Patents by Inventor Yuusuke OKA

Yuusuke OKA 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: 11047590
    Abstract: An air conditioner, in which a liquid-pressure adjustment expansion valve that decompresses a refrigerant so that the refrigerant flowing through a liquid-refrigerant connection pipe is in a gas-liquid two-phase state is provided in an outdoor liquid-refrigerant pipe that connects a liquid-side end of an outdoor heat exchanger to the liquid-refrigerant connection pipe, properly transports the refrigerant in a two-phase state while suppressing an increase in a discharge temperature of a compressor. A liquid injection pipe that branches part of a refrigerant flowing through an outdoor liquid-refrigerant pipe and feeds the branched refrigerant to a compressor is connected to a portion of the outdoor liquid-refrigerant pipe on a side of an outdoor heat exchanger with respect to a liquid-pressure adjustment expansion valve.
    Type: Grant
    Filed: September 26, 2017
    Date of Patent: June 29, 2021
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro Yamada, Yuusuke Nakagawa, Masahiro Honda, Yuusuke Oka
  • Patent number: 11022354
    Abstract: Noise that is generated from an indoor unit is suppressed when performing two-phase transport of refrigerant by using a liquid-pressure-adjusting expansion valve in an air conditioner including an outdoor unit, a plurality of indoor units each including an indoor heat exchanger, a relay unit that switches the plurality of indoor heat exchangers so that the indoor heat exchangers individually function as an evaporator or radiator for refrigerant, and a liquid-refrigerant connection pipe and a gas-refrigerant connection pipe that connect the outdoor unit and the indoor unit via the relay unit. The relay unit includes a relay expansion valve that further decompresses the refrigerant that has been decompressed by the liquid-pressure-adjusting expansion valve.
    Type: Grant
    Filed: September 26, 2017
    Date of Patent: June 1, 2021
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro Yamada, Yuusuke Nakagawa, Yuusuke Oka, Masahiro Honda
  • Publication number: 20210131706
    Abstract: An air conditioner includes: an outdoor unit; a liquid-refrigerant connection pipe and a gas-refrigerant connection pipe; an indoor unit; a gas-side shutoff valve; a refrigerant sensor; and a controller. The indoor unit is connected to the outdoor unit via the liquid-refrigerant and gas-refrigerant connection pipes, is arranged in an air-conditioning target space, and includes: an indoor heat exchanger that performs heat exchange between a refrigerant circulated between the indoor unit and the outdoor unit via the liquid-refrigerant and gas-refrigerant connection pipes and air sent to the air-conditioning target space; an indoor expansion valve that decompresses the refrigerant; a heat-exchange-side indoor liquid-refrigerant pipe that connects a liquid side of the indoor heat exchanger to the indoor expansion valve; and a connection-side indoor liquid-refrigerant pipe that connects the indoor expansion valve to the liquid-refrigerant connection pipe.
    Type: Application
    Filed: December 22, 2017
    Publication date: May 6, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro Yamada, Masahiro Honda, Yuusuke Oka
  • Patent number: 10976090
    Abstract: An air conditioner includes: liquid-side indoor expansion valves corresponding to a liquid side of respective indoor heat exchangers; and gas-side indoor expansion valves corresponding to a gas side of the respective indoor heat exchangers. In a case where both a heating-operation indoor heat exchanger and a heating-stopped indoor heat exchanger are present, the controller of the air conditioner controls the liquid-side indoor expansion valve and the gas-side indoor expansion valve corresponding to the heating-stopped indoor heat exchanger such that an opening degree of the gas-side indoor expansion valve becomes smaller than an opening degree of the liquid-side indoor expansion valve.
    Type: Grant
    Filed: September 29, 2017
    Date of Patent: April 13, 2021
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro Yamada, Yuusuke Nakagawa, Masahiro Honda, Yuusuke Oka
  • Publication number: 20200318875
    Abstract: A refrigeration apparatus includes: a heat source unit including a compressor for refrigerant and a heat-source-side heat exchanger; utilization units, each of which is connected in parallel to the heat source unit and includes a utilization-side heat exchanger; a refrigerant-flow-path switching unit that includes first gas-side control valves, each of which switches a flow of refrigerant in a corresponding one of the utilization units, and individually switches a flow of refrigerant in each of the utilization units; a first gas-side connection pipe disposed between the heat source unit and each of the first gas-side control valves and through which high-pressure gas refrigerant flows; first gas-side branch pipes, each of which is included in the first gas-side connection pipe and communicates with a corresponding one of the utilization units; and a blocking valve.
    Type: Application
    Filed: September 29, 2017
    Publication date: October 8, 2020
    Inventors: Takuro YAMADA, Yuusuke NAKAGAWA, Yuusuke OKA, Masahiro HONDA
  • Patent number: 10712035
    Abstract: When refrigerant leakage occurs, a controller in an air conditioner performs first shutoff control to open a liquid relay shutoff valve and close an indoor expansion valve and a gas relay shutoff valve on the basis of information from a refrigerant leakage detector.
    Type: Grant
    Filed: November 21, 2019
    Date of Patent: July 14, 2020
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro Yamada, Yuusuke Nakagawa, Yuusuke Oka
  • Patent number: 10670282
    Abstract: To reduce noise coming from an indoor unit in an air conditioning apparatus that has an outdoor unit that has a compressor and an outdoor heat exchanger, the indoor unit that has an indoor heat exchanger, and a liquid refrigerant connection pipe and a gas refrigerant connection pipe that interconnect both units and in which a liquid pressure adjusting expansion valve that reduces a pressure of a refrigerant flowing through the liquid refrigerant connection pipe in such a way that the refrigerant is in a gas-liquid two-phase state is provided in an outdoor liquid refrigerant pipe that interconnects the liquid-side end of the outdoor heat exchanger and the liquid refrigerant connection pipe. An external expansion valve unit having an external expansion valve that further reduces the pressure of the refrigerant whose pressure has been reduced in the liquid pressure adjusting expansion valve is provided in the outdoor liquid refrigerant pipe.
    Type: Grant
    Filed: September 26, 2017
    Date of Patent: June 2, 2020
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro Yamada, Masahiro Honda, Yuusuke Nakagawa, Yuusuke Oka
  • Publication number: 20200088431
    Abstract: When refrigerant leakage occurs, a controller in an air conditioner performs first shutoff control to open a liquid relay shutoff valve and close an indoor expansion valve and a gas relay shutoff valve on the basis of information from a refrigerant leakage detector.
    Type: Application
    Filed: November 21, 2019
    Publication date: March 19, 2020
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Yuusuke NAKAGAWA, Yuusuke OKA
  • Publication number: 20200033036
    Abstract: In a refrigeration apparatus including a refrigerant circuit in which a refrigerant in a gas-liquid two-phase state flows through a liquid-side connection pipe, a refrigerant-amount determining method and a refrigerant-amount determining device capable of grasping an appropriate refrigerant charging amount corresponding to the length of the connection pipe is provided.
    Type: Application
    Filed: September 29, 2017
    Publication date: January 30, 2020
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Yuusuke NAKAGAWA, Masahiro HONDA, Yuusuke OKA, Hiroki SASAYAMA
  • Patent number: 10533764
    Abstract: When refrigerant leakage occurs, a controller in an air conditioner performs first shutoff control to open a liquid relay shutoff valve and close an indoor expansion valve and a gas relay shutoff valve on the basis of information from a refrigerant leakage detector.
    Type: Grant
    Filed: April 16, 2019
    Date of Patent: January 14, 2020
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro Yamada, Yuusuke Nakagawa, Yuusuke Oka
  • Patent number: 10502446
    Abstract: In an air conditioning device (10) to which an outdoor unit (20) and indoor units (40) are connected, when a flow rate of a gaseous refrigerant in a gas main pipe (72a) is lower than a lower limit flow rate in main pipe, an amount of refrigerating machine oil accumulated in the gas main pipe (72a) is calculated. When gas branch pipes (72b) include a gas branch pipe (72b) having a flow rate lower than a lower limit flow rate in branch pipe even though the flow rate of the gaseous refrigerant in the gas main pipe (72a) is higher than the lower limit flow rate in main pipe, an amount of the machine oil accumulated in the gas branch pipe (72b) is calculated. When the amounts are integrated and the integrated value exceeds a set amount, oil collecting operation is performed.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: December 10, 2019
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Ryuuta Ohura, Yuusuke Oka, Junya Minami
  • Publication number: 20190338986
    Abstract: To reduce noise coming from an indoor unit in an air conditioning apparatus that has an outdoor unit that has a compressor and an outdoor heat exchanger, the indoor unit that has an indoor heat exchanger, and a liquid refrigerant connection pipe and a gas refrigerant connection pipe that interconnect both units and in which a liquid pressure adjusting expansion valve that reduces a pressure of a refrigerant flowing through the liquid refrigerant connection pipe in such a way that the refrigerant is in a gas-liquid two-phase state is provided in an outdoor liquid refrigerant pipe that interconnects the liquid-side end of the outdoor heat exchanger and the liquid refrigerant connection pipe. An external expansion valve unit having an external expansion valve that further reduces the pressure of the refrigerant whose pressure has been reduced in the liquid pressure adjusting expansion valve is provided in the outdoor liquid refrigerant pipe.
    Type: Application
    Filed: September 26, 2017
    Publication date: November 7, 2019
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Masahiro HONDA, Yuusuke NAKAGAWA, Yuusuke OKA
  • Publication number: 20190249912
    Abstract: An air conditioner includes: liquid-side indoor expansion valves corresponding to a liquid side of respective indoor heat exchangers; and gas-side indoor expansion valves corresponding to a gas side of the respective indoor heat exchangers. In a case where both a heating-operation indoor heat exchanger and a heating-stopped indoor heat exchanger are present, the controller of the air conditioner controls the liquid-side indoor expansion valve and the gas-side indoor expansion valve corresponding to the heating-stopped indoor heat exchanger such that an opening degree of the gas-side indoor expansion valve becomes smaller than an opening degree of the liquid-side indoor expansion valve.
    Type: Application
    Filed: September 29, 2017
    Publication date: August 15, 2019
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Yuusuke NAKAGAWA, Masahiro HONDA, Yuusuke OKA
  • Publication number: 20190242602
    Abstract: When refrigerant leakage occurs, a controller in an air conditioner performs first shutoff control to open a liquid relay shutoff valve and close an indoor expansion valve and a gas relay shutoff valve on the basis of information from a refrigerant leakage detector.
    Type: Application
    Filed: April 16, 2019
    Publication date: August 8, 2019
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Yuusuke NAKAGAWA, Yuusuke OKA
  • Publication number: 20190234643
    Abstract: An air conditioner, in which a liquid-pressure adjustment expansion valve that decompresses a refrigerant so that the refrigerant flowing through a liquid-refrigerant connection pipe is in a gas-liquid two-phase state is provided in an outdoor liquid-refrigerant pipe that connects a liquid-side end of an outdoor heat exchanger to the liquid-refrigerant connection pipe, properly transports the refrigerant in a two-phase state while suppressing an increase in a discharge temperature of a compressor. A liquid injection pipe that branches part of a refrigerant flowing through an outdoor liquid-refrigerant pipe and feeds the branched refrigerant to a compressor is connected to a portion of the outdoor liquid-refrigerant pipe on a side of an outdoor heat exchanger with respect to a liquid-pressure adjustment expansion valve.
    Type: Application
    Filed: September 26, 2017
    Publication date: August 1, 2019
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Yuusuke NAKAGAWA, Masahiro HONDA, Yuusuke OKA
  • Publication number: 20190234660
    Abstract: An air conditioning system, which is a refrigeration apparatus that performs a refrigeration cycle in a refrigerant circuit, includes an outdoor heat exchanger, an indoor heat exchanger, a first control valve, a second control valve, a third control valve, and a pressure adjusting portion. The first control valve and the second control valve, which block flow of refrigerant when fully closed, are disposed in a gas-side refrigerant flow path. The gas-side refrigerant flow path is disposed between the outdoor heat exchanger and the indoor heat exchanger. The third control valve, which blocks flow of refrigerant when fully closed, is disposed in a liquid-side refrigerant flow path. The liquid-side refrigerant flow path is disposed between the outdoor heat exchanger and the indoor heat exchanger. The pressure adjusting portion adjusts the pressure of refrigerant in an indoor-side refrigerant flow path.
    Type: Application
    Filed: September 29, 2017
    Publication date: August 1, 2019
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Yuusuke NAKAGAWA, Yuusuke OKA, Masahiro HONDA
  • Publication number: 20190212042
    Abstract: Noise that is generated from an indoor unit is suppressed when performing two-phase transport of refrigerant by using a liquid-pressure-adjusting expansion valve in an air conditioner including an outdoor unit, a plurality of indoor units each including an indoor heat exchanger, a relay unit that switches the plurality of indoor heat exchangers so that the indoor heat exchangers individually function as an evaporator or radiator for refrigerant, and a liquid-refrigerant connection pipe and a gas-refrigerant connection pipe that connect the outdoor unit and the indoor unit via the relay unit. The relay unit includes a relay expansion valve that further decompresses the refrigerant that has been decompressed by the liquid-pressure-adjusting expansion valve.
    Type: Application
    Filed: September 26, 2017
    Publication date: July 11, 2019
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Yuusuke NAKAGAWA, Yuusuke OKA, Masahiro HONDA
  • Patent number: 10184683
    Abstract: A multi-type air conditioning device controls an evaporation temperature and a condensing temperature, depending on required capacity of an indoor unit. The air conditioning device compares a current evaporation temperature or condensing temperature with a reference value, of an evaporation temperature or an condensing temperature, corresponding to a lower limit flow rate, of a gaseous refrigerant, required for refrigerating machine oil not to accumulate in, but to flow through, the gas branch pipes, and calculates an amount of the refrigerating machine oil accumulated in a gas branch pipe which does not satisfy the lower limit flow rate. When the calculated amount exceeds a set amount, the air conditioning device performs oil collecting operation, and controls the oil collecting operation in view of a flow rate of a gaseous refrigerant in gas branch pipes.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: January 22, 2019
    Assignee: Daikin Industries, Ltd.
    Inventors: Ryuuta Ohura, Yuusuke Oka, Junya Minami
  • Patent number: 10139144
    Abstract: A controller of an air conditioning apparatus performs a start/stop frequency-reducing rotation speed control in which the rotation speed of a compressor is controlled based on request values from indoor units requesting a decrease in air conditioning capacity, disregarding request values from indoor units requesting an increase in air conditioning capacity, when each indoor temperature at all indoor units performing air conditioning operation is within a scope of a prescribed threshold temperature range surrounding a target indoor temperature at each indoor unit performing air conditioning operation.
    Type: Grant
    Filed: December 7, 2015
    Date of Patent: November 27, 2018
    Assignee: Daikin Industries, Ltd.
    Inventors: Yoshiyuki Tsuji, Yasushi Hori, Mariko Takakura, Yuusuke Oka
  • Publication number: 20180274836
    Abstract: A controller of an air conditioning apparatus performs a start/stop frequency-reducing rotation speed control in which the rotation speed of a compressor is controlled based on request values from indoor units requesting a decrease in air conditioning capacity, disregarding request values from indoor units requesting an increase in air conditioning capacity, when each indoor temperature at all indoor units performing air conditioning operation is within a scope of a prescribed threshold temperature range surrounding a target indoor temperature at each indoor unit performing air conditioning operation.
    Type: Application
    Filed: December 7, 2015
    Publication date: September 27, 2018
    Inventors: Yoshiyuki TSUJI, Yasushi HORI, Mariko TAKAKURA, Yuusuke OKA