Patents by Inventor Tomotaka Ishikawa

Tomotaka Ishikawa 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: 10060661
    Abstract: An accumulator that is used in a refrigeration apparatus including a plurality of compressors and is provided for the plurality of compressors, the accumulator including an inlet pipe that penetrates a cylindrical container perpendicularly to a central axis of the cylindrical container and conveys gas-liquid mixed refrigerant into the container and a plurality of outlet pipes connected to respective suction sides of the plurality of compressors, wherein the plurality of outlet pipes each have one end located in the container and forming outlet port for conveying gas refrigerant in the container toward the plurality of compressors, and wherein the outlet port of each of the plurality of outlet pipes is concentrated in a central part of the container.
    Type: Grant
    Filed: February 28, 2014
    Date of Patent: August 28, 2018
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Abastari, Satoru Ue, Tomotaka Ishikawa, Kenichi Hata
  • Patent number: 10001310
    Abstract: A two-stage refrigeration apparatus includes a high-stage refrigeration cycle including a high-stage-side refrigerant circuit including a high-stage-side compressor, high-stage-side condenser, high-stage-side expansion valve, and high-stage-side evaporator connected by pipes, a low-stage refrigeration cycle including a low-stage-side refrigerant circuit including a low-stage-side compressor, low-stage-side condenser, low-stage-side receiver, low-stage-side expansion valve, and low-stage-side evaporator connected by pipes, a cascade condenser including the high-stage-side evaporator and low-stage-side condenser, a receiver heat exchanging portion configured to cool the low-stage-side receiver, and a high-stage refrigeration cycle controller configured to perform controlling so as to activate the high-stage-side compressor when estimating a low-stage-side refrigerant will reach a supercritical state when the low-stage-side compressor is inactive on the basis of the pressure of the low-stage-side refrigerant.
    Type: Grant
    Filed: August 5, 2013
    Date of Patent: June 19, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Keisuke Takayama, Tomotaka Ishikawa, Takeshi Sugimoto, Tetsuya Yamashita, Takashi Ikeda
  • Publication number: 20180106514
    Abstract: A refrigerating apparatus includes a high-temperature side circuit and a low-temperature side circuit connected to each other via a cascade condenser, a low-temperature side second flow control valve that turns a refrigerant, passing through a liquid pipe connecting between a cooling unit and other circuit parts in a low-temperature side circuit b, into a gas-liquid two-phase refrigerant, and an expansion tank connected to the suction side of a low-temperature circuit compressor via a tank electromagnetic valve.
    Type: Application
    Filed: November 22, 2017
    Publication date: April 19, 2018
    Inventors: Takeshi SUGIMOTO, So NOMOTO, Tomotaka ISHIKAWA, Takashi IKEDA
  • Publication number: 20180026285
    Abstract: There is provided a fuel cell system. The fuel cell system comprises a fuel cell configured to generate electric power using a reactive gas; a compressor configured to compress the reactive gas and feed the compressed reactive gas to the fuel cell; a flow rate measurement unit configured to measure a flow rate of the reactive gas; a pressure measurement unit configured to measure a pressure of the compressed reactive gas; a power value acquirer configured to acquire a value of electric power consumed by the compressor; and a determiner configured to perform determination with regard to an abnormality of the fuel cell system and to provide an output indicating that an abnormality occurs.
    Type: Application
    Filed: July 7, 2017
    Publication date: January 25, 2018
    Inventors: Tomio YAMANAKA, Tomotaka ISHIKAWA
  • Publication number: 20180026284
    Abstract: A fuel cell system comprises a fuel cell, a cooling system, a rotating speed acquisition part acquiring a rotating speed of the refrigerant pump, a power consumption acquisition part acquiring a power consumption of the refrigerant pump, and a controller configured to receive a rotating speed acquired by the rotating speed acquisition part and control the refrigerant pump. The controller has stored therein a predetermined correspondence between rotating speeds of the refrigerant pump and power consumption threshold values.
    Type: Application
    Filed: May 30, 2017
    Publication date: January 25, 2018
    Inventors: Tomoyuki NISHIDA, Tomotaka ISHIKAWA, Keitaro YAMAMORI
  • Publication number: 20180026288
    Abstract: There is provided a fuel cell system comprising a controller configured to control an opening position of a valve element of a flow dividing valve. The valve element is configured to be movable between a first position and a second position, according to the number of steps of a stepping motor that is provided to drive the valve element. When causing a fuel cell to perform power generation, the controller moves the valve element by a first number of steps such as to move from the first position to the second position and to additionally move the valve element toward the second position, based on a second number of steps that are taken from a time when the valve element starts moving from the first position toward the second position to a time when a voltage measured by a voltage sensor exceeds a predetermined value.
    Type: Application
    Filed: June 16, 2017
    Publication date: January 25, 2018
    Inventors: Tomio YAMANAKA, Tomotaka ISHIKAWA
  • Publication number: 20180026286
    Abstract: A fuel cell system comprises: a fuel gas supplier: an air supplier; an air flow rate acquirer that obtains a flow rate of the air that is supplied to a fuel cell; a voltage acquirer that obtains an output voltage of the fuel cell; and a controller. At the time of starting the fuel cell system, the controller controls the fuel gas supplier to supply a fuel gas to the fuel cell for a first time period. After elapse of the first time period, the controller controls the air supplier to start supply of the air. The controller calculates an integrated value of the flow rate for a second time period after the supply of the air is started. When the integrated value becomes greater than a predetermined amount and the output voltage is less than a predetermined voltage, the controller determines that the fuel cell system has an abnormality.
    Type: Application
    Filed: July 18, 2017
    Publication date: January 25, 2018
    Inventors: Tomio YAMANAKA, Tomotaka ISHIKAWA
  • Patent number: 9874402
    Abstract: A heat exchanger includes a plurality of fins spaced apart from each other such that gas flows therebetween, and a plurality of heat transfer tubes extending through the plurality of fins and joined to the plurality of fins by tube expansion. The heat transfer tubes are arranged in five or more columns along a flow direction of the gas and staggered in a row direction intersecting the flow direction of the gas. Each of the plurality of fins is flat and plate-shaped and continuously extends between the heat transfer tubes in the flow direction of the gas. The plurality of heat transfer tubes satisfy relationships of 1.055D?Da?1.068D and 1.56Da?L?2.58Da, where D is an unexpanded outside diameter of the heat transfer tubes, Da is an expanded outside diameter thereof, and L is a distance between centers of adjacent two heat transfer tubes.
    Type: Grant
    Filed: December 27, 2013
    Date of Patent: January 23, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Tomotaka Ishikawa, Sangmu Lee
  • Patent number: 9835368
    Abstract: A refrigerating and air-conditioning apparatus performs, even during a heating operation under air conditions leading to formation of frost, a defrosting operation while simultaneously continuing the heating operation and improves comfort through heating by securing an appropriate amount of ventilation. A plurality of refrigeration cycles independently performs a heating operation and a defrosting operation. By controlling a ventilation damper of an indoor unit that is to perform a defrosting operation to increase the amount of ventilation, a prior ventilation operation for securing the time-averaged required amount of ventilation including the period in which the defrosting operation is being performed is performed before the defrosting operation, and after the prior ventilation is terminated, the defrosting operation is started.
    Type: Grant
    Filed: September 13, 2011
    Date of Patent: December 5, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: So Nomoto, Tomotaka Ishikawa
  • Patent number: 9797648
    Abstract: A refrigerating and air-conditioning apparatus performs, even during a heating operation under air conditions leading to formation of frost, a defrosting operation while simultaneously continuing a heating operation and that improves comfort through heating by ensuring an appropriate amount of ventilation. A plurality of refrigeration cycles that are capable of independently performing a heating operation and a defrosting operation, are provided. A ventilation damper of an indoor unit in which a refrigeration cycle that performs a defrosting operation is installed is closed during a defrosting operation, and a ventilation damper of an indoor unit in which a refrigeration cycle that performs a heating operation is installed is controlled to achieve a required amount of ventilation corresponding to the indoor ventilation state.
    Type: Grant
    Filed: September 13, 2011
    Date of Patent: October 24, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Tomotaka Ishikawa, So Nomoto
  • Publication number: 20170299241
    Abstract: The refrigeration cycle apparatus includes: liquid-side connection piping that extends from liquid-side refrigerant piping; gas-side connection piping that extends from gas-side refrigerant piping; a refrigerant storage tank that stores refrigerant, an intake side thereof being connected to the liquid-side connection piping, and a discharge side thereof being connected to the gas-side connection piping; an inlet-side electromagnetic valve that is disposed on the liquid-side connection piping, and that is opened when there is no passage of electric current; an inlet-side check valve that is disposed on the liquid-side connection piping, and that allows the refrigerant to flow only toward the refrigerant storage tank; and a valve apparatus that is disposed on the gas-side connection piping, that is opened during passage of electric current to the inlet-side electromagnetic valve, and that is delayed before being shut off after passage of electric current to the inlet-side electromagnetic valve is stopped.
    Type: Application
    Filed: September 30, 2014
    Publication date: October 19, 2017
    Inventor: Tomotaka ISHIKAWA
  • Patent number: 9726420
    Abstract: A refrigerating and air-conditioning apparatus includes multiple refrigeration cycles each including a compressor, a four-way valve, an indoor heat exchanger, a pressure reducing device, and an outdoor heat exchanger which are connected by a pipe, each refrigeration cycle being configured to be capable of performing a cooling operation and a heating operation, an outdoor fan configured to send air for heat exchange with the outdoor heat exchangers of the refrigeration cycles, multiple indoor fans arranged corresponding to the respective indoor heat exchangers of the refrigeration cycles, and a controller configured to defrost the outdoor heat exchanger of the at least one refrigeration cycle, control a rotation speed of the indoor fan corresponding to the refrigeration cycle performing the defrosting operation such that a temperature of air mixed by air-sending through the indoor fans reaches a predetermined temperature.
    Type: Grant
    Filed: June 8, 2011
    Date of Patent: August 8, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Tomotaka Ishikawa, So Nomoto
  • Publication number: 20170108247
    Abstract: A refrigeration cycle apparatus includes: a low-stage refrigeration cycle including a low-stage compressor, a low-stage condenser, a low-stage pressure reducing device, and a low-stage evaporator, and circulating low-stage refrigerant; a high-stage refrigeration cycle including a high-stage compressor, a high-stage condenser, a high-stage pressure reducing device, and a high-stage evaporator, and circulating high-stage refrigerant; a cascade condenser exchanging heat between the low-stage refrigerant in the low-stage condenser and the high-stage refrigerant in the high-stage evaporator, and a controller. The low-stage refrigerant is a refrigerant that undergoes disproportionation. The low-stage refrigerant is maintained at a pressure lower than a disproportionation pressure at which the low-stage refrigerant undergoes disproportionation.
    Type: Application
    Filed: March 17, 2014
    Publication date: April 20, 2017
    Inventors: Hiroshi SATA, Tomotaka ISHIKAWA, Takashi IKEDA, Yusuke ARII
  • Publication number: 20170051956
    Abstract: An accumulator that is used in a refrigeration apparatus including a plurality of compressors and is provided for the plurality of compressors, the accumulator including an inlet pipe that penetrates a cylindrical container perpendicularly to a central axis of the cylindrical container and conveys gas-liquid mixed refrigerant into the container and a plurality of outlet pipes connected to respective suction sides of the plurality of compressors, wherein the plurality of outlet pipes each have one end located in the container and forming outlet port for conveying gas refrigerant in the container toward the plurality of compressors, and wherein the outlet port of each of the plurality of outlet pipes is concentrated in a central part of the container.
    Type: Application
    Filed: February 28, 2014
    Publication date: February 23, 2017
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: (no name) ABASTARI, Satoru UE, Tomotaka ISHIKAWA, Kenichi HATA
  • Patent number: 9541313
    Abstract: A refrigerating device that forms a refrigerating cycle in which a plurality of outdoor machines 1a and 1b provided at least with compressors 2a and 2b, condensers 4a and 4b, and accumulators 5a and 5b respectively and an indoor machine 20 provided with decompressing means 21 and an evaporator 22 are connected in parallel by piping, having oil return pipes 13a and 13b that return refrigerator oil stored in the accumulators into the compressors, an oil equalizing pipe 10 that connects the accumulators to each other, and a controller 30 that controls an operation of the compressor and on/off of an electromagnetic valve 12a deposed on the oil equalizing pipe.
    Type: Grant
    Filed: March 11, 2010
    Date of Patent: January 10, 2017
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Takashi Ikeda, Tomotaka Ishikawa, Hiroshi Sata, Fumitake Unezaki
  • Patent number: 9452770
    Abstract: A steering wheel of the present invention is provided with: a spoke cored bar portion configured to couple a boss cored bar portion and a rim cored bar portion to each other. At least a surface of a respective one of the rim cored bar portion and the spoke cored bar portion is covered with a synthetic resin. An inclined longitudinal wall portion is coupled to the spoke cored bar portion at a connection portion, and at an intermediate part of the connection portion, an easily deformable portion is formed. In this manner, it is possible to provide a steering wheel which is not degraded in appearance quality, even if a rib for preventing shrinkage of a resin is increased in size, the steering wheel having an excellent dynamic performance thereof.
    Type: Grant
    Filed: October 24, 2014
    Date of Patent: September 27, 2016
    Assignee: NIHON PLAST CO., LTD.
    Inventor: Tomotaka Ishikawa
  • Patent number: 9425473
    Abstract: The invention is provided to reliably restore generated voltage that has declined due to clogging of water in a fuel cell stack. A method of operating a fuel cell system having a fuel cell stack that generates electricity through an electrochemical reaction between a fuel gas including hydrogen gas and an oxidation gas, wherein when a generated voltage of the fuel cell stack declines, the water-in-cell content of the fuel cell stack is adjusted so that a variation in cell pressure loss in the fuel cell stack decreases based on a characteristic curve of the water-in-cell content of the fuel cell stack and the cell pressure loss of the fuel cell stack.
    Type: Grant
    Filed: July 9, 2009
    Date of Patent: August 23, 2016
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Yoshiaki Naganuma, Keigo Suematsu, Tomotaka Ishikawa, Hiroyuki Katsuda
  • Publication number: 20160025415
    Abstract: A heat exchanger includes a plurality of fins spaced apart from each other such that gas flows therebetween, and a plurality of heat transfer tubes extending through the plurality of fins and joined to the plurality of fins by tube expansion. The heat transfer tubes are arranged in five or more columns along a flow direction of the gas and staggered in a row direction intersecting the flow direction of the gas. Each of the plurality of fins is flat and plate-shaped and continuously extends between the heat transfer tubes in the flow direction of the gas. The plurality of heat transfer tubes satisfy relationships of 1.055 D?Da?1.068 D and 1.56 Da?L?2.58 Da, where D is an unexpanded outside diameter of the heat transfer tubes, Da is an expanded outside diameter thereof, and L is a distance between centers of adjacent two heat transfer tubes.
    Type: Application
    Filed: December 27, 2013
    Publication date: January 28, 2016
    Inventors: Tomotaka ISHIKAWA, Sangmu LEE
  • Patent number: 9227588
    Abstract: The present invention aims to provide a steering wheel in which a decorative member is easily mounted and fixed to a steering main body without a need to employ fixing parts such as screws, and which is capable of effectively absorbing an impact by appropriately deforming the decorative member at the time of input of a load. The steering wheel of the present invention has: a plurality of engaging fixed units by which the decorative member is mounted and fixed to the steering main body's side via a fixing unit, and demounting of the fixing unit is restrained at the time of deformation of the decorative member; and an engaging unit which is arranged on a site configured to produce a bending deformation of the decorative member, and by which demounting is disallowed to be restrained at the time of deformation of the decorative member.
    Type: Grant
    Filed: May 29, 2014
    Date of Patent: January 5, 2016
    Assignee: NIHON PLAST CO., LTD
    Inventors: Daisuke Ishioroshi, Tomotaka Ishikawa, Kazuhiro Tono
  • Patent number: 9105889
    Abstract: In order to cause a plurality of cells in a fuel cell to be recovered to a desired humidity state, it is configured to determine that the cells present a mixture of dry and overly humid states in the case where a predetermined condition is satisfied, and in the case where it is determined that the cells present the mixture, humidifying control is carried out to cause all the cells to attain the overly humid state, and thereafter, drying control is carried out to dry all the cells, to thereby cause the plurality of cells to be recovered to a predetermined humidity state.
    Type: Grant
    Filed: November 18, 2009
    Date of Patent: August 11, 2015
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Keigo Suematsu, Tomotaka Ishikawa, Yoshiaki Naganuma, Hiroyuki Katsuda