The invention relates to a control device applied to a cylinder injection type of an internal combustion engine (10). The control device control a disperse parameter for changing a degree of a spread of the fuel spray injected from the injector (20) such that the maximum degree of the spread of the fuel spray under a state where an amount of the fuel adhering to the spark generation part (31a) of the spark plug (30) at the ignition timing corresponds to a first amount, is smaller than the maximum degree of the spread of the fuel spray under a state where the amount of the fuel adhering to the spark generation part at the ignition timing corresponds to a second amount smaller than said first amount.

A spark-ignition direct fuel injection valve includes, at least, a seat member provided with a fuel injection hole and a valve seat and a valve body which controls fuel injection from the injection hole by contacting and separating from the valve seat. In the spark-ignition direct fuel injection valve: the injection hole has an injection hole inlet which is open inwardly of the seat member and an injection hole outlet which is open outwardly of the seat member; an opening edge of the injection hole inlet has a first round-chamfered portion formed on an upstream side with respect to a fuel flow toward the injection hole inlet; and an extending length (L) of the injection hole does not exceed three times a hole diameter (D) of the injection hole.

Disclosed herein is a vehicular high pressure direct injection type injector with valve seat body for fuel-atomization. A nozzle hole has an elliptical cross-section so that the fuel injection speed can be increased, whereby a fuel atomization effect can be maximized. Furthermore, a stepped hole is formed under the nozzle hole so that the nozzle hole can be fundamentally prevented from becoming clogged with combustion byproducts.

A Laval shape is formed between the nozzle seat surface and needle tip portion. An injection hole also has the Laval shape. When the needle lift amount is small, a fuel flow velocity reaches an acoustic velocity in valve-opening portion. The fuel flow velocity further accelerated to a supersonic velocity at the Laval shape. When the needle lift amount is large, the fuel flows into the injection hole without a velocity decrease. Thus, the fuel flow velocity reaches the supersonic velocity at the Laval shape.

In a fuel injection valve, it is possible to obtain spray in which the penetrating force of injected fuel is suppressed. The fuel injection valve includes a valve seat that forms a gap with a valve body, the gap allowing fuel to pass therethrough, and multiple injection holes that are located further downstream from the gap. The fuel to which pressure is applied flows out from the injection holes. When the flow velocity of the fuel in the gap formed between the valve body and the valve seat is indicated by meters per second, the flow velocity is set to be greater than a value obtained by multiplying the square root of the pressure applied to the fuel by 28. In this manner, the flow velocity in the gap increases, and flow velocity distribution inside the injection hole is uniformized, thereby suppressing an increase in penetration.

A ducted combustion system is disclosed. The ducted combustion system includes a combustion chamber bound by a flame deck surface of a cylinder head of an internal combustion engine and by a piston top surface of a piston disposed within the internal combustion engine. The system includes a fuel injector including one or more orifices, the one or more orifices injecting fuel into the combustion chamber as at least one fuel jet. The system includes at least one duct disposed within the combustion chamber between the flame deck surface and the piston top surface, the at least one duct including one or more structural tabs proximate to an outlet of the at least one duct and being disposed such that the at least one fuel jet, at least partially, enters one of the at least one duct upon being injected into the combustion chamber.

An object of the present invention is to improve the exhaust emission for a fuel injection valve having a stepped injection hole constructed so that a small diameter portion and a large diameter portion are communicated with each other with a stepped portion intervening therebetween. The present invention resides in a fuel injection valve comprising a cylindrical nozzle body which has a tip portion formed to have a conical shape, an injection hole which penetrates from an inner circumferential surface to an outer circumferential surface of the nozzle body, the injection hole being constructed so that a small diameter portion, which is positioned on a side of the inner circumferential surface of the nozzle body, is communicated with a large diameter portion which is positioned on a side of the outer circumferential surface of the nozzle body, with a stepped portion intervening therebetween, and a valve plug which is accommodated slidably in the nozzle body and which opens/closes the injection hole, wherein a ratio of the hole diameter of the large diameter portion with respect to the hole diameter of the small diameter portion is not less than 3.1 and not more than 4.0, a ratio of a length of the large diameter portion with respect to a length of the small diameter portion is not less than 0.25 and not more than 0.55, and a ratio of the length of the large diameter portion with respect to the hole diameter of the large diameter portion is not less than 0.4 and not more than 1.6.

A first injection hole included by an injection nozzle is formed such that an angle that a first virtual line passing a first inner-wall-side center point away from a center axis by a predetermined first distance, forms with the center axis becomes a first injection angle, and an angle that first injection hole inner walls form becomes a first open angle. A second injection hole included by the injection nozzle is formed such that an angle that a second virtual line passing a second inner-wall-side center point away from the center axis by a predetermined second distance, forms with the center axis becomes a second injection angle that is smaller than the first injection angle, and an angle that second injection hole inner walls form becomes a second open angle that is larger than the first open angle.

A fuel injector configured as a high-pressure injection valve for the direct injection of fuel into a combustion chamber includes: a housing having an housing end face on the combustion chamber side; an actuator; a valve-closure member operable by the actuator; at least one outlet orifice in the housing end face on the combustion chamber side for the fuel, the valve-closure member selectively closing or opening the outlet orifice; and a ring provided round about the outlet orifice in the housing end face on the combustion chamber side.

In a fuel injection valve used in an internal combustion engine, fuel spray travel distance is shortened. There is provided a fuel injection valve including a seat member, in which the seat member includes a conical seat surface that seats fuel by coming in contact with a valve body, and inlet opening portions of a plurality of fuel injection holes on the conical seat surface, and is configured such that an axis of the injection hole connecting the centers of an inlet and an outlet of the fuel injection hole is along a plurality of different conical surfaces, and in which, in an outlet section that is configured of a plane parallel to an inlet section of the inlet opening portion of the fuel injection hole and is positioned at the outlet of the fuel injection hole, the seat member includes the injection hole in which a major axis direction of an ellipse of the outlet section has an inclination angle of greater than 0 degrees with respect to a straight line in a fuel injection direction, which is obtained by projecting the axis of the injection hole on the outlet section, and an inclination angle of a degree before being perpendicular to the straight line in the fuel injection direction.