公开(公告)号：US12216075B2

公开(公告)日：2025-02-04

申请号：US17482648

申请日：2021-09-23

Applicant: NGK INSULATORS, LTD.

Inventor： Ryo Onishi ,  Yasuhide Kojima ,  Yusuke Watanabe

IPC: G01N27/407 ,  G01M15/10

Abstract: A gas sensor element includes an element body including an oxygen-ion-conductive solid electrolyte layer; and a protective layer that covers at least part of the element body, and has a thermal conductivity ratio R of 1.6 or higher, the thermal conductivity ratio R (=λs/λt) being a surface direction thermal conductivity λs [W/m K] to a thickness direction thermal conductivity λt [W/m K].

公开(公告)号：US12066396B2

公开(公告)日：2024-08-20

申请号：US17189295

申请日：2021-03-02

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke Watanabe ,  Kengo Terasawa ,  Shiho Iwai

IPC: G01N27/41 ,  G01N27/407

CPC classification number: G01N27/41 ,  G01N27/4076

Abstract: In a sensor element for a limiting-current type gas sensor measuring concentration of NOx in a measurement gas, an inner pump electrode located to face a first internal space communicating with a gas inlet through which the measurement gas is introduced from an external space under predetermined diffusion resistance is made of a cermet of a Pt—Au alloy and zirconia, and the inner pump electrode is located, from among surfaces defining the first internal space, at least on a surface farthest from a heater part in a thickness direction of the element, and is not located on a surface closest to the heater part in the thickness direction.

公开(公告)号：US11808730B2

公开(公告)日：2023-11-07

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 ,  G01N27/409

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

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：US11525802B2

公开(公告)日：2022-12-13

申请号：US16819925

申请日：2020-03-16

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke Watanabe ,  Shiho Iwai

IPC: G01N27/409 ,  G01N27/407 ,  G01N27/419 ,  G01N27/30 ,  G01N27/41

Abstract: A gas sensor includes a sensor element, a detection device, a reference gas regulating device. The sensor element includes an element body having disposed therein a measurement-object gas flow section, a measurement-object-gas-side electrode disposed in or out of the element body, a reference electrode disposed within the element body, and a reference gas introducing section that allows a reference gas to be introduced thereinto and to flow therethrough to the reference electrode. The reference gas regulating device allows an oxygen pump-in current to flow between the reference electrode and the measurement-object-gas-side electrode to pump oxygen into around the reference electrode from around the measurement-object-gas-side electrode. A ratio R1/R2 of a reaction resistance R1 of the reference electrode to a diffusion resistance R2 of the reference gas introducing section is greater than or equal to 0.1 and less than or equal to 2.0.

公开(公告)号：US20220308007A1

公开(公告)日：2022-09-29

申请号：US17702014

申请日：2022-03-23

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke Watanabe

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

Abstract: A control method of a gas sensor including a sensor element and an activity determining part includes a temperature raising step of heating the sensor element by a heater of the sensor element to raise a temperature of the sensor element up to an active temperature at which the activity determining part determines that the sensor element is in a measurable active state; a prior driving step of raising the temperature of the sensor element by the heater from the active temperature up to a steady driving temperature, and operating a main pump cell and a measurement pump cell of the sensor element to detect NOx in the measurement-object gas; and a steady driving step of maintaining the temperature of the sensor element by the heater at the steady driving temperature, and operating the main pump cell and the measurement pump cell to continuously detect NOx in the measurement-object gas.

公开(公告)号：US11415544B2

公开(公告)日：2022-08-16

申请号：US16522718

申请日：2019-07-26

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke Watanabe ,  Mika Kai ,  Ryo Onishi ,  Saki Suzuki

IPC: G01N27/41 ,  G01N27/407

Abstract: A sensor element includes: an element base including: a ceramic body made of an oxygen-ion conductive solid electrolyte, and having a gas inlet at one end portion thereof; at least two internal chambers located inside the ceramic body, and communicating with the gas inlet under predetermined diffusion resistance; an electrochemical pump cell including an electrode located on an outer surface of the ceramic body, an electrode facing the internal chambers, and solid electrolytes located therebetween; and a heater buried in the ceramic body; and a porous leading-end protective layer surrounding a first range at least including a part from a leading end surface to two internal chambers close to the gas inlet of the element base. A single heat insulating space is interposed between the leading-end protective layer and a portion of the element base in which the two internal chambers are located.

公开(公告)号：US11360043B2

公开(公告)日：2022-06-14

申请号：US16522720

申请日：2019-07-26

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke Watanabe ,  Mika Kai ,  Ryo Onishi ,  Saki Suzuki

IPC: G01N27/41 ,  G01N27/407

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 inlet under predetermined diffusion resistance; an electrochemical pump cell including an electrode located on an outer surface of the ceramic body, an electrode facing the internal chamber, and a solid electrolyte located therebetween; and a heater buried in the ceramic body; and a porous leading-end protective layer surrounding a first range at least including a leading end surface and a region to be coped with water-induced cracking specified in advance. A single heat insulating space is interposed between the leading-end protective layer and a whole side surface of the element base at least in the above region.

公开(公告)号：US11237129B2

公开(公告)日：2022-02-01

申请号：US15938242

申请日：2018-03-28

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke Watanabe ,  Shiho Iwai

IPC: G01N27/41 ,  G01N27/407 ,  G01N27/30 ,  G01N27/406

Abstract: A sensor element includes a layered body that includes a measurement-object gas flowing portion which a measurement object gas is introduced and flowed in and a reference electrode that is formed inside of the layered body and a reference gas introducing layer made of a porous material that introduces a reference gas being used as a standard for detection of a specific gas concentration in the measurement-object gas and that flows the reference gas to the reference electrode, the reference gas introducing layer including an inlet portion serving as an inlet of the reference gas and one or more gas flowing spaces provided over a region from the inlet portion to the reference electrode in a direction in which the reference gas is flowed.

公开(公告)号：US10900920B2

公开(公告)日：2021-01-26

申请号：US16434594

申请日：2019-06-07

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke Watanabe ,  Takao Murase ,  Masashi Yasui

IPC: G01N27/00 ,  G01N27/02 ,  G01N27/407 ,  G01N33/00

Abstract: A gas sensor 10 includes a tubular protective cover 30 having an element chamber 37 therein and configured to allow a measured gas to flow from the outside into the element chamber 37; and a long sensor element 20 including a detecting portion 23 located in the element chamber 37 and configured to detect a specified gas concentration in the measured gas. An inclination angle θt of an axial direction of the sensor element 20 (i.e., a direction parallel to an element axis A1) in the element chamber 37 with respect to an axial direction of the protective cover 30 (i.e., a direction parallel to a cover axis A2) is 1° or greater.

公开(公告)号：US10527578B2

公开(公告)日：2020-01-07

申请号：US15238855

申请日：2016-08-17

Applicant: NGK INSULATORS, LTD.

Inventor： Yusuke Watanabe ,  Takao Murase ,  Masashi Yasui

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

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.