectable gas. The gas-sensitive layer has as the main sensitive part, a polycrystalline layer composed of a large number of uniform nano-size microcrystal grains which join together in the planar direction.

Abstract: A gas sensor includes an inner electrode formed on an inner surface of a base body. The inner electrode has an inner sensing portion formed in a gas contact inner region such that the inner sensing portion is located on the whole of a heat-facing area of the gas contact inner region facing a heating portion in a radial direction of the base body, a terminal contact portion formed in a rear end region such that the terminal contact portion is located in at least a part of the rear end region in a circumferential direction of the base body and a lead portion formed only on a part of the inner surface of the base body in the circumferential direction of the base body so as to connect the inner sensing portion and the terminal contact portion to each other.

Abstract: A planar device includes a heating circuit that is disposed between ceramic layers and co-fired with the ceramic. The heating circuit comprises palladium, and the co-firing of the palladium and ceramic is performed in an oxidizing atmosphere. The formation of defects in the planar device that would otherwise be induced as a result of the palladium oxidizing during the co-firing process is prevented by control of the firing profile, by the geometry of the pattern of the heating circuit, and/or by modifying the palladium to reduce its tendency to oxidize.

Abstract: Disclosed herein is a method of making a sensing element comprising forming an electrically conductive element, wherein the sensing element comprises a metal selected from the group consisting of Pd and alloys and combinations comprising Pd; and wherein the electrically conductive element is thermally stable at temperatures as high as 1,200° C.

Abstract: A gas sensor element includes a basal body, at least one solid electrolyte portion and a pair of electrodes. The basal body has a bottomed tubular shape and is made of an electrically insulative ceramic material. The basal body has a side wall and a bottom wall. The at least one solid electrolyte portion is formed in the bottom wall or the side wall of the basal body. The pair of electrodes are opposed to each other with the at least one solid electrolyte portion interposed therebetween. The difference in surface level between the basal body and the at least one solid electrolyte portion at a boundary therebetween is less than or equal to 30 ?m.

Abstract: An electrochemical gas sensor includes: a disc-shaped metal bottom member; a cylindrical metal side member that extends along the axial direction of the bottom member to surround the bottom member; a ring-shaped polymer gasket that includes an opening in the center and in which both sides of the opening each have an L-shaped member in cross section, with one section of the L-shaped member being in contact with the inner side of the side member and the other section of the L-shaped member being in contact with the bottom member; a gas sensor body that is located in the opening of the gasket and whose bottom surface is in contact with the bottom member and that includes a pair of electrodes and a solid electrolyte membrane or a separator retaining a liquid electrolyte; and a metal cover that is in contact with the top surface of the gas sensor body.

Abstract: A defect detection method for a sensor in which a fixing member provides a seal between a sensor element and tubular metallic members, the method being capable of detecting breakage of a conductor caused by breakage of the element.

Abstract: A NOx sensor includes a sensor element equipped with first and second pumping cells to define first and second measurement chambers. The first pumping cell exerts an oxygen pumping action against the first measurement chamber to adjust the oxygen concentration in the gas under measurement within the first measurement chamber to a given level. The second pumping cell exerts an oxygen pumping action against the second measurement chamber to produce a pumping cell current according to the NOx concentration in the gas under measurement. When the moisture content of the gas under measurement changes from 2 vol % to 8 vol %, the NOx sensor allows a variation of NOx concentration detection value based on the pumping cell current in such a manner that the NOx concentration detection value reaches a transient peak value of 20 ppm or smaller and converges to ±5 ppm of a reference value within 5 seconds.

Abstract: A deterioration diagnosis device, which performs a deterioration diagnosis of a catalyst, includes an exhaust-gas sensor provided downstream of the catalyst in a flow direction of exhaust gas such that an output value of the exhaust-gas sensor is used at least in the deterioration diagnosis. The deterioration diagnosis device further includes the constant current supply portion which applies a voltage to a sensor element of the exhaust-gas sensor to change an output characteristic of the exhaust-gas sensor, a response-time detection portion which detects a response time required for the output value of the exhaust-gas sensor to change from a rich threshold to a lean threshold, a response-time correction portion which controls the constant current supply portion to change the output characteristic of the exhaust-gas sensor so as to shorten the response time when the response time is longer than a predetermined reference time.