Abstract: A gas sensor for measuring an amount of a measurement gas component, including a solid electrolyte having an internal space, a gas-introducing port for introducing measurement gas from an external space into the internal space, diffusion rate-determining means between the internal space and the gas-introducing port, and inner and outer pumping electrodes for pumping-processing oxygen contained in the measurement gas. The diffusion rate-determining means includes slits each having, when viewed in a plane substantially perpendicular to a longitudinal extension axis thereof, two dimensions, with at least one dimension of each slit being not more than 10 microns.

Abstract: A sensor for determining a physical property such as the concentration of a gas component or the temperature of a measuring gas, e.g., the exhaust gas of internal combustion engines, has a sensor element which is secured in a housing and is surrounded at an end section on the measuring gas side by a protective tube and surrounded at an end section on the connection side by a protective sleeve, and also has a radially projecting flange for securing the sensor on a sealing seat formed on a measuring gas duct. To reduce manufacturing costs, the flange is molded onto the protective tube as one piece. The protective tube is manufactured as a deep-drawn part, and a trimming edge remaining after deep drawing on the end side is used as a securing flange.

Abstract: An improved structure of a protective cover assembly of a gas sensor is provided. The protective cover assembly is of a double-walled structure made up of an inner and an outer cylindrical cover with gas holes. A sensing element is disposed within the inner cover. At least one of the gas holes of the outer cover partially faces a side wall of the inner cover. A top end surface of the inner cover lies within a range defined between opposed portions of a perimeter of the at least one of the gas holes of the outer cover closest to a top and a base end of the cover assembly, respectively. This structure works to avoid breakage of the sensing element arising from wetting with water and to improve a response rate of the gas sensor.

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.

Abstract: An insulation bushing assembly for use with an exhaust gas sensor. The insulation bushing assembly includes an insulation bushing having a passageway defining a surface, and a contact plate assembly having a contact plate coupled with the insulation bushing. A resilient member extends from the contact plate and into the passageway. The resilient member is engageable with the surface of the passageway such that the member is deflected by the surface from an undeflected position with respect to the contact plate to a deflected position with respect to the contact plate to retain the contact plate assembly in engagement with the bushing.

Abstract: A protective cover of a gas sensor includes an inner protective cover which covers at least an end portion of a sensor element, an outer protective cover which covers the inner protective cover, and an intermediate protective cover which is installed between the inner protective cover and the outer protective cover. A1/A2?1 provided that A1 represents a total opening area of the inner gas inlet holes provided for the inner protective cover, and A2 represents a total opening area of the outer gas inlet holes provided for the outer protective cover.

Abstract: An improved structure of a gas sensor is provided which is designed to minimize thermal damage to a water-repellent filter installed in a base end portion of the gas sensor. The gas sensor has an elastic seal installed in an opening of the base end portion of the gas sensor and an air cover assembly made up of a main cover and a filter cover. The filter cover is crimped to form at least two necks which establish joints of the filter cover to the main cover through the water-repellent filter. At least one of the necks is used to retain the elastic seal within the main cover. This structure locates the water-repellent filter farther away from the top of the gas sensor exposed to intense heat, thereby minimizing the thermal deformation or deterioration of the water-repellent filter.

Abstract: A sensor for measuring a physical property of a measuring gas, in particular the oxygen concentration or the temperature in the exhaust gas of an internal combustion engine in a motor vehicle, has a housing, a measuring element whose end section protrudes from the housing, a connector plug mounted on the end section, and a housing shell covering the end section and connector plug with a radial clearance, one shell end of the housing shell being attached to the housing and the other shell end being sealed. To prevent electromechanical breakage in the sensor in the event of extreme vibration stresses or accelerations of the vehicle, the free space within the housing shell is completely filled with a non-conductive granulate.

Abstract: A gas sensor comprises a cylindrical metallic housing, a sensor element having at a front end thereof a sensing portion and disposed axially in the housing with the sensing portion protruded from a front end of the housing, a sensor terminal fitted to a rear end of the sensor element to produce a signal output from the sensing portion, a first protective cover attached to a front end portion of the housing to cover the sensing portion and a second protective cover attached to a rear end portion of the housing to cover the sensor terminal. The first and second protective covers includes attachment portions attached around the front and rear end portions of the housing, respectively. At least one of the attachment portions of the first and second protective covers has a lower hardness than a remaining portion of the protective cover.

Abstract: The invention includes a method and apparatus for a chromatography system having a chromatographic column for separating gases in a mixture from one another and an electrochemical gas sensor coupled to the chromatographic column for detecting a gas being emitted from the column. The electrochemical gas sensor further includes a substrate having a surface for depositing electrodes thereon, an ionomer membrane in contact with the surface, an electrode in contact with the surface, and an opening in the ionomer membrane in a location proximate to the electrode for permitting a gas to diffuse through the opening to simultaneously contact the electrode and the ionomer membrane within the opening.

Abstract: A detecting element is described, in particular a gas sensor for detecting the concentration of a gas component in a measuring gas, including a sensor element which is exposable to the measuring gas and has a connecting end section which is contacted by connecting cables and is exposed to a reference gas atmosphere. The end section is accommodated in a protective sleeve having a radial opening over which a gas-permeable diaphragm covering the at least one radial opening is provided, the diaphragm, in turn, being engaged by a clamping sleeve having at least one radial opening. To avoid the axial penetration of liquids between the clamping sleeve and the diaphragm, which would cause the detecting element to malfunction, the clamping sleeve is caulked axially above and below the radial openings. Both caulking zones are designed in such a way that the diaphragm is compressed with increasing force from the inner caulking edges facing each other to the outer caulking edges facing away from each other.

Abstract: An improved manufacturing method for a gas sensor is provided which is capable of establishing a required hermetic seal in a body of the gas sensor. The method includes preparing a sensor assembly including a housing, an air cover, an insulation porcelain, and a sensor element, pressing the air cover against the housing to fit an end of the air cover on an end of the housing to form an overlap thereof, and welding the air cover to the housing over the overlap. The welding is accomplished while pressing the air cover against the housing, thereby compressing an elastic member in the air cover to establish a hermetic seal between the sensor element and the housing.

Abstract: A gas sensor (1a) having a laminate including an alumina substrate (11) having a heating resister (115) embedded in the alumina substrate (11); a first oxygen-ion conductive solid electrolyte layer (131) containing zirconia and alumina and partly constituting an oxygen-detecting cell (13) and the first solid electrolyte layer (131) being laminated with said alumina substrate (11); a second oxygen-ion conductive solid electrolyte layer (121) containing zirconia and alumina and partly constituting an oxygen-pumping cell (12); an ion-leakage preventing ceramic spacer (143) for preventing oxygen-ions from leaking from the second oxygen-ion conductive solid electrolyte layer (121) to the first oxygen-ion conductive solid electrolyte layer (131), the spacer (143) being laminated between the first and second oxygen-ion conductive solid electrolyte layers (131, 121); and a gas-diffusion space (141) formed between an electrode (133) of the oxygen-detecting cell (13) and an electrodes (126) of the oxygen-pumping cell (

Abstract: A gas sensor equipped with a protective gas cover which defines therein a gas chamber to which a sensor element is exposed. The protective gas cover has gas inlet holes through which gas to be measured is admitted. The protective cover also has dimples formed adjacent the gas inlet holes, respectively, which are designed to avoid a direct hit of a flow of the gas on the sensor element and minimize the concentration of thermal stress around the gas inlet holes. In an alternative form, the gas inlet holes are formed in the dimples, respectively.

Abstract: A ceramic heater is provided which may be employed in a gas sensor. The ceramic heater includes a heating element disposed inside a ceramic body, a connector assembly, and a cover coating. The connector assembly consists of an external terminal, a connector terminal, and a metallic joint layer. The external terminal is affixed to an outer surface of the ceramic body in electrical connection with the heating element. The joint layer is formed on the external terminal to establish an electrical joint between the external terminal and the connector terminal. The cover coating is wrapped over a surface of the connector assembly and made of a metallic material containing a main component of one of Au, Pt, and Cr, thereby ensuring a corrosion resistance of the connector assembly.

Abstract: A heater is inserted into an inside chamber of a sensor element until a tip end of the heater is surely brought into contact with a bottom surface of the inside chamber. Next, a metallic holder is attached on an outside surface of the heater. Then, the metallic holder is slid along the outside surface of the heater toward the bottom surface of the sensor element to engage the metallic holder with an edge of the sensor element.

Abstract: A gas sensor comprising: a gas sensor element extending in an axial direction; a cylindrical metal shell enclosing said gas sensor element such that a leading end portion of said gas sensor element protrudes from its own leading end; and a protector fixed on said metal shell and covering said leading end portion of said gas sensor element, wherein said protector includes: a cylindrical outer cover portion fixed on said metal shell and having gas introducing apertures; and a cylindrical inner cover portion arranged on an inner side of said outer cover portion and having elastic portions being capable of being elastically deformed by a pushing force acting in an axial direction, and said inner cover portion is so clamped between said metal shell and said outer cover portion that said elastic portions are elastically deformed by said axial pushing force.

Abstract: An improved structure of a gas sensor is provided which is designed to provide a joint between a gas sensor element protective cover and a sensor housing which is insensitive to heat. The housing has formed on a side wall thereof a thread used to installation of the gas sensor, for example, in an exhaust pipe of automotive engines. The joint is located closer to a base end of the sensor housing than a top end of the thread. Specifically, when the gas sensor is installed in the exhaust pipe of the engine, the joint is located farther away from a heat source (i.e., exhaust gasses of the engine) than the top end of the thread, thereby avoiding loosening of the joint or dislodgement of the cover from the housing.

Abstract: A sensor element including an insulative base (11), a heating resistor (12), an oxygen pump cell (13), an oxygen detection cell (14), and a diffusion-chamber-forming member (161) having a rate-controlling introduction portion (163) and defining a diffusion chamber (16) in cooperation with electrodes (1321, 1421), wherein these components have been subjected to simultaneous firing (i.e., cofiring) to form a unitary sensor element. A partition wall (162), which extends from the diffusion-chamber-forming member and is made of alumina, is joined to a surface of a solid electrolyte (131) between two electrodes (1321, 1322) of an Ip cell. Preferably, a region within 20 ?m from the plane of junction joining the partition wall (162) to the solid electrolyte (131) contains no portion whose amount of non-alumina substances exceeds by 2% by mass (by weight) or more the amount of non-alumina substances of the diffusion-chamber-forming member (161).

Abstract: An insulator, airtightly supported via an annular metallic packing on a cylindrical housing, has a small-diameter portion and a large-diameter portion. A tapered surface extends in a radially outer direction from a small-diameter cylindrical surface to a large-diameter cylindrical surface. A receiving surface, formed on an inside wall of the housing, supports the tapered surface via the metallic packing. The tapered surface is brought into line contact with the metallic packing at its outer or inner circumferential portion.

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 gas sensor is provided, for example, a sensor for determining the concentration or the temperature of a gas component. The gas sensor has a housing, in which a sensor element having at least one contact surface is arranged. The contact surface is conductively connected to a conductor element. The sensor element having the contact surface and the conductor element is arranged between two contact supports situated opposite one another. A spring element contacting the contact supports presses the conductor element onto the contact surface. Each of the contact supports, on sides facing one another, has at least one recess and at least one protuberance, the protuberance of one contact support engaging in the recess of the other contact support, and vice versa.

Abstract: A gas sensor is disclosed which attains high response speed, low power consumption, superior water splash resistance and a little setting direction dependency and setting angle dependency. In this gas sensor, a measured gas room is provided inside an inner cover, and gas passage holes for leading a measured gas in are provided on side surfaces of the inner cover and an outer cover. The gas passage holes provided on the outer cover are positioned much closer to a top end side than the gas passage hole provided closest to the top end side in the inner cover. Partitions disposed extendedly in an axial direction of the gas sensor are provided between the outer cover and the inner cover.

Abstract: An improved structure of a protective cover assembly of a gas sensor is provided. The protective cover assembly is of a double-walled structure made up of an inner and an outer cylindrical cover with gas holes. A sensing element is disposed within the inner cover. At least one of the gas holes of the outer cover partially faces a side wall of the inner cover. A top end surface of the inner cover lies within a range defined between opposed portions of a perimeter of the at least one of the gas holes of the outer cover closest to a top and a base end of the cover assembly, respectively. This structure works to avoid breakage of the sensing element arising from wetting with water and to improve a response rate of the gas sensor.

Abstract: A sensor having a conductive protective sheath, an internal sensor element, and a conductive end cap. The conductive end cap is connected to the distal end of the conductive protective sheath and is in contact with the internal sensor element. The conductive protective sheath has a plurality of apertures symmetrically arranged to prevent fluid flow in a straight direction of a sample fluid through the conductive protective sheath. A sensor having a conductive protective sheath, an internal sensor element, and a conductive end cap. The conductive end cap is connected to the distal end of the conductive protective sheath. The conductive end cap one or more contact areas from the group including a side contact area, an upper contact area, and an internal indentation contact area. The internal sensor is in contact with at least one of the contact areas of the conductive end cap.

Abstract: A rapid response structure of a gas sensor which includes a protective cover assembly defining therein a gas chamber to which a gas to be measured is admitted. The gas assembly consists of an outer and an inner cover. The inner cover is disposed within the outer cover with a clearance which defines a gas path extending from gas inlet holes formed in the outer cover to the gas chamber through gas inlet holes formed in the inner cover. The outer and inner covers are so designed geometrically as to minimize the interference of a return gas flow produced within the clearance with the flow of the gas into the gas chamber, thereby facilitating the entrance of the gas into the gas chamber.

Abstract: A gas sensor (1a) having a laminate including an alumina substrate (11) having a heating resister (115) embedded in the alumina substrate (11); a first oxygen-ion conductive solid electrolyte layer (131) containing zirconia and alumina and partly constituting an oxygen-detecting cell (13) and the first solid electrolyte layer (131) being laminated with said alumina substrate (11); a second oxygen-ion conductive solid electrolyte layer (121) containing zirconia and alumina and partly constituting an oxygen-pumping cell (12); an ion-leakage preventing ceramic spacer (143) for preventing oxygen-ions from leaking from the second oxygen-ion conductive solid electrolyte layer (121) to the first oxygen-ion conductive solid electrolyte layer (131), the spacer (143) being laminated between the first and second oxygen-ion conductive solid electrolyte layers (131, 121); and a gas-diffusion space (141) formed between an electrode (133) of the oxygen-detecting cell (13) and an electrodes (126) of the oxygen-pumping cell (

Abstract: A gas sensor is provided which comprises a sensor element for detecting a component of a gas and a cup-shaped protector for covering a detecting section of the sensor element. The protector is dual-walled and have cup-shaped inner and outer protector members. The inner and outer protector members are constructed and arranged so that g1>g2 where g1 is the distance between an inner surface of a circumferential wall of the outer protector member and an outer surface of a circumferential wall of the inner protector member and g2 is the distance between an inner surface of a bottom wall of the outer protector member and an outer surface of a bottom wall of the inner protector member. The outer protector member has at the circumferential wall thereof a plurality of first gas holes. The inner protector member has at the circumferential wall thereof a plurality of second gas holes.

Abstract: An electrochemical sensor is provided for measuring the concentration of nitrogen oxides in a gas to be measured, in particular in the exhaust gas of internal combustion engines in motor vehicles, having a first pump cell which includes a solid electrolyte and a pair of electrodes situated thereon which are connected to a first pump voltage, and having a second pump cell situated downstream in the gas flow which includes a solid electrolyte and a pair of electrodes situated thereon which are connected to a second pump voltage. To achieve an easily manufactured, more economical design of the sensor, for the electrodes in a first pump cell, the first electrode is exposed to the exhaust gas and the second electrode is exposed to a reference gas, and for the electrodes in a second pump cell, the first electrode is exposed to the gas volume leaving the first pump cell and the second electrode is also exposed to the reference gas.

Abstract: A sensor element (10) for determining a gas component, in particular for determining the oxygen concentration in exhaust gases of internal combustion engines, is described; a measurement gas space (41) is introduced into the sensor element (10), and at least one electrode (31, 32) is provided in the measurement gas space, which is connected to the gas outside the sensor element (10) via a gas inlet opening (43). A diffusion barrier (44) is provided between the gas inlet opening (43) and the electrode (31, 32). At least one spacer element (50, 51) is provided in at least some areas of the measurement gas space (41) and has a higher pore content than the diffusion barrier (44) or it allows access of the measurement gas to at least the areas of the electrode (31, 32) not covered by the spacer element (50, 51).

Abstract: A measured gas side electrode is provided on one surface of a solid electrolytic substrate so as to be exposed to a measured gas. A reference gas side electrode is provided on an opposite surface of the solid electrolytic substrate so as to be exposed to a reference gas stored in a reference gas chamber. A water-vapor absorbing member is provided in the reference gas chamber.

Abstract: An electrochemical sensor element for determining the oxygen concentration in exhaust gases of internal combustion engines is described. The sensor element has a pump cell, which has a pump electrode situated on a surface of the sensor element facing the gas mixture, and a measuring gas electrode situated in a measuring gas area, the gas mixture entering the measuring gas area through a diffusion resistor. In addition, the sensor element has a reference electrode situated in a reference gas area. Another diffusion resistor is provided between the measuring gas area and the reference gas area.

Abstract: A gas sensor is provided which comprises a sensor element for detecting a component of a gas and a cup-shaped protector for covering a detecting section of the sensor element. The protector is dual-walled and have cup-shaped inner and outer protector members. The inner and outer protector members are constructed and arranged so that g1>g2 where g1 is the distance between an inner surface of a circumferential wall of the outer protector member and an outer surface of a circumferential wall of the inner protector member and g2 is the distance between an inner surface of a bottom wall of the outer protector member and an outer surface of a bottom wall of the inner protector member. The outer protector member has at the circumferential wall thereof a plurality of first gas holes. The inner protector member has at the circumferential wall thereof a plurality of second gas holes.

Abstract: A gas sensor comprises a first electrode and a second electrode; and an electrolyte disposed between the first electrode and the second electrode. The electrolyte is shaped into a cylinder having an axial open end portion, an axial middle portion, and an axial closed end portion. The axial closed end portion has a uniform wall thickness equal to or less than about 1.5 millimeters. A radial transition in an interior region of the electrolyte between the middle and the closed end portions forms a shoulder. Processes for sensing exhaust gas generally includes disposing the gas sensor in an exhaust stream, contacting the closed end portion of the sensor with exhaust gas, and creating an electromotive force. The sensor activates quickly due to the close proximity to a rod heater and the low thermal mass resulting from the small inner diameter and thin wall section of the closed end portion.

Abstract: A rapid response structure of a gas sensor which includes a protective cover assembly defining therein a gas chamber to which a gas to be measured is admitted. The gas assembly consists of an outer and an inner cover. The inner cover is disposed within the outer cover with a clearance which defines a gas path extending from gas inlet holes formed in the outer cover to the gas chamber through gas inlet holes formed in the inner cover. The outer and inner covers are so designed geometrically as to minimize the interference of a return gas flow produced within the clearance with the flow of the gas into the gas chamber, thereby facilitating the entrance of the gas into the gas chamber.

Abstract: An oxygen sensor is disposed downstream from a catalyst for purifying exhaust gas from an internal combustion engine and which can suppress an influence of unburnt hydrocarbon on an output voltage. After forming a platinum thin film on the outer periphery of a zirconia ceramic body, only a detection electrode of the ceramic body is dipped in a silver nitrate aqueous solution of 0.1 mol/l, and the silver nitrate is pyrolyzed through a heat treatment. Subsequently, a platinum reference electrode is formed on the inner periphery of the ceramic body. To protect the silver-doped detection electrode, a protective layer is formed on the surface of the detection electrode. By the exposure to combustion gas and through aging, a detection element is formed, and set into a metal case together with a cylindrical heater, to complete an oxygen sensor to be disposed downstream from a CNG engine catalyst.

Abstract: An improved structure of a mechanical seal for keeping a gas chamber and a reference gas chamber airtight in a sensor body. A sensor element is disposed within an insulator. A gap between the sensor element and the insulator is sealed hermetically by a glass sealing member. The glass sealing member has a coefficient of thermal expansion whose differences between itself and the sensor element and the insulator is within a range of ±3×10−6/° C. This provides a mechanical seal required to keep the reference gas chamber and the gas chamber in the gas sensor airtight in an environment such as an automotive exhaust system subjected to a great temperature change.

Abstract: A sensor structure having a metallic terminal member. The metallic terminal member 23 includes press portions 23d and 23e, which press the heating member 3 in a direction intersecting the center axis of a hollow portion 2a of an oxygen detection element 2. Holding means for holding the heating member 3 is formed separately from the metallic terminal member 23. Thus, without use of special heating-member holder means, the metallic terminal member 23 can bring at least a portion of the heating member 3 into contact with the inner wall surface of the hollow portion 2a of the oxygen detection element 2.

Abstract: A sensor and a method for making a sensor is disclosed. The method for making the sensor comprises: mixing a first metal oxide stabilized alumina with alpha alumina in a liquid to create a base slurry, mixing into said base slurry a second metal oxide stabilized alumina and a fugitive material to create a composition; applying said composition to at least a portion of a sensing element comprising two electrodes with an electrolyte disposed therebetween; and calcining said sensing element.

Abstract: A sensor element is proposed, particularly a lambda probe for analyzing exhaust gases in internal combustion engines, having a protective device which, at least region-wise, surrounds or covers a sensitive component of the sensor element exposed to a gas. Also provided is that the protective device has an arrangement or is joined to such an arrangement by which the admission of gas to the sensitive component is able to be regulated.

Abstract: One embodiment of a particulate sensor system; comprises a first sensing electrode and a second sensing electrode in thermal and electrical communication with a heater wherein the first sensing electrode and the second sensing electrode are disposed on the same side of an electrode substrate. One embodiment of a method for operating a particulate sensor system comprises introducing a gas stream to a sensor; monitoring the resistance between the first sensing electrode and the second sensing electrode, and increasing the temperature of the sensor when the resistance is greater than or equal to a first selected level. One embodiment of a method for operating a filter system comprises exposing a sensor to a pre-selected number of self-regeneration cycles, and increasing the temperature of the filter system.

Abstract: A second protective layer is a ceramic porous protective layer comprising coarse particles and fine particles structurally arranged in such a manner that interparticle cavities formed between the coarse particles are filled with the fine particles. At least either of the coarse particles and the fine particles contain at least one selected from the group consisting of &ggr;-Al2O3, &thgr;-Al2O3, &dgr;-Al2O3 and solid solution having the same crystal structure as those of &ggr;-Al2O3, &thgr;-Al2O3, &dgr;-Al2O3.

Abstract: A sensor element including an insulative base (11), a heating resistor (12), an oxygen pump cell (13), an oxygen detection cell (14), and a diffusion-chamber-forming member (161) having a rate-controlling introduction portion (163) and defining a diffusion chamber (16) in cooperation with electrodes (1321, 1421), wherein these components have been subjected to simultaneous firing (i.e., cofiring) to form a unitary sensor element. A partition wall (162), which extends from the diffusion-chamber-forming member and is made of alumina, is joined to a surface of a solid electrolyte (131) between two electrodes (1321, 1322) of an Ip cell. Preferably, a region within 20 &mgr;m from the plane of junction joining the partition wall (162) to the solid electrolyte (131) contains no portion whose amount of non-alumina substances exceeds by 2% by mass (by weight) or more the amount of non-alumina substances of the diffusion-chamber-forming member (161).

Abstract: An improved structure of a mechanical seal for keeping a gas chamber and a reference gas chamber airtight in a sensor body. A packing seal is disposed between a shoulder formed on an inner wall of a housing of the sensor body and a tapered surface of an insulation porcelain installed in the housing to define the gas chamber and the reference gas chamber hermetically. The packing ring is formed by a metal plate which has a thickness of 0.1 mm or more and a Vickers hardness of 200 or less and which is made of at least one of a nickel, a nickel alloy, a titanium, and a stainless steel.

Abstract: An exhaust gas sensor is provided and formed by attaching the sensor's upper shield and shell. The attachment is attained by bending a protruding segment or lip over a terminal end portion of the lower shield. This produces a single sealing surface and eliminates the requirement of a conventional crimp which places high compressive forces on the sensing element.

Abstract: Disclosed herein is a gas sensor having a small amount of lead oxide incorporated into an inner electrode and an outer electrode, and a method for depositing the lead oxide. The lead oxide is applied in an amount sufficient to effectuate consistent performance during sensor break-in. Lead oxide is transferred to the electrodes of the sensor element during the fabrication process by exposing the sensor element to glass having a known lead content during a heating step. Lead oxide from the glass is vaporized and deposited on the electrodes in the form of lead oxide. The deposited lead oxide is incorporated into the electrodes of the sensor element. The lead oxide reduces performance irregularities thereby improving performance during the initial use of the gas sensor.

Abstract: The protective shield arrangement for an exhaust sensor and method of making and using the same is achieved by providing a protective shield for an exhaust gas sensor that comprises a porous mesh material formed as a cap for placement over an end portion of a sensing element. This is formed by a method that comprises providing a unitary piece of the mesh material, and folding the mesh material to form the cap. Thereby, gas passes through the tortuous pathway created by the mesh material to be sensed by the sensor.

Abstract: A sensor for determining gas components and concentrations in a gas mixture that is particularly suitable for analyzing HC, NOx and CO in exhaust gases of internal combustion engines in the sensor, an outer electrode, that is separated from an MOx electrode by an electrolyte layer, is applied on a substrate. In this context, the outer electrode and the MOx electrode are in communication with the gas mixture to be analyzed. In addition, the outer electrode contains a region that is in contact with a gas-permeable tunnel layer which in turn contains a region that is directly exposed to the gas mixture to be analyzed, so that the gas to be analyzed can be supplied to the outer electrode via the gas-permeable tunnel layer.

Abstract: A heater is inserted into an inside chamber of a sensor element until a tip end of the heater is surely brought into contact with a bottom surface of the inside chamber. Next, a metallic holder is attached on an outside surface of the heater. Then, the metallic holder is slid along the outside surface of the heater toward the bottom surface of the sensor element to engage the metallic holder with an edge of the sensor element.

Abstract: Disclosed is a method for fabricating biosensors, using hydrophilic polyurethane. Bio-active reagents, including enzymes, antibodies, antigens, cells and receptors, are mixed with hydrophilic polyurethane and the mixture is directly coated over a signal transducer to form a sensing film which serves as a signal detector. The method using hydrophilic polyurethane allows the simplification of the fabrication of biosensors without conducting complicated chemical reactions and washing steps, such as crosslinking. The bio-active reagent entrapped within the hydrophilic polyurethane film can retains its high activity for an extended period of time and the intrinsic potentiometric response of the underlying ion-selective polymeric membrane is not affected by the bio-active reagent immobilized polyurethane film coated on its sensing surface. Therefore, the biosensors are superior in specificity, selectivity, and stability.