Patents by Inventor Hirohisa Awa

Hirohisa Awa 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: 6141494
    Abstract: A DC motor driven power steering system for a motor vehicle includes a motor current detection circuit for detecting a motor current flowing through the DC motor, a power supply voltage detection circuit for detecting a power supply voltage applied to the bridge commutation circuit, a motor voltage estimating unit for estimating a voltage applied across the DC motor on the basis of the power supply voltage applied to the bridge commutation circuit and the pulse-width modulated control signals used for controlling the bridge commutation circuit, and a motor rotation detecting means for detecting the rotation state of the DC motor on the basis of the motor current and the estimated motor voltage applied to the DC motor. High reliability can be ensured for detection of the rotation state of the DC motor.
    Type: Grant
    Filed: September 5, 1997
    Date of Patent: October 31, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Hirohisa Awa, Shunichi Wada
  • Patent number: 5996725
    Abstract: A vehicle control apparatus includes a steering torque sensor (1) for sensing a steering torque, a motor (3) for generating a steering assisting force, a CPU (22) for determining a motor drive direction based on at least the steering force and a motor drive direction restricting circuit (25) for restricting the drive direction of the motor (3) determined by the CPU (22) based on a steering force determination level as a motor drive direction determination criterion and the steering force, and the steering force determination level is changeable.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: December 7, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Hirohisa Awa, Shunichi Wada
  • Patent number: 5988312
    Abstract: A vehicle control apparatus includes a steering torque sensor (1) for sensing a steering torque, a motor (3) for generating a steering assisting force, a CPU (22) for determining a motor drive direction based on at least the steering force and a motor drive direction restricting circuit (25) for restricting the drive direction of the motor (3) determined by the CPU (22) based on a steering force determination level as a motor drive direction determination criterion and the steering force, and the steering force determination level is changeable.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: November 23, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Hirohisa Awa, Shunichi Wada
  • Patent number: 5845738
    Abstract: A vehicle control apparatus includes a steering torque sensor (1) for sensing a steering torque, a motor (3) for generating a steering assisting force, a CPU (22) for determining a motor drive direction based on at least the steering force and a motor drive direction restricting circuit (25) for restricting the drive direction of the motor (3) determined by the CPU (22) based on a steering force determination level as a motor drive direction determination criterion and the steering force, and the steering force determination level is changeable.
    Type: Grant
    Filed: March 14, 1996
    Date of Patent: December 8, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Hirohisa Awa, Shunichi Wada
  • Patent number: 5786679
    Abstract: A DC motor driven power steering system for a motor vehicle includes a motor current detection circuit for detecting a motor current flowing through the DC motor, a power supply voltage detection circuit for detecting a power supply voltage applied to the bridge commutation circuit, a motor voltage estimating unit for estimating a voltage applied across the DC motor on the basis of the power supply voltage applied to the bridge commutation circuit and the pulse-width modulated control signals used for controlling the bridge commutation circuit, and a motor rotation detecting means for detecting the rotation state of the DC motor on the basis of the motor current and the estimated motor voltage applied to the DC motor. High reliability can be ensured for detection of the rotation state of the DC motor.
    Type: Grant
    Filed: March 20, 1995
    Date of Patent: July 28, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Hirohisa Awa, Shunichi Wada
  • Patent number: 5698956
    Abstract: A control system for an electrically operated power steering apparatus which is capable of eliminating an incongruous steering sensation and improving the converging performance of a steering wheel. The control system comprises a steering torque detecting unit 20 for detecting a steering torque applied to a steering system, a motor 10 coupled to the steering system, and a control unit for controlling the motor 10 using an output of the steering torque detecting unit 20 phase-compensated on the basis of a speed of the motor 10. The control unit includes a target current determining section 25 for determining a target current to the motor 10 on the basis of the output of the steering torque detecting unit 20 and a phase compensating section 21 for obtaining a phase compensation value on the basis of the output of the steering torque detecting unit 20 and the speed of the motor 10. The target current is corrected by the phase compensation value.
    Type: Grant
    Filed: January 3, 1996
    Date of Patent: December 16, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Hirohisa Awa
  • Patent number: 5659472
    Abstract: [Object] To improve system reliability and safety. [Constitution] The rotation speed of the motor 6 is detected by the motor rotation speed detection circuit 17 and the amount of rotation of the motor 6 is calculated from the detected rotation speed by the motor rotation amount calculating means 10a. Then, a fault is determined when the amount of rotation exceeds a predetermined value and the drive of the motor 6 is stopped by the motor stopping means 123.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: August 19, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazuhisa Nishino, Hirohisa Awa, Shunichi Wada
  • Patent number: 5504679
    Abstract: A control apparatus for an electric motor-driven power steering system includes a main CPU for arithmetically determining the steering assist torque to be generated by the electric motor and a driving direction thereof on the basis of outputs of a torque sensor and the vehicle speed sensor, a subsidiary CPU for arithmetically determining the driving direction of the motor on the basis of outputs of the torque sensor and the vehicle speed sensor and compare the driving direction signal supplied from the main CPU with a signal of the driving direction determined by the subsidiary CPU to generate a second driving direction signal. A coincidence/discrepancy signal representing coincidence or discrepancy between the motor driving direction signal and the steering torque signal is also supplied to the subsidiary CPU from the main CPU.
    Type: Grant
    Filed: February 9, 1994
    Date of Patent: April 2, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shunichi Wada, Kazuhisa Nishino, Hirohisa Awa