Patents by Inventor Shinobu OIKAWA

Shinobu OIKAWA 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: 9534589
    Abstract: Between a movable core chamber and a fuel supply passage, a needle guide slidably supports a needle fixed to a movable core. The needle guide has a communication hole which fluidly connects the movable core chamber and the fuel supply passage. An opening sectional area of the communication hole is defined in such a manner that a fuel discharged amount decreases as an energization start time of a coil is delayed. In a suction stroke, it is restricted that the movable core and the needle bounce toward the fixed core after the needle biases a suction valve toward a stopper by means of a biasing force of a second spring. A relationship between the energization start time of the coil and the fuel discharged amount is properly maintained, so that the fuel discharged amount of the high-pressure pump can be controlled correctly.
    Type: Grant
    Filed: July 2, 2013
    Date of Patent: January 3, 2017
    Assignees: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Shinobu Oikawa, Hirokuni Tomita, Takehiko Kato
  • Patent number: 9404481
    Abstract: Between a movable core chamber and a fuel supply passage, a needle guide slidably supports a needle fixed to a movable core. The needle guide has a communication hole which fluidly connects the movable core chamber and the fuel supply passage. An opening sectional area of the communication hole is defined in such a manner that a fuel discharged amount decreases as an energization start time of a coil is delayed. In a suction stroke, it is restricted that the movable core and the needle bounce toward the fixed core after the needle biases a suction valve toward a stopper by means of a biasing force of a second spring. A relationship between the energization start time of the coil and the fuel discharged amount is properly maintained, so that the fuel discharged amount of the high-pressure pump can be controlled correctly.
    Type: Grant
    Filed: November 17, 2015
    Date of Patent: August 2, 2016
    Assignees: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Shinobu Oikawa, Hirokuni Tomita, Takehiko Kato
  • Patent number: 9388780
    Abstract: A resilient member is accommodated within a single support column, which connects a flange and a pump unit. The resilient member presses the pump unit in an axial direction toward a bottom part of a fuel tank through a holder member. The support column is formed in a polygonal tube shape and has a specific range in a part in the axial direction. A peripheral wall in the specific range is concave relative to corner parts of peripheral walls in an outside of the specific range so that a longitudinal groove having a groove bottom is provided to separate an inside and an outside of the support column. The holder member holding the pump unit is formed in a polygonal hole shape to be fitted with the peripheral walls. The holder member has a slide protrusion, which slidingly moves in the longitudinal groove in a state that the holder member is pushed into the longitudinal groove from the outside of the support column.
    Type: Grant
    Filed: April 11, 2014
    Date of Patent: July 12, 2016
    Assignee: DENSO CORPORATION
    Inventors: Shinobu Oikawa, Tetsuro Okazono
  • Patent number: 9328723
    Abstract: A valve member of a pressure relief valve has a shaft portion, a pressure receiving portion, and a guide portion, wherein the valve member is axially movable in a fuel return passage. When a forward end of the shaft portion is seated on a valve seta, the fuel return passage is closed, while the shaft portion is separated from the valve seat the fuel return passage is opened. A notched portion is formed at an outer wall of the guide portion to thereby form an outer-surface passage. A fuel inlet port is formed in the valve member for communicating a fuel inlet chamber to the fuel return passage at a downstream side of the valve member.
    Type: Grant
    Filed: March 5, 2014
    Date of Patent: May 3, 2016
    Assignee: DENSO CORPORATION
    Inventors: Shinobu Oikawa, Yoshinori Yamashita, Katsunori Furuta, Masayuki Kobayashi, Shigeto Tsuge
  • Publication number: 20160115953
    Abstract: A high-pressure pump is comprised of a lower housing, an upper housing and a cover, which are formed independently from each other. Thereby, shapes of the above can be simplified. Although the cylinder and the plunger receive a fuel pressure during a pressurization stroke, the upper housing and the cover do not receive fuel pressure directly from a pressurization chamber. Therefore, the upper housing and the cover can be made thin and light as much as possible.
    Type: Application
    Filed: January 6, 2016
    Publication date: April 28, 2016
    Inventors: Masatoshi Kuroyanagi, Mamoru Urushizaki, Yasuaki Matsunaga, Shinobu Oikawa, Noriya Matsumoto
  • Publication number: 20160069333
    Abstract: Between a movable core chamber and a fuel supply passage, a needle guide slidably supports a needle fixed to a movable core. The needle guide has a communication hole which fluidly connects the movable core chamber and the fuel supply passage. An opening sectional area of the communication hole is defined in such a manner that a fuel discharged amount decreases as an energization start time of a coil is delayed. In a suction stroke, it is restricted that the movable core and the needle bounce toward the fixed core after the needle biases a suction valve toward a stopper by means of a biasing force of a second spring. A relationship between the energization start time of the coil and the fuel discharged amount is properly maintained, so that the fuel discharged amount of the high-pressure pump can be controlled correctly.
    Type: Application
    Filed: November 17, 2015
    Publication date: March 10, 2016
    Inventors: Shinobu OIKAWA, Hirokuni TOMITA, Takehiko KATO
  • Patent number: 9261061
    Abstract: A high-pressure pump is comprised of a lower housing, an upper housing and a cover, which are formed independently from each other. Thereby, shapes of the above can be simplified. Although the cylinder and the plunger receive a fuel pressure during a pressurization stroke, the upper housing and the cover do not receive fuel pressure directly from a pressurization chamber. Therefore, the upper housing and the cover can be made thin and light as much as possible.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: February 16, 2016
    Assignee: DENSO CORPORATION
    Inventors: Masatoshi Kuroyanagi, Mamoru Urushizaki, Yasuaki Matsunaga, Shinobu Oikawa, Noriya Matsumoto
  • Publication number: 20160025054
    Abstract: A valve body is provided with a discharge relief portion. A relief valve outlet is formed in an end face thereof on a central axis of the valve body. Discharge valve inlets are point-symmetrically formed with respect to the central axis. A discharge valve outlet is formed in another end face thereof and relief valve inlets are point-symmetrically formed with respect to the central axis. A discharge valve outlet and the discharge valve inlets communicate with each other. A flow of fuel from a pressurization chamber to a fuel discharge port is restricted by a discharge valve member capable of closing the discharge valve outlet. The relief valve outlet and the relief valve inlets communicate with each other. A flow of fuel from the fuel discharge port to the pressurization chamber is restricted by a relief valve member capable of closing the relief valve outlet.
    Type: Application
    Filed: October 1, 2015
    Publication date: January 28, 2016
    Inventors: Masatoshi KUROYANAGI, Shinobu OIKAWA, Tatsuro KOGA
  • Patent number: 9181944
    Abstract: A valve body is provided with a discharge relief portion. A relief valve outlet is formed in an end face thereof on a central axis of the valve body. Discharge valve inlets are point-symmetrically formed with respect to the central axis. A discharge valve outlet is formed in another end face thereof and relief valve inlets are point-symmetrically formed with respect to the central axis. A discharge valve outlet and the discharge valve inlets communicate with each other. A flow of fuel from a pressurization chamber to a fuel discharge port is restricted by a discharge valve member capable of closing the discharge valve outlet. The relief valve outlet and the relief valve inlets communicate with each other. A flow of fuel from the fuel discharge port to the pressurization chamber is restricted by a relief valve member capable of closing the relief valve outlet.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: November 10, 2015
    Assignee: DENSO CORPORATION
    Inventors: Masatoshi Kuroyanagi, Shinobu Oikawa, Tatsuro Koga
  • Patent number: 9115713
    Abstract: A high-pressure pump includes a plunger for pressurizing a fuel, a cylinder accommodating the plunger reciprocatably in its axial direction and a pump body. The pump body defines a pressurization chamber, a low-pressure fuel passage hydraulically connecting a fuel inlet and the pressurization chamber, and a discharge passage. The pump body further defines a cylindrical space around the cylinder. The fuel flows into the cylindrical space from the low-pressure fuel passage so as to cool the cylinder. The entire outer surface of the cylinder can be surely cooled.
    Type: Grant
    Filed: April 8, 2011
    Date of Patent: August 25, 2015
    Assignee: DENSO CORPORATION
    Inventor: Shinobu Oikawa
  • Patent number: 9109593
    Abstract: A high-pressure pump has: a plunger; a pump body; a cover member for covering the pump body and forming a fuel chamber; a pulsation damper body constructed of upper and lower diaphragms with their peripheral edge portions joined and for reducing pressure pulsation in the chamber, the upper and lower diaphragms trapping gas having a given pressure between them; an upper support member having an upper ring-shaped part and an upper support body, the upper ring-shaped part being joined to the peripheral edge portion of the upper diaphragm, the upper support body extending from the upper ring-shaped part and abutting on the cover member; and a lower support member having a lower ring-shaped part and a lower support body, the lower ring-shaped part being joined to the peripheral edge portion of the lower diaphragm, the lower support body extending from the lower ring-shaped part and abutting on the pump body.
    Type: Grant
    Filed: August 15, 2012
    Date of Patent: August 18, 2015
    Assignee: DENSO CORPORATION
    Inventors: Shinobu Oikawa, Takayuki Watanabe, Hiroshi Inoue
  • Patent number: 8992190
    Abstract: A reservoir is in a bottomed tubular shape and located in a fuel tank. A lid member closes an opening of the reservoir. A pump unit discharges fuel stored in the reservoir to an exterior of the fuel tank. The pump unit is supported by a holding portion of the lid member.
    Type: Grant
    Filed: September 12, 2011
    Date of Patent: March 31, 2015
    Assignees: Denso Corporation, Kyosan Denki Co., Ltd.
    Inventors: Tetsuro Okazono, Shinobu Oikawa, Hironobu Oki
  • Publication number: 20150078922
    Abstract: A high pressure pump includes a pump body, a pressurizing chamber, a fuel passage, a union, a seat member, a relief valve seat, a relief valve, a discharge valve seat, a discharge valve, a spring and a spring holder. The union has an inner threaded portion and a step portion formed on an inner wall of the union. The seat member includes a relief passage that extends through the seat member in an axial direction of the seat member and a discharge path that is not in fluid communication with the relief passage. The one opening of the relief passage is closer to the pressurizing chamber than an other opening of the relief passage is to the pressurizing chamber. The one opening of the discharge path is further from the pressurizing chamber than an other opening of the discharge path is from the pressurizing chamber. The seat member is pressed toward the step portion when the spring holder is fastened to the union by engaging the inner threaded portion with the outer threaded portion.
    Type: Application
    Filed: August 22, 2014
    Publication date: March 19, 2015
    Inventors: Shinobu OIKAWA, Masatoshi KUROYANAGI
  • Patent number: 8955550
    Abstract: A damper device includes a first diaphragm having a first peripheral part, a second diaphragm having a second peripheral part, a first support portion disposed on the opposite side from the second peripheral part with respect to the first peripheral part, and a second support portion disposed on the opposite side from the first peripheral part with respect to the second peripheral part. The first peripheral part and the second peripheral part are supported between the first support portion and the second support portion. Radially outer sections of the first peripheral part, the second peripheral part, the first support portion, and the second support portion are integrally welded with each other.
    Type: Grant
    Filed: April 11, 2013
    Date of Patent: February 17, 2015
    Assignee: Denso Corporation
    Inventor: Shinobu Oikawa
  • Publication number: 20140360602
    Abstract: A resilient member is accommodated within a single support column, which connects a flange and a pump unit. The resilient member presses the pump unit in an axial direction toward a bottom part of a fuel tank through a holder member. The support column is formed in a polygonal tube shape and has a specific range in a part in the axial direction. A peripheral wall in the specific range is concave relative to corner parts of peripheral walls in an outside of the specific range so that a longitudinal groove having a groove bottom is provided to separate an inside and an outside of the support column. The holder member holding the pump unit is formed in a polygonal hole shape to be fitted with the peripheral walls. The holder member has a slide protrusion, which slidingly moves in the longitudinal groove in a state that the holder member is pushed into the longitudinal groove from the outside of the support column.
    Type: Application
    Filed: April 11, 2014
    Publication date: December 11, 2014
    Applicant: DENSO CORPORATION
    Inventors: Shinobu OIKAWA, Tetsuro OKAZONO
  • Patent number: 8881765
    Abstract: A reservoir is located in a fuel tank. The reservoir is in a bottomed tubular shape having a periphery defining an opening. A lid member is located in the fuel tank and mounted to the periphery of the reservoir to close the opening. A pump unit is partially accommodated in the reservoir to discharge fuel stored in the reservoir to an exterior of the fuel tank. The pump unit is located at a position offset from a center axis of the lid member. The pump unit has a projection projected from the lid member to an exterior of the reservoir. A remaining quantity detector is configured to detect a quantity of fuel in the fuel tank. The remaining quantity detector is located at a remaining space remaining in the fuel tank. The remaining space is located on the lid member and located around the projection.
    Type: Grant
    Filed: September 12, 2011
    Date of Patent: November 11, 2014
    Assignees: Denso Corporation, Kyosan Denki Co., Ltd.
    Inventors: Tetsuro Okazono, Shinobu Oikawa, Hironobu Oki
  • Publication number: 20140314605
    Abstract: A common seat portion includes discharge passages that communicate between a first valve chamber and a second valve chamber when a discharge valve member is lifted away from the common seat portion. The common seat portion also includes a relief passage that extends substantially parallel to the discharge passages and communicates between the first valve chamber and the second valve chamber when a relief valve member is lifted away from the common seat portion.
    Type: Application
    Filed: April 16, 2014
    Publication date: October 23, 2014
    Applicants: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Tatsuro KOGA, Ichiki TERASHIMA, Toshihide ONO, Seiji TANIZAWA, Takehiko KATO, Masatoshi KUROYANAGI, Shinobu OIKAWA, Noriya MATSUMOTO
  • Publication number: 20140182451
    Abstract: A valve member of a pressure relief valve has a shaft portion, a pressure receiving portion, and a guide portion, wherein the valve member is axially movable in a fuel return passage. When a forward end of the shaft portion is seated on a valve seta, the fuel return passage is closed, while the shaft portion is separated from the valve seat the fuel return passage is opened. A notched portion is formed at an outer wall of the guide portion to thereby form an outer-surface passage. A fuel inlet port is formed in the valve member for communicating a fuel inlet chamber to the fuel return passage at a downstream side of the valve member.
    Type: Application
    Filed: March 5, 2014
    Publication date: July 3, 2014
    Applicant: DENSO CORPORATION
    Inventors: Shinobu OIKAWA, Yoshinori Yamashita, Katsunori Furuta, Masayuki Kobayashi, Shigeto Tsuge
  • Patent number: 8701631
    Abstract: A valve member of a pressure relief valve has a shaft portion, a pressure receiving portion, and a guide portion, wherein the valve member is axially movable in a fuel return passage. When a forward end of the shaft portion is seated on a valve seta, the fuel return passage is closed, while the shaft portion is separated from the valve seat the fuel return passage is opened. A notched portion is formed at an outer wall of the guide portion to thereby form an outer-surface passage. A fuel inlet port is formed in the valve member for communicating a fuel inlet chamber to the fuel return passage at a downstream side of the valve member.
    Type: Grant
    Filed: June 16, 2011
    Date of Patent: April 22, 2014
    Assignee: Denso Corporation
    Inventors: Shinobu Oikawa, Yoshinori Yamashita, Katsunori Furuta, Masayuki Kobayashi, Shigeto Tsuge
  • Patent number: 8689827
    Abstract: A support shaft connects between a flange and a pump unit. An intermediate member, which connects between the support shaft and pump unit, enables a relative positional change between the support shaft and the pump unit in an axial direction of the support shaft. The intermediate member limits a relative positional change between the support shaft and the pump unit in a circumferential direction of the support shaft. A resilient member is received in the support shaft and exerts a restoring force in an axial direction of the support shaft to urge the pump unit, which is movable relative to the support shaft in the axial direction, toward a bottom portion of the fuel tank.
    Type: Grant
    Filed: September 12, 2011
    Date of Patent: April 8, 2014
    Assignees: Denso Corporation, Kyosan Denki Co., Ltd.
    Inventors: Tetsuro Okazono, Shinobu Oikawa, Kiyomori Kobayashi, Norihiro Hayashi, Shinji Noda, Hiroshi Morishita, Kazuki Matsubara, Kouji Maruyama, Masato Inoue, Hironobu Oki