Patents by Inventor Akio Maekawa

Akio Maekawa 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: 6945909
    Abstract: A torque distribution control device for a four-wheel drive vehicle having a torque distribution device for distributing the drive power transmitted from an engine to either of the front wheels or the rear wheels as prime drive wheels, to other wheels as sub-drive wheels determines a pre-torque in a feed forward sense based on the vehicle speed, the throttle opening degree and the gear shift step of a transmission. A compensation torque is determined in a feedback sense based on the vehicle speed and the rotational speed difference between the drive wheels and the sub-drive wheels. A torque transmission clutch is controlled based on a command torque which is obtained by the addition of the pre-torque and the compensation torque, so that the command torque is distributed to the sub-drive wheels.
    Type: Grant
    Filed: October 30, 2003
    Date of Patent: September 20, 2005
    Assignee: Toyoda Koki Kabushiki Kaisha
    Inventor: Akio Maekawa
  • Patent number: 6886652
    Abstract: A torque distribution control device for a four-wheel drive vehicle is disclosed, wherein a torque transmitted from an engine to prime drive wheels is distributed by an electromagnetic clutch to sub-drive wheels on an on-demand basis. A pre-torque is determined based on a vehicle speed and a throttle opening degree in a feed-forward sense. A compensation torque is determined based on the rotational speed difference between the prime drive wheels and the sub-drive wheels and the vehicle speed in a feedback sense. The pre-torque and the compensation torque are added for a command torque, depending on which the electromagnetic clutch is controlled to transmit the torque from the engine to the sub-drive wheels.
    Type: Grant
    Filed: January 20, 2004
    Date of Patent: May 3, 2005
    Assignee: Toyoda Koki Kabushiki Kaisha
    Inventors: Akio Maekawa, Yasushi Yamada
  • Patent number: 6873896
    Abstract: A drive-force distribution controller controls a drive-force transmission apparatus of a vehicle in order to control transmission of drive force to rear wheels or front wheels of the vehicle in accordance with a designated drive-force transmission ratio. The drive-force transmission ratio is changed on the basis of vehicle speed, differential rotational speed (speed difference between the front and rear wheels), and throttle opening. Alternatively, the drive-force transmission ratio is changed on the basis of vehicle speed, throttle opening, and throttle open speed. The change speed of current which is supplied to the drive-force transmission apparatus in order to control the drive-force transmission ratio is adjusted in accordance with a command current filter value which is determined on the basis of vehicle speed and a command current filter map of a vehicle-speed responsive type.
    Type: Grant
    Filed: April 24, 2003
    Date of Patent: March 29, 2005
    Assignee: Toyoda Koki Kabushiki Kaisha
    Inventors: Akio Maekawa, Ryohei Shigeta
  • Publication number: 20040168846
    Abstract: A torque distribution control device for a four-wheel drive vehicle is disclosed, wherein a torque transmitted from an engine to prime drive wheels is distributed by an electromagnetic clutch to sub-drive wheels on an on-demand basis. A pre-torque is determined based on a vehicle speed and a throttle opening degree in a feed-forward sense. A compensation torque is determined based on the rotational speed difference between the prime drive wheels and the sub-drive wheels and the vehicle speed in a feedback sense. The pre-torque and the compensation torque are added for a command torque, depending on which the electromagnetic clutch is controlled to transmit the torque from the engine to the sub-drive wheels.
    Type: Application
    Filed: January 20, 2004
    Publication date: September 2, 2004
    Applicant: TOYODA KOKI KABUSHIKI KAISHA
    Inventors: Akio Maekawa, Yasushi Yamada
  • Publication number: 20040092363
    Abstract: A torque distribution control device for a four-wheel drive vehicle is disclosed having a torque distribution device for distributing the drive power transmitted from an engine to either of the front wheels or the rear wheels as prime drive wheels, to other wheels as sub-drive wheels. In the control device, a pre-torque is determined in a feed forward sense based on the vehicle speed, the throttle opening degree and the gear shift step of a transmission. A compensation torque is determined in a feedback sense based on the vehicle speed and the rotational speed difference between the drive wheels and the sub-drive wheels. A torque transmission clutch is controlled based on a command torque which is obtained by the addition of the pre-torque and th compensation torque, so that the command torque is distributed to the sub-drive wheels. In the control device of another embodiment, a pre-torque is determined in a feed forward sense based on the vehicle speed and the throttle opening degree.
    Type: Application
    Filed: October 30, 2003
    Publication date: May 13, 2004
    Applicant: TOYODA KOKI KABUSHIKI KAISHA
    Inventor: Akio Maekawa
  • Publication number: 20030201131
    Abstract: A drive-force distribution controller controls a drive-force transmission apparatus of a vehicle in order to control transmission of drive force to rear wheels or front wheels of the vehicle in accordance with a designated drive-force transmission ratio. The drive-force transmission ratio is changed on the basis of vehicle speed, differential rotational speed (speed difference between the front and rear wheels), and throttle opening. Alternatively, the drive-force transmission ratio is changed on the basis of vehicle speed, throttle opening, and throttle open speed. The change speed of current which is supplied to the drive-force transmission apparatus in order to control the drive-force transmission ratio is adjusted in accordance with a command current filter value which is determined on the basis of vehicle speed and a command current filter map of a vehicle-speed responsive type.
    Type: Application
    Filed: April 24, 2003
    Publication date: October 30, 2003
    Applicant: TOYODA KOKI KABUSHIKI KAISHA
    Inventors: Akio Maekawa, Ryohei Shigeta
  • Publication number: 20030091528
    Abstract: A transparent liquid composition comprising water, an oil-soluble ingredient and a surfactant; more specifically, a transparent liquid composition comprises 50 wt % or more of water, 30 wt % or lower of an oil-soluble ingredient and a 20 wt % or lower of a surfactant wherein the content of the surfactant is less than that of the oil-soluble ingredient.
    Type: Application
    Filed: October 23, 2002
    Publication date: May 15, 2003
    Inventors: Masashi Goto, Akio Maekawa