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: 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
  • Patent number: 10465684
    Abstract: A rotary compressor includes a cylinder having a cylinder chamber and bush groove, a piston housed in the cylinder chamber, a blade formed with the piston to separate the cylinder chamber into low and high pressure chambers, and a pair of bushes. The bushes are fitted in the bush groove with flat surfaces facing each other to hold the blade. The flat surface of at least the bush on the low-pressure side has a crowned portion starting from a position closer to the back pressure space than a swing center position, and extending toward an edge of the bush closer to the cylinder chamber. The swing center position is where a gap between the blade and the bush is constant while the piston rotates eccentrically.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: November 5, 2019
    Assignee: Daikin Industries, Ltd.
    Inventors: Kousuke Nishimura, Takeyoshi Ohkawa, Eiji Kumakura
  • Publication number: 20180202446
    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: Application
    Filed: July 12, 2016
    Publication date: July 19, 2018
    Inventors: Yukihiro INADA, Kazuhiro FURUSHO, Eiji KUMAKURA
  • Publication number: 20170218955
    Abstract: A rotary compressor includes a cylinder having a cylinder chamber and bush groove, a piston housed in the cylinder chamber, a blade formed with the piston to separate the cylinder chamber into low and high pressure chambers, and a pair of bushes. The bushes are fitted in the bush groove with flat surfaces facing each other to hold the blade. The flat surface of at least the bush on the low-pressure side has a crowned portion starting from a position closer to the back pressure space than a swing center position, and extending toward an edge of the bush closer to the cylinder chamber. The swing center position is where a gap between the blade and the bush is constant while the piston rotates eccentrically.
    Type: Application
    Filed: July 29, 2015
    Publication date: August 3, 2017
    Inventors: Kousuke NISHIMURA, Takeyoshi OHKAWA, Eiji KUMAKURA
  • Publication number: 20150107218
    Abstract: A combined cycle plant including a gas turbine, a heat recovery boiler for generating steam using exhaust heat of the gas turbine, and a steam turbine for feeding the steam generated by the heat recovery boiler from the heat recovery boiler through a steam system, characterized in that, the steam system is disposed so as to branch to a first steam system for introducing the steam to a first stage entrance of the steam turbine and a second steam system for introducing the steam to a stage entrance on a downstream side of the first stage of the steam turbine, and a flow rate of the steam fed to the steam turbine via the first steam system and the second steam system is adjusted on the basis of a steam flow rate generated by the heat recovery boiler.
    Type: Application
    Filed: October 22, 2014
    Publication date: April 23, 2015
    Inventors: Tateki NAKAMURA, Koji OGATA, Eiji KUMAKURA, Takeshi KUDO
  • Patent number: 8966920
    Abstract: A refrigeration system includes a refrigerant circuit including a compressor and an expander which expands a refrigerant and generates power, for performing a refrigeration cycle. The refrigeration system includes a compressor control section and an expander control section which, when an operation stop signal is output during operation, reduces a rotational speed of the compressor and increases a rotational speed of the expander to increase the ratio of the rotational speed of the expander to the rotational speed of the compressor.
    Type: Grant
    Filed: March 25, 2011
    Date of Patent: March 3, 2015
    Assignee: Daikin Industries, Ltd.
    Inventors: Masakazu Okamoto, Eiji Kumakura, Masanori Ukibune
  • Publication number: 20130025307
    Abstract: A refrigeration system includes a refrigerant circuit including a compressor and an expander which expands a refrigerant and generates power, for performing a refrigeration cycle. The refrigeration system includes a compressor control section and an expander control section which, when an operation stop signal is output during operation, reduces a rotational speed of the compressor and increases a rotational speed of the expander to increase the ratio of the rotational speed of the expander to the rotational speed of the compressor.
    Type: Application
    Filed: March 25, 2011
    Publication date: January 31, 2013
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Masakazu Okamoto, Eiji Kumakura, Masanori Ukibune
  • Patent number: 8312732
    Abstract: A compressor and an expander are provided in a refrigerant circuit of an air conditioner. In the compressor, refrigerator oil is supplied from an oil reservoir to a compression mechanism. In the expander, the refrigerator oil is supplied from an oil reservoir to an expansion mechanism. Internal spaces of a compressor casing and an expander casing communicate with each other through an equalizing pipe. An oil pipe connecting the compressor casing and the expander casing is provided with an oil amount adjusting valve operated on the basis of an output signal of an oil level sensor. When the oil amount adjusting valve is opened, the oil reservoir in the compressor casing and the oil reservoir in the expander casing communicate with each other to allow the refrigerator oil to flow through the oil pipe.
    Type: Grant
    Filed: April 16, 2007
    Date of Patent: November 20, 2012
    Assignee: Daikin Industries, Ltd.
    Inventors: Katsumi Sakitani, Masakazu Okamoto, Eiji Kumakura, Tetsuya Okamoto
  • Patent number: 8245528
    Abstract: In a compression/expansion unit (30) serving as a fluid machine, both of a compression mechanism (50) and an expansion mechanism (60) are contained in a single casing (31). A shaft (40) coupling the compression mechanism (50) to the expansion mechanism (60) has an oil feeding channel (90) formed therein. Refrigerating machine oil accumulated at the bottom of the casing (31) is sucked up into the oil feeding channel (90) and fed to the compression mechanism (50) and the expansion mechanism (60). The refrigerating machine oil fed to the expansion mechanism (60) is discharged from the expansion mechanism (60) together with the refrigerant after expansion, flows through the refrigerant circuit and then flows back to the compression mechanism (50) in the compression/expansion unit (30).
    Type: Grant
    Filed: March 5, 2007
    Date of Patent: August 21, 2012
    Assignee: Daikin Industries, Ltd.
    Inventors: Katsumi Sakitani, Masakazu Okamoto, Eiji Kumakura, Tetsuya Okamoto
  • Patent number: 8122735
    Abstract: A refrigerant circuit (11) of an air conditioner (10) includes a compressor (20) and an expander (30). In the compressor (20), refrigerator oil is supplied from an oil reservoir (27) to a compression mechanism (21). In the expander (30), the refrigerator oil is supplied from an oil reservoir (37) to an expansion mechanism (31). The inner pressures of the compressor casing (24) and the expander casing (34) are the high pressure and the low pressure of the refrigeration cycle, respectively. An oil adjusting valve (52) is provided in an oil pipe (42) connecting the compressor casing (24) and the expander casing (34). The oil amount adjusting valve (52) is operated on the basis of an output signal of an oil level sensor (51). When the oil amount adjusting valve (52) is opened, the refrigerator oil flows from the oil reservoir (27) in the compressor casing (24) toward the oil reservoir (37) in the expander casing (34) through the oil pipe (42).
    Type: Grant
    Filed: April 16, 2007
    Date of Patent: February 28, 2012
    Assignee: Daikin Industries, Ltd.
    Inventors: Katsumi Sakitani, Tetsuya Okamoto, Masakazu Okamoto, Eiji Kumakura
  • Patent number: 7918096
    Abstract: In a refrigerant circuit (11), a compressor (20) and an expander (30) are provided separately. An expander casing (34) is connected to a delivery pipe (26) of the compressor (20) and high pressure refrigerant passes through the inside of the expander casing (34). Therefore, the compressor casing (24) and the expander casing (34) are equalized in their internal pressure. An oil distribution pipe (41) for connection of an oil sump (27) of the compressor (20) and an oil sump (37) of the expander (30) is provided with an oil regulating valve (52). The oil regulating valve (52) is controlled in response to a signal outputted from an oil level sensor (51). When the oil regulating valve (52) is opened, the oil sump (27) within the compressor casing (24) and the oil sump (37) within the expander casing (34) fluidly communicate with each other whereby refrigeration oil travels through the oil distribution pipe (41).
    Type: Grant
    Filed: April 16, 2007
    Date of Patent: April 5, 2011
    Assignee: Daikin Industries, Ltd.
    Inventors: Katsumi Sakitani, Tetsuya Okamoto, Masakazu Okamoto, Eiji Kumakura
  • Patent number: 7896627
    Abstract: A rotary type expander is provided with two rotary mechanism parts which differ from each other in displacement volume. The outflow side of the first rotary mechanism part of small displacement volume is fluidly connected to the inflow side of the second rotary mechanism part of large displacement volume. The processes by which the volume of a first low-pressure chamber in the first rotary mechanism part decreases and the volume of a second high-pressure chamber in the second rotary mechanism part increases are respectively in sync. Refrigerant at high pressure is first introduced into a first high-pressure chamber of the first rotary mechanism part. Thereafter, this high-pressure refrigerant passes through a communicating passage and then flows by way of the first low-pressure chamber into the second high-pressure chamber while expanding. The after-expansion refrigerant flows out to an outflow port from a second low-pressure chamber of the second rotary mechanism part.
    Type: Grant
    Filed: September 3, 2004
    Date of Patent: March 1, 2011
    Assignee: Daikin Industries, Ltd.
    Inventors: Masakazu Okamoto, Michio Moriwaki, Eiji Kumakura, Tetsuya Okamoto, Katsumi Sakitani
  • Publication number: 20110002803
    Abstract: An expander includes a cylinder at which an inflow port and an outflow port are formed, a piston eccentrically disposed in the cylinder relative to a rotational shaft to form a fluid chamber between the piston and the cylinder, and a blade dividing the fluid chamber into a high pressure side and a low pressure side. The cylinder, the piston and the blade are arranged and configured such that the expander recovers power of a fluid depressurized in the fluid chamber. The cylinder has an inner diameter Dc, the inflow port has a diameter Di, and the outflow port has a diameter Do. The relationship 0.065×Dc?Di?0.13×Dc and/or 0.065×Dc?Do?0.13×Dc is satisfied.
    Type: Application
    Filed: February 26, 2009
    Publication date: January 6, 2011
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji Kumakura, Masakazu Okamoto, Masanori Ukibune, Katsumi Sakitani
  • Patent number: 7802447
    Abstract: A casing (31) houses therein an expansion mechanism (60) and a compression mechanism (50). The expansion mechanism (60) has a rear head (62) in which a pressure snubbing chamber (71) is provided. The pressure snubbing chamber (71) is divided by a piston (77) into an inflow/outflow chamber (72) which fluidly communicates with an inflow port (34) and a back pressure chamber (73) which fluidly communicates with the inside of the casing (31). The piston (77) is displaced in response to suction pressure variation whereby the volume of the inflow/outflow chamber (72) varies. This enables the inflow/outflow chamber (72) to directly perform supply of refrigerant to or suction of refrigerant from the inflow port (34) which is a source of pressure variation, thereby making it possible to effectively inhibit suction pressure variation.
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: September 28, 2010
    Assignee: Daikin Industries, Ltd.
    Inventors: Eiji Kumakura, Masakazu Okamoto, Tetsuya Okamoto, Katsumi Sakitani
  • Patent number: 7784303
    Abstract: A positive displacement expander includes a volume change mechanism (90) for changing the volume of a first fluid chamber (72) of an expansion mechanism (60). The expansion mechanism (60) includes a first rotary mechanism (70) and a second rotary mechanism (80) each having a cylinder (71, 81) containing a rotor (75, 85). The first fluid chamber (72) of the first rotary mechanism (70) and a second fluid chamber (82) of the second rotary mechanism (80) are in fluid communication with each other to form an actuation chamber (66). Meanwhile, the first fluid chamber (72) of the first rotary mechanism (70) is smaller than the second fluid chamber (82) of the second rotary mechanism (80). The volume change mechanism (90) includes an auxiliary chamber (93) fluidly communicating with the first fluid chamber (72) and an auxiliary piston (92) for changing the volume of the auxiliary chamber (93). The auxiliary chamber (93) is in fluid communication with the first fluid chamber (72) of the first rotary mechanism (70).
    Type: Grant
    Filed: August 5, 2005
    Date of Patent: August 31, 2010
    Assignee: Daikin Industries, Ltd.
    Inventors: Katsumi Sakitani, Michio Moriwaki, Masakazu Okamoto, Eiji Kumakura, Yume Inokuchi, Tetsuya Okamoto, Yoshinari Sasaki
  • Publication number: 20100101268
    Abstract: A refrigerant circuit (11) in an air conditioner (10) includes a compressor (20) and an expander (30). In the compressor (20), refrigerant compressed by a compression mechanism (21) is discharged into the internal space of a compressor casing (24). In the compressor (20), refrigeration oil which has accumulated in the bottom of the compressor casing (24) is supplied to the compression mechanism (21). The refrigeration oil in the bottom of the compressor casing (24) is directly introduced into an expansion mechanism (31) of the expander (30) through an oil supply pipe (41).
    Type: Application
    Filed: February 6, 2008
    Publication date: April 29, 2010
    Inventors: Katsumi Sakitani, Masakazu Okamoto, Eiji Kumakura
  • Publication number: 20100074769
    Abstract: A fluid machine includes a casing, a compression mechanism for compressing refrigerant, an expansion mechanism for expanding refrigerant, and a rotary shaft connecting the compression mechanism and the expansion mechanism The compression mechanism, the expansion mechanism and the rotary shaft are disposed in the casing. A heat insulator partitions an internal space of the casing into a first space with the expansion mechanism disposed therein and a second space with the compression mechanism disposed therein. The rotary shaft passes through the heat insulator. An elastically deformable seal element seals a clearance between an outer periphery of the heat insulator and an inner periphery of the casing.
    Type: Application
    Filed: November 21, 2007
    Publication date: March 25, 2010
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Eiji Kumakura, Katsumi Sakitani
  • Patent number: 7674097
    Abstract: Two rotary mechanism parts (70, 80) are provided in a rotary expander (60). The first rotary mechanism part (70) is smaller in displacement volume than the second rotary mechanism part (80). A first low-pressure chamber (74) of the first rotary mechanism part (70) and a second high-pressure chamber (83) of the second rotary mechanism part (80) are fluidly connected together by a communicating passageway (64), thereby forming a single expansion chamber (66). High-pressure refrigerant introduced into the first rotary mechanism part (70) expands in the expansion chamber (66). An injection passageway (37) is fluidly connected to the communicating passageway (64). When an motor-operated valve (90) is placed in the open state, high-pressure refrigerant is introduced into the expansion chamber (66) also from the injection passageway (37). This makes it possible to inhibit the drop in power recovery efficiency, even in the condition that causes the actual expansion ratio to fall below the design expansion ratio.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: March 9, 2010
    Assignee: Daikin Industries, Ltd.
    Inventors: Masakazu Okamoto, Michio Moriwaki, Eiji Kumakura, Tetsuya Okamoto, Katsumi Sakitani
  • Patent number: 7628592
    Abstract: In a compression/expansion unit (30) serving as a fluid machine, both a compression mechanism (50) and an expansion mechanism (60) are housed in a single casing (31). An oil supply passageway (90) is formed in a shaft (40) by which the compression mechanism (50) and the expansion mechanism (60) are coupled together. Refrigeration oil accumulated in the bottom of the casing (31) is drawn up into the oil supply passageway (90) and is supplied to the compression mechanism (50) and to the expansion mechanism (60). Surplus refrigeration oil, which is supplied to neither of the compression and expansion mechanisms (50) and (60), is discharged out of the terminating end of the oil supply passageway (90) which opens at the upper end of the shaft (40). Thereafter, the surplus refrigeration oil flows into an oil return pipe (102) from a lead-out hole (101) and is returned back towards a second space (39).
    Type: Grant
    Filed: March 9, 2005
    Date of Patent: December 8, 2009
    Assignee: Daikin Industries, Ltd.
    Inventors: Tetsuya Okamoto, Eiji Kumakura, Masakazu Okamoto, Michio Moriwaki, Katsumi Sakitani
  • Patent number: 7618242
    Abstract: A front head of a cylinder and a mounting plate are tightly fixed to each other. The mounting plate is welded to a casing. The mounting plate is made of steel containing 2.0% or less of carbon therein. Furthermore, a stator core of a compressor motor is welded to the casing. A hermetic sealed compressor is configured in a high-pressure domed type. A supercritical fluid is used as an operating fluid.
    Type: Grant
    Filed: February 25, 2003
    Date of Patent: November 17, 2009
    Assignee: Daikin Industries, Ltd.
    Inventors: Masahide Higuchi, Eiji Kumakura, Takashi Hirouchi