Patents by Inventor Kunihiro Iwatsuki

Kunihiro Iwatsuki 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: 10137774
    Abstract: Control device for a 4WD vehicle is provided. The 4WD vehicle includes a driving force source, main driving wheels, auxiliary driving wheels, a driving force transmission shaft, a first disconnection mechanism, and a second disconnection mechanism. The first disconnection mechanism and the second disconnection mechanism are engaged during 4WD traveling. One of the first disconnection mechanism and the second disconnection mechanism is a clutch. The control device includes an electronic control unit. The electronic control unit is configured to execute engagement control for controlling the engagement force of the clutch so that the driving force transmission shaft is maintained in a state prior to the initiation of a continuous increase in the rotation speed of the driving force transmission shaft.
    Type: Grant
    Filed: May 11, 2015
    Date of Patent: November 27, 2018
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Koji Takaira, Kunihiro Iwatsuki, Hiroyuki Ishii
  • Patent number: 9914456
    Abstract: A rotation state of each rotating element of a four-wheel drive vehicle and an operating state of each engagement element of a disconnect mechanism, corresponding to an operating state of the disconnect mechanism, are displayed on or near a vehicle model image on a vehicle display. Thus, it is possible to inform a driver of the operating state of the disconnect mechanism at any time. Thus, the driver is able to recognize the operating state of the disconnect mechanism at any time, so the driver is able to carry out driving based on the operating state.
    Type: Grant
    Filed: September 12, 2014
    Date of Patent: March 13, 2018
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Satoshi Shimizu, Yoshiro Obayashi, Ryota Horie, Norihiro Mizoguchi, Shintarou Mukougawa, Kunihiro Iwatsuki
  • Patent number: 9758037
    Abstract: Even in the case where it is difficult to increase an engine torque (Te) during switching when a running is switched to a 4WD running or a 2WD running during a 2WD_d running, an alternative control section suppresses a fluctuation in the driving force of a four-wheel drive vehicle, hence it is possible to suppress a switching shock and an unnatural feeling of deceleration occurring during the switching to the 4WD running or the 2WD running.
    Type: Grant
    Filed: August 29, 2014
    Date of Patent: September 12, 2017
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Kohei Horiike, Kunihiro Iwatsuki
  • Patent number: 9598068
    Abstract: In a control system, a transfer is connected to a rotation member between a driving power source and primary driving wheels and distributes dynamic power of the driving power source to secondary drive wheels. A driving power transmission shaft transmits the dynamic power of the driving power source distributed by the transfer to the secondary drive wheels. A connection-disconnection mechanism is disposed between the rotation member and the driving power transmission shaft. First and second clutches are disposed respectively between the driving power transmission shaft and right and left wheels of the secondary drive wheels. The electronic control unit is configured, when switching from a two-wheel-drive running state to a four-wheel-drive running state on the basis of a vehicle running state, to generate a transmission torque in the first clutch or the second clutch after controlling the connection-disconnection mechanism to engage the connection-disconnection mechanism.
    Type: Grant
    Filed: October 16, 2014
    Date of Patent: March 21, 2017
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yoshinori Maeda, Kunihiro Iwatsuki, Hiroyuki Ishii
  • Publication number: 20160229405
    Abstract: A rotation state of each rotating element of a four-wheel drive vehicle and an operating state of each engagement element of a disconnect mechanism, corresponding to an operating state of the disconnect mechanism, are displayed on or near a vehicle model image on a vehicle display. Thus, it is possible to inform a driver of the operating state of the disconnect mechanism at any time. Thus, the driver is able to recognize the operating state of the disconnect mechanism at any time, so the driver is able to carry out driving based on the operating state.
    Type: Application
    Filed: September 12, 2014
    Publication date: August 11, 2016
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Satoshi SHIMIZU, Yoshiro OBAYASHI, Ryota HORIE, Norihiro MIZOGUCHI, Shintarou MUKOUGAWA, Kunihiro IWATSUKI
  • Publication number: 20160193917
    Abstract: Even in the case where it is difficult to increase an engine torque (Te) during switching when a running is switched to a 4WD running or a 2WD running during a 2WD_d running, an alternative control section suppresses a fluctuation in the driving force of a four-wheel drive vehicle, hence it is possible to suppress a switching shock and an unnatural feeling of deceleration occurring during the switching to the 4WD running or the 2WD running.
    Type: Application
    Filed: August 29, 2014
    Publication date: July 7, 2016
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Kohei HORIIKE, Kunihiro IWATSUKI
  • Patent number: 9376015
    Abstract: A control apparatus for a 4WD vehicle is provided. The control apparatus includes a driving force source, main driving wheels, auxiliary driving wheels, a driving force transmission shaft, a first disconnection mechanism, a second disconnection mechanism, and an electronic control unit. The electronic control unit is configured to: (i) control one of the first disconnection mechanism and the second disconnection mechanism to be engaged and then engage the other one of the first disconnection mechanism and the second disconnection mechanism when a disconnect state is canceled; and (ii) set, when the disconnect state is canceled, an increasing gradient of a rotation speed of the driving force transmission shaft in accordance with a condition that the electronic control unit determines to cancel the disconnect state.
    Type: Grant
    Filed: May 11, 2015
    Date of Patent: June 28, 2016
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Koji Takaira, Kunihiro Iwatsuki, Hiroyuki Ishii
  • Publication number: 20160075342
    Abstract: A driving force indicator for a vehicle is provided. The vehicle includes a transmission. The driving force indicator includes a display and at least one electronic control unit. The electronic control unit is configured to control the display such that at least a driving force of a front wheel or rear wheel of the vehicle is indicated on the display. The electronic control unit is configured to change the driving force indicated on the display in synchronization with a change in driving force of the vehicle, a change in engine rotation speed or a change in rotation speed of a predetermined rotating member, caused by shift control over the transmission. The predetermined rotating member is a component of the transmission.
    Type: Application
    Filed: September 9, 2015
    Publication date: March 17, 2016
    Inventors: Satoshi Shimizu, Kunihiro Iwatsuki
  • Patent number: 9272700
    Abstract: A disconnect mechanism is configured to disconnect a predetermined rotating element from an engine and an auxiliary drive wheels while the vehicle is traveling in a two-wheel drive mode. The predetermined rotating element is configured to transmit power to the auxiliary drive wheels while the vehicle is traveling in a four-wheel drive mode. An electronic control unit is configured to: execute shift control when a shift condition of an automatic transmission is satisfied; selectively engage or release the disconnect mechanism based on a traveling state of the vehicle and a driver's predetermined operation; and control at least one of the automatic transmission or the disconnect mechanism such that a shift period based on the shift condition of the automatic transmission and an engagement-release period of the disconnect mechanism at least partially overlap with each other.
    Type: Grant
    Filed: November 13, 2014
    Date of Patent: March 1, 2016
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hideki Tamoto, Masayuki Arai, Yoshiro Obayashi, Kunihiro Iwatsuki
  • Publication number: 20150328983
    Abstract: A control apparatus for a 4WD vehicle is provided. The control apparatus includes a driving force source, main driving wheels, auxiliary driving wheels, a driving force transmission shaft, a first disconnection mechanism, a second disconnection mechanism, and an electronic control unit. The electronic control unit is configured to: (i) control one of the first disconnection mechanism and the second disconnection mechanism to be engaged and then engage the other one of the first disconnection mechanism and the second disconnection mechanism when a disconnect state is canceled; and (ii) set, when the disconnect state is canceled, an increasing gradient of a rotation speed of the driving force transmission shaft in accordance with a condition that the electronic control unit determines to cancel the disconnect state.
    Type: Application
    Filed: May 11, 2015
    Publication date: November 19, 2015
    Inventors: Koji Takaira, Kunihiro Iwatsuki, Hiroyuki Ishii
  • Publication number: 20150328982
    Abstract: Control device for a 4WD vehicle is provided. The 4WD vehicle includes a driving force source, main driving wheels, auxiliary driving wheels, a driving force transmission shaft, a first disconnection mechanism, and a second disconnection mechanism. The first disconnection mechanism and the second disconnection mechanism are engaged during 4WD traveling. One of the first disconnection mechanism and the second disconnection mechanism is a clutch. The control device includes an electronic control unit. The electronic control unit is configured to execute engagement control for controlling the engagement force of the clutch so that the driving force transmission shaft is maintained in a state prior to the initiation of a continuous increase in the rotation speed of the driving force transmission shaft.
    Type: Application
    Filed: May 11, 2015
    Publication date: November 19, 2015
    Inventors: Koji Takaira, Kunihiro Iwatsuki, Hiroyuki Ishii
  • Publication number: 20150142280
    Abstract: A disconnect mechanism is configured to disconnect a predetermined rotating element from an engine and an auxiliary drive wheels while the vehicle is traveling in a two-wheel drive mode. The predetermined rotating element is configured to transmit power to the auxiliary drive wheels while the vehicle is traveling in a four-wheel drive mode. An electronic control unit is configured to: execute shift control when a shift condition of an automatic transmission is satisfied; selectively engage or release the disconnect mechanism based on a traveling state of the vehicle and a driver's predetermined operation; and control at least one of the automatic transmission or the disconnect mechanism such that a shift period based on the shift condition of the automatic transmission and an engagement-release period of the disconnect mechanism at least partially overlap with each other.
    Type: Application
    Filed: November 13, 2014
    Publication date: May 21, 2015
    Inventors: Hideki Tamoto, Masayuki Arai, Yoshiro Obayashi, Kunihiro Iwatsuki
  • Publication number: 20150111696
    Abstract: In a control system, a transfer is connected to a rotation member between a driving power source and primary driving wheels and distributes dynamic power of the driving power source to secondary drive wheels. A driving power transmission shaft transmits the dynamic power of the driving power source distributed by the transfer to the secondary drive wheels. A connection-disconnection mechanism is disposed between the rotation member and the driving power transmission shaft. First and second clutches are disposed respectively between the driving power transmission shaft and right and left wheels of the secondary drive wheels. The electronic control unit is configured, when switching from a two-wheel-drive running state to a four-wheel-drive running state on the basis of a vehicle running state, to generate a transmission torque in the first clutch or the second clutch after controlling the connection-disconnection mechanism to engage the connection-disconnection mechanism.
    Type: Application
    Filed: October 16, 2014
    Publication date: April 23, 2015
    Inventors: Yoshinori Maeda, Kunihiro Iwatsuki, Hiroyuki Ishii
  • Patent number: 8160795
    Abstract: A drive power control apparatus for a vehicle includes a controller that adjusts the drive power for driving a vehicle to compensate for a parameter that affects the running state of the vehicle. When the vehicle enters a region where the acceleration of the vehicle needs to be changed based on the running environment or when the vehicle is traveling in the region in which the acceleration of the vehicle needs to be changed based on the running environment, the controller makes the amount by which the drive power is adjusted less than the amount by which the drive power is adjusted when the vehicle is traveling in a region other than the region in which the acceleration of the vehicle needs to be changed based on the running environment.
    Type: Grant
    Filed: April 26, 2007
    Date of Patent: April 17, 2012
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Kunihiro Iwatsuki, Shinya Iizuka
  • Patent number: 8075445
    Abstract: In a driving force control apparatus and a driving force control method, a curve ahead of a vehicle is detected; a target vehicle speed is set to pass the curve; a starting-point shift speed is set to pass the starting point of the curve; and an end-point shift speed is set to pass the end point of the curve. After a shift speed is changed to the starting-point shift speed, it is determined whether an additional engine brake is required at the starting-point shift speed. If it is determined that the engine brake is not required, the shift speed is changed to the end-point shift speed. Alternatively, if a vehicle speed is lower than or equal to a value corresponding to the target vehicle speed after the shift speed is changed to the starting-point shift speed, the shift speed is changed to the end-point shift speed.
    Type: Grant
    Filed: July 24, 2006
    Date of Patent: December 13, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Kazuyuki Shiiba, Kunihiro Iwatsuki, Shinya Iizuka
  • Patent number: 8002654
    Abstract: A control system for controlling a belt-type continuously variable transmission having a pulley capable of varying its groove width to which a belt is applied, in which the pulley is provided with an oil chamber to which the oil pressure is fed so that the pulley clamps the belt, in which the capacity of the oil chamber is varied in accordance with a change in the groove width, and in which the oil pressure in the oil chamber is controlled in accordance with a deviation between a target oil pressure and an actual oil pressure, comprising: a pressure-receiving capacity change detecting device for detecting a change in the capacity of the oil chamber; and an oil pressure control contents altering device for altering a degree to reflect the deviation on the oil pressure control of the oil chamber on the basis of a change in the capacity.
    Type: Grant
    Filed: February 7, 2005
    Date of Patent: August 23, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yasuhiro Oshiumi, Kunihiro Iwatsuki, Takayuki Amaya
  • Patent number: 7806790
    Abstract: A slippage detection system for a continuously variable transmission capable of continuously changing a ratio between a speed of rotation of an input member and a speed of rotation of an output member is provided. The slippage detection system calculates a correlation coefficient relating to the input rotation speed and the output rotation speed, based on a plurality of measurement values of the input rotation speed and a plurality of measurement values of the output rotation speed, and determines slippage of the torque transmitting member in the continuously variable transmission based on the calculated correlation coefficient.
    Type: Grant
    Filed: September 30, 2002
    Date of Patent: October 5, 2010
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Kunihiro Iwatsuki, Kazumi Hoshiya, Yasuhiro Oshiumi, Yasunori Nakawaki, Masataka Osawa, Hiroyuki Nishizawa, Hiroyuki Yamaguchi, Hideyuki Suzuki
  • Patent number: 7780570
    Abstract: An ECU executes a program for implementing a method that includes: a step of performing control so that torque capacity Tch of a frictional engagement device that is brought from an engaged state into a disengage state by a downshift operation is gradually reduced to start an inertia phase when a power-on downshift is performed; and a step of stopping the gradual reduction of the torque capacity Tch when the rate of change in an input shaft rotation speed NI of an automatic transmission has reached a desired rate of change ?N(1). Variation in output torque is kept small, and the shock that can occur at the time of a shift is thus reduced.
    Type: Grant
    Filed: November 19, 2007
    Date of Patent: August 24, 2010
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Kunihiro Iwatsuki, Takaaki Tokura
  • Publication number: 20100197455
    Abstract: A slippage detection system for a continuously variable transmission capable of continuously changing a gear ratio between an input rotation speed of an input member and an output rotation speed of an output member is provided. The slippage detection system calculate a sum of differences between an actual gear ratio calculated from measurement values of the input rotation speed and the output rotation speed and a target gear ratio over a predetermined period of time, and determines slippage in the continuously variable transmission based on the sum of differences.
    Type: Application
    Filed: April 16, 2010
    Publication date: August 5, 2010
    Applicant: Toyota Jidosha Kabushiki Kaisha
    Inventors: Kunihiro Iwatsuki, Kazumi Hoshiya, Yasuhiro Oshiumi, Yasunori Nakawaki, Hiroyuki Yamaguchi, Hiroyuki Nishizawa, Hideyuki Suzuki, Masataka Osawa
  • Publication number: 20100197454
    Abstract: A slippage detection system for a continuously variable transmission capable of continuously changing a gear ratio between an input rotation speed of an input member and an output rotation speed of an output member is provided. The slippage detection system compares a difference between an actual gear ratio calculated from measurement values of the input rotation speed and the output rotation speed and a target gear ratio with a predetermined reference value, and determines slippage in the continuously variable transmission when the difference exceeds the reference value at least a predetermined number of times in a predetermined period of time.
    Type: Application
    Filed: April 16, 2010
    Publication date: August 5, 2010
    Applicant: Toyota Jidosha Kabushiki Kaisha
    Inventors: Kunihiro IWATSUKI, Kazumi Hoshiya, Yasuhiro Oshiumi, Yasunori Nakawaki, Hiroyuki Yamaguchi, Hiroyuki Nishizawa, Hideyuki Suzuki, Masataka Osawa