公开(公告)号：US20210208096A1

公开(公告)日：2021-07-08

申请号：US17207986

申请日：2021-03-22

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Mika KAI ,  Ryo ONISHI ,  Saki SUZUKI ,  Takashi HINO

IPC: G01N27/407 ,  C04B38/00 ,  G01N27/41 ,  G01N27/419

Abstract: A sensor element includes: an inner protective layer having a porosity of 30% to 65% on two main surfaces; an intermediate protective layer, at least a part of which has contact with the inner layer, and having a porosity of 25% to 80%, which is equal to or smaller than the porosity of the inner layer; and an outer protective layer surrounding an element base on an outermost periphery on the one end portion of the sensor element, having contact with the intermediate and the inner layer, having contact with a leading end surface of the element base or the intermediate layer on the leading end surface, and having a porosity of 15% to 30%, which is smaller than the porosity of the intermediate layer, wherein a difference of porosity between the inner and the outer layer is 10% to 50%.

公开(公告)号：US20210140916A1

公开(公告)日：2021-05-13

申请号：US17093676

申请日：2020-11-10

Applicant: NGK INSULATORS, LTD.

Inventor： Shotaro NIIZUMA ,  Yusuke WATANABE ,  Toshihiro HIRAKAWA ,  Hayami AOTA

IPC: G01N27/407 ,  G01N27/406 ,  G01N33/00 ,  G01N27/409 ,  G01N27/41

Abstract: A gas sensor includes a sensor element, an elastic insulating member, a plurality of lead wires, a plurality of metal terminals, and a ceramic housing. The plurality of lead wires are inserted in the elastic insulating member. The plurality of metal terminals each have a first end electrically connected to the sensor element, and a second end electrically connected to a corresponding one of the plurality of lead wires. The ceramic housing includes a plurality of insertion portions each including a through hole in which a corresponding one of the plurality of metal terminals is inserted, and at least one of the plurality of insertion portions has a different height from other insertion portions.

公开(公告)号：US20210109058A1

公开(公告)日：2021-04-15

申请号：US17128361

申请日：2020-12-21

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Takayuki SEKIYA

IPC: G01N27/41 ,  G01N1/24 ,  G01R19/00 ,  G01N27/407

Abstract: In a gas sensor, oxygen pumping control is performed to pump oxygen from the surroundings of an outer side pump electrode into the surroundings of a reference electrode. In addition, during execution of the oxygen pumping control, a pump current Ip2 is measured when oxygen originating from NOx is pumped out from the surroundings of a measurement electrode so that a voltage V2 reaches a target voltage V2*. Then, the NOx concentration of a measurement-object gas is calculated based on Ip2. In the gas sensor, the NOx concentration is corrected based on DVref which is the difference between Vref1 and Vref2, Vref1 across the reference electrode and the outer side pump electrode when the oxygen pumping control is not performed, Vref2 across the reference electrode and the outer side pump electrode when the oxygen pumping control is performed.

公开(公告)号：US20200209185A1

公开(公告)日：2020-07-02

申请号：US16715110

申请日：2019-12-16

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Takashi HINO ,  Mika KAI

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

Abstract: A sensor element includes: an element base including: a ceramic body made of an oxygen-ion conductive solid electrolyte, and having an inlet at one end portion thereof; at least one internal chamber located inside the ceramic body, and communicating with the gas inlet; and an electrochemical pump cell including an outer electrode, an inner electrode facing the chamber, and a solid electrolyte therebetween, and a porous leading-end protective layer covering a leading end surface and four side surfaces in a predetermined range of the element base on the one end portion, wherein the protective layer has an extension extending into the gas inlet and fixed to an inner wall surface of the ceramic body demarcating the gas inlet, and a gap communicating with the gas inlet is located in the protective layer, with demarcated by a portion of the protective layer continuous with the extension.

公开(公告)号：US20200080959A1

公开(公告)日：2020-03-12

申请号：US16686812

申请日：2019-11-18

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Takao MURASE ,  Masashi YASUI

IPC: G01N27/406 ,  H05B3/26 ,  H05B3/00 ,  H05B1/02

Abstract: A heater section includes a plate-like ceramic body (a first substrate layer 1, a second substrate layer 2, and a third substrate layer 3) having a longitudinal direction (front-rear direction) and a short-length direction (left-right direction), and a heater 72 disposed within the plate-like ceramic body and including a lead section 79 and a heating section 76 connected to the lead section 79. The heating section 76 includes a straight portion 78 extending along the longitudinal direction, and a lead side curved portion 77b connected to one of the ends of the straight portion 78 closer to the lead section 79. The lead side curved portion 77b has a lower resistance per unit length than the straight portion 78 at one or more temperatures in the range of 700° C. to 900° C.

公开(公告)号：US20200041442A1

公开(公告)日：2020-02-06

申请号：US16520466

申请日：2019-07-24

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Takayuki SEKIYA ,  Shota KAGEYAMA

IPC: G01N27/417 ,  G01N27/407

Abstract: A sensor element includes: a main pump cell constituted by an inner electrode provided to face a first inner space into which a measurement gas is introduced, an external electrode provided on an element surface, and a solid electrolyte therebetween; and a measurement pump cell constituted by a measurement electrode provided to face a second inner space communicated with the first inner space, an external electrode, and a solid electrolyte therebetween. A diffusion resistance from a gas inlet to the inner electrode is 200 to 1000 cm−1. For the first inner space and a unit electrode part of the inner electrode, a space length is 2.5 to 10 mm, a space thickness is 50 to 300 μm, an electrode length/the space length is 0.5 to 1.0, and an electrode width/the space width is 0.5 to 1.0.

公开(公告)号：US20190285575A1

公开(公告)日：2019-09-19

申请号：US16351741

申请日：2019-03-13

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Takayuki SEKIYA

IPC: G01N27/41 ,  G01N27/30 ,  G01N27/407 ,  G01N27/409

Abstract: A sensor element includes: a main pump cell constituted by an inner pump electrode facing a first inner space into which a measurement gas is introduced, an external pump electrode provided on an element surface, and a solid electrolyte located therebetween; and a measurement pump cell constituted by the measurement electrode facing a second inner space which is communicated with the first inner space and functioning as a reduction catalyst for NOx, and a solid electrolyte located therebetween. The inner pump electrode has a planar shape in which two parts of a front end part relatively having a large area and a rear end part relatively having a small area are sequentially connected in this order from an upstream side in a longitudinal direction of the sensor element while satisfying requirements of a predetermined size and area.

公开(公告)号：US20190285572A1

公开(公告)日：2019-09-19

申请号：US16351562

申请日：2019-03-13

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Takayuki SEKIYA ,  Yuki NAKAYAMA ,  Shota KAGEYAMA

IPC: G01N27/407 ,  G01N27/30 ,  G01N27/409 ,  G01N27/41

Abstract: A sensor element includes: a main pump cell constituted by an inner pump electrode facing the first inner space into which a measurement gas is introduced, an external pump electrode provided on an element surface, and a solid electrolyte located therebetween; a measurement electrode facing a second inner space communicating with the first inner space and functioning as a reduction catalyst for NOx; and a measurement pump cell constituted by the measurement electrode, the external pump electrode, and a solid electrolyte located therebetween. A diffusion resistance from the gas inlet to the inner pump electrode ranges from 200-1000 cm−1, a resistance of the main pump cell is equal to or smaller than 150Ω, a distance between the electrodes ranges from 0.1-0 6 mm, and the inner pump electrode which is a cermet made of an Au—Pt alloy and ZrO2 has an area ranging from 5-20 mm2.

公开(公告)号：US20180284053A1

公开(公告)日：2018-10-04

申请号：US15938126

申请日：2018-03-28

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Tetsuya ISHIKAWA

IPC: G01N27/407

Abstract: A gas sensor according to the present application includes a detecting device that detects a specific gas concentration of a measurement-object gas based on an electromotive force generated between a reference electrode and a measurement electrode; and a reference gas regulating device that flows an oxygen pumping current between the reference electrode and a measurement-object gas side electrode and pumps oxygen from around the measurement-object gas side electrode to around the reference electrode, wherein when the average value of the oxygen pumping current is P and the limiting current value of a reference gas introduction layer when oxygen is pumped from around the reference electrode to around the measurement-object gas side electrode is Q, the ratio Q/P is from 0.8 to 10.

公开(公告)号：US20250110076A1

公开(公告)日：2025-04-03

申请号：US18979857

申请日：2024-12-13

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke WATANABE ,  Ryo HASHIKAWA

IPC: G01N27/407 ,  G01N27/406 ,  G01N27/41 ,  G01N33/00

Abstract: A sensor element includes an element body, a reference electrode, a measurement-object gas side electrode, a first conducting section that has a reference electrode terminal and a reference electrode lead, and a lead insulation layer. The reference electrode lead is configured to flow a reference gas, which serves as a reference for detecting the specific gas concentration in the measurement-object gas, to the reference electrode. A region of 50% or more, from an end on the reference electrode side, of the total area of the lead insulation layer in a planar view is configured as a dense region with a porosity of 5% or less.