Patents by Inventor Takafumi NATSUMEDA

Takafumi NATSUMEDA 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: 11825630
    Abstract: A cooling system includes: a local cooler that is positioned near a heat source and evaporates a liquid-phase refrigerant by receiving heat from the heat source; a turbo compressor that compresses a gas-phase refrigerant that absorbed the heat in the local cooler; an outdoor unit that condenses the gas-phase refrigerant supplied from the turbo compressor by heat dissipation; and an expansion valve that depressurizes the refrigerant supplied from the outdoor unit and sends the refrigerant to the local cooler. The refrigerant is a low-pressure refrigerant having a condensing pressure lower than a predetermined value.
    Type: Grant
    Filed: July 9, 2019
    Date of Patent: November 21, 2023
    Assignee: NEC CORPORATION
    Inventors: Takafumi Natsumeda, Minoru Yoshikawa, Masaki Chiba
  • Publication number: 20230023287
    Abstract: A cooling system (100) has a housing (101), a heat exchanger (110) and an air distribution controller (120). The housing (101) including an inlet (102) for receiving air exhausted from the server module and an outlet (103) for providing air to the server module. The heat exchanger (110) is mounted between the inlet (102) and the outlet (103), the heat exchanger (110) is configured that a refrigerant (111) contained in the heat exchanger (110) exchanges heat with air passing through the heat exchanger (110). The heat exchanger (110) accepts variation of the refrigerant liquid level. The air distribution controller (120) is mounted in an inlet side of the heat exchanger (110). The air distribution controller (120) has a movable plate which allows an airflow profile from the inlet to the heat exchanger (110) redirected. The air distribution controller (120) controls the airflow profile depending on the liquid level.
    Type: Application
    Filed: January 16, 2020
    Publication date: January 26, 2023
    Applicant: NEC Corporation
    Inventors: Nilmal Singh RAJPUT, Koichi TODOROKI, Takafumi NATSUMEDA, Mahiro HACHIYA, Minoru YOSHIKAWA
  • Publication number: 20220377944
    Abstract: The present invention provides an attachment for a server rack cooling system having at least one heat exchange condenser, the attachment includes: a pipe extension configured to connect to a portion of the server rack cooling system at which air and refrigerant are able to be transferred into the attachment from the at least one heat exchange condenser; a valve on the pipe extension configured to allow exhaust to the outside through the pipe extension at an open position and to block exhaust to the outside at a closed position; and an sensor disposed at a position inside of the pipe extension between the at least one heat exchange condenser and the valve and configured to provide a detection signal determined by a presence of fluid at the position of the sensor; wherein, the valve is opened and closed based on the detection signal from the sensor.
    Type: Application
    Filed: October 2, 2019
    Publication date: November 24, 2022
    Applicant: NEC Corporation
    Inventors: Nirmal Singh RAJPUT, Masaki CHIBA, Mahiro HACHIYA, Takafumi NATSUMEDA, Yoshinori MIYAMOTO, Minoru YOSHIKAWA
  • Publication number: 20220279682
    Abstract: A cooling system includes: a local cooler that is positioned near a heat source and evaporates a liquid-phase refrigerant by receiving heat from the heat source; a turbo compressor that compresses a gas-phase refrigerant that absorbed the heat in the local cooler; an outdoor unit that condenses the gas-phase refrigerant supplied from the turbo compressor by heat dissipation; and an expansion valve that depressurizes the refrigerant supplied from the outdoor unit and sends the refrigerant to the local cooler. The refrigerant is a low-pressure refrigerant having a condensing pressure lower than a predetermined value.
    Type: Application
    Filed: July 9, 2019
    Publication date: September 1, 2022
    Applicant: NEC Corporation
    Inventors: Takafumi NATSUMEDA, Minoru YOSHIKAWA, Masaki CHIBA
  • Publication number: 20220279684
    Abstract: A cooling system includes: a local cooler that is positioned near a server serving as a heat source and that evaporates a refrigerant by directly receiving heat from the server to generate a gas-phase refrigerant; a compressor that compresses the gas-phase refrigerant; an outdoor unit that condenses the gas-phase refrigerant supplied from the compressor by dissipating heat from the gas-phase refrigerant; an expansion valve that depressurizes the refrigerant supplied from the outdoor unit and sends the refrigerant to the local cooler; a pair of detectors that are respectively provided at an inlet side and an outlet side of the compressor and detect a state of the gas-phase refrigerant supplied from the local cooler; and a proportional control valve and a high-speed on-off valve that are operated based on a refrigerant state ratio calculated from a detection value of the detectors.
    Type: Application
    Filed: July 9, 2019
    Publication date: September 1, 2022
    Applicant: NEC Corporation
    Inventors: Yoshinori MIYAMOTO, Takafumi NATSUMEDA, Minoru YOSHIKAWA
  • Patent number: 11428442
    Abstract: A cooling device includes a first evaporation unit, a second evaporation unit, a first condensation unit, a second condensation unit, common piping, a compressor, an expansion valve, a first valve, and a second valve. The common piping combines liquid-phase refrigerant flowing from the first condensation unit and liquid-phase refrigerant flowing from the second condensation unit. The first valve adjusts the liquid-phase refrigerant amount flowing into the first evaporation unit. The second valve adjusts the liquid-phase refrigerant amount flowing into the second evaporation unit. In addition, the pressure inside the common pipe is greater than the respective pressures inside the first evaporation unit and the second evaporation unit.
    Type: Grant
    Filed: March 19, 2019
    Date of Patent: August 30, 2022
    Assignee: NEC CORPORATION
    Inventors: Hisato Sakuma, Koichi Todoroki, Masaki Chiba, Takafumi Natsumeda, Minoru Yoshikawa
  • Publication number: 20220192057
    Abstract: A local cooler includes: a housing formed into a box shape; a heat exchanger provided along a slope extending upward to a rear portion from a lower position located on the front side of the housing; a first intake/exhaust port provided on a front surface of the housing; a second intake/exhaust port provided on a bottom surface of the housing; third intake/exhaust ports provided at a plurality of locations among side surfaces, upper surface and rear surface of the housing; and a closing plate capable of selectively shielding these intake/exhaust ports.
    Type: Application
    Filed: April 13, 2020
    Publication date: June 16, 2022
    Applicant: NEC Corporation
    Inventors: Koichi TODOROKI, Minoru YOSHIKAWA, Kunihiko ISHIHARA, Masaki CHIBA, Yoshinori MIYAMOTO, Takafumi NATSUMEDA, Nirmal Singh RAJPUT
  • Publication number: 20220170662
    Abstract: An air conditioning control device includes a differential pressure calculation unit that calculates differential pressure between the intake side and the exhaust side of a rack containing at least one server, and a rotational speed control unit that controls the rotational speed of an air conditioning fan on the basis of the differential pressure. The rotational speed control unit increases or decreases the rotational speed of the air conditioning fan depending on the variation of the differential pressure in the event of a change in the rotational speed of the air conditioning fan.
    Type: Application
    Filed: January 23, 2020
    Publication date: June 2, 2022
    Applicant: NEC Corporation
    Inventors: Yoshinori MIYAMOTO, Minora YOSHIKAWA, Nirmal Singh RAJPUT, Takafumi NATSUMEDA
  • Publication number: 20220154988
    Abstract: A liquid separator including a cylindrical closed container in which a refrigerant is stored, a refrigerant inflow pipe that allows the refrigerant to flow into the closed container, and a refrigerant outflow pipe that allows the vapor-phase refrigerant in a space inside the closed container to flow out, in which the refrigerant inflow pipe and the refrigerant outflow pipe are each connected from the upper part of the closed container toward the inside thereof, and the closed container has a short cylindrical shape in which the height is smaller relative to the diameter.
    Type: Application
    Filed: March 6, 2020
    Publication date: May 19, 2022
    Applicant: NEC Corporation
    Inventors: Takafumi NATSUMEDA, Masaki CHIBA, Koichi TODOROKI, Minoru YOSHIKAWA
  • Publication number: 20210368648
    Abstract: To provide a cooling device capable of cooling a heat-generating body using simple configuration, the cooling device comprises two evaporators, two condensers, a compressor and an expansion valve, and is configured so that any one among a first flow path setting, a second flow path setting, a third flow path setting, and a fourth flow path setting can be selected.
    Type: Application
    Filed: January 21, 2019
    Publication date: November 25, 2021
    Applicant: NEC Corporation
    Inventors: Masaki CHIBA, Minoru YOSHIKAWA, Hisato SAKUMA, Takafumi NATSUMEDA
  • Publication number: 20210003327
    Abstract: In order to efficiently distribute a heat medium at a low heat medium pressure, a heat exchange apparatus includes a heat exchange pipe 2 configured to accommodate a heat medium L to be evaporated by heat absorption from a gas to be cooled, the heat exchange pipe being disposed in an inclined state, a supply pipe 1 configured to supply the heat medium L in a liquid-phase state, the supply pipe being placed in a vicinity of a lower part of the heat exchange pipe 2, a discharge pipe 3 configured to receive a heat medium L to be evaporated in the heat exchange pipe 2 and discharged from an upper part of the heat exchange pipe, and a connecting pipe 4 placed, directing downward, between an upper part of the heat exchange pipe 2 and the discharge pipe 3.
    Type: Application
    Filed: March 20, 2019
    Publication date: January 7, 2021
    Applicant: NEC Corporation
    Inventors: Koichi TODOROKI, Minoru YOSHIKAWA, Kunihiko ISHIHARA, Masaki CHIBA, Yoshinori MIYAMOTO, Takafumi NATSUMEDA, Nirmal Singh RAJPUT
  • Publication number: 20200400348
    Abstract: A cooling device 10 comprising a first evaporation unit 11, a second evaporation unit 12, a first condensation unit 21, a second condensation unit 22, common piping CP, a compressor 30, an expansion valve 40, a first valve 71, and a second valve 72. The common piping CP combines liquid-phase refrigerant LP-COO flowing from the first condensation unit 21 and liquid-phase refrigerant LP-COO flowing from the second condensation unit 22. The first valve 71 adjusts the liquid-phase refrigerant amount LP-COO flowing into the first evaporation unit 11. The second valve 72 adjusts the liquid-phase refrigerant amount LP-COO flowing into the second evaporation unit 12. In addition, the pressure P0 inside the common pipe CP is greater than the respective pressures P1 and P2 inside the first evaporation unit 11 and the second evaporation unit 12. Thus, the length of the piping can be shortened.
    Type: Application
    Filed: March 19, 2019
    Publication date: December 24, 2020
    Applicant: NEC Corporation
    Inventors: Hisato SAKUMA, Koichi TODOROKI, Masaki CHIBA, Takafumi NATSUMEDA, Minoru YOSHIKAWA
  • Publication number: 20190145667
    Abstract: Since improving heat exchange between a gas-phase refrigerant and a liquid-phase refrigerant in a refrigeration system could instead result in a reduction in the efficiency of the whole refrigeration system, a heat exchange device (201) of the present invention includes: a refrigerant supply means (210) for supplying a first-temperature liquid-phase refrigerant (R11) and a second-temperature gas-phase refrigerant (R12) in one circulation system; a plurality of heat exchange means (220A, 220B) which are each configured so as to perform heat exchange between the liquid-phase refrigerant and the gas-phase refrigerant; and refrigerant circulation means (231, 232, 242) for circulating the gas-phase refrigerant (R12) in such a manner that the gas-phase refrigerant (R12) flows in parallel in the plurality of heat exchange means, and circulating the liquid-phase refrigerant (R11) in such a manner that the liquid-phase refrigerant (R11) flows in series in the plurality of heat exchange means.
    Type: Application
    Filed: March 23, 2017
    Publication date: May 16, 2019
    Applicant: NEC CORPORATION
    Inventors: Arihiro MATSUNAGA, Minoru YOSHIKAWA, Hisato SAKUMA, Masato YANO, Asuka MATSUBA, Takafumi NATSUMEDA