A method of controlling an engine is provided, the method including the steps of injecting main fuel by a fuel injector during an intake stroke or a compression stroke, providing a mixture gas containing fuel and air inside a cylinder, applying by an ignition device a high voltage between electrodes of a spark plug at a timing when the mixture gas is not ignited, detecting a parameter related to a current value of an electric-discharge channel generated between the electrodes, determining whether the detected parameter is within a range between a first threshold and a second threshold to determine a flowing state of a vortex inside the cylinder, injecting supplemental fuel by the fuel injector after the main fuel injection when the parameter is determined to be outside the range, and igniting the mixture gas by the ignition device using the spark plug after the supplemental fuel injection.

The present application provides a spark plug testing tool for a spark plug assembly of a gas turbine engine combustor. The spark plug testing tool may include a dielectric tube attached to the spark plug assembly and a first support bracket to support the spark plug assembly and the dielectric tube therein such that the spark plug assembly remains electrically connected to the gas turbine engine combustor during testing.

The present application provides a spark plug testing tool for a spark plug assembly of a gas turbine engine combustor. The spark plug testing tool may include a dielectric tube attached to the spark plug assembly and a first support bracket to support the spark plug assembly and the dielectric tube therein such that the spark plug assembly remains electrically connected to the gas turbine engine combustor during testing.

It is disclosed an electronic device to control an ignition coil of an internal combustion engine comprising a high-voltage switch, a driving unit, a bias circuit and an integrating circuit. The high-voltage switch is connected in series with a primary winding of a coil. The driving unit is configured to control the closing and opening of the high-voltage switch. The integrating circuit is interposed between the bias circuit and a reference voltage. The integrating circuit comprises an integrating capacitor. The integrating capacitor is configured, in the case wherein a pre-ignition of the comburent-combustible mixture in the combustion chamber during the phase of charging occurs, to pre-charge during the phase of charging energy in the primary winding and it is configured, in the case wherein the pre-ignition of the comburent-combustible mixture does not occur, to maintain the charge state substantially constant during the phase of charging energy.

It is disclosed an electronic device to control an ignition coil of an internal combustion engine comprising a high-voltage switch, a driving unit, a bias circuit and an integrating circuit. The high-voltage switch is connected in series with a primary winding of a coil. The driving unit is configured to control the closing and opening of the high-voltage switch. The integrating circuit is interposed between the bias circuit and a reference voltage. The integrating circuit comprises an integrating capacitor. The integrating capacitor is configured, in the case wherein a pre-ignition of the comburent-combustible mixture in the combustion chamber during the phase of charging occurs, to pre-charge during the phase of charging energy in the primary winding and it is configured, in the case wherein the pre-ignition of the comburent-combustible mixture does not occur, to maintain the charge state substantially constant during the phase of charging energy.

The internal-combustion-engine combustion state control apparatus includes an ignition control means that generates two or more ignition signals during a single compression stroke or a single combustion stroke of an internal combustion engine, a high voltage means that makes an ignition plug, provided in a combustion chamber of the internal combustion engine, perform an ignition discharge based on the ignition signal, an ignition-discharge parameter detection circuit that detects a parameter indicating a state of the ignition discharge, an ignition-discharge duration detection means that detects two or more ignition discharge durations, based on an output signal of the ignition-discharge parameter detection circuit, and an abnormal-combustion determination means that diagnoses a combustion state of the internal combustion engine, based on at least one of the two or more ignition discharge durations; an abnormal-combustion-suppression control means is made to operate based on the result of a determination by the abnormal-combustion determination means.

An ignition device for an internal combustion engine includes a switching circuit and a control circuit. The control circuit monitors a voltage level inputted to a switching device which is installed in the switching circuit and connected to a primary winding of an ignition coil. The control circuit includes an overvoltage protection circuit which outputs an energization inhibit signal to inhibit energization of the switching device when the monitored voltage level is higher than an overvoltage threshold level. When the monitored voltage level exceeds the overvoltage threshold level in an output duration in which the energization control signal is outputted, the overvoltage protection circuit stops output of the energization inhibit signal until the output duration expires. This enables the switching device to be protected from damage and an ignition operation to be executed at a correct timing to eliminate a risk of damage to the internal combustion engine.

An ignition device for an internal combustion engine includes a switching circuit and a control circuit. The control circuit monitors a voltage level inputted to a switching device which is installed in the switching circuit and connected to a primary winding of an ignition coil. The control circuit includes an overvoltage protection circuit which outputs an energization inhibit signal to inhibit energization of the switching device when the monitored voltage level is higher than an overvoltage threshold level. When the monitored voltage level exceeds the overvoltage threshold level in an output duration in which the energization control signal is outputted, the overvoltage protection circuit stops output of the energization inhibit signal until the output duration expires. This enables the switching device to be protected from damage and an ignition operation to be executed at a correct timing to eliminate a risk of damage to the internal combustion engine.

It is disclosed an electronic device to control an ignition coil of an internal combustion engine, comprising a high-voltage switch, a driving unit, a bias circuit and an integrating circuit. The high-voltage switch is connected in series with a primary winding of a coil. The driving unit is configured to control the closing and opening of the high-voltage switch. The integrating circuit is interposed between the bias circuit and a reference voltage. The integrating circuit comprises an integrating capacitor connected in series to the bias circuit and connected between the bias circuit and the reference voltage. The integrating capacitor is configured to maintain a substantially null charge during a phase of measurement of a ionization current as to measure a substantially null value of an integral of the ionization current, in the case of a misfire of the comburent-combustible mixture.

Provided is an ignition system including: a main primary coil; a main IC configured to switch a main primary coil mode between an energization mode and a de-energization mode; a sub primary coil; a sub IC configured to switch a sub primary coil mode between an energization mode and a de-energization mode; a secondary coil; a detection unit configured to detect a state of the main primary coil; and a control unit configured to determine whether a state of a sub primary current path is normal or abnormal based on the state of the main primary coil detected by the detection unit, the sub primary current path being a current path of a sub primary current flowing through the sub primary coil.