Patents by Inventor Makoto Miwa

Makoto Miwa 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: 20100161203
    Abstract: When a driving region of an engine is in a specified self-ignited combustion region, a valve timing is controlled in such a manner as to establish a negative valve overlap period in which an exhaust valve and an intake valve are closed. During the negative valve overlap period, a direct injection is performed to reform a fuel. After the direct injection, a port injection is performed to control an output. Thereby, a self-ignited combustion control is performed. During the self-ignited combustion control, a fuel reform degree of the fuel injected by the direct fuel injection is detected, and a self-ignited combustion condition in a present combustion cycle is estimated based on the fuel reform degree detected in the present combustion cycle. A fuel injection quantity of the intake port fuel injection is corrected according to the estimated self-ignited combustion condition in order to stabilize the self-ignited combustion condition.
    Type: Application
    Filed: December 23, 2009
    Publication date: June 24, 2010
    Applicant: DENSO CORPORATION
    Inventors: Masahiro Shigenaga, Kimitaka Saitoh, Masatoshi Basaki, Kiyohiko Watanabe, Makoto Miwa
  • Publication number: 20090151425
    Abstract: A NOx sensor diagnostic device for an internal combustion engine includes a NOx sensor disposed in the exhaust passage of the engine, through which exhaust air discharged from the engine flows, and configured to detect nitrogen oxide included in the exhaust air, an air supply device for supplying air to the exhaust passage, and a sensor determination device for making the NOx sensor detect nitrogen oxide in the exhaust passage, to which air is supplied by the air supply device while the engine is stopped, and for determining that the NOx sensor is abnormal when an output value of the NOx sensor is equal to or larger than a predetermined reference value.
    Type: Application
    Filed: December 11, 2008
    Publication date: June 18, 2009
    Applicant: DENSO CORPORATION
    Inventor: Makoto MIWA
  • Publication number: 20090139212
    Abstract: The ECU performs an on-board diagnosis for a NOx sensor. The diagnosis is carried out when an exhaust system of an engine is fully cooled after shut-down of the engine. The diagnosis is carried out after a temperature in the exhaust passage is lowered to an ambient temperature. In the diagnosis proceeding, the ECU activates a heater attached on the NOx sensor. The ECU detects a heating performance of the heater and determines whether the heating performance is sufficient or not. The NOx sensor is in a stable condition after the engine system is fully cooled. Therefore, it is possible to perform the diagnosis while eliminating or suppressing influences of operating conditions of the engine system and a residual heat in the exhaust system.
    Type: Application
    Filed: November 25, 2008
    Publication date: June 4, 2009
    Applicant: DENSO CORPORATION
    Inventor: Makoto Miwa
  • Patent number: 7460947
    Abstract: A control unit uses upper and lower limit guard values to limit a power generation quantity of a power generator and thereby to maintain the current combustion mode during power generation of the power generator. The control unit computes a remaining electric charge of a battery. When the remaining electric charge drops to a predetermined value or below, the control unit cancels a combustion mode maintaining operation, which maintains the current combustion mode, is cancelled, so that priority is given to the power generation of the power generator to recover the remaining electric charge of the battery. Also, when an electric power consumption in a vehicle is equal to or greater than a predetermined value, the combustion mode maintaining operation is cancelled, and the power generation quantity of the power generator is controlled in a manner that does not cause overdischarge of the battery.
    Type: Grant
    Filed: August 8, 2006
    Date of Patent: December 2, 2008
    Assignee: DENSO CORPORATION
    Inventors: Yukihiro Yamashita, Makoto Miwa, Daiji Isobe
  • Patent number: 7291935
    Abstract: A generator control device controls a generator that is driven by an engine to charge a battery and supply electric power to electric loads. In the generator control device the following steps are carried out: calculating a required electric power; calculating a difference rate that is a difference in an amount of a hazardous gas component of engine exhaust gas between a first case in which the generator generates the required electric power and a second case in which the generator does not generate an electric power divided by the electric power and controlling the generator to generate the required electric power if the difference is equal to or smaller than a first reference value.
    Type: Grant
    Filed: June 2, 2006
    Date of Patent: November 6, 2007
    Assignee: Denso Corporation
    Inventors: Yukihiro Yamashita, Makoto Miwa, Daiji Isobe
  • Publication number: 20070029800
    Abstract: A control unit uses upper and lower limit guard values to limit a power generation quantity of a power generator and thereby to maintain the current combustion mode during power generation of the power generator. The control unit computes a remaining electric charge of a battery. When the remaining electric charge drops to a predetermined value or below, the control unit cancels a combustion mode maintaining operation, which maintains the current combustion mode, is cancelled, so that priority is given to the power generation of the power generator to recover the remaining electric charge of the battery. Also, when an electric power consumption in a vehicle is equal to or greater than a predetermined value, the combustion mode maintaining operation is cancelled, and the power generation quantity of the power generator is controlled in a manner that does not cause overdischarge of the battery.
    Type: Application
    Filed: August 8, 2006
    Publication date: February 8, 2007
    Applicant: DENSO CORPORATION
    Inventors: Yukihiro Yamashita, Makoto Miwa, Daiji Isobe
  • Publication number: 20060273591
    Abstract: A generator control device controls a generator that is driven by an engine to charge a battery and supply electric power to electric loads. In the generator control device the following steps are carried out: calculating a required electric power; calculating a difference rate that is a difference in an amount of a hazardous gas component of engine exhaust gas between a first case in which the generator generates the required electric power and a second case in which the generator does not generate an electric power divided by the electric power and controlling the generator to generate the required electric power if the difference is equal to or smaller than a first reference value.
    Type: Application
    Filed: June 2, 2006
    Publication date: December 7, 2006
    Applicant: DENSO CORPORATION
    Inventors: Yukihiro Yamashita, Makoto Miwa, Daiji Isobe
  • Publication number: 20060182126
    Abstract: Mobile nodes communicate with each other to transfer packets between a source and a destination using a multi-hop network strategy for communicating packets in the forward direction and using a mobile infostation network strategy, alone or in combination with a multi-hop network strategy, for communicating packets in the reverse direction, thereby exploiting a controlled flooding communication scheme that balances the tradeoffs between capacity improvement and random packet delay. The system may be used in a variety of applications, including an intelligent highway information system.
    Type: Application
    Filed: February 15, 2005
    Publication date: August 17, 2006
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Wing Yuen, King Huang, Norihiro Kondo, Makoto Miwa
  • Patent number: 6892712
    Abstract: A leak check system executes a leak check processing. In the leak check processing, the system closes a canister valve and a purge valve to close the fuel vapor purge system. Then, the system detects and monitors a pressure in the fuel vapor purge system. During the leak check processing, the system detects a rapid change of the pressure that is caused by a deformation of a wall of a fuel tank. The system cancels or suspends the processing to avoid erroneous detection of the leak. If the leak check is canceled, the system opens the canister valve to open the fuel vapor purge system.
    Type: Grant
    Filed: August 30, 2002
    Date of Patent: May 17, 2005
    Assignee: DENSO Corporation
    Inventors: Makoto Miwa, Syujiro Morinaga, Yoshinori Maegawa, Keiji Wakahara
  • Publication number: 20050039525
    Abstract: A fuel-vapor-processing system for an engine has a canister for accumulating fuel evaporation gas. The system has a leak-check apparatus for checking a leak on passages. The leak-check apparatus includes a leak-check means for carrying out leak-check processing when the engine if in a stopped state. The leak-check means operates only if a predetermined condition is satisfied. It is thus possible to reduce the number of times the leak-check processing is carried out and, hence, possible to reduce power consumption. For example, only if a relatively small leak is detected when the engine is in a running state, the leak-check processing is carried out in a stopped state to verify existence of such a leak. In the leak-check processing, the temperature of fuel, detected by a sensor or an estimated value, may be taken into consideration.
    Type: Application
    Filed: September 16, 2004
    Publication date: February 24, 2005
    Applicant: DENSO CORPORATION
    Inventors: Keiji Wakahara, Syujiro Morinaga, Yoshinori Maegawa, Makoto Miwa
  • Patent number: 6854452
    Abstract: In a fuel vapor handling system of this invention, an ECU performs a leak check to check a leak of fuel vapor in a fuel vapor passage when the engine is at a stop. The ECU functions to detect the quantity of fuel during the engine stop. The ECU detects the quantity of fuel at the time of engine starting. Furthermore, the ECU compares the quantity of fuel measured at the time of engine starting with the quantity of fuel measured at the preceding engine stop, to thereby determine whether a filler cap was opened during the engine stop. When the filler cap was opened during the engine stop, a result of the leak check will be cancelled. When the filler cap was not opened, the result of the leak check will be determined.
    Type: Grant
    Filed: October 18, 2002
    Date of Patent: February 15, 2005
    Assignee: Denso Corporation
    Inventors: Syujiro Morinaga, Yoshinori Maegawa, Keiji Wakahara, Makoto Miwa
  • Patent number: 6832509
    Abstract: A fuel vapor control system has a controller that carries out a leak check processing after the engine is stopped. The controller includes a device that intermittently activates the controller itself or a part of the controller to sample an internal pressure of the fuel vapor passage. Then, after a predetermined time, the controller determines that whether the sampled values of the internal pressure indicate a leak or not by evaluating the sampled values. According to the arrangement, since at least a part of the controller is activated intermittently, the consumption of electricity can be reduced. The fuel vapor control system has a canister valve and a purge valve made of normally close type valves in order to reduce the consumption of electricity after the engine is stopped.
    Type: Grant
    Filed: September 4, 2002
    Date of Patent: December 21, 2004
    Assignee: Denso Corporation
    Inventors: Syujiro Morinaga, Yoshinori Maegawa, Keiji Wakahara, Makoto Miwa
  • Patent number: 6807851
    Abstract: A fuel-vapor-processing system for an engine has a canister for accumulating fuel evaporation gas. The system has a leak-check apparatus for checking a leak on passages. The leak-check apparatus includes a leak-check means for carrying out leak-check processing when the engine if in a stopped state. The leak-check means operates only if a predetermined condition is satisfied. It is thus possible to reduce the number of times the leak-check processing is carried out and, hence, possible to reduce power consumption. For example, only if a relatively small leak is detected when the engine is in a running state, the leak-check processing is carried out in a stopped state to verify existence of such a leak. In the leak-check processing, the temperature of fuel, detected by a sensor or an estimated value, may be taken into consideration.
    Type: Grant
    Filed: July 25, 2002
    Date of Patent: October 26, 2004
    Assignee: Denso Corporation
    Inventors: Keiji Wakahara, Syujiro Morinaga, Yoshinori Maegawa, Makoto Miwa
  • Publication number: 20030150417
    Abstract: An automatic engine start and stop system for vehicles automatically stops and then starts an engine of a vehicle when predetermined automatic stop condition and start condition are satisfied, respectively. The system determines whether a fuel tank is being refueled after the engine is automatically stopped. If the refueling is detected, the engine is prohibited from being automatically started even if the predetermined automatic start condition is satisfied.
    Type: Application
    Filed: February 3, 2003
    Publication date: August 14, 2003
    Applicant: DENSO CORPORATION
    Inventor: Makoto Miwa
  • Publication number: 20030075156
    Abstract: In a fuel vapor handling system of this invention, an ECU performs a leak check to check a leak of fuel vapor in a fuel vapor passage when the engine is at a stop. The ECU functions to detect the quantity of fuel during the engine stop. The ECU detects the quantity of fuel at the time of engine starting. Furthermore, the ECU compares the quantity of fuel measured at the time of engine starting with the quantity of fuel measured at the preceding engine stop, to thereby determine whether a filler cap was opened during the engine stop. When the filler cap was opened during the engine stop, a result of the leak check will be cancelled. When the filler cap was not opened, the result of the leak check will be determined.
    Type: Application
    Filed: October 18, 2002
    Publication date: April 24, 2003
    Inventors: Syujiro Morinaga, Yoshinori Maegawa, Keiji Wakahara, Makoto Miwa
  • Publication number: 20030056573
    Abstract: A leak check system executes a leak check processing. In the leak check processing, the system closes a canister valve and a purge valve to close the fuel vapor purge system. Then, the system detects and monitors a pressure in the fuel vapor purge system. During the leak check processing, the system detects a rapid change of the pressure that is caused by a deformation of a wall of a fuel tank. The system cancels or suspends the processing to avoid erroneous detection of the leak. If the leak check is canceled, the system opens the canister valve to open the fuel vapor purge system.
    Type: Application
    Filed: August 30, 2002
    Publication date: March 27, 2003
    Inventors: Makoto Miwa, Syujiro Morinaga, Yoshinori Maegawa, Keiji Wakahara
  • Publication number: 20030051540
    Abstract: A fuel vapor control system has a controller that carries out a leak check processing after the engine is stopped. The controller includes a device that intermittently activates the controller itself or a part of the controller to sample an internal pressure of the fuel vapor passage. Then, after a predetermined time, the controller determines that whether the sampled values of the internal pressure indicate a leak or not by evaluating the sampled values. According to the arrangement, since at least a part of the controller is activated intermittently, the consumption of electricity can be reduced. The fuel vapor control system has a canister valve and a purge valve made of normally close type valves in order to reduce the consumption of electricity after the engine is stopped.
    Type: Application
    Filed: September 4, 2002
    Publication date: March 20, 2003
    Inventors: Syujiro Morinaga, Yoshinori Maegawa, Keiji Wakahara, Makoto Miwa
  • Publication number: 20030019286
    Abstract: A fuel-vapor-processing system for an engine has a canister for accumulating fuel evaporation gas. The system has a leak-check apparatus for checking a leak on passages. The leak-check apparatus includes a leak-check means for carrying out leak-check processing when the engine if in a stopped state. The leak-check means operates only if a predetermined condition is satisfied. It is thus possible to reduce the number of times the leak-check processing is carried out and, hence, possible to reduce power consumption. For example, only if a relatively small leak is detected when the engine is in a running state, the leak-check processing is carried out in a stopped state to verify existence of such a leak. In the leak-check processing, the temperature of fuel, detected by a sensor or an estimated value, may be taken into consideration.
    Type: Application
    Filed: July 25, 2002
    Publication date: January 30, 2003
    Inventors: Keiji Wakahara, Syujiro Morinaga, Yoshinori Maegawa, Makoto Miwa
  • Patent number: RE41660
    Abstract: A fuel vapor control system has a controller that carries out a leak check processing after the engine is stopped. The controller includes a device that intermittently activates the controller itself or a part of the controller to sample an internal pressure of the fuel vapor passage. Then, after a predetermined time, the controller determines that whether the sampled values of the internal pressure indicate a leak or not by evaluating the sampled values. According to the arrangement, since at least a part of the controller is activated intermittently, the consumption of electricity can be reduced. The fuel vapor control system has a canister valve and a purge valve made of normally close type valves in order to reduce the consumption of electricity after the engine is stopped.
    Type: Grant
    Filed: December 20, 2006
    Date of Patent: September 14, 2010
    Assignee: Denso Corporation
    Inventors: Syujiro Morinaga, Yoshinori Maegawa, Keiji Wakahara, Makoto Miwa
  • Patent number: RE41823
    Abstract: A leak check system executes a leak check processing. In the leak check processing, the system closes a canister valve and a purge valve to close the fuel vapor purge system. Then, the system detects and monitors a pressure in the fuel vapor purge system. During the leak check processing, the system detects a rapid change of the pressure that is caused by a deformation of a wall of a fuel tank. The system cancels or suspends the processing to avoid erroneous detection of the leak. If the leak check is canceled, the system opens the canister valve to open the fuel vapor purge system.
    Type: Grant
    Filed: May 17, 2007
    Date of Patent: October 19, 2010
    Assignee: DENSO Corporation
    Inventors: Makoto Miwa, Syujiro Morinaga, Yoshinori Maegawa, Keiji Wakahara