Patents by Inventor Yasuki Tamura

Yasuki Tamura 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: 8015799
    Abstract: There is provided a multicylinder internal combustion engine. Branches of an exhaust manifold are connected to a common exhaust gas sensor via respective exhaust communication passages. The exhaust gas sensor detects the exhaust air-fuel ratio of each cylinder. The distance from exhaust ports of the engine to the exhaust gas sensor is set to be shorter than the distance from the exhaust ports to a catalyst disposed in an exhaust pipe.
    Type: Grant
    Filed: July 1, 2005
    Date of Patent: September 13, 2011
    Assignees: Mitsubishi Jidosha Kogyo Kabushiki Kaisha, Mitsubishi Jidosha Kogyo K.K.
    Inventors: Yasuki Tamura, Kazuhito Kawashima
  • Patent number: 7275364
    Abstract: The air/fuel ratio of exhaust flowing into a catalytic converter is forcibly modulated, between a lean air/fuel ratio leaner than a target average air/fuel ratio and a rich air/fuel ratio richer than the target average air/fuel ratio, with a specific period, a specific amplitude, a specific modulation ratio and a specific waveform. During the forcible modulation (S10, S12), the ratio of a time for which the output of an oxygen sensor is greater than a standard value Sb for the output set between the maximum and minimum values of the output (“rich” output time), or of a time for which it is smaller than the standard value Sb (“lean” output time), in a predetermined period of time, or a value correlating with this ratio is obtained (S14), and the air/fuel ratio of the exhaust is controlled on the basis of this ratio or the value correlating with this ratio (S16, S18).
    Type: Grant
    Filed: October 17, 2003
    Date of Patent: October 2, 2007
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventors: Yasuki Tamura, Kazuhito Kawashima, Hitoshi Toda
  • Patent number: 7275367
    Abstract: There is provided an exhaust pressure-adjusting valve that is brought into a closed position due to a biasing force of a resilient body and is opened against the biasing force of the resilient body due to the exhaust pressure in an exhaust channel, which is raised in response to the closing of a throttle valve, in which valve-opening area is increased or decreased according to the displacement of the resilient body, to thereby adjust the exhaust pressure. The exhaust pressure-adjusting valve has a unit for changing the growth rate of the valve-opening area, which gradually heightens the growth rate of the valve-opening area with respect to the displacement of the resilient body in a valve-opening direction.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: October 2, 2007
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventors: Yasuki Tamura, Motoyuki Suzuki
  • Patent number: 7216479
    Abstract: Normally, at the time of cold-start of an internal combustion engine or the like, the flow of exhaust in an exhaust passage of the internal combustion engine is suppressed or two-stage combustion is carried out so as to promote exhaust purification in an exhaust system. However, when a correlation value of a braking force required to be generated by a vacuum type brake booster is greater than a correlation value of a braking force that can be actually generated by the vacuum type brake booster, a restricting device restricts the suppression of the exhaust flow or a two-stage combustion prohibiting device prohibits the two-combustion.
    Type: Grant
    Filed: January 17, 2003
    Date of Patent: May 15, 2007
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventor: Yasuki Tamura
  • Publication number: 20070000482
    Abstract: The air/fuel ratio of exhaust flowing into a catalytic converter is forcibly modulated, between a lean air/fuel ratio leaner than a target average air/fuel ratio and a rich air/fuel ratio richer than the target average air/fuel ratio, with a specific period, a specific amplitude, a specific modulation ratio and a specific waveform. During the forcible modulation (S10, S12), the ratio of a time for which the output of an oxygen sensor is greater than a standard value Sb for the output set between the maximum and minimum values of the output (“rich” output time), or of a time for which it is smaller than the standard value Sb (“lean” output time), in a predetermined period of time, or a value correlating with this ratio is obtained (S14), and the air/fuel ratio of the exhaust is controlled on the basis of this ratio or the value correlating with this ratio (S16, S18).
    Type: Application
    Filed: October 17, 2003
    Publication date: January 4, 2007
    Applicant: Mitsubishi Jidosha Kogyo Kabushii Kaisha
    Inventors: Yasuki Tamura, Kazuhito Kawashima, Hitoshi Toda
  • Patent number: 7051689
    Abstract: There is provided a failure diagnostic system which includes an intake channel and an exhaust channel in communication with cylinders of an internal combustion engine; the exhaust pressure increasing device that increases the exhaust system pressure of the exhaust channel; an intake system pressure detecting device provided in the intake channel, for detecting the intake system pressure; and an exhaust pressure increase failure diagnostic section that determines whether the exhaust pressure increasing device has failed or not according to intake system pressure information obtained by the intake system pressure detecting device and a predetermined failure diagnosis reference range.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: May 30, 2006
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventors: Yasuki Tamura, Kazuhito Kawashima, Hitoshi Toda
  • Patent number: 7003945
    Abstract: An exhaust emission control device for internal combustion engine comprising air-fuel ratio modulating means and air-fuel ratio modulation adjusting means. The air-fuel ratio modulation adjusting means adjusts a lean period to be longer or the degree of leaning to be higher, during which the air-fuel ratio of exhaust gas is a lean air-fuel ratio, compared with when an oxygen storage (S10) of a three-way catalyst exceeds a first given value X1 if the oxygen storage is not higher than the first given value X1 (S16, S18), and adjusts a rich period to be longer or the degree of enriching to be higher, during which the exhaust air-fuel ratio is a rich air-fuel ratio, compared with when a reducing agent storage (S12) exceeds a second given value Y1 if the reducing agent storage is not higher than the second given value Y1 (S20, S22).
    Type: Grant
    Filed: June 17, 2004
    Date of Patent: February 28, 2006
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventor: Yasuki Tamura
  • Publication number: 20060000204
    Abstract: There is provided a multicylinder internal combustion engine. Branches of an exhaust manifold are connected to a common exhaust gas sensor via respective exhaust communication passages. The exhaust gas sensor detects the exhaust air-fuel ratio of each cylinder. The distance from exhaust ports of the engine to the exhaust gas sensor is set to be shorter than the distance from the exhaust ports to a catalyst disposed in an exhaust pipe.
    Type: Application
    Filed: July 1, 2005
    Publication date: January 5, 2006
    Inventors: Yasuki Tamura, Kazuhito Kawashima
  • Patent number: 6976356
    Abstract: When a NOx-releasing unit is operated to change an air-fuel ratio to a rich side to thereby establish a low-oxygen-concentration atmosphere of an exhaust gas such that NOx is released from a NOx catalyst, a reducer-supplying unit additionally supplies a reducer during an operating period of the NOx-releasing unit for reducing NOx released into an exhaust path such that release of NOx balances with reduction of NOx, thereby reducing NOx released from the NOx catalyst and thus suppressing worsening of an exhaust gas performance.
    Type: Grant
    Filed: February 2, 2004
    Date of Patent: December 20, 2005
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventors: Kojiro Okada, Osamu Nakayama, Yasuki Tamura, Kazuhito Kawashima
  • Patent number: 6968677
    Abstract: There is provided an exhaust emission control apparatus for an internal combustion engine, which includes a failure diagnostic device that fixes three parameters selected from the group consisting of the engine speed detected by an engine speed detecting device, the fuel quantity controlled by a fuel quantity control device, the ignition timing controlled by an ignition timing control device, and the intake air volume controlled by an intake air control device at respective predetermined values, and finds values of the remaining one parameter, and compares the values of the remaining one parameter with each other to determine whether an exhaust flow control apparatus has failed or not.
    Type: Grant
    Filed: March 14, 2003
    Date of Patent: November 29, 2005
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventor: Yasuki Tamura
  • Patent number: 6938613
    Abstract: An internal combustion engine is comprised of a gas injecting device injecting gas into the combustion chamber of the internal combustion engine, and a gas injection control device controlling the gas injecting device, wherein the gas injection control device provides control such that the gas is injected toward the combustion chamber for a period of time after flame extinguishing timing and before exhaust valve closing timing. Therefore, the internal combustion engine is capable of reliably combusting HC, CO, smoke, and so forth remained in a combustion chamber due to a quenching phenomenon or the like.
    Type: Grant
    Filed: March 27, 2003
    Date of Patent: September 6, 2005
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventors: Yasuki Tamura, Kazuhito Kawashima, Kazuhide Iwasa
  • Publication number: 20050172614
    Abstract: A three-way catalyst (30) comprises a microporous catalyst element (30a) having a micropore group whose average pore opening size is smaller than molecular size of HC in a washcoat and a macroporous catalyst element (30b) having a macropore group whose average pore opening size is larger than the molecular size of HC in a washcoat.
    Type: Application
    Filed: January 6, 2005
    Publication date: August 11, 2005
    Applicants: Mitsubishi Jidosha Kogyo Kabushiki Kaisha, ICT CO., LTD., INTERNATIONAL CATALYST TECHNOLOGY, INC.
    Inventors: Yasuki Tamura, Keisuke Tashiro, Akihisa Okumura
  • Patent number: 6920752
    Abstract: An exhaust emission control device of an internal-combustion engine comprises a three-way catalytic converter provided in an exhaust passage of the internal-combustion engine, and an air-fuel ratio varying element for forcedly varying an air-fuel ratio of exhaust flowing into the three-way catalytic converter, between a rich air-fuel ratio and a lean air-fuel ratio. A variation characteristic altering element for altering a characteristic of the air-fuel ratio variation is provided, and the three-way catalytic converter has a HC selective oxidizing component for selectively oxidizing HC rather than CO, and a CO storage component for storing CO in a reducing atmosphere. The variation characteristic altering element alters a characteristic of the air-fuel variation (such as an A/F variation period) depending on an stored CO quantity correlative value (such as a quantity of flowing-in CO) which correlates with a quantity of CO stored by the CO storage component (S12).
    Type: Grant
    Filed: September 4, 2003
    Date of Patent: July 26, 2005
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventor: Yasuki Tamura
  • Publication number: 20050138923
    Abstract: There is provided an exhaust pressure-adjusting valve that is brought into a closed position due to a biasing force of a resilient body and is opened against the biasing force of the resilient body due to the exhaust pressure in an exhaust channel, which is raised in response to the closing of a throttle valve, in which valve-opening area is increased or decreased according to the displacement of the resilient body, to thereby adjust the exhaust pressure. The exhaust pressure-adjusting valve has means for changing the growth rate of the valve-opening area, which gradually heightens the growth rate of the valve-opening area with respect to the displacement of the resilient body in a valve-opening direction.
    Type: Application
    Filed: December 22, 2004
    Publication date: June 30, 2005
    Inventors: Yasuki Tamura, Motoyuki Suzuki
  • Patent number: 6892527
    Abstract: A catalyst deterioration suppressing apparatus and method stops supply of fuel when an engine is decelerating, and prohibits the supply of fuel from being stopped when the catalyst temperature is equal to or higher than a predetermined temperature when the engine is decelerating. When the supply of fuel is prohibted from being stopped, the air-fuel ratio is prohibited from being feedback-controlled. As a result, it is possible to control the air-fuel ratio in a stable manner while suppressing deterioration of a catalyst.
    Type: Grant
    Filed: July 16, 2003
    Date of Patent: May 17, 2005
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventors: Katsunori Ueda, Masaaki Kaneko, Kojiro Okada, Ishido Masanori, Yasuki Tamura
  • Patent number: 6892528
    Abstract: A catalyst deterioration detecting apparatus aims at accurately determining whether or not a catalyst deteriorates even if a strict standard for catalyst deterioration is established. The catalyst deterioration detecting apparatus includes catalyst temperature sensing means for obtaining temperature of a catalyst, including ceria (CeO2) serving as an oxygen storage agent, and deterioration detecting means for detecting a degree of deterioration of the catalyst if the temperature is obtained by the catalyst temperature sensing means is equal to or higher than an activation temperature at which the catalyst is activated and is in a particular temperature range causing NOX conversion efficiency of the catalyst to decrease.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: May 17, 2005
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventors: Kojiro Okada, Yasuki Tamura, Kinichi Iwachido, Osamu Nakayama
  • Patent number: 6840035
    Abstract: An exhaust emission control system for an internal combustion engine includes an exhaust air-fuel ratio changing device switching the exhaust air-fuel ratio of exhaust gas flowing into one of an upstream exhaust passages and the exhaust air-fuel ratio of exhaust gas flowing into the other one of the upstream exhaust passages to a rich air-fuel ratio and to a lean air-fuel ratio alternately on a predetermined cycle longer than each of combustion cycles of the internal combustion engine, to thereby determine whether upstream catalytic converters have deteriorated or not according to a change in the exhaust air-fuel ratio outputted by upstream exhaust sensors provided downstream of the upstream catalytic converters. Therefore, it is possible to surely determine whether catalytic converters have deteriorated even slightly or not while ensuring a high exhaust emission control performance.
    Type: Grant
    Filed: February 27, 2003
    Date of Patent: January 11, 2005
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventor: Yasuki Tamura
  • Publication number: 20040255574
    Abstract: An exhaust emission control device for internal combustion engine comprising air-fuel ratio modulating means and air-fuel ratio modulation adjusting means. The air-fuel ratio modulation adjusting means adjusts a lean period to be longer or the degree of leaning to be higher, during which the air-fuel ratio of exhaust gas is a lean air-fuel ratio, compared with when an oxygen storage (S10) of a three-way catalyst exceeds a first given value X1 if the oxygen storage is not higher than the first given value X1 (S16, S18), and adjusts a rich period to be longer or the degree of enriching to be higher, during which the exhaust air-fuel ratio is a rich air-fuel ratio, compared with when a reducing agent storage (S12) exceeds a second given value Y1 if the reducing agent storage is not higher than the second given value Y1 (S20, S22).
    Type: Application
    Filed: June 17, 2004
    Publication date: December 23, 2004
    Inventor: Yasuki Tamura
  • Publication number: 20040244473
    Abstract: There is provided a failure diagnostic system which includes an intake channel and an exhaust channel in communication with cylinders of an internal combustion engine; the exhaust pressure increasing device that increases the exhaust system pressure of the exhaust channel; an intake system pressure detecting device provided in the intake channel, for detecting the intake system pressure; and an exhaust pressure increase failure diagnostic section that determines whether the exhaust pressure increasing device has failed or not according to intake system pressure information obtained by the intake system pressure detecting device and a predetermined failure diagnosis reference range.
    Type: Application
    Filed: March 25, 2004
    Publication date: December 9, 2004
    Inventors: Yasuki Tamura, Kazuhito Kawashima, Hitoshi Toda
  • Patent number: 6817172
    Abstract: An exhaust purifying apparatus includes an exhaust throttle valve provided in an exhaust passage of the internal combustion engine for closing the exhaust passage to increase a pressure therein; a relief passage provided bypassing the exhaust throttle valve; a relief valve provided to be able to close the relief passage and to be open when receiving an increased pressure in the exhaust passage with closure of the exhaust throttle valve; fuel cut determining means for determining whether the engine is during fuel cut-off; and a relief-valve forcibly operating means for closing the exhaust throttle valve when the fuel cut determining means determines that the engine is during fuel cut-off, thereby removing condensed water accumulated in the relief passage to avoid faulty operations of the relief valve, and suppressing deteriorated fuel consumption upon operation of the relief valve.
    Type: Grant
    Filed: June 24, 2003
    Date of Patent: November 16, 2004
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventor: Yasuki Tamura