A piston has a piston crown portion forming at least one arcuate indent in aligned fashion with a fuel jet discharged into a combustion chamber. Each arcuate event forms lobes, which separate the fuel jet into portions, or is tiered, to accommodate fuel jet portions being discharged into the combustion chamber at different times. Each lobe or tier includes an entry surface, a recirculation surface and a wall to separate it from adjacent lobes or tiers, respectively.

A fuel injection apparatus includes: an injector disposed at a position offset from an ignition plug toward an intake port and injecting a fuel spray toward a crown surface of a piston, and an injection controller causing the injector to perform injection in accordance with an amount and timing of fuel injection preset in accordance with an operating state of an engine. The piston includes: a first recess formed by recessing a central portion of the crown surface and a second recess formed by recessing part of the first recess on an injector side further than the first recess. The injector injects 50% or more of fuel to be injected for the last fuel injection toward the second recess during a compression stroke, and injects part of the fuel to be injected for the last fuel injection toward an area of the first recess other than the second recess.

A piston is used for an engine including: an ignition plug disposed in the vicinity of a central axis of a cylinder; intake and exhaust ports disposed at positions where the ignition plug is interposed therebetween; and an injector disposed at a position offset from the ignition plug toward the intake port to inject fuel sprays toward a crown surface of the piston. The piston includes: a recess formed by recessing the crown surface of the piston with respect to other portions of the crown surface, in which the recess includes a step on an outer peripheral edge over the entire circumference thereof with respect to the other portions, and a pair of lateral sides formed straightly so as to extend substantially in parallel to a straight line connecting the injector and the ignition plug when seen in a direction of the cylinder axis.

An engine has an engine body, an injector, and a control section which controls a fuel injection amount and an injection state of the injector. The control section predicts a state of temperature in the combustion chamber, and controls the injector such that a volume of an air-fuel mixture layer formed in the combustion chamber is larger when the predicted temperature is high, than when the predicted temperature is low, even when same fuel amounts are injected.

Systems and methods are provided for operation of fuel injectors within an applied-ignition, direct-injection internal combustion engine. In one example, a needle of a fuel injector is moved from a retracted position to an extended position relative to a plurality of injection holes of a nozzle of the fuel injector, with at least one injection hole being separated from a fuel supply system earlier than each other injection hole. In a partially retracted position, fuel flow along a first side of the needle is decreased relative to fuel flow along a second side of the needle.

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 piston is used for an engine including: an ignition plug disposed in the vicinity of a central axis of a cylinder; intake and exhaust ports disposed at positions where the ignition plug is interposed therebetween; and an injector disposed at a position offset from the ignition plug toward the intake port to inject fuel sprays toward a crown surface of the piston. The piston includes: a recess formed by recessing the crown surface of the piston with respect to other portions of the crown surface, in which the recess includes a step on an outer peripheral edge over the entire circumference thereof with respect to the other portions, and a pair of lateral sides formed straightly so as to extend substantially in parallel to a straight line connecting the injector and the ignition plug when seen in a direction of the cylinder axis.

A fuel injection apparatus includes: an injector disposed at a position offset from an ignition plug toward an intake port and injecting a fuel spray toward a crown surface of a piston, and an injection controller causing the injector to perform injection in accordance with an amount and timing of fuel injection preset in accordance with an operating state of an engine. The piston includes: a first recess formed by recessing a central portion of the crown surface and a second recess formed by recessing part of the first recess on an injector side further than the first recess. The injector injects 50% or more of fuel to be injected for the last fuel injection toward the second recess during a compression stroke, and injects part of the fuel to be injected for the last fuel injection toward an area of the first recess other than the second recess.

A control device of a gasoline direct-injection engine is provided. The control device includes an engine body, an injector, and a controller. Within a high load operating range, the controller causes the injector to perform a pre-injection and a post injection. In the pre-injection, the fuel is injected to cause a fuel concentration within an in-cylinder radially peripheral section to be higher than a fuel concentration within an in-cylinder radially central section at a timing for the fuel to ignite. In the post injection, the fuel is injected to cause the fuel concentration within the radially central section to be higher than the fuel concentration within the radially peripheral section at a timing for the fuel to ignite. The timing for the fuel injected in the post injection to ignite is after an oxidative reaction of the fuel injected in the pre-injection occurs and after a compression top dead center.

In one embodiment, a combustion system for an engine is disclosed. The system includes a cylinder block that defines a cylinder bore and opposing pre-chambers located along a circumference of the cylinder bore. The system also includes a fuel injector located equidistant from the circumference of the cylinder bore that injects fuel in a direction perpendicular to a diameter of the cylinder bore. The system further includes a piston located within the cylinder bore that has a substantially conically shaped crown having fuel direction grooves that direct the fuel from the fuel injector towards the opposing pre-chambers.