Patents by Inventor Yuji Takatsuka

Yuji Takatsuka 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: 7539567
    Abstract: An electric power steering control includes a torque sensor for detecting steering torque as torque information, a motor for generating assist torque, a calculation section for calculating a motor current command value based on the torque information at each predetermined sampling period, and a motor current control section for driving and controlling the motor based on the motor current command value. The calculation section includes a first target current calculation section for calculating a first target current based on the torque information detected in a time series manner at a first control period corresponding to the sampling period, and a second target current calculation section for calculating a second target current based on the first target current at a second control period shorter than the first control period. The motor current control section controls the motor by using the second target current as the motor current command value.
    Type: Grant
    Filed: March 17, 2006
    Date of Patent: May 26, 2009
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yuji Takatsuka
  • Publication number: 20070073462
    Abstract: An electric power steering control includes a torque sensor for detecting steering torque as torque information, a motor for generating assist torque, a calculation section for calculating a motor current command value based on the torque information at each predetermined sampling period, and a motor current control section for driving and controlling the motor based on the motor current command value. The calculation section includes a first target current calculation section for calculating a first target current based on the torque information detected in a time series manner at a first control period corresponding to the sampling period, and a second target current calculation section for calculating a second target current based on the first target current at a second control period shorter than the first control period. The motor current control section controls the motor by using the second target current as the motor current command value.
    Type: Application
    Filed: March 17, 2006
    Publication date: March 29, 2007
    Inventor: Yuji Takatsuka
  • Patent number: 6902028
    Abstract: Conventionally, there was a problem that in cases when it is difficult to place a temperature sensor in the vicinity of a heat-generating portion, overheating could not be prevented.
    Type: Grant
    Filed: June 10, 2004
    Date of Patent: June 7, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yuji Takatsuka, Katsuhiko Ohmae, Norihiro Yamaguchi, Susumu Zeniya, Takayuki Kifuku, Shigeki Ohtagaki
  • Patent number: 6860361
    Abstract: Conventionally, there was a problem that in cases when it is difficult to place a temperature sensor in the vicinity of a heat-generating portion, overheating could not be prevented.
    Type: Grant
    Filed: August 6, 2003
    Date of Patent: March 1, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yuji Takatsuka, Katsuhiko Ohmae, Norihiro Yamaguchi, Susumu Zeniya, Takayuki Kifuku, Shigeki Ohtagaki
  • Publication number: 20040222037
    Abstract: Conventionally, there was a problem that in cases when it is difficult to place a temperature sensor in the vicinity of a heat-generating portion, overheating could not be prevented.
    Type: Application
    Filed: June 10, 2004
    Publication date: November 11, 2004
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Yuji Takatsuka, Katsuhiko Ohmae, Norihiro Yamaguchi, Susumu Zeniya, Takayuki Kifuku, Shigeki Ohtagaki
  • Publication number: 20040026161
    Abstract: Conventionally, there was a problem that in cases when it is difficult to place a temperature sensor in the vicinity of a heat-generating portion, overheating could not be prevented.
    Type: Application
    Filed: August 6, 2003
    Publication date: February 12, 2004
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Yuji Takatsuka, Katsuhiko Ohmae, Norihiro Yamaguchi, Susumu Zeniya, Takayuki Kifuku, Shigeki Ohtagaki
  • Patent number: 6497303
    Abstract: An electric power steering system is proposed in which it is possible to inspect function of switches connected to a motor. An electric power steering system having a CPU 2 for calculating a control amount for controlling a motor 3 corresponding to a steering torque 1 and a driving circuit 8 for driving the motor 3, comprises a first switch 12 connected in series with the motor 3, a voltage monitoring circuit 10 for monitoring motor voltage, and a drive restricting circuit 11 for restricting operation of the driving circuit 8 besides the CPU 2, and in which the CPU 2 inspects function of the first switch 12 from drive of the driving circuit 8 and results detected by the voltage monitoring circuit 10 when it is judged that the driving circuit 8 is not restricted from a situation of the steering torque 1 or the drive inhibiting circuit 11.
    Type: Grant
    Filed: October 17, 2000
    Date of Patent: December 24, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiroshi Nishimura, Shigeki Ohtagaki, Kazuo Kikuta, Yuji Takatsuka
  • Publication number: 20020179363
    Abstract: Conventionally, there was a problem that in cases when it is difficult to place a temperature sensor in the vicinity of a heat-generating portion, overheating could not be prevented.
    Type: Application
    Filed: November 29, 2001
    Publication date: December 5, 2002
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Yuji Takatsuka, Katsuhiko Ohmae, Norihiro Yamaguchi, Susumu Zeniya, Takayuki Kifuku, Shigeki Ohtagaki
  • Patent number: 6070692
    Abstract: An electric power steering control system in which the steering "feel" is improved, having a steering force detector an electric motor for producing an auxiliary steering force, a motor current detector and a control unit for deciding the motor current value and rotational direction at least in accordance with the detected steering force. The motor current is limited in accordance with the detected steering force and motor current values.
    Type: Grant
    Filed: September 15, 1999
    Date of Patent: June 6, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Yuji Takatsuka, Shun-Ichi Wada
  • Patent number: 6054827
    Abstract: A current flowing to a motor 8 for generating a steering assist force for a steering mechanism is detected by a motor current detecting circuit 24 to be inputted to a controller 10 as a motor current detection value IMS. The controller 10 arithmetically determines deviation between the motor current detection value IMS and a desired motor current value IMT preset on the basis of a vehicle speed and a detected steering assist torque value and decides abnormality of the motor current detecting circuit 24 when the deviation indicates an abnormal value over a period equal to or longer than a predetermined time.
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: April 25, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yuji Takatsuka, Shunichi Wada
  • Patent number: 5988310
    Abstract: An electric power steering control system in which the steering "feel" is improved, having a steering force detector an electric motor for producing an auxiliary steering force, a motor current detector and a control unit for deciding the motor current value and rotational direction at least in accordance with the detected steering force. The motor current is limited in accordance with the detected steering force and motor current values.
    Type: Grant
    Filed: September 29, 1998
    Date of Patent: November 23, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Yuji Takatsuka, Shun-Ichi Wada
  • Patent number: 5889376
    Abstract: A motor driving apparatus which makes it possible to continue a suppressed power supply to an electric motor even when a detected value (Id) of a current flowing to an H-bridge circuit indicates abnormality, to thereby prevent occurrence of shock in a system in which the motor is employed as a drive source. The apparatus includes a current detecting device (12) for detecting an electric current (I) flowing to an H-bridge circuit (1), and a control device (20) which includes an abnormality decision device (24) for determining abnormality of the detected current value (Id) outputted from the current detecting device (12). When the detected current value (Id) indicates abnormality, both of the ones (Q1; Q4) of the transistors (Q1; Q2 and Q3; Q4) inserted at the side of the power supply source (3) and the ground (GND), respectively, are driven under the PWM control.
    Type: Grant
    Filed: October 28, 1996
    Date of Patent: March 30, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yuji Takatsuka, Shigeki Ohtagaki
  • Patent number: 5878360
    Abstract: An electric power steering control apparatus is intended to improve the convergence and control stability of a returning motion of a steering wheel when a driver of a vehicle on which the apparatus is installed lets his or her hands free from the steering wheel, and to reduce a burden to the driver when an excessive steering torque occurs during the returning motion. The apparatus includes a steering torque sensor 8 for detecting a steering torque of a steering system of the vehicle, a motor rotational-speed detector 7 for detecting a rotational speed of the electric motor, and a rotational-speed controller for controlling the electric motor based on output signals from the steering torque sensor and the motor rotational-speed sensor so that when the steering torque as detected is less than a predetermined torque value, the rotational speed of the electric motor does not exceed a predetermined speed value corresponding to the predetermined torque value.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: March 2, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Yuji Takatsuka, Shunichi Wada
  • Patent number: 5839537
    Abstract: An electric power steering control system in which the steering "feel" is improved, having a steering force detector an electric motor for producing an auxiliary steering force, a motor current detector and a control unit for deciding the motor current value and rotational direction at least in accordance with the detected steering force. The motor current is limited in accordance with the detected steering force and motor current values.
    Type: Grant
    Filed: September 21, 1995
    Date of Patent: November 24, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Yuji Takatsuka, Shun-Ichi Wada
  • Patent number: 5682314
    Abstract: A controller apparatus for a vehicle includes a computer for controlling devices mounted in the vehicle, and a detector means for detecting the state of the computer immediately before the computer enters a reset state. The computer determines its processing contents on the basis of the detection result of the detection means immediately after the computer is started. Thus, the controller apparatus detects the abnormal reset of the computer in control, thereby assuring the safe control of the devices.
    Type: Grant
    Filed: March 21, 1995
    Date of Patent: October 28, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Yuji Takatsuka, Shunichi Wada
  • Patent number: 5652487
    Abstract: In a electric power steering controller, an output signal of motor driving direction discrimination means is compared with a driving direction discrimination processing result to detect a failure of the motor driving direction discriminator in accordance with the comparison result, so as to prevent the runaway of a motor supplying steering force to a steering wheel.
    Type: Grant
    Filed: August 11, 1995
    Date of Patent: July 29, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Yuji Takatsuka, Shunichi Wada