Abstract: A device and a method for determining the trouble of a cylinder pressure sensor without increasing cost calculates the cylinder pressure of an internal combustion engine based on an output from the cylinder sensor installed in the engine and calculates a drift parameter indicating the drift amount of the cylinder pressure based on the cylinder pressure. When the drift parameter is not within a specified range, the device determines that the cylinder pressure sensor is defective. The specified range can be set based on the behavior of the cylinder pressure. A correction factor is obtained according to the operating state of the engine, and the drift parameter is corrected with the correction factor. A specified search signal is superimposed on the output from the cylinder pressure sensor. The cylinder pressure is calculated based on the output from the cylinder pressure sensor on which the search signal was superimposed.

Abstract: Work done by an engine can be accurately calculated regardless of the part in an observation section where the cylinder internal pressure signal is detected. The apparatus for calculating the work done by an engine establishes in advance correlation of phase between the cylinder internal pressure of the engine and a reference signal composed of a predetermined frequency component as a reference phase relation. A means for detecting the cylinder internal pressure of the engine for a predetermined observation section is provided. A reference signal corresponding to the detected cylinder internal pressure of the engine is calculated so that the reference phase relation is satisfied. A correlation coefficient of the detected cylinder internal pressure of the engine and the calculated reference signal is calculated for the observation section and the work done by the engine is calculated in accordance with the correlation coefficient.

Abstract: A device and method for calculating the work load of an engine more efficiently and accurately. The device for calculating the work load of an engine comprises a means for determining a desired frequency component to calculate the work load of the engine obtained through frequency decomposition of the volume variation rate of the engine. The device further comprises a first calculating means for calculating a first correlation coefficient between the volume variation rate and a reference signal composed of a frequency corresponding to the determined component, and a second calculating means for calculating a second correlation coefficient between the cylinder inner pressure of the engine and a reference signal composed of a frequency corresponding to the determined component. The work load of the engine is calculated using the first and second correlation coefficients.

Abstract: Work done by an engine can be accurately calculated regardless of the part in an observation section where the cylinder internal pressure signal is detected. The apparatus for calculating the work done by an engine establishes in advance correlation of phase between the cylinder internal pressure of the engine and a reference signal composed of a predetermined frequency component as a reference phase relation. A means for detecting the cylinder internal pressure of the engine for a predetermined observation section is provided. A reference signal corresponding to the detected cylinder internal pressure of the engine is calculated so that the reference phase relation is satisfied. A correlation coefficient of the detected cylinder internal pressure of the engine and the calculated reference signal is calculated for the observation section and the work done by the engine is calculated in accordance with the correlation coefficient.

Abstract: A workload calculation apparatus and method for an internal combustion engine, and an engine control unit are provided for accurately calculating a workload parameter indicative of the workload of the internal combustion engine.

Abstract: A device and method for calculating the work load of an engine more efficiently and accurately. The device for calculating the work load of an engine comprises a means for determining a desired frequency component to calculate the work load of the engine obtained through frequency decomposition of the volume variation rate of the engine. The device further comprises a first calculating means for calculating a first correlation coefficient between the volume variation rate and a reference signal composed of a frequency corresponding to the determined component, and a second calculating means for calculating a second correlation coefficient between the cylinder inner pressure of the engine and a reference signal composed of a frequency corresponding to the determined component. The work load of the engine is calculated using the first and second correlation coefficients.

Abstract: A failure detection apparatus for preventing erroneous detection due to a degradation of a sensor and thereby accurately performing failure detection of a variable valve timing and lift control system is provided. The detection apparatus detects a failure of a variable valve timing and lift control system in an engine. The detection apparatus detects a vibration inside an engine cylinder, extracts the component of seating sound of the valve from the output signal of the sensor, determines an actual seating time of said valve from the component of seating sound, and calculates a target seating time of said valve based on at least one of a requested lift amount, a requested advance angle, and a requested open angle depending on the operating conditions. The detecting apparatus corrects the actual seating time for a stationary deviation between the actual seating time and the target seating time caused by degradation or unevenness of the sensor.

Abstract: A device and a method for determining the trouble of a cylinder pressure sensor. The device accurately detecting the trouble of the cylinder sensor without increasing cost calculates the cylinder pressure of an internal combustion engine based on an output from the cylinder sensor installed in the internal combustion engine and calculates a drift parameter indicating the drift amount of the cylinder pressure based on the cylinder pressure. When the drift parameter is not within a specified range, the device determines that the cylinder pressure sensor is defective. According to one embodiment, the specified range can be set based on the behavior of the cylinder pressure. According to the other embodiment, a correction factor is obtained according to the operating state of the internal combustion engine, and the drift parameter is corrected with the correction factor.

Abstract: A method of calculating the amount of work done by an internal combustion engine, which is capable of calculating a work amount parameter indicative of the amount of work done with accuracy while compensating for a phase delay in in-cylinder pressure data caused e.g. by a filtering process performed thereon. The method calculates the work amount parameter Pmi indicative of the amount of work done by the engine 3 including a combustion chamber 3b, as follows: Pressure in the combustion chamber 3b is detected to obtain in-cylinder pressure data P indicative of the detected pressure. Volume data V indicative of a state of change in volume of the combustion chamber 3b is obtained. The obtained volume data V is subjected to a first predetermined filtering process. The work amount parameter Pmi is calculated based on the detected in-cylinder pressure data P, and the volume data filtered value VF obtained by subjecting the volume data V to the first filtering process.

Abstract: An in-cylinder pressure sensor for outputting a signal corresponding to an internal cylinder pressure of an engine is provided. A first signal and a second signal are extracted from the output signal of the in-cylinder pressure sensor. The first signal has a frequency band corresponding to knocking of the engine. The second signal has a frequency band used for detecting a peak of the internal cylinder pressure. A knocking detection period is set based on the second signal. The first signal in the knocking detection period is examined to determine whether or not knocking has occurred.

Abstract: A workload calculation apparatus and method for an internal combustion engine, and an engine control unit are provided for accurately calculating a workload parameter indicative of the workload of the internal combustion engine.

Abstract: A failure detection apparatus for preventing erroneous detection due to a degradation of a sensor and thereby accurately performing failure detection of a variable valve timing and lift control system is provided. The detection apparatus detects a failure of a variable valve timing and lift control system in an engine. The detection apparatus detects a vibration inside an engine cylinder, extracts the component of seating sound of the valve from the output signal of the sensor, determines an actual seating time of said valve from the component of seating sound, and calculates a target seating time of said valve based on at least one of a requested lift amount, a requested advance angle, and a requested open angle depending on the operating conditions. The detecting apparatus corrects the actual seating time for a stationary deviation between the actual seating time and the target seating time caused by degradation or unevenness of the sensor.

Abstract: An in-cylinder pressure sensor outputs a signal corresponding to a change rate of an internal cylinder pressure of an engine. The output signal of the in-cylinder pressure sensor is filtered so that frequency components lower than frequencies that substantially compose an internal cylinder pressure required for controlling the engine are cut. The filtered output signal is integrated to determine the internal cylinder pressure. Thus, an internal cylinder pressure having no drift can be determined.

Abstract: A control apparatus for an internal combustion engine that is capable of switching between compression ignition combustion and spark ignition combustion is provided. The control apparatus is configured to perform fuel cut. The spark ignition combustion is performed over a time period after the fuel cut. The compression ignition combustion is permitted when the time period elapses. Fuel cut decreases the temperature within the combustion chamber. According to the invention, if fuel cut is performed, the temperature within the combustion chamber is raised by the spark ignition combustion. Since the compression ignition combustion is permitted after the temperature within the combustion chamber rises, engine misfire and an increase of NOx emission are prevented. The time period is preferably determined based on the temperature within the combustion chamber immediately before the fuel cut is performed.

Abstract: An apparatus for detecting an in-cylinder pressure of an engine is provided. The apparatus comprises an in-cylinder pressure sensor for outputting a signal indicating a change rate of an in-cylinder pressure and a control unit. The control unit is configured to correct the signal from the in-cylinder pressure sensor, integrate the corrected signal to determine the in-cylinder pressure, determine a change rate of a drift contained in the determined in-cylinder, and feedback the change rate of the drift so that the correction of the signal is made with the change rate of the drift. Since the output of the in-cylinder pressure sensor from which a drift has been removed is integrated, it is prevented that a drift appears in the in-cylinder pressure obtained by the integral. A resetting operation is not required so as to remove a drift.

Abstract: The present invention aims at expanding an operation range for allowing a compression ignition combustion operation. The present invention provides an internal combustion engine of a compression ignition type that is capable of operating with a compression ignition combustion scheme in a given operation range. The ECU of the internal combustion engine detects an operating condition of the internal combustion engine and determines, according to the detected operating condition, which mode is to be used operate the internal combustion engine, a 4-cycle compression ignition mode or a 2-cycle compression ignition mode. The ECU controls the internal compression engine to perform the compression ignition mode determined.

Abstract: An in-cylinder pressure sensor outputs a signal corresponding to a change rate of an internal cylinder pressure of an engine. The output signal of the in-cylinder pressure sensor is filtered so that frequency components lower than frequencies that substantially compose an internal cylinder pressure required for controlling the engine are cut. The filtered output signal is integrated to determine the internal cylinder pressure. Thus, an internal cylinder pressure having no drift can be determined.

Abstract: An in-cylinder pressure sensor for outputting a signal corresponding to an internal cylinder pressure of an engine is provided. A first signal and a second signal are extracted from the output signal of the in-cylinder pressure sensor. The first signal has a frequency band corresponding to knocking of the engine. The second signal has a frequency band used for detecting a peak of the internal cylinder pressure. A knocking detection period is set based on the second signal. The first signal in the knocking detection period is examined to determine whether or not knocking has occurred.

Abstract: A controller for an internal combustion engine capable of performing a compression ignition operation. The internal combustion engine includes a combustion chamber, and a fuel injector for injecting fuel directly in the combustion chamber. The controller includes: an air pressure detecting unit configured to detect at least one of an air pressure and an exhaust air pressure; and a fuel injection control unit configured to actuate the fuel injector to control a fuel injection timing according to a detected result by the air pressure detecting unit. The fuel injection control unit puts the fuel injection timing forward as the detected result by the air pressure detecting unit is lowered.

Abstract: A method of calculating the amount of work done by an internal combustion engine, which is capable of calculating a work amount parameter indicative of the amount of work done with accuracy while compensating for a phase delay in in-cylinder pressure data caused e.g. by a filtering process performed thereon. The method calculates the work amount parameter Pmi indicative of the amount of work done by the engine 3 including a combustion chamber 3b, as follows: Pressure in the combustion chamber 3b is detected to obtain in-cylinder pressure data P indicative of the detected pressure. Volume data V indicative of a state of change in volume of the combustion chamber 3b is obtained. The obtained volume data V is subjected to a first predetermined filtering process. The work amount parameter Pmi is calculated based on the detected in-cylinder pressure data P, and the volume data filtered value VF obtained by subjecting the volume data V to the first filtering process.