Abstract: System for controlling the operation of a motor vehicle diesel engine in which the supply of fuel to the cylinders is controlled as a function of the pressure of a reference cylinder acquired and a predetermined desired fuel supply value for each cylinder, the supply of fuel to the reference cylinder is slaved to its desired supply value as a function of the pressure acquired, the drive shaft rotation speed generated by the displacement of the piston of the reference cylinder and the drive shaft rotation speed generated by the displacement of the piston of at least one other cylinder are acquired, and the supply of fuel to this at least one other cylinder is actuated as a function of the speeds acquired by slaving the drive shaft rotation speed related to the at least one other cylinder to the drive shaft rotation speed related to the reference cylinder.

Abstract: A method is provided for determining whether an injection parameter correction for fuel quality is required in an internal combustion engine, the engine comprising a plurality of cylinders, each one of the cylinders comprising a combustion chamber into which fuel is injected by an associated fuel injector and within which, in use, combustion events repeatedly occur to define a combustion cycle of the cylinder between successive combustion events. The method comprises observing the speed of the combustion cycles of at least two of the cylinders and analysing the at least two speeds to determine if an injection parameter correction for fuel quality is required. The invention also extends to an injector control unit arranged to determine an injection parameter correction for fuel quality.

Abstract: A method is provided for determining whether an injection parameter correction for fuel quality is required in an internal combustion engine, the engine comprising a plurality of cylinders, each one of the cylinders comprising a combustion chamber into which fuel is injected by an associated fuel injector and within which, in use, combustion events repeatedly occur to define a combustion cycle of the cylinder between successive combustion events. The method comprises observing the speed of the combustion cycles of at least two of the cylinders and analysing the at least two speeds to determine if an injection parameter correction for fuel quality is required. The invention also extends to an injector control unit arranged to determine an injection parameter correction for fuel quality.

Abstract: A process for determining the operating parameters of an injection device of a combustion engine includes the steps of: (a) selecting an injector to test; (b) calculating a mean velocity associated with a preceding injector arranged before the injector to test; c) applying to the injector to test an injection control signal including at least one test pulse having an adjustable parameter; (d) calculating a mean velocity associated with the injector to test; (e) calculating a difference between the mean velocity calculated in step d) and the mean velocity calculated in step b); (f) repeating steps b) to d) for at least another engine cycle, each time varying the parameter of the test pulse; (g) determining a value of the parameter of the test pulse for which the mean velocity difference exceeds a predetermined threshold; and storing the parameter value.

Abstract: A system for controlling the operation of a diesel engine of a motor vehicle comprising means for supplying fuel to the cylinders thereof, the system comprising means for acquiring the pressure of a reference cylinder and means for controlling the supply means as a function of the pressure acquired and a predetermined desired fuel supply value for each cylinder, wherein the control means includes slaving means suitable for slaving the supply of fuel to the reference cylinder to its desired supply value as a function of the pressure acquired, means for acquiring the drive shaft rotation speed generated by the displacement of the piston of the reference cylinder and the drive shaft rotation speed generated by the displacement of the piston of at least one other cylinder and actuating means suitable for actuating the supply of fuel to this at least one other cylinder as a function of the speeds acquired by slaving the drive shaft rotation speed generated by the displacement of the piston of this at least one oth

Abstract: A system for controlling the operation of a diesel engine of a motor vehicle equipped with means for supplying fuel to the cylinders thereof in accordance with at least one main injection and a delayed injection of fuel as a function of a predetermined desired value for the crank angle interval separating the delayed injection from the main injection, wherein it comprises means for estimating the crank angle interval separating the delayed injection from the main injection in at least one cylinder and means for controlling the supply means capable of slaving this estimated interval to the desired interval value.

Abstract: The invention relates to a system for calibrating apparatus (28) for acquiring the pressure in a cylinder (10) of a motor vehicle diesel engine, of the type comprising a cylinder pressure sensor (30) associated with the cylinder and means (32) for conditioning the signal delivered by the sensor (30) as a function of conditioning parameters.

Abstract: In the method of diagnosing the operating state of a motor vehicle diesel engine of the invention, the engine includes a pressure acquisition system associated with each cylinder of the engine to acquire the pressure in that cylinder, an engine shaft angle acquisition system adapted to deliver the crankshaft angle of each cylinder, and onboard correction system adapted to correct a predetermined set of malfunctions and drifts of the cylinders and the acquisition systems. The method includes an analysis step of analyzing the operation of each cylinder and the cylinder pressure and engine shaft angle acquisition systems by identifying an operating state of the set comprising that cylinder and those systems based on predetermined characteristics of the signal delivered by the cylinder pressure acquisition system, and a correction step of correcting identified malfunctions and drifts.

Abstract: A process for determining the operating parameters of an injection device of a combustion engine includes the steps of: (a) selecting an injector to test; (b) calculating a mean velocity associated with a preceding injector arranged before the injector to test; c) applying to the injector to test an injection control signal including at least one test pulse having an adjustable parameter; (d) calculating a mean velocity associated with the injector to test; (e) calculating a difference between the mean velocity calculated in step d) and the mean velocity calculated in step b); (f) repeating steps b) to d) for at least another engine cycle, each time varying the parameter of the test pulse; (g) determining a value of the parameter of the test pulse for which the mean velocity difference exceeds a predetermined threshold; and storing the parameter value.

Abstract: The invention relates to a diesel engine comprising a device for controlling the flow of injected fuel with at least one fuel injector supplying a combustion chamber, controlled by a processor provided with means for controlling a series of operations of the injector of differing durations, means for measuring a minimal activation time (?TMA+?T) between the issuing of a command and the beginning of an injection and means for subsequently controlling the injector as a function of the measured minimal activation time. According to the invention, the engine is characterized in comprising means for determining the heat output (dQ) brought about by the mixture of air and fuel injected into the chamber and to measure the minimum activation time using said determinations.

Abstract: The invention relates to a method of diagnosing the operating state of a motor vehicle diesel engine (10), the engine (10) comprising a pressure acquisition system (18a, 18b, 18c, 18d) associated with each cylinder (12a, 12b, 12c, 12d) of the engine to acquire the pressure in that cylinder, an engine shaft angle acquisition system (30) adapted to deliver the crankshaft angle of each cylinder, and onboard correction means (34) adapted to correct a predetermined set of malfunctions and drifts of the cylinders and the acquisition systems, which method is characterized in that it comprises: an analysis step (102) of analyzing the operation of each cylinder and the cylinder pressure and engine shaft angle acquisition systems by identifying an operating state of the set comprising that cylinder and those systems as either a nominal operating state or one of a set of predetermined malfunctions and drifts based on predetermined characteristics of the signal delivered by the cylinder pressure acquisition system; an

Abstract: The invention relates to a system for calibrating apparatus (28) for acquiring the pressure in a cylinder (10) of a motor vehicle diesel engine, of the type comprising a cylinder pressure sensor (30) associated with the cylinder and means (32) for conditioning the signal delivered by the sensor (30) as a function of conditioning parameters.

Abstract: The invention relates to a diesel engine comprising a device for controlling the flow of injected fuel with at least one fuel injector supplying a combustion chamber, controlled by a processor provided with means for controlling a series of operations of the injector of differing durations, means for measuring a minimal activation time (?TMA+?T) between the issuing of a command and the beginning of an injection and means for subsequently controlling the injector as a function of the measured minimal activation time. According to the invention, the engine is characterized in comprising means for determining the heat output (dQ) brought about by the mixture of air and fuel injected into the chamber and to measure the minimum activation time using said determinations.

Abstract: This system for controlling the combustion noise of a motor vehicle diesel engine of the type including means for feeding each of its cylinders with fuel by multiple injections of fuel, which means are adapted to trigger fuel feed into each cylinder in the form of at least one pilot injection and a main injection of fuel, comprises: means for determining pressure gradients in the engine cylinder while in operation, at least during the pilot and main injection stages; and means for determining the quantity of fuel to be injected into the cylinder during pilot injection for a predetermined quantity of fuel injected during main injection so as to optimize a criterion based on the ratio between the pressure gradients corresponding to the pilot and main injection stages, thereby optimizing the operating noise of the engine.

Abstract: This system for controlling the combustion noise of a motor vehicle diesel engine of the type including means for feeding each of its cylinders with fuel by multiple injections of fuel, which means are adapted to trigger fuel feed into each cylinder in the form of at least one pilot injection and a main injection of fuel, comprises: means for determining pressure gradients in the engine cylinder while in operation, at least during the pilot and main injection stages; and means for determining the quantity of fuel to be injected into the cylinder during pilot injection for a predetermined quantity of fuel injected during main injection so as to optimize a criterion based on the ratio between the pressure gradients corresponding to the pilot and main injection stages, thereby optimizing the operating noise of the engine.

Abstract: A control method as described, the method being intended for use controlling the operation of a compression ignition internal combustion engine having an accelerometer associated therewith and arranged to sense vibrations of the engine, and a monitor arranged to monitor the output signal of the accelerometer, by monitoring the output signal during a detection time interval and a reference time interval, using the output signal during the reference time interval to compensate for background noise, and using the noise compensated signal in controlling the operation of the engine.