Abstract:
A system is described for the diagnosis of a driver (D) of the type adapted to detect one or more circuit anomalies which can occur in the said driver, including:
voltage comparator circuits (10, 20) adapted to generate diagnostic logic signals (F 1 , F 2 , F 3 ) each indicative of the existence of a corresponding type of anomaly; and a coding circuit (M, SM) adapted to receive these diagnostic signals (F 1 , F 2 , F 3 ) and to output information relating to an overall operating state of the circuit. The coding circuit (M, SM) includes a first portion adapted to provide at its output first logic signals (SHB, SHG, OL) indicative of the last anomaly occurred since a system reset operation, and a second portion for coding such first logic signals (SHB, SHG, OL). The second portion includes a sequential logic network (SM) adapted to:
receive the first logic input signals (SHB, SHG, OL) and at least one second logic signal (IN) indicative of the current operating phase of the driver (D); and achieve, as a function of the said first and second logic signals (SHB, SHG, OL; IN) a stable internal state such as to determine at the output information in the form of an N bit coded word representative of an occurred anomaly, of a condition of absence of anomaly in the current operating phase, or of a condition of absence of anomaly in any operating phase.
Abstract:
A method for refreshing the injection law of a fuel injector (4) to be tested in an injection system; the method includes the steps of: establishing the desired fuel quantity (Qd) for the fuel injector (4) to be tested; performing at least one first measurement opening of the fuel injector (4) to be tested in a test actuation time (T); determining a pressure drop (ΔP) in a common rail (5) during the first measurement opening of the fuel injector (4) to be tested; determining a first fuel quantity (Q1) which is fed during the first measurement opening; calculating a second fuel quantity (Q2) as the difference between the desired fuel quantity (Qd) and the first fuel quantity (Q1); and performing a second completion opening of the fuel injector (4) to be tested for feeding the second fuel quantity (Q2) needed to reach the desired fuel quantity (Qd).
Abstract:
A method for controlling fuel injection in a multifuel internal-combustion engine (1) that can inject alternatively a liquid fuel and a gaseous fuel; the control method envisages the steps of: injecting the gaseous fuel by means of at least one corresponding injector (15); cyclically measuring the pressure (P rail ) of the gaseous fuel within the common channel (22); determining at least one upper-limit threshold (P rail-min ; P rail-max ) for the pressure (P rail ) of the gaseous fuel within the common channel (22); comparing the pressure (P rail ) of the gaseous fuel within the common channel (22) with the upper-limit threshold (P rail-min ; P rail-max ); and carrying out an automatic fuel switch from the gaseous fuel to the liquid fuel when the pressure (P rail ) of the gaseous fuel within the common channel (22) exceeds the upper-limit threshold (P rail-min ; Prail-max).
Abstract:
A method for detecting a misfire condition in an internal combustion engine (1) provided with a driving shaft (4) to which a phonic wheel (5) is splined, which phonic wheel (5) is coupled to a sensor (7); the method is characterized by detecting the intensity of the signal (S) generated by the passage of the teeth (6) of the phonic wheel (5) by means of the sensor (7); sampling the signal (S) generated by the passage of the teeth (6) of the phonic wheel (5); processing the sampled signal (S) by applying a Discrete Fourier Transform (DFT); determining the presence of a misfire condition as a function of the signal (S) which has been sampled and processed by means of the Discrete Fourier Transform.
Abstract:
The method of diagnosis determines the state of deterioration of an exhaust gas stoichiometric composition sensor placed downstream of a catalytic converter. The catalytic converter is mounted on an exhaust manifold of an internal combustion engine supplied with an air/fuel mixture, while the sensor generates an output signal correlated with the stoichiometric composition of the mixture. The method comprises the phases of registering a temperature signal correlated with the temperature of the engine; determining the operating range of the engine; determining the stoichiometric composition of the air/fuel mixture; and effecting a hot diagnosis should the temperature signal be greater than a preset reference value, the engine be in the idle operating range and the sensor register a weak stoichiometric composition of the mixture. The hot diagnosis comprises the phases of generating control signals for the engine and of gauging the output signal from the sensor.
Abstract:
A method for controlling the movement of a component that moves towards a position defined by a limit stop in an internal combustion engine (1); the control method comprises the steps of detecting, by means of at least one acoustic microphone (22), the intensity (S) of the microphonic signal generated by the impact of the component against the limit stop; and determining the impact instant and/or the impact speed of the component against the limit stop by analyzing the intensity (S) of the microphonic signal generated by the impact.
Abstract:
A method for controlling the wastegate (16) in a turbocharged internal combustion engine (1); the method contemplates the steps of: determining, during a design phase, a control law (CL) which provides an objective opening of a controlling actuator (35) of the wastegate (16) according to the supercharging pressure (P); determining an objective supercharging pressure (P obj ); measuring an actual supercharging pressure (P); determining a first open loop contribution (WG OL ) of an objective position (WG obj ) of a controlling actuator (35) of the wastegate (16) by means of the control law (CL) and according to the objective supercharging pressure (P obj ); determining a second closed loop contribution (WG CL1 ) of the objective position (WG obj ) of the controlling actuator (35) of the wastegate (16); and calculating the objective position (WG obj ) of the controlling actuator (35) of the wastegate (16) by adding the two contributions (WG OL ,WG CL1 ).