Patents by Inventor Takehiko Asada

Takehiko Asada 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: 11433229
    Abstract: A pressure relief valve for a reservoir has a main body with a central chamber defining an outer radial seat, a positive-pressure port with an inner radial seat, and a negative-pressure port comprising an internal passage spanning the outer seat. The sealing disk has an anchor body retained in the central chamber and a flexible diaphragm biased against the outer seat. An axial passage in the anchor body couples the central chamber to ambient atmospheric pressure. The sealing ball is biased against the inner seat. When a pressure inside the reservoir exceeds ambient by a positive-pressure threshold, then the sealing ball lifts off the inner radial seat to exhaust a gas through the positive-pressure port. When the pressure inside the reservoir is below ambient by a negative-pressure threshold, then the diaphragm is lifted off the outer seat to intake atmospheric gas into the reservoir.
    Type: Grant
    Filed: June 3, 2020
    Date of Patent: September 6, 2022
    Assignee: TERUMO CARDIOVASCULAR SYSTEMS CORPORATION
    Inventor: Takehiko Asada
  • Publication number: 20210381612
    Abstract: A pressure relief valve for a reservoir has a housing body forming first and second subchambers in fluid communication. A first opening in a bottom surface of the housing body forms a first valve seat. At least one second opening in the bottom surface forms a second valve seat along an outer perimeter. A diaphragm member is biased against the second valve seat and is configured to deflect off of the second valve seat under a negative pressure. A sealing ball is gravitationally biased against the first valve seat and raises off the first valve seat in response to a positive pressure. A cover sheet on an upper surface of the housing body partially encloses the chamber and traps the sealing ball in the first subchamber. The cover sheet includes an aperture aligned with the second subchamber providing an ambient pressure port coupled to ambient atmosphere.
    Type: Application
    Filed: November 9, 2020
    Publication date: December 9, 2021
    Inventors: Takehiko Asada, Ryan Clingman, Stephen Koellhoffer, Luke Powers
  • Publication number: 20210379351
    Abstract: A pressure relief valve for a reservoir has a main body with a central chamber defining an outer radial seat, a positive-pressure port with an inner radial seat, and a negative-pressure port comprising an internal passage spanning the outer seat. The sealing disk has an anchor body retained in the central chamber and a flexible diaphragm biased against the outer seat. An axial passage in the anchor body couples the central chamber to ambient atmospheric pressure. The sealing ball is biased against the inner seat. When a pressure inside the reservoir exceeds ambient by a positive-pressure threshold, then the sealing ball lifts off the inner radial seat to exhaust a gas through the positive-pressure port. When the pressure inside the reservoir is below ambient by a negative-pressure threshold, then the diaphragm is lifted off the outer seat to intake atmospheric gas into the reservoir.
    Type: Application
    Filed: June 3, 2020
    Publication date: December 9, 2021
    Inventor: Takehiko Asada
  • Patent number: 11191943
    Abstract: A pressure relief valve for a reservoir has a housing body forming first and second subchambers in fluid communication. A first opening in a bottom surface of the housing body forms a first valve seat. At least one second opening in the bottom surface forms a second valve seat along an outer perimeter. A diaphragm member is biased against the second valve seat and is configured to deflect off of the second valve seat under a negative pressure. A sealing ball is gravitationally biased against the first valve seat and raises off the first valve seat in response to a positive pressure. A cover sheet on an upper surface of the housing body partially encloses the chamber and traps the sealing ball in the first subchamber. The cover sheet includes an aperture aligned with the second subchamber providing an ambient pressure port coupled to ambient atmosphere.
    Type: Grant
    Filed: November 9, 2020
    Date of Patent: December 7, 2021
    Assignee: TERUMO CARDIOVASCULAR SYSTEMS CORPORATION
    Inventors: Takehiko Asada, Ryan Clingman, Stephen Koellhoffer, Luke Powers
  • Patent number: 8430652
    Abstract: A blood pump apparatus comprises a housing, a centrifugal pump section including an impeller and rotating inside the housing to feed a fluid by a centrifugal force, an impeller rotational torque generation section for attracting thereto said impeller and rotating said impeller; and a plurality of grooves for hydrodynamic bearing provided on an inner surface of said housing at a side of said impeller rotational torque generation section, each of the grooves for hydrodynamic bearing having a first side and a second side both extending from a periphery of said portion in which a groove for hydrodynamic bearing is formed toward a central side thereof and opposed to each other, a third side connecting one end of said first side and one end of said second side to each other, and a fourth side connecting said other end of said first side and said other end of said second side to each other; said first side and said second side are formed as a circular arc respectively in such a way that centers of said circular arcs
    Type: Grant
    Filed: May 17, 2010
    Date of Patent: April 30, 2013
    Assignees: Terumo Kabushiki Kaisha, NTN Corporation
    Inventors: Mitsutoshi Yaegashi, Takehiko Asada, Takehisa Mori, Takayoshi Ozaki, Kenichi Suzuki
  • Publication number: 20100221130
    Abstract: A blood pump apparatus comprises a housing, a centrifugal pump section including an impeller and rotating inside the housing to feed a fluid by a centrifugal force, an impeller rotational torque generation section for attracting thereto said impeller and rotating said impeller; and a plurality of grooves for hydrodynamic bearing provided on an inner surface of said housing at a side of said impeller rotational torque generation section, each of the grooves for hydrodynamic bearing having a first side and a second side both extending from a periphery of said portion in which a groove for hydrodynamic bearing is formed toward a central side thereof and opposed to each other, a third side connecting one end of said first side and one end of said second side to each other, and a fourth side connecting said other end of said first side and said other end of said second side to each other; said first side and said second side are formed as a circular arc respectively in such a way that centers of said circular arcs
    Type: Application
    Filed: May 17, 2010
    Publication date: September 2, 2010
    Applicants: TERUMO KABUSHIKI KAISHA, NTN CORPORATION
    Inventors: Mitsutoshi Yaegashi, Takehiko Asada, Takehisa Mori, Takayoshi Ozaki, Kenichi Suzuki
  • Patent number: 7748964
    Abstract: A blood pump apparatus comprises a housing, a centrifugal pump section including an impeller and rotating inside the housing to feed a fluid by a centrifugal force, an impeller rotational torque generation section for attracting thereto said impeller and rotating said impeller; and a plurality of grooves for hydrodynamic bearing provided on an inner surface of said housing at a side of said impeller rotational torque generation section, each of the grooves for hydrodynamic bearing having a first side and a second side both extending from a periphery of said portion in which a groove for hydrodynamic bearing is formed toward a central side thereof and opposed to each other, a third side connecting one end of said first side and one end of said second side to each other, and a fourth side connecting said other end of said first side and said other end of said second side to each other; said first side and said second side are formed as a circular arc respectively in such a way that centers of said circular arcs
    Type: Grant
    Filed: March 24, 2005
    Date of Patent: July 6, 2010
    Assignees: Terumo Kabushiki Kaisha, NTN Corporation
    Inventors: Mitsutoshi Yaegashi, Takehiko Asada, Takehisa Mori, Takayoshi Ozaki, Kenichi Suzuki
  • Publication number: 20050287022
    Abstract: A blood pump apparatus comprises a housing, a centrifugal pump section including an impeller and rotating inside the housing to feed a fluid by a centrifugal force, an impeller rotational torque generation section for attracting thereto said impeller and rotating said impeller; and a plurality of grooves for hydrodynamic bearing provided on an inner surface of said housing at a side of said impeller rotational torque generation section, each of the grooves for hydrodynamic bearing having a first side and a second side both extending from a periphery of said portion in which a groove for hydrodynamic bearing is formed toward a central side thereof and opposed to each other, a third side connecting one end of said first side and one end of said second side to each other, and a fourth side connecting said other end of said first side and said other end of said second side to each other; said first side and said second side are formed as a circular arc respectively in such a way that centers of said circular arcs
    Type: Application
    Filed: March 24, 2005
    Publication date: December 29, 2005
    Applicants: TERUMO KABUSHIKI KAISHA, NTN CORPORATION
    Inventors: Mitsutoshi Yaegashi, Takehiko Asada, Takehisa Mori, Takayoshi Ozaki, Kenichi Suzuki
  • Patent number: 6840735
    Abstract: A centrifugal fluid pump apparatus includes a control mechanism; and a body 5 including a pump section having an impeller rotating inside a housing; a rotor having an impeller attraction magnet; a motor for rotating the rotor; an impeller attraction electromagnet for attracting the impeller thereto; an impeller-position detection sensor; and a groove for hydrodynamic bearing provided on an inner surface of the housing. The control mechanism has a position sensor output monitoring function or an electromagnet current monitoring function, a motor current monitoring function; and an emergency impeller rotation function. The impeller rotation function operates when the sensors or the electromagnet has a failure by using the position sensor output monitoring function or the electromagnet current monitoring function to rotate the impeller by utilizing the groove for hydrodynamic bearing.
    Type: Grant
    Filed: January 9, 2003
    Date of Patent: January 11, 2005
    Assignee: Terumo Kabushiki Kaisha
    Inventors: Mitsutoshi Yaegashi, Takehiko Asada
  • Publication number: 20030152462
    Abstract: A centrifugal fluid pump apparatus includes a control mechanism; and a body 5 including a pump section having an impeller rotating inside a housing; a rotor having an impeller attraction magnet; a motor for rotating the rotor; an impeller attraction electromagnet for attracting the impeller thereto; an impeller-position detection sensor; and a groove for hydrodynamic bearing provided on an inner surface of the housing. The control mechanism has a position sensor output monitoring function or an electromagnet current monitoring function, a motor current monitoring function; and an emergency impeller rotation function. The impeller rotation function operates when the sensors or the electromagnet has a failure by using the position sensor output monitoring function or the electromagnet current monitoring function to rotate the impeller by utilizing the groove for hydrodynamic bearing.
    Type: Application
    Filed: January 9, 2003
    Publication date: August 14, 2003
    Inventors: Mitsutoshi Yaegashi, Takehiko Asada