Patents by Inventor Kenichiro Tokuo

Kenichiro Tokuo 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: 10753357
    Abstract: A fuel pump includes an intake valve unit which is provided between a low-pressure chamber and a pressurizing chamber. The intake valve unit includes an intake valve configured to move in an axial direction of the intake valve unit and a valve stopper arranged between the intake valve and the pressurizing chamber. A plurality of fuel passages configured to allow fuel to communicate between the low-pressure chamber and the pressurizing chamber are formed on a radially outward of an outer peripheral surface of the valve stopper.
    Type: Grant
    Filed: September 15, 2017
    Date of Patent: August 25, 2020
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Satoshi Usui, Kenichiro Tokuo, Tatsuo Kawano, Masahiko Hayatani, Shingo Tamura, Hiroyuki Yamada, Katsumi Miyazaki
  • Publication number: 20200248663
    Abstract: To provide a high-pressure fuel pump capable of ensuring good magnetic properties and reliability for cracking. Therefore, the fixed core 39 is precipitation hardening type ferritic stainless steel (ferritic precipitation hardening type metal). The anchor 36 is precipitation hardening type ferritic stainless steel attracted by the magnetic attraction force of the fixed core 39. The outer core 38 has an inner peripheral surface on which the outer peripheral surface of the anchor 36 slides. The seal ring 48 is formed of a material having hardness lower than that of the fixed core 39 and the anchor 36, and connects the fixed core 39 and the outer core 38.
    Type: Application
    Filed: October 29, 2018
    Publication date: August 6, 2020
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Kenichiro TOKUO, Satoshi USUI, Ryo KUSAKABE
  • Patent number: 10731615
    Abstract: Responsiveness of an electromagnetic flow-rate control valve provided for closing a suction valve is improved and a discharge flow rate is controlled to a desired value. A flow-rate control valve includes a fixed core arranged on an inner circumferential side of a coil, a yoke arranged on an outer circumferential side of the coil, and a cover portion opposed to the coil in an axial direction, in which the fixed core has an enlarged portion in contact with the cover portion in the axial direction and enlarging toward the coil, and the cover portion is regulated in the axial direction only by a contact portion with the fixed core.
    Type: Grant
    Filed: June 3, 2016
    Date of Patent: August 4, 2020
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Ryo Kusakabe, Kenichiro Tokuo, Satoshi Usui, Minoru Hashida, Masayuki Suganami, Atsushi Hohkita, Eiichi Kubota, Daisuke Kitajima, Hiroshi Horie
  • Patent number: 10731616
    Abstract: A high-pressure fuel supply pump comprising a suction valve disposed on a suction side of a pressurizing chamber, an engagement member having a protrusion part that protrudes toward the outer periphery and biasing the suction valve by use of the force of a spring, a stator for generating a magnetic attraction force, and a plunger drawn by the magnetic attraction force and driving the engagement member toward the stator by engaging with the protrusion part, the fuel supply pump being configured so that the area of the fuel passage is smallest between the outer periphery of the protrusion part and the inner periphery of the plunger, and so that a tapered section whereby the area of the flow path increases from the portion where the area of the passage is smallest toward the pressurizing chamber or toward the suction valve side is formed.
    Type: Grant
    Filed: August 2, 2017
    Date of Patent: August 4, 2020
    Assignee: Hitachi Automotive Systems Ltd.
    Inventors: Yuitsu Kodama, Yukihiro Yoshinari, Kenichiro Tokuo, Yuuki Takahashi
  • Patent number: 10655585
    Abstract: A high-pressure fuel supply pump includes a pressurizing chamber, a piston plunger, and an electromagnetically-driven intake valve mechanism. The piston plunger reciprocates within the pressurizing chamber. The electromagnetically-driven intake valve mechanism is provided at an inlet of the pressurizing chamber. The electromagnetically-driven intake valve mechanism includes an anchor which pulls a plunger rod, a fixed core which attracts the anchor, and a yoke in which inner peripheral part has the fixed core and the anchor. The fixed core is fixed to a bottom part of the yoke. A through hole is formed at a bottom part of the fixed core.
    Type: Grant
    Filed: August 13, 2018
    Date of Patent: May 19, 2020
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Satoshi Usui, Kenichiro Tokuo, Tatsuo Kawano, Masahiko Hayatani, Shingo Tamura, Hiroyuki Yamada, Katsumi Miyazaki
  • Publication number: 20200080526
    Abstract: An object of the present invention is to prevent generation of wear at a rod collision portion in an electromagnetic intake valve of a high-pressure fuel supply pump by reducing inclinations of the intake valve and a rod. A structure of the electromagnetic intake valve of the high-pressure fuel supply pump is configured as follows. A seat portion of an intake valve and a guide portion of a rod are configured as an integral part, and further, a rod guide is made to have a sufficiently long length so that it is possible to perform guide at one portion. Further, the intake valve seat portion and a surface where the rod collides with the intake valve are formed on the same plane.
    Type: Application
    Filed: November 16, 2017
    Publication date: March 12, 2020
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Tatsuo KAWANO, Kenichiro TOKUO, Satoshi USUI, Masamichi YAGAI, Kazuaki TOKUMARU
  • Patent number: 10584668
    Abstract: Provide is a high-pressure fuel pump capable of improving the degree of freedom of layout of members to be attached to a pump body and a producing method thereof. Therefore, the high-pressure fuel pump includes the suction joint that sucks fuel, the pump body formed with the pressurizing chamber that pressurizes the fuel sucked from the suction joint, and the discharge joint that discharges the fuel pressurized in the pressurizing chamber. The pump body is formed so that at least a part of the side surface portion thereof becomes a cylindrical portion or a polygonal shape portion. At least one of the discharge joint and the suction joint may be fixed on the inner peripheral side with respect to the outermost peripheral portion of the cylindrical portion or the polygonal shape portion of the side surface portion.
    Type: Grant
    Filed: July 25, 2016
    Date of Patent: March 10, 2020
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Satoshi Usui, Atsushi Hohkita, Masayuki Suganami, Kenichiro Tokuo, Minoru Hashida, Masamichi Yagai, Yuta Saso, Kazuaki Tokumaru, Atsuji Saito
  • Publication number: 20200049116
    Abstract: Provided is a high-pressure fuel pump which can fix a cylinder to a pump body using a simple structure, and can reduce a displacement amount inward in a radial direction of the cylinder. A high-pressure fuel pump includes a pump body which is formed with a pressing chamber and a cylinder which is inserted in a hole formed in the pump body. The cylinder is swaged to the hole by pressing a convex portion on an outside in a radial direction to fit into the hole on an opposite side to the pressing chamber, by screwing a formed screw thread into the hole, or by being swaged with the opposite side to the pressing chamber. The cylinder is formed with a clearance in the radial direction with respect to the hole of the pump body all over a region from a bonding portion to an upper end.
    Type: Application
    Filed: March 26, 2018
    Publication date: February 13, 2020
    Inventors: Kazuaki TOKUMARU, Masahiko HAYATANI, Satoshi USUI, Atsuji SAITO, Kenichiro TOKUO, Masamichi YAGAI, Masayuki SUGANAMI
  • Publication number: 20190323465
    Abstract: An object of the present invention is to supply a high-pressure fuel supply pump capable of holding a spring holding member while reducing the height of the pump body. A high-pressure fuel supply pump is provided with a pump body for forming a pressurizing chamber at an inner wall portion, and a flange portion for fixing the pump body to a high-pressure fuel supply pump mounting portion. The high-pressure fuel supply pump is provided with a cylinder and a spring holding member. The cylinder is inserted into a hole portion of the pump body from a lower side and in which the pressurizing chamber is formed further above an uppermost end surface. The spring holding member has an outer peripheral portion press-fitted and fixed to the pump body and a holding portion holding a spring portion for biasing the pump body between the outer peripheral portion and the inner peripheral portion.
    Type: Application
    Filed: October 26, 2017
    Publication date: October 24, 2019
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Atsuji SAITO, Satoshi USUI, Minoru HASHIDA, Masayuki SUGANAMI, Hiroyuki YAMADA, Kenichiro TOKUO, Masamichi YAGAI, Yuta SASO
  • Publication number: 20190316558
    Abstract: An object of the present invention is to provide a high-pressure fuel supply pump that can restrict lowering of pressure and generation of cavitation in the vicinity of a seat by providing a throttle in a relief spring holder. Accordingly, in order to achieve the above object, the present invention relates to a fuel supply pump that includes a pressurizing chamber configured to pressurize fuel, and a relief valve mechanism configured to return fuel in a discharge path on a downstream side of the discharge valve to the pressurizing chamber. The relief valve mechanism includes a relief seat configured to close a relief channel when a relief valve is seated, a relief spring configured to energize the relief valve to the relief seat, and a relief spring holder configured to hold the relief spring. In the relief spring holder, a throttle section is formed in a fuel path for returning from a relief chamber in which the relief spring is disposed to the pressurizing chamber and the channel.
    Type: Application
    Filed: June 20, 2017
    Publication date: October 17, 2019
    Inventors: Masahiko HAYATANI, Kenichiro TOKUO, Yuta SASO, Satoshi USUI, Katsutoshi KOBAYASHI
  • Publication number: 20190301414
    Abstract: Provided is a high-pressure fuel supply pump capable of arranging a relief valve mechanism inside a pump body while suppressing an increase in size and an increase in manufacturing cost. Therefore, a high-pressure fuel supply pump of the present invention includes: a plunger that changes a volume of a pressurizing chamber by reciprocating an inside of a cylinder; a first hole formed from an outer circumferential surface of a pump body toward an inner circumferential side; a relief valve mechanism arranged in the first hole; and a second hole that returns fuel in a flow path on a discharge side of a discharge valve pressurized in the pressurizing chamber to a damper chamber or a plunger seal chamber communicating with the damper chamber when the relief valve mechanism opens in communication with the first hole.
    Type: Application
    Filed: April 11, 2017
    Publication date: October 3, 2019
    Inventors: Satoshi USUI, Atsuji SAITO, Minoru HASHIDA, Masamichi YAGAI, Kenichiro TOKUO, Masayuki SUGANAMI, Masahiko HAYATANI, Hiroyuki YAMADA
  • Patent number: 10378524
    Abstract: A high-pressure fuel pump capable of reducing the number of components and decreasing the manufacturing cost by processing of a pump body is provided. The high-pressure fuel pump includes a metal damper, a pump body in which a damper housing that houses the metal damper is formed, a damper cover attached to the pump body, covering the damper housing, and holding the metal damper between the pump body and the damper cover, and a holding member fixed to the damper cover and holding the metal damper from a side opposite to the damper cover. The holding member is provided with an elastic portion that urges the pump body so that the metal damper is urged toward the damper cover.
    Type: Grant
    Filed: June 13, 2016
    Date of Patent: August 13, 2019
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Atsuji Saito, Satoshi Usui, Masamichi Yagai, Minoru Hashida, Masayuki Suganami, Kenichiro Tokuo, Atsushi Hohkita, Yuta Saso, Kazuaki Tokumaru
  • Publication number: 20190234359
    Abstract: It is an object of the present invention to provide a control method of a high-pressure fuel supply pump and a high-pressure fuel supply pump using the same capable of effectively reducing noise generated when an electromagnetic suction valve is opened. This can be realized such that, in a control method of a high-pressure fuel supply pump including a suction valve disposed on the suction side of the pressurizing chamber, a rod for urging the suction valve toward the opening valve direction, and an anchor for moving the rod in the closing valve direction with attraction by magnetic attraction caused by a solenoid being energized, when the anchor moves in the opening valve direction, a first drive current is passed through the solenoid for a predetermined period of time, and thereafter a second drive current larger than the first drive current is passed through the solenoid for a predetermined period of time.
    Type: Application
    Filed: November 7, 2016
    Publication date: August 1, 2019
    Inventors: Masanori WATANABE, Shunsuke ARITOMI, Kenichiro TOKUO, Masayuki SUGANAMI
  • Publication number: 20190211788
    Abstract: A high-pressure fuel supply pump comprising a suction valve disposed on a suction side of a pressurizing chamber, an engagement member having a protrusion part that protrudes toward the outer periphery and biasing the suction valve by use of the force of a spring, a stator for generating a magnetic attraction force, and a plunger drawn by the magnetic attraction force and driving the engagement member toward the stator by engaging with the protrusion part, the fuel supply pump being configured so that the area of the fuel passage is smallest between the outer periphery of the protrusion part and the inner periphery of the plunger, and so that a tapered section whereby the area of the flow path increases from the portion where the area of the passage is smallest toward the pressurizing chamber or toward the suction valve side is formed.
    Type: Application
    Filed: August 2, 2017
    Publication date: July 11, 2019
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Yuitsu KODAMA, Yukihiro YOSHINARI, Kenichiro TOKUO, Yuuki TAKAHASHI
  • Patent number: 10337480
    Abstract: Provided is a high-pressure fuel pump in which responsiveness of closing a suction valve can be maintained even when the high-pressure fuel pump is increased in pressure or capacity of the high-pressure fuel pump is increased, thereby ensuring discharge efficiency. Therefore, the high-pressure fuel pump includes the rod that urges the suction valve in the valve opening direction, the mover that drives the rod in the valve closing direction, and the solenoid that generates a magnetic attraction force for moving the mover in the valve closing direction. After the suction valve starts moving from the suction valve closing position in the valve opening direction, the rod reaches the suction valve closing position and further moves in the valve opening direction.
    Type: Grant
    Filed: August 1, 2016
    Date of Patent: July 2, 2019
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Kenichiro Tokuo, Ryo Kusakabe, Shunsuke Aritomi, Satoshi Usui, Masayuki Suganami, Minoru Hashida, Masamichi Yagai, Yuta Saso, Atsuji Saito
  • Patent number: 10316808
    Abstract: To reduce collision noise created by the operation of an electromagnetic suction valve provided on a high pressure fuel supply pump, the mass of a member which collides by magnetic attractive force is reduced. The noise generated when a core and an anchor collide with each other by magnetic attractive force depends on the magnitude of the kinetic energy of a moving element. The kinetic energy to be consumed in the collision is only the kinetic energy of the anchor. The kinetic energy of a rod, being absorbed by a spring, does not contribute to the noise; thus, the energy when the anchor and the core collide with each other can be reduced, whereby the noise to be created can be reduced.
    Type: Grant
    Filed: February 9, 2018
    Date of Patent: June 11, 2019
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Tatsuo Kawano, Kenichiro Tokuo, Satoshi Usui, Hiroyuki Yamada, Katsumi Miyazaki
  • Patent number: 10253741
    Abstract: An object is to suppress cavitation generated at a distal end portion of a seat face when a valve body and a seat portion collide with each other. In a relief valve of a fuel pump, an intersection between the seat face and a flow channel hole is formed at a position more distant than the seat portion formed of the valve body in a valve closing state and the seat face in order to suppress generation of cavitation bubbles when the valve body improves and releases high-pressure fuel.
    Type: Grant
    Filed: April 15, 2016
    Date of Patent: April 9, 2019
    Assignee: Hitachi Automotive Systems, Ltd
    Inventors: Moritsugu Akiyama, Shigehiko Omata, Katsutoshi Kobayashi, Kenichiro Tokuo
  • Patent number: 10247181
    Abstract: A high-pressure fuel pump includes a pressurizing chamber for pressurizing fuel, an outlet valve for discharging the fuel pressurized in the pressurizing chamber to an outlet passage, a relief passage for connecting the outlet passage located downstream of the outlet valve and the pressurizing chamber with each other while bypassing the outlet valve. A relief valve device is provided in the relief passage and adapted to open when an internal pressure of the outlet passage becomes higher than that of the pressurizing chamber, thereby providing communication between the outlet passage and the pressurizing chamber. The relief valve includes a relief spring mechanism for pressing a relief valve to a relief valve seat. At least the relief spring mechanism among members of the relief valve device is provided outside the pressurizing chamber in the pump body.
    Type: Grant
    Filed: February 11, 2016
    Date of Patent: April 2, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Satoshi Usui, Hiroyuki Yamada, Kenichiro Tokuo, Toru Onose, Masami Abe
  • Publication number: 20190017482
    Abstract: A high-pressure fuel supply pump includes a pressurizing chamber, a piston plunger, and an electromagnetically-driven intake valve mechanism. The piston plunger reciprocates within the pressurizing chamber. The electromagnetically-driven intake valve mechanism is provided at an inlet of the pressurizing chamber. The electromagnetically-driven intake valve mechanism includes an anchor which pulls a plunger rod, a fixed core which attracts the anchor, and a yoke in which inner peripheral part has the fixed core and the anchor. The fixed core is fixed to a bottom part of the yoke. A through hole is formed at a bottom part of the fixed core.
    Type: Application
    Filed: August 13, 2018
    Publication date: January 17, 2019
    Inventors: Satoshi USUI, Kenichiro TOKUO, Tatsuo KAWANO, Masahiko HAYATANI, Shingo TAMURA, Hiroyuki YAMADA, Katsumi MIYAZAKI
  • Publication number: 20180238287
    Abstract: Provided is a high-pressure fuel pump in which responsiveness of closing a suction valve can be maintained even when the high-pressure fuel pump is increased in pressure or capacity of the high-pressure fuel pump is increased, thereby ensuring discharge efficiency. Therefore, the high-pressure fuel pump includes the rod that urges the suction valve in the valve opening direction, the mover that drives the rod in the valve closing direction, and the solenoid that generates a magnetic attraction force for moving the mover in the valve closing direction. After the suction valve starts moving from the suction valve closing position in the valve opening direction, the rod reaches the suction valve closing position and further moves in the valve opening direction.
    Type: Application
    Filed: August 1, 2016
    Publication date: August 23, 2018
    Inventors: Kenichiro TOKUO, Ryo KUSAKABE, Shunsuke ARITOMI, Satoshi USUI, Masayuki SUGANAMI, Minoru HASHIDA, Masamichi YAGAI, Yuta SASO, Atsuji SAITO