公开(公告)号：US20150276659A1

公开(公告)日：2015-10-01

申请号：US14672735

申请日：2015-03-30

Applicant: NGK Insulators, Ltd.

Inventor： Takayuki SEKIYA ,  Naoya SAITO ,  Shota KAGEYAMA

IPC: G01N27/407 ,  G01N27/409

CPC classification number: G01N27/4071 ,  G01N27/409 ,  G01N27/417

Abstract: In a sensor element 101, a reference gas regulation pump cell 90 pumps in oxygen to the periphery of a reference electrode 42 in which a reference gas is introduced, by the flow of a control current Ip3 between the reference electrode 42 and an outer pump electrode 23 located in a region exposed to a measurement-object gas. An average current density of the reference electrode 42 under the flow of this control current Ip3 is higher than 0 μA/mm2 and lower than 400 μA/mm2. The average current density is preferably not higher than 170 μA/mm2. An average value of the control current Ip3 is preferably higher than 1 μA. The outer pump electrode 23 as a measurement-object gas side electrode of the reference gas regulation pump cell 90 may be provided on an outer surface of a layered body (or more specifically, on a second solid electrolyte layer 6).

Abstract translation: 在传感器元件101中，参考气体调节泵电池90通过参考电极42和外部泵电极之间的控制电流Ip3的流动将氧气泵送到参考电极42的周围，其中引入参考气体 23位于暴露于测量对象气体的区域中。 在该控制电流Ip3的流动下，参考电极42的平均电流密度高于0μA/ mm 2且低于400μA/ mm 2。 平均电流密度优选不高于170μA/ mm 2。 控制电流Ip3的平均值优选高于1μA。 作为基准气体调节泵电池90的测量对象气体侧电极的外部泵电极23可以设置在层叠体的外表面（或更具体地，在第二固体电解质层6上）。

公开(公告)号：US20240377350A1

公开(公告)日：2024-11-14

申请号：US18783522

申请日：2024-07-25

Applicant: NGK INSULATORS, LTD.

Inventor： Sotaro INAGAKI ,  Shiho IWAI ,  Ryota TOMIOKA ,  Takayuki SEKIYA

IPC: G01N27/41 ,  G01N27/407

Abstract: A sensor element includes: a base part in an elongated plate shape; a measurement-object gas flow part formed from one end part in a longitudinal direction of the base part; an inner main pump electrode disposed on an inner surface of the measurement-object gas flow part; an outer pump electrode disposed in correspondence with the inner main pump electrode; and a measurement electrode disposed at a position farther from the one end part than the inner main pump electrode on the inner surface of the measurement-object gas flow part. The outer pump electrode is disposed at a position farther from the one end part in the longitudinal direction of the base part than one electrode end of the inner main pump electrode closer to the one end part in the longitudinal direction of the base part, with respect to the longitudinal direction of the base part.

公开(公告)号：US20240011942A1

公开(公告)日：2024-01-11

申请号：US18472553

申请日：2023-09-22

Applicant: NGK INSULATORS, LTD.

Inventor： Takayuki SEKIYA ,  Yusuke WATANABE ,  Kodai ICHIKAWA

IPC: G01N27/419 ,  G01N33/00

CPC classification number: G01N27/419 ,  G01N33/0037

Abstract: A sensor element for detecting a specific gas concentration in a measurement-object gas, the sensor element includes: an element body internally provided with a measurement-object gas flow portion that introduces a measurement-object gas and causes the measurement-object gas to flow therethrough; a reference-gas introduction portion disposed inside the element body, the reference-gas introduction portion being configured to introduce a reference gas; a reference-gas adjustment pump cell having a pump reference electrode disposed inside the element body, the reference-gas adjustment pump cell being configured to pump oxygen into a periphery of the pump reference electrode; and a sensor cell having a voltage reference electrode disposed inside the element body, and a measurement-object gas-side electrode disposed inside or outside the element body, the sensor cell being configured to generate a voltage based on an oxygen concentration in a periphery of the measurement-object gas-side electrode.

公开(公告)号：US20220236212A1

公开(公告)日：2022-07-28

申请号：US17577426

申请日：2022-01-18

Applicant: NGK Insulators, Ltd.

Inventor： Takayuki SEKIYA ,  Yusuke WATANABE ,  Shiho IWAI

IPC: G01N27/409 ,  G01N33/00 ,  G01N27/41 ,  G01N27/417 ,  G01N27/407

Abstract: A sensor element includes: a base part containing an oxygen-ion conductive solid electrolyte as a constituent material; at least one internal space into which a measurement gas is introduced; and at least one pump cell including an internal electrode disposed to face the internal space, an out-of-space pump electrode disposed at a location other than the internal space, and a portion of the base part located between these electrodes, the internal electrode includes a noble metal, the solid electrolyte, and a pore, and, in the internal electrode, a degree of variation of a boundary of a first region formed of the base part or the solid electrolyte contiguous with the base part and a second region occupied by the noble metal and the pore in a thickness direction of the element is 0.5 μm or more and 6.5 μm or less.

公开(公告)号：US20220011258A1

公开(公告)日：2022-01-13

申请号：US17487027

申请日：2021-09-28

Applicant: NGK INSULATORS, LTD.

Inventor： Takayuki SEKIYA ,  Yusuke WATANABE

IPC: G01N27/406 ,  G01N27/407 ,  G01N27/41

Abstract: Provided are a gas sensor and a method for controlling the gas sensor, wherein the gas sensor comprises: a heater unit which performs a temperature adjustment of heating and keeping a sensor element warm; a pump drive control unit which controls pump driving for at least a gas-to-be measured flow unit; a measurement pump cell which detects a concentration of a specific gas in the gas to be measured, on the basis of an electromotive force generated between a reference electrode and a measurement electrode; a heater control unit which controls the heater unit; and a pump stop unit which stops the pump driving by the pump drive control unit after the heater control unit stops energizing the heater unit.

公开(公告)号：US20210302400A1

公开(公告)日：2021-09-30

申请号：US17208060

申请日：2021-03-22

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Takayuki SEKIYA

IPC: G01N33/00 ,  G01N27/419 ,  G01N27/409 ,  G01N27/407 ,  G01N27/41

Abstract: A limiting-current type gas sensor including a sensor element including a base part made of an oxygen-ion conductive solid electrolyte and measuring concentration of NOx in a measurement gas includes: a pump cell including a first electrode disposed to be capable of being in contact with a gas introduced into the element and a second electrode disposed so that a part made of the solid electrolyte is located between the first electrode and the second electrode; and a pumping diagnostic part to determine whether an inter-electrode electric field produced in the part made of the solid electrolyte through application of a predetermined pump voltage between the electrodes exceeds a first threshold, and, when the inter-electrode electric field exceeds the first threshold, the predetermined pump voltage is reduced so that the inter-electrode electric field falls below the first threshold.

公开(公告)号：US20210302354A1

公开(公告)日：2021-09-30

申请号：US17192070

申请日：2021-03-04

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Takayuki SEKIYA

IPC: G01N27/409 ,  G01N27/407

Abstract: A sensor element for detecting a specific gas concentration in a measurement-object gas includes: an element body including an oxygen-ion-conductive solid electrolyte layer, and having inside a measurement-object gas flow portion that introduces and flows a measurement-object gas and a reference gas chamber used to store a reference gas that is a reference for detecting a specific gas concentration; a reference electrode disposed in the reference gas chamber; and an electrically conductive portion which includes a reference electrode terminal and a reference electrode lead portion that provides electrical continuity between the reference electrode terminal and the reference electrode. The reference gas chamber is provided inside the sensor element in an isolated form, and at least part of the electrically conductive portion is densely formed so as to block movement of oxygen between the reference gas chamber and the outside of the sensor element via the electrically conductive portion.

公开(公告)号：US20200064302A1

公开(公告)日：2020-02-27

申请号：US16669558

申请日：2019-10-31

Applicant: NGK INSULATORS, LTD.

Inventor： Takayuki SEKIYA ,  Shota KAGEYAMA ,  Yusuke WATANABE

IPC: G01N27/407 ,  G01N27/417

Abstract: A gas sensor element in which oxidation of electrodes and a heater occurring with continued use is suppressed is provided. The gas sensor element includes a plurality of solid electrolyte layers stacked one over another, and includes an electrochemical cell including a pair of electrodes and a portion of the plurality of solid electrolyte layers existing between the pair of electrodes; a heater part capable of heating the gas sensor element; and a gettering layer located between the plurality of solid electrolyte layers and between the plurality of solid electrolyte layers and each of the pair of electrodes, and gettering impurities in a metal component of the electrodes and the heater part during driving of the gas sensor element.

公开(公告)号：US20180074009A1

公开(公告)日：2018-03-15

申请号：US15697952

申请日：2017-09-07

Applicant: NGK INSULATORS, LTD.

Inventor： Taku OKAMOTO ,  Nobuhiko MORI ,  Takayuki SEKIYA

IPC: G01N27/407 ,  G01N33/00

Abstract: A sensor element includes a NOx sensor part, a NH3 gas sensor part, and a single common electrode shared by the both parts. The former has a pump cell including a measurement electrode facing an internal space, a pump electrode formed on a surface of the element, and a solid electrolyte therebetween. The latter includes a sensing electrode formed on a surface of the element and having catalytic activity inactivated for a NH3 gas. The common electrode is located to be in contact with a reference gas. The NOx concentration is determined based on a potential difference occurring between the sensing electrode and the common electrode, and a current flowing through the pump cell in a state of controlling a voltage applied across the electrodes to maintain a potential difference between the measurement electrode and the common electrode constant.

公开(公告)号：US20230194462A1

公开(公告)日：2023-06-22

申请号：US18079035

申请日：2022-12-12

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Daichi ICHIKAWA ,  Kodai ICHIKAWA ,  Takayuki SEKIYA

IPC: G01N27/409 ,  G01N33/00

CPC classification number: G01N27/409 ,  G01N33/0027

Abstract: A gas sensor includes a sensor element and a control unit for controlling the sensor element. The sensor element includes: an adjustment pump cell for adjusting an oxygen concentration in a measurement-object gas to a desired concentration; a current measurement pump cell for detecting a target gas to be measured in the measurement-object gas as a current value, the current measurement pump cell including: an inner measurement electrode and an outer measurement electrode; a reference electrode; and an electromotive force detection sensor cell for detecting an electromotive force value between the inner measurement electrode and the reference electrode. The control unit includes a switching unit for switching whether a current flows through the current measurement pump cell or not.