An ignition timing control device for an internal combustion engine includes a storage device and a processor. The storage device stores a first learned neural network and a second learned neural network. The processor is configured to perform, in a next cycle where ignition timing is delayed, control to delay the ignition timing in a cycle after the next cycle based on a difference between a predictive value of an estimate of a value representing knocking intensity calculated with use of the second learned neural network and the estimate of the value representing the knocking intensity calculated with use of the first learned neural network. When the difference is larger than a predetermined set value, the processor is configured not to perform the control to delay the ignition timing in the cycle after the next cycle.

Provided is a control device of an internal combustion engine that reduces the number of times of discharge in multiple discharge by an ignition plug of the internal combustion engine and suppresses an error in fuel ignition by the ignition plug. The control device according to the present invention includes an ignition plug provided in a cylinder of an internal combustion engine, and an ignition control unit which has an ignition control function of controlling discharge (ignition) of the ignition plug and an ignition detection function of detecting ignition of an air-fuel mixture through ignition by the ignition plug. The ignition control unit is configured to stop ignition by the ignition plug on the basis of detection of ignition of the air-fuel mixture by the ignition plug.

Provided is a control device of an internal combustion engine that reduces the number of times of discharge in multiple discharge by an ignition plug of the internal combustion engine and suppresses an error in fuel ignition by the ignition plug. The control device according to the present invention includes an ignition plug provided in a cylinder of an internal combustion engine, and an ignition control unit which has an ignition control function of controlling discharge (ignition) of the ignition plug and an ignition detection function of detecting ignition of an air-fuel mixture through ignition by the ignition plug. The ignition control unit is configured to stop ignition by the ignition plug on the basis of detection of ignition of the air-fuel mixture by the ignition plug.

An ignition timing control device for an internal combustion engine includes a storage device and a processor. The storage device stores a first learned neural network and a second learned neural network. The processor is configured to perform, in a next cycle where ignition timing is delayed, control to delay the ignition timing in a cycle after the next cycle based on a difference between a predictive value of an estimate of a value representing knocking intensity calculated with use of the second learned neural network and the estimate of the value representing the knocking intensity calculated with use of the first learned neural network. When the difference is larger than a predetermined set value, the processor is configured not to perform the control to delay the ignition timing in the cycle after the next cycle.

The subject matter of this specification can be embodied in, among other things, a method of igniting an air/fuel mixture in an internal combustion engine includes receiving an air/fuel mixture into a pre-combustion chamber, the pre-combustion chamber enclosing a portion of an igniter, igniting the air/fuel mixture in in the pre-combustion chamber with the igniter to produce a flame, directing the flame to eject the pre-combustion chamber through a collection of passages in a wall of the pre-combustion chamber, toward a peripheral wall of a main combustion chamber of the internal combustion engine, igniting, by the flame, air/fuel mixture in the main combustion chamber adjacent the peripheral wall, and then igniting air/fuel mixture in the main combustion chamber in a central region of the main combustion chamber with a propagating flame front of the ignited air/fuel mixture or a portion of the directed flame adjacent the peripheral wall.

A control device for controlling an engine including an injector that supplies fuel into a cylinder and an in-cylinder pressure sensor that detects an in-cylinder pressure being a pressure inside the cylinder, is provided. The device includes a processor configured to execute an abnormal combustion determining module to determine whether combustion of a mixture gas inside the cylinder is abnormal based on a detection value of the in-cylinder pressure sensor. The abnormal combustion determining module determines that an abnormal combustion has occurred in which progress of the combustion of the mixture gas is excessively fast, when an in-cylinder pressure intensity that is a spectrum value of a frequency component of an in-cylinder pressure waveform less than a given reference frequency is greater than or equal to a given determination intensity, the in-cylinder pressure waveform being detected by the in-cylinder pressure sensor.

A control device for controlling an engine including an injector that supplies fuel into a cylinder and an in-cylinder pressure sensor that detects an in-cylinder pressure being a pressure inside the cylinder, is provided. The device includes a processor configured to execute an abnormal combustion determining module to determine whether combustion of a mixture gas inside the cylinder is abnormal based on a detection value of the in-cylinder pressure sensor. The abnormal combustion determining module determines that an abnormal combustion has occurred in which progress of the combustion of the mixture gas is excessively fast, when an in-cylinder pressure intensity that is a spectrum value of a frequency component of an in-cylinder pressure waveform less than a given reference frequency is greater than or equal to a given determination intensity, the in-cylinder pressure waveform being detected by the in-cylinder pressure sensor.

Provided is a control device for an internal combustion engine capable of estimating a compression ratio of the internal combustion engine at the time of fuel cut of the internal combustion engine and without being affected by an intake air amount and an intake air temperature. A compression ratio is calculated on the basis of a change of in-cylinder pressure P with respect to crank angle at timing when an in-cylinder volume change rate dV/d/V takes an extreme value or at timing from closing of an intake valve 109 to the start of ignition of the air-fuel mixture in the cylinder.

Provided is a control device for an internal combustion engine capable of estimating a compression ratio of the internal combustion engine at the time of fuel cut of the internal combustion engine and without being affected by an intake air amount and an intake air temperature. A compression ratio is calculated on the basis of a change of in-cylinder pressure P with respect to crank angle at timing when an in-cylinder volume change rate dV/d/V takes an extreme value or at timing from closing of an intake valve 109 to the start of ignition of the air-fuel mixture in the cylinder.

The subject matter of this specification can be embodied in, among other things, a method of igniting an air/fuel mixture in an internal combustion engine includes receiving an air/fuel mixture into a pre-combustion chamber, the pre-combustion chamber enclosing a portion of an igniter, igniting the air/fuel mixture in in the pre-combustion chamber with the igniter to produce a flame, directing the flame to eject the pre-combustion chamber through a collection of passages in a wall of the pre-combustion chamber, toward a peripheral wall of a main combustion chamber of the internal combustion engine, igniting, by the flame, air/fuel mixture in the main combustion chamber adjacent the peripheral wall, and then igniting air/fuel mixture in the main combustion chamber in a central region of the main combustion chamber with a propagating flame front of the ignited air/fuel mixture or a portion of the directed flame adjacent the peripheral wall.