Patents by Inventor Takanobu Takamatsu

Takanobu Takamatsu 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: 8538632
    Abstract: An electric power steering apparatus is provided that has a controller by which no current flows in one phase among current paths of three phases for supplying electric power from a motor driving circuit to a three-phase brushless motor and currents that have an identical absolute value and that have different signs flow in the other two phases. Thus, the status at one energization angle on the driving current waveform of the three-phase brushless motor can be given continuously and relatively-high currents can simultaneously flow in opposite directions in the contacts inserted to the two phases. By flowing of such high current in the contacts, a secure conduction check can be performed and foreign matters on the surface of the contact can be fused or thermally destroyed.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: September 17, 2013
    Assignees: JTEKT Corporation, Mitsubishi Electric Corporation
    Inventors: Takanobu Takamatsu, Ryouichi Suzuki, Yuuichi Fukuyama, Yuji Takatsuka
  • Publication number: 20090150027
    Abstract: An electric power steering apparatus is provided that has a controller by which no current flows in one phase among current paths of three phases for supplying electric power from a motor driving circuit to a three-phase brushless motor and currents that have an identical absolute value and that have different signs flow in the other two phases. Thus, the status at one energization angle on the driving current waveform of the three-phase brushless motor can be given continuously and relatively-high currents can simultaneously flow in opposite directions in the contacts inserted to the two phases. By flowing of such high current in the contacts, a secure conduction check can be performed and foreign matters on the surface of the contact can be fused or thermally destroyed.
    Type: Application
    Filed: October 21, 2008
    Publication date: June 11, 2009
    Inventors: Takanobu Takamatsu, Ryouichi Suzuki, Yuuichi Fukuyama, Yuji Takatsuka
  • Patent number: 7009358
    Abstract: The present invention provides an electric power steering device enabled to compensate for the influence of the inertia of a steering-assisting-force generating motor on steering with accurate timing even when a steering direction is reversed at high speed. Based on steering torque and a rotation angular speed of a steering-assisting-force generating motor, a steering angular acceleration correspondence value is obtained. The device has means for regulating a gain, which is multiplied to a change acceleration of the steering torque. The motor is controlled so that the steering assisting force is corrected according to a motor output correction value obtained on the basis of the relation between the motor output correction value and the steering angular acceleration correspondence value, which is preliminarily determined and stored in such a way as to compensate for the influence of the inertia on steering, and the obtained steering angular acceleration correspondence value.
    Type: Grant
    Filed: October 30, 2003
    Date of Patent: March 7, 2006
    Assignee: Koyo Seiko Co., Ltd.
    Inventors: Terutaka Tamaizumi, Yoshinobu Shimizu, Shinya Aono, Akihiro Nishiyama, Takanobu Takamatsu, Masayuki Kita, Tomoyuki Yamauchi
  • Publication number: 20040140788
    Abstract: The present invention provides an electric power steering device enabled to compensate for the influence of the inertia of a steering-assisting-force generating motor on steering with accurate timing even when a steering direction is reversed at high speed. Based on steering torque and a rotation angular speed of a steering-assisting-force generating motor, a steering angular acceleration correspondence value is obtained. The device has means for regulating a gain, which is multiplied to a change acceleration of the steering torque. The motor is controlled so that the steering assisting force is corrected according to a motor output correction value obtained on the basis of the relation between the motor output correction value and the steering angular acceleration correspondence value, which is preliminarily determined and stored in such a way as to compensate for the influence of the inertia on steering, and the obtained steering angular acceleration correspondence value.
    Type: Application
    Filed: October 30, 2003
    Publication date: July 22, 2004
    Applicant: Koyo Seiko Co., Ltd.
    Inventors: Terutaka Tamaizumi, Yoshinobu Shimizu, Shinya Aono, Akihiro Nishiyama, Takanobu Takamatsu, Masayuki Kita, Tomoyuki Yamauchi
  • Patent number: 6698542
    Abstract: The steering device for vehicle changes the steering angle by transmitting the movements of the steering electrical actuator to the vehicle wheels. When the vehicle is steered in the stationary state, the hydraulic fluid can be supplied to the steering assistance force generating hydraulic actuator from the pump within the hydraulic pressure imparting unit. When the vehicle is not steered in the stationary state, the hydraulic fluid can be supplied to the brake device from the pump via the hydraulic pressure distribution unit.
    Type: Grant
    Filed: February 13, 2002
    Date of Patent: March 2, 2004
    Assignees: Koyo Seiko Co., Ltd., Sumimoto (SEI) Brake Systems, Inc.
    Inventors: Katsutoshi Nishizaki, Shirou Nakano, Takanobu Takamatsu, Masaya Segawa, Ryouhei Hayama, Kazuhiro Kato
  • Patent number: 6516916
    Abstract: In a steering device, the rotation of the input shaft corresponding to the steering operation is transmitted to the output shaft via a rotation transmission mechanism, and is transmitted from the output shaft to the wheels of the vehicle by a steering gear so that the steering angle varies. A control device controls an electromotive actuator used to drive a constituent element of the rotation transmission mechanism in accordance with a variable quantity that expresses the traveling conditions of the vehicle, on the basis of the respective detection values of an input sensor used to detect the amount of input into the input shaft, an output sensor used to detect the amount of output of the output shaft and a traveling condition sensor used to detect the variable quantity that expresses the traveling conditions of the vehicle, so that the ratio of the transmission of rotation from the input shaft to the output shaft is altered in accordance with the variable quantity that expresses the traveling conditions.
    Type: Grant
    Filed: February 20, 2002
    Date of Patent: February 11, 2003
    Assignee: Koyo Seiko Co., Ltd.
    Inventors: Masaya Segawa, Shirou Nakano, Katsutoshi Nishizaki, Ryouhei Hayama, Takanobu Takamatsu, Masanori Arima
  • Patent number: 6449543
    Abstract: In a steering device for vehicle, the movement of a steering actuator, which is driven in accordance with the rotating operation of an operating member, is transmitted to the vehicle wheels such that the steering angle changes without mechanically coupling the operating member to the wheels. A target yaw rate, which accords with a load torque, that is sum of the control torque generated by an operating actuator and driver operating torque, and an operating angle of the operating member resulting from the functioning of this load torque, are computed. The steering actuator is controlled such that the vehicle yaw rate follows the target yaw rate. The operating actuator is controlled such that the operating angle follows a target operating angle of the operating member corresponding to a behavior index value comprising at least yaw rate of the vehicle.
    Type: Grant
    Filed: January 16, 2001
    Date of Patent: September 10, 2002
    Assignee: Koyo Seiko Co., Ltd.
    Inventors: Katsutoshi Nishizaki, Shiro Nakano, Takanobu Takamatsu, Masaya Segawa
  • Publication number: 20020121400
    Abstract: In a steering device, the rotation of the input shaft corresponding to the steering operation is transmitted to the output shaft via a rotation transmission mechanism, and is transmitted from the output shaft to the wheels of the vehicle by a steering gear so that the steering angle varies. A control device controls an electromotive actuator used to drive a constituent element of the rotation transmission mechanism in accordance with a variable quantity that expresses the traveling conditions of the vehicle, on the basis of the respective detection values of an input sensor used to detect the amount of input into the input shaft, an output sensor used to detect the amount of output of the output shaft and a traveling condition sensor used to detect the variable quantity that expresses the traveling conditions of the vehicle, so that the ratio of the transmission of rotation from the input shaft to the output shaft is altered in accordance with the variable quantity that expresses the traveling conditions.
    Type: Application
    Filed: February 20, 2002
    Publication date: September 5, 2002
    Applicant: Koyo Seiko Co., Ltd.
    Inventors: Masaya Segawa, Shirou Nakano, Katsutoshi Nishizaki, Ryouhei Hayama, Takanobu Takamatsu, Masanori Arima
  • Publication number: 20020117347
    Abstract: The steering device for vehicle changes the steering angle by transmitting the movements of the steering electrical actuator to the vehicle wheels. When the vehicle is steered in the stationary state, the hydraulic fluid can be supplied to the steering assistance force generating hydraulic actuator from the pump within the hydraulic pressure imparting unit. When the vehicle is not steered in the stationary state, the hydraulic fluid can be supplied to the brake device from the pump via the hydraulic pressure distribution unit.
    Type: Application
    Filed: February 13, 2002
    Publication date: August 29, 2002
    Inventors: Katsutoshi Nishizaki, Shirou Nakano, Takanobu Takamatsu, Masaya Segawa, Ryouhei Hayama, Kazuhiro Kato
  • Patent number: 6415212
    Abstract: In a steering device for a vehicle, the movement of a steering actuator driven by operation of an operating member is transmitted to vehicle wheels, in such a manner that the steering angle changes, without the operating member being coupled mechanically to the vehicle wheels. A first target yaw rate is calculated in accordance with the detected vehicle speed and a first steering angle set value, which corresponds to the detected amount of operation and vehicle speed. A second target yaw rate corresponding to the detected lateral acceleration and vehicle speed is calculated. A second steering angle set value, which corresponds to the difference between the detected yaw rate and a target yaw rate, as which the first target yaw rate or the second target yaw rate whichever has the smaller absolute value is taken, is calculated.
    Type: Grant
    Filed: January 17, 2001
    Date of Patent: July 2, 2002
    Assignees: Koyo Seiko Co., Ltd., Sumitomo (SEI) Brake Systems, Inc.
    Inventors: Katsutoshi Nishizaki, Shiro Nakano, Takanobu Takamatsu, Masaya Segawa
  • Patent number: 6364051
    Abstract: An electric power steering system which assists a steering operation by controlling an electric motor on the basis of a target electric current determined in accordance with a steering torque applied to an operation member and applying a driving force to a steering mechanism from the electric motor. The system includes steering torque detecting section; target electric current determining circuit for determining a target electric current in accordance with the steering torque on the basis of an assist characteristic; and motor controlling circuit for controlling the electric motor on the basis of the target electric current. The assist characteristic is offset from an initial characteristic when a motor vehicle incorporating the system is in a predetermined turning state.
    Type: Grant
    Filed: October 5, 2000
    Date of Patent: April 2, 2002
    Assignee: Koyo Seiko Co., Ltd.
    Inventors: Tomoyasu Kada, Shiro Nakano, Katsutoshi Nishizaki, Takanobu Takamatsu, Masaya Segawa, Ryouhei Hayama
  • Patent number: 6349789
    Abstract: A steering device for vehicles transmits steering torque applied by the driver to wheels. When at least one of braking force and driving force of the wheels is controlled for stabilization of vehicle behavior, steering torque is controlled to cancel out change in the steering torque due to the stabilization according to change in at least one of the braking force and driving force due to the control for the stabilization.
    Type: Grant
    Filed: April 27, 2000
    Date of Patent: February 26, 2002
    Assignee: Koyo Seiko Co., Ltd.
    Inventors: Shiro Nakano, Katsutoshi Nishizaki, Masaya Segawa, Naoki Maeda, Takanobu Takamatsu
  • Patent number: 6308122
    Abstract: Motor vehicle steering system for driving a steering mechanism on the basis of an operation angle of an operation mechanism. The system includes: a behavioral variable computation section for performing computation on a behavioral variable indicative of a behavior of a motor vehicle; and a steering angle controlling section for sequentially updating a relationship between a steering angle of vehicle wheels and the operation angle of the operation mechanism on the basis of a value of the behavioral variable computed by the behavioral variable computation section and a preset target value of the behavioral variable and controlling the steering mechanism on the basis of the updated relationship. The behavioral variable may be a steady-state gain which is a steady-state ratio of the steering angle of the vehicle wheels to the operation angle of the operation mechanism.
    Type: Grant
    Filed: April 25, 2000
    Date of Patent: October 23, 2001
    Assignees: Koyo Seiko Co., Ltd, Sumitomo Electric Industries, Ltd.
    Inventors: Katsutoshi Nishizaki, Takanobu Takamatsu, Masaya Segawa
  • Publication number: 20010027893
    Abstract: In a steering device for a vehicle, the movement of a steering actuator driven by operation of an operating member is transmitted to vehicle wheels, in such a manner that the steering angle changes, without the operating member being coupled mechanically to the vehicle wheels. A first target yaw rate is calculated in accordance with the detected vehicle speed and a first steering angle set value, which corresponds to the detected amount of operation and vehicle speed. A second target yaw rate corresponding to the detected lateral acceleration and vehicle speed is calculated. A second steering angle set value, which corresponds to the difference between the detected yaw rate and a target yaw rate, as which the first target yaw rate or the second target yaw rate whichever has the smaller absolute value is taken, is calculated.
    Type: Application
    Filed: January 17, 2001
    Publication date: October 11, 2001
    Applicant: Koyo Seiko Co., Ltd. SUMITOMO(SEI) BRAKE SYSTEMS, INC.
    Inventors: Katsutoshi Nishizaki, Shiro Nakano, Takanobu Takamatsu, Masaya Segawa
  • Publication number: 20010011201
    Abstract: In a steering device for vehicle, the movement of a steering actuator, which is driven in accordance with the rotating operation of an operating member, is transmitted to the vehicle wheels such that the steering angle changes without mechanically coupling the operating member to the wheels. A target yaw rate, which accords with a load torque, that is sum of the control torque generated by an operating actuator and driver operating torque, and an operating angle of the operating member resulting from the functioning of this load torque, are computed. The steering actuator is controlled such that the vehicle yaw rate follows the target yaw rate. The operating actuator is controlled such that the operating angle follows a target operating angle of the operating member corresponding to a behavior index value comprising at least yaw rate of the vehicle.
    Type: Application
    Filed: January 16, 2001
    Publication date: August 2, 2001
    Applicant: Koyo Seiko Co., Ltd.
    Inventors: Katsutoshi Nishizaki, Shiro Nakano, Takanobu Takamatsu, Masaya Segawa
  • Patent number: 5433305
    Abstract: An assembly includes an overrunning clutch, a rolling bearing and a casing supporting them. An overrunning clutch-supporting portion of the casing has inwardly protruding portions that inter-engage with raised portions on an outer ring of the overrunning clutch in the direction of rotation of the outer ring. As a result, a clearance is defined between the inwardly protruding portions of the overrunning clutch-supporting portion and the raised portions of the outer ring. The overrunning clutch is automatically centered to a rotation shaft when used. An elastic ring is interposed in a predetermined compressed state between the outer ring and the overrunning clutch-supporting portion. Frictional resistance is produced between the outer ring and the overrunning clutch-supporting portion preventing the overrunning clutch from becoming shaky in the casing. The overrunning clutch is pressed against the casing by a spacer to produce the same frictional resistance between the overrunning clutch and the casing.
    Type: Grant
    Filed: June 17, 1993
    Date of Patent: July 18, 1995
    Assignee: Koyo Seiko Co., Ltd.
    Inventors: Takanobu Takamatsu, Kazuo Iga