摘要:
The procedure estimates the torque transmitted by a friction clutch coupled to the shaft of a motor vehicle engine and controlled by means of an actuator, the procedure comprising the operations of: measuring or otherwise determining the angular speed of the engine shaft and the torque developed by this shaft; calculating the difference or error between the measured value of the engine shaft's angular speed and an estimated value of the said angular speed; and, using an electronic controller, determining an estimated value of the torque transmitted by the clutch, corresponding to the calculated value of the said difference or error in the engine shaft angular speed; the estimated value of the torque transmitted by the clutch being used, along with the value measured or otherwise determined of the torque developed by the engine shaft, to obtain the said estimated value of the angular speed of the engine shaft on the basis of a predetermined mathematical model.
摘要:
A first clutch and a second clutch, which are operable selectively, control the coupling of the rotor of a reversible electrical machine with the transmission and with the internal combustion engine, respectively. A control system is provided for implementing a stop-start function in which, in a stop stage, the internal combustion engine is disconnected from the electrical machine and from the transmission and is switched off, in first predetermined operating conditions of the vehicle and then, as a result of the occurrence of second operating conditions, such as a command imparted by the driver, in a subsequent start stage, is automatically restarted by means of the electrical machine operating as a motor, and is then reconnected to the transmission. The system is characterized especially by particular methods of controlling the clutches and the electrical machine during the start stage.
摘要:
According to the method the crossover phase of the friction clutches is performed by defining a linear torque profile for the first friction clutch having a given initial value and a zero final value, a linear torque profile for the second friction clutch having a zero initial value and a given final value, and a linear torque profile for the engine having a given initial value and a given final value. The final value of the torque profile of the second friction clutch is calculated, the initial value of the engine torque being known, by determining a final value of the longitudinal acceleration of the vehicle equal to a given percentage of the initial value of the longitudinal acceleration of the vehicle. The final value of the engine torque profile is calculated, the final value of the torque profile of the second friction clutch being known, on the basis of the final value determined for the longitudinal acceleration of the vehicle. The initial value of the torque profile of the first friction clutch is chosen so as to be greater than a minimum value calculated by determining the condition of synchronism of the driving shaft and of the first primary shaft.
摘要:
The control system comprises detectors or estimators capable of supplying electrical signals or data indicative of the values of predetermined state variables including the angular velocity of the crankshaft of the engine, the difference between this angular velocity and the angular velocity of the primary shaft of the gearbox, and the torque delivered by the engine crankshaft and the torque transmitted by the friction clutch; calculating devices capable of supplying signals indicating the errors between the values of the state variables and respective reference values; filter devices capable of incrementing, within a predetermined frequency band, the relative weight selectively of the error of angular velocity of the crankshaft of the engine, and of the error of the abovementioned difference of angular velocity; processing devices capable of generating, in accordance with predetermined transfer functions, output signals or data indicating a torque partial value or contribution to be delivered by the engine and a torque partial value or contribution to be transmitted to the primary shaft of the gearbox by the friction clutch; and an adder capable of adding the torque partial values or contributions to corresponding other torque partial values or contributions, to be delivered or transmitted as relevant, determined by predetermined methods, in order to supply in the total output signals or data indicating the torque to be generated in the engine crankshaft and signals or data indicating the torque to be transmitted by the friction clutch.
摘要:
The control apparatus comprises, in its version intended for a double-clutch transmission with six or seven forward gears and one reverse gear, a first shift fork for engaging the first gear or the third gear, respectively, a second shift fork for engaging the reverse gear or the fifth gear, respectively, a first hydraulic actuator arranged to control the movement of the first shift fork, a second hydraulic actuator arranged to control the movement of the second shift fork, a selection slide valve which can be moved into a first operating position in which the first hydraulic actuator is selected and a second operating position in which the second hydraulic actuator is selected, a pilot solenoid valve for controlling the movement of the slide valve between the first and second operating positions, and first and second gear shift solenoid valves for controlling the supply of fluid to the hydraulic actuator each time selected by the slide valve or the connection of said actuator with a tank. The slide valve is configured in such a manner that the first and second operating positions are end-of-travel positions, wherein the first operating position is a rest position, in which the pilot solenoid valve does not generate any hydraulic pilot control signal and the slide valve is held by resilient means against a first mechanical stop, and wherein the second operating position is a maximum-control position, in which the pilot solenoid valve generates a hydraulic control signal such that the slide valve is brought against a second mechanical stop opposite to the first one.
摘要:
The gearbox comprises an engagement sleeve movable between a neutral position and one engagement position for engagement of one given gear, and a shift fork operatively connected to the engagement sleeve for controlling the movement thereof between the neutral position and the engagement position. The shift fork is slidably mounted on a stationary support rod, which is provided with a pair of bushes defining a first axial abutment surface for stopping the movement of the shift fork in the direction from the neutral position to the engagement position and a second axial abutment surface for stopping the movement of the shift fork in the direction from the engagement position to the neutral position. The neutral position of the shift fork is axially spaced from the second axial abutment surface.
摘要:
The method comprises the steps of: storing a curve or characteristic of torque transmitted by the friction clutch as a function of the position of the clutch, calculating a desired value of the torque to be transmitted by means of the clutch, and modifying the position of the clutch so as to bring it to the position to which the desired transmitted torque value corresponds according to the stored curve or characteristic, upon the occurrence of predetermined operative conditions, estimating the value of the torque transmitted by the clutch, by means of an algorithm, as a function of the detected instantaneous values of the torque delivered and of the angular velocity of the shaft of the engine, and detecting the corresponding instantaneous position or estimate position of the clutch, and then modifying the previously stored curve or characteristic in accordance with predetermined procedures in dependence on the difference between the estimated value of the torque transmitted and that value of the torque transmitted which corresponds to the estimate position according to the previously stored curve or characteristic.
摘要:
The control apparatus comprises, in its version intended for a double-clutch transmission, first, second and third shift forks each movable between first and second engagement positions to engage a respective gear, of which the first shift fork is able to engage at least the first gear and the second shift fork is able to engage at least the second gear, first, second and third double-acting hydraulic actuators arranged to control each the movement of a respective shift fork between the first and second engagement position, of which the first hydraulic actuator is associated to the first shift fork and the second hydraulic actuator is associated to the second shift fork, a slide valve selectively movable into one of at least three operating positions in each of which the slide valve selects a respective hydraulic actuator, and first and second gear shift solenoid valves for controlling the supply of fluid to the hydraulic actuator each time selected by the slide valve or the connection of that actuator to a tank. The first shift fork is moved into the engagement position of the first gear upon energization of the first gear shift solenoid valve, whereas the second shift fork is moved into the engagement position of the second gear upon energization of the second gear shift solenoid valve.
摘要:
The system comprises control devices (CS) arranged to implement a stop-start function in which, during a stop stage, the internal combustion engine (1) is disconnected from the electric machine (4) and from the transmission system (2) and is switched off in first predetermined operating conditions of the vehicle (V) and then, in a subsequent start stage, is automatically restarted by an electric machine (4), operating as a motor, and is then reconnected to the transmission system (2).
摘要:
The control apparatus comprises, in its version intended for a double-clutch transmission, first, second and third shift forks each movable between first and second engagement positions to engage a respective gear, of which the first shift fork is able to engage at least the first gear and the second shift fork is able to engage at least the second gear, first, second and third double-acting hydraulic actuators arranged to control each the movement of a respective shift fork between the first and second engagement position, of which the first hydraulic actuator is associated to the first shift fork and the second hydraulic actuator is associated to the second shift fork, a slide valve selectively movable into one of at least three operating positions in each of which the slide valve selects a respective hydraulic actuator, and first and second gear shift solenoid valves for controlling the supply of fluid to the hydraulic actuator each time selected by the slide valve or the connection of that actuator to a tank. The first shift fork is moved into the engagement position of the first gear upon energization of the first gear shift solenoid valve, whereas the second shift fork is moved into the engagement position of the second gear upon energization of the second gear shift solenoid valve.