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).

  • Patent number: 11988426
    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: Grant
    Filed: September 20, 2019
    Date of Patent: May 21, 2024
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuro Yamada, Atsushi Yoshimi, Eiji Kumakura, Ikuhiro Iwata, Shun Ohkubo
  • Patent number: 11976859
    Abstract: A refrigeration cycle apparatus includes a refrigeration cycle, an adsorption section, and a first bypass flow path. The refrigeration cycle includes a compressor, a radiator, an expansion mechanism, and an evaporator, and uses a non-azeotropic refrigerant mixture including a first refrigerant and a second refrigerant. The adsorption section includes an adsorbent and stores the first refrigerant adsorbed by the adsorbent. The adsorbent adsorbs the first refrigerant, and does not adsorb the second refrigerant or the adsorption performance thereof for the second refrigerant is lower than the adsorption performance thereof for the first refrigerant. The first bypass flow path connects a first end which is a high-pressure part of the refrigeration cycle and a second end which is a low-pressure part of the refrigeration cycle. The adsorption section and a valve are disposed in the first bypass flow path.
    Type: Grant
    Filed: September 29, 2023
    Date of Patent: May 7, 2024
    Assignee: Daikin Industries, Ltd.
    Inventors: Hiroki Ueda, Atsushi Yoshimi, Eiji Kumakura, Masaki Tanaka, Masaki Nakayama, Ryuhei Kaji
  • Patent number: 11976851
    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: Grant
    Filed: September 30, 2019
    Date of Patent: May 7, 2024
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Ikuhiro Iwata, Eiji Kumakura, Kazuhiro Furusho, Ryusuke Fujiyoshi, Hiromune Matsuoka
  • Patent number: 11971037
    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: Grant
    Filed: August 9, 2022
    Date of Patent: April 30, 2024
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji Kumakura, Kazuhiro Furusho
  • Patent number: 11959667
    Abstract: 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.
    Type: Grant
    Filed: September 27, 2019
    Date of Patent: April 16, 2024
    Assignee: Daikin Industries, Ltd.
    Inventors: Ikuhiro Iwata, Eiji Kumakura, Kazuhiro Furusho, Ryusuke Fujiyoshi, Hiromune Matsuoka
  • Patent number: 11920077
    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: Grant
    Filed: July 16, 2019
    Date of Patent: March 5, 2024
    Assignee: 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: 11906207
    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: Grant
    Filed: June 26, 2020
    Date of Patent: February 20, 2024
    Assignee: 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: 20240027115
    Abstract: In an air conditioner, during an operation, a gas-liquid two-phase non-azeotropic mixture refrigerant enters a receiver and accumulates in the receiver in a state where a gas phase and a liquid phase are separated. For example, when the non-azeotropic mixture refrigerant includes two components, i.e., a high-boiling refrigerant and a low-boiling refrigerant, the controller may estimate the ratio (composition ratio) between the low-boiling refrigerant and the high-boiling refrigerant in each of the gas phase and the liquid phase based on the temperature and the pressure of the non-azeotropic mixture refrigerant in the receiver. Thus, the controller may estimate the composition ratio of the liquid-phase non-azeotropic mixture refrigerant flowing out of the receiver as the composition ratio of the non-azeotropic mixture refrigerant circulating in the refrigerant circuit.
    Type: Application
    Filed: September 28, 2023
    Publication date: January 25, 2024
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji KUMAKURA, Ryuhei KAJI, Atsushi YOSHIMI, Masaki TANAKA, Hiroki UEDA, Masaki NAKAYAMA
  • Publication number: 20240027104
    Abstract: A refrigeration cycle apparatus includes a first refrigerant circuit and a second refrigerant circuit so as to improve the efficiency of operations. A first refrigerant circuit using a first refrigerant having a pressure of 1.2 MPa or less at 30° C. and a second refrigerant circuit using a second refrigerant having a pressure of 1.5 MPa or more at 30° C. are provided, and a dual cycle operation in which the first refrigerant circuit and the second refrigerant circuit are simultaneously operated to exchange heat between the first refrigerant and the second refrigerant and a single cycle operation in which the first refrigerant circuit is operated without operating the second refrigerant circuit to perform a cooling operation or heating operation are enabled in a switchable manner.
    Type: Application
    Filed: September 28, 2023
    Publication date: January 25, 2024
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Hiroki IKARASHI, Atsushi YOSHIMI, Takuro YAMADA, Eiji KUMAKURA, Ikuhiro IWATA, Ryuhei KAJI, Takeru MIYAZAKI, Hiroki UEDA, Masaki TANAKA, Masaki NAKAYAMA, Hideho SAKAGUCHI, Osamu TANAKA, Hirokazu FUJINO
  • Publication number: 20240027105
    Abstract: A refrigeration cycle apparatus efficiently performs a cooling operation and a heating operation using a low-pressure refrigerant and a high-pressure refrigerant. A refrigeration cycle apparatus using a first refrigerant having 1 MPa or less at 30° C. and a second refrigerant having 1.5 MPa or more at 30° C. performs a heating operation by performing a two-stage refrigeration cycle including a use-side refrigeration cycle using the first refrigerant and a heat-source-side refrigeration cycle using the second refrigerant, and performs a cooling operation by performing a single-stage refrigeration cycle using the first refrigerant.
    Type: Application
    Filed: September 29, 2023
    Publication date: January 25, 2024
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Atsushi YOSHIMI, Takuro YAMADA, Eiji KUMAKURA, Ikuhiro IWATA, Takeru MIYAZAKI, Hiroki UEDA, Masaki TANAKA, Masaki NAKAYAMA, Osamu TANAKA, Hirokazu FUJINO, Ryuhei KAJI
  • Publication number: 20240019183
    Abstract: A refrigerant recovery system includes a cylinder, a first detection unit, and a control unit. The cylinder accommodate a refrigerant filling a refrigeration cycle apparatus. The first detection unit detects a predetermined physical quantity in order to calculate a composition of the refrigerant accommodated in the cylinder. The control unit acquires a result of detection by the first detection unit and outputs the result as a first detection result.
    Type: Application
    Filed: September 26, 2023
    Publication date: January 18, 2024
    Inventors: Ryuhei KAJI, Eiji KUMAKURA, Atsushi YOSHIMI, Masaki TANAKA, Hiroki UEDA, Masaki NAKAYAMA
  • Publication number: 20240017595
    Abstract: A refrigeration cycle device for a vehicle includes a refrigerant circuit, in which a zeotropic refrigerant mixture is circulated, including a utilization heat exchanger including a first heat exchange portion and a second heat exchange portion disposed in series with the first heat exchange portion in a direction in which the zeotropic refrigerant mixture flows in the refrigerant circuit. The first heat exchange portion is disposed on an upstream side of the second heat exchange portion in a direction in which the zeotropic refrigerant mixture flows when the utilization heat exchanger functions as an evaporator of the zeotropic refrigerant mixture.
    Type: Application
    Filed: September 28, 2023
    Publication date: January 18, 2024
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Ikuhiro Iwata, Eiji Kumakura, Tetsushi Tsuda, Shinjiro Domi
  • Publication number: 20240019181
    Abstract: A refrigeration cycle apparatus includes a refrigeration cycle, an adsorption section, and a first bypass flow path. The refrigeration cycle includes a compressor, a radiator, an expansion mechanism, and an evaporator, and uses a non-azeotropic refrigerant mixture including a first refrigerant and a second refrigerant. The adsorption section includes an adsorbent and stores the first refrigerant adsorbed by the adsorbent. The adsorbent adsorbs the first refrigerant, and does not adsorb the second refrigerant or the adsorption performance thereof for the second refrigerant is lower than the adsorption performance thereof for the first refrigerant. The first bypass flow path connects a first end which is a high-pressure part of the refrigeration cycle and a second end which is a low-pressure part of the refrigeration cycle. The adsorption section and a valve are disposed in the first bypass flow path.
    Type: Application
    Filed: September 29, 2023
    Publication date: January 18, 2024
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Hiroki UEDA, Atsushi YOSHIMI, Eiji KUMAKURA, Masaki TANAKA, Masaki NAKAYAMA, Ryuhei KAJI
  • Publication number: 20240019177
    Abstract: An air conditioner, which is a heat pump apparatus, includes a refrigerant circuit, a compressor, and a composition adjustment mechanism. The refrigerant circuit circulates a non-azeotropic mixture refrigerant including a first refrigerant and a second refrigerant having a boiling point higher than the first refrigerant. The compressor compresses the non-azeotropic mixture refrigerant. The first refrigerant is a compound represented by a molecular formula having one or more carbon-carbon unsaturated bonds. The composition adjustment mechanism is provided in the refrigerant circuit. The composition adjustment mechanism prevents an increase in the rate of the first refrigerant included in the non-azeotropic mixture refrigerant discharged from the compressor.
    Type: Application
    Filed: September 28, 2023
    Publication date: January 18, 2024
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Ikuhiro IWATA, Eiji KUMAKURA, Tetsushi TSUDA, Shinjiro DOMI, Atsushi YOSHIMI
  • Publication number: 20240019176
    Abstract: A refrigeration cycle apparatus efficiently performs a cooling operation and a heating operation using a low-pressure refrigerant and a high-pressure refrigerant. A refrigeration cycle apparatus performs a heating operation by performing a two-stage refrigeration cycle, the two-stage refrigeration cycle including a use-side refrigeration cycle using a first refrigerant having 1 MPa or less at 30° C. and a heat-source-side refrigeration cycle using a second refrigerant having 1.5 MPa or Imre at 30° C., and performs a cooling operation by performing a single-stage refrigeration cycle using the first refrigerant.
    Type: Application
    Filed: September 29, 2023
    Publication date: January 18, 2024
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Atsushi YOSHIMI, Takuro YAMADA, Eiji KUMAKURA, Ikuhiro IWATA, Ryuhei KAJI, Takeru MIYAZAKI, Hiroki UEDA, Masaki TANAKA, Masaki NAKAYAMA
  • Publication number: 20240019184
    Abstract: A refrigerant recovery system performs separation of a first refrigerant from a refrigerant including the first refrigerant, and recovery of the refrigerant. The refrigerant recovery system includes a separation unit that perform the separation of the first refrigerant, and a storage unit that stores the refrigerant before the first refrigerant is separated or after the first refrigerant is separated.
    Type: Application
    Filed: September 27, 2023
    Publication date: January 18, 2024
    Inventors: Hiroki UEDA, Atsushi YOSHIMI, Eiji KUMAKURA, Masaki TANAKA, Masaki NAKAYAMA, Ryuhei KAJI
  • Publication number: 20240019178
    Abstract: A refrigeration cycle apparatus includes a main refrigerant circuit, a changer, and a controller. The main refrigerant circuit uses a non-azeotropic refrigerant mixture containing a first refrigerant and a second refrigerant. The changer changes a composition ratio between the first refrigerant and the second refrigerant in a refrigerant flowing through the main refrigerant circuit. The controller controls an operation of the changer. The controller executes a first mode and a second mode. The first mode is a mode in which the operation of the changing unit is controlled to cause substantially the second refrigerant alone to flow through the main refrigerant circuit. The second mode is a mode in which the operation of the changing unit is controlled to cause a refrigerant mixture of the first refrigerant and the second refrigerant to flow through the main refrigerant circuit.
    Type: Application
    Filed: September 28, 2023
    Publication date: January 18, 2024
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Masaki TANAKA, Eiji KUMAKURA, Ikuhiro IWATA, Ryuhei KAJI, Atsushi YOSHIMI, Hiroki UEDA, Takuro YAMADA, Masaki NAKAYAMA
  • Publication number: 20230417459
    Abstract: A refrigeration cycle apparatus includes a refrigerant circuit and an adsorbent. The refrigerant circuit includes a compressor that compresses a refrigerant. The refrigerant circuit configures a vapor compression refrigeration cycle in which the refrigerant circulates. The adsorbent adsorbs and desorbs the refrigerant circulating in the refrigerant circuit. The adsorbent adsorbs and desorbs the refrigerant in accordance with a change in a pressure of the refrigerant circulating in the refrigerant circuit.
    Type: Application
    Filed: June 27, 2023
    Publication date: December 28, 2023
    Applicants: DAIKIN INDUSTRIES, LTD., The University of Tokyo
    Inventors: Eiji KUMAKURA, Ryuhei KAJI, Hiroki UEDA, Masaki TANAKA, Kosuke NISHIMURA, Kazuhiro FURUSHO, Yoshimasa KIKUCHI, Hirofumi DAIGUJI, Arun MAJUMDAR, Wei-Lun HSU, Jubair Ahmed SHAMIM
  • Publication number: 20230417460
    Abstract: A refrigerant circuit includes a compressor that compresses refrigerant and an expansion mechanism that decompresses refrigerant. The refrigerant circuit configures a vapor compression refrigeration cycle in which the refrigerant circulates. The adsorbent adsorbs and desorbs the refrigerant circulating in a first unit. The refrigerant circuit includes a high-pressure region and a low-pressure region. The refrigeration cycle apparatus is operated under at least one of a first condition and a second condition. In the first condition, the refrigerant in the high-pressure region has a pressure lower than or equal to a critical pressure of the refrigerant, and the refrigerant in the high-pressure region has a temperature exceeding a critical temperature of the refrigerant.
    Type: Application
    Filed: June 27, 2023
    Publication date: December 28, 2023
    Applicants: DAIKIN INDUSTRIES, LTD., The University of Tokyo
    Inventors: Eiji KUMAKURA, Hirofumi DAIGUJI, Arun MAJUMDAR, Wei-Lun HSU, Jubair Ahmed SHAMIM
  • Patent number: 11820933
    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: Grant
    Filed: June 26, 2020
    Date of Patent: November 21, 2023
    Assignee: 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