Patents by Inventor Tomohiro Tajima

Tomohiro Tajima 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: 9360448
    Abstract: A gas sensor (1) includes at least a sensor element (12) which measures the concentration of a specific gas component, a housing (13) which accommodates the sensor element (12), and a base portion (21) which is attached to the housing and is formed of resin. The base portion includes a first base portion (22) which is a portion of the base portion located on the side toward the housing and which is molded integrally with the housing, and a second base portion (23) which is molded separately from the first base portion, which is a portion of the base portion located opposite the housing, and which has a connector portion (23c) in which a plurality of terminals (26) electrically connected to the sensor element are disposed such that they extend in a direction intersecting the insertion direction of the sensor element.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: June 7, 2016
    Assignee: NGK SPARK PLUG CO., LTD.
    Inventors: Kunihiko Yonezu, Hisaharu Nishio, Norimasa Osawa, Tomohiro Tajima
  • Patent number: 9322680
    Abstract: A thin plate member which has a groove portion recessed toward the inside in a radial direction with a gap interposed between the thin plate member and the outer surface of a site on the front end side of a main body section. At least one end of the thin plate member is joined to the outer surface of the main body section and is provided radially outside the site on the front end side of the main body section. A seal member is disposed in the groove portion and has elasticity due to resin. Since the gap functions as a heat-insulating layer and is interposed between the seal member and the main body section, heat conduction from the main body section, that is, heat conduction through a first pathway is reduced, and thus deterioration of the seal member due to heat is suppressed.
    Type: Grant
    Filed: May 23, 2013
    Date of Patent: April 26, 2016
    Assignee: NGK SPARK PLUG CO., LTD.
    Inventors: Kunihiko Yonezu, Toshiya Matsuoka, Norimasa Osawa, Hisaharu Nishio, Tomohiro Tajima
  • Patent number: 9032779
    Abstract: A gas sensor (1) has an inner protector (120) and an outer protector (110); the inner protector (120) has an inner wall portion (160) having an inner gas inlet (170) for introducing gas to be measured into the interior of the inner protector (120); the outer protector (110) has an outer wall portion (130) having an outer gas inlet (140) for introducing the gas to be measured into the interior of the outer protector (110); a clearance of 1.35 mm or less is provided between the detection portion (11) and at least a portion of the inner wall portion (160); and when the gas sensor (1) is in use, the inner protector (120) is higher in temperature than the outer protector (110).
    Type: Grant
    Filed: October 20, 2009
    Date of Patent: May 19, 2015
    Assignee: NGK SPARK PLUG CO., LTD.
    Inventors: Masanori Otsubo, Takaya Yoshikawa, Tomohiro Tajima, Masao Tsuzuki
  • Patent number: 8874349
    Abstract: A sensor control apparatus including a gas sensor having a sensor element, a housing and a base part formed of a resin. The apparatus includes a heating part and a control part. When the control part determines that a predetermined automatic stop condition has been satisfied, the control part switches from a control for maintaining the temperature of the sensor element at an activating temperature to a control in a stop state for reducing at least one of voltage and current supplied to the heating part so as to set a temperature of the base part to a value equal to or lower than a shape holding temperature of the resin. Also disclosed is a sensor control method for holding a temperature of a sensor element to an activating temperature.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: October 28, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Tomohiro Tajima, Satoshi Ishikawa, Kunihiko Yonezu
  • Patent number: 8806918
    Abstract: A gas sensor (200) includes a gas sensor element (10) extending in an axial direction (O), having a detection portion (11) provided at a front end thereof, and having electrode pads (12a) provided at a rear end thereof; connection terminals (31, 32) electrically connected to the respective electrode pads; and a cover (60, 61) covering the rear end of the gas sensor element and the connection terminals. The cover integrally has a connector portion (63) having an opening (63b) which allows an external connector to be inserted thereinto and removed therefrom in a predetermined direction, and has a connector terminal member (120) which can be inserted into the opening. The connector terminal member has a plurality of connector terminals (70) to be electrically connected to the respective connection terminals, and an insulator (121) integrally molded with the connector terminals. Also disclosed is a method for manufacturing the gas sensor.
    Type: Grant
    Filed: September 1, 2011
    Date of Patent: August 19, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Kunihiko Yonezu, Hisaharu Nishio, Takaya Yoshikawa, Tomohiro Tajima, Masao Tsuzuki
  • Patent number: 8764955
    Abstract: A gas sensor (200) includes a gas sensor element (10) extending in the direction of an axis O, and a housing (50) made of metal, radially surrounding the gas sensor element, and adapted for inserting at least partially into a sensor-mounting hole (350) of a mounting body (300). The gas sensor (200) further includes a resin member (60, 61) which radially surrounds the housing at least partially and having a contact portion (C) in contact with the housing that is at least partially disposed axially frontward with respect to the outer surface of the mounting body (300) around the sensor-mounting hole, and a heat sink member (80) that is in contact with the housing at an axial position the same as or located frontward of the axial position of the front end of the contact portion.
    Type: Grant
    Filed: July 21, 2011
    Date of Patent: July 1, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Takaya Yoshikawa, Tomohiro Tajima, Hisaharu Nishio, Masao Tsuzuki, Kunihiko Yonezu
  • Patent number: 8702934
    Abstract: A gas sensor including a gas sensor element that extends in an axial direction and has a detection section at a front-end side thereof, and an electrode pad at a rear-end side thereof; a connection terminal that is electrically connected to the electrode pad; and an insulated separator that extends along the axial direction and has an inserting hole into which the connection terminal is inserted. An element side section is arranged within the inserting hole and is connected the electrode pad, and an external circuit side section extends further to the outside in a diametrical direction than an outer surface of the separator through one or more first bending sections from the element side section.
    Type: Grant
    Filed: January 18, 2011
    Date of Patent: April 22, 2014
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Masao Tsuzuki, Tomohiro Tajima, Tomoki Fujii, Hisaharu Nishio, Takaya Yoshikawa, Kunihiko Yonezu
  • Patent number: 8603310
    Abstract: A sensor control apparatus (3) includes a full-range gas sensor composed of an oxygen concentration detection cell having a pair of electrodes (21, 22) and an oxygen pump cell having a pair of electrodes (19, 20). In an electric circuit section (30), an Ip current flowing between the electrodes (19, 20) is controlled such that an electromotive force Vs produced between the electrodes (21, 22) becomes equal to a reference voltage. The reference voltage is usually set to a first reference voltage. However, when the subject gas is air, the reference voltage is set to a second reference voltage. Humidity of the subject gas is detected on the basis of an error ?Ip between an Ip current detected when the reference voltage is set to the first reference voltage, and an Ip current detected when the reference voltage is set to the second reference voltage.
    Type: Grant
    Filed: April 19, 2010
    Date of Patent: December 10, 2013
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Noboru Ishida, Kentaro Mori, Tomohiro Tajima
  • Publication number: 20130312485
    Abstract: A thin plate member which has a groove portion recessed toward the inside in a radial direction with a gap interposed between the thin plate member and the outer surface of a site on the front end side of a main body section. At least one end of the thin plate member is joined to the outer surface of the main body section and is provided radially outside the site on the front end side of the main body section. A seal member is disposed in the groove portion and has elasticity due to resin. Since the gap functions as a heat-insulating layer and is interposed between the seal member and the main body section, heat conduction from the main body section, that is, heat conduction through a first pathway is reduced, and thus deterioration of the seal member due to heat is suppressed.
    Type: Application
    Filed: May 23, 2013
    Publication date: November 28, 2013
    Inventors: Kunihiko YONEZU, Toshiya MATSUOKA, Norimasa OSAWA, Hisaharu NISHIO, Tomohiro TAJIMA
  • Patent number: 8594908
    Abstract: An intake system for an internal combustion engine includes an intake passage connected with an intake port of the internal combustion engine; an EGR passage merged with the intake passage at a junction portion; a gas sensor attached to the intake passage and configured to detect a concentration of specific gas; and a control section configured to control the internal combustion engine on the basis of an output signal of the gas sensor. A diameter-enlarged portion having an inner diameter larger than an inner diameter of the junction portion is formed at a portion of the intake passage which is located on a downstream side of the junction portion. The gas sensor is located downstream from the diameter-enlarged portion.
    Type: Grant
    Filed: June 9, 2010
    Date of Patent: November 26, 2013
    Assignee: NGK Spark Plug Co., Ltd.
    Inventors: Takaya Yoshikawa, Tomohiro Tajima, Masao Tsuzuki
  • Publication number: 20130074578
    Abstract: A gas sensor (1) includes at least a sensor element (12) which measures the concentration of a specific gas component, a housing (13) which accommodates the sensor element (12), and a base portion (21) which is attached to the housing and is formed of resin. The base portion includes a first base portion (22) which is a portion of the base portion located on the side toward the housing and which is molded integrally with the housing, and a second base portion (23) which is molded separately from the first base portion, which is a portion of the base portion located opposite the housing, and which has a connector portion (23c) in which a plurality of terminals (26) electrically connected to the sensor element are disposed such that they extend in a direction intersecting the insertion direction of the sensor element.
    Type: Application
    Filed: July 27, 2012
    Publication date: March 28, 2013
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Kunihiko YONEZU, Hisaharu NISHIO, Norimasa Osawa, Tomohiro TAJIMA
  • Publication number: 20130036792
    Abstract: A gas sensor apparatus (1) includes a gas sensor (10) which outputs an output value corresponding to the concentration of a specific gas component contained in a gas; a pressure sensor (20) which measures the pressure of the gas; and a computation section (30) which computes a value representing the concentration of the specific gas component based on the output value from the gas sensor (10) and the pressure of the gas. The computation section (30) computes a concentration value using an expression derived from Fick's law and is a function of the output value and the pressure value, computes a correction value on the basis of a correction term which is a function of the provisional specific-component concentration and the pressure value, and corrects the provisional specific-component concentration using the correction value in order to compute the concentration value of the specific gas component.
    Type: Application
    Filed: August 7, 2012
    Publication date: February 14, 2013
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Masao TSUDUKI, Tomohiro Tajima, Ginjirou Ito
  • Publication number: 20120239271
    Abstract: A sensor control apparatus including a gas sensor having a sensor element, a housing and a base part formed of a resin. The apparatus includes a heating part and a control part. When the control part determines that a predetermined automatic stop condition has been satisfied, the control part switches from a control for maintaining the temperature of the sensor element at an activating temperature to a control in a stop state for reducing at least one of voltage and current supplied to the heating part so as to set a temperature of the base part to a value equal to or lower than a shape holding temperature of the resin. Also disclosed is a sensor control method for holding a temperature of a sensor element to an activating temperature.
    Type: Application
    Filed: March 14, 2012
    Publication date: September 20, 2012
    Applicant: NGK SPARK PLUG CO, LTD.
    Inventors: Tomohiro Tajima, Satoshi Ishikawa, Kunihiko Yonezu
  • Publication number: 20120055234
    Abstract: A gas sensor (200) includes a gas sensor element (10) extending in an axial direction (O), having a detection portion (11) provided at a front end thereof, and having electrode pads (12a) provided at a rear end thereof; connection terminals (31, 32) electrically connected to the respective electrode pads; and a cover (60, 61) covering the rear end of the gas sensor element and the connection terminals. The cover integrally has a connector portion (63) having an opening (63b) which allows an external connector to be inserted thereinto and removed therefrom in a predetermined direction, and has a connector terminal member (120) which can be inserted into the opening. The connector terminal member has a plurality of connector terminals (70) to be electrically connected to the respective connection terminals, and an insulator (121) integrally molded with the connector terminals. Also disclosed is a method for manufacturing the gas sensor.
    Type: Application
    Filed: September 1, 2011
    Publication date: March 8, 2012
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Kunihiko YONEZU, Hisaharu NISHIO, Takaya YOSHIKAWA, Tomohiro TAJIMA, Masao TSUZUKI
  • Publication number: 20120018305
    Abstract: A gas sensor (200) includes a gas sensor element (10) extending in the direction of an axis O, and a housing (50) made of metal, radially surrounding the gas sensor element, and adapted for inserting at least partially into a sensor-mounting hole (350) of a mounting body (300). The gas sensor (200) further includes a resin member (60, 61) which radially surrounds the housing at least partially and having a contact portion (C) in contact with the housing that is at least partially disposed axially frontward with respect to the outer surface of the mounting body (300) around the sensor-mounting hole, and a heat sink member (80) that is in contact with the housing at an axial position the same as or located frontward of the axial position of the front end of the contact portion.
    Type: Application
    Filed: July 21, 2011
    Publication date: January 26, 2012
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Takaya YOSHIKAWA, Tomohiro TAJIMA, Hisaharu NISHIO, Masao TSUZUKI, Kunihiko YONEZU
  • Publication number: 20110290015
    Abstract: A sensor control apparatus (3) includes a full-range gas sensor composed of an oxygen concentration detection cell having a pair of electrodes (21, 22) and an oxygen pump cell having a pair of electrodes (19, 20). In an electric circuit section (30), an Ip current flowing between the electrodes (19, 20) is controlled such that an electromotive force Vs produced between the electrodes (21, 22) becomes equal to a reference voltage. The reference voltage is usually set to a first reference voltage. However, when the subject gas is air, the reference voltage is set to a second reference voltage. Humidity of the subject gas is detected on the basis of an error ?Ip between an Ip current detected when the reference voltage is set to the first reference voltage, and an Ip current detected when the reference voltage is set to the second reference voltage.
    Type: Application
    Filed: April 19, 2010
    Publication date: December 1, 2011
    Applicant: NGK Spark Plug Co., Ltd.
    Inventors: Noboru Ishida, Kentaro Mori, Tomohiro Tajima
  • Publication number: 20110209523
    Abstract: A gas sensor (1) has an inner protector (120) and an outer protector (110); the inner protector (120) has an inner wall portion (160) having an inner gas inlet (170) for introducing gas to be measured into the interior of the inner protector (120); the outer protector (110) has an outer wall portion (130) having an outer gas inlet (140) for introducing the gas to be measured into the interior of the outer protector (110); a clearance of 1.35 mm or less is provided between the detection portion (11) and at least a portion of the inner wall portion (160); and when the gas sensor (1) is in use, the inner protector (120) is higher in temperature than the outer protector (110).
    Type: Application
    Filed: October 20, 2009
    Publication date: September 1, 2011
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Masanori Otsubo, Takaya Yoshikawa, Tomohiro Tajima, Masao Tsuzuki
  • Publication number: 20110174617
    Abstract: A gas sensor including a gas sensor element that extends in an axial direction and has a detection section at a front-end side thereof, and an electrode pad at a rear-end side thereof; a connection terminal that is electrically connected to the electrode pad; and an insulated separator that extends along the axial direction and has an inserting hole into which the connection terminal is inserted. An element side section is arranged within the inserting hole and is connected the electrode pad, and an external circuit side section extends further to the outside in a diametrical direction than an outer surface of the separator through one or more first bending sections from the element side section.
    Type: Application
    Filed: January 18, 2011
    Publication date: July 21, 2011
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Masao TSUZUKI, Tomohiro TAJIMA, Tomoki FUJII, Hisaharu NISHIO, Takaya YOSHIKAWA, Kunihiko YONEZU
  • Publication number: 20100313863
    Abstract: An intake system for an internal combustion engine includes an intake passage connected with an intake port of the internal combustion engine; an EGR passage merged with the intake passage at a junction portion; a gas sensor attached to the intake passage and configured to detect a concentration of specific gas; and a control section configured to control the internal combustion engine on the basis of an output signal of the gas sensor. A diameter-enlarged portion having an inner diameter larger than an inner diameter of the junction portion is formed at a portion of the intake passage which is located on a downstream side of the junction portion. The gas sensor is located downstream from the diameter-enlarged portion.
    Type: Application
    Filed: June 9, 2010
    Publication date: December 16, 2010
    Applicant: NGK SPARK PLUG CO., LTD.
    Inventors: Takaya YOSHIKAWA, Tomohiro TAJIMA, Masao Tsuzuki
  • Publication number: 20090200164
    Abstract: A gas sensor includes a plate-like sensor element having solid electrolyte layers; a circuit board having a processing circuit for processing an output signal from the sensor element; terminals connected to the sensor element and to the circuit board and serving as electric junctions therebetween; and a metallic casing which encloses the sensor element, the circuit board, and the terminals and has attachment portions for attachment to an external object. The attachment portions are attached to an inlet pipe at a position located downstream of an EGR gas inlet or to a cylinder head.
    Type: Application
    Filed: February 2, 2009
    Publication date: August 13, 2009
    Inventors: Takaya Yoshikawa, Masaru Kondo, Hiroshi Isomura, Hisaharu Nishio, Tomohiro Tajima