Abstract: A gas sensor is equipped with a housing, an insulator retained by an inner periphery of the housing, a sensing device having a front end portion protruding from a front end surface of the insulator, and a protective cover which covers a front end portion of the sensing device. A pump electrode and a sensor electrode are disposed in a front end portion of the solid electrolyte body. The pump electrode is exposed to a measurement gas and regulates the concentration of oxygen in the measurement gas. The sensor electrode is exposed to the measurement gas and measures the concentration of a given gas component in the measurement gas after being regulated in concentration of oxygen by the pump electrode. A base end portion of the sensor electrode in a lengthwise direction is located closer to a base end side of the gas sensor than a front end surface of the housing is.

Abstract: A gas concentration detection apparatus is provided with a measuring gas chamber, a solid electrolyte body, a pump cell, a sensor cell, a pump cell controller and a sensor cell detection section. The pump cell controller applies an elimination voltage to the pump cell at a start-up point, before a gas concentration is detected. The water in the measuring gas chamber is decomposed and hydrogen is generated by application of the elimination voltage. Oxygen occluded in a sensor electrode of the sensor cell is removed by the hydrogen.

Abstract: A gas sensor includes a solid electrolyte, a gas chamber, a reference gas chamber, a pump cell, a monitor cell, and a sensor cell. The gas chamber has a spatial width W0 constant in a width direction W orthogonal to the direction of flow of a gas in a position where the pump electrode, the monitor electrode, and the sensor electrode are provided on the solid electrolyte. An amount of shift ?X1 of a central position O2 of a gap S in the width direction W between the monitor electrode and the sensor electrode from a central position O1 in the width direction of the pump electrode has relationship of ?X1?¼ W1 where the pump electrode has a width W1. In addition, positions ?Y1 of a of a side surface of the monitor electrode and of a side surface of the sensor electrode from the central position O1 in the width direction W of the pump electrode have relationship of ?Y1?½ W1.

Abstract: A gas sensor is equipped with a solid electrolyte body, a pump electrode, a sensor electrode, and a heater. In the gas sensor, a region of the whole of a front end portion of a heater base in which a heating element is disposed is broken down into three regions: an intermediate region defined between a front end and a base end of the sensor electrode, a front end region located closer to a front end side than the intermediate region is, and a base end region located closer to a base end side than the intermediate region is. A resistance value per unit area of a heating element lying in the base end region and a resistance value per unit area of the heating element lying in the front end region is selected to be higher than that of the heating element lying in the intermediate region, thereby keeping the temperature of a region around the sensor electrode at a desired level even when the temperature of gas changes.

Abstract: A gas sensor device is equipped with the sensor cell, the pump cell, the inner void space, and the gas inlet. The sensor cell is created by a portion of the solid electrolyte body and a pair of sensor electrodes disposed on the solid electrolyte body. The pump cell is created by a portion of the solid electrolyte body and a pair of pump electrodes disposed on the solid electrolyte body. The inner void space faces the sensor electrode and the pump electrode. If a dimension of said gas inlet in a direction in which the measurement gas flows in the gas inlet is defined as L1, a sectional area of the gas inlet taken perpendicular to the direction of flow of the measurement gas in the gas inlet is defined as S1, a distance between the gas inlet and the sensor cell is defined as L2, and a sectional area of the inner void space taken perpendicular to a direction in which the pump cell and the sensor cell are aligned with each other is defined as S2, a relation of 1000?(L1/S1)×(L2/S2)?5000 is met.

Abstract: A sensor structural body, which is formed by stacking a sensor element and a heater, has a sensor protruding portion that protrudes distalward from a holder. The sensor element includes a solid electrolyte body, a measured-gas space, a reference-gas space, a pump cell, a monitor cell and a sensor cell. A heat-generating portion of the heater is entirely arranged in the sensor protruding portion. The length L (in mm) of a formation region of the heat-generating portion and the length H (in mm) of the sensor protruding portion in a longitudinal direction, in which the sensor protruding portion protrudes from the holder, are set to be in a range that is enclosed by first to fourth reference lines X1, X2, X3 and X4 on a two-dimensional coordinate plane whose horizontal and vertical axes respectively indicate the lengths L and H. The first to the fourth reference lines X1-X4 respectively represent the relationships of H=L, H=20, H=?4.24L+42.71 and H=?4.24L+68.6.

Abstract: A gas concentration measuring apparatus is provided which works to calculate the concentration of a given gas component with enhanced accuracy. The gas concentration measuring apparatus 1 includes, a gas sensor 10 and a calculating portion 11. The gas sensor 10 is equipped with a pump cell 3, a monitor cell 4, and a sensor cell 5. The calculating portion 11 subtracts a monitor cell current Im that is a current flowing through the monitor cell 4 from a sensor cell current Is that is a current flowing through the sensor cell 5 to calculate the concentration of the given gas component in gas g. When calculating the concentration of the given gas component, the calculating portion 11 performs a correction operation to bring a value of the monitor cell current Im close to a value of an oxygen dependent current Iso that is a component of the sensor cell current Is which arises from the concentration of oxygen.

Abstract: A gas concentration measuring apparatus is provided which works to calculate the concentration of a given gas component with enhanced accuracy. The gas concentration measuring apparatus 1 includes, a gas sensor 10 and a calculating portion 11. The gas sensor 10 is equipped with a pump cell 3, a monitor cell 4, and a sensor cell 5. The calculating portion 11 subtracts a monitor cell current Im that is a current flowing through the monitor cell 4 from a sensor cell current Is that is a current flowing through the sensor cell 5 to calculate the concentration of the given gas component in gas g. When calculating the concentration of the given gas component, the calculating portion 11 performs a correction operation to bring a value of the monitor cell current Im close to a value of an oxygen dependent current Iso that is a component of the sensor cell current Is which arises from the concentration of oxygen.

Abstract: A gas concentration measuring apparatus is provided which works to calculate the concentration of a given gas component with enhanced accuracy. The gas concentration measuring apparatus 1 includes, a gas sensor 10 and a calculating portion 11. The gas sensor 10 is equipped with a pump cell 3, a monitor cell 4, and a sensor cell 5. The calculating portion 11 subtracts a monitor cell current Im that is a current flowing through the monitor cell 4 from a sensor cell current Is that is a current flowing through the sensor cell 5 to calculate the concentration of the given gas component in gas g. When calculating the concentration of the given gas component, the calculating portion 11 performs a correction operation to bring a value of the monitor cell current Im close to a value of an oxygen dependent current Iso that is a component of the sensor cell current Is which arises from the concentration of oxygen.

Abstract: A gas sensor is equipped with a solid electrolyte body, a pump electrode, a sensor electrode, and a heater. In the gas sensor, a region of the whole of a front end portion of a heater base in which a heating element is disposed is broken down into three regions: an intermediate region defined between a front end and a base end of the sensor electrode, a front end region located closer to a front end side than the intermediate region is, and a base end region located closer to a base end side than the intermediate region is. A resistance value per unit area of a heating element lying in the base end region and a resistance value per unit area of the heating element lying in the front end region is selected to be higher than that of the heating element lying in the intermediate region, thereby keeping the temperature of a region around the sensor electrode at a desired level even when the temperature of gas changes.

Abstract: A gas sensor is equipped with a housing, an insulator retained by an inner periphery of the housing, a sensing device having a front end portion protruding from a front end surface of the insulator, and a protective cover which covers a front end portion of the sensing device. A pump electrode and a sensor electrode are disposed in a front end portion of the solid electrolyte body. The pump electrode is exposed to a measurement gas and regulates the concentration of oxygen in the measurement gas. The sensor electrode is exposed to the measurement gas and measures the concentration of a given gas component in the measurement gas after being regulated in concentration of oxygen by the pump electrode. A base end portion of the sensor electrode in a lengthwise direction is located closer to a base end side of the gas sensor than a front end surface of the housing is.

Abstract: A gas concentration detection apparatus is provided with a measuring gas chamber, a solid electrolyte body, a pump cell, a sensor cell, a pump cell controller and a sensor cell detection section. The pump cell controller applies an elimination voltage to the pump cell at a start-up point, before a gas concentration is detected. The water in the measuring gas chamber is decomposed and hydrogen is generated by application of the elimination voltage. Oxygen occluded in a sensor electrode of the sensor cell is removed by the hydrogen.

Abstract: A gas sensor device is equipped with the sensor cell, the pump cell, the inner void space, and the gas inlet. The sensor cell is created by a portion of the solid electrolyte body and a pair of sensor electrodes disposed on the solid electrolyte body. The pump cell is created by a portion of the solid electrolyte body and a pair of pump electrodes disposed on the solid electrolyte body. The inner void space faces the sensor electrode and the pump electrode. If a dimension of said gas inlet in a direction in which the measurement gas flows in the gas inlet is defined as L1, a sectional area of the gas inlet taken perpendicular to the direction of flow of the measurement gas in the gas inlet is defined as S1, a distance between the gas inlet and the sensor cell is defined as L2, and a sectional area of the inner void space taken perpendicular to a direction in which the pump cell and the sensor cell are aligned with each other is defined as S2, a relation of 1000?(L1/S1)×(L2/S2)?5000 is met.

Abstract: A sensor structural body, which is formed by stacking a sensor element and a heater, has a sensor protruding portion that protrudes distalward from a holder. The sensor element includes a solid electrolyte body, a measured-gas space, a reference-gas space, a pump cell, a monitor cell and a sensor cell. A heat-generating portion of the heater is entirely arranged in the sensor protruding portion. The length L (in mm) of a formation region of the heat-generating portion and the length H (in mm) of the sensor protruding portion in a longitudinal direction, in which the sensor protruding portion protrudes from the holder, are set to be in a range that is enclosed by first to fourth reference lines X1, X2, X3 and X4 on a two-dimensional coordinate plane whose horizontal and vertical axes respectively indicate the lengths L and H. The first to the fourth reference lines X1-X4 respectively represent the relationships of H=L, H=20, H=?4.24L+42.71 and H=?4.24L+68.6.

Abstract: A NOx concentration measurement system has a NOx sensor, a detection section, a NH3 concentration estimation section and a calculation section. The NOx sensor measures a sum concentration c4 of a concentration of NOx (a concentration c1 of combustion derived NOx) in exhaust gas g, and a concentration of NO (concentration c3 of derived NO which has been derived from NH3) oxidized from NH3. The calculation section calculates the concentration c3 of derived NO by using a concentration c2 of NH3 contained in outside exhaust gas which is present around the NOx sensor, not inside of the NOx sensor, and at least one of an air fuel ratio A/F, a concentration of O2 and a concentration of H2O. The concentration c1 of the is calculated based on the sum concentration c4 and the concentration c3 of derived NO.

Abstract: A gas sensor includes a solid electrolyte, a gas chamber, a reference gas chamber, a pump cell, a monitor cell, and a sensor cell. The gas chamber has a spatial width W0 constant in a width direction W orthogonal to the direction of flow of a gas in a position where the pump electrode, the monitor electrode, and the sensor electrode are provided on the solid electrolyte. An amount of shift ?X1 of a central position O2 of a gap S in the width direction W between the monitor electrode and the sensor electrode from a central position O1 in the width direction of the pump electrode has relationship of ?X1?¼ W1 where the pump electrode has a width W1. In addition, positions ?Y1 of a of a side surface of the monitor electrode and of a side surface of the sensor electrode from the central position O1 in the width direction W of the pump electrode have relationship of ?Y1?½ W1.

Abstract: The temperature sensor includes a thermo-sensitive element, first and second electrode wires electrically connected to the thermo-sensitive element, first and second signal wires partially overlapped with and connected to the first and second electrode wires, respectively. The first and second electrode wires are made of a first metal material consisting primarily of Pt. The first and second signal wires are made of a second metal material containing Al and having a linear thermal expansion coefficient larger than that of the first metal material. Each of an overlap portion of the first electrode wire and the first signal wire and an overlap portion of the second electrode wire and the second signal wire includes a junction part formed by melting and thereafter coagulating the first or second electrode wire and the first or second signal wire. The junction part includes an oxidation film containing Al formed on a surface thereof.

Abstract: A gas concentration measuring apparatus is provided which works to calculate the concentration of a given gas component with enhanced accuracy. The gas concentration measuring apparatus 1 includes, a gas sensor 10 and a calculating portion 11. The gas sensor 10 is equipped with a pump cell 3, a monitor cell 4, and a sensor cell 5. The calculating portion 11 subtracts a monitor cell current Im that is a current flowing through the monitor cell 4 from a sensor cell current Is that is a current flowing through the sensor cell 5 to calculate the concentration of the given gas component in gas g. When calculating the concentration of the given gas component, the calculating portion 11 performs a correction operation to bring a value of the monitor cell current Im close to a value of an oxygen dependent current Iso that is a component of the sensor cell current Is which arises from the concentration of oxygen.

Abstract: A temperature sensor has a temperature sensitive element for detecting a temperature, a sheath pin having core wires electrically connected to the temperature sensitive element, lead wires to output a detection signal of the temperature sensitive element to an outside device, connectors through which the core wires and the lead wires are connected, and a protection tube accommodating the core wires, the lead wires and the connectors. The protection tube has a supporting member made of an elastic member having inserting and supporting holes through which the connectors are inserted and supported. Each connector has a circular arc part and claw parts. The circular arc part is made along a profile of a front end part of each lead wire. The claw parts are formed at both the end parts of the circular arc part. Each claw part pushes an inner wall surface of the corresponding inserting and supporting hole.

Abstract: The temperature sensor includes a thermo-sensitive element, first and second electrode wires electrically connected to the thermo-sensitive element, first and second signal wires partially overlapped with and connected to the first and second electrode wires, respectively. The first and second electrode wires are made of a first metal material consisting primarily of Pt. The first and second signal wires are made of a second metal material containing Al and having a linear thermal expansion coefficient larger than that of the first metal material. Each of an overlap portion of the first electrode wire and the first signal wire and an overlap portion of the second electrode wire and the second signal wire includes a junction part formed by melting and thereafter coagulating the first or second electrode wire and the first or second signal wire. The junction part includes an oxidation film containing Al formed on a surface thereof.