A combustion system is applied to an engine. The combustion system includes an injection device that injects a fuel into a combustion chamber, a spark plug that ignites fuel in the combustion chamber, and a control device that controls the injection device and the spark plug. The control device includes a first control unit that executes predetermined first control. In the first control, control is performed such that, a total injection amount corresponding to all the fuel injected by the injection device in one combustion cycle of the engine is injected within a first period corresponding to a period from valve close timing which brings an intake valve into a closed state until a first half of a compression stroke of the engine ends.

Recent exhaust gas regulation requires reduction of an amount and quantity of particulate matter included in an exhaust gas, and a normal maximum fuel pressure may be increased to approximately 35 MP. When the normal maximum fuel pressure is 35 MPa, a fuel injection valve is required to work for example at a pressure up to 45 MPa. In such a condition, a fluid force may exceed a valve opening force depending on a seat diameter, and a needle valve cannot be kept open and closed, when opening thereof is required.

In order to solve the above problems, a fuel injection valve according to the present invention includes a valve seat portion, a valve body which is seated on or separated from the valve seat portion, an injection hole which is formed on a downstream side from the valve seat portion, and a guide portion which is formed on an upstream side from the valve seat portion seating a valve body seat portion of the valve body to guide a guided portion on a downstream side of the valve body, in which the valve seat portion is formed to have a dimension in a crossing direction crossing an axial direction of 0.4 to 0.8 times a dimension of the guide portion in the crossing direction.

Recent exhaust gas regulation requires reduction of an amount and quantity of particulate matter included in an exhaust gas, and a normal maximum fuel pressure may be increased to approximately 35 MP. When the normal maximum fuel pressure is 35 MPa, a fuel injection valve is required to work for example at a pressure up to 45 MPa. In such a condition, a fluid force may exceed a valve opening force depending on a seat diameter, and a needle valve cannot be kept open and closed, when opening thereof is required.

In order to solve the above problems, a fuel injection valve according to the present invention includes a valve seat portion, a valve body which is seated on or separated from the valve seat portion, an injection hole which is formed on a downstream side from the valve seat portion, and a guide portion which is formed on an upstream side from the valve seat portion seating a valve body seat portion of the valve body to guide a guided portion on a downstream side of the valve body, in which the valve seat portion is formed to have a dimension in a crossing direction crossing an axial direction of 0.4 to 0.8 times a dimension of the guide portion in the crossing direction.

A variable orifice fuel injector has an inward opening needle valve and an outward opening needle valve and has means to directly inject two types of fuels independently and collectively. Both needle valves are fully contained in a nozzle body, with a co-axial smaller needle valve at least partially being contained in a larger needle valve. The materials of the needle valves are individually chosen such that it provides good sealings for liquid and gas fuels.

A system of using a flow disc to modify a spray pattern of a fuel injector is a system used to change the spray pattern of injected fuel to increase the air to fuel ratio of an engine. The system includes a flow disc and a fuel injector. The flow disc modifies the spray pattern of the injected fuel by the fuel injector to increase the air contact with the injected fuel. The flow disc includes a disc body and a plurality of spray holes. The disc body is designed to securely fit within the fuel injector. The arrangement of the plurality of spray holes helps modify the spray pattern of the injected fuel. The fuel injector includes an injector body and a spray tip. The injector body controls the flow of the fuel being injected into the engine. The spray tip serves as the outlet of the fuel injector.

A throttle body has a throttle bore with an inlet, an outlet and an air passage. A throttle valve has a valve head received within the throttle bore. A fuel metering valve is mounted on the throttle body and has a valve element and a fuel outlet, the valve element is movable relative to a valve seat to control fuel flow through the fuel outlet. And the nozzle body is carried by the throttle body and has a fuel passage and a feed passage. The fuel passage is arranged to receive fuel that exits the fuel outlet, and is communicated with a fuel chamber through which fluid flows into the throttle bore. The feed passage is communicated with the air passage and with the fuel passage upstream of the fuel chamber. Air in the feed passage is mixed with fuel in the fuel passage upstream of the fuel chamber.

A throttle body has a throttle bore with an inlet, an outlet and an air passage. A throttle valve has a valve head received within the throttle bore. A fuel metering valve is mounted on the throttle body and has a valve element and a fuel outlet, the valve element is movable relative to a valve seat to control fuel flow through the fuel outlet. And the nozzle body is carried by the throttle body and has a fuel passage and a feed passage. The fuel passage is arranged to receive fuel that exits the fuel outlet, and is communicated with a fuel chamber through which fluid flows into the throttle bore. The feed passage is communicated with the air passage and with the fuel passage upstream of the fuel chamber. Air in the feed passage is mixed with fuel in the fuel passage upstream of the fuel chamber.

An injector for injecting a fluid, including a valve seat, on which a sealing area is situated, and a closing element, which is situated on an injector center line and which, on the valve seat, releases and closes at least one through-opening, the at least one through-opening having a main axis at an angle of inclination with respect to the injector center line, the at least one through-opening having an inflow area, and the inflow area having a tapering design.

An injector for injecting a fluid, including a valve seat, on which a sealing area is situated, and a closing element, which is situated on an injector center line and which, on the valve seat, releases and closes at least one through-opening, the at least one through-opening having a main axis at an angle of inclination with respect to the injector center line, the at least one through-opening having an inflow area, and the inflow area having a tapering design.

A first tubular portion forms a part of a fuel flow passage therein. A first joint surface is formed in one end surface of the first tubular portion. A first inner diameter enlarged portion is formed on a side opposite to the first joint surface. A second tubular portion forms a part of the fuel flow passage therein. A second joint surface is formed in one end surface of the second tubular portion and joined to the first joint surface. A second inner diameter enlarged portion is formed on a side opposite to the second joint surface. A welded portion is formed in an annular shape to extend radially inward from the radially outside of the first joint surface and the second joint surface by welding the first tubular portion and the second tubular portion.