Patents by Inventor Toshiyuki Koterazawa

Toshiyuki Koterazawa 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: 5239490
    Abstract: This specification discloses inventions of a rotation detecting device for a rotary shaft and of a rotation controlling apparatus using this rotation detecting device. The rotation detecting device according to the invention comprises a signal generator for generating two signals vary their amplitude in accordance with the rotation angle of the rotary shaft and have a predetermined phase difference therebetween, part for correcting the respective center voltages output from the signal generator, part for correcting a deviation from the phase deviation between the two signals, and part for correcting the rotating amounts of the rotary shaft on the basis of the corrected two signal. The rotating amounts are represented in terms of rotating angles. A rotating torque can be obtained by calculating a difference between the rotating angles measured at two points apart from each other on the rotary shaft. The rotary shaft can be controlled in accordance with the rotating angle or the rotating torque.
    Type: Grant
    Filed: September 12, 1990
    Date of Patent: August 24, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Ryoso Masaki, Toshiyuki Koterazawa, Kazuo Tahara, Kunio Miyashita, Yoshikazu Hoshi, Tadashi Takahashi, Shuichi Nakano
  • Patent number: 5033565
    Abstract: A generator generates two voltage outputs which have different voltage levels. One voltage output from the generator is used for operating a power steering apparatus. Another voltage output from the generator is used for charging a battery which supplies current to other loads.
    Type: Grant
    Filed: October 18, 1989
    Date of Patent: July 23, 1991
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Toshimi Abukawa, Toshiaki Okuyama, Kazuo Tahara, Katsuji Marumoto, Toshiyuki Koterazawa, Mitsuyuki Hombu, Tadashi Takahashi, Hisatugu Ishikura, Hiroshisa Yamamura, Toru Tatsuzaki, Tsutomu Omae, Shuichi Takamatsu
  • Patent number: 4960178
    Abstract: A generator generates two voltage outputs which have different voltage levels. One voltage output from the generator is used for operating a power steering apparatus. Another voltage output from the generator is used for charging a battery which supplies current to other loads.
    Type: Grant
    Filed: September 22, 1988
    Date of Patent: October 2, 1990
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Toshimi Abukawa, Toshiaki Okuyama, Kazuo Tahara, Katsuji Marumoto, Toshiyuki Koterazawa, Mitsuyuki Hombu, Tadashi Takahashi, Hisatugu Ishikura, Hirohisa Yamamura, Toru Tatsuzaki, Tsutomu Omae, Shuichi Takamatsu
  • Patent number: 4875539
    Abstract: An electric power steering control system includes an electric motor for producing an assisting torque for the vehicle steering system through a reduction gear, a steering torque sensor fitted on the steering shaft, a controller for controlling the input to the motor in accordance with the torque sensor output, a battery for supplying power to the controller, and a voltage step-up circuit connected to the battery for driving the motor at a voltage higher than the battery voltage. The controller drives the motor at a high voltage.
    Type: Grant
    Filed: March 31, 1988
    Date of Patent: October 24, 1989
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Toshimi Abukawa, Kazuo Tahara, Katsuji Murumoto, Toshiyuki Koterazawa, Mitsuyuki Hombu, Tadashi Takahashi, Shuichi Takamatsu, Hisatugu Ishikura, Hiroshisa Yamamura, Toru Tatsuzaki, Tsutomu Ohmae, Toshiaki Okuyama, Seizi Yamashita, Shigeki Saito, Masato Sakai
  • Patent number: 4869334
    Abstract: The steering power assist control comprises a main assist control and an auxiliary assist control. When an abnormality occurrence signal from the main assist control is inputted to an abnormality state detection and changing decision circuit 134, the selector circuit changes the PWM signal from the main assist control side to the auxiliary assist control side and outputs the PWM signal to a motor drive circuit. When the main assist control fails, the auxiliary assist control immediately takes over the main assist control to provide, if the operation condition permits, a continued steering power assist control. This prevents an abnormal steering state of the vehicle that would otherwise result when the steering power assist is suddenly lost.
    Type: Grant
    Filed: April 13, 1988
    Date of Patent: September 26, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Katsuji Marumoto, Tsutomu Ohmae, Toshiyuki Koterazawa, Kazuaki Tobari
  • Patent number: 4865148
    Abstract: A vehicle height control apparatus responsive to power steering operation is disclosed in which a torque signal indicative of the steering torque imparted to the steering wheel by a driver's operation thereof is used for controlling the power steering system and also for controlling the operation of actuators for adjusting damping force of shock absorber provided to each wheel thereby controlling the height of the vehicle.
    Type: Grant
    Filed: August 9, 1988
    Date of Patent: September 12, 1989
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineer Co., Ltd.
    Inventors: Katsuji Marumoto, Kazuo Tahara, Hisatugu Ishikura, Hirohisa Yamamura, Toru Tatsuzaki, Toshimi Abukawa, Toshiyuki Koterazawa, Mitsuyuki Honbu, Tadashi Takahashi, Shuichi Takamatsu, Tsutomu Ohmae