Patents by Inventor Tatsuhiro Tokunaga

Tatsuhiro Tokunaga 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).

  • Publication number: 20210231077
    Abstract: An engine apparatus includes an ignition control section and an injection control section. When the partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of an expansion stroke to initiate the SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes the injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. Energy of the preceding ignition is set to be lower when a swirl flow is gentle than when the swirl flow is intense.
    Type: Application
    Filed: April 23, 2019
    Publication date: July 29, 2021
    Inventors: Kota MATSUMOTO, Tomonori URUSHIHARA, Keiji MARUYAMA, Masanari SUEOKA, Ryohei ONO, Yuji HARADA, Toru MIYAMOTO, Atsushi INOUE, Tatsuhiro TOKUNAGA, Takuya OHURA, Yusuke KAWAI, Tomohiro NISHIDA, Keita ARAI, Yodai YAMAGUCHI
  • Publication number: 20210222610
    Abstract: The invention is provided with an ignition control section and an injection control section. When partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of an expansion stroke to initiate SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes an injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. Timing of the preceding ignition is set to be more retarded when an engine speed is high than when the engine speed is low.
    Type: Application
    Filed: April 17, 2019
    Publication date: July 22, 2021
    Inventors: Kota MATSUMOTO, Tomonori URUSHIHARA, Keiji MARUYAMA, Masanari SUEOKA, Ryohei ONO, Yuji HARADA, Toru MIYAMOTO, Atsushi INOUE, Tatsuhiro TOKUNAGA, Takuya OHURA, Yusuke KAWAI, Tomohiro NISHIDA, Keita ARAI, Yodai YAMAGUCHI
  • Publication number: 20210222642
    Abstract: An engine control apparatus includes an ignition control section and an injection control section. When the partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of a expansion stroke to initiate the SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes the injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. The energy of the preceding ignition is set to be higher when fuel concentration specified by a fuel concentration specification section is low than when the fuel concentration is high.
    Type: Application
    Filed: April 23, 2019
    Publication date: July 22, 2021
    Inventors: Kota MATSUMOTO, Tomonori URUSHIHARA, Keiji MARUYAMA, Masanari SUEOKA, Ryohei ONO, Yuji HARADA, Toru MIYAMOTO, Atsushi INOUE, Tatsuhiro TOKUNAGA, Takuya OHURA, Yusuke KAWAI, Tomohiro NISHIDA, Keita ARAI, Yodai YAMAGUCHI
  • Publication number: 20210189945
    Abstract: The invention is provided with an ignition control section and an injection control section. When partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of an expansion stroke to initiate SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes an injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. Ignition timing of the preceding ignition is set to be more retarded when fuel concentration specified by a fuel concentration specification section is low than when the fuel concentration is high.
    Type: Application
    Filed: April 17, 2019
    Publication date: June 24, 2021
    Inventors: Kota MATSUMOTO, Tomonori URUSHIHARA, Keiji MARUYAMA, Masanari SUEOKA, Ryohei ONO, Yuji HARADA, Toru MIYAMOTO, Atsushi INOUE, Tatsuhiro TOKUNAGA, Takuya OHURA, Yusuke KAWAI, Tomohiro NISHIDA, Keita ARAI, Yodai YAMAGUCHI
  • Patent number: 11008970
    Abstract: A control device for controlling an engine provided with a fuel pump including a pressurizing chamber, a plunger inserted into the pressurizing chamber and which changes a volume of the pressurizing chamber, and an on-off valve configured to open and close a suction port, is provided. When a pressurizing cycle consists of a period of pressurizing stroke in which the volume of the pressurizing chamber is reduced to allow fuel to be pressurized and a period of suction stroke in which the volume of the pressurizing chamber is increased to allow fuel to be drawn into the pressurizing chamber, a closing cycle of the on-off valve is controlled so that a ratio of the closing cycle to the pressurizing cycle becomes smaller in a second combustion mode where a partial compression-ignition combustion is performed than in a first combustion mode where SI combustion is performed.
    Type: Grant
    Filed: July 7, 2020
    Date of Patent: May 18, 2021
    Assignee: Mazda Motor Corporation
    Inventors: Masami Nishida, Toru Miyamae, Shigeki Yamashita, Kazuhiro Takemoto, Michio Ito, Kazuhiro Nishimura, Yusuke Kawai, Tetsuya Chikada, Tatsuhiro Tokunaga
  • Patent number: 10995681
    Abstract: A combustion control device for an engine includes a plurality of cylinders, a surge tank disposed in an intake path to the cylinders, an independent intake passage connecting the surge tank and an intake port of each of the cylinders, a fuel injection valve that is disposed for each of the cylinders and that supplies fuel into each of the cylinders, and a control unit that controls a fuel injection amount of each of the fuel injection valves according to an engine operating state. The control unit corrects a target fuel injection amount of each of the cylinders, the target fuel injection amount being determined according to the engine operating state, based on a re-intake correction amount set in each of the cylinders according to a re-intake amount of intake air from the intake port in internal EGR in each of the cylinders.
    Type: Grant
    Filed: March 4, 2020
    Date of Patent: May 4, 2021
    Assignee: Mazda Motor Corporation
    Inventors: Masanari Sueoka, Junichi Taga, Hideki Omori, Keiji Maruyama, Tatsuhiro Tokunaga, Takuya Ohura, Toru Miyamoto, Tomohiro Nishida, Kenji Tanimura, Shinji Takayama, Yusuke Kawai, Atsushi Inoue
  • Publication number: 20210115839
    Abstract: An engine control apparatus includes an ignition control section and an injection control section. When partial compression ignition combustion is carried out, the ignition control section causes an ignition plug to carry out: main ignition in which a spark is generated in a late period of a compression stroke or an initial period of an expansion stroke to initiate the SI combustion; and preceding ignition in which the spark is generated at earlier timing than the main ignition. Also, when the partial compression ignition combustion is carried out, the injection control section causes the injector to inject fuel at such timing that the fuel exists in a cylinder at an earlier time point than the preceding ignition. Energy of the preceding ignition is set to be higher when an engine speed is high than when the engine speed is low.
    Type: Application
    Filed: April 23, 2019
    Publication date: April 22, 2021
    Inventors: Kota MATSUMOTO, Tomonori URUSHIHARA, Keiji MARUYAMA, Masanari SUEOKA, Ryohei ONO, Yuji HARADA, Toru MIYAMOTO, Atsushi INOUE, Tatsuhiro TOKUNAGA, Takuya OHURA, Yusuke KAWAI, Tomohiro NISHIDA, Keita ARAI, Yodai YAMAGUCHI
  • Patent number: 10927749
    Abstract: A control device for an engine is provided, which includes a combustion controlling module, and an ignition retard determining module configured to determine whether there is a request for an ignition retard for retarding an ignition timing of an ignition plug. When the controlling module controls the ignition plug and an injector so that the SPCCI combustion is performed and there is not the ignition retard request, the controlling module executes a control in which the entire fuel to be injected in one cycle is injected in an intake stroke and a jump-spark ignition is carried out at a basic ignition timing, and when there is the ignition retard request, the controlling module executes a control in which an injection is performed in an intake stroke, a portion of the entire fuel is injected in a compression stroke, and the ignition timing is retarded from the basic ignition timing.
    Type: Grant
    Filed: December 16, 2019
    Date of Patent: February 23, 2021
    Assignee: Mazda Motor Corporation
    Inventors: Tatsuhiro Tokunaga, Masanari Sueoka, Keiji Maruyama, Tomohiro Nishida, Takuya Ohura, Toru Miyamoto, Junichi Taga, Hideki Omori, Kenji Tanimura, Hiroyuki Yabe
  • Patent number: 10920655
    Abstract: A control device is provided for an engine in which SPCCI combustion is carried out in which SI combustion of a portion of a mixture gas is performed by jump-spark ignition, and CI combustion of the remaining mixture gas is performed by self-ignition. When the engine is low load and a temperature is less than a given value, an early injection in which fuel is injected during an intake stroke and a retarded injection in which fuel is injected during the second half of a compression stroke are performed, and SPCCI combustion of A/F-lean mixture gas is performed. When the engine is low load and the temperature is greater than or equal to the given value, an injection amount ratio of the early injection is increased and the ratio of the retarded injection is decreased, and SPCCI combustion of A/F-lean mixture gas is performed.
    Type: Grant
    Filed: January 29, 2020
    Date of Patent: February 16, 2021
    Assignee: Mazda Motor Corporation
    Inventors: Keiji Maruyama, Takuya Ohura, Masanari Sueoka, Tatsuhiro Tokunaga, Toru Miyamoto, Tomohiro Nishida
  • Patent number: 10914259
    Abstract: A control device is provided for an engine in which premixed compression ignition combustion is carried out. The device includes an air amount adjusting mechanism, a variable valve mechanism, an exhaust choke valve, a water temperature sensor, and a processor. The processor controls the variable valve mechanism so that a valve overlap period of a given amount or more is formed in a low-load range where the engine load is low, and controls an injector, the air amount adjusting mechanism, and the exhaust choke valve so that A/F lean mixture gas is formed inside a combustion chamber, and premixed compression ignition combustion of the mixture gas is carried out. During the operation in the low-load range, the combustion controlling module makes an opening of the exhaust choke valve when a temperature parameter is low, smaller than that when the temperature parameter is high.
    Type: Grant
    Filed: January 29, 2020
    Date of Patent: February 9, 2021
    Assignee: Mazda Motor Corporation
    Inventors: Keiji Maruyama, Takuya Ohura, Masanari Sueoka, Tatsuhiro Tokunaga, Toru Miyamoto, Tomohiro Nishida
  • Publication number: 20210017929
    Abstract: A control device for controlling an engine provided with a fuel pump including a pressurizing chamber, a plunger inserted into the pressurizing chamber and which changes a volume of the pressurizing chamber, and an on-off valve configured to open and close a suction port, is provided. When a pressurizing cycle consists of a period of pressurizing stroke in which the volume of the pressurizing chamber is reduced to allow fuel to be pressurized and a period of suction stroke in which the volume of the pressurizing chamber is increased to allow fuel to be drawn into the pressurizing chamber, a closing cycle of the on-off valve is controlled so that a ratio of the closing cycle to the pressurizing cycle becomes smaller in a second combustion mode where a partial compression-ignition combustion is performed than in a first combustion mode where SI combustion is performed.
    Type: Application
    Filed: July 7, 2020
    Publication date: January 21, 2021
    Inventors: Masami Nishida, Toru Miyamae, Shigeki Yamashita, Kazuhiro Takemoto, Michio Ito, Kazuhiro Nishimura, Yusuke Kawai, Tetsuya Chikada, Tatsuhiro Tokunaga
  • Patent number: 10837377
    Abstract: A method of implementing control logic of a compression ignition engine is provided. The engine includes an injector, a variable valve operating mechanism, an ignition plug, at least one sensor, and a processor. The processor outputs the signal to the ignition plug in a specific operating state so that unburnt mixture gas combusts by self ignition after the ignition plug ignites the mixture gas inside a combustion chamber. The method includes determining a geometric compression ratio ? of the engine, and determining control logic defining a valve opening angle CA of an intake valve. The valve opening angle CA (deg) is determined so that the following expression is satisfied, if the geometric compression ratio ? is ?<14, ?40?+800+D?CA?60??550+D. Here, D is a correction term according to the engine speed NE (rpm), D=3.3×10?10NE3?1.0×10?6NE2+7.0×10?4NE.
    Type: Grant
    Filed: May 14, 2019
    Date of Patent: November 17, 2020
    Assignee: Mazda Motor Corporation
    Inventors: Masanari Sueoka, Atsushi Inoue, Keiji Maruyama, Takuya Ohura, Tomohiro Nishida, Yusuke Kawai, Tetsuya Chikada, Tatsuhiro Tokunaga
  • Publication number: 20200332735
    Abstract: A control device is provided for an engine in which premixed compression ignition combustion is carried out. The device includes an air amount adjusting mechanism, a variable valve mechanism, an exhaust choke valve, a water temperature sensor, and a processor. The processor controls the variable valve mechanism so that a valve overlap period of a given amount or more is formed in a low-load range where the engine load is low, and controls an injector, the air amount adjusting mechanism, and the exhaust choke valve so that A/F lean mixture gas is formed inside a combustion chamber, and premixed compression ignition combustion of the mixture gas is carried out. During the operation in the low-load range, the combustion controlling module makes an opening of the exhaust choke valve when a temperature parameter is low, smaller than that when the temperature parameter is high.
    Type: Application
    Filed: January 29, 2020
    Publication date: October 22, 2020
    Inventors: Keiji Maruyama, Takuya Ohura, Masanari Sueoka, Tatsuhiro Tokunaga, Toru Miyamoto, Tomohiro Nishida
  • Publication number: 20200332704
    Abstract: A control device is provided for an engine in which SPCCI combustion is carried out in which SI combustion of a portion of a mixture gas is performed by jump-spark ignition, and CI combustion of the remaining mixture gas is performed by self-ignition. When the engine is low load and a temperature is less than a given value, an early injection in which fuel is injected during an intake stroke and a retarded injection in which fuel is injected during the second half of a compression stroke are performed, and SPCCI combustion of A/F-lean mixture gas is performed. When the engine is low load and the temperature is greater than or equal to the given value, an injection amount ratio of the early injection is increased and the ratio of the retarded injection is decreased, and SPCCI combustion of A/F-lean mixture gas is performed.
    Type: Application
    Filed: January 29, 2020
    Publication date: October 22, 2020
    Inventors: Keiji Maruyama, Takuya Ohura, Masanari Sueoka, Tatsuhiro Tokunaga, Toru Miyamoto, Tomohiro Nishida
  • Publication number: 20200318555
    Abstract: A combustion control device for an engine includes a plurality of cylinders, a surge tank disposed in an intake path to the cylinders, an independent intake passage connecting the surge tank and an intake port of each of the cylinders, a fuel injection valve that is disposed for each of the cylinders and that supplies fuel into each of the cylinders, and a control unit that controls a fuel injection amount of each of the fuel injection valves according to an engine operating state. The control unit corrects a target fuel injection amount of each of the cylinders, the target fuel injection amount being determined according to the engine operating state, based on a re-intake correction amount set in each of the cylinders according to a re-intake amount of intake air from the intake port in internal EGR in each of the cylinders.
    Type: Application
    Filed: March 4, 2020
    Publication date: October 8, 2020
    Inventors: Masanari SUEOKA, Junichi TAGA, Hideki OMORI, Keiji MARUYAMA, Tatsuhiro TOKUNAGA, Takuya OHURA, Toru MIYAMOTO, Tomohiro NISHIDA, Kenji TANIMURA, Shinji TAKAYAMA, Yusuke KAWAI, Atsushi INOUE
  • Publication number: 20200318572
    Abstract: The control apparatus for a compression ignition type engine includes a plurality of cylinder inner pressure sensors that detect pressure in each cylinder, and a combustion control unit. The combustion control unit corrects a target fuel injection amount of each cylinder by an injector based on a deviation between a predicted combustion period that is a period from an ignition timing by an ignition plug to a predetermined mass combustion timing and that is obtained based on a preset combustion model, and an actual combustion period that is a period from the ignition timing by the ignition plug to an actual combustion timing and that is obtained based on cylinder inner pressure, such that the period from the ignition timing by the ignition plug to the predetermined mass combustion timing, which is the timing when fuel having a predetermined mass ratio combusts, is equalized in each cylinder.
    Type: Application
    Filed: March 4, 2020
    Publication date: October 8, 2020
    Inventors: Masanari SUEOKA, Junichi TAGA, Hideki OMORI, Keiji MARUYAMA, Tatsuhiro TOKUNAGA, Takuya OHURA, Toru MIYAMOTO, Tomohiro NISHIDA, Kenji TANIMURA, Shinji TAKAYAMA
  • Patent number: 10794323
    Abstract: A compression-ignition engine control system is provided, which includes an intake phase-variable mechanism and a controller. The controller controls the intake phase-variable mechanism to form a gas-fuel ratio (G/F) lean environment in which burnt gas remains inside a cylinder and an air-fuel ratio is near a stoichiometric air-fuel ratio, and controls the spark plug to spark-ignite the mixture gas to combust in a partial compression-ignition combustion. The controller controls the intake phase-variable mechanism to retard, as an engine speed increases at a constant engine load, an intake valve close timing on a retarding side of BDC of intake stroke and an intake valve open timing on an advancing side of TDC of exhaust stroke, and controls the intake phase-variable mechanism so that a change rate in the intake valve open timing according to the engine speed becomes larger in a high engine speed range.
    Type: Grant
    Filed: May 15, 2019
    Date of Patent: October 6, 2020
    Assignee: Mazda Motor Corporation
    Inventors: Atsushi Inoue, Masanari Sueoka, Keiji Maruyama, Takuya Ohura, Tomohiro Nishida, Yusuke Kawai, Tetsuya Chikada, Tatsuhiro Tokunaga
  • Patent number: 10767577
    Abstract: A method of implementing control logic of a compression-ignition engine is provided. A controller outputs a signal to a injector and a variable valve operating mechanism so that a gas-fuel ratio (G/F) becomes leaner than a stoichiometric air fuel ratio, and an air-fuel ratio (A/F) becomes equal to or richer than the stoichiometric air fuel ratio, and to an ignition plug so that unburnt mixture gas combusts by self-ignition after the ignition plug ignites mixture gas inside a combustion chamber. The method includes steps of determining a geometric compression ratio and determining the control logic defining an intake valve close timing IVC. IVC (deg.aBDC) is determined so that the following expression is satisfied: if the geometric compression ratio ? is 10??<17, 0.4234?2?22.926?+207.84+C?IVC??0.4234?2+22.926??167.84+C where C is a correction term according to an engine speed NE (rpm), C=3.3×10?10NE3?1.0×10?6NE2+7.0×10?4NE.
    Type: Grant
    Filed: May 13, 2019
    Date of Patent: September 8, 2020
    Assignee: Mazda Motor Corporation
    Inventors: Masanari Sueoka, Atsushi Inoue, Keiji Maruyama, Takuya Ohura, Tomohiro Nishida, Yusuke Kawai, Tetsuya Chikada, Masatoshi Hidaka, Toshiaki Takahashi, Tatsuhiro Tokunaga
  • Patent number: 10767593
    Abstract: A compression-ignition engine control system is provided, which includes an intake variable mechanism and a controller. Within a first operating range and a second operating range on a higher engine load side, the controller controls the variable mechanism to form a gas-fuel ratio (G/F) lean environment in which an air-fuel ratio inside a cylinder is near a stoichiometric air-fuel ratio and burnt gas remains inside the cylinder, and controls a spark plug to spark-ignite mixture gas inside the cylinder to combust in a partial compression-ignition combustion. The controller controls the variable mechanism to advance the intake valve open timing on an advancing side of a TDC of the exhaust stroke, as the engine load increases within the first range, and retard the intake valve open timing on the advancing side of the TDC of the exhaust stroke, as the engine load increases within the second range.
    Type: Grant
    Filed: May 14, 2019
    Date of Patent: September 8, 2020
    Assignee: Mazda Motor Corporation
    Inventors: Atsushi Inoue, Masanari Sueoka, Keiji Maruyama, Takuya Ohura, Tomohiro Nishida, Yusuke Kawai, Tetsuya Chikada, Tatsuhiro Tokunaga
  • Patent number: 10760519
    Abstract: A method of implementing control logic of a compression-ignition engine is provided. A control part of the engine performs a calculation according to the control logic corresponding to an engine operating state in response to a measurement of a measurement part, controls a fuel injection part, a variable valve operating mechanism, an ignition part and a supercharger so that a G/F becomes leaner than a stoichiometric air fuel ratio and a A/F becomes equal to or richer than the stoichiometric air fuel ratio, while causing the supercharger to boost, and controls the ignition part so that unburnt mixture gas combusts by self-ignition after the ignition. The method includes determining a supercharging pressure P, and determining control logic defining a close timing IVC of an intake valve. When determining the control logic, the close timing IVC (deg.aBDC) is determined so that the supercharging pressure P (kPa) satisfies the following expression: P?8.0×10?11IVC6?1.0×10?8IVC5+3.0×10?7IVC4?4.0×10?6IVC3+0.
    Type: Grant
    Filed: May 13, 2019
    Date of Patent: September 1, 2020
    Assignee: Mazda Motor Corporation
    Inventors: Masanari Sueoka, Atsushi Inoue, Keiji Maruyama, Takuya Ohura, Tomohiro Nishida, Yusuke Kawai, Tetsuya Chikada, Tatsuhiro Tokunaga