Patents by Inventor Takayuki Kifuku

Takayuki Kifuku 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: 8604734
    Abstract: In an electric motor control apparatus, an electric motor driving unit includes: a current detection unit configured to detect a current flowing through a current detection place in the electric motor driving unit. A control unit includes a current calculation unit configured to calculate a current value of a current flowing through an electric motor from an offset correction value obtained based on a first detection value detected at a time when a current flows through the current detection place and a second detection value detected at a time when a current does not flow through the current detection place. The offset correction value includes: a first offset correction value stored in nonvolatile memory of the control unit at a time of assembling the electric motor control apparatus; and a second offset correction value computed by the control unit while the electric motor is driven.
    Type: Grant
    Filed: March 30, 2010
    Date of Patent: December 10, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masaki Matsushita, Takayuki Kifuku, Yasuaki Hori
  • Patent number: 8548684
    Abstract: To obtain an electric power steering control apparatus hard to generate vibration even when accuracy is not high enough for torque vibration of extremely small output of torque detecting means.
    Type: Grant
    Filed: November 4, 2008
    Date of Patent: October 1, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masahiko Kurishige, Takayuki Kifuku, Koji Nagao
  • Publication number: 20130124049
    Abstract: An electric power steering system includes steering a torque detector that detects steering torque, and a motor that provides assist torque based on the detected steering torque, wherein for the purpose of estimating, without detecting motor rotation angular information and rotation angular velocity information, the road reaction torque in which the influence of the motor inertia torque is eliminated, a value corresponding to rotation velocity of a steering shaft is calculated based on the steering torque and the assist torque, to calculate road reaction torque based on the value corresponding to the rotation velocity of the steering shaft.
    Type: Application
    Filed: July 13, 2011
    Publication date: May 16, 2013
    Applicant: Mitsubishi Electric Corporation
    Inventors: Masaya Endo, Takashi Iwasaki, Masahiko Kurishige, Takayuki Kifuku, Yoshihiko Kinpara
  • Publication number: 20130041557
    Abstract: An automatic steering apparatus that can suppress steering wheel vibration and that can also smooth angular control. In the automatic steering apparatus, a motor that steers steered wheels is controlled by a control unit. Information from an angle sensor that generates a signal that corresponds to a steering angle of the steered wheels is sent to the control unit. The control unit corrects a target steering angle of the steered wheels such that angular acceleration of the target steering angle is less than or equal to a limiting value. The control unit controls the motor such that the steering angle of the steered wheels tracks the corrected target steering angle based on the information from the angle sensor.
    Type: Application
    Filed: May 18, 2011
    Publication date: February 14, 2013
    Applicant: Mitsubishi Electric Corporation
    Inventors: Masaya Endo, Masahiko Kurishige, Kenji Ogawa, Takayuki Kifuku, Hiroyuki Kozuki
  • Patent number: 8363420
    Abstract: The apparatus includes a housing, a heat sink arranged in the housing, semiconductor switching elements mounted on the heat sink and having terminals, a circuit board arranged in opposition to the heat sink and having an electronic circuit formed thereon including a control circuit for controlling the semiconductor switching elements, and a plurality of conductive plates electrically connecting the circuit board and the semiconductor switching elements to each other. The individual conductive plates are arranged along a lead-out direction in which the individual terminals of the semiconductor switching elements lead out, so that they are bonded to the individual terminals.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: January 29, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Tsutomu Tominaga, Masahiro Kimata, Takayuki Kifuku, Shuzo Akiyama, Tadayuki Fujimoto
  • Publication number: 20130014583
    Abstract: In an angle detection method with a resolver, the method being for detecting a rotational angle of a rotator by synchronously detecting a first signal and a second signal that are two phase sine wave modulation signals obtained from a one phase excitation/two phase output resolver, the method includes: a first signal detection process which detects a signal in the order of the first signal and the second signal; and a second signal detection process which detects a signal in the order of the second signal and the first signal.
    Type: Application
    Filed: February 13, 2012
    Publication date: January 17, 2013
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yoshihiko KIMPARA, Yasuaki HORI, Tatsuya MORI, Takayuki KIFUKU, Takahiro OKANOUE
  • Patent number: 8346435
    Abstract: Provided is an electric power steering control device capable of performing damping control without current detection to perform stable damping control even when a target current and an actual current value differ from each other. The electric power steering control device includes steering torque detection means for detecting a steering torque, a torque controller for computing an assist torque current, a motor for generating a torque for assisting the steering torque, rotation speed estimation means for estimating a rotation speed of the motor, and a damping controller for computing a damping current by using an estimated value of the rotation speed of the motor.
    Type: Grant
    Filed: October 8, 2008
    Date of Patent: January 1, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masahiko Kurishige, Takayuki Kifuku, Koji Nagao
  • Patent number: 8326493
    Abstract: A motor-driven power steering control apparatus is achieved, which uses a small-amplitude pass filter, the filter filtering out a component having a small amplitude, to remove a steering component from dynamic state quantity such as a rotational speed signal, and to accurately extract only a vibration component having a small amplitude compared with the steering component, and controls the vibration component to be reduced.
    Type: Grant
    Filed: December 14, 2007
    Date of Patent: December 4, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventors: Isao Kezobo, Masahiko Kurishige, Masaya Endo, Takayuki Kifuku, Seiji Sawada, Masaki Matsushita
  • Publication number: 20120296525
    Abstract: In a steering control device, a road surface reaction force torque calculation module (52) uses a vehicle speed, steering angle, and vehicle model to calculate a caster-trail-caused torque, a self-aligning torque, and a road surface reaction force torque. A reaction force command current calculation module (53) uses the road surface reaction force torque and the vehicle speed to calculate a reaction force command current.
    Type: Application
    Filed: February 19, 2010
    Publication date: November 22, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Masaya Endo, Masahiko Kurishige, Takayuki Kifuku, Masaki Matsushita, Hideki Doi
  • Publication number: 20120273290
    Abstract: Provided is a motor control device including a main calculation unit (101), which takes a first operation state for controlling a brushless motor (5), and a second operation state for stopping the motor control, and a sub calculation unit (102) for monitoring the main calculation unit (101) by means of a first monitoring unit (106) in the first state, for calculating a motor rotation angle in the second state, thereby enabling continuous calculation of the motor rotation angle even when the motor control is stopped, for carrying out monitoring the sub calculation unit (102) by means of second monitoring unit (201), thereby securing reliability, and for calculating the motor rotation angle in a second calculation cycle in the second operation state, the second calculation cycle being longer than a first calculation cycle in the first operation state, thereby reducing a current consumption.
    Type: Application
    Filed: October 5, 2011
    Publication date: November 1, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yu KAWANO, Masatoshi Saito, Takayuki Kifuku
  • Patent number: 8294395
    Abstract: A storage section stores three-phase detection currents and outputs them as three-phase storage detection currents and also stores three-phase voltage commands and outputs them as three-phase storage voltage commands. A second voltage command calculating section outputs three-phase voltage commands on the basis of the three-phase storage detection currents and the three-phase storage voltage commands, which are acquired from the storage section, and the three-phase detection currents acquired from a current detecting means. A voltage command output means outputs, to a voltage application means, three-phase voltage commands acquired on the basis of the three-phase voltage commands from the storage section and the three-phase voltage commands from the second voltage command calculating section. The voltage application means applies a voltage to an AC rotary machine on the basis of the three-phase voltage commands from the voltage command output means.
    Type: Grant
    Filed: October 14, 2010
    Date of Patent: October 23, 2012
    Assignee: Mitsubishi Electric Corp.
    Inventors: Yoshihiko Kimpara, Seiji Sawada, Takayuki Kifuku
  • Patent number: 8265829
    Abstract: A steering control system is connectable to a motor configured to control a steering and a LAN (Local Area Network) and is allowed to receive a control signal for controlling said motor from the LAN is received. The steering control system includes: a motor configured to control a steering; a main calculation unit connectable to the LAN; a motor drive circuit connected to the main calculation unit and configured to drive the motor; a sub calculation unit connectable to the LAN; and a motor drive limiting unit connected to the sub calculation unit and configured to limit a drive of the motor.
    Type: Grant
    Filed: May 12, 2008
    Date of Patent: September 11, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masaki Matsushita, Takayuki Kifuku, Hiroyuki Kozuki
  • Publication number: 20120206075
    Abstract: A power inverter is provided that can apply to an AC rotary machine three-phase voltages of high amplitudes and low distortion while suppressing ohmic loss attributed to current detection resisters. The power inverter includes a superimposed voltage command computing means for computing and outputting a superimposed voltage command depending on the difference between a maximum value and a minimum value of three-phase voltage commands; a voltage command modification means for adding the superimposed voltage command to each of the three-phase voltage commands and outputting modified three-phase voltage commands; and a power output means for outputting the three-phase voltages based on the modified three-phase voltage commands.
    Type: Application
    Filed: July 15, 2011
    Publication date: August 16, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yoshihiko KIMPARA, Takayuki KIFUKU, Tatsuya MORI
  • Patent number: 8232752
    Abstract: An electric motor control apparatus that can quickly and accurately locate a short-circuit fault point. The electric motor control apparatus includes: a current controller determining respective phase voltage commands according to currents flowing in respective phases of an electric motor and a torque current command; a switching element drive circuit instructing, based on the respective phase voltage commands, an inverter to perform a switching operation; the inverter receiving a switching operation signal to drive the electric motor; current detectors disposed in series with the switching elements in the respective phases of the inverter; and a short-circuit point locating mechanism storing a test pattern indicative of a predetermined combination for turning on the switching elements of the inverter, and locating a short-circuit fault point based on the test pattern and current detection values in the respective phases detected by the current detectors in response to the test pattern.
    Type: Grant
    Filed: April 16, 2007
    Date of Patent: July 31, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventors: Isao Kezobo, Masahiro Kimata, Takayuki Kifuku, Kazumichi Tsutsumi, Chiaki Fujimoto, Noriyuki Inoue
  • Publication number: 20120185132
    Abstract: An electric power steering control device includes: a vibration extracting filter for performing filter processing on a rotation speed of a motor to reduce a gain on a low frequency side so as to output a vibration-component signal; a current variable gain map for detecting a current flowing through the motor as a first state quantity so as to calculate a current variable gain based on the current; a rotation-speed variable gain map for detecting the rotation speed of the motor as a second state quantity so as to calculate a rotation-speed variable gain based on the rotation speed; a correction mechanism calculating a vibration suppression current; and current controller calculating a target current so as to control the current flowing through the motor.
    Type: Application
    Filed: October 21, 2010
    Publication date: July 19, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Isao Kezobo, Masahiko Kurishige, Masaya Endo, Takayuki Kifuku
  • Patent number: 8165754
    Abstract: A steering control system is connectable to a motor configured to control a steering and a LAN (Local Area Network) and is allowed to receive a control signal for controlling said motor from the LAN is received. The steering control system includes: a motor configured to control a steering; a main calculation unit connectable to the LAN; a motor drive circuit connected to the main calculation unit and configured to drive the motor; a sub calculation unit connectable to the LAN; and a motor drive limiting unit connected to the sub calculation unit and configured to limit a drive of the motor.
    Type: Grant
    Filed: May 12, 2008
    Date of Patent: April 24, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masaki Matsushita, Takayuki Kifuku, Hiroyuki Kozuki
  • Publication number: 20120057381
    Abstract: There is provided an electric-power conversion apparatus including a chopper circuit; a current sense resistor that detects the output current of the chopper circuit; a differential detection circuit that outputs, as a differential detection signal (vo), the electric potential difference across the current sense resistor; and a calculation means that corrects the differential detection signal (vo) from the differential detection circuit by use of a control signal (D1) for the chopper circuit so as to calculate the output current (i0) of the chopper circuit.
    Type: Application
    Filed: March 3, 2011
    Publication date: March 8, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yoshihiko KIMPARA, Takayuki KIFUKU, Tetsuya KOJIMA, Tatsuya MORI
  • Publication number: 20110264330
    Abstract: An electric power steering apparatus includes an rotating AC machine which generates an auxiliary torque for assisting a steering torque of a steering system; and a controller which performs control so that the allowed electric current amplitude of the rotating AC machine becomes large if a rotational speed of the rotating AC machine is increased. Accordingly, it is possible to release or lessen the limit on the number of repetitions or continuous time of the “stationary steering” or the “end contact”.
    Type: Application
    Filed: November 16, 2010
    Publication date: October 27, 2011
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yoshihiko KIMPARA, Takayuki KIFUKU, Masatsugu NAKANO
  • Patent number: 8046131
    Abstract: Provided is a vehicular steering apparatus capable of improving a steering feeling and achieving a reduction in cost. The vehicular steering apparatus according to the present invention is equipped with an assist motor for generating an assist torque, a state quantity detector for detecting a steering shaft reaction torque and a road surface reaction torque, and a control unit for calculating a target current value of the assist motor. The control unit includes a friction compensation portion and a return compensation portion, which calculate a friction compensation torque for compensating for the assist torque and a return compensation torque for compensating for the assist torque from the steering shaft reaction torque and the road surface reaction torque respectively. The control unit compensates for an overall friction torque in a steering mechanism and a gradient of the road surface reaction torque, using the friction compensation torque and the return compensation torque.
    Type: Grant
    Filed: November 2, 2006
    Date of Patent: October 25, 2011
    Assignee: Mitsubishi Electric Corporation
    Inventors: Hideyuki Tanaka, Takanori Matsunaga, Masahiko Kurishige, Takayuki Kifuku
  • Publication number: 20110241579
    Abstract: A storage section stores three-phase detection currents and outputs them as three-phase storage detection currents and also stores three-phase voltage commands and outputs them as three-phase storage voltage commands. A second voltage command calculating section outputs three-phase voltage commands on the basis of the three-phase storage detection currents and the three-phase storage voltage commands, which are acquired from the storage section, and the three-phase detection currents acquired from a current detecting means. A voltage command output means outputs, to a voltage application means, three-phase voltage commands acquired on the basis of the three-phase voltage commands from the storage section and the three-phase voltage commands from the second voltage command calculating section. The voltage application means applies a voltage to an AC rotary machine on the basis of the three-phase voltage commands from the voltage command output means.
    Type: Application
    Filed: October 14, 2010
    Publication date: October 6, 2011
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yoshihiko KIMPARA, Seiji Sawada, Takayuki Kifuku