Patents by Inventor Kenichi Nakazato

Kenichi Nakazato 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).

  • Publication number: 20180299298
    Abstract: A brushless resolver includes a rotor having a one-phase excitation coil and a stator having two-phase detection coils. The rotor is mounted to a shaft of a motor to detect a rotation angle of the motor. An induction coil is located around the shaft. The induction coil is connected to the excitation coil. Electromotive force induced in the induction coil by a change of magnetic flux of the motor, which passes through the shaft, is used as an excitation signal supplied to the excitation coil.
    Type: Application
    Filed: August 29, 2016
    Publication date: October 18, 2018
    Applicants: JAPAN AVIATION ELECTRONICS INDUSTRY, LIMITED, HONDA MOTOR CO., LTD.
    Inventors: Tomoya ANDO, Kenichi NAKAZATO, Manabu YAZAKI
  • Patent number: 9857203
    Abstract: An n-th-harmonic error estimation unit that estimates the error component of an n-th harmonic included in a resolver angle ? and a subtraction unit that subtracts an n-th-harmonic estimated angle error from ? to output the corrected angle ?? are included.
    Type: Grant
    Filed: November 24, 2015
    Date of Patent: January 2, 2018
    Assignee: JAPAN AVIATION ELECTRONICS INDUSTRY, LIMITED
    Inventors: Kenichi Nakazato, Yoshiyuki Kobayashi
  • Publication number: 20170343384
    Abstract: An n-th-harmonic error estimation unit that estimates the error component of an n-th harmonic included in a resolver angle 8 and a subtraction unit that subtracts an n-th-harmonic estimated angle error from ? to output the corrected angle ?? are included.
    Type: Application
    Filed: November 24, 2015
    Publication date: November 30, 2017
    Applicant: JAPAN AVIATION ELECTRONICS INDUSTRY, LIMITED
    Inventors: Kenichi NAKAZATO, Yoshiyuki KOBAYASHI
  • Patent number: 9500500
    Abstract: The number of turns and the winding direction of a cosine-phase coil wound around an i-th tooth and the number of turns and the winding direction of a sine-phase coil wound around the i-th tooth are set according to Tc,i=TSmax cos(ms?i+?2)+T2c cos(me?i+?1) and Ts,i=TSmax sin(ms?i+?2)+T2s cos(me?i+?1), respectively, where TSmax: a first reference number of turns of each of the detecting coils of each phase, T2c: a second reference number of turns of each of the cosine-phase coils, T2s: a second reference number of turns of each of the sine-phase coils, me: a pole pair number in a magnetic flux distribution formed by the exciting coils, ms: a pole pair number in each magnetic flux distribution formed by the detecting coils of each phase, ?1: the phase of the exciting coils, ?2: each phase of the cosine-phase coils and the sine-phase coils, and ?i: a mechanical angle of the i-th tooth.
    Type: Grant
    Filed: April 28, 2015
    Date of Patent: November 22, 2016
    Assignee: JAPAN AVIATION ELECTRONICS INDUSTRY, LIMITED
    Inventors: Hiroki Ookawara, Toshifumi Yoshikawa, Hirokuni Wakui, Kenichi Nakazato, Manabu Yazaki
  • Publication number: 20150345995
    Abstract: The number of turns and the winding direction of a cosine-phase coil wound around an i-th tooth and the number of turns and the winding direction of a sine-phase coil wound around the i-th tooth are set according to Tc,i=TSmax cos(ms?i+?2)+T2c cos(me?i+?1) and Ts,i=TSmax sin(ms?i+?2)+T2s cos(me?i+?1), respectively, where TSmax: a first reference number of turns of each of the detecting coils of each phase, T2c: a second reference number of turns of each of the cosine-phase coils, T2s: a second reference number of turns of each of the sine-phase coils, me: a pole pair number in a magnetic flux distribution formed by the exciting coils, ms: a pole pair number in each magnetic flux distribution formed by the detecting coils of each phase, ?1: the phase of the exciting coils, ?2: each phase of the cosine-phase coils and the sine-phase coils, and ?i: a mechanical angle of the i-th tooth.
    Type: Application
    Filed: April 28, 2015
    Publication date: December 3, 2015
    Applicant: JAPAN AVIATION ELECTRONICS INDUSTRY, LIMITED
    Inventors: Hiroki OOKAWARA, Toshifumi YOSHIKAWA, Hirokuni WAKUI, Kenichi NAKAZATO, Manabu YAZAKI
  • Patent number: 9013132
    Abstract: Two excitation coils (excitation A coil, excitation B coil) and two detection coils (detection A coil, detection B coil) are provided. The excitation A coil and the excitation B coil are excited at frequencies that are different from each other. The number of turns of the detection A coil and the detection B coil are respectively set with two sine waves using the number ms1 and ms2 of pole pairs. The number ms1 and ms2 of pole pairs, the number mx1 and mx2 of pole pairs of the excitation A coil and the excitation B coil, and the number mr of pole pairs of a rotor are set to have a predetermined relationship. A resolver having redundancy can be realized with small number of coils.
    Type: Grant
    Filed: June 21, 2012
    Date of Patent: April 21, 2015
    Assignee: Japan Aviation Electronics Industry, Limited
    Inventor: Kenichi Nakazato
  • Publication number: 20140308609
    Abstract: The invention addresses the problem of providing a positively chargeable toner for nonmagnetic mono-component development systems, which is free from image density reduction, back ground and toner scattering inside the machine that are caused by insufficient electrification and which has excellent toner starvation on black page, without impairing the durability. In the positively chargeable toner for nonmagnetic mono-component development system, which at least comprises a binder resin, a colorant and a charge control agent, a styrene-acrylic resin is used as the binder resin, and the toner comprises: polytetrafluoroethylene fine particles; and inorganic fine particles that have been surface-treated with an amino group-containing treating agent.
    Type: Application
    Filed: June 26, 2014
    Publication date: October 16, 2014
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventor: Kenichi NAKAZATO
  • Patent number: 8491522
    Abstract: A computer controlled electric syringe includes: a piston unit including a piston being configured to press and move a rubber plug of a cartridge by a second end to discharge a medicinal solution from a cartridge through an injection needle; a ball screw having a screw shaft and a nut portion that is screwed into the screw shaft, the screw shaft being loosely inserted into the hollow portion of the piston through the opening, the nut portion being coupled to the piston; a screw shaft supporting portion rotatably supporting the screw shaft of the ball screw; a rotation preventing portion configured to prevent the nut portion of the ball screw from being rotated; and a piston supporting portion supporting the piston to be movable in an axial direction of the screw shaft along with the nut portion by the rotation of the screw shaft.
    Type: Grant
    Filed: May 24, 2010
    Date of Patent: July 23, 2013
    Assignee: Nippon Shika Yakuhin Co., Ltd.
    Inventors: Minoru Takatsuka, Kenichi Nakazato
  • Publication number: 20130060518
    Abstract: Two excitation coils (excitation A coil, excitation B coil) and two detection coils (detection A coil, detection B coil) are provided. The excitation A coil and the excitation B coil are excited at frequencies that are different from each other. The number of turns of the detection A coil and the detection B coil are respectively set with two sine waves using the number ms1 and ms2 of pole pairs. The number ms1 and ms2 of pole pairs, the number mx1 and mx2 of pole pairs of the excitation A coil and the excitation B coil, and the number mr of pole pairs of a rotor are set to have a predetermined relationship. A resolver having redundancy can be realized with small number of coils.
    Type: Application
    Filed: June 21, 2012
    Publication date: March 7, 2013
    Applicant: Japan Aviation Electronics Industry, Limited
    Inventor: Kenichi Nakazato
  • Patent number: 8004434
    Abstract: An RD converter is disclosed that has a first multiplier multiplying a resolver signal S1 by an output of a SIN ROM; a second multiplier multiplying a resolver signal S2 by an output of a COS ROM; a subtractor subtracting an output of the first multiplier from an output of the second multiplier; a synchronous detecting circuit detecting synchronously an output of the subtractor with reference to an excitation signal; a controller controlling an output angle ?? to make an output of the synchronous detecting circuit equal to zero; a correction data part outputting a correction angle ?c for the output angle ??; an adder adding the output angle ?? and the correction angle ?c; the SIN ROM producing a sine value of a result from the adder; and the COS ROM producing a cosine value of the result.
    Type: Grant
    Filed: January 7, 2010
    Date of Patent: August 23, 2011
    Assignee: Japan Aviation Electronics Industry Limited
    Inventors: Kenichi Nakazato, Masayuki Watanabe
  • Patent number: 8004276
    Abstract: A reference signal generation circuit generates a reference signal used in synchronous detection for removing an excitation signal component in an angle calculation section that converts a detection angle ? obtained from two-phase resolver detection signals output from a resolver, to a digital output angle ?. The reference signal generation circuit includes a first multiplier, a second multiplier, and an adder. The first multiplier multiplies one of the resolver detection signals sin ? sin(?t+??) by the sine value sin ? of the digital output angle ? obtained from the angle calculation section. The second multiplier multiplies the other resolver detection signal cos ? sin(?t+??) by the cosine value cos ? of the digital output angle ? obtained from the angle calculation section. The adder adds the output of the first multiplier and the output of the second multiplier to output the sum signal sin(?t+??) as the reference signal.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: August 23, 2011
    Assignee: Japan Aviation Electronics Industry Limited
    Inventors: Hisashi Nishimura, Kenichi Nakazato
  • Publication number: 20110190693
    Abstract: A computer controlled electric syringe includes: a piston unit including a piston being configured to press and move a rubber plug of a cartridge by a second end to discharge a medicinal solution from a cartridge through an injection needle; a ball screw having a screw shaft and a nut portion that is screwed into the screw shaft, the screw shaft being loosely inserted into the hollow portion of the piston through the opening, the nut portion being coupled to the piston; a screw shaft supporting portion rotatably supporting the screw shaft of the ball screw; a rotation preventing portion configured to prevent the nut portion of the ball screw from being rotated; and a piston supporting portion supporting the piston to be movable in an axial direction of the screw shaft along with the nut portion by the rotation of the screw shaft.
    Type: Application
    Filed: May 24, 2010
    Publication date: August 4, 2011
    Applicant: NIPPON SHIKA YAKUHIN KK.
    Inventors: Minoru TAKATSUKA, Kenichi NAKAZATO
  • Patent number: 7973583
    Abstract: An A/B-phase signal generator wherein an up/down count unit 52C counts up by an up-count command or counts down by a down-count command at fixed intervals, an angle comparison unit 51 compares the count result ACNT of up/down count unit 52C with an input rotation angle ? and generates a count request, which is an up-count request or a down-count request, a count request comparison unit 52B compares a previous count request with a next count request and generates an up-count command or a down-count command only when the previous count request and the next count request are both up-count requests or down-count requests, respectively, and an A/B-phase pulse generator 53 receives a least significant bit and a second least significant bit of up/down count unit 52C and generates and outputs an A-phase pulse signal and a B-phase pulse signal.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: July 5, 2011
    Assignee: Japan Aviation Electronics Industry Limited
    Inventors: Hisashi Nishimura, Kenichi Nakazato
  • Patent number: 7859254
    Abstract: Two-phase resolver signals output from a rotation angle detector are squared by first and second squaring circuits. The squared signals are added by an adding circuit. The DC component of the output signal from the adding circuit is removed by a filter. The output signal from the filter is compared with a reference potential by a comparator to generate a rectangular-wave signal. The phase of the rectangular-wave signal is corrected a phase shifter. The frequency of the output signal from the phase shifter is divided by 2 by a frequency dividing circuit in synchronization with an excitation signal supplied to the rotation angle detector to generate a synchronous clock.
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: December 28, 2010
    Assignee: Japan Aviation Electronics Industry Limited
    Inventors: Kenichi Nakazato, Hisashi Nishimura
  • Patent number: 7840364
    Abstract: Potentials at both ends of an exciter coil to which an exciting signal is sent by a push-pull method are compared, and at least one of a short circuit to ground and a short circuit to a power supply of a signal line for the exciting signal is detected based on the duty cycle of a rectangular-wave signal indicating the result of comparison. Alternatively, a predetermined reference potential is compared with a potential of at least one of two phase detection signals before detection, and at least one of a short circuit to the ground and a short circuit to the power supply of a signal line for the at least one of the detection signals is detected based on the duty cycle of a rectangular-wave signal indicating the result of comparison.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: November 23, 2010
    Assignee: Japan Aviation Electronics Industry Limited
    Inventor: Kenichi Nakazato
  • Patent number: 7768431
    Abstract: A band elimination filter 35 that eliminates or reduces a low frequency noise superposed on resolver signals S1 and S2 is provided between a synchronous detection circuit 34 that performs synchronous detection by referring to an excitation signal and a controller 36 that controls a digital angle output ? to make a deviation (sin(???)), which is the output of the synchronous detection circuit, zero.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: August 3, 2010
    Assignee: Japan Aviation Electronics Industry Limited
    Inventors: Kenichi Nakazato, Hisashi Nishimura
  • Publication number: 20100176975
    Abstract: An RD converter is disclosed that has a first multiplier multiplying a resolver signal S1 by an output of a SIN ROM; a second multiplier multiplying a resolver signal S2 by an output of a COS ROM; a subtractor subtracting an output of the first multiplier from an output of the second multiplier; a synchronous detecting circuit detecting synchronously an output of the subtractor with reference to an excitation signal; a controller controlling an output angle ?? to make an output of the synchronous detecting circuit equal to zero; a correction data part outputting a correction angle ?c for the output angle ??; an adder adding the output angle ?? and the correction angle ?c; the SIN ROM producing a sine value of a result from the adder; and the COS ROM producing a cosine value of the result.
    Type: Application
    Filed: January 7, 2010
    Publication date: July 15, 2010
    Applicant: Japan Aviation Electronics Industry Limited
    Inventors: Kenichi Nakazato, Masayuki Watanabe
  • Publication number: 20100001778
    Abstract: An A/B-phase signal generator wherein an up/down count unit 52C counts up by an up-count command or counts down by a down-count command at fixed intervals, an angle comparison unit 51 compares the count result ACNT of up/down count unit 52C with an input rotation angle ? and generates a count request, which is an up-count request or a down-count request, a count request comparison unit 52B compares a previous count request with a next count request and generates an up-count command or a down-count command only when the previous count request and the next count request are both up-count requests or down-count requests, respectively, and an A/B-phase pulse generator 53 receives a least significant bit and a second least significant bit of up/down count unit 52C and generates and outputs an A-phase pulse signal and a B-phase pulse signal.
    Type: Application
    Filed: June 30, 2009
    Publication date: January 7, 2010
    Applicant: Japan Aviation Electronics Industry Limited
    Inventors: Hisashi Nishimura, Kenichi Nakazato
  • Publication number: 20090179634
    Abstract: Two-phase resolver signals output from a rotation angle detector are squared by first and second squaring circuits. The squared signals are added by an adding circuit. The DC component of the output signal from the adding circuit is removed by a filter. The output signal from the filter is compared with a reference potential by a comparator to generate a rectangular-wave signal. The phase of the rectangular-wave signal is corrected a phase shifter. The frequency of the output signal from the phase shifter is divided by 2 by a frequency dividing circuit in synchronization with an excitation signal supplied to the rotation angle detector to generate a synchronous clock.
    Type: Application
    Filed: January 9, 2009
    Publication date: July 16, 2009
    Applicant: Japan Aviation Electronics Industry Limited
    Inventors: Kenichi Nakazato, Hisashi Nishimura
  • Publication number: 20090160687
    Abstract: A band elimination filter 35 that eliminates or reduces a low frequency noise superposed on resolver signals S1 and S2 is provided between a synchronous detection circuit 34 that performs synchronous detection by referring to an excitation signal and a controller 36 that controls a digital angle output ? to make a deviation (sin(???)), which is the output of the synchronous detection circuit, zero.
    Type: Application
    Filed: December 19, 2008
    Publication date: June 25, 2009
    Applicant: Japan Aviation Electronics Industry Limited
    Inventors: Kenichi Nakazato, Hisashi Nishimura