Abstract: A control device of an engine is provided. The engine is operated at a high compression ratio, a geometric compression ratio of the engine being 14:1 or higher. The control device includes a fuel injection controller for controlling a fuel injector of the engine to start a fuel injection in a latter half of a compression stroke within an engine operating range where an engine speed is below a predetermined value and an engine load is above a predetermined value, and an ignition controller for controlling an ignition plug of the engine to retard an ignition timing when a timing for the fuel injection controller to start the fuel injection is on a retarding side of a predetermined timing, the ignition timing being retarded based on a retarding amount of the fuel injection start timing from the predetermined timing.

Abstract: A spark-ignition direct injection engine is provided. The engine includes an engine body, a fuel injection valve, a fuel pressure setting mechanism, an ignition plug, and a controller. The controller switches between a compression-ignition mode where the engine body is operated to perform compression-ignition combustion and a spark-ignition mode where the engine body is operated to perform spark-ignition combustion. Immediately after switching from the spark-ignition mode to the compression-ignition mode, the controller operates the engine body in a compression-ignition initial mode where the fuel pressure is set to be 30 MPa or above and the fuel injection valve is controlled to perform the fuel injection in a period from a late stage of the compression stroke to an early stage of the expansion stroke so that the gas mixture self-ignites to combust.

Abstract: A controller of a laser ignition engine configured to perform ignition by using a laser ignition device configured to emit a laser beam condensed by a lens includes: a combustion state related value acquiring portion configured to acquire a combustion state related value related to a combustion state of the engine; and a contamination determining portion configured to compare the combustion state related value acquired by the combustion state related value acquiring portion with a combustion state determining value to determine whether or not the laser ignition device is contaminated, the combustion state determining value being defined based on the combustion state of the engine when the laser ignition device is not contaminated.

Abstract: When a specific condition requiring a rise in exhaust gas temperature is satisfied, a required fuel amount to be injected from an injector (21) is injected in a split manner, such that the fuel injection is divided to: a main injection (X1) to be initiated a given period before a compression top dead center; an auxiliary injection (X2) to be initiated after initiation of auto-ignited combustion of an air-fuel mixture consisting of air and the fuel injected by the main injection (X1) and before an assumed peak timing (Pk?) of a heat release rate (RH) from the combustion based on the main injection (X1); and a post injection (X3) to be initiated after the assumed peak timing (Pk?) and before completion of combustion based on the main injection (X1) and the auxiliary injection (X2). This makes it possible to raise an exhaust gas temperature while sufficiently ensuring auto-ignitability and fuel economy performance.

Abstract: A control method of a spark ignition engine and a spark ignition engine capable of warming up an engine more promptly while promptly activating a catalyst are provided. Implemented is the control of igniting a mixture at an ignition timing that is set on a more lag side than an MBT, which is an ignition timing in which an output torque of the engine becomes maximum until the catalyst is activated after the engine is started. After the catalyst is activated, until the engine is warmed up control of increasing a ratio of burned gas contained in the mixture within the combustion chamber to be more than the ratio of the burned gas in the mixture during a first period, and control of igniting the mixture containing more burned gas than the burned gas in the first period are implemented.

Abstract: An engine body includes a cylinder with a geometrical compression ratio of 15 or higher, and is supplied with fuel containing at least gasoline. When an operating mode of the engine body is in a high load range, a controller (i.e., a PCM 10) drives a fuel injection valve (i.e., an injector) 67 to inject the fuel at a time within a retarded period between a terminal stage of a compression stroke and an initial stage of an expansion stroke in a low speed range. The controller drives the fuel injection valve to inject the fuel in an intake stroke until an intake valve 21 is closed in a high-load high-speed range.

Abstract: A control device compression-ignition type engine that compression-ignites an air-fuel mixture in cylinders by introducing ozone into the cylinders at a predetermined operating range is provided. The control device detects a first ignition timing of an air-fuel mixture when introducing an intake of a first ozone concentration into the cylinders, detects a second ignition timing of the air-fuel mixture when introducing an intake of a second ozone concentration that differs from the first ozone concentration, and determines the fuel ignition ability based on a difference between the detected first ignition timing and the detected second ignition timing.

Abstract: A combustion chamber structure for an engine is provided. The combustion chamber structure includes a piston formed with a downward dented cavity at a central part of an upper surface thereof, and a fuel injector provided above the piston and on an extended line of a central axis of the piston, the fuel injector changing an injection timing of fuel on a compression stroke according to an operating state of the engine. A fuel injection angle of the fuel injector is designed to satisfy conditions in which the fuel is injected into the cavity and in which a fuel spray collision distance defined from a fuel injection position of the fuel injector to a collision position of the fuel with the cavity is longer than a breakup length defined from the fuel injection position of the fuel injector to a position where an initial breakup of the fuel occurs.

Abstract: A combustion chamber structure for an engine is provided. The structure includes a piston formed with a downward dented cavity in a central part of an upper surface thereof, and a cylinder head forming a combustion chamber having a pent-roof shape. The upper surface of the piston has an annular part extending from an outer edge of the cavity to an outer edge of the upper surface, and surrounding the outer edge of the cavity. The annular part is formed with first and second piston upper surface portions. When the piston is at a top dead center, a ratio of a volume of a space formed between the first piston upper surface portion and a bottom surface of the cylinder head with respect to a volume of a space formed between the second piston upper surface portion and the bottom surface becomes below a predetermined value.

Abstract: A control device of an engine is provided. The engine is operated at a high compression ratio, a geometric compression ratio of the engine being 14:1 or higher. The control device includes a fuel injection controller for controlling a fuel injector of the engine to start a fuel injection in a latter half of a compression stroke within an engine operating range where an engine speed is below a predetermined value and an engine load is above a predetermined value, and an ignition controller for controlling an ignition plug of the engine to retard an ignition timing when a timing for the fuel injection controller to start the fuel injection is on a retarding side of a predetermined timing, the ignition timing being retarded based on a retarding amount of the fuel injection start timing from the predetermined timing.

Abstract: A combustion chamber structure for an engine, wherein the structure includes a piston formed with a downward dented cavity at a central part of an upper surface thereof, a fuel injector provided above the piston and in an extension line of a central axis of the piston, and for injecting fuel toward the cavity of the piston, and ignition plugs provided above the cavity and separated from the fuel injector in radial directions of the piston. A radius of the cavity, a depth of the cavity, and each of positions of the ignition plugs are designed so that a distance by which a mixture gas containing the fuel travels from a fuel injection start timing of the fuel injector to an ignition timing of the ignition plug becomes equal to or longer than a length of a path through which the injected fuel reaches each ignition plug via the cavity.

Abstract: Various systems and methods are disclosed for controlling an internal combustion engine system having an internal combustion engine, a fuel injector which directly injects fuel into a combustion chamber of the internal combustion engine, and a supercharger which supercharges air into the combustion chamber. One example method comprises, injecting fuel into the combustion chamber multiple times so that a first part of the fuel is self ignited and a last part of the fuel being injected during the compression stroke or later in a cylinder cycle when a desired torque of said internal combustion engine system is in a first range; and increasing a pressure of air which the supercharger charges into the combustion chamber as amount of fuel injected into the combustion chamber during a cylinder cycle increases when the desired torque is in the first range.

Abstract: A spark-ignition direct injection engine is provided. The engine includes an engine body, a fuel injection valve, a fuel pressure setting mechanism, an ignition plug, and a controller. The controller operates the engine to perform compression-ignition combustion within a first operating range, and controls the ignition plug to operate the engine to perform spark-ignition combustion within a second operating range. Within a specific part of the first range, the controller sets the fuel pressure to 30 MPa or above, and retards the compression ignition to after a compression top dead center by controlling the injection valve to inject fuel into a cylinder in a period from a late stage of compression stroke to an early stage of expansion stroke. Below the specific part, the controller controls the fuel injection valve to inject the fuel into the cylinder in a period from intake stroke to a mid-stage of the compression stroke.

Abstract: A spark-ignition engine is provided. The engine includes an engine body, a fuel injection valve, an ignition plug, an EGR introduction system, and a controller for operating the engine body by controlling the fuel injection valve, the ignition plug, and the EGR introduction system. The controller controls to combust mixture gas by compressing to self-ignite within a compression self-ignition combustion applying range, and to combust the mixture gas by a spark-ignition using the ignition plug within a spark-ignition combustion applying range. Substantially throughout the spark-ignition combustion applying range, the controller controls the EGR introduction system to introduce cooled EGR gas, and within the compression self-ignition applying range, the controller controls the EGR introduction system to introduce hot EGR gas. The controller controls the EGR introduction system to introduce the hot EGR gas and the cooled EGR gas within a low engine load part of the spark-ignition combustion applying range.

Abstract: A spark-ignition direct injection engine is provided. The engine includes an engine body, a fuel injection valve, a fuel pressure setting mechanism, an ignition plug, and a controller. Within a low engine speed operating range of a predetermined high engine load range, the fuel pressure setting mechanism sets a fuel pressure to 30 MPa or above, the fuel injection valve injects fuel between late stage of compression stroke and early stage of expansion stroke, and the ignition plug performs spark-ignition after the fuel injection completes. Within a high engine speed operating range of the high engine load range, the fuel injection valve injects fuel between intake stroke to mid-stage of compression stroke, and the ignition plug performs the spark-ignition. The ignition timing is changed according to an octane number, the changing width of the ignition timing is shorter within the low engine speed range than the high engine speed range.

Abstract: A controller injects fuel into a cylinder at a high fuel pressure of 30 MPa or higher, at least in a period between a terminal stage of a compression stroke and an initial stage of an expansion stroke when an operating mode of an engine body is at least in a first specified sub-range of a low load range, and at least in a second specified sub-range of a high load range. The controller sets an EGR ratio in the first specified sub-range to be higher than an EGR ratio in the second specified sub-range, and advances start of fuel injection in the first specified sub-range to start of fuel injection in the second specified sub-range.

Abstract: Disclosed is an engine control system which is designed to allow homogeneous-charge compression ignition combustion to be performed in an HCCI region (R) defined as an engine operating region including at least a partial-load range of an engine. In a low load zone (R1) of the HCCI region (R), a lift amount of an intake valve (11) is set to a first predetermined value, and an exhaust valve (12) is allowed to start being opened during an intake stroke at a given timing later than an opening timing of the intake valve (11). Further, in the medium load zone of the HCCI region, the lift amount of the intake valve (11) is gradually increased up to a second predetermined value greater than the first predetermined value, along with an increase in an engine load. The engine control system is capable of adequately controlling an amount of burned gas to be introduced into a cylinder, depending on the engine load to allow the HCCI combustion to be adequately performed in a wider engine load range.

Abstract: An engine body includes a cylinder with a geometrical compression ratio of 15 or higher, and is supplied with fuel containing at least gasoline. When an operating mode of the engine body is in a high load range, a controller (i.e., a PCM 10) drives a fuel injection valve (i.e., an injector) 67 to inject the fuel at a time within a retarded period between a terminal stage of a compression stroke and an initial stage of an expansion stroke in a low speed range. The controller drives the fuel injection valve to inject the fuel in an intake stroke until an intake valve 21 is closed in a high-load high-speed range.

Abstract: A control device of a spark-ignition gasoline engine is provided. The control device includes a controller for operating the engine body by controlling at least a fuel injection valve, an ignition plug, and a fuel pressure variable mechanism. Depending on the engine load range, the controller sets the combustion mode to a compression-ignition mode or a spark-ignition mode. In each mode, the controller also controls the fuel pressure, and the timing of fuel injection and ignition. The controller may also performs external EGR control in each mode.

Abstract: An engine is designed to allow a compression self-ignition combustion under an air-fuel ratio leaner than a stoichiometric air-fuel ratio to be performed at least in a partial-load range of the engine. Under a condition that an engine speed varies at a same load in an engine operating region of the compression self-ignition combustion, a compression end temperature Tx, which is an in-cylinder temperature just before an air-fuel mixture self-ignites, is controlled to be raised higher in a higher engine speed side than in a lower engine speed side. As one example of control for the compression end temperature Tx, an internal EGR amount is controlled to be increased larger in the higher engine speed side than in the lower engine speed side, to raise a compression initial temperature T0 which is an in-cylinder temperature at a start timing of a compression stroke.