Patents by Inventor Yu Yonezawa

Yu Yonezawa 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: 20190097525
    Abstract: A power-supply apparatus includes a power-supply circuit to which an input voltage and an input current are input, to include a switching element to be controlled by a control signal so as to generate an output voltage and an output current, a memory, and a processor coupled to the memory and the processor to calculate a first duty ratio of the control signal so that the output voltage approaches a target voltage, calculate a second duty ratio of the control signal for the switching element, based on the input voltage, the input current, the output voltage, and the output current, detect deterioration of the power-supply circuit, based on the first duty ratio and the second duty ratio, generate the control signal of the first duty ratio when the power-supply circuit has not deteriorated, and generate the control signal for stopping the power-supply circuit when the power-supply circuit has deteriorated.
    Type: Application
    Filed: September 21, 2018
    Publication date: March 28, 2019
    Applicant: FUJITSU LIMITED
    Inventors: Hiroshi Nakao, Yu Yonezawa, YOSHIYASU NAKASHIMA
  • Publication number: 20190006070
    Abstract: A composite magnetic material includes a needle-like powder and a spherical powder. The needle-like powder includes a soft magnetic material and has an average minor-axis length of 100 nm or less and an average aspect ratio of 3.0 or more and 10.0 or less. The spherical powder includes a soft magnetic material and has an average major-axis length of 100 nm or less and an average aspect ratio of less than 3.0.
    Type: Application
    Filed: June 13, 2018
    Publication date: January 3, 2019
    Applicant: TDK CORPORATION
    Inventors: Yu YONEZAWA, Yoshihiro SHINKAI
  • Publication number: 20180329394
    Abstract: A rapid control prototyping system includes a power supply circuit, a control circuit coupled to the power supply circuit by a plurality of wirings and controls the power supply circuit, the control circuit including a delay amount measuring circuit that output pulses to the power supply circuit by the plurality of wirings and counts reflected pulses by an input of the power supply circuit, a processor that calculates a delay amount of each of the plurality of wirings according to count value of reflected pulses, calculates an offset amount which is a difference between a maximum value of the calculated delay amounts, and delays control signals of the power supply circuit by the offset amount in accordance with each of the plurality of wirings when the control circuit controlling the power supply circuit.
    Type: Application
    Filed: May 3, 2018
    Publication date: November 15, 2018
    Applicant: FUJITSU LIMITED
    Inventors: Atsushi Manabe, Yu Yonezawa
  • Publication number: 20180247746
    Abstract: Provided is a soft magnetic alloy including Fe, as a main component, and including B. Among 80000 pieces of a grid having 1 nm×1 nm×1 nm in a continuous measurement range of the soft magnetic alloy, 4000 pieces of the grid from lower Fe content shows B content variation (?B) of 2.8 or more, and an amorphization ratio X of the soft magnetic alloy of 85% or more.
    Type: Application
    Filed: February 26, 2018
    Publication date: August 30, 2018
    Applicant: TDK CORPORATION
    Inventors: Kazuhiro YOSHIDOME, Hiroyuki MATSUMOTO, Kenji HORINO, Akito HASEGAWA, Yu YONEZAWA, Syota GOTO, Seigo TOKORO
  • Publication number: 20180247744
    Abstract: Provided is a soft magnetic alloy including Fe as a main component, in which a slope of an approximate straight line, plotted between cumulative frequencies of 20 to 80% on Fe content in each grid of 80000 grids or more, each of which has 1 nm×1 nm×1 nm, is ?0.1 to ?0.4, provided that Fe content (atom %) of each grid is Y axis, and the cumulative frequencies (%) obtained in descending order of Fe content in each grid is X axis, and an amorphization ratio X is 85% or more.
    Type: Application
    Filed: February 26, 2018
    Publication date: August 30, 2018
    Applicant: TDK CORPORATION
    Inventors: Kazuhiro YOSHIDOME, Hiroyuki MATSUMOTO, Kenji HORINO, Akito HASEGAWA, Yu YONEZAWA, Syota GOTO, Seigo TOKORO
  • Publication number: 20180247745
    Abstract: Provided is a soft magnetic alloy including Fe, as a main component, and including C. the soft magnetic alloy includes an Fe composite network phase having Fe-rich grids connected in a continuous measurement range including 80000 grids, each of which size is 1 nm×1 nm×1 nm. An average of C content ratio of the Fe-poor grids having cumulative frequency of 90% or more from lower C content is 5.0 times or more to an average of C content ratio of the whole soft magnetic alloy.
    Type: Application
    Filed: February 26, 2018
    Publication date: August 30, 2018
    Applicant: TDK CORPORATION
    Inventors: Kazuhiro YOSHIDOME, Hiroyuki MATSUMOTO, Kenji HORINO, Akito HASEGAWA, Yu YONEZAWA, Syota GOTO, Hajime AMANO
  • Patent number: 10014770
    Abstract: A power supply device coupled to a load includes a first switch that switches a current input from an input terminal, a second switch that switches between a ground potential and an output of the first switch, an inductor that establishes a connection between an output terminal and the output of the first switch, a current sensing circuit that senses a peak current value serving as a peak value of a current flowing through the inductor, and a control circuit that controls a first control terminal of the first switch and a second control terminal of the second switch and that calculates a value of an output current flowing through the load, based on an output value of a temporal coefficient circuit coupled to one of a first control signal.
    Type: Grant
    Filed: October 30, 2017
    Date of Patent: July 3, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Yu Yonezawa, Yoshiyasu Nakashima
  • Publication number: 20180180643
    Abstract: An analysis method of a composition network topology structure includes obtaining a three-dimensional body for analysis capable of being used for three-dimensional measurement of a concentration distribution of a specific element contained in a sample within a predetermined measurement range. The three-dimensional body for analysis is divided into unit grids composed of a plurality of finer three-dimensional bodies. An amount of the specific element contained in each of the unit grids is obtained. Maximum-point grids respectively having a largest amount of the specific element among adjacent unit grids are obtained. The composition network topology structure of the specific element owned by the sample is quantified in relation to the maximum-point grids contained in the three-dimensional body for analysis.
    Type: Application
    Filed: September 27, 2017
    Publication date: June 28, 2018
    Applicant: TDK CORPORATION
    Inventors: Yu YONEZAWA, Kazuhiro YOSHIDOME, Hideaki YOKOTA, Hiroyuki MATSUMOTO, Syota GOTO, Takehiro GOHARA
  • Patent number: 10008940
    Abstract: A power supply device includes: a memory; and a processor coupled to the memory and the processor configured to: determine a duty ratio of a control signal of a switching element in a power supply circuit so that an output voltage of the power supply circuit approaches a target voltage; compute an acceptable range of a duty ratio based on an output current of the power supply circuit detected by a current detecting circuit; output the duty ratio when the duty ratio is inside the acceptable range; and stop the power supply circuit when the duty ratio is outside the acceptable range.
    Type: Grant
    Filed: October 17, 2016
    Date of Patent: June 26, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Takahiko Sugawara, Yu Yonezawa, Hiroshi Nakao, Yoshiyasu Nakashima
  • Publication number: 20180166988
    Abstract: A power supply device coupled to a load includes a first switch that switches a current input from an input terminal, a second switch that switches between a ground potential and an output of the first switch, an inductor that establishes a connection between an output terminal and the output of the first switch, a current sensing circuit that senses a peak current value serving as a peak value of a current flowing through the inductor, and a control circuit that controls a first control terminal of the first switch and a second control terminal of the second switch and that calculates a value of an output current flowing through the load, based on an output value of a temporal coefficient circuit coupled to one of a first control signal.
    Type: Application
    Filed: October 30, 2017
    Publication date: June 14, 2018
    Applicant: FUJITSU LIMITED
    Inventors: Yu Yonezawa, YOSHIYASU NAKASHIMA
  • Patent number: 9960695
    Abstract: A power supply apparatus includes a trans circuit configured to convert an input voltage into an output voltage by adjusting switching of the input voltage; an output voltage detector configured to detect the output voltage; a compensator configured to generate a control value controlling a duty ratio of the switching such that a value of the detected output voltage coincides with a target value for the output voltage; an input voltage detector configured to detect the input voltage; an estimator configured to estimate an allowed range of the control value in accordance with the target value and a value of the detected input voltage; and an adjuster configured to adjust the control value so as to stop the switching when the control value falls outside the allowed range.
    Type: Grant
    Filed: December 8, 2016
    Date of Patent: May 1, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Yu Yonezawa, Takahiko Sugawara, Yoshiyasu Nakashima
  • Publication number: 20180096766
    Abstract: A soft magnetic alloy includes a main component of Fe. The soft magnetic alloy includes a Fe composition network phase where regions whose Fe content is larger than an average composition of the soft magnetic alloy are linked. The Fe composition network phase contains Fe content maximum points that are locally higher than their surroundings. A virtual-line total distance per 1 ?m3 of the soft magnetic alloy is 10 mm to 25 mm provided that the virtual-line total distance is a sum of virtual lines linking the maximum points adjacent each other. A virtual-line average distance that is an average distance of the virtual lines is 6 nm or more and 12 nm or less.
    Type: Application
    Filed: September 28, 2017
    Publication date: April 5, 2018
    Applicant: TDK CORPORATION
    Inventors: Kazuhiro YOSHIDOME, Hiroyuki MATSUMOTO, Yu YONEZAWA, Syota GOTO, Hideaki YOKOTA, Akito HASEGAWA, Masahito KOEDA, Seigo TOKORO
  • Publication number: 20180096765
    Abstract: A soft magnetic alloy includes a main component of Fe. The soft magnetic alloy includes a Fe composition network phase where regions whose Fe content is larger than an average composition of the soft magnetic alloy are linked. The Fe composition network phase contains Fe content maximum points that are locally higher than their surroundings in 400,000/?m3 or more. A ratio of Fe content maximum points whose coordination number is 1 or more and 5 or less is 80% or more and 100% or less with respect to all of the Fe content maximum points.
    Type: Application
    Filed: September 28, 2017
    Publication date: April 5, 2018
    Applicant: TDK CORPORATION
    Inventors: Kazuhiro YOSHIDOME, Hiroyuki MATSUMOTO, Yu YONEZAWA, Syota GOTO, Hideaki YOKOTA, Akito HASEGAWA, Masahito KOEDA, Seigo TOKORO
  • Publication number: 20180068787
    Abstract: An inductor apparatus includes: a substrate including an electrical insulation property and a non-magnetic material; and a plurality of inductors disposed in the substrate so as to extend from a first surface of the substrate to a second surface of the substrate, each of the plurality of inductors including: an inductor conductive part that has an electrical conductivity and extends in a thickness direction of the substrate; and a magnetic layer that covers a side of the inductor conductive part and include a relative permeability and a soft magnetic material.
    Type: Application
    Filed: October 27, 2017
    Publication date: March 8, 2018
    Applicant: FUJITSU LIMITED
    Inventors: Hiroshi NAKAO, Yu Yonezawa, Takahiko Sugawara, Yoshiyasu Nakashima, Yoshikatsu Ishizuki, Shinya Sasaki, Shinya Iijima
  • Patent number: 9893629
    Abstract: A control method for a switching power supply circuit, the control method causing a processor to execute a process, the process includes: calculating a differential value between an output voltage of the switching power supply circuit and a target voltage; multiplying the differential value by a first coefficient to calculate a correction value; correcting a first detection value of an output current of the switching power supply circuit, which is detected by a current transformer circuit, based on the correction value, to generate a second detection value; comparing the second detection value with a threshold current value to determine whether or not an overcurrent has occurred; and reducing, when it is determined that the overcurrent has occurred, the output voltage of the switching power supply circuit.
    Type: Grant
    Filed: September 23, 2016
    Date of Patent: February 13, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Yu Yonezawa, Tomotake Sasaki, Hisato Hosoyama, Yoshiyasu Nakashima
  • Patent number: 9887635
    Abstract: A double-ended forward converter includes: a first switching element and a second switching element that are coupled to a primary side of a transformer; a pulse generation circuit that generates a pulse signal for controlling the first and second switching elements; an isolation transformer that converts the pulse signal into an alternating-current signal; a rectifier circuit that rectifies the alternating-current signal and generate gate voltages of the first and second switching elements; a driver circuit that includes a third switching element which drives gates of the first and second switching elements, a voltage generated on a secondary side of the isolation transformer being input to a gate of the third switching element; and a minus bias generation circuit that generates a source voltage of the third switching, based on a change in the voltage generated on the secondary side of the isolation transformer.
    Type: Grant
    Filed: September 3, 2015
    Date of Patent: February 6, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Yu Yonezawa, Yoshiyasu Nakashima
  • Publication number: 20180025822
    Abstract: A soft magnetic metal dust core including a soft magnetic metal powder and a nonmagnetic material, in which when observing a field of view including “n”, a natural number of 50 or more, particles of the soft magnetic metal powder on a grinded smooth cross section of the dust core, the soft magnetic metal powder is coated by the nonmagnetic material, and a number of an opposing part P is n/2 or more, in which the opposing part P is a part where a length L is 10 ?m or more, and the length L is a continuous length where a distance between particles of the soft magnetic metal powder is 400 nm or less, is provided. The soft magnetic metal dust core is superior in DC superimposing characteristic.
    Type: Application
    Filed: July 21, 2017
    Publication date: January 25, 2018
    Applicant: TDK CORPORATION
    Inventors: Yu YONEZAWA, Tomofumi KURODA, Yusuke TANIGUCHI
  • Publication number: 20170366094
    Abstract: A power supply apparatus includes a DC-DC converter configured to convert an input voltage into an output voltage in accordance with a duty cycle which is decided by a difference of a third signal, a first photo coupler configured to output a first signal corresponding to the output voltage, a converter configured to convert the output voltage into a digital signal, and a second photo coupler configured to output a second signal corresponding to the digital signal, a memory, and a processor coupled to the memory and configured to calculate a third signal on the basis of the difference between the first signal and the second signal, and control the DC-DC converter so that the third signal is to be zero.
    Type: Application
    Filed: June 2, 2017
    Publication date: December 21, 2017
    Applicant: FUJITSU LIMITED
    Inventors: Takahiko Sugawara, Hiroshi Nakao, Yu Yonezawa, Yoshiyasu Nakashima
  • Patent number: 9837208
    Abstract: An inductor apparatus includes: a substrate including an electrical insulation property and a non-magnetic material; and a plurality of inductors disposed in the substrate so as to extend from a first surface of the substrate to a second surface of the substrate, each of the plurality of inductors including: an inductor conductive part that has an electrical conductivity and extends in a thickness direction of the substrate; and a magnetic layer that covers a side of the inductor conductive part and include a relative permeability and a soft magnetic material.
    Type: Grant
    Filed: November 13, 2014
    Date of Patent: December 5, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Hiroshi Nakao, Yu Yonezawa, Takahiko Sugawara, Yoshiyasu Nakashima, Yoshikatsu Ishizuki, Shinya Sasaki, Shinya Iijima
  • Patent number: 9800145
    Abstract: A control device includes a processor that executes a process including generating a driving signal that drives a switching device, so that an output voltage of a converter circuit that performs a step-down conversion on input power by driving the switching device matches a target value, and modifying the target value so that as an output current of the converter circuit becomes lower the output voltage becomes closer to an upper limit value of the output voltage.
    Type: Grant
    Filed: May 12, 2015
    Date of Patent: October 24, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Tomotake Sasaki, Yu Yonezawa, Junji Kaneko, Yoshiyasu Nakashima