Patents by Inventor Toru Tazawa

Toru Tazawa 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: 8378615
    Abstract: There are provided: a plurality of notch filters which are arranged inside a control system for feedback-controlling a moving operation of a moving section of a motor and attenuate signal components having near frequencies with a notch frequency at a center in an input signal; a plurality of oscillation extracting filters which are set with different frequency bands as being corresponded to the respective notch filters and extract oscillating components in the set frequency bands from a speed detection signal; and a plurality of notch controlling sections which are arranged with respect to the respective oscillation extracting filters and control the notch frequencies of the corresponding notch filters so as to decrease amplitudes of the oscillating components extracted by the oscillation extracting filters.
    Type: Grant
    Filed: June 1, 2009
    Date of Patent: February 19, 2013
    Assignee: Panasonic Corporation
    Inventors: Toru Tazawa, Hiroshi Fujiwara, Masaru Nishizono
  • Patent number: 8375317
    Abstract: An evaluation index selection section in which any evaluation index is selected from a plurality of evaluation indices of the control characteristics in the motor control system and which outputs selection information indicating the selected evaluation index; a relational data extraction section for extracting data related to the selected evaluation index from a data group of the motor control system based on the selection information; an evaluation value calculation section for calculating an evaluation value of the evaluation index based on the extracted data; and a display control section for displaying the calculated evaluation value on a display are included.
    Type: Grant
    Filed: January 27, 2009
    Date of Patent: February 12, 2013
    Assignee: Panasonic Corporation
    Inventors: Yukihiro Yamaichi, Toru Tazawa, Ken'ichi Suzuki
  • Publication number: 20110221378
    Abstract: There are provided: a plurality of notch filters which are arranged inside a control system for feedback-controlling a moving operation of a moving section of a motor and attenuate signal components having near frequencies with a notch frequency at a center in an input signal; a plurality of oscillation extracting filters which are set with different frequency bands as being corresponded to the respective notch filters and extract oscillating components in the set frequency bands from a speed detection signal; and a plurality of notch controlling sections which are arranged with respect to the respective oscillation extracting filters and control the notch frequencies of the corresponding notch filters so as to decrease amplitudes of the oscillating components extracted by the oscillation extracting filters.
    Type: Application
    Filed: June 1, 2009
    Publication date: September 15, 2011
    Applicant: PANASONIC CORPORATION
    Inventors: Toru Tazawa, Hiroshi Fujiwara, Masaru Nishizono
  • Publication number: 20110031906
    Abstract: A motor driving device according to the present invention includes: a serial communication unit that conducts communication through a serial communication bus, the serial communication bus including a serial data line through which serial data is transmitted and a clock line through which a clock signal is transmitted; and a drive control unit that controls a driving operation of a motor. The motor driving device is configured such that a clock signal received from the serial communication bus is used as a reference clock signal of the drive control unit.
    Type: Application
    Filed: March 10, 2009
    Publication date: February 10, 2011
    Applicant: Panasonic Corporation
    Inventors: Masahiro Yasohara, Tomohiro Inoue, Kenji Sugiura, Toru Tazawa, Kenichi Kishimoto
  • Publication number: 20110029137
    Abstract: A motor device comprising a motor, and a drive control circuit for driving and controlling the motor, in which the drive control circuit includes a control unit for generating a control signal for controlling the rotation of the motor, a drive unit for driving the motor on the basis of the control signal, and a communication unit for making serial communications via a serial communication bus for transmitting serial data. This communication unit has an address generating function for generating and setting addresses.
    Type: Application
    Filed: April 6, 2009
    Publication date: February 3, 2011
    Applicant: Panasonic Corporation
    Inventors: Masahiro Yasohara, Tomohiro Inoue, Kenji Sugiura, Toru Tazawa, Kenichi Kishimoto
  • Publication number: 20100333010
    Abstract: An evaluation index selection section in which any evaluation index is selected from a plurality of evaluation indices of the control characteristics in the motor control system and which outputs selection information indicating the selected evaluation index; a relational data extraction section for extracting data related to the selected evaluation index from a data group of the motor control system based on the selection information; an evaluation value calculation section for calculating an evaluation value of the evaluation index based on the extracted data; and a display control section for displaying the calculated evaluation value on a display are included.
    Type: Application
    Filed: January 27, 2009
    Publication date: December 30, 2010
    Applicant: Panasonic Corporation
    Inventors: Yukihiro Yamaichi, Toru Tazawa, Ken'ichi Suzuki
  • Patent number: 7843159
    Abstract: A motor controller includes: a notch filter arranged inside a control system; an oscillation frequency estimating section which estimates an oscillation frequency component in a motor; and a notch control section which controls a notch filter so as to change a notch frequency and a notch width. The notch control section changes a frequency between an oscillation frequency and a notch frequency set in a notch filter as a new notch frequency, while changing a notch width to a new notch width such that the notch width is larger after the change than before the change.
    Type: Grant
    Filed: June 10, 2008
    Date of Patent: November 30, 2010
    Assignee: Panasonic Corporation
    Inventor: Toru Tazawa
  • Publication number: 20080309279
    Abstract: A motor controller includes: a notch filter arranged inside a control system; an oscillation frequency estimating section which estimates an oscillation frequency component in a motor; and a notch control section which controls a notch filter so as to change a notch frequency and a notch width. The notch control section changes a frequency between an oscillation frequency and a notch frequency set in a notch filter as a new notch frequency, while changing a notch width to a new notch width such that the notch width is larger after the change than before the change.
    Type: Application
    Filed: June 10, 2008
    Publication date: December 18, 2008
    Inventor: Toru TAZAWA
  • Patent number: 6936990
    Abstract: An apparatus and method for controlling an electric motor is disclosed. The apparatus includes an instruction inputting section for transmitting an instruction for an electric motor or a control object coupled to said electric motor and a prefilter section for outputting a follow-up instruction value by acting on the instruction. The prefilter section has a prefilter concurrently having characteristics of lowered gain at a prescribed frequency and frequencies in the vicinity thereof, and characteristics of limiting the gain in a high range. An instruction follow-up controlling section provides a controlling instruction follow-up so that a quantity of a state of said electric motor or control object follows the follow-up instruction value.
    Type: Grant
    Filed: March 27, 2003
    Date of Patent: August 30, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Ichiro Oyama, Tomokuni Iijima, Toru Tazawa, Kazushige Narazaki, Kenichi Suzuki, Masaru Nishizono
  • Patent number: 6879129
    Abstract: In a brushless motor control method and a brushless motor controller in accordance with the present invention, a rotor rotation position detection means detects the time of the intersection of a detected induced voltage and an induced voltage reference value. In addition, a motor speed calculation means calculates the rotation speed of a brushless motor on the basis of the interval of the intersection times detected by the rotor rotation position detection means. Furthermore, a speed control means outputs a duty factor index on the basis of the deviation between the command speed and the rotation speed of the brushless motor. Still further, a switching signal generation means outputs switching signals to groups of switching devices on the basis of the rotation speed and the duty factor index at the time of the intersection.
    Type: Grant
    Filed: March 28, 2002
    Date of Patent: April 12, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toru Tazawa, Kazushige Narazaki, Tomokuni Iijima, Hideo Matsushiro, Subrata Saha
  • Patent number: 6844693
    Abstract: An electric motor position control apparatus in accordance with the present invention has a plurality of sets of control parameters including at least the proportional gain of a position control section and the proportional gain of a speed control section beforehand, wherein set selection and the measurement of the response state of an electric motor to a position command at the time when the electric motor is controlled by using the control parameters of the selected set are carried out sequentially, one preferable set is selected depending on the measured response state, the control parameters of the selected set are set, and the control parameters are changed as a set.
    Type: Grant
    Filed: March 6, 2003
    Date of Patent: January 18, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toru Tazawa, Tomokuni Iijima, Ichiro Oyama, Kazushige Narazaki, Kenichi Suzuki, Yasuyuki Yokouchi
  • Publication number: 20040085035
    Abstract: An electric motor position control apparatus in accordance with the present invention has a plurality of sets of control parameters including at least the proportional gain of a position control section and the proportional gain of a speed control section beforehand, wherein set selection and the measurement of the response state of an electric motor to a position command at the time when the electric motor is controlled by using the control parameters of the selected set are carried out sequentially, one preferable set is selected depending on the measured response state, the control parameters of the selected set are set, and the control parameters are changed as a set.
    Type: Application
    Filed: March 6, 2003
    Publication date: May 6, 2004
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toru Tazawa, Tomokuni Iijima, Ichiro Oyama, Kazushige Narazaki, Kenichi Suzuki, Yasuyuki Yokouchi
  • Publication number: 20030184251
    Abstract: The invention provides a method for controlling an electric motor and an apparatus for controlling the same, which lower vibrations generated due to low rigidity of a control object, secure vibration-suppressing performance without depending on instruction patterns and characteristics of a control object, and achieve high positioning accuracy.
    Type: Application
    Filed: March 27, 2003
    Publication date: October 2, 2003
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Ichiro Oyama, Tomokuni Iijima, Toru Tazawa, Kazushige Narazaki, Kenichi Suzuki, Masaru Nishizono
  • Patent number: 6583593
    Abstract: A method for position-sensorless motor control is provided, wherein a rotor-position estimation current signal is superimposed on the &ggr;-axis direction component of a target current vector representing target currents of stator windings. The period of the current signal is an even multiple of a PWM carrier period and varies at random. The amplitude of the current signal increases with the amplitudes of the target currents. An even number of samples are obtained from the &dgr;-axis direction component of a current vector representing detected currents of the stator windings in each period of the current signal. A discrete Fourier integration of the samples determines the amplitude of a current response to the current signal in the &dgr;-axis direction. The &ggr;-axis direction is corrected so that the current response substantially shrinks to zero in the &dgr;-axis direction.
    Type: Grant
    Filed: October 11, 2001
    Date of Patent: June 24, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tomokuni Iijima, Kazushige Narazaki, Toru Tazawa, Ichiro Oyama, Yukinori Maruyama
  • Patent number: 6512341
    Abstract: The invention provides an motor drive apparatus comprising a detector for detecting a terminal voltage in a non-energized phase and a detector for detecting a DC voltage applied to the main line of an inverter. The rotation of the brushless motor is controlled by specifying the inverter circulating current period from the terminal voltage and the DC voltage and calculating the magnetic pole position of the rotor from the terminal voltage after the end of the inverter circulating current period and a waveform of the terminal voltage predetermined from the characteristics of the brushless motor. As a result, the brushless motor can be rotated stably throughout a wide revolution range from low to high speeds.
    Type: Grant
    Filed: July 11, 2001
    Date of Patent: January 28, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hideo Matsushiro, Keizo Matsui, Kazushige Narazaki, Toru Tazawa
  • Patent number: 6462491
    Abstract: A position sensorless motor control apparatus is provided that achieves high resolution and high accuracy angle estimation, achieves angle estimation even in the presence of phase voltage saturation, and achieves high accuracy angle estimation even when a back electromotive force constant changes. An angle estimating unit which generates estimated rotor angle comprises: an estimation phase selecting unit for selecting an estimation phase designating the stator winding phase to be used for the generation of the estimated angle; a deviation generating unit for generating, based on the estimated angle and phase voltage value, a deviation relative to a model expressed by a phase voltage equation of the estimation phase; an angle correcting unit for correcting the estimated angle so that the deviation converges to zero; and an estimated coefficient value correcting unit for correcting an estimated coefficient value which is the estimated value of a coefficient in the phase voltage equation.
    Type: Grant
    Filed: January 26, 2000
    Date of Patent: October 8, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tomoyuki Iijima, Kazushige Narazaki, Toru Tazawa, Yukinori Maruyama
  • Publication number: 20020140395
    Abstract: In a brushless motor control method and a brushless motor controller in accordance with the present invention, a rotor rotation position detection means detects the time of the intersection of a detected induced voltage and an induced voltage reference value. In addition, a motor speed calculation means calculates the rotation speed of a brushless motor on the basis of the interval of the intersection times detected by the rotor rotation position detection means. Furthermore, a speed control means outputs a duty factor index on the basis of the deviation between the command speed and the rotation speed of the brushless motor. Still further, a switching signal generation means outputs switching signals to groups of switching devices on the basis of the rotation speed and the duty factor index at the time of the intersection.
    Type: Application
    Filed: March 28, 2002
    Publication date: October 3, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toru Tazawa, Kazushige Narazaki, Tomokuni Iijima, Hideo Matsushiro, Subrata Saha
  • Publication number: 20020113569
    Abstract: A method and an apparatus for position-sensorless motor control are provided, wherein an undesired sound is reduced and the S/N ratio in a detection of a current response to a rotor-position estimation signal increases without control delay, in contrast to the prior art, especially when a rotor is at a stop or slowly revolves. In the position-sensorless motor control method according to the invention, a rotor-position estimation current signal is superimposed on the &ggr;-axis direction component of a target current vector, which represents target currents of stator windings. The period of the rotor-position estimation current signal is an even multiple of a PWM carrier period, and varies at random. Furthermore, the amplitude thereof increases along with increasing of the amplitudes of the target currents.
    Type: Application
    Filed: October 11, 2001
    Publication date: August 22, 2002
    Applicant: Matsushita Industrial Co., Ltd.
    Inventors: Tomkuni Iijima, Kazuhige Narazaki, Toru Tazawa, Ichiro Oyama, Yukinori Maruyama
  • Publication number: 20020030462
    Abstract: The invention provides an motor drive apparatus comprising a detector for detecting a terminal voltage in a non-energized phase and a detector for detecting a DC voltage applied to the main line of an inverter. The rotation of the brushless motor is controlled by specifying the inverter circulating current period from the terminal voltage and the DC voltage and calculating the magnetic pole position of the rotor from the terminal voltage after the end of the inverter circulating current period and a waveform of the terminal voltage predetermined from the characteristics of the brushless motor. As a result, the brushless motor can be rotated stably throughout a wide revolution range from low to high speeds.
    Type: Application
    Filed: July 11, 2001
    Publication date: March 14, 2002
    Inventors: Hideo Matsushiro, Keizo Matsui, Kazushige Narazaki, Toru Tazawa
  • Patent number: 6163912
    Abstract: A torque current component and an exciting current component of primary AC currents which are supplied to a stator of a three-phase induction motor are commanded independently of each other in accordance with a command rotational angular velocity and a rotational angular velocity of the three-phase induction motor rotating an agitator, and the rotational angular velocity of the three-phase induction motor is controlled by changing the magnitude and frequency of each of the primary AC currents. Furthermore, a test operation is carried out by giving the command angular velocity so as to make constant the angular velocity of the motor, and the laundry amount is estimated corresponding to an output torque of the motor in the test operation.
    Type: Grant
    Filed: August 24, 1998
    Date of Patent: December 26, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Sadahiro Matsuura, Shigeru Satou, Toru Tazawa, Katsuyuki Nagai, Yoshiaki Igarashi