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: 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
  • Publication number: 20200332166
    Abstract: A refrigeration cycle apparatus (1) is capable of performing a refrigeration cycle using a small-GWP refrigerant. The refrigeration cycle apparatus (1) includes a refrigerant circuit (10) and a refrigerant enclosed in the refrigerant circuit (10). The refrigerant circuit includes a compressor (21), a condenser (23), a decompressing section (24), and an evaporator (31). The refrigerant contains at least 1,2-difluoroethylene.
    Type: Application
    Filed: December 18, 2018
    Publication date: October 22, 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, Keisuke OHTSUKA, Yoshinari ASANO, Keiji AOTA, Yuuichi YANAGI, Yoshikazu NAKAO, Takeo ABE, Yumi TODA, Tetsushi TSUDA
  • Publication number: 20200333051
    Abstract: A refrigeration cycle is a refrigeration cycle using a mixed refrigerant which is a flammable refrigerant and which contains at least 1,2-difluoroethylene (HFO-1132(E)), and includes a compressor (1), a heat-source-side heat exchanger (3), an expansion mechanism (4), a use-side heat exchanger (2), and a decompression mechanism (7). The decompression mechanism (7) decompresses, between an inlet and an outlet of the heat-source-side heat exchanger (3), the mixed refrigerant flowing through the heat-source-side heat exchanger (3) that functions as an evaporator.
    Type: Application
    Filed: December 10, 2018
    Publication date: October 22, 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: 20200333049
    Abstract: A two-stage refrigeration apparatus (500) includes a first cycle (510) and a second cycle (520). The first cycle (510) includes a first compressor (511), a first condenser (512), a first expansion mechanism (513), and a first evaporator (514) that are arranged in such a manner as to be connected to the first cycle. A first refrigerant circulates through the first cycle. The second cycle (520) includes a second downstream-side condenser (523) and a second evaporator (527) that are arranged in such a manner as to be connected to the second cycle. A second refrigerant circulates through the second cycle. The first evaporator (514) and the second downstream-side condenser (523) constitute a cascade condenser (531). In the cascade condenser (531), heat is exchanged between the first refrigerant and the second refrigerant. At least one of the first refrigerant and the second refrigerant is a refrigerant mixture containing at least 1,2-difluoroethylene (HFO-1132(E)).
    Type: Application
    Filed: December 13, 2018
    Publication date: October 22, 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: 20200326102
    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: June 25, 2020
    Publication date: October 15, 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: 20200325377
    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: June 26, 2020
    Publication date: October 15, 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: 20200326109
    Abstract: A two-stage refrigeration apparatus (500) includes a first cycle (510) and a second cycle (520). The first cycle (510) includes a first compressor (511), a first condenser (512), a first expansion mechanism (513), and a first evaporator (514) that are arranged in such a manner as to be connected to the first cycle. A first refrigerant circulates through the first cycle. The second cycle (520) includes a second downstream-side condenser (523) and a second evaporator (527) that are arranged in such a manner as to be connected to the second cycle. A second refrigerant circulates through the second cycle. The first evaporator (514) and the second downstream-side condenser (523) constitute a cascade condenser (531). In the cascade condenser (531), heat is exchanged between the first refrigerant and the second refrigerant. At least one of the first refrigerant and the second refrigerant is a refrigerant mixture containing at least 1,2-difluoroethylene (FO-1132(E)).
    Type: Application
    Filed: June 26, 2020
    Publication date: October 15, 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: 20200325376
    Abstract: A refrigeration cycle apparatus that is able to reduce the amount of refrigerant used while reducing a pressure loss in the case where a refrigerant containing at least 1,2-difluoroethylene is used is provided. In an air conditioner (1) including a refrigerant circuit (10), including a compressor (21), an outdoor heat exchanger (23), an outdoor expansion valve (24), and an indoor heat exchanger (31), and a refrigerant containing at least 1,2-difluoroethylene and sealed in the refrigerant circuit (10), the outdoor heat exchanger (23) has a heat transfer tube (23b) of which a pipe diameter is greater than or equal to 6.35 mm and less than 10.0 mm.
    Type: Application
    Filed: June 25, 2020
    Publication date: October 15, 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: 20200326105
    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: June 25, 2020
    Publication date: October 15, 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: 20200325375
    Abstract: A refrigeration cycle apparatus capable of keeping a LCCP low when a heat cycle is performed using a sufficiently small-GWP refrigerant, and a method of determining a refrigerant enclosure amount in the refrigeration cycle apparatus are provided. An outdoor unit (20) including a compressor (21) and an outdoor heat exchanger (23), an indoor unit (30) including an indoor heat exchanger (31), and a refrigerant pipe (5, 6) that connects the outdoor unit (20) and the indoor unit (30) to each other are provided. A refrigerant containing at least 1,2-difluoroethylene is enclosed in a refrigerant circuit (10) that is constituted by connecting the compressor (21), the outdoor heat exchanger (23), and the indoor heat exchanger (31) to one another. An enclosure amount of the refrigerant in the refrigerant circuit (10) per 1 kW of refrigeration capacity satisfies a condition of 160 g or more and 560 g or less.
    Type: Application
    Filed: June 25, 2020
    Publication date: October 15, 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
  • Publication number: 20200326103
    Abstract: A refrigeration cycle is a refrigeration cycle using a mixed refrigerant which is a flammable refrigerant and which contains at least 1,2-difluoroethylene (HFO-1132(E)), and includes a compressor (1), a heat-source-side heat exchanger (3), an expansion mechanism (4), a use-side heat exchanger (2), and a decompression mechanism (7). The decompression mechanism (7) decompresses, between an inlet and an outlet of the heat-source-side heat exchanger (3), the mixed refrigerant flowing through the heat-source-side heat exchanger (3) that functions as an evaporator.
    Type: Application
    Filed: June 26, 2020
    Publication date: October 15, 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: 20200309437
    Abstract: A refrigeration cycle apparatus capable of keeping a LCCP low when a heat cycle is performed using a sufficiently small-GWP refrigerant, and a method of determining a refrigerant enclosure amount in the refrigeration cycle apparatus are provided. An outdoor unit (20) including a compressor (21) and an outdoor heat exchanger (23), an indoor unit (30) including an indoor heat exchanger (31), and a refrigerant pipe (5, 6) that connects the outdoor unit (20) and the indoor unit (30) to each other are provided. A refrigerant containing at least 1,2-difluoroethylene is enclosed in a refrigerant circuit (10) that is constituted by connecting the compressor (21), the outdoor heat exchanger (23), and the indoor heat exchanger (31) to one another. An enclosure amount of the refrigerant in the refrigerant circuit (10) per 1 kW of refrigeration capacity satisfies a condition of 160 g or more and 560 g or less.
    Type: Application
    Filed: December 10, 2018
    Publication date: October 1, 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
  • Publication number: 20200309419
    Abstract: A refrigeration cycle apparatus that is able to reduce the amount of refrigerant used while reducing a pressure loss in the case where a refrigerant containing at least 1,2-difluoroethylene is used is provided. In an air conditioner (1) including a refrigerant circuit (10), including a compressor (21), an outdoor heat exchanger (23), an outdoor expansion valve (24), and an indoor heat exchanger (31), and a refrigerant containing at least 1,2-difluoroethylene and sealed in the refrigerant circuit (10), the outdoor heat exchanger (23) has a heat transfer tube (23b) of which a pipe diameter is greater than or equal to 6.35 mm and less than 10.0 mm.
    Type: Application
    Filed: December 18, 2018
    Publication date: October 1, 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
  • Patent number: 10724525
    Abstract: A compressor includes a compression mechanism having a ring-shaped first cylinder, a first piston eccentrically rotatable in an interior of the first cylinder, a first cylinder head member disposed adjacent to one axial end of the first cylinder, a second cylinder head member disposed adjacent to an other axial end of the first cylinder, and a fastening bolt. The fastening bolt fastens the first cylinder head member, the first cylinder, and the second cylinder head member together. An end face of the first cylinder head member contacts the first cylinder, and the end face is provided with a protecting groove. The protecting groove is formed closer to a center of the first cylinder than the fastening bolt, and has a groove width smaller than a groove depth of the protecting groove.
    Type: Grant
    Filed: July 12, 2016
    Date of Patent: July 28, 2020
    Assignee: Daikin Industries, Ltd.
    Inventors: Yukihiro Inada, Kazuhiro Furusho, Eiji Kumakura
  • Publication number: 20200124326
    Abstract: The refrigerant device includes a refrigerant circuit performing a refrigeration cycle in which one of the heat-source-side heat exchanger and the utilization-side heat exchanger serves as a radiator, while the other serves as an evaporator. The refrigerant circuit is filled with a refrigerant including hydrocarbon fluoride having the property of causing disproportional reaction. The refrigerant circuit includes an ejector provided with a depressurization channel, a suction channel and an ejection channel, a gas-liquid separator into which a refrigerant ejected from the ejection channel flows, an expansion mechanism depressurizing a liquid refrigerant flowing from the gas-liquid separator into the evaporator, and a suction pipe guiding a gas refrigerant of the gas-liquid separator into the compressor. As a result, it is possible to reduce the risk of disproportional reaction of the refrigerant.
    Type: Application
    Filed: January 17, 2018
    Publication date: April 23, 2020
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji Kumakura, Kazuhiro Furusho
  • Publication number: 20200072518
    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: Application
    Filed: March 23, 2018
    Publication date: March 5, 2020
    Inventors: Eiji KUMAKURA, Ikuhiro IWATA, Tetsuya OKAMOTO
  • Publication number: 20190368493
    Abstract: In a compressor compressing a refrigerant including hydrocarbon fluoride prone to disproportionate, provided, on a contact portion of the drive shaft and the bearing portion, is an elastic bearing portion as a heat generation suppression portion suppressing excessive heat generation due to line contact of an end edge portion of the bearing portion with the drive shaft during rotation of the drive shaft.
    Type: Application
    Filed: January 19, 2018
    Publication date: December 5, 2019
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Kazuhiro FURUSHO
  • Publication number: 20190346192
    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: Application
    Filed: July 29, 2019
    Publication date: November 14, 2019
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Kazuhiro FURUSHO