Abstract: In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the engine includes a lower cavity, an upper cavity, and a lip portion between the lower cavity and the upper cavity. A controller causes a main injection and at least one pilot injection to be executed when an engine operates in a first state and a second state in which the speed is higher than the speed in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller maintains an injection amount of the main injection and increases an injection amount of the pilot injection(s) when the engine operates in the second state as compared to when the engine operates in the first state.

Abstract: In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the compression-ignition engine includes a lower cavity, an upper cavity, and a lip portion between the lower cavity and the upper cavity. A controller causes a main injection and at least one pilot injection to be executed when the engine operates in a first state and a second state in which the speed is higher than the speed in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller increases an injection amount per pilot injection when the engine operates in the second state than when the engine operates in the first state.

Abstract: A diesel engine system is provided, which includes a piston having a cavity dented downwardly in a crown surface thereof and having a bottom part, a peripheral part dented so as to be convex radially outward, and a lip part formed above the peripheral part and protruding so as to be convex radially inward in a cross-sectional view. An injection controller causes an injector to perform, during operation in a given operating range, a main injection in which injected fuel is directed to the lip part, and an after-injection in which a smaller amount of the fuel than the main injection is injected at a given timing later than the main injection in an expansion stroke. An injection interval period from an end of the main injection to a start of the after-injection is shorter as a temperature parameter related to a progress of a warmup of engine increases.

Abstract: A diesel engine system has a piston in which a cavity is formed in a crown surface. The cavity has a bottom part, a peripheral part dented so as to be convex radially outward in a cross-sectional view, and a lip part formed above the peripheral part and protruding so as to be convex radially inward in the cross-sectional view. An injection controller causes an injector to perform, during operation in a given operating range, a main injection in which injected fuel is directed to the lip part, and an after-injection in which a smaller amount of fuel than the main injection is injected at a given period later than the main injection in an expansion stroke. An injection interval period that is a period of time from an end of the main injection to a start of the after-injection is shorter as an injection pressure of fuel increases.

Abstract: In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the compression-ignition engine includes a lower cavity, an upper cavity, and a lip portion between the lower cavity and the upper cavity. A controller causes a main injection and at least one pilot injection to be executed when the engine operates in a first state and a second state in which the load is higher than the load in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller causes a ratio of injection amount per pilot injection to the total injection amount to be higher when the engine operates in the second state than when the engine operates in the first state.

Abstract: A diesel engine system is provided, which includes a piston having a cavity dented downwardly in a crown surface thereof and having a bottom part, a peripheral part dented so as to be convex radially outward, and a lip part formed above the peripheral part and protruding so as to be convex radially inward in a cross-sectional view. An injection controller causes an injector to perform, during operation in a given operating range, a main injection in which injected fuel is directed to the lip part, and an after-injection in which a smaller amount of the fuel than the main injection is injected at a given timing later than the main injection in an expansion stroke. An injection interval period from an end of the main injection to a start of the after-injection is shorter as a temperature parameter related to a progress of a warmup of engine increases.

Abstract: A diesel engine system has a piston in which a cavity is formed in a crown surface. The cavity has a bottom part, a peripheral part dented so as to be convex radially outward in a cross-sectional view, and a lip part formed above the peripheral part and protruding so as to be convex radially inward in the cross-sectional view. An injection controller causes an injector to perform, during operation in a given operating range, a main injection in which injected fuel is directed to the lip part, and an after-injection in which a smaller amount of fuel than the main injection is injected at a given period later than the main injection in an expansion stroke. An injection interval period that is a period of time from an end of the main injection to a start of the after-injection is shorter as an injection pressure of fuel increases.

Abstract: A fuel injection control system for a diesel engine is configured to, during one combustion cycle, perform multiple fuel injections to induce multiple combustions in a cylinder. The fuel injection control system comprises a PCM for controlling a fuel injection of the diesel engine. The PCM is configured to execute control for: at a first timing during compression stroke, injecting fuel in a first amount; at a second timing after the first timing and during the compression stroke, injecting fuel in a second amount greater than the first amount; and, at a third timing after the second timing and approximately a top dead center of the compression stroke, injecting fuel in a maximum amount greater than the first and second amounts.

Abstract: A fuel injection control system for a diesel engine configured to perform multiple fuel injections to induce multiple combustions. A PCM is configured to, during compression stroke, perform a main injection and multiple pre-stage injections prior to the main injection, and to cause a ratio of a maximum injection amount of the multiple pre-stage injections to an injection amount of the main injection to become smaller when the load of the diesel engine is less than a given load than when the load of the diesel engine is greater than the given load, and cause an injection interval between the main injection and one of the multiple pre-stage injections immediately preceding the main injection to become smaller when the load of the diesel engine is less than the given load than when the load of the diesel engine is greater than the given load.

Abstract: A fuel injection control device causes an injector to execute main injection or pilot injection toward a joint portion, and low penetration injection to inject fuel at timing earlier than the pilot injection in a PILOT region or at timing later than the main injection in an AFTER region. The fuel injection control device causes the low penetration injection to be executed to inject the fuel only in a radial central region of a combustion chamber.

Abstract: In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the engine includes a lower cavity, an upper cavity, and a lip portion therebetween. A controller causes a main injection and at least one pilot injection to be executed when the engine operates in a first state and a second state in which the load is lower than the load in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller sets the timing of the pilot injection(s) so that the distribution ratio of the fuel spray of the pilot injection(s) for the lower cavity is higher when the engine operates in the first state than when in the second state.

Abstract: A fuel injection control causes a fuel injection valve to execute at least: a main injection to inject fuel at timing when a piston is positioned near a compression top dead center; a pilot injection to inject the fuel at timing earlier than the main injection; and a low penetration injection to inject the fuel at timing earlier than the pilot injection or timing later than the main injection. The fuel injection control device includes: a first injection control module that executes at least one of the main injection or the pilot injection at timing to inject the fuel toward a joint portion of a cavity; and a second injection control module that executes the low penetration injection to inject the fuel only into a radial central region of a combustion chamber.

Abstract: In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the engine includes a lower cavity, an upper cavity, and a lip portion between the lower cavity and the upper cavity. A controller causes a main injection and at least one pilot injection to be executed when the engine operates in a first state and a second state in which the load is lower than the load in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller outputs a control signal to a fuel injection valve so that a distribution ratio for the upper cavity is higher when the engine operates in the second state than when in the first state.

Abstract: In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the compression-ignition engine includes a lower cavity, an upper cavity, and a lip portion between the lower cavity and the upper cavity. A controller causes a main injection and at least one pilot injection to be executed when the engine operates in a first state and a second state in which the load is higher than the load in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller causes a ratio of injection amount per pilot injection to the total injection amount to be higher when the engine operates in the second state than when the engine operates in the first state.

Abstract: In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the compression-ignition engine includes a lower cavity, an upper cavity, and a lip portion between the lower cavity and the upper cavity. A controller causes a main injection and at least one pilot injection to be executed when the engine operates in a first state and a second state in which the speed is higher than the speed in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller increases an injection amount per pilot injection when the engine operates in the second state than when the engine operates in the first state.

Abstract: In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the engine includes a lower cavity, an upper cavity, and a lip portion between the lower cavity and the upper cavity. A controller causes a main injection and at least one pilot injection to be executed when the engine operates in a first state and a second state in which the load is lower than the load in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller outputs a control signal to a fuel injection valve so that a distribution ratio for the upper cavity is higher when the engine operates in the second state than when in the first state.

Abstract: In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the engine includes a lower cavity, an upper cavity, and a lip portion between the lower cavity and the upper cavity. A controller causes a main injection and at least one pilot injection to be executed when an engine operates in a first state and a second state in which the speed is higher than the speed in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller maintains an injection amount of the main injection and increases an injection amount of the pilot injection(s) when the engine operates in the second state as compared to when the engine operates in the first state.

Abstract: In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the engine includes a lower cavity, an upper cavity, and a lip portion therebetween. A controller causes a main injection and at least one pilot injection to be executed when the engine operates in a first state and a second state in which the load is lower than the load in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller sets the timing of the pilot injection(s) so that the distribution ratio of the fuel spray of the pilot injection(s) for the lower cavity is higher when the engine operates in the first state than when in the second state.

Abstract: Provided is an engine control device capable of, when performing control of an in-cylinder oxygen concentration according to engine operation state, controlling an engine to accurately realize vehicle behavior intended by a driver, while suppressing generation of knock noises due to abnormal combustion.

Abstract: A fuel injection control system for a diesel engine is configured to, during one combustion cycle, perform multiple fuel injections to induce multiple combustions in a cylinder. A PCM controls fuel injection of the diesel engine. The PCM is configured to execute control for: at a first timing during compression stroke, starting a first fuel injection; a second timing during the compression stroke at which a time period corresponding to a first crank angle period has elapsed after a completion of the first fuel injection, starting a second fuel injection; and, at a third timing approximately a top dead center of the compression stroke at which a time period corresponding to a second crank angle period has elapsed after a completion of the second fuel injection, starting a third fuel injection. The second crank angle period is less than the first crank angle period.