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: 11852093
    Abstract: Low noise control of a high-pressure fuel pump is performed by reducing noise generated by an anchor colliding with a fixing core. A control device 800 for a high-pressure fuel pump controls a suction valve that opens and closes an inflow port through which fuel flows to a pressurizing chamber by performing energization to a solenoid 205 in synchronization with a reciprocating motion of a plunger. A current energized to the solenoid 205 includes a peak current for giving a force to start closing a valve to the suction valve in a stationary state and a holding current for performing switching in a range smaller a maximum value of the peak current in order to hold the suction valve in a valve closing state.
    Type: Grant
    Filed: December 25, 2020
    Date of Patent: December 26, 2023
    Assignee: Hitachi Astemo, Ltd.
    Inventors: Toshihiro Aono, Osamu Mukaihara, Kenichiro Tokuo, Hirotaka Nakai, Kotaro Oki, Shunsuke Aritomi, Akiyasu Miyamoto
  • Patent number: 11781513
    Abstract: Provided is a discharge valve mechanism capable of improving responsiveness when a discharge valve is opened, and a high-pressure fuel supply pump including the discharge valve mechanism.
    Type: Grant
    Filed: December 11, 2020
    Date of Patent: October 10, 2023
    Assignee: HITACHI ASTEMO, LTD.
    Inventors: Kenichiro Tokuo, Hiroyuki Yamada, Kiyotaka Ogura, Shingo Tamura, Yuto Ishizuka
  • Patent number: 11713741
    Abstract: Provided is a fuel supply pump capable of improving welding quality while securing a function of a valve body. A fuel supply pump of the present invention includes a regulating member (discharge valve stopper 84) that guides movement of a valve body (discharge valve 82), a main body portion (body 1) provided with a valve chamber (discharge valve chamber 1d) that houses the regulating member, a sealing member (plug 85) that seals the valve chamber, and a welded portion (welded portion 86) that fixes the sealing member to the main body portion. An annular space portion (annular space portion 60) along an outer periphery of the regulating member is formed between the welded portion and the regulating member.
    Type: Grant
    Filed: October 30, 2020
    Date of Patent: August 1, 2023
    Assignee: HITACHI ASTEMO, LTD.
    Inventors: Masamichi Yagai, Kiyotaka Ogura, Shingo Tamura, Yuto Ishizuka, Hiroyuki Yamada, Kenichiro Tokuo, Minoru Hashida
  • Publication number: 20230038318
    Abstract: Low noise control of a high-pressure fuel pump is performed by reducing noise generated by an anchor colliding with a fixing core. A control device 800 for a high-pressure fuel pump controls a suction valve that opens and closes an inflow port through which fuel flows to a pressurizing chamber by performing energization to a solenoid 205 in synchronization with a reciprocating motion of a plunger. A current energized to the solenoid 205 includes a peak current for giving a force to start closing a valve to the suction valve in a stationary state and a holding current for performing switching in a range smaller a maximum value of the peak current in order to hold the suction valve in a valve closing state.
    Type: Application
    Filed: December 25, 2020
    Publication date: February 9, 2023
    Inventors: Toshihiro AONO, Osamu MUKAIHARA, Kenichiro TOKUO, Hirotaka NAKAI, Kotaro OKI, Shunsuke ARITOMI, Akiyasu MIYAMOTO
  • Publication number: 20230029119
    Abstract: Provided is a discharge valve mechanism capable of improving responsiveness when a discharge valve is opened, and a high-pressure fuel supply pump including the discharge valve mechanism. A discharge valve mechanism 500 includes a valve seat portion 51 having a primary-side flow path, a valve body 52 which can be seated on and separated from the valve seat portion 51, and a guide portion 542a which is formed to be slidable on an outer surface of the valve body 52 and guides movement of the valve body 52 in a contacting/separating direction with respect to the valve seat portion 51. The guide portion 542a includes a portion in which a gap from the outer surface of the valve body 52 is set to a predetermined value or less.
    Type: Application
    Filed: December 11, 2020
    Publication date: January 26, 2023
    Applicant: HITACHI ASTEMO, LTD.
    Inventors: Kenichiro TOKUO, Hiroyuki YAMADA, Kiyotaka OGURA, Shingo TAMURA, Yuto ISHIZUKA
  • Patent number: 11542903
    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: Grant
    Filed: November 16, 2017
    Date of Patent: January 3, 2023
    Assignee: HITACHI ASTEMO, LTD.
    Inventors: Tatsuo Kawano, Kenichiro Tokuo, Satoshi Usui, Masamichi Yagai, Kazuaki Tokumaru
  • Publication number: 20220381213
    Abstract: Provided is a fuel supply pump capable of improving welding quality while securing a function of a valve body. A fuel supply pump of the present invention includes a regulating member (discharge valve stopper 84) that guides movement of a valve body (discharge valve 82), a main body portion (body 1) provided with a valve chamber (discharge valve chamber 1d) that houses the regulating member, a sealing member (plug 85) that seals the valve chamber, and a welded portion (welded portion 86) that fixes the sealing member to the main body portion. An annular space portion (annular space portion 60) along an outer periphery of the regulating member is formed between the welded portion and the regulating member.
    Type: Application
    Filed: October 30, 2020
    Publication date: December 1, 2022
    Applicant: HITACHI ASTEMO, LTD.
    Inventors: Masamichi YAGAI, Kiyotaka OGURA, Shingo TAMURA, Yuto ISHIZUKA, Hiroyuki YAMADA, Kenichiro TOKUO, Minoru HASHIDA
  • Publication number: 20210207567
    Abstract: An object of the invention is to provide a fuel supply pump that improves the lubricity of a plunger that reciprocates on the inner circumference of a cylinder in order to suppress sticking of the plunger that may occur with increasing pressure of fuel. A fuel supply pump includes a plunger that reciprocates in an inner peripheral portion of a cylinder, and a pressurizing chamber that is pressurized by the plunger. An annular groove is formed on an outer periphery of the plunger. The annular groove is located closer to the pressurizing chamber than an axial center position of a cylinder sliding region at the bottom dead center position.
    Type: Application
    Filed: December 7, 2018
    Publication date: July 8, 2021
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Shingo TAMURA, Kenichiro TOKUO, Masayuki SUGANAMI, Kazuaki TOKUMARU
  • Patent number: 11002236
    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: Grant
    Filed: October 26, 2017
    Date of Patent: May 11, 2021
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Atsuji Saito, Satoshi Usui, Minoru Hashida, Masayuki Suganami, Hiroyuki Yamada, Kenichiro Tokuo, Masamichi Yagai, Yuta Saso
  • Patent number: 10961961
    Abstract: A control method of a fuel supply pump includes moving an anchor in the closing valve direction by passing a maximum drive current through the solenoid, and thereafter holding the anchor at a closing valve position by passing a holding current for keeping a closing valve state through the solenoid. The holding current is smaller than the maximum drive current. A current value of a first drive current is smaller than a current value of the holding current. A current value of a second drive current overlaps a range of the current value of the holding current. A current value of a third driving current is equal to or more than the current value of the holding current.
    Type: Grant
    Filed: November 7, 2016
    Date of Patent: March 30, 2021
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Masanori Watanabe, Shunsuke Aritomi, Kenichiro Tokuo, Masayuki Suganami
  • Patent number: 10890151
    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: Grant
    Filed: March 26, 2018
    Date of Patent: January 12, 2021
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Kazuaki Tokumaru, Masahiko Hayatani, Satoshi Usui, Atsuji Saito, Kenichiro Tokuo, Masamichi Yagai, Masayuki Suganami
  • Patent number: 10851751
    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: Grant
    Filed: March 26, 2018
    Date of Patent: December 1, 2020
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Kazuaki Tokumaru, Masahiko Hayatani, Satoshi Usui, Atsuji Saito, Kenichiro Tokuo, Masamichi Yagai, Masayuki Suganami
  • 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