Patents by Inventor Eiji Kumakura

Eiji Kumakura 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: 20220003461
    Abstract: In order to increase the evaporation capacity of a use-side heat exchanger regardless of operating conditions, a suction injection pipe and a subcooling heat exchanger are provided at a main refrigerant circuit in which a main refrigerant circulates. Further, a sub-refrigerant circuit that differs from the main refrigerant circuit and in which a sub-refrigerant circulates is provided. A controller performs control for switching between a cooling action of the subcooling heat-exchanger that cools the main refrigerant that is sent to a main use-side heat exchanger by using the suction injection pipe and the subcooling heat exchanger, and a cooling action of the sub-refrigerant-circuit that cools the main refrigerant that is sent to the main use-side heat exchanger by using the sub-refrigerant circuit 80.
    Type: Application
    Filed: September 27, 2019
    Publication date: January 6, 2022
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Ikuhiro IWATA, Eiji KUMAKURA, Kazuhiro FURUSHO, Ryusuke FUJIYOSHI, Hiromune MATSUOKA
  • Publication number: 20220003470
    Abstract: Efficiency in refrigerant charging work is addressed when a refrigerant recovered from the first heat source unit is to be charged to a second heat source unit. In a refrigerant charging method in which a first heat source unit of an already installed refrigeration cycle apparatus in which a refrigeration cycle is to be performed by a refrigerant that circulates is replaced with a second heat source unit, transferring the refrigerant from the first heat source unit to the second heat source unit is included. In addition, the method includes measuring the weight of the refrigerant that is transferred from the first heat source unit to the second heat source unit.
    Type: Application
    Filed: September 20, 2019
    Publication date: January 6, 2022
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Atsushi YOSHIMI, Eiji KUMAKURA, Ikuhiro IWATA
  • Publication number: 20220003469
    Abstract: There is provided a refrigerant charging method in which a foreign material and moisture are avoided from entering a heat source unit until a refrigeration cycle apparatus is configured. The refrigerant charging method is a method of charging a refrigerant to a refrigerant circuit in which a refrigeration cycle is to be performed by a circulating refrigerant, the refrigerant circuit being configured by connecting a second heat source unit and a utilization unit to each other. The refrigerant charging method includes charging a first refrigerant to the second heat source unit before connecting the second heat source unit to the utilization unit to configure the refrigerant circuit, and connecting the second heat source unit to the utilization unit and charging a second refrigerant that differs from the first refrigerant to the refrigerant circuit to obtain the circulating refrigerant that includes the second refrigerant and the first refrigerant that is charged in the second heat source unit.
    Type: Application
    Filed: September 20, 2019
    Publication date: January 6, 2022
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Atsushi YOSHIMI, Eiji KUMAKURA, Ikuhiro IWATA, Shun OHKUBO
  • Patent number: 11209195
    Abstract: An air conditioner (1, 101) has a refrigerant circuit (10, 110) which is formed by connecting an outdoor unit (2, 102) and an indoor unit (3). The refrigerant circuit (10, 110) has a refrigerant sealed therein. The refrigerant contains a hydrofluorocarbon having a property of undergoing a disproportionation reaction. The refrigerant circuit (10, 110) includes a refrigerant shutoff mechanism (24, 41, 43, 46, 47, 48) that shuts off a flow of the refrigerant from the outdoor unit (2, 102) side to the indoor unit (3) side when the refrigerant in a portion of the refrigerant circuit (10, 110) within the outdoor unit (2, 102) meets a predetermined condition.
    Type: Grant
    Filed: March 23, 2018
    Date of Patent: December 28, 2021
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji Kumakura, Tetsuya Okamoto
  • Publication number: 20210372671
    Abstract: A refrigeration cycle device that includes a main refrigerant circuit and a sub-refrigerant circuit cools or heats a main refrigerant that flows between a main heat-source-side heat exchanger and a main usage-side heat exchanger by causing a sub-usage-side heat exchanger to function as an evaporator or a radiator of a sub-refrigerant. A first main expansion mechanism and a second main expansion mechanism that decompress the main refrigerant are provided on an upstream side and a downstream side of the sub-usage-side heat exchanger of the main refrigerant circuit.
    Type: Application
    Filed: September 30, 2019
    Publication date: December 2, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Ikuhiro IWATA, Eiji KUMAKURA, Kazuhiro FURUSHO, Ryusuke FUJIYOSHI, Hiromune MATSUOKA
  • Publication number: 20210356177
    Abstract: At a refrigeration cycle device, an injection pipe and an economizer heat exchanger are provided at a main refrigerant circuit. In addition, the refrigeration cycle device includes a sub-refrigerant circuit having a sub-usage-side heat exchanger. At the refrigeration cycle device, the sub-usage-side heat exchanger functions as an evaporator of a sub-refrigerant and cools a main refrigerant that has been cooled at the economizer heat exchanger, or functions as a radiator of the sub-refrigerant and heats the main refrigerant that has been cooled at the economizer heat exchanger.
    Type: Application
    Filed: September 30, 2019
    Publication date: November 18, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Ikuhiro IWATA, Kazuhiro FURUSHO, Ryusuke FUJIYOSHI, Hiromune MATSUOKA
  • Publication number: 20210348816
    Abstract: Efficiency in refrigerant charging work is addressed when a recovered refrigerant recovered from a first heat source unit is to be charged to a second heat source unit. A refrigerant charging method is a charging method used when a first heat source unit of an already installed refrigeration cycle apparatus in which a refrigeration cycle is to be performed by a refrigerant that circulates is to be replaced with a second heat source unit. The refrigerant charging method includes recovering a first refrigerant from an already installed refrigeration cycle apparatus and obtaining a recovered refrigerant and charging the recovered refrigerant and charging a second refrigerant whose composition differs from the composition of the recovered refrigerant to the refrigeration cycle apparatus after renewal that includes the second heat source unit.
    Type: Application
    Filed: September 20, 2019
    Publication date: November 11, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Atsushi YOSHIMI, Eiji KUMAKURA, Ikuhiro IWATA, Shun OHKUBO
  • Publication number: 20210348815
    Abstract: A refrigeration cycle apparatus is caused to be in a normally operable state in accordance with the mixture ratio of difluoromethane occupying a refrigerant charged in the refrigeration cycle apparatus. A refrigeration cycle apparatus includes a refrigerant circuit including a compressor and performs a refrigeration cycle by circulating a refrigerant in the refrigerant circuit with the compressor. A heat-source-side controller judges the mixture ratio of difluoromethane occupying the refrigerant charged in the refrigerant circuit. The heat-source-side controller further performs control relating to the refrigeration cycle on the basis of the mixture ratio of difluoromethane judged by the judgement unit.
    Type: Application
    Filed: September 20, 2019
    Publication date: November 11, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro YAMADA, Atsushi YOSHIMI, Eiji KUMAKURA, Ikuhiro IWATA
  • Patent number: 11143446
    Abstract: As a refrigerant, a refrigerant containing a fluorocarbon having a property of causing a disproportionation reaction is used. A refrigeration apparatus includes: a refrigerant temperature detector configured to detect a discharged refrigerant temperature which is a temperature of the refrigerant that is being discharged from the compression mechanism or immediately after the discharge; and a controller configured to control the discharged refrigerant temperature detected by the refrigerant temperature detector such that the discharged refrigerant temperature is equal to or lower than a predetermined temperature Ts.
    Type: Grant
    Filed: July 29, 2019
    Date of Patent: October 12, 2021
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji Kumakura, Kazuhiro Furusho
  • Publication number: 20210309902
    Abstract: No studies have been made regarding what kinds of refrigerants should be used in a refrigeration cycle device for a vehicle. An air conditioner (1) for a vehicle includes a refrigerant circuit (10) and a refrigerant that is sealed in the refrigerant circuit (10). The refrigerant circuit (10) includes a compressor (80), a first heat exchanger (85), which serves as a heat dissipater in a dehumidifying heating mode, an outside-air heat exchanger (82), a cooling control valve (87), and a second heat exchanger (86), which serves as an evaporator in the dehumidifying heating mode. The refrigerant is a refrigerant having a low GWP.
    Type: Application
    Filed: July 16, 2019
    Publication date: October 7, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Kazuhiro FURUSHO, Masaru TANAKA, Shun OHKUBO, Mitsushi ITANO, Yuuki YOTSUMOTO, Akihito MIZUNO, Tomoyuki GOTOU, Yasufu YAMADA, Tatsumi TSUCHIYA, Kenji GOBOU, Hitomi KUROKI, Daisuke KARUBE, Tatsuya TAKAKUWA, Tetsushi TSUDA
  • Patent number: 11112154
    Abstract: A control unit (19) that controls the operation of a refrigerant circuit (10) executes pump down operation in which a non-azeotropic refrigerant mixture is collected into a portion of the refrigerant circuit (10) within an outdoor unit (2), executes compositional ratio determination in which the compositional ratio of the non-azeotropic refrigerant mixture is determined based on the pressure and temperature of the non-azeotropic refrigerant mixture collected into the outdoor unit (2) by the pump down operation, and generates an alert when the compositional ratio of the non-azeotropic refrigerant mixture determined by the compositional ratio determination is outside an acceptable proportion range of a hydrofluorocarbon having the property of undergoing a disproportionation reaction.
    Type: Grant
    Filed: March 23, 2018
    Date of Patent: September 7, 2021
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji Kumakura, Ikuhiro Iwata, Tetsuya Okamoto
  • Publication number: 20210215398
    Abstract: Even if, in decompressing a refrigerant by an expansion mechanism, the temperature of the refrigerant cannot be sufficiently reduced, in order to increase the evaporation capacity of a use-side heat exchanger, a main expansion mechanism including an expansion element of a rotary or scroll type that causes power to be produced by decompressing a main refrigerant is provided at a main refrigerant circuit in which the main refrigerant circulates. Further, a sub-refrigerant circuit that differs from the main refrigerant circuit and in which a sub-refrigerant circulates is provided. A sub-use-side heat exchanger that is provided at the sub-refrigerant circuit and that functions as an evaporator of the sub-refrigerant is caused to function as a heat exchanger that cools the main refrigerant that flows between the main expansion mechanism and a main use-side heat exchanger.
    Type: Application
    Filed: March 31, 2021
    Publication date: July 15, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Ikuhiro IWATA, Eiji KUMAKURA, Kazuhiro FURUSHO, Ryusuke FUJIYOSHI, Hiromune MATSUOKA
  • Publication number: 20210164703
    Abstract: An air-conditioning unit that is able to suppress ignition at an electric heater even when leakage of refrigerant occurs while a low-GWP refrigerant is used is provided. In an outdoor unit (20) including a casing (60), a compressor (21) provided inside the casing (60) and configured to compress refrigerant containing 1,2-difluoroethylene, and a drain pan heater (54) provided inside the casing (60), an electric power consumption of the drain pan heater (54) is lower than or equal to 300 W.
    Type: Application
    Filed: December 10, 2018
    Publication date: June 3, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Takuro YAMADA, Atsushi YOSHIMI, Ikuhiro IWATA, Mitsushi ITANO, Daisuke KARUBE, Yuuki YOTSUMOTO, Kazuhiro TAKAHASHI, Yuzo KOMATSU, Shun OHKUBO, Tatsuya TAKAKUWA
  • Publication number: 20210163804
    Abstract: A refrigeration cycle apparatus (10) includes a refrigerant circuit (11) including a compressor (12), a heat source-side heat exchanger (13), an expansion mechanism (14), and a usage-side heat exchanger (15). In the refrigerant circuit (11), a refrigerant containing at least 1,2-difluoroethylene (HFO-1132 (E)) is sealed. At least during a predetermined operation, in at least one of the heat source-side heat exchanger (13) and the usage-side heat exchanger (15), a flow of the refrigerant and a flow of a heating medium that exchanges heating with the refrigerant are counter flows.
    Type: Application
    Filed: December 17, 2018
    Publication date: June 3, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Takuro YAMADA, Atsushi YOSHIMI, Ikuhiro IWATA, Mitsushi ITANO, Daisuke KARUBE, Yuuki YOTSUMOTO, Kazuhiro TAKAHASHI, Tatsuya TAKAKUWA, Yuzo KOMATSU, Shun OHKUBO
  • Publication number: 20210148611
    Abstract: An air conditioner (1, 101) has a refrigerant circuit (10, 110) which is formed by connecting an outdoor unit (2, 102) and an indoor unit (3). The refrigerant circuit (10, 110) has a refrigerant sealed therein. The refrigerant contains a hydrofluorocarbon having a property of undergoing a disproportionation reaction. The refrigerant circuit (10, 110) includes a refrigerant shutoff mechanism (24, 41, 43, 46, 47, 48) that shuts off a flow of the refrigerant from the outdoor unit (2, 102) side to the indoor unit (3) side when the refrigerant in a portion of the refrigerant circuit (10, 110) within the outdoor unit (2, 102) meets a predetermined condition.
    Type: Application
    Filed: March 23, 2018
    Publication date: May 20, 2021
    Inventors: Eiji KUMAKURA, Tetsuya OKAMOTO
  • Publication number: 20210095897
    Abstract: A heat source unit and a refrigeration cycle apparatus that are able to reduce damage to a connection pipe when a refrigerant containing at least 1,2-difluoroethylene is used are provided. An outdoor unit (20) that is connected via a liquid-side connection pipe (6) and a gas-side connection pipe (5) to an indoor unit (30) including an indoor heat exchanger (31) and that is a component of an air conditioner (1) includes a compressor (21) and an outdoor heat exchanger (23). A refrigerant containing at least 1,2-difluoroethylene is used as a refrigerant. A design pressure of the outdoor unit (20) is lower than 1.5 times a design pressure of each of the liquid-side connection pipe (6) and the gas-side connection pipe (5).
    Type: Application
    Filed: December 17, 2018
    Publication date: April 1, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Takuro YAMADA, Atsushi YOSHIMI, Ikuhiro IWATA, Mitsushi ITANO, Daisuke KARUBE, Yuuki YOTSUMOTO, Kazuhiro TAKAHASHI, Tatsuya TAKAKUWA, Yuzo KOMATSU, Shun OHKUBO
  • Publication number: 20210003323
    Abstract: An air conditioning unit capable of performing a refrigeration cycle using a small-GWP refrigerant is provided. A refrigeration cycle apparatus (1, 1a to 1m) includes a refrigerant circuit (10) including a compressor (21), a condenser (23, 31, 36), a decompressing section (24, 44, 45, 33, 38), and an evaporator (31, 36, 23), and a refrigerant containing at least 1,2-difluoroethylene enclosed in the refrigerant circuit (10).
    Type: Application
    Filed: December 10, 2018
    Publication date: January 7, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Takuro YAMADA, Atsushi YOSHIMI, Ikuhiro IWATA, Mitsushi ITANO, Daisuke KARUBE, Yuuki YOTSUMOTO, Kazuhiro TAKAHASHI, Tatsuya TAKAKUWA, Yuzo KOMATSU, Shun OHKUBO
  • Publication number: 20200393178
    Abstract: A refrigeration cycle apparatus that is able to suppress a decrease in capacity when a refrigerant that contains at least 1,2-difluoroethylene is used is provided. In an air conditioner (1) including a refrigerant circuit (10) in which a compressor (21), an outdoor heat exchanger (23), an outdoor expansion valve (24), a liquid-side connection pipe (6), an indoor heat exchanger (31), and a gas-side connection pipe (5) are connected, a refrigerant containing at least 1,2-difluoroethylene is used, a pipe outer diameter of the liquid-side connection pipe (6) and a pipe outer diameter of the gas-side connection pipe (5) each are D0/8 inches (where, “D0-? inches” is a pipe outer diameter of a connection pipe when refrigerant R32 is used), a range of the D0 of the liquid-side connection pipe (6) is “2?D0?4”, and a range of the D0 of the gas-side connection pipe (5) is “3?D0?8”.
    Type: Application
    Filed: June 25, 2020
    Publication date: December 17, 2020
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Takuro YAMADA, Atsushi YOSHIMI, Ikuhiro IWATA, Mitsushi ITANO, Daisuke KARUBE, Yuuki YOTSUMOTO, Kazuhiro TAKAHASHI, Tatsuya TAKAKUWA, Yuzo KOMATSU, Shun OHKUBO
  • Publication number: 20200362215
    Abstract: A refrigeration cycle apparatus that is able to suppress a decrease in capacity when a refrigerant that contains at least 1,2-difluoroethylene is used is provided. In an air conditioner (1) including a refrigerant circuit (10) in which a compressor (21), an outdoor heat exchanger (23), an outdoor expansion valve (24), a liquid-side connection pipe (6), an indoor heat exchanger (31), and a gas-side connection pipe (5) are connected, a refrigerant containing at least 1,2-difluoroethylene is used, a pipe outer diameter of the liquid-side connection pipe (6) and a pipe outer diameter of the gas-side connection pipe (5) each are D0/8 inches (where, “D0-? inches” is a pipe outer diameter of a connection pipe when refrigerant R32 is used), a range of the D0 of the liquid-side connection pipe (6) is “2?D0?4”, and a range of the D0 of the gas-side connection pipe (5) is “3?D0?8”.
    Type: Application
    Filed: December 18, 2018
    Publication date: November 19, 2020
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Takuro YAMADA, Atsushi YOSHIMI, Ikuhiro IWATA, Mitsushi ITANO, Daisuke KARUBE, Yuuki YOTSUMOTO, Kazuhiro TAKAHASHI, Tatsuya TAKAKUWA, Yuzo KOMATSU, Shun OHKUBO
  • Publication number: 20200363105
    Abstract: An air-conditioning unit that is able to suppress ignition at an electric heater even when leakage of refrigerant occurs while a low-GWP refrigerant is used is provided. In an outdoor unit (20) including a casing (60), a compressor (21) provided inside the casing (60) and configured to compress refrigerant containing 1,2-difluoroethylene, and a drain pan heater (54) provided inside the casing (60), an electric power consumption of the drain pan heater (54) is lower than or equal to 300 W.
    Type: Application
    Filed: June 25, 2020
    Publication date: November 19, 2020
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Takuro YAMADA, Atsushi YOSHIMI, Ikuhiro IWATA, Mitsushi ITANO, Daisuke KARUBE, Yuuki YOTSUMOTO, Kazuhiro TAKAHASHI, Yuzo KOMATSU, Shun OHKUBO, Tatsuya TAKAKUWA