Patents by Inventor Naoki Akazawa

Naoki Akazawa 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: 20240177181
    Abstract: A demand prediction device of the present disclosure includes an information acquisition means that acquires deviation information indicating a deviation from an actual demand of a target product and a sales quantity, a correction means that corrects the sales quantity based on the deviation information, and a generation means that generates a demand prediction model based on learning data including the corrected sales quantity.
    Type: Application
    Filed: November 21, 2023
    Publication date: May 30, 2024
    Applicants: NEC Corporation, NEC Solution Innovators, Ltd.
    Inventors: Naoki WASHIZUKA, Kyohko AKAZAWA
  • Publication number: 20240177182
    Abstract: A demand prediction device of the present disclosure includes a model acquisition means that acquires a single article prediction model that predicts a demand of a target product and a category prediction model that predicts a demand of a category including the target product, a calculation means that calculates accuracy of demand prediction of the target product in the single article prediction model and the category prediction model, and an adoption means that adopts any one of the single article prediction model and the category prediction model based on the accuracy.
    Type: Application
    Filed: November 21, 2023
    Publication date: May 30, 2024
    Applicants: NEC CORPORATION, NEC SOLUTION INNOVATORS, LTD.
    Inventors: Naoki WASHIZUKA, Kyohko Akazawa
  • Patent number: 6456508
    Abstract: A drive apparatus for a vibrating-type compressor includes a DC power source as well as an inverter including switching elements. The inverter is adapted to convert direct time to alternating current through alternating switching of the switching elements. An inverter control unit is provided for controlling the alternating current supplied from the inverter to the vibrating type compressor. A DC power supply comprises a first power supply including a DC/DC converter. A second power supply is provided including an AC/DC converter. A diode OR circuit is connected to the first and second power supplies. A further circuit is provided which, upon detection of a voltage output from the second power supply, operates to stop the output of the first power supply via a DC/DC converter control unit for controlling the DC/DC converter.
    Type: Grant
    Filed: December 18, 2000
    Date of Patent: September 24, 2002
    Assignee: Sawafuji Electric Co., Ltd.
    Inventors: Masao Namai, Naoki Akazawa
  • Patent number: 6171063
    Abstract: A control circuit for vibrating compressors for converting d-c voltage into a-c voltage to supply a-c voltage to a vibrating compressor (1) comprising a MOS-FET transistor (2) for driving the vibrating compressor (1), a timer IC for generating pulses to switch the MOS-FET transistor (2), a timer forced operation circuit for forcibly reversing the output of the timer IC at a timing at which a counter-electromotive voltage generated by the vibrating compressor (1) during the OFF period of the MOS-FET transistor (2) is restored in the vicinity of 0 volts, a driver for driving the MOS-FET transistor (2) based on the output of the timer IC, and a pulse width changing circuit (9) for detecting an input voltage input into the vibrating compressor (1) and lowering the input voltage to the vibrating compressor (1) by changing the pulse width of output pulses of the timer IC when the input voltage is higher than a predetermined voltage.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: January 9, 2001
    Assignee: Sawafuji Electric Co., Ltd.
    Inventors: Masao Namai, Naoki Akazawa
  • Patent number: 5742492
    Abstract: In a method of driving vibrating compressors having such a construction that a-c voltage is fed to a vibrating compressor by converting d-c voltage into a-c voltage with two MOS-FETs, the two MOS-FETs as switching elements are driven to convert d-c voltage into a-c voltage by changing the ON time of each of the MOS-FETs corresponding to suction and compression strokes in one cycle of the vibrating compressor to improve the operating efficiency of the vibrating compressor. To this end, suction and compression time in one cycle of the vibrating compressor is changed by means of a timer IC.
    Type: Grant
    Filed: August 27, 1996
    Date of Patent: April 21, 1998
    Assignee: Sawafuji Electric Co., Ltd.
    Inventors: Naoki Akazawa, Masao Namai
  • Patent number: 5658132
    Abstract: A power supply for vibrating compressors having an inverter for converting direct current (d-c) into alternating current (a-c). The power supply includes a d-c power source section for applying d-c voltage to the inverter, a current detecting apparatures for detecting a current flowing in the vibrating compressor, a control section having a frequency following circuit for generating a frequency following the resonance frequency of the vibrating compressor on the basis of a current detected by the current detecting apparatures, and an inverter control circuit for controlling the inverter with the frequency generated by the frequency following circuit. The vibrating compressor is driven by an a-c voltage of the frequency agreeing with the resonance frequency of the vibrating compressor.
    Type: Grant
    Filed: October 6, 1994
    Date of Patent: August 19, 1997
    Assignee: Sawafuji Electric Co., Ltd.
    Inventors: Naoki Akazawa, Kazuyuki Ogiwara
  • Patent number: 5656896
    Abstract: A power supply for vibrating compressors comprises a voltage booster circuit portion having voltage changing means for boosting the DC voltage of a commercially available battery and changing the boosted voltage, and an AC voltage generating circuit portion for supplying the boosted DC voltage to the vibrating compressor. The AC voltage generating circuit portion comprises a MOSFET or bipolar transistor for driving a vibrating compressor, a timer IC for generating pulses to cause the MOSFET or bipolar transistor to switch, a forced operation circuit for detecting a timing at which a counter electromotive force generated by the vibrating compressor during the OFF period of the MOSFET or bipolar transistor is recovered to the neighborhood of 0 volts and forcibly reversing the output of the timer IC, and a driver for driving the MOSFET based on the output of the timer IC or a base-current supply circuit for controlling the bipolar transistor.
    Type: Grant
    Filed: February 1, 1996
    Date of Patent: August 12, 1997
    Assignee: Sawafuji Electric Co., Ltd.
    Inventors: Kazuyuki Ogiwara, Naoki Akazawa
  • Patent number: 5237140
    Abstract: An a-c/d-c microwave oven adapted to be connected to an a-c and/or d-c power source. The oven has an inverter for converting d-c power to a-c power to feed power to a magnetron generating high-frequency energy via a transformer. Input from the d-c and a-c power sources is selectively fed to the magnetron. A first primary winding is fed commercial a-c power. A second primary winding is fed on a-c voltage from the inverter. A secondary winding connecting to the magnetron is wound on the transformer. A predetermined voltage is adjusted in the secondary winding of the transformer by adjusting the frequency of the a-c voltage from the inverter at a higher level than the commercial a-c power, which is fed to the second primary winding.
    Type: Grant
    Filed: May 2, 1991
    Date of Patent: August 17, 1993
    Assignee: Sawafuji Electric Co., Ltd.
    Inventors: Naoki Akazawa, Makoto Gezima
  • Patent number: 4706470
    Abstract: A system and apparatus for controlling the operation of a vibrating compressor using a predetermined frequency corresponding to the load thereof, comprising a first sensor for detecting a temperature of pressure corresponding to the saturated vapor pressure of a refrigerant sucked by a vibrating compressor, a second sensor for detecting a temperature or pressure corresponding to the saturated vapor pressure of the refrigerant compressed and discharged by the compressor, and a control section for generating a drive power of a predetermined frequency based on the temperatures and pressures detected by the first and second sensors, and characterized in that the compressor is driven by a drive power generated by the control section.
    Type: Grant
    Filed: May 14, 1986
    Date of Patent: November 17, 1987
    Assignee: Sawafuji Electric Co., Ltd.
    Inventors: Naoki Akazawa, Kazuhiko Nishi, Naoya Kawakami, Yoshiaki Fujisawa, Noriyoshi Yamada