Patents by Inventor Seiko Tamada

Seiko Tamada 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: 8205584
    Abstract: A brushless motor of a variable valve mechanism varies a actuation parameter of an intake valve of an engine. A position sensor outputs a pulse signal when the brushless motor rotates. A position counter calculates a counter value by counting edges of the pulse signal. A motor control device obtains a detection value of a motor rotational angle based on the counter value when the motor control device is in a powered state. An engine control device determines that the detection value of the motor rotational angle is displaced from the actual value when the engine control device detects that the engine is operating and the motor control device portion is in a non-powered state.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: June 26, 2012
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Minoru Noda, Naohide Fuwa, Seiko Tamada
  • Patent number: 8060291
    Abstract: After power supply from a backup power source to a volatile memory is restored from temporary suspension, a remaining data determining section determines whether data of change history remaining in the volatile memory is data that has been stored immediately before the suspension of the power supply. When it is determined that the data remaining in the volatile memory is not the data that has been stored immediately before suspension of the power supply, a reference value learning section moves an actuator to a limit position, assigns the reference value to an initial value, and clears the change history. When suspension of the power supply from the backup power source reoccurs before completion of the reference value learning by the reference value learning section, a control section invalidates the determination of the remaining data determining section and performs the reference value learning, after the power supply is restored.
    Type: Grant
    Filed: April 14, 2008
    Date of Patent: November 15, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Naohide Fuwa, Seiko Tamada, Keisuke Ohnishi
  • Patent number: 8050850
    Abstract: An internal combustion engine includes a valve timing change mechanism that changes the phase of an intake cam, and a lift amount change mechanism that changes lift amount by causing displacement of a control shaft. An electronic control unit performs a coordinated control in which the lift amount change mechanism is operated such that the position of the control shaft that is detected by a position detection sensor becomes the target position, and the valve timing change mechanism is operated according to a control state of the lift amount change mechanism. When a discrepancy between the actual position of the control shaft and the detected position thereof is estimated to be large, coordinated control is forbidden and the valve timing change mechanism is operated based on engine load.
    Type: Grant
    Filed: May 26, 2008
    Date of Patent: November 1, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Naohide Fuwa, Tokiji Ito, Seiko Tamada, Hiroyuki Kanemoto
  • Publication number: 20100175662
    Abstract: An electronic control unit (60) performs maximum position learning by driving an actuator (50) to move a control shaft (340), and learning the position where stopping occurs because the cylinder head (20) contacts with the Hi end stopper (343) as the movable limit position (Hi end) where the maximum lift amount of the intake valve is largest, to correct the cumulative movement of the control shaft (340). The electronic control unit (60) prevents maximum position learning when the engine speed NE is higher Than a prescribed rotational speed NEst.
    Type: Application
    Filed: May 23, 2008
    Publication date: July 15, 2010
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Naohide Fuwa, Seiko Tamada, Hiroyuki Kanemoto
  • Publication number: 20100170459
    Abstract: An internal combustion engine includes a valve timing change mechanism that changes the phase of an intake cam, and a lift amount change mechanism that changes lift amount by causing displacement of a control shaft. An electronic control unit performs a coordinated control in which the lift amount change mechanism is operated such that the position of the control shaft that is detected by a position detection sensor becomes the target position, and the valve timing change mechanism is operated according to a control state of the lift amount change mechanism. When a discrepancy between the actual position of the control shaft and the detected position thereof is estimated to be large, coordinated control is forbidden and the valve timing change mechanism is operated based on engine load.
    Type: Application
    Filed: May 26, 2008
    Publication date: July 8, 2010
    Applicant: Toyota Jidosha Kabushiki Kaisha
    Inventors: Naohide Fuwa, Tokiji Ito, Seiko Tamada, Hiroyuki Kanemoto
  • Publication number: 20100088007
    Abstract: After power supply from a backup power source to a volatile memory is restored from temporary suspension, a remaining data determining section determines whether data of change history remaining in the volatile memory is data that has been stored immediately before the suspension of the power supply. When it is determined that the data remaining in the volatile memory is not the data that has been stored immediately before suspension of the power supply, a reference value learning section moves an actuator to a limit position, assigns the reference value to an initial value, and clears the change history. When suspension of the power supply from the backup power source reoccurs before completion of the reference value learning by the reference value learning section, a control section invalidates the determination of the remaining data determining section and performs the reference value learning, after the power supply is restored.
    Type: Application
    Filed: April 14, 2008
    Publication date: April 8, 2010
    Applicant: Toyota Jidosha Kabushiki Kaisha
    Inventors: Naohide Fuwa, Seiko Tamada, Keisuke Ohnishi
  • Publication number: 20100071644
    Abstract: A brushless motor of a variable valve mechanism varies a actuation parameter of an intake valve of an engine. A position sensor outputs a pulse signal when the brushless motor rotates. A position counter calculates a counter value by counting edges of the pulse signal. A motor control device obtains a detection value of a motor rotational angle based on the counter value when the motor control device is in a powered state. An engine control device determines that the detection value of the motor rotational angle is displaced from the actual value when the engine control device detects that the engine is operating and the motor control device portion is in a non-powered state.
    Type: Application
    Filed: December 26, 2007
    Publication date: March 25, 2010
    Applicant: Toyota Jidosha Kabushiki Kaisha
    Inventors: Minoru Noda, Naohide Fuwa, Seiko Tamada