Patents by Inventor Kiyomi Kobayashi

Kiyomi Kobayashi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10228342
    Abstract: A gas sensor has a gas sensor element which has a solid electrolyte body, a reference electrode and a measuring electrode. The solid electrolyte body contains partially stabilized zirconia as a main component in which zirconia is stabilized by stabilizer agent. Particle boundary parts are formed between crystal particles made of the partially stabilized zirconia. The particle boundary parts are made of a metal element such as yttria derived from the stabilizer agent, an alumina component and a silica component. A total content of the alumina component and the silica component in the particle boundary parts in the solid electrolyte body is within a range of 0.01 mass % to 1 mass % in terms of oxide in the solid electrolyte body. A ratio of the alumina component to the silica component in the particle boundary parts 12 is within a range of 0.2 to 2.0 in terms of oxide.
    Type: Grant
    Filed: December 10, 2015
    Date of Patent: March 12, 2019
    Assignee: DENSO CORPORATION
    Inventors: Kiyomi Kobayashi, Kazuki Yagi, Makoto Noguchi
  • Patent number: 9624133
    Abstract: A solid electrolyte is made of zirconia grains containing yttria and alumina grains dispersed in the zirconia grains. In the solid electrolyte, the yttria content per zirconia content is within a range of 2 to 10 mol. %, the relative density is not less than 93%, and the average particle size Rz of the zirconia grains is not more than 2 ?m, an average particle size Ra of the alumina grains is not more than 1 ?m. The average particle size Ra of the alumina grains is smaller than the average particle size Rz of the zirconia grains. An average distance value ALa between the alumina grains is not more than 2 ?m, and a standard deviation SLa thereof is not more than 0.8. The solid electrolyte satisfies a relationship of (SLa/ALa)×Rz?0.9.
    Type: Grant
    Filed: February 4, 2010
    Date of Patent: April 18, 2017
    Assignees: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Kazuhiko Koike, Kiyomi Kobayashi
  • Patent number: 9618473
    Abstract: A gas sensor has a cylindrical housing case, a gas sensor element as a sensor component, and a filler portion. The filler portion is formed between the inner surface of the cylindrical housing case and the outer surface of the gas sensor element. The filler portion is filled with filler powder composed of talc as a layered compound. Talc is a principal ingredient of the filler powder. The space formed between the cylindrical housing case and the gas sensor element is sealed with the filler powder in the filler portion. The filler powder in the filler portion has a degree of c-axis orientation within a range of 60% to 85%, The filler powder in the filler portion has a porosity of not more than 10%.
    Type: Grant
    Filed: June 7, 2012
    Date of Patent: April 11, 2017
    Assignee: DENSO CORPORATION
    Inventor: Kiyomi Kobayashi
  • Publication number: 20160169830
    Abstract: A gas sensor has a gas sensor element which has a solid electrolyte body, a reference electrode and a measuring electrode. The solid electrolyte body contains partially stabilized zirconia as a main component in which zirconia is stabilized by stabilizer agent. Particle boundary parts are formed between crystal particles made of the partially stabilized zirconia. The particle boundary parts are made of a metal element such as yttria derived from the stabilizer agent, an alumina component and a silica component. A total content of the alumina component and the silica component in the particle boundary parts in the solid electrolyte body is within a range of 0.01 mass % to 1 mass % in terms of oxide in the solid electrolyte body. A ratio of the alumina component to the silica component in the particle boundary parts 12 is within a range of 0.2 to 2.0 in terms of oxide.
    Type: Application
    Filed: December 10, 2015
    Publication date: June 16, 2016
    Inventors: Kiyomi KOBAYASHI, Kazuki YAGI, Makoto NOGUCHI
  • Patent number: 8834693
    Abstract: The present invention provides, as one aspect, a gas sensor element including a solid electrolytic substance having a bottomed cylindrical shape and oxygen ion conductivity, a reference electrode arranged on an inner side surface of the solid electrolytic substance, a measuring electrode arranged on an outer side surface of the solid electrolytic substance, and a protective layer which covers the outer side surface of the solid electrolytic substance together with the measuring electrode and which allows gas to be measured to pass through the protective layer, wherein an end side of the gas sensor element is formed of a leg portion whose profile line is straight on an axial cross section and a bottom portion whose profile line is curved, and the film thickness of the protective layer of the bottom portion is larger than the film thickness of the protective layer of the leg portion.
    Type: Grant
    Filed: December 23, 2009
    Date of Patent: September 16, 2014
    Assignee: Denso Corporation
    Inventors: Zhenzhou Su, Kiyomi Kobayashi, Motoaki Satou
  • Patent number: 8597481
    Abstract: A gas sensor element with a bottom part is composed of at least a solid electrolyte body of oxygen ion conductivity, a reference electrode, a detection electrode, an electrode protection layer which supports noble metal catalyst, and a heater. The electrode protection layer is composed of a covering layer, a catalyst layer and a poisoning layer. A quantity of the noble metal catalyst supported in the electrode protection layer at the bottom part of the gas sensor element is larger than that in the electrode protection layer at a leg part of the gas sensor. The bottom part of the gas sensor element has a high temperature rising speed more than the leg part when the heater generates heat energy.
    Type: Grant
    Filed: May 13, 2011
    Date of Patent: December 3, 2013
    Assignee: Denso Corporation
    Inventors: Zhenzhou Su, Kiyomi Kobayashi
  • Publication number: 20120312685
    Abstract: A gas sensor has a cylindrical housing case, a gas sensor element as a sensor component, and a filler portion. The filler portion is formed between the inner surface of the cylindrical housing case and the outer surface of the gas sensor element. The filler portion is filled with filler powder composed of talc as a layered compound. Talc is a principal ingredient of the filler powder. The space formed between the cylindrical housing case and the gas sensor element is sealed with the filler powder in the filler portion. The filler powder in the filler portion has a degree of c-axis orientation within a range of 60% to 85%, The filler powder in the filler portion has a porosity of not more than 10%.
    Type: Application
    Filed: June 7, 2012
    Publication date: December 13, 2012
    Applicant: Denso Corporation
    Inventor: Kiyomi KOBAYASHI
  • Patent number: 8168053
    Abstract: A gas sensing member has a unit structure and a porous protective layer disposed on the unit structure. The unit structure has a solid electrolyte body, a gas measurement electrode disposed on a surface of the body and exposed to a measured gas entering at a gas inlet, a reference gas electrode disposed on another surface of the body and exposed to a reference gas, and a heater disposed close to the body. The heater has a heater substrate and heating elements disposed in the heater substrate. The heating elements heat the body. The heater substrate has side corner areas placed on side corners of the unit structure and being adjacent to the heating elements. The protective layer is disposed on the gas inlet such that the side corner areas are not covered with the protective layer and are directly exposed to the measured gas.
    Type: Grant
    Filed: January 12, 2007
    Date of Patent: May 1, 2012
    Assignee: Denso Corporation
    Inventors: Kiyomi Kobayashi, Makoto Nakae, Toshikazu Hirose
  • Publication number: 20120061231
    Abstract: A gas sensor element includes a solid electrolyte body having oxygen ion conductivity and electrode layers formed on both surfaces of the solid electrolyte body configuring a pair of electrodes. The gas sensor element detects concentration of a selected component included in a measured gas. In the gas sensor element, closed pores having an average pore diameter of 5 nm or more and 120 nm or less are dispersed in the electrode layers, porosity measured by cross-sectional observation of the electrode layers is 1% or more and 18% or less, and 90% or more of the closed pores is dispersed within metal grains forming the electrode layers.
    Type: Application
    Filed: September 8, 2011
    Publication date: March 15, 2012
    Applicant: DENSO CORPORATION
    Inventors: Kiyomi KOBAYASHI, Zhenzhou Su
  • Publication number: 20110278169
    Abstract: A gas sensor element with a bottom part is composed of at least a solid electrolyte body of oxygen ion conductivity, a reference electrode, a detection electrode, an electrode protection layer which supports noble metal catalyst, and a heater. The electrode protection layer is composed of a covering layer, a catalyst layer and a poisoning layer. A quantity of the noble metal catalyst supported in the electrode protection layer at the bottom part of the gas sensor element is larger than that in the electrode protection layer at a leg part of the gas sensor. The bottom part of the gas sensor element has a high temperature rising speed more than the leg part when the heater generates heat energy.
    Type: Application
    Filed: May 13, 2011
    Publication date: November 17, 2011
    Applicant: DENSO CORPORATION
    Inventors: Zhenzhou Su, Kiyomi Kobayashi
  • Patent number: 8058592
    Abstract: A gas sensor is equipped with a built-in ceramic heater. The gas sensor detects the concentration of a predetermined gas component contained in the exhaust gas. The ceramic heater has a heater base member made of ceramic, a heating element formed in the inside of the heater base material, and a pair of external electrode pads that is electrically connected to the output terminals for the outer leads. The external electrode pads, the heating element, and the heater leads are made of base metal. The outer surface of each external electrode pad is covered only with a dense protective film made of noble metal such as gold (Au), silver (Ag), platinum (Pt), rhodium (Rh), and palladium (Pd).
    Type: Grant
    Filed: March 25, 2008
    Date of Patent: November 15, 2011
    Assignee: Denso Corporation
    Inventors: Takehito Kimata, Kiyomi Kobayashi
  • Publication number: 20100200427
    Abstract: A solid electrolyte is made of zirconia grains containing yttria and alumina grains dispersed in the zirconia grains. In the solid electrolyte, the yttria content per zirconia content is within a range of 2 to 10 mol. %, the relative density is not less than 93%, and the average particle size Rz of the zirconia grains is not more than 2 ?m, an average particle size Ra of the alumina grains is not more than 1 ?m. The average particle size Ra of the alumina grains is smaller than the average particle size Rz of the zirconia grains. An average distance value ALa between the alumina grains is not more than 2 ?m, and a standard deviation SLa thereof is not more than 0.8. The solid electrolyte satisfies a relationship of (SLa/ALa)×Rz?0.9.
    Type: Application
    Filed: February 4, 2010
    Publication date: August 12, 2010
    Applicants: NIPPON SOKEN, INC., DENSO CORPORATION
    Inventors: Kazuhiko Koike, Kiyomi Kobayashi
  • Publication number: 20100163411
    Abstract: The present invention provides, as one aspect, a gas sensor element including a solid electrolytic substance having a bottomed cylindrical shape and oxygen ion conductivity, a reference electrode arranged on an inner side surface of the solid electrolytic substance, a measuring electrode arranged on an outer side surface of the solid electrolytic substance, and a protective layer which covers the outer side surface of the solid electrolytic substance together with the measuring electrode and which allows gas to be measured to pass through the protective layer, wherein an end side of the gas sensor element is formed of a leg portion whose profile line is straight on an axial cross section and a bottom portion whose profile line is curved, and the film thickness of the protective layer of the bottom portion is larger than the film thickness of the protective layer of the leg portion.
    Type: Application
    Filed: December 23, 2009
    Publication date: July 1, 2010
    Applicant: DENSO CORPORATION
    Inventors: Zhenzhou SU, Kiyomi KOBAYASHI, Motoaki SATOU
  • Patent number: 7607339
    Abstract: A ceramic laminate body, a gas sensor element employing such a ceramic laminate body and related manufacturing method are disclosed as including first and second ceramic sheets, made of material compositions different from each other, and an intermediate bonding layer, bonding the first and second ceramic sheets to each other so as to form a closed hollow space between the first and second ceramic sheets. The intermediate bonding layer has a multilayer structure including first and second unit intermediate layers laminated on each other such that innermost end portions of the first and second unit intermediate layers are displaced from each other to adapt a difference in degreasing contraction rates of associated component parts.
    Type: Grant
    Filed: February 15, 2007
    Date of Patent: October 27, 2009
    Assignee: Denso Corporation
    Inventors: Makoto Nakae, Shoichiro Emmei, Kiyomi Kobayashi
  • Publication number: 20080237065
    Abstract: A gas sensor is equipped with a built-in ceramic heater. The gas sensor detects the concentration of a predetermined gas component contained in the exhaust gas. The ceramic heater has a heater base member made of ceramic, a heating element formed in the inside of the heater base material, and a pair of external electrode pads that is electrically connected to the output terminals for the outer leads. The external electrode pads, the heating element, and the heater leads are made of base metal. The outer surface of each external electrode pad is covered only with a dense protective film made of noble metal such as gold (Au), silver (Ag), platinum (Pt), rhodium (Rh), and palladium (Pd).
    Type: Application
    Filed: March 25, 2008
    Publication date: October 2, 2008
    Applicant: DENSO CORPORATION
    Inventors: Takehito KIMATA, Kiyomi KOBAYASHI
  • Publication number: 20080210575
    Abstract: In an oxygen sensor for installation in the exhaust gas system of a vehicle for detecting a concentration of NOx in exhaust gas downstream from a catalytic converter, in which the exhaust gas is passed through a protective layer to an electrode disposed at one side of a solid electrolyte in a sensor element of the oxygen sensor, the protective layer is formed with a combination of values of thickness and porosity which provide improved sensitivity in detecting low levels of NOx in the exhaust gas.
    Type: Application
    Filed: February 28, 2008
    Publication date: September 4, 2008
    Applicant: DENSO CORPORATION
    Inventors: Takahiko NONOGAKI, Kiyomi Kobayashi, Takehito Kimata, Zhenzhou Su
  • Publication number: 20080190767
    Abstract: A laminated gas sensor includes a solid electrolyte layer, a measurement gas chamber, a reference gas chamber, a measurement gas chamber formation layer, and a reference gas chamber formation layer. The measurement gas chamber formation layer has an opposite pair of inner side surfaces that extend in a longitudinal direction of the solid electrolyte layer and face each other in a lateral direction of the solid electrolyte layer through the measurement gas chamber. The reference gas chamber formation layer has an opposite pair of inner side surfaces that extend in the longitudinal direction and face each other in the lateral direction through the reference gas chamber. Further, at least one of the inner side surfaces of the measurement gas chamber formation layer is located more inside the laminated gas sensor than a corresponding one of the inner side surfaces of the reference gas chamber formation layer in the lateral direction.
    Type: Application
    Filed: December 19, 2007
    Publication date: August 14, 2008
    Applicant: DENSO CORPORATION
    Inventors: Makoto NAKAE, Kiyomi Kobayashi
  • Publication number: 20070246361
    Abstract: A gas sensor and method of manufacturing the gas sensor are disclosed. The gas sensor comprises a gas sensing element, an insulating element holder having an element inserting bore through which the gas sensing element axially extends, a housing fixedly supporting the insulating element holder, an airtight sealant and a cushioning filler. Ceramic slurry, composed of at least ceramic powder and binder, is filled in an area between the gas sensing element and the insulating element holder on a leading end portion of the element inserting bore and fired to form a cushioning filler. The ceramic slurry contains 47 to 53 wt % of ceramic solids for a gross weight of ceramic slurry and a binder laying in a value ranging from 5 to 10 wt % for a weight of the ceramic solids.
    Type: Application
    Filed: April 9, 2007
    Publication date: October 25, 2007
    Applicant: DENSO CORPORATION
    Inventors: Toshikazu Hirose, Kiyomi Kobayashi, Makoto Nakae
  • Publication number: 20070214865
    Abstract: A ceramic laminate body, a gas sensor element employing such a ceramic laminate body and related manufacturing method are disclosed as including first and second ceramic sheets, made of material compositions different from each other, and an intermediate bonding layer, bonding the first and second ceramic sheets to each other so as to form a closed hollow space between the first and second ceramic sheets. The intermediate bonding layer has a multilayer structure including first and second unit intermediate layers laminated on each other such that innermost end portions of the first and second unit intermediate layers are displaced from each other to adapt a difference in degreasing contraction rates of associated component parts.
    Type: Application
    Filed: February 15, 2007
    Publication date: September 20, 2007
    Applicant: DENSO CORPORATION
    Inventors: Makoto Nakae, Shoichiro Emmei, Kiyomi Kobayashi
  • Publication number: 20070170057
    Abstract: A gas sensing member has a unit structure and a porous protective layer disposed on the unit structure. The unit structure has a solid electrolyte body, a gas measurement electrode disposed on a surface of the body and exposed to a measured gas entering at a gas inlet, a reference gas electrode disposed on another surface of the body and exposed to a reference gas, and a heater disposed close to the body. The heater has a heater substrate and heating elements disposed in the heater substrate. The heating elements heat the body. The heater substrate has side corner areas placed on side corners of the unit structure and being adjacent to the heating elements. The protective layer is disposed on the gas inlet such that the side corner areas are not covered with the protective layer and are directly exposed to the measured gas.
    Type: Application
    Filed: January 12, 2007
    Publication date: July 26, 2007
    Applicant: Denso Corporation
    Inventors: Kiyomi Kobayashi, Makoto Nakae, Toshikazu Hirose