Patents by Inventor Kazumichi Yoshida

Kazumichi Yoshida 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: 11990856
    Abstract: A rotation detector includes a motor, a current detector and a hardware processor. The motor includes coils of two or more phases and a rotor. The current detector detects currents flowing in coils of at least two phases among the coils of two or more phases. The hardware processor estimates an initial position of the rotor based on current values of the currents detected by the current detector to start the motor, controls an energization pattern on the phases to rotate and start the motor based on the estimated initial position, and determines whether the rotor stops or is rotating before completing the estimation of the initial position.
    Type: Grant
    Filed: June 30, 2022
    Date of Patent: May 21, 2024
    Assignee: KONICA MINOLTA, INC.
    Inventors: Yuta Tachibana, Hiroyuki Yoshikawa, Kazumichi Yoshida, Satoshi Miyajima, Kouei Cho
  • Publication number: 20240036503
    Abstract: [Problem] To provide a stiffness measuring device capable of highly accurately measuring the stiffness of a recording material such as a sheet, and an image forming system equipped with the stiffness measuring device. [Solution] A stiffness measuring device includes a holding portion that holds a recording material so that a recording surface of the recording material is substantially parallel to a vertical direction, a pressing portion, and a stiffness acquiring section. The pressing portion presses a measurement point located on a lower side in the vertical direction than the portion of the recording material held by the holding portion. The stiffness acquiring section measure a reaction force obtained when the measurement point is pressed by the pressing portion and acquires the measured reaction force as the stiffness of the recording material.
    Type: Application
    Filed: July 11, 2023
    Publication date: February 1, 2024
    Applicant: KONICA MINOLTA, INC.
    Inventors: Yasuo KOYANAGI, Kazumichi YOSHIDA, Yoshihito SASAMOTO, Kazutoshi YOSHIMURA
  • Publication number: 20230228575
    Abstract: A water area object detection system includes an imager to capture an image around a hull, and a controller configured or programmed to perform a control to detect a feature point corresponding to an object in the image together with a distance to the feature point based on the image captured by the imager to create a water area map in which an object presence range including a likelihood that the object is present is set around the feature point. The controller is configured or programmed to reduce the object presence range as the distance from the imager to the feature point decreases, and set a size of the object presence range to a lower limit when the distance from the imager to the feature point is equal to or less than a predetermined distance.
    Type: Application
    Filed: January 4, 2023
    Publication date: July 20, 2023
    Inventor: Kazumichi YOSHIDA
  • Publication number: 20230008381
    Abstract: A rotation detector includes a motor, a current detector and a hardware processor. The motor includes coils of two or more phases and a rotor. The current detector detects currents flowing in coils of at least two phases among the coils of two or more phases. The hardware processor estimates an initial position of the rotor based on current values of the currents detected by the current detector to start the motor, controls an energization pattern on the phases to rotate and start the motor based on the estimated initial position, and determines whether the rotor stops or is rotating before completing the estimation of the initial position.
    Type: Application
    Filed: June 30, 2022
    Publication date: January 12, 2023
    Applicant: Konica Minolta, Inc.
    Inventors: Yuta TACHIBANA, Hiroyuki YOSHIKAWA, Kazumichi YOSHIDA, Satoshi MIYAJIMA, Kouei CHO
  • Patent number: 11233471
    Abstract: A control circuit of a motor control device estimates an initial magnetic pole position of a rotor using an inductive sensing scheme. When estimating the initial magnetic pole position, a drive circuit applies a voltage to a stator winding at each of L electrical angles (L?5) while changing the L electrical angles. An absolute value of an electrical angle difference of the voltage applied to the stator winding between an i-th time (2?i?L) and an i?1st time is 180?360/L degrees or more and 180+360/L degrees or less. An absolute value of an electrical angle difference of the voltage applied to the stator winding between a 1st time for initial position estimation and a last time before starting initial position estimation is 180?360/L degrees or more and 180+360/L degrees or less.
    Type: Grant
    Filed: January 8, 2020
    Date of Patent: January 25, 2022
    Assignee: KONICA MINOLTA, INC.
    Inventors: Daichi Suzuki, Yuji Kobayashi, Kazumichi Yoshida, Harumitsu Fujimori, Yuta Tachibana, Hiroyuki Yoshikawa
  • Patent number: 11223309
    Abstract: In a motor control device that controls a sensorless-type motor, a controller estimates an initial magnetic pole position of a rotor of a motor by an inductive sensing scheme while sequentially setting a plurality of energization angles. At each of the set energization angles, the controller converts peak values of currents flowing through a plurality of phases of a stator winding into a first current component having an electrical angle that is equal to a corresponding one of the set energization angles and a second current component that is different in electrical angle by 90 degrees from the first current component, to correct the first current component based on the second current component. The controller estimates the initial magnetic pole position of the rotor based on the corrected first current component that is obtained at each of the set energization angles.
    Type: Grant
    Filed: February 18, 2020
    Date of Patent: January 11, 2022
    Assignee: KONICA MINOLTA, INC.
    Inventors: Hiroyuki Yoshikawa, Yuta Tachibana, Yuji Kobayashi, Kazumichi Yoshida, Daichi Suzuki, Harumitsu Fujimori
  • Patent number: 11218101
    Abstract: In a motor control device in one embodiment, an initial position estimation unit estimates an initial position of a magnetic pole of a rotor of a motor in an inductive sensing scheme. At each of energization angles, the initial position estimation unit multiplies a ?-axis current component I? corresponding to a peak value of a current flowing through a stator winding by each of a cosine value and a sine value of a correction angle obtained by correcting each of the energization angles. The initial position estimation unit estimates the initial position of the magnetic pole of the rotor based on a ratio between an integrated value of a multiplication result about the cosine value and an integrated value of a multiplication result about the sine value.
    Type: Grant
    Filed: March 11, 2020
    Date of Patent: January 4, 2022
    Assignee: KONICA MINOLTA, INC.
    Inventors: Yuta Tachibana, Hiroyuki Yoshikawa, Yuji Kobayashi, Kazumichi Yoshida, Daichi Suzuki, Harumitsu Fujimori
  • Publication number: 20200295688
    Abstract: In a motor control device that controls a sensorless-type motor, a controller estimates an initial magnetic pole position of a rotor of a motor by an inductive sensing scheme while sequentially setting a plurality of energization angles. At each of the set energization angles, the controller converts peak values of currents flowing through a plurality of phases of a stator winding into a first current component having an electrical angle that is equal to a corresponding one of the set energization angles and a second current component that is different in electrical angle by 90 degrees from the first current component, to correct the first current component based on the second current component. The controller estimates the initial magnetic pole position of the rotor based on the corrected first current component that is obtained at each of the set energization angles.
    Type: Application
    Filed: February 18, 2020
    Publication date: September 17, 2020
    Applicant: KONICA MINOLTA, INC.
    Inventors: Hiroyuki YOSHIKAWA, Yuta TACHIBANA, Yuji KOBAYASHI, Kazumichi YOSHIDA, Daichi SUZUKI, Harumitsu FUJIMORI
  • Publication number: 20200295689
    Abstract: In a motor control device in one embodiment, an initial position estimation unit estimates an initial position of a magnetic pole of a rotor of a motor in an inductive sensing scheme. At each of energization angles, the initial position estimation unit multiplies a ?-axis current component I? corresponding to a peak value of a current flowing through a stator winding by each of a cosine value and a sine value of a correction angle obtained by correcting each of the energization angles. The initial position estimation unit estimates the initial position of the magnetic pole of the rotor based on a ratio between an integrated value of a multiplication result about the cosine value and an integrated value of a multiplication result about the sine value.
    Type: Application
    Filed: March 11, 2020
    Publication date: September 17, 2020
    Inventors: Yuta TACHIBANA, Hiroyuki YOSHIKAWA, Yuji KOBAYASHI, Kazumichi YOSHIDA, Daichi SUZUKI, Harumitsu FUJIMORI
  • Patent number: 10734932
    Abstract: A motor controller that controls a motor in which a rotor using a permanent magnet is rotated by a rotating magnetic field due to a current flowing through a winding: performs hold control that continuously causes a fixed excitation current to flow through the winding to cause a fixed magnetic field for suppressing rotation of the rotor to be generated in a suspension period in which the motor is stopped; performs hold enhancement control that enhances the fixed magnetic field with input of a timing signal defined in advance as a trigger, in the suspension period; and starts rotational excitation control that generates the rotating magnetic field when a rotation start timing arrives.
    Type: Grant
    Filed: April 11, 2019
    Date of Patent: August 4, 2020
    Assignee: Konica Minolta, Inc.
    Inventors: Harumitsu Fujimori, Yuji Kobayashi, Kazumichi Yoshida
  • Publication number: 20200235683
    Abstract: A control circuit of a motor control device estimates an initial magnetic pole position of a rotor using an inductive sensing scheme. When estimating the initial magnetic pole position, a drive circuit applies a voltage to a stator winding at each of L electrical angles (L?5) while changing the L electrical angles. An absolute value of an electrical angle difference of the voltage applied to the stator winding between an i-th time (2?i?L) and an i?1st time is 180?360/L degrees or more and 180+360/L degrees or less. An absolute value of an electrical angle difference of the voltage applied to the stator winding between a 1st time for initial position estimation and a last time before starting initial position estimation is 180?360/L degrees or more and 180+360/L degrees or less.
    Type: Application
    Filed: January 8, 2020
    Publication date: July 23, 2020
    Applicant: KONICA MINOLTA, INC.
    Inventors: Daichi SUZUKI, Yuji KOBAYASHI, Kazumichi YOSHIDA, Harumitsu FUJIMORI, Yuta TACHIBANA, Hiroyuki YOSHIKAWA
  • Publication number: 20190341866
    Abstract: A motor controller that controls a motor in which a rotor using a permanent magnet is rotated by a rotating magnetic field due to a current flowing through a winding: performs hold control that continuously causes a fixed excitation current to flow through the winding to cause a fixed magnetic field for suppressing rotation of the rotor to be generated in a suspension period in which the motor is stopped; performs hold enhancement control that enhances the fixed magnetic field with input of a timing signal defined in advance as a trigger, in the suspension period; and starts rotational excitation control that generates the rotating magnetic field when a rotation start timing arrives.
    Type: Application
    Filed: April 11, 2019
    Publication date: November 7, 2019
    Applicant: KONICA MINOLTA, INC.
    Inventors: Harumitsu Fujimori, Yuji Kobayashi, Kazumichi Yoshida
  • Publication number: 20190068099
    Abstract: A motor controller for controlling a brushless DC motor is provided. The motor controller includes a vector control unit configured to perform a sensorless vector control on the brushless DC motor in accordance with an input command value; a storage portion configured to store time-series control target values so that an amount of rotation angle of the brushless DC motor transitions in a same manner as an expected pattern; and a command portion configured to input, to the vector control unit, the control target values serially as the command value.
    Type: Application
    Filed: August 22, 2018
    Publication date: February 28, 2019
    Applicant: KONICA MINOLTA, INC.
    Inventors: Kazumichi Yoshida, Yuji Kobayashi, Harumitsu Fujimori
  • Publication number: 20180175751
    Abstract: A controller for a permanent magnet synchronous motor having a rotor using a permanent magnet is provided. The rotor rotates by a rotating magnetic field caused by a current flowing through an armature. The controller starts a deceleration control of reducing a rotational speed of the rotor when a stop command is inputted in a state where the rotor rotates at a predetermined rotational speed; and performs a fixed excitation control when the rotational speed is reduced to a set speed. The fixed excitation control includes setting a current for causing a magnetic field vector for stopping the rotor at a target position in accordance with an amount of rotation of the rotor since the deceleration control has started and passing the current through the armature.
    Type: Application
    Filed: December 13, 2017
    Publication date: June 21, 2018
    Applicant: Konica Minolta, Inc.
    Inventors: Kazumichi Yoshida, Katsuhide Sakai, Tomonobu Tamura, Hitoshi Asano, Harumitsu Fujimori
  • Publication number: 20180076750
    Abstract: A controller for a permanent magnet synchronous motor having a rotor using a permanent magnet includes a drive portion configured to apply a current to a winding to drive the rotor; an estimating portion configured to estimate a position of magnetic pole of the rotor; and a control unit configured to control the drive portion to cause the rotating magnetic field based on the estimated position of magnetic pole and to control the drive portion to stop the rotor in response to a stop command inputted. The control unit controls, as the control to stop the rotor, the drive portion to determine a current for generating a magnetic field vector which draws the position of magnetic pole of the rotor to a stop position to stop the rotor based on a latest estimated position of magnetic pole, and to keep applying the current determined to the winding.
    Type: Application
    Filed: August 22, 2017
    Publication date: March 15, 2018
    Applicant: KONICA MINOLTA, INC.
    Inventors: Kazumichi YOSHIDA, Katsuhide SAKAI, Tomonobu TAMURA, Hitoshi ASANO, Harumitsu FUJIMORI
  • Patent number: 4113441
    Abstract: A steam reactor comprises a pressure shell having inlet and outlet nozzles for each of a process gas and a heating gas, a plurality of metal catalyst tubes packed with a catalyst and located substantially vertically within the pressure shell, one and of each of the catalyst tubes being connected to a pipe and the other end being communicated with the inlet nozzle of the process gas; and a riser pipe located substantially vertically within the pressure shell, one end of the riser pipe being connected to the pipes and the other end being terminated in the outlet nozzle of the process gas. A support member is provided on the pressure shell to support the catalyst tubes and the riser pipe. The plurality of pipes which connect the catalyst tubes and the riser pipe have a diameter which is smaller than that of the catalyst tubes and the riser pipe and a structure capable of taking up the difference in thermal expansion between the catalyst tubes and the riser pipe.
    Type: Grant
    Filed: March 7, 1977
    Date of Patent: September 12, 1978
    Assignee: Director-General Agency of Industrial Science and Technology
    Inventors: Akira Suzuki, Kantaro Nakamura, Tetsuo Maejima, Masaru Kajiura, Toshio Aso, Shoichi Abe, Toshihisa Suzuki, Katsuaki Takemura, Masaya Kuno, Kazumichi Yoshida, Junji Yokokawa, Takeshi Miyasugi, Hiroshi Yagi, Kiyohisa Mukai