Patents by Inventor Naotaro Nagai

Naotaro Nagai 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: 12366221
    Abstract: An object of the present invention is to provide a fuel injection system capable of suppressing an occurrence of distortion in an injector during assembly of components. A fuel injection system (3) includes: a bracket (5) which is fixed to a cylinder head (21) of an engine (2); a fuel accumulator (6) which is supported by and fixed to the bracket (5) and which accumulates pressure of fuel supplied from a fuel pump; and an injector (7) which is directly connected to the fuel accumulator (6) and mounted to the cylinder head (21) and which injects the fuel, supplied from the fuel accumulator (6), into a combustion chamber. At least one of the fuel accumulator (6) and the bracket (5) has guide members (64, 513) which guide the injector (7) to a mount position on the cylinder head (21).
    Type: Grant
    Filed: February 21, 2022
    Date of Patent: July 22, 2025
    Assignee: KUBOTA CORPORATION
    Inventors: Akira Tamura, Hiroki Oso, Naotaro Nagai, Shingo Matsunobu, Masanari Tennomi
  • Publication number: 20250020088
    Abstract: A diesel engine 1 includes: an injector 15; a control device which controls an injection timing of fuel 81 injected from the injector 15; and exhaust circulating means. The control device controls the injection timing of main injection and pre-injection performed prior to the main injection and executes control such that, by ensuring a premixing period of the pre-injection from start of the pre-injection until ignition of an air-fuel mixture of the fuel 81 injected by the pre-injection and the air AR, a homogenous and lean premixed air-fuel mixture is generated in the auxiliary combustion chamber 13 by the fuel 81 injected by the pre-injection and air AR, and the premixing period of the main injection from the start of the main injection until ignition of the air-fuel mixture of the fuel 81 injected by the main injection and the air AR is ensured.
    Type: Application
    Filed: August 29, 2022
    Publication date: January 16, 2025
    Inventors: Yasushi KOBAYASHI, Naotaro NAGAI, Rina KANEKO, Masanari TENNOMI, Naruhiro MATSUO
  • Publication number: 20240254953
    Abstract: An object of the present invention is to provide a fuel injection system capable of suppressing an occurrence of distortion in an injector during assembly of components. A fuel injection system (3) includes: a bracket (5) which is fixed to a cylinder head (21) of an engine (2); a fuel accumulator (6) which is supported by and fixed to the bracket (5) and which accumulates pressure of fuel supplied from a fuel pump; and an injector (7) which is directly connected to the fuel accumulator (6) and mounted to the cylinder head (21) and which injects the fuel, supplied from the fuel accumulator (6), into a combustion chamber. At least one of the fuel accumulator (6) and the bracket (5) has guide members (64, 513) which guide the injector (7) to a mount position on the cylinder head (21).
    Type: Application
    Filed: February 21, 2022
    Publication date: August 1, 2024
    Inventors: Akira TAMURA, Hiroki OSO, Naotaro NAGAI, Shingo MATSUNOBU, Masanari TENNOMI
  • Patent number: 12012909
    Abstract: Provided is an injector control device which is capable of setting a preceding injection amount to a fuel injection amount that is less than a main injection amount, while suppressing situations where preceding injections executed prior to a main injection in multi-stage injection are eliminated. An injector control device 2 includes: an injection amount setting unit 211 that sets, as a total injection amount, a total of fuel injection amounts in multi-stage injection in a single cycle, and sets, as a preceding injection amount, a fuel injection amount in a preceding injection executed prior to a main injection in the multi-stage injection; an energization period setting unit 212 that sets an energization period of an injector 31 based on the fuel injection amounts set by the injection amount setting unit 211; and an injector driving unit 213 that controls driving of the injector 31 based on the energization period set by the energization period setting unit 212.
    Type: Grant
    Filed: February 21, 2022
    Date of Patent: June 18, 2024
    Assignee: KUBOTA CORPORATION
    Inventors: Yasushi Kobayashi, Shingo Matsunobu, Kiichi Suehiro, Naotaro Nagai
  • Publication number: 20240011449
    Abstract: Provided is an injector control device which is capable of setting a preceding injection amount to a fuel injection amount that is less than a main injection amount, while suppressing situations where preceding injections executed prior to a main injection in multi-stage injection are eliminated. An injector control device 2 includes: an injection amount setting unit 211 that sets, as a total injection amount, a total of fuel injection amounts in multi-stage injection in a single cycle, and sets, as a preceding injection amount, a fuel injection amount in a preceding injection executed prior to a main injection in the multi-stage injection; an energization period setting unit 212 that sets an energization period of an injector 31 based on the fuel injection amounts set by the injection amount setting unit 211; and an injector driving unit 213 that controls driving of the injector 31 based on the energization period set by the energization period setting unit 212.
    Type: Application
    Filed: February 21, 2022
    Publication date: January 11, 2024
    Inventors: Yasushi KOBAYASHI, Shingo MATSUNOBU, Kiichi SUEHIRO, Naotaro NAGAI
  • Patent number: 10774704
    Abstract: In an engine head cover, an upper portion of a partition plate 5, which partitions an inside of a head cover 3 into upper and lower portions, forms a blowby gas passage W having an inlet 6 and an outlet 7 communicating with an intake path 9. A PCV valve 14 disposed on the outlet 7 side, a filter 13 disposed on the inlet 6 side, and a labyrinth 15 disposed between the PCV valve 14 and the filter 13 are provided. A recovery hole 23 which causes a flowdown of trapped oil is formed at a portion on a downstream side of the filter 13 in a flow direction of a blowby gas in the blowby gas passage W and on a lower side of the labyrinth 15 and the pressure regulating valve 14.
    Type: Grant
    Filed: December 5, 2017
    Date of Patent: September 15, 2020
    Assignee: KUBOTA Corporation
    Inventors: Hiroaki Isoshima, Kentaro Shiraishi, Naotaro Nagai
  • Publication number: 20180171840
    Abstract: In an engine head cover, an upper portion of a partition plate 5, which partitions an inside of a head cover 3 into upper and lower portions, forms a blowby gas passage W having an inlet 6 and an outlet 7 communicating with an intake path 9. A PCV valve 14 disposed on the outlet 7 side, a filter 13 disposed on the inlet 6 side, and a labyrinth 15 disposed between the PCV valve 14 and the filter 13 are provided. A recovery hole 23 which causes a flowdown of trapped oil is formed at a portion on a downstream side of the filter 13 in a flow direction of a blowby gas in the blowby gas passage W and on a lower side of the labyrinth 15 and the pressure regulating valve 14.
    Type: Application
    Filed: December 5, 2017
    Publication date: June 21, 2018
    Inventors: Hiroaki Isoshima, Kentaro Shiraishi, Naotaro Nagai