Fuel injector

A fuel injector configured and arranged to inject fuel into a combustion chamber of an engine comprising:

• a casing member including a hydraulic chamber configured to contain pressurized fuel at a prescribed pressure and a flow rate regulating hole arranged to discharge the fuel from inside the hydraulic chamber;
• a fuel discharge valve configured and arranged to open and close the flow rate regulating hole of the casing member;
• a micro nozzle disposed in a downstream part with respect to the fuel discharge valve, the micro nozzle having at least one through hole arranged to inject the fuel discharged from the flow rate regulating hole into the combustion chamber, the micro nozzle further including a heating structure configured and arranged to selectively emit heat to raise temperature of the fuel that passes through the at least one through hole of the micro nozzle upon activation of the heating structure;
• and
• an energy supply unit operatively coupled to the micro nozzle to selectively supply electric power to the micro nozzle so that the heating structure of the micro nozzle emits heat when supplied with the electric power.

A fuel injector configured and arranged to inject fuel into a combustion chamber of an engine comprising:

• a casing member including a hydraulic chamber configured to contain pressurized fuel at a prescribed pressure and a flow rate regulating hole arranged to discharge the fuel from inside the hydraulic chamber;
• a fuel discharge valve configured and arranged to open and close the flow rate regulating hole of the casing member;
• a micro nozzle disposed in a downstream part with respect to the fuel discharge valve, the micro nozzle having at least one through hole arranged to inject the fuel discharged from the flow rate regulating hole into the combustion chamber, the micro nozzle including
• a heating structure configured and arranged to selectively emit heat to raise temperature of the fuel that passes through the at least one through hole of the micro nozzle upon activation of the heating structure, the heating structure configured and arranged such that an electric current flows between a first main surface and a second main surface of the micro nozzle, the heating structure comprising an electrically conductive substrate having first and second main surfaces, the electrically conductive substrate including a through hole forming section in which the at least one through hole is formed and a substrate perimeter section that is arranged around an outside perimeter of the through hole forming section,
• a thermal insulation member arranged around a perimeter portion of the at least one through hole in the through hole forming section of the electrically conductive substrate,
• a first impurity layer disposed on one of the first and second main surfaces of the electrically conductive substrate in the substrate perimeter section thereof,
• a pair of second impurity layers disposed on the first and second main surfaces of the electrically conducting substrate, respectively, in the through hole forming section and the substrate perimeter section over the first impurity layer formed on the one of the first and second main surfaces of the electrically conducting substrate in the substrate perimeter section, the second impurity layers having an opposite conductivity type from the first impurity layer, and
• first and second lead electrodes provided on the second impurity layers on the first and second main surfaces of the electrically conducting substrate in the substrate perimeter section so that electric current flows from the second impurity layer to the electrically conductive substrate in the through hole forming section to raise the temperature of the fuel that passes through the at least one through hole when electric power is applied to the first and second lead electrodes;
• and
• an energy supply unit operatively coupled to the micro nozzle to selectively supply the electric power to the first and second lead electrodes of the micro nozzle so that the heating structure of the micro nozzle emits heat when supplied with the electric power.

A fuel injector configured and arranged to inject fuel into a combustion chamber of an engine comprising:

• a casing member including a hydraulic chamber configured to contain pressurized fuel at a prescribed pressure and a flow rate regulating hole arranged to discharge the fuel from inside the hydraulic chamber;
• a fuel discharge valve configured and arranged to open and close the flow rate regulating hole of the casing member;
• and
• a micro nozzle disposed in a downstream part with respect to the fuel discharge valve, the micro nozzle having at least one through hole arranged to inject the fuel discharged from the flow rate regulating hole into the combustion chamber, the micro nozzle further including
• a heating structure configured and arranged to selectively emit heat to raise temperature of the fuel that passes through the at least one through hole of the micro nozzle upon activation of the heating structure, the heating structure of the micro nozzle including an electrically conductive member with the through hole provided therein, and
• a thermal insulating entity arranged around a perimeter portion of the at least one through hole in the electrically conductive member.