An air boost system for a two-cycle engine, such as an EMD engine, which operates with one or more roots blowers, or for similar engines that use gear-driven roots blowers or centrifugal blowers. At least one of the roots blowers is equipped with a variable transmission, which allows airflow into the engine to be varied in accordance with load or other engine operating conditions.

An air boost system for a two-cycle engine, such as an EMD engine, which operates with one or more roots blowers, or for similar engines that use gear-driven roots blowers or centrifugal blowers. At least one of the roots blowers is equipped with a variable transmission, which allows airflow into the engine to be varied in accordance with load or other engine operating conditions.

A compression ignition engine includes: a naphtha injector for supplying naphtha to a combustion chamber; a diesel fuel injector for supplying diesel fuel having a higher boiling point than naphtha; an ignition device for assisting ignition of an air-fuel mixture; and a PCM connected to the naphtha injector, the diesel fuel injector, and the ignition device. When the diesel engine is cold, the PCM supplies only naphtha out of naphtha and diesel fuel, and assists ignition of an air-fuel mixture formed by naphtha.

An engine system may include an engine including a plurality of combustion chambers generating driving torque by combustion of fuel, an intake line through which outside air supplied to the combustion chamber flows, an exhaust line for exhausting the exhaust gas from the combustion chamber to the outside, a turbocharger including a compressor mounted in the intake line and a turbine mounted in the exhaust line, an air supply passage through which a portion of the outside air branched from the intake line and supplied to the combustion chamber, an air supply nozzle connected to the air supply passage and supplying the part of the outside air to the combustion chamber, an air supply pump provided in the air supply passage and providing an injection pressure to the part of the outside air injected into the combustion chamber, and a controller for controlling the air supply nozzle and the air supply pump.

An exhaust purification system including a NOx catalyst 32 provided in an exhaust passage of an internal combustion engine 10 and purifying NOx in exhaust; a MAF sensor 40 for acquiring an air flow-rate of the internal-combustion engine 10; a control unit 60, 70 that execute catalyst regeneration treatment of recovering a NOx purification ability of the NOx catalyst 32 by performing, in combination, air-based control of reducing air flow-rate of the internal-combustion engine 10 to a predetermined target air flow-rate and injection-based control of increasing a fuel injection amount, wherein, in a case of executing the catalyst regeneration treatment, the control unit 60, 70 starts with the air-based control and starts the injection-based control when the air flow-rate acquired by the MAF sensor 40 is reduced to the target air flow-rate.

An exhaust purification system including a NOx catalyst 32 provided in an exhaust passage of an internal combustion engine 10 and purifying NOx in exhaust; a MAF sensor 40 for acquiring an air flow-rate of the internal-combustion engine 10; a control unit 60, 70 that execute catalyst regeneration treatment of recovering a NOx purification ability of the NOx catalyst 32 by performing, in combination, air-based control of reducing air flow-rate of the internal-combustion engine 10 to a predetermined target air flow-rate and injection-based control of increasing a fuel injection amount, wherein, in a case of executing the catalyst regeneration treatment, the control unit 60, 70 starts with the air-based control and starts the injection-based control when the air flow-rate acquired by the MAF sensor 40 is reduced to the target air flow-rate.

In a method for controlling an engine, based on a control map of an engine speed N and a fuel injection amount Q of a common-rail fuel injection unit, a controller calculating the fuel injection amount Q depending on the engine speed N, calculating an injection amount deviation Qn as a fuel injection amount increase, and determining that an engine is in a transient state if the injection amount deviation Qn exceeds a reference transient injection amount deviation A2 or if a transient injection amount deviation count Xq is larger than or equal to a reference transient injection amount deviation count X2. If it is determined that the engine is in the transient state, the controller controls an EGR unit and a boost controller according to an excess air ratio that is an indicator indicating the state of the engine.

In a method for controlling an engine, based on a control map of an engine speed N and a fuel injection amount Q of a common-rail fuel injection unit, a controller calculating the fuel injection amount Q depending on the engine speed N, calculating an injection amount deviation Qn as a fuel injection amount increase, and determining that an engine is in a transient state if the injection amount deviation Qn exceeds a reference transient injection amount deviation A2 or if a transient injection amount deviation count Xq is larger than or equal to a reference transient injection amount deviation count X2. If it is determined that the engine is in the transient state, the controller controls an EGR unit and a boost controller according to an excess air ratio that is an indicator indicating the state of the engine.

A control apparatus for an engine includes an engine, an EGR system, a spark plug, a controller, and a supercharging system. While a supercharging system is performing supercharging and the EGR system is introducing burned gas into a combustion chamber, in response to a control signal from the controller, the spark plug ignites air-fuel mixture at predetermined timing so that unburned air-fuel mixture combusts by autoignition after the air-fuel mixture starts to combust by the ignition.

A control apparatus for an engine includes an engine, an EGR system, a spark plug, a controller, and a supercharging system. While a supercharging system is performing supercharging and the EGR system is introducing burned gas into a combustion chamber, in response to a control signal from the controller, the spark plug ignites air-fuel mixture at predetermined timing so that unburned air-fuel mixture combusts by autoignition after the air-fuel mixture starts to combust by the ignition.