Abstract: An ammonium gas sensor is provided. The ammonium gas sensor includes: a solid electrolyte layer having oxygen ion conductivity; a detection electrode formed on one surface of the solid electrolyte layer; a reference electrode that is a counter electrode of the detection electrode; a selective reaction layer covering the detection electrode; and a protection layer covering the selective reaction layer and made from a porous material; wherein the detection electrode includes a noble metal as a main component; the selective reaction layer includes oxide represented by AxMyOz as a main component, where A is one or more kind(s) of metal, M is vanadium, tungsten, or molybdenum and x, y, z are atomic ratios; and the protection layer includes the oxide that is in an amount smaller than a content of the oxide included in the selective reaction layer.

Abstract: A gas sensor contains a sensor element for detecting the concentration of a particular gas component in a measurement gas and a housing for supporting the sensor element inside, and the sensor element has a rectangular solid structure of a solid electrolyte body containing a ceramic material. In the gas sensor, four edges of the solid electrolyte body are beveled over the entire length thereof to form eleventh to fourteenth chamfered portions corresponding to the four edges.

Abstract: A gas sensor, that represses a manufacturing cost, obtains high responsiveness and can effectively reduce adhesion of water to a sensor element and intrusion of water into the sensor element, is provided. In the gas sensor that has the sensor element mainly containing a solid electrolyte with oxygen ion conductivity and a protective cover arranged to surround the sensor element and detects a predetermined gas component in a measurement gas, the protective cover includes an inner protective cover that is formed into a bottomed cylindrical shape, has a plurality of inner gas distributing holes formed in two rows on its side surface in a longitudinal direction of the sensor element and surrounds one front end of the sensor element, and an outer protective cover that is formed into a bottomed cylindrical shape, has a plurality of outer gas distributing holes on its side surface and surrounds the inner protective cover.

Abstract: In a gas sensor 100, a ratio A2/A1 defined by a ratio of an opening area A1 per first inner gas hole and an opening area A2 per second inner gas hole 138a is set to higher than or equal to 0.9 and lower than or equal to 3.8 and, more preferably, to higher than or equal to 1.5 and lower than or equal to 1.9. Accordingly, adhesion of water to a sensor element 110 can be sufficiently prevented. In addition, a ratio B2/B1 defined by a ratio of a total opening area B1 of the first inner gas holes to a total opening area B2 of the second inner gas holes 138a is set to higher than or equal to 0.85 and, more preferably, higher than or equal to 1.5. Accordingly, adhesion of water to the sensor element can be more reliably, effectively prevented.

Abstract: A gas sensor including a detection element having a stacked structure configured to detect a specified gas component contained in a gas to be detected. The detection element includes: a sensing portion including one or more solid electrolyte layers containing a first material as a main component and having a first surface and a second surface opposite the first surface; a first portion stacked on the first surface and including one or more first base layers containing a second material as a main component different from the first material; and a second portion stacked on the second surface and including one or more second base layers containing the second material. A total thickness of the one or more second base layers in a stacking direction is not less than 80% but not more than 120% of a total thickness of the one or more first base layers.

Abstract: A gas sensor and nitrogen oxide sensor, which, when fitted to the exhaust system of an internal combustion engine, can suppress the influence of harmful substances contained in a measurement gas and can prevent the reduction in sensitivity over time. A harmful substance-trapping layer is formed at a gas inlet for introducing a to-be-measured gas from an external space into an internal space, and in a buffering space formed between diffusion resistance portions. In a trap-formed portion of a gas passage in which the harmful substance-trapping layer is formed, the measurement gas can pass in an amount of 80% or more of when the harmful substance-trapping layer is not formed in the trap-formed portion. A diffusion resistance is attained in the diffusion resistance portions; a harmful substance is trapped in the harmful substance-trapping layer; and the measurement gas is allowed to flow into a detection electrode side.

Abstract: A gas sensor including a pump electrode and a method for manufacturing a conductive paste for forming the pump electrode. When the pump electrode constituting an electrochemical pump cell for adjusting an oxygen partial pressure inside a gas sensor to measure a concentration of a gas component in a measurement gas by a current-limiting method is formed of a cermet of a noble metal and an oxide having oxygen ion conductivity, the noble metal contains a first noble metal having a catalytic activity, and a second noble metal having a catalytic activity suppressing ability to suppress the catalytic activity of the first noble metal with respect to an oxide gas except for oxygen, and an abundance ratio of the second noble metal with respect to the first noble metal in a particle surface of the first noble metal existing in the pump electrode is to be 0.01 to 0.3.

Abstract: A sensor detection controller is used in combination with a capacitive sensor that is mounted on a seat of a vehicle in such a manner that a capacitance of the capacitive sensor changes according to whether the seat is occupied. The sensor detection controller has a fault detection mode and a normal detection mode. The sensor detection controller includes a signal source for applying an amplitude signal to the capacitive sensor, a switch for switching a signal path, through which the amplitude signal is applied, between the fault detection mode and the normal detection mode, a signal detector for detecting a change in a voltage or a current of the amplitude signal when the amplitude signal is applied, and an impedance member connected to the signal path.

Abstract: A laminated gas sensor element including a detection element including a solid electrolyte body having a pair of electrodes formed thereon laminated together with a heater element. A porous protection layer is formed on at least a distal end portion of the laminated gas sensor element which is to be exposed to a gas to be measured. The surface of the porous protection layer has 10 or more small pores each having a diameter of 1 ?m to 5 ?m inclusive and an aspect ratio of 0.5 to 2.0 inclusive within an area measuring 50 ?m×50 ?m, and one to less than 20 large pores each having a diameter of 8 ?m to 20 ?m inclusive and an aspect ratio of 0.5 to 2.0 inclusive within an area measuring 100 ?m×100 ?m. Also disclosed is a method for manufacturing the laminated gas sensor.

Abstract: This invention provides a gas sensing device and gas sensor including a porous portion in which a first porous portion absorbs phosphorus and silicone sufficiently so as to suppress generation of clogging in a second porous portion meeting demands for intensifying the performance and accuracy of a gas sensor, so that the accuracy of detection of air-fuel ratio is further improved.

Abstract: There is provided a gas sensor, which includes a sensor element extending axially of the gas sensor and having a gas sensing portion at a front end thereof and an electrode portion at a rear end thereof, a cylindrical metal shell retaining therein the sensor element with the gas sensing portion and the electrode portion protruding from front and rear ends of the metal shell, respectively, and having a flange portion and a rear end portion located on a rear side of the flange portion, a cylindrical protection cover having a front end fitted onto the rear end portion of the metal shell so as to cover the electrode portion and a weld joint through which the entire circumference of the front end of the protection cover is joined through the metal shell. The weld joint extends from an end face of the protection cover to the metal shell.

Abstract: A gas sensor for detecting a predetermined gas component in a measurement gas includes a sensor element in which an opening of a first gas inlet and an opening of a second gas inlet for introducing the measurement gas from an outside are provided at one end. The openings are elongated and substantially rectangular. A sum of sizes in a lateral direction of the openings is greater than or equal to 8 ?m and less than or equal to 60 ?m, and a sum of areas of the openings is greater than or equal to 0.02 mm2 and less than or equal to 0.1 mm2. The sizes in the lateral direction and the areas of the openings are set to be within a preferable range so that the water droplets attached on the forward end surface can be prevented from entering into the sensor element through the openings.

Abstract: An exhaust gas sensor that simultaneously exhibits enhanced water soak resistance and functionality, that is multilayered and exposed to a space in an exhaust path. The exhaust gas sensor includes: an electrolyte layer, positioned between an exhaust electrode and an atmosphere electrode; an atmospheric layer formation layer formed toward the atmosphere electrode to form an atmospheric layer to which the atmosphere electrode is exposed; a porous diffusion resistance layer formed toward the exhaust electrode to control flow rate of an exhaust gas reaching the exhaust electrode; and a porous trap layer formed to cover the entire section exposed to the space in the exhaust path. The trap layer includes a first trap layer, which covers a region near a gas inlet/outlet section of the diffusion resistance layer, and a second trap layer, which covers another region that covered by the first trap layer. The first trap layer is thinner than the second trap layer.

Abstract: In one embodiment, a protective coating for an electrode of a sensor is described, the protective coating comprising an annealed catalyst, said annealed catalyst comprising at least one metal that has been subjected to thermal energy that is at least equivalent to or greater than that received from calcining the at least one metal for 24 hours at a temperature of 930 degrees C in air. In another embodiment, the annealed catalyst will comprise at least one metal that has been subjected to thermal energy that is equal to or less than that received from calcining the at least one metal for 24 hours at 1030 degrees C in air. In one exemplary embodiment, the annealed catalyst will comprise at least one metal that has been subjected to thermal energy that is equal to that received from calcining the at least one metal for 24 hours at 980 degrees C in air.

Abstract: A sensor for specifying a concentration of a predetermined gas component in a measurement gas on the basis of a current flowing in an electrolyte by decomposition of the predetermined gas component, includes an internal space; a reference gas space; a pumping cell capable of pumping out oxygen in the internal space by applying a predetermined voltage between a first electrode and a second electrode; and a measuring cell including third and fourth electrodes and measuring a current flowing when a voltage is applied between the third electrode and the fourth electrode; wherein the first electrode is formed of porous cermet consisted of a noble metal and an oxygen ion conductive solid electrolyte, and the porosity of the first electrode is greater than or equal to 10% and less than or equal to 50%.

Abstract: A gas sensing member has a unit structure and a porous protective layer disposed on the unit structure. The unit structure has a solid electrolyte body, a gas measurement electrode disposed on a surface of the body and exposed to a measured gas entering at a gas inlet, a reference gas electrode disposed on another surface of the body and exposed to a reference gas, and a heater disposed close to the body. The heater has a heater substrate and heating elements disposed in the heater substrate. The heating elements heat the body. The heater substrate has side corner areas placed on side corners of the unit structure and being adjacent to the heating elements. The protective layer is disposed on the gas inlet such that the side corner areas are not covered with the protective layer and are directly exposed to the measured gas.

Abstract: A gas sensing element is disclosed as having a measuring gas chamber to which measuring gases are admitted, a diffusion resistance portion for introducing measuring gases to the measuring gas chamber under diffusion resistance, a sensor cell for detecting a specified gas concentration of measuring gases, and an oxygen pump cell for adjusting an oxygen concentration in the measuring gases. The sensor cell includes a measuring electrode, placed facing the measuring gas chamber, and a reference electrode formed in pair with the measuring electrode. The oxygen pump cell includes an inner pump electrode placed facing the measuring gas chamber, and an outer pump electrode formed in pair with the inner pump electrode. The diffusion resistance portion is placed in an area inside of external end walls of the inner pump electrode to be exposed to the measuring gas chamber.

Abstract: An ammonia gas sensor including a reference electrode (320) is formed on the back surface of a solid electrolyte member (310), and a detection electrode (335) is formed on the front surface of the solid electrolyte member (310). A detection lead (350) is provided on the front surface of the solid electrolyte member (310) such that the detection lead (350) is connected to the detection electrode (335). An insulating layer (340), (380) is provided between the detection lead (350) and the solid electrolyte member (310), or on the detection lead (350).

Abstract: A gas sensor (200) has a gas sensor element (10) including a first measurement chamber (16); a first pumping cell (11) having a first interior pump electrode (11c) and its counterpart electrode (11b); a second measurement chamber (18); a second pumping cell (13) that has a second interior pump electrode (13b); and a beater (50). The heater (50) has a lead section (50a); a first resistance portion (50bx) having a higher resistance than the lead portion (50a); and a main heating portion (50k) having a second resistance portion (50by) having a higher resistance than the first resistance portion (50bx) disposed at a leading end side in a longitudinal direction relative to a leading end of the first resistance portion (50bx). The second interior pump electrode (13b) is located within the first resistance portion (50bx) in the longitudinal direction.

Abstract: A laminated gas sensor element extending in a longitudinal direction and having a detection part including a plate-shaped element body which has a heater layer having an embedded resistance heating body and a detection layer laminated to the heater layer and having a vertical surface along a lamination direction and a horizontal surface perpendicular to the lamination direction; and a porous protective layer coating the vertical surface and the horizontal surface of the element body constituting the detection part, wherein a thickness of the protective layer formed on the vertical surface is thicker than a thickness of the protective layer formed on the horizontal surface.

Abstract: A plural-cell gas sensor including at least an oxygen pump cell (40) comprising a solid electrolyte ceramic layer; an internal space (210) formed between the cells; and a heater substrate (190) arranged on the side of the oxygen pump cell; the heater substrate heating the oxygen pump cell that pumps oxygen out of the internal space.

Abstract: A measuring sensor is described for determining a physical property of a measured gas, especially for determining the oxygen concentration or the pollutant concentration in the exhaust gas of internal combustion engines, which has a sensor element that is exposable to the measured gas which is at least partially coated with a protective layer that protects against harmful components in the measured gas. In order to achieve producing a “contamination protection”, that is cost-effective from a manufacturing technology point of view, particularly against silicon compounds and phosphorus compounds, the protective layer (26) is made of highly active ?- or ?-aluminum oxide (Al2O3) having additives of compounds of the alkaline metals group, the alkaline earths group, the IV B subgroup or the lanthanides group.

Abstract: There is provided a gas sensor, including a gas sensing film formed of an oxide semiconductor material and a gas-permeable protection layer formed of oxide particles and arranged on the gas sensing film. The oxide particles of the protection layer have an average particle size of 500 nm or smaller.

Abstract: A sensor element is provided for determining a physical property of a measuring gas, especially of the concentration of at least one gas component in the measuring gas, which has at least one ceramic layer, a diffusion barrier adjoining the at least one ceramic layer and at least one electrode that is exposed to the measuring gas diffusing through the diffusion barrier. In order to reduce the production variations with respect to the static pressure dependence and the limiting current of the diffusion barrier), the proportions of silicon in the diffusion barrier and in the at least one ceramic layer are approximately equal and differ by not more than 1 wt. %.

Abstract: A technology which makes it possible to prolong the service life of a porous electrode constituted by a sintered body of an electrode metal material and a ceramic material, and the service life of an NOx sensor element having the porous electrode. The porous electrode is produced so as to have a total pore volute of at least 0.013 ml/g and a peak pore diameter of at least 0.31 ?m as measured by mercury penetration method, by a process wherein a composition which includes the electrode material and the ceramic material and to which a vanishable solid material that vanishes by firing is formed into a thin film, which is then fired to form the sintered body which consists of the electrode material and the ceramic material and which has a multiplicity of pores formed as a result of vanishing of the vanishable solid material.

Abstract: A gas sensor element includes a solid electrolyte body having oxygen ion conductivity, a pair of measurement and reference electrodes respectively provided on an opposite pair of first and second surfaces of the solid electrolyte body, a porous diffusion-resistant layer through which a measurement gas is introduced to the measurement electrode, and a protective layer. The protective layer is provided to cover, at least, an outer surface of the porous diffusion-resistant layer through which the measurement gas flows into the diffusion-resistant layer. The protective layer is hydrophilic at room temperature and water-repellent at high temperatures at which the solid electrolyte body can be activated.

Abstract: A gas sensor element is disclosed which includes a solid electrolyte body, a measurement electrode, a reference electrode, a porous diffusion-resistant layer, a catalyst layer, and a plurality of protective layers. The catalyst layer is provided on an outer surface of the porous diffusion-resistant layer through which a measurement gas is introduced to the measurement electrode. The catalyst layer is comprised of a noble metal catalyst and catalyst-supporting particles. The protective layers are provided in layers on the catalyst layer and comprised of oxide particles. The average particle diameter of the catalyst-supporting particles of the catalyst layer is less than or equal to the average particle diameter of the oxide particles of the one of the protective layers which adjoins the catalyst layer. The further the protective layers are from the catalyst layer, the larger the average particle diameters of the oxide particles of the protective layers are.

Abstract: Electrodes comprising ruthenium oxide nanoparticles are disclosed. The ruthenium oxide nanoparticles are located within the electrode or as a coating thereon. The electrode is especially suited for measuring the presence and/or concentration of nitric oxide in a sample.

Abstract: A gas sensor is equipped with a cover assembly made up of an outer cover and an inner cover in which a gas sensor element is disposed. The outer cover has an outer gas inlet and an outer gas outlet formed closer to a top end of the cover assembly than the outer gas inlet. The inner cover has an inner gas inlet formed closer to the top end of the cover assembly than the outer gas inlet. The inner gas inlet is oriented to minimize the entry of drops of water having entered along with a gas to be measured into the inner cover to avoid splashing of the gas sensor element with the water.

Abstract: A gas sensor element having an element body, the element body including: a ceramic heater having ceramic layers and a heater element embedded in the ceramic layers; and a solid electrolyte layer including a detection section covered by a pair of electrodes, the solid electrolyte layer being laminated together with the ceramic heater. Furthermore, the element body has a width at a front portion including the detection section smaller than at a rear portion, and at least both side edge faces of the front portion of the element body are covered with a porous layer.

Abstract: A gas sensor element has a solid electrolyte body of oxygen ionic conductivity, a target gas electrode and a reference gas electrode formed on both surfaces of the solid electrolyte body, respectively, a porous diffusion resistance layer, and a catalyst support trap layer. The porous diffusion resistance layer covers the target gas electrode and through which target gases to be measured are passing. The catalyst support trap layer is formed on the outer surface of the porous diffusion resistance layer and supports noble metal catalyst. In the gas sensor element, the noble metal catalyst is made of platinum, rhodium, palladium supported in the catalyst support trap layer. In particular, an addition amount of palladium in the total amount of the noble metal catalyst is within a range of 2 to 65 wt %.

Abstract: An oxygen sensor generating an accurate output concerning low-concentration exhaust gas positioned downstream of a three-way catalyst. The oxygen sensor includes an exhaust gas side electrode exposed to an exhaust gas; a reference gas side electrode exposed to a reference gas serving as a reference for oxygen concentration; and an electrolyte positioned between the exhaust gas side electrode and the reference gas side electrode. Further, a reduction mechanism positioned toward a front surface of the exhaust gas side electrode ensures the ratio of the amount of exhaust gas introduced to the exhaust gas side electrode to the amount of an exhaust gas flow to the outside of the oxygen sensor is smaller than the ratio of the amount of exhaust gas introduced to an electrode for the air-fuel ratio sensor to the amount of an exhaust gas flow to the outside of the air-fuel ratio sensor.

Abstract: Apparatus and methods for measuring NOx concentrations are disclosed. One method includes the steps of providing a gas stream having a NO concentration and a NO2 concentration, wherein a sum of the NO concentration and the NO2 concentration is a total NOx concentration; contacting the gas stream with a first zirconium oxide based oxygen sensor at a first temperature to achieve a first NO:NO2 equilibrium at the first temperature; contacting the gas stream with a second zirconium oxide based oxygen sensor at a second temperature to achieve a second NO:NO2 equilibrium at the second temperature; and determining the total NOx concentration by measuring a response of the first zirconium oxide based oxygen sensor to achieve the first NO:NO2 equilibrium and a response of the second zirconium oxide based oxygen sensor to achieve the second NO:NO2 equilibrium. The second temperature is different than the first temperature.

Abstract: A gas sensor including a gas detecting element extending in a longitudinal direction and in which a plurality of ceramic layers are stacked, and wherein a detecting portion is provided at a leading end side of the gas detecting element, the gas detecting element including: a first ceramic layer; a second ceramic layer; a first through-hole conductor; a first peripheral portion; a second through-hole conductor; a second peripheral portion; and an opening all as defined herein, wherein the first peripheral portion and the second peripheral portion respectively have mutually overlapping adhered portions and separated portions opposing one another through a gap continuing to the opening, and a relationship L1>S1 is satisfied, where L1 represents a maximum length of the adhered portion, and S1 represents a maximum length of the separated portion.

Abstract: A sensor element to determine the temperature or the oxygen concentration of an exhaust gas of an internal combustion engine includes a first solid electrolyte film, a second solid electrolyte film, and a diffusion barrier disposed in a layer plane between the first and the second solid electrolyte film. A gas-impermeable or at least largely gas-impermeable cover layer is provided locally on the diffusion barrier, so that in the regions in which the cover layer is provided on the diffusion barrier, diffusion of the measured gas into or out of the diffusion barrier is at least largely prevented. A corresponding method for manufacturing a sensor element includes ablating a diffusion barrier using a laser in order to adjust the diffusion resistance of the diffusion barrier. A cover layer that, after a sintering process, is gas-impermeable or at least largely gas-impermeable is applied onto a side of the diffusion barrier that faces toward a measured gas located outside the sensor element.

Abstract: A sensor element for the determination of the concentration of gas components in a gas mixture, particularly of the concentration of gas components in the exhaust of internal combustion engines, with two electrodes, that together with a solid electrolyte constitute a pumping cell, whose outer pumping electrode is exposed to the gas mixture by way of a porous protective layer, and with a reference electrode, which is disposed on the solid electrolyte and is exposed to a reference gas, and which with a solid electrolyte and a Nernst electrode constitutes a concentration or Nernst cell, is thereby characterized in that at least periodically the Nernst voltage between the outer pumping electrode and the Nernst electrode is tapped and analyzed.

Abstract: A turbine of a turbocharger is disposed on an exhaust passage. An air-fuel ratio sensor is disposed downstream of and in proximity to the turbine. An element of the air-fuel ratio sensor is positioned on or near the axis of an exhaust port of the turbine. A whirling flow of an exhaust gas in the same direction as a turbine wheel rotates is produced immediately after the exhaust port of the turbine, so that the whirling flow of the exhaust gas can centrifuge condensed water in the exhaust gas. The exhaust gas contacts the element near the axis of the exhaust port where there is substantially no condensed water, thus preventing the element from being wetted with water or cracked.

Abstract: The present invention provides, as one aspect, a gas sensor element including a solid electrolytic substance having a bottomed cylindrical shape and oxygen ion conductivity, a reference electrode arranged on an inner side surface of the solid electrolytic substance, a measuring electrode arranged on an outer side surface of the solid electrolytic substance, and a protective layer which covers the outer side surface of the solid electrolytic substance together with the measuring electrode and which allows gas to be measured to pass through the protective layer, wherein an end side of the gas sensor element is formed of a leg portion whose profile line is straight on an axial cross section and a bottom portion whose profile line is curved, and the film thickness of the protective layer of the bottom portion is larger than the film thickness of the protective layer of the leg portion.

Abstract: A gas sensor having a gas sensor element which includes: a reference electrode; a solid electrolyte layer having oxygen ion conductivity; a detection electrode; and an electrode-protecting layer covering the detection electrode. The electrode-protecting layer is a porous body carrying catalytic metal, and includes: a detection electrode side portion having a catalytic metal loading ratio of more than 0% by weight and not more than 0.005% by weight; and a surface side portion provided closer to the outer surface of the electrode-protecting layer than the detection electrode side portion, the surface side portion having a catalytic metal loading ratio of 0.01% by weight or more.

Abstract: A gas sensor comprising a first measuring chamber for introducing a gas to be measured, a second measuring chamber for detection of the gas to be measured, and as pump cells a first pump cell having a pair of pump electrodes, and a second pump cell having a measuring electrode and an auxiliary pump electrode, wherein a porous alumina sintered body having communicating pores of 500-1100 ? in average pore diameter and 6-16% in porosity is formed as an electrode protective layer on the surface of at least the measuring electrode of the second pump cell in such a manner that the alumina sintered body covers the measuring electrode. The gas sensor can be use for long period of time because of the protective layer.

Abstract: Disclosed herein is an ammonia sensor element comprising an ammonia selective sensor electrode, a reference electrode, a solid electrolyte in ionic communication with the ammonia selective sensor electrode and the reference electrode, and a protective layer disposed on the ammonia selective sensor electrode, comprising a porous portion comprising an ammonia-inert material. A method of making an ammonia gas sensor element comprises disposing an ammonia selective sensor electrode on and in ionic communication with a solid electrolyte, disposing a reference electrode on and in ionic communication with the solid electrolyte, and disposing a protective layer comprising a porous portion comprising an ammonia-inert material on the ammonia selective sensor electrode.

Abstract: A total NOx sensor with minimal interferences from CO and O2 includes a yttria-stabilized zirconia (YSZ) pellet and a Pt-loaded zeolite Y layer. Furthermore, three platinum wires are attached to the YSZ surface which operate as the working, counter and reference electrode. A potentiostat is connected to the electrodes to maintain a fixed potential between the reference and working electrode. The potentiostat then monitors the relationship between time and current through the counter electrode.

Abstract: A ceramic laminate body, a gas sensor element employing such a ceramic laminate body and related manufacturing method are disclosed as including first and second ceramic sheets, made of material compositions different from each other, and an intermediate bonding layer, bonding the first and second ceramic sheets to each other so as to form a closed hollow space between the first and second ceramic sheets. The intermediate bonding layer has a multilayer structure including first and second unit intermediate layers laminated on each other such that innermost end portions of the first and second unit intermediate layers are displaced from each other to adapt a difference in degreasing contraction rates of associated component parts.

Abstract: A gas sensor is constructed as follows. A protector (4) covering around a gas sensing element (2) has an inner hollow-cylindrical portion (6) and an outer hollow-cylindrical portion (7) that is provided coaxially with the inner hollow-cylindrical portion (6) with an air space (8) in between. Outer-wall gas inlet openings (13) are formed in the outer hollow-cylindrical portion (7), and guiding bodies (10) extending inward are attached to the outer-wall gas inlet openings (13). Inner-wall gas inlet openings (11) are formed in the inner hollow-cylindrical portion (6) at positions nearer to the gas sensing element (2) than the outer-wall gas inlet openings (13). A side wall (9) face of the inner hollow-cylindrical portion (6) opposite the outer-wall gas inlet openings (13) is formed so as to be parallel to a side wall (12) of the outer-hollow cylindrical portion (7) or so as to have a slop-like shape with a diameter enlarging in the axial direction toward a bottom wall (17) of the protector (4).

Abstract: A sensor element for determining the concentration of gas components in gas mixtures, e.g., for determining the oxygen concentration in exhaust gases of combustion engines, includes: at least one electrochemical measurement cell that encompasses a first and a second electrode in contact with a solid electrolyte material; a heating element for heating the sensor element to operating temperature; and a cavity integrated into the sensor element. The cavity exhibits, in at least one region close to the lateral delimiting surfaces of the cavity, a diameter that is greater than zero and smaller than the diameter in its central region.

Abstract: There is provided a gas sensor, including a gas sensing film formed of an oxide semiconductor material and a gas-permeable protection layer formed of oxide particles and arranged on the gas sensing film. The oxide particles of the protection layer have an average particle size of 500 nm or smaller.

Abstract: A sensor element for the determination of the concentration of gas components in a gas mixture, particularly of the concentration of gas components in the exhaust of internal combustion engines, with two electrode, that together with a solid electrolyte constitute a pumping cell, whose outer pumping electrodes is exposed to the gas mixture by way of a porous protective layer, and with a reference electrode, which is disposed on the solid electrolyte and is exposed to a reference gas, and which with a solid electrolyte and a Nernst electrode constitutes a concentration or Nernst cell, is thereby characterized in that at least periodically the Nernst voltage between the outer pumping electrode and the Nernst electrode is tapped and analyzed.

Abstract: In an oxygen sensor for installation in the exhaust gas system of a vehicle for detecting a concentration of NOx in exhaust gas downstream from a catalytic converter, in which the exhaust gas is passed through a protective layer to an electrode disposed at one side of a solid electrolyte in a sensor element of the oxygen sensor, the protective layer is formed with a combination of values of thickness and porosity which provide improved sensitivity in detecting low levels of NOx in the exhaust gas.

Abstract: A gas sensor includes a sensing element, a housing, a metal cover, and an oxide layer. The sensing element generates a signal indicative of an oxygen concentration in a measurement gas. The housing holds therein the sensing element with a portion of the sensing element protruding outside of the housing. The metal cover surrounds the portion of the sensing element and is to be exposed the measurement gas. The metal cover has formed therein a gas passage through which the sensing element is also to be exposed to the measurement gas. The oxide layer is formed on at least a surface of the metal cover. With the oxide layer, during operation, at least the metal cover is prevented from being oxidized by the oxygen contained in the measurement gas. Consequently, the oxygen concentration in the measurement gas can be accurately determined based on the signal generated by the sensing element.

Abstract: A gas sensor element including: a solid electrolyte layer having a first surface and a second surface; a first electrode formed on the first surface of the solid electrolyte layer; a second electrode formed on the second surface of the solid electrolyte layer; and an insulating layer provided between the first electrode and the first surface of the solid electrolyte layer. The insulating layer covers an outer edge of the first electrode and has an opening through which a portion of the first electrode is exposed. The opening has an area that is smaller than that of the second electrode, and is provided at a position opposite the second electrode to form a detection portion constituted by the portion of the first electrode exposed through the opening, the second electrode and the solid electrolyte layer.