公开(公告)号：US20230314367A1

公开(公告)日：2023-10-05

申请号：US18187108

申请日：2023-03-21

Applicant: NGK INSULATORS, LTD.

Inventor： Yuichiro KONDO ,  Taku OKAMOTO

IPC: G01N27/41 ,  G01M15/10 ,  G01N27/27

CPC classification number: G01N27/41 ,  G01M15/102 ,  G01N27/27

Abstract: A sensor element includes first to third chambers communicating sequentially from a gas inlet, voltages are intermittently applied across inner electrodes facing the respective chambers and a reference pump electrode to perform pumping of oxygen between a measurement gas and the reference pump electrode being in contact with a reference gas, thereby to reduce H2O and CO2 in the measurement gas into H2 and CO in the first chamber, to oxidize H2 into H2O in the second chamber, to oxidize CO into CO2 in the third chamber, and to identify a concentration of H2O and a concentration of CO2 based on a pumping-in current at the time when electromotive force between an inner electrode and the reference pump electrode during non-application of a voltage is maintained at a target value.

公开(公告)号：US20210054796A1

公开(公告)日：2021-02-25

申请号：US16986319

申请日：2020-08-06

Applicant: NGK INSULATORS, LTD.

Inventor： Taku OKAMOTO ,  Osamu NAKASONE

IPC: F02D41/14 ,  G01N27/407 ,  G01N27/41

Abstract: In a method of performing active control between a lean operation state and a rich operation state on a vehicle engine including a three way catalyst in an exhaust path, on a downstream side with respect to the three way catalyst in the exhaust path, a limited current type NOx sensor having NH3 interference and also capable of detecting a change in an oxygen concentration on the downstream side is disposed, and an operation state of the vehicle engine is switched between a lean operation state and a rich operation state at a timing when a detection of a change in an oxygen concentration in an exhaust air flowing out from the three way catalyst or a detection of NOx or NH3 is performed first by the NOx sensor.

公开(公告)号：US20190285571A1

公开(公告)日：2019-09-19

申请号：US16297977

申请日：2019-03-11

Applicant: NGK INSULATORS, LTD.

Inventor： Taku OKAMOTO ,  Akira SASAKI

IPC: G01N27/407

Abstract: A sensor element includes an element main body having an oxygen ion-conducting solid electrolyte body, a detection electrode which is disposed on an outer surface of the element main body and contains Pt and Au, a reference electrode which is disposed in the element main body, a connecting terminal for detection electrode which is disposed on the outside of the element main body, a lead portion for detection electrode which contains Pt, is disposed on the outside of the element main body, and electrically connects between the detection electrode and the connecting terminal for detection electrode, a lower insulating layer which is disposed between the lead portion for detection electrode and the element main body and insulates the two from each other, and an upper insulating layer which covers a surface of the lead portion for detection electrode and has a porosity of 10% or less.

公开(公告)号：US20190250123A1

公开(公告)日：2019-08-15

申请号：US16263043

申请日：2019-01-31

Applicant: NGK INSULATORS, LTD.

Inventor： Taku OKAMOTO

IPC: G01N27/407 ,  F01N3/20 ,  G01N33/00 ,  G01N27/30 ,  G01N27/406 ,  G01N27/409

CPC classification number: G01N27/4074 ,  F01N3/208 ,  F01N2560/021 ,  F01N2610/02 ,  G01N27/301 ,  G01N27/4067 ,  G01N27/4076 ,  G01N27/4077 ,  G01N27/409 ,  G01N33/0054

Abstract: A particular-gas concentration-measuring apparatus measures a particular gas concentration being the concentration of a particular gas in a measurement-object gas. The particular-gas concentration-measuring apparatus is included a particular-gas concentration derivation unit. The particular-gas concentration derivation unit causes an electromotive-force acquisition unit to acquire an electromotive force and derives a correction value compensating for the difference between a correction-value derivation electromotive force that is the electromotive force and the reference electromotive force at a correction-value derivation time. The correction-value derivation time is time during which a sensing electrode is exposed to a correction-value derivation gas, the correction-value derivation gas being the measurement-object gas that is under the condition where neither ammonia nor a combustible gas is assumed to be included. The particular-gas concentration derivation unit derives the particular gas concentration using a corrected electromotive force determined by correcting the electromotive force with the correction value.

公开(公告)号：US20180113103A1

公开(公告)日：2018-04-26

申请号：US15673701

申请日：2017-08-10

Applicant: NGK INSULATORS, LTD.

Inventor： Taku OKAMOTO ,  Yoshinobu NAKADA ,  Kosuke MONNA

IPC: G01N33/00 ,  G01N31/00

CPC classification number: G01N33/0054 ,  G01N27/4074 ,  G01N27/419 ,  G01N31/005 ,  G01N33/0031 ,  Y02A50/246

Abstract: A apparatus 70 for measuring ammonia concentration includes an electromotive force acquisition section 75 configured to acquire information about an electromotive force EMF of a mixed potential cell 55 while a detection electrode 51 is exposed to a target gas, an oxygen concentration acquisition section 76 configured to acquire information about oxygen concentration pO2 in the target gas, and a control section 72. The control section 72 derives ammonia concentration pNH3 in the target gas from the acquired information about the electromotive force EMF, the acquired information about the oxygen concentration pO2, and the relationship represented by formula (1): EMF=α loga(pNH3)−β logb(pO2)+B  (1) where α, β, and B each represent a constant, and a and b each represent any base (provided that a≠1, a>0, b≠1, and b>0).

公开(公告)号：US20180094564A1

公开(公告)日：2018-04-05

申请号：US15708380

申请日：2017-09-19

Applicant: NGK INSULATORS, LTD.

Inventor： Taku OKAMOTO ,  Nobuhiko MORI ,  Yuki NAKAYAMA ,  Noriko HIRATA

IPC: F01N11/00 ,  G01N27/406 ,  G01N27/407 ,  G01N27/41 ,  F01N13/00

CPC classification number: F01N11/002 ,  B01D53/944 ,  B01D53/9495 ,  F01N3/103 ,  F01N13/008 ,  F01N2370/02 ,  F01N2550/02 ,  F01N2560/023 ,  F01N2560/026 ,  F01N2560/20 ,  F01N2570/10 ,  F01N2570/12 ,  G01N27/4065 ,  G01N27/4067 ,  G01N27/4071 ,  G01N27/4075 ,  G01N27/41 ,  G01N27/419 ,  Y02T10/47

Abstract: In a gas sensor determining a NOx concentration in a measurement gas based on a pump current flowing between a NOx measurement electrode and an outer pump electrode, the outer pump electrode has catalytic activity inactivated for HC and CO, so that a sensor element further includes a HC sensor part having a mixed potential cell constituted by the outer pump electrode, a reference electrode, and a solid electrolyte between these electrodes, and a HC mode for determining a HC concentration in the measurement gas based on a potential difference between the outer pump electrode and the reference electrode when the sensor element is heated to a temperature which is 400° C. or higher and 650° C. or lower and a NOx mode for determining a NOx concentration in the measurement gas based on the pump current can selectively be performed based on the temperature of the sensor element.

公开(公告)号：US20170184538A1

公开(公告)日：2017-06-29

申请号：US15370069

申请日：2016-12-06

Applicant: NGK INSULATORS, LTD.

Inventor： Taku OKAMOTO ,  Takayuki SAKURAI ,  Noriko HIRATA ,  Yuki NAKAYAMA

IPC: G01N27/407 ,  G01N27/406 ,  G01N27/30

CPC classification number: G01N27/4074 ,  G01N27/301 ,  G01N27/4067 ,  G01N27/4075 ,  G01N27/4076 ,  G01N27/4077 ,  G01N33/0054 ,  Y02A50/246

Abstract: Provided is a gas sensor which is capable of preferably sensing an ammonia gas, and has excellent durability. A mixed-potential gas sensor includes a sensor element composed of an oxygen-ion conductive solid electrolyte, and a heater provided inside the element. The sensor element includes on a surface thereof a sensing electrode formed of a cermet including Pt, Au and an oxygen-ion conductive solid electrolyte, and also includes a reference electrode formed of a cermet of Pt and an oxygen-ion conductive solid electrolyte, and a porous electrode protective layer whose porosity is 5 to 40% covering at least the sensing electrode. The Au abundance ratio in a surface of noble metal particles forming the sensing electrode is 0.4 or more. The concentration of an ammonia gas is determined on the basis of a potential difference occurring between the sensing electrode and the reference electrode when the sensor element is disposed in a measurement gas and heated to 400° C. to 800° C.

公开(公告)号：US20170138891A1

公开(公告)日：2017-05-18

申请号：US15347886

申请日：2016-11-10

Applicant: NGK INSULATORS, LTD.

Inventor： Noriko HIRATA ,  Taku OKAMOTO ,  Yuki NAKAYAMA ,  Osamu NAKASONE

IPC: G01N27/407

Abstract: A gas sensor capable of measuring a high concentration range is provided. A sensing electrode provided in a sensor element of a mixed-potential gas sensor for measuring the concentration of a predetermined component in a measurement gas is formed of a cermet including a noble metal and an oxygen-ion conductive solid electrolyte. The noble metal includes Pt and Au. A Au abundance ratio, which is an area ratio of a portion covered with Au to a portion at which Pt is exposed in a surface of noble metal particles forming the sensing electrode, is 0.1 or more and less than 0.3.

公开(公告)号：US20140134514A1

公开(公告)日：2014-05-15

申请号：US13875482

申请日：2013-05-02

Applicant: NGK Insulators, Ltd.

Inventor： Taku OKAMOTO ,  Makoto OHMORI

IPC: H01M8/02

CPC classification number: H01M8/0247 ,  H01M8/1226 ,  H01M8/2428 ,  H01M8/2432 ,  H01M2008/1293

Abstract: Provided is a fuel cell as a fired body including a porous plate-like support substrate having a gas flow path formed therein, and a power generation element part provided on a principal surface of the support substrate, the power generation element part including at least a fuel electrode, a solid electrolyte, and an air electrode laminated in this order. The generation of cracks in the support substrate has a strong correlation with a “surface roughness of a wall surface of a gas flow” of the fuel cell in a state of a reductant. When the surface roughness of the wall surface of the gas flow path is 0.16 to 5.2 in terms of an arithmetic average roughness Ra in a state in which the fuel cell is a reductant that has been subjected to heat treatment in a reducing atmosphere, the generation of the cracks can be suppressed.

Abstract translation: 提供一种作为燃烧体的燃料电池，其包括形成有气体流路的多孔板状支撑基板和设置在支撑基板的主面上的发电元件部，发电元件部至少包括 燃料电极，固体电解质和空气电极。 支撑基板中的裂纹的产生与还原剂的状态下的燃料电池的“气体流动的壁面的表面粗糙度”有很强的相关性。 在燃料电池为在还原气氛中进行了热处理的还原剂的状态下，以流量平均粗糙度Ra计，气体流路的壁面的表面粗糙度为0.16〜5.2， 的裂缝可以被抑制。

公开(公告)号：US20230296553A1

公开(公告)日：2023-09-21

申请号：US18183425

申请日：2023-03-14

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Taku OKAMOTO

IPC: G01N27/407 ,  G01N27/41

CPC classification number: G01N27/4078 ,  G01N27/41 ,  G01N27/4077

Abstract: A casing of a gas sensor having a reference gas space therein includes: an outer tube into which an end portion of a sensor element protrudes; and a seal member fit into an end portion of the outer tube to seal the reference gas space, the sensor element includes: a first electrode lead portion including a first electrode lead to electrically connect an outside and at least one out-of-space pump electrode and a first lead insulating layer covering the first electrode lead; and a second electrode lead portion including a second electrode lead that can electrically connect the outside and a measurement electrode and a second lead insulating layer covering the second electrode lead, and A/B