EP0637685B1 - Process and apparatus for auto-adaptation of air/fuel ratio in an internal combustion engine with canister purge system - Google Patents

Process and apparatus for auto-adaptation of air/fuel ratio in an internal combustion engine with canister purge system Download PDF

Info

Publication number
EP0637685B1
EP0637685B1 EP19940401643 EP94401643A EP0637685B1 EP 0637685 B1 EP0637685 B1 EP 0637685B1 EP 19940401643 EP19940401643 EP 19940401643 EP 94401643 A EP94401643 A EP 94401643A EP 0637685 B1 EP0637685 B1 EP 0637685B1
Authority
EP
European Patent Office
Prior art keywords
engine
adaptation
auto
air
shift
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP19940401643
Other languages
German (de)
French (fr)
Other versions
EP0637685A1 (en
Inventor
Marcel Colomby
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Marelli France SAS
Original Assignee
Magneti Marelli France SAS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Magneti Marelli France SAS filed Critical Magneti Marelli France SAS
Publication of EP0637685A1 publication Critical patent/EP0637685A1/en
Application granted granted Critical
Publication of EP0637685B1 publication Critical patent/EP0637685B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M25/00—Engine-pertinent apparatus for adding non-fuel substances or small quantities of secondary fuel to combustion-air, main fuel or fuel-air mixture
    • F02M25/08—Engine-pertinent apparatus for adding non-fuel substances or small quantities of secondary fuel to combustion-air, main fuel or fuel-air mixture adding fuel vapours drawn from engine fuel reservoir
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/003—Adding fuel vapours, e.g. drawn from engine fuel reservoir
    • F02D41/0032—Controlling the purging of the canister as a function of the engine operating conditions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/003—Adding fuel vapours, e.g. drawn from engine fuel reservoir
    • F02D41/0042—Controlling the combustible mixture as a function of the canister purging, e.g. control of injected fuel to compensate for deviation of air fuel ratio when purging
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
    • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
    • F02D41/2409—Addressing techniques specially adapted therefor
    • F02D41/2412—One-parameter addressing technique
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
    • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
    • F02D41/2425—Particular ways of programming the data
    • F02D41/2429—Methods of calibrating or learning
    • F02D41/2441—Methods of calibrating or learning characterised by the learning conditions
    • F02D41/2448—Prohibition of learning
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
    • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
    • F02D41/2425—Particular ways of programming the data
    • F02D41/2429—Methods of calibrating or learning
    • F02D41/2451—Methods of calibrating or learning characterised by what is learned or calibrated
    • F02D41/2454—Learning of the air-fuel ratio control

Definitions

  • the invention relates to a method of self-adaptation of the richness and authorization of the purge of a purge circuit comprising a canister, for an internal combustion engine, of the spark-ignition type, equipped with a supply installation.
  • injection fuel and therefore referred to as an injection engine in the remainder of this description, and preferably, but not exclusively, with a four-stroke engine cycle.
  • the fuel supply installation of such an injection engine comprises an air intake manifold to the engine, on the upstream of which a shutter for controlling the air flow, most often in disc shape, called butterfly, is rotatably mounted in a body.
  • the injection installation comprises at least one injector delivering fuel into the intake manifold.
  • the injector or each injector is supplied with fuel at a pressure given by a regulator, which drifts towards the injector a part of the fuel which it receives from the tank by a pump, and which returns to the tank the quantity of excess fuel by compared to that injected, which is a function of the duration of opening of the injector, called injection duration, and determined by a computer connected to sensors for operating parameters of the engine.
  • the computer generally receives signals representative of the engine water or coolant temperature, the air temperature in the intake manifold, the throttle opening angle, and above all it receives engine rotation signals, supplied for example by a sensor cooperating with a toothed wheel integral with the flywheel, and having a singularity, for example a missing tooth, for detecting dead center top (TDC) of a reference cylinder, allowing the computer to determine the injection phases or times in the different cylinders, the engine speed being calculated from the signal modulated by the movement of the teeth.
  • TDC dead center top
  • the computer can also receive a pressure signal measured directly in the intake manifold, or can calculate this pressure signal from two measurements chosen from the group comprising the throttle opening angle, the air flow and engine speed.
  • This computer which determines the instant and duration of injection of each injector, is generally simultaneously an engine control computer, fulfilling other command and control functions, and determining in particular the instants of ignition of the spark plugs of the engine cylinders.
  • a basic injection duration calculated essentially as a function of the engine speed and of the pressure in the manifold, it is known to provide regulation from the oxygen sensor by correcting this injection duration basic taking into account a richness coefficient KO2, determined, in particular by applying value transitions, as a function of the richness signal of the oxygen sensor in the engine operating zones in closed loop, and fixed equal to a nominal value in the case of open-loop motor operation, for example in low temperature operation (after starting the engine cold), or in deceleration, or at full load, and finally if the engine speed is above a given high threshold.
  • a richness coefficient KO2 determined, in particular by applying value transitions, as a function of the richness signal of the oxygen sensor in the engine operating zones in closed loop, and fixed equal to a nominal value in the case of open-loop motor operation, for example in low temperature operation (after starting the engine cold), or in deceleration, or at full load, and finally if the engine speed is above a given high threshold.
  • the richness coefficient KO2 by the computer makes it possible to increase or reduce the basic injection time, to center the operation of the engine on a richness equal to 1. Furthermore, it is known to express, for a given engine speed, the basic injection duration as a substantially linear function increasing, in the useful operating range of the engine, of the absolute pressure in the intake manifold, representing the engine torque, i.e. the engine load, and neglecting correction coefficients from maps, for example as a function of engine speed, pressure in the manifold or the throttle opening angle, to reflect the inflection of the straight in an S curve, in the areas of low and high pressure in the tubing (see DE-A-3642476).
  • This substantially linear increasing function is represented by a straight line having a pressure offset at the origin, called offset, and a gain (or slope of the straight line) which are each drawn from a map, depending at least on the engine speed.
  • motor vehicles are equipped with a receptacle, called a canister, containing means for absorbing fuel vapors.
  • This canister is connected to the tank by a recovery pipe, is provided with a vent putting the fuel tank in the open air and is connected to the intake circuit, preferably downstream of the butterfly valve, by a suction pipe. on which is mounted an electrically controlled canister purge valve, the flow of which is controlled by the computer.
  • the purge circuit thus produced allows, when the valve is open, and due to the vacuum prevailing downstream of the butterfly in the pipe, to suck in ambient air through the vent, through the canister, and to purge thus the canister of the fuel that it contains by mixing it with this ambient air so that it is sucked with it in the intake circuit.
  • the electrically operated purge valve is generally a solenoid valve controlled at constant frequency, and the control parameter of which is the opening duty cycle (RCO) which is variable, that is to say the opening time , for a constant period, corresponds to a variable fraction of this period, which corresponds to the length of the slot of the electric control current applied (see US-A-4467769).
  • RCO opening duty cycle
  • the opening cyclic ratio is defined by a map based mainly on the pressure in the intake manifold and engine speed.
  • mapping does not take into account the filling state of the canister, and is therefore deliberately limited to low flow rates to reduce the contribution of the canister.
  • the purge of the canister and the self-adaptation of the offset and gain terms occur simultaneously, at all speeds: we adopt, as the self-adaptation term, an idle offset when the engine is running at idle, and, without idling , an offset except idle at low pressures, where the influence of the offset is preponderant, and a gain at high pressure.
  • the purge state is taken into account by the self-adaptation by calculating a purge offset, when the purge is authorized. Indeed, as the flow rate of the canister depends little on the pressure in a large operating range of the engine, the purging of the canister is felt as an offset and not as a gain.
  • the self-adaptation does not ensure a continuous monitoring of the contribution of the canister, and, in the operating range at high pressure of tubing, it does not suitably modulate the gain.
  • the simultaneous purging and self-adaptation is particularly disadvantageous under certain engine operating conditions, at low loads, where the overabundant supply of fuel vapor from the canister vis-à-vis the engine requirement causes excessive drift.
  • the known embodiment presented above has the drawback that the absence of a difference between the gain under purge and the gain outside purge, and the course of the first order self-adaptation under purge lead to poor first order adaptation.
  • the known method of self-adaptation of richness and authorization of purging does not allow an obvious estimate of the injection time resulting from the application of the purge offset, since the injection time applied can be less than the time minimum below which the flow characteristic of an injector is no longer linear or reproducible.
  • the multiplicative enrichments apply to the purge offset, and the adaptation of the gain under purge is an aberration.
  • the problem underlying the invention is to remedy these drawbacks.
  • only the offset or the gain is adapted respectively during self-adaptation cycles executed only in the first range or respectively the second operating range of the motor.
  • the flow rate of the purge valve is not prohibited in the operating range of the engine which extends between the first and second ranges.
  • the purge is interrupted to allow the adjustment of the offset or gain, a certain number of times, and when this maximum possible number of cycles is carried out. , the purge is then re-authorized. To allow a new self-adaptation, it is necessary to have executed the maximum allowed number of self-adaptation of the other term (gain or offset).
  • the method consists in prohibiting the flow rate of the purge valve, in replacing the self-adaptation in offset with a cyclic self-adaptation in idle offset, which is interrupted as soon as the value the idle shift after a given cycle is sufficiently close to that obtained after the previous cycle, and then authorize the flow of the purge valve.
  • the idle offset self-adaptation can be repeated cyclically until a constant value of the idle offset is obtained.
  • the subject of the invention is also a device, intended for implementing the method specific to the invention, and as presented above, and which is characterized in that the computer comprises at least one programmed microprocessor and / or carried out so as to control the progress of this process.
  • FIG. 1 is schematically shown in 1, an injection engine, four-cylinder four-stroke, and spark ignition, equipped with an indirect fuel injection system of the multipoint type.
  • This installation comprises four injectors 2 each mounted in one respectively of the four branches 3 downstream of an intake manifold 4, and each opening into the cylinder head of the engine 1, at the level of the intake valve of a cylinder corresponding.
  • a throttle valve 5 for controlling the intake air flow is rotatably mounted in a throttle body 6 in the upstream part of the pipe 4, the throttle body 6 having a bypass pipe 7 on the throttle valve 5, and the passage section is regulated by a valve shown diagrammatically at 8 and controlled by a stepping motor 9.
  • the injectors 2 are supplied with fuel under a pressure defined by the regulator 10, itself supplied from the tank 11, closed by a tight plug, by means of the pump 12 on the supply line 13 on which is also fitted the filter 14. The remainder of the quantity of fuel diverted by the regulator 10 to the injectors 2 is returned to the tank 11 by the return line 15.
  • the fuel vapors forming in the tank 11 are collected by a canister 16, containing an absorbent charge of these vapors, for example activated carbon, and connected to the tank by the recovery pipe 17.
  • the canister 16 has a vent 18, by which it puts the reservoir 11 in the open air, and is connected to the intake manifold 4, downstream of the throttle valve 5 by a suction pipe 19 on which is mounted an electrically controlled valve 20, for purging the canister 16.
  • This valve 20 is a solenoid valve normally closed at rest and with opening controlled by RCO variable.
  • the R.C.O. variable of this valve 20 therefore the purge flow of the canister 16 of the fuel vapors it contains, as well as the position of the electric stepper motor 9 are controlled by electrical commands which are transmitted to them from the computer 21 by the conductors 22 and 23.
  • the duration of opening or injection of the injectors 2 is controlled by electrical commands applied by the computer 21 to the injectors 2 by the conductor 24.
  • injection duration variable RCO, stepping motor control
  • various sensors of engine operating parameters including an air temperature signal of intake 25, delivered by a temperature probe 26 placed in the air stream, an absolute pressure signal for tubing 27 delivered by a pressure probe 28 in tubing 4, a temperature signal 29 for engine cooling water 1, supplied by a sensor (not shown), and an engine rotation signal 30, making it possible to determine the engine speed, as well as the passages at TDC in the various cylinders for determining the instants of injection.
  • This signal 30 can be supplied by a sensor cooperating with a toothed wheel driven by the flywheel and having a singularity of detection of the transition to TDC of a reference cylinder.
  • the computer 21 also receives a signal 31 of the butterfly opening angle 5 supplied by an appropriate sensor, such as a potentiometer for copying the angular position of the butterfly 5, and mounted on the axis of rotation of the latter, and delivers at 33 a fuel consumption signal. Finally, the computer 21 receives at 32 a richness signal R delivered, in the form of electrical voltage, by an oxygen probe called the ⁇ probe, placed in the engine exhaust gases, of which it indicates the oxygen content. In operation of the engine in closed loop, the richness signal R is used by the computer 21 to center the operation of the engine on a richness equal to 1. For this, the computer 21 first calculates a basic injection duration , with reference to a network of curves stored in the computer 21 and such as that shown in FIG.
  • the computer 21 then increases or reduces the injection duration applied to the injectors 2 to obtain a richness signal R equal to 1. For this, the computer 21 calculates a richness coefficient KO2 by which it multiplies the basic injection time T inj B given by the formula (1).
  • the richness coefficient KO2 is chosen equal to 1. These zones correspond in particular to operation with a faulty ⁇ probe, or with an air temperature below an input threshold in a closed loop, for example in the event of a cold start of the engine, or when the open loop is imposed by the speed or the opening angle of the throttle, for example in deceleration or at full load, or if the engine speed N is higher than a given high threshold, for example 4500 rpm, and, in general, each time the target wealth differs from 1.
  • a given high threshold for example 4500 rpm
  • KO2 is a corrective multiplier coefficient of nominal value equal to 1.
  • FIG. 3 represents three characteristic operating ranges of the engine 1, defined by the engine speed N on the ordinate and by the pressure in the pipe P tub on the abscissa, in which it is possible to carry out the cyclic self-adaptation calculations for an operation engine idle in ranges 1 and 2, and idling in range 3.
  • Tracks 1 and 2 are operating ranges respectively at low and high tubing pressure, each defined between a lower threshold and an upper threshold of P tub, respectively P1 and P2 or P3 and P4, such as P1 ⁇ P2 ⁇ P3 ⁇ P4 , so that tracks 1 and 2 are not adjacent.
  • ranges 1 and 2 are defined between the same lower speed threshold N1, for example of 1200 rpm, and the same higher speed threshold N2, for example of 4000 rpm.
  • Range 1 is that in which the cyclic self-adaptation is only ensured on the offset D without idling, while in range 2, the self-adaptation is only ensured on the gain G.
  • range 1 it authorizes the self-adaptation of D out of idle for at most a maximum number of n1 cycles, for example equal to 2, thanks to a first counter which is initialized to this value when the computer is powered up and decremented by the value of one unit for each cycle performed.
  • the computer 21 authorizes the self-adaptation of G for at most a maximum number of n2 cycles, for example equal to 1, thanks to a second counter which is also initialized at this value when the power is turned on. calculator, and decremented by one at each cycle.
  • the computer 21 resets the two counters respectively to n1 and n2, and again authorizes self-adaptation cycles, if necessary, then prohibiting the purging.
  • the purging of the canister 16 by the purge valve 20 is not prohibited by the computer 21 unless the engine operating point is in range 1, and the first counter is not zero, or the engine operating point is in range 2 and the second counter is not zero.
  • the idling range 3 is limited by an upper threshold of engine speed N which is lower or, at most, equal to the lower threshold N1 of ranges 1 and 2.
  • range 3 can extend from on either side of the lower pressure threshold P1 of range 1, or always be less than P1.
  • This idle range corresponds to a low speed and a throttle angle weak or zero.
  • the self-adaptation is carried out by substituting for the term offset D without idling, an offset in idling DR.
  • the computer 21 prohibits the flow of the purge valve 20, and begins the cyclic self-adaptation of DR, chosen independent of the engine speed, and interrupts this adaptation as soon as the value of DR after a cycle given is equal to that obtained after the previous cycle.
  • the computer 21 then authorizes the flow rate from the purge valve 20.
  • the DR self-adaptation can be authorized for at most a maximum number of n3 cycles, using a third counter initialized at each power-up and then at each entry in idle mode (entry in range 3).
  • the method consists in cyclically repeating the self-adaptation of DR until a constant value is obtained which is taken into account for the calculation of the injection duration.
  • the computer 21 After execution of the n3 cycles in the first case, or obtaining a constant value of DR in the second case, the computer 21 again authorizes the purge.
  • the method of self-adaptation of the richness and authorization of the purging of the canister purge circuit described above thus ensures a dissociation between the self-adaptation and the purge, which overcomes the drawbacks of the methods of the prior art , and allows a good first order adaptation, and in particular a good modulation of the gain in range 2.
  • the computer 21 which is in fact a central computing and control unit, with in particular the circuits of calculation, memories, counters, registers and other regulation and control circuits, necessary and of known structure, comprises at least one microprocessor or microcontroller programmed and / or produced so as to control the progress of this process.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
  • Supplying Secondary Fuel Or The Like To Fuel, Air Or Fuel-Air Mixtures (AREA)

Description

L'invention concerne un procédé d'autoadaptation de la richesse et d'autorisation de la purge d'un circuit de purge comprenant un canister, pour un moteur à combustion interne, du type à allumage commandé, équipé d'une installation d'alimentation en combustible par injection, et de ce fait dénommé moteur à injection dans la suite de la présente description, et de préférence, mais non exclusivement, à cycle moteur à quatre temps.The invention relates to a method of self-adaptation of the richness and authorization of the purge of a purge circuit comprising a canister, for an internal combustion engine, of the spark-ignition type, equipped with a supply installation. in injection fuel, and therefore referred to as an injection engine in the remainder of this description, and preferably, but not exclusively, with a four-stroke engine cycle.

On sait que l'installation d'alimentation en combustible d'un tel moteur à injection comprend une tubulure d'admission d'air au moteur, sur l'amont de laquelle un obturateur de commande du débit d'air, le plus souvent en forme de disque, appelé papillon, est monté rotatif dans un corps. L'installation d'injection comprend au moins un injecteur délivrant du combustible dans la tubulure d'admission. L'injecteur ou chaque injecteur est alimenté en combustible à une pression donnée par un régulateur, qui dérive vers l'injecteur une partie du combustible qu'il reçoit du réservoir par une pompe, et qui retourne au réservoir la quantité de combustible en excédent par rapport à celle injectée, laquelle est fonction de la durée d'ouverture de l'injecteur, appelé durée d'injection, et déterminée par un calculateur relié à des capteurs de paramètres de fonctionnement du moteur. De ces capteurs, le calculateur reçoit généralement des signaux représentatifs de la température d'eau ou du liquide de refroidissement du moteur, de la température d'air dans la tubulure d'admission, de l'angle d'ouverture du papillon, et surtout il reçoit des signaux de rotation du moteur, fournis par exemple par un capteur coopérant avec une roue dentée solidaire du volant moteur, et présentant une singularité, par exemple une dent manquante, pour détecter le point mort haut (P.M.H.) d'un cylindre de référence, permettant au calculateur de déterminer les phases ou temps d'injection dans les différents cylindres, le régime du moteur étant calculé à partir du signal modulé par le défilement des dents. Le calculateur peut également recevoir un signal de pression mesurée directement dans la tubulure d'admission, ou peut calculer ce signal de pression à partir de deux mesures choisies dans le groupe comprenant l'angle d'ouverture du papillon, le débit d'air et le régime moteur.It is known that the fuel supply installation of such an injection engine comprises an air intake manifold to the engine, on the upstream of which a shutter for controlling the air flow, most often in disc shape, called butterfly, is rotatably mounted in a body. The injection installation comprises at least one injector delivering fuel into the intake manifold. The injector or each injector is supplied with fuel at a pressure given by a regulator, which drifts towards the injector a part of the fuel which it receives from the tank by a pump, and which returns to the tank the quantity of excess fuel by compared to that injected, which is a function of the duration of opening of the injector, called injection duration, and determined by a computer connected to sensors for operating parameters of the engine. From these sensors, the computer generally receives signals representative of the engine water or coolant temperature, the air temperature in the intake manifold, the throttle opening angle, and above all it receives engine rotation signals, supplied for example by a sensor cooperating with a toothed wheel integral with the flywheel, and having a singularity, for example a missing tooth, for detecting dead center top (TDC) of a reference cylinder, allowing the computer to determine the injection phases or times in the different cylinders, the engine speed being calculated from the signal modulated by the movement of the teeth. The computer can also receive a pressure signal measured directly in the intake manifold, or can calculate this pressure signal from two measurements chosen from the group comprising the throttle opening angle, the air flow and engine speed.

Ce calculateur, qui détermine l'instant et la durée d'injection de chaque injecteur, est en général simultanément un calculateur de contrôle moteur, remplissant d'autres fonctions de commande et de contrôle, et déterminant notamment les instants d'allumage des bougies des cylindres du moteur.This computer, which determines the instant and duration of injection of each injector, is generally simultaneously an engine control computer, fulfilling other command and control functions, and determining in particular the instants of ignition of the spark plugs of the engine cylinders.

Afin de respecter les normes d'anti-pollution et d'obtenir un bon fonctionnement du pot catalytique, en terme d'émission de gaz polluants, il est connu de relier au calculateur une sonde d'oxygène, dite sonde λ, disposée dans les gaz d'échappement du moteur et sensible à la présence d'oxygène dans ces gaz d'échappement. Le signal de richesse fourni par la sonde λ est utilisé pour réguler le fonctionnement du moteur autour d'une valeur de richesse égale à 1, correspondant au mélange stoechiométrique. A partir d'une durée d'injection de base, calculée essentiellement en fonction du régime moteur et de la pression dans la tubulure, il est connu d'assurer une régulation à partir de la sonde d'oxygène en corrigeant cette durée d'injection de base en tenant compte d'un coefficient de richesse KO2, déterminé, notamment par application de transitions de valeur, en fonction du signal de richesse de la sonde d'oxygène dans les zones de fonctionnement du moteur en boucle fermée, et fixé égal à une valeur nominale dans les cas de fonctionnement du moteur en boucle ouverte, par exemple en fonctionnement à basse température (après démarrage du moteur à froid), ou en décélération, ou à pleine charge, et enfin si le régime moteur est supérieur à un seuil élevé donné.In order to comply with anti-pollution standards and to obtain proper operation of the catalytic converter, in terms of emission of polluting gases, it is known to connect to the computer an oxygen probe, called a λ probe, placed in the engine exhaust gases and sensitive to the presence of oxygen in these exhaust gases. The richness signal provided by the λ probe is used to regulate the operation of the engine around a richness value equal to 1, corresponding to the stoichiometric mixture. From a basic injection duration, calculated essentially as a function of the engine speed and of the pressure in the manifold, it is known to provide regulation from the oxygen sensor by correcting this injection duration basic taking into account a richness coefficient KO2, determined, in particular by applying value transitions, as a function of the richness signal of the oxygen sensor in the engine operating zones in closed loop, and fixed equal to a nominal value in the case of open-loop motor operation, for example in low temperature operation (after starting the engine cold), or in deceleration, or at full load, and finally if the engine speed is above a given high threshold.

Si la correction de la durée d'injection de base en fonction du coefficient de richesse KO2 s'effectue par multiplication par ce coefficient KO2, alors la valeur nominale de ce dernier est égale à 1.If the correction of the basic injection duration as a function of the richness coefficient KO2 is carried out by multiplication by this coefficient KO2, then the nominal value of the latter is equal to 1.

La prise en compte du coefficient de richesse KO2 par le calculateur permet d'augmenter ou de réduire la durée d'injection de base, pour centrer le fonctionnement du moteur sur une richesse égale à 1. De plus, il est connu d'exprimer, pour un régime moteur donné, la durée d'injection de base comme une fonction sensiblement linéaire croissante, dans la plage de fonctionnement utile du moteur, de la pression absolue dans la tubulure d'admission, représentant le couple du moteur, c'est-à-dire la charge du moteur, et en négligeant des coefficients correcteurs issus de cartographies, par exemple en fonction du régime moteur, de la pression dans la tubulure ou de l'angle d'ouverture du papillon, pour traduire l'inflexion de la droite en une courbe en S, dans les zones de pression faible et élevée dans la tubulure (voir DE-A-3642476).Taking into account the richness coefficient KO2 by the computer makes it possible to increase or reduce the basic injection time, to center the operation of the engine on a richness equal to 1. Furthermore, it is known to express, for a given engine speed, the basic injection duration as a substantially linear function increasing, in the useful operating range of the engine, of the absolute pressure in the intake manifold, representing the engine torque, i.e. the engine load, and neglecting correction coefficients from maps, for example as a function of engine speed, pressure in the manifold or the throttle opening angle, to reflect the inflection of the straight in an S curve, in the areas of low and high pressure in the tubing (see DE-A-3642476).

Cette fonction sensiblement linéaire croissante est représentée par une droite ayant un décalage de pression à l'origine, appelé offset, et un gain (ou pente de la droite) qui sont chacun tirés d'une cartographie, en fonction au moins du régime moteur.This substantially linear increasing function is represented by a straight line having a pressure offset at the origin, called offset, and a gain (or slope of the straight line) which are each drawn from a map, depending at least on the engine speed.

Il est également connu d'utiliser le calculateur pour corriger dans un second temps, par une auto-adaptation cyclique, la durée d'injection de base tirée de la droite et corrigée dans un premier temps par multiplication avec le coefficient de richesse KO2. Cette auto-adaptation cyclique a pour but d'assurer que le coefficient de richesse KO2 reste voisin de 1, par correction de toute dérive de ce coefficient de richesse KO2. A cet effet, il est connu d'effectuer une auto-adaptation dite du "premier ordre", en modifiant les termes d'adaptation que sont le décalage et le gain dans respectivement une première et une seconde plages de fonctionnement du moteur, respectivement à basse et à haute pression dans la tubulure d'admission.It is also known to use the computer to correct in a second step, by a cyclic self-adaptation, the basic injection time taken from the line and corrected in a first step by multiplication with the richness coefficient KO2. The aim of this cyclic self-adaptation is to ensure that the richness coefficient KO2 remains close to 1, by correcting any drift of this richness coefficient KO2. To this end, it is known to perform a so-called "first order" self-adaptation, by modifying the adaptation terms that are the offset and the gain in first and second engine operating ranges, respectively at low and high pressure in the intake manifold, respectively.

Pour satisfaire aux normes d'anti-pollution relatives aux émissions de vapeurs de combustible, moteur à l'arrêt ou en fonctionnement, les véhicules automobiles sont équipés d'un réceptacle, appelé canister, contenant des moyens d'absorption des vapeurs de combustible. Ce canister est relié au réservoir par une conduite de récupération, est muni d'un évent mettant le réservoir de combustible à l'air libre et est relié au circuit d'admission, de préférence en aval du papillon, par une conduite d'aspiration sur laquelle est montée une vanne de purge du canister à commande électrique, dont le débit est piloté par le calculateur. Le circuit de purge ainsi réalisé permet, lorsque la vanne est ouverte, et en raison de la dépression régnant en aval du papillon dans la tubulure, d'aspirer de l'air ambiant par l'évent, au travers du canister, et de purger ainsi le canister du combustible qu'il contient en le mélangeant à cet air ambiant pour qu'il soit aspiré avec lui dans le circuit d'admission. La vanne de purge à commande électrique est en général une électrovanne commandée à fréquence constante, et dont le paramètre de commande est le rapport cyclique d'ouverture (R.C.O.) qui est variable, c'est-à-dire que la durée d'ouverture, pour une période constante, correspond à une fraction variable de cette période, qui correspond à la longueur du créneau du courant électrique de commande appliqué (voir US-A-4467769).To meet the anti-pollution standards relating to fuel vapor emissions, with the engine stopped or in operation, motor vehicles are equipped with a receptacle, called a canister, containing means for absorbing fuel vapors. This canister is connected to the tank by a recovery pipe, is provided with a vent putting the fuel tank in the open air and is connected to the intake circuit, preferably downstream of the butterfly valve, by a suction pipe. on which is mounted an electrically controlled canister purge valve, the flow of which is controlled by the computer. The purge circuit thus produced allows, when the valve is open, and due to the vacuum prevailing downstream of the butterfly in the pipe, to suck in ambient air through the vent, through the canister, and to purge thus the canister of the fuel that it contains by mixing it with this ambient air so that it is sucked with it in the intake circuit. The electrically operated purge valve is generally a solenoid valve controlled at constant frequency, and the control parameter of which is the opening duty cycle (RCO) which is variable, that is to say the opening time , for a constant period, corresponds to a variable fraction of this period, which corresponds to the length of the slot of the electric control current applied (see US-A-4467769).

Afin de purger le canister de manière à, simultanément, respecter les normes d'anti-pollution relatives aux émissions de vapeurs d'hydrocarbures, et obtenir un fonctionnement sans à-coups du moteur pour assurer le confort des occupants du véhicule (qualité de roulage), tout en respectant les normes d'anti-pollution relatives aux émissions d'imbrûlés et en préservant un bon fonctionnement du pot catalytique, le rapport cyclique d'ouverture est défini par une cartographie en fonction principalement de la pression dans la tubulure d'admission et du régime moteur.In order to purge the canister so as to simultaneously comply with the anti-pollution standards relating to emissions of hydrocarbon vapors, and obtain smooth operation of the engine to ensure the comfort of the occupants of the vehicle (driving quality ), while respecting the anti-pollution standards relating to unburnt emissions and preserving the proper functioning of the catalytic converter, the opening cyclic ratio is defined by a map based mainly on the pressure in the intake manifold and engine speed.

Mais cette cartographie ne tient pas compte de l'état de remplissage du canister, et est donc volontairement limitée à de faibles débits pour réduire la contribution du canister.However, this mapping does not take into account the filling state of the canister, and is therefore deliberately limited to low flow rates to reduce the contribution of the canister.

De plus, la purge du canister et l'autoadaptation des termes de décalage et de gain interviennent simultanément, à tous les régimes : on adopte, comme terme d'autoadaptation, un décalage de ralenti lorsque le moteur fonctionne au ralenti, et, hors ralenti, un décalage hors ralenti aux basses pressions, où l'influence du décalage est prépondérante, et un gain à haute pression. En outre, l'état de purge est pris en compte par l'autoadaptation par le calcul d'un décalage de purge, lorsque la purge est autorisée. En effet, comme le débit du canister dépend peu de la pression dans une grande plage de fonctionnement du moteur, la purge du canister est ressentie comme un décalage et non comme un gain.In addition, the purge of the canister and the self-adaptation of the offset and gain terms occur simultaneously, at all speeds: we adopt, as the self-adaptation term, an idle offset when the engine is running at idle, and, without idling , an offset except idle at low pressures, where the influence of the offset is preponderant, and a gain at high pressure. In addition, the purge state is taken into account by the self-adaptation by calculating a purge offset, when the purge is authorized. Indeed, as the flow rate of the canister depends little on the pressure in a large operating range of the engine, the purging of the canister is felt as an offset and not as a gain.

En conséquence, l'autoadaptation n'assure pas un suivi continu de la contribution du canister, et, dans la plage de fonctionnement à haute pression de tubulure, elle ne module pas convenablement le gain.Consequently, the self-adaptation does not ensure a continuous monitoring of the contribution of the canister, and, in the operating range at high pressure of tubing, it does not suitably modulate the gain.

La simultanéité de la purge et de l'autoadaptation est particulièrement désavantageuse dans certaines conditions de fonctionnement du moteur, aux faibles charges, où l'apport surabondant de vapeur de combustible provenant du canister vis-à-vis du besoin du moteur provoque une dérive excessive du coefficient de richesse KO2.The simultaneous purging and self-adaptation is particularly disadvantageous under certain engine operating conditions, at low loads, where the overabundant supply of fuel vapor from the canister vis-à-vis the engine requirement causes excessive drift. the richness coefficient KO2.

Dans ces conditions de fonctionnement, en effet, dans un environnement échauffé par le moteur en fonctionnement, le retour au réservoir de combustible chaud provenant du régulateur de pression d'alimentation des injecteurs et le brassage de combustible qui en résulte, ainsi que du fonctionnement de la pompe, sont les causes d'une intense production de vapeurs de combustible dans le réservoir.In these operating conditions, in fact, in an environment heated by the engine in operation, the return to the hot fuel tank coming from the injector supply pressure regulator and the resulting fuel mixing, as well as the operation of the pump, are the causes of an intense production of fuel vapors in the tank.

En conséquence, la réalisation connue présentée ci-dessus a pour inconvénient que l'absence de différence entre le gain sous purge et le gain hors purge, et le déroulement de l'autoadaptation du premier ordre sous purge entraînent une mauvaise adaptation du premier ordre.Consequently, the known embodiment presented above has the drawback that the absence of a difference between the gain under purge and the gain outside purge, and the course of the first order self-adaptation under purge lead to poor first order adaptation.

Un mauvais suivi de l'évolution de la purge résulte de plages d'adaptation sous purge dans des zones de fonctionnement moteur limitées, qui sont la plage d'adaptation du décalage sous purge et la plage d'adaptation du gain. En outre, le procédé connu n'effectue pas de différenciation des vitesses d'adaptation du premier ordre et de la purge, alors que la dérive du premier ordre et l'évolution de la purge sont deux phénomènes très différents.Poor monitoring of the evolution of the purge results from adaptation ranges under purge in limited engine operating zones, which are the adaptation range of the offset under purge and the gain adaptation range. In addition, the known method does not differentiate between the first order adaptation rates and the purge, while the first order drift and the evolution of the purge are two very different phenomena.

Le procédé connu d'autoadaptation de richesse et d'autorisation de purge ne permet pas d'estimer de manière évidente le temps d'injection résultant de l'application du décalage de purge, puisque le temps d'injection appliqué peut être inférieur au temps minimum au-dessous duquel la caractéristique de débit d'un injecteur n'est plus linéaire ni reproductible. Comme la purge est ressentie comme un décalage, et non comme un gain, les enrichissements multiplicatifs s'appliquent sur le décalage de purge, et l'adaptation du gain sous purge est une aberration.The known method of self-adaptation of richness and authorization of purging does not allow an obvious estimate of the injection time resulting from the application of the purge offset, since the injection time applied can be less than the time minimum below which the flow characteristic of an injector is no longer linear or reproducible. As the purge is felt as an offset, and not as a gain, the multiplicative enrichments apply to the purge offset, and the adaptation of the gain under purge is an aberration.

Le problème à la base de l'invention est de remédier à ces inconvénients.The problem underlying the invention is to remedy these drawbacks.

A cet effet, l'invention propose un procédé d'autoadaptation de la richesse et d'autorisation de purge d'un circuit de purge d'un moteur à injection, du type connu pour lequel le circuit de purge comprend un canister collectant des vapeurs de combustible provenant d'un réservoir, et relié à une tubulure d'admission du moteur munie d'un obturateur ou papillon de commande du débit d'air, par une vanne de purge du canister à commande électrique, dont le débit est piloté par un calculateur relié à des capteurs de paramètres de fonctionnement du moteur dont il reçoit au moins des signaux de rotation du moteur et des signaux permettant de connaître la pression dans la tubulure d'admission, ainsi qu'à une sonde d'oxygène dans les gaz d'échappement du moteur, ledit calculateur calculant une durée d'injection, transmise à au moins un injecteur, et obtenue à partir d'une durée d'injection de base exprimée, pour un régime moteur donné, comme une fonction sensiblement linéaire croissante de la pression dans la tubulure, avec un décalage (offset) à l'origine et un gain qui sont tirés de cartographies en fonction au moins du régime moteur, et corrigée en prenant en compte un coefficient de richesse (KO2) déterminé en fonction du signal de richesse de la sonde d'oxygène dans les zones de fonctionnement du moteur en boucle fermée et fixé égal à une valeur nominale dans les zones de fonctionnement du moteur en boucle ouverte, pour assurer le centrage du fonctionnement du moteur sur une richesse égale à 1, le décalage et le gain faisant de plus l'objet d'une autoadaptation cyclique pour assurer que le coefficient de richesse (KO2) reste voisin de sa valeur nominale, par correction de toute dérive de ce coefficient de richesse (KO2), dans au moins une première plage de fonctionnement du moteur, à basse pression de tubulure, par modification d'au moins le décalage, et dans au moins une seconde plage de fonctionnement du moteur, à haute pression de tubulure, par modification d'au moins le gain, et se caractérise en ce qu'il consiste :

  • à interdire l'autoadaptation simultanément au débit de la vanne de purge,
  • à chaque entrée en phase d'autoadaptation, à autoriser celle-ci pendant au plus un nombre maximum de n1 cycles, dans la première plage de fonctionnement, et pendant au plus un nombre maximum de n2 cycles dans la seconde plage de fonctionnement,
  • à n'autoriser le débit de la vanne de purge qu'après l'exécution dudit nombre maximum de respectivement n1 ou n2 cycles d'autoadaptation, et
  • à ne permettre une nouvelle autoadaptation en décalage ou en gain qu'après exécution de tous les cycles d'autoadaptation permis en gain et en décalage.
To this end, the invention provides a method of self-adaptation of the richness and authorization to purge a purge circuit of an injection engine, of the known type for which the purge circuit comprises a canister collecting vapors. of fuel coming from a tank, and connected to an engine intake manifold fitted with a shutter or butterfly for controlling the air flow, by an electrically controlled canister purge valve, the flow of which is controlled by a computer connected to engine operating parameter sensors from which it receives at least engine rotation signals and signals allowing to know the pressure in the intake manifold, as well as to an oxygen sensor in the engine exhaust gases, said computer calculating an injection duration, transmitted to at least one injector, and obtained from of a base injection duration expressed, for a given engine speed, as a substantially linear increasing function of the pressure in the manifold, with an offset (offset) at the origin and a gain which are taken from maps as a function at least engine speed, and corrected by taking into account a richness coefficient (KO2) determined as a function of the richness signal of the oxygen sensor in the engine operating zones in closed loop and fixed equal to a nominal value in the motor operating zones in open loop, to ensure the centering of the motor operation on a richness equal to 1, the offset and the gain being the subject of a cyclic self-adaptation for assu rer that the richness coefficient (KO2) remains close to its nominal value, by correction of any drift of this richness coefficient (KO2), in at least a first operating range of the engine, at low manifold pressure, by modification of '' at least the offset, and in at least a second operating range of the motor, at high manifold pressure, by modification of at least the gain, and is characterized in that it consists:
  • to prohibit self-adaptation simultaneously with the flow rate of the purge valve,
  • at each entry into the self-adaptation phase, to authorize it for at most a maximum number of n1 cycles, in the first operating range, and for at most a maximum number of n2 cycles in the second operating range,
  • to authorize the flow rate of the purge valve only after the execution of said maximum number of respectively n1 or n2 self-adaptation cycles, and
  • not to allow a new self-adaptation in offset or gain only after execution of all the self-adaptation cycles allowed in gain and offset.

De préférence, on adapte uniquement le décalage ou respectivement le gain lors de cycles d'autoadaptation exécutés uniquement dans la première plage ou respectivement la seconde plage de fonctionnement du moteur.Preferably, only the offset or the gain is adapted respectively during self-adaptation cycles executed only in the first range or respectively the second operating range of the motor.

De plus, quelles que soient les conditions d'autoadaptation, le débit de la vanne de purge n'est pas interdit dans la plage de fonctionnement du moteur qui s'étend entre les première et seconde plages.In addition, whatever the self-adaptation conditions, the flow rate of the purge valve is not prohibited in the operating range of the engine which extends between the first and second ranges.

Donc, en fonctionnement du moteur hors ralenti, à chaque entrée dans les conditions d'adaptation, la purge est interrompue pour permettre l'adaptation du décalage ou du gain, un certain nombre de fois, et lorsque ce nombre maximum possible de cycles est effectué, la purge est alors réautorisée. Pour permettre une nouvelle autoadaptation, il faut avoir exécuté le nombre maximum permis d'autoadaptation de l'autre terme (gain ou décalage).Therefore, when the engine is running without idling, each time the adaptation conditions are entered, the purge is interrupted to allow the adjustment of the offset or gain, a certain number of times, and when this maximum possible number of cycles is carried out. , the purge is then re-authorized. To allow a new self-adaptation, it is necessary to have executed the maximum allowed number of self-adaptation of the other term (gain or offset).

A l'entrée du moteur dans une plage de fonctionnement au ralenti, le procédé consiste à interdire le débit de la vanne de purge, à substituer à l'autoadaptation en décalage une autoadaptation cyclique en décalage de ralenti, qui est interrompue dès que la valeur du décalage de ralenti après un cycle donné est suffisamment voisine de celle obtenue après le cycle précédent, et à autoriser ensuite le débit de la vanne de purge.At the entry of the engine into an idling operating range, the method consists in prohibiting the flow rate of the purge valve, in replacing the self-adaptation in offset with a cyclic self-adaptation in idle offset, which is interrupted as soon as the value the idle shift after a given cycle is sufficiently close to that obtained after the previous cycle, and then authorize the flow of the purge valve.

En outre, l'autoadaptation en décalage de ralenti peut être répétée cycliquement jusqu'à l'obtention d'une valeur constante du décalage de ralenti.In addition, the idle offset self-adaptation can be repeated cyclically until a constant value of the idle offset is obtained.

L'invention a également pour objet un dispositif, destiné à la mise en oeuvre du procédé propre à l'invention, et tel que présenté ci-dessus, et qui se caractérise en ce que le calculateur comprend au moins un microprocesseur programmé et/ou réalisé de manière à commander le déroulement de ce procédé.The subject of the invention is also a device, intended for implementing the method specific to the invention, and as presented above, and which is characterized in that the computer comprises at least one programmed microprocessor and / or carried out so as to control the progress of this process.

D'autres caractéristiques et avantages de l'invention découleront de la description donnée ci-dessous, à titre non limitatif, d'un exemple de réalisation, décrit en référence aux dessins annexés sur lesquels :

  • la figure 1 représente schématiquement un moteur à injection, avec un circuit de purge de canister, et un calculateur de commande,
  • la figure 2 représente, pour un régime moteur donné, une courbe exprimant la durée d'injection en fonction de la pression absolue dans la tubulure d'admission, et
  • la figure 3 est un graphique représentant, en fonction du régime moteur et de la pression dans la tubulure, différentes zones de fonctionnement du moteur, dont les zones d'adaptation en décalage et en gain, et de fonctionnement au ralenti.
Other characteristics and advantages of the invention Will follow from the description given below, without limitation, of an exemplary embodiment, described with reference to the accompanying drawings in which:
  • FIG. 1 schematically represents an injection engine, with a canister purge circuit, and a control computer,
  • FIG. 2 represents, for a given engine speed, a curve expressing the duration of injection as a function of the absolute pressure in the intake manifold, and
  • FIG. 3 is a graph representing, as a function of the engine speed and of the pressure in the manifold, different areas of engine operation, including the offset and gain adaptation areas, and of idle operation.

Sur la figure 1 est schématiquement représenté en 1, un moteur à injection, à quatre cylindres-quatre temps, et allumage commandé, équipé d'une installation d'injection indirecte de carburant de type multipoint. Cette installation comprend quatre injecteurs 2 montés chacun dans l'une respectivement des quatre branches 3 en aval d'une tubulure d'admission 4, et débouchant chacune dans la culasse du moteur 1, au niveau de la soupape d'admission d'un cylindre correspondant. Un papillon 5 de commande du débit d'air d'admission est monté rotatif dans un corps de papillon 6 dans la partie amont de la tubulure 4, le corps de papillon 6 présentant une conduite 7 en dérivation sur le papillon 5, et dont la section de passage est régulée par une vanne schématisée en 8 et commandée par un moteur pas à pas 9.In Figure 1 is schematically shown in 1, an injection engine, four-cylinder four-stroke, and spark ignition, equipped with an indirect fuel injection system of the multipoint type. This installation comprises four injectors 2 each mounted in one respectively of the four branches 3 downstream of an intake manifold 4, and each opening into the cylinder head of the engine 1, at the level of the intake valve of a cylinder corresponding. A throttle valve 5 for controlling the intake air flow is rotatably mounted in a throttle body 6 in the upstream part of the pipe 4, the throttle body 6 having a bypass pipe 7 on the throttle valve 5, and the passage section is regulated by a valve shown diagrammatically at 8 and controlled by a stepping motor 9.

Les injecteurs 2 sont alimentés en carburant sous une pression définie par le régulateur 10, lui-même alimenté à partir du réservoir 11, fermé par un bouchon étanche, par l'intermédiaire de la pompe 12 sur la canalisation d'alimentation 13 sur laquelle est également monté le filtre 14. Le complément de la quantité de carburant dérivée par le régulateur 10 vers les injecteurs 2 est renvoyé au réservoir 11 par la canalisation de retour 15.The injectors 2 are supplied with fuel under a pressure defined by the regulator 10, itself supplied from the tank 11, closed by a tight plug, by means of the pump 12 on the supply line 13 on which is also fitted the filter 14. The remainder of the quantity of fuel diverted by the regulator 10 to the injectors 2 is returned to the tank 11 by the return line 15.

Les vapeurs de carburant se formant dans le réservoir 11 sont collectées par un canister 16, contenant une charge absorbante de ces vapeurs, par exemple du charbon actif, et relié au réservoir par la conduite de récupération 17. Le canister 16 présente un évent 18, par lequel il met à l'air libre le réservoir 11, et est raccordé à la tubulure d'admission 4, en aval du papillon d'étranglement 5 par une conduite d'aspiration 19 sur laquelle est montée une vanne 20 à commande électrique, pour la purge du canister 16. Cette vanne 20 est une électrovanne normalement fermée au repos et à ouverture commandée par R.C.O. variable.The fuel vapors forming in the tank 11 are collected by a canister 16, containing an absorbent charge of these vapors, for example activated carbon, and connected to the tank by the recovery pipe 17. The canister 16 has a vent 18, by which it puts the reservoir 11 in the open air, and is connected to the intake manifold 4, downstream of the throttle valve 5 by a suction pipe 19 on which is mounted an electrically controlled valve 20, for purging the canister 16. This valve 20 is a solenoid valve normally closed at rest and with opening controlled by RCO variable.

Le R.C.O. variable de cette vanne 20, donc le débit de purge du canister 16 des vapeurs de carburant qu'il contient, ainsi que la position du moteur électrique pas à pas 9 sont pilotés par des ordres électriques qui leur sont transmis du calculateur 21 par les conducteurs 22 et 23. De même, la durée d'ouverture ou d'injection des injecteurs 2, fonction de la quantité de carburant injectée par chaque injecteur 2 dans le cylindre correspondant, (puisque la différence de pression appliquée aux injecteurs 2 est constante et fixée par le régulateur 10), est pilotée par des ordres électriques appliqués par le calculateur 21 aux injecteurs 2 par le conducteur 24.The R.C.O. variable of this valve 20, therefore the purge flow of the canister 16 of the fuel vapors it contains, as well as the position of the electric stepper motor 9 are controlled by electrical commands which are transmitted to them from the computer 21 by the conductors 22 and 23. Likewise, the duration of opening or injection of the injectors 2, depending on the amount of fuel injected by each injector 2 into the corresponding cylinder, (since the pressure difference applied to the injectors 2 is constant and fixed by the regulator 10), is controlled by electrical commands applied by the computer 21 to the injectors 2 by the conductor 24.

Ces ordres électriques (durée d'injection, R.C.O. variable, commande du moteur pas à pas) sont élaborés par le calculateur 21 à partir de signaux reçus de différents capteurs de paramètres de fonctionnement du moteur, dont un signal de température d'air d'admission 25, délivré par une sonde de température 26 placée dans la veine d'air, un signal de pression absolue de tubulure 27 délivré par une sonde de pression 28 dans la tubulure 4, un signal de température 29 d'eau de refroidissement du moteur 1, fourni par un capteur non représenté, et un signal 30 de rotation du moteur, permettant de déterminer le régime du moteur, ainsi que les passages au P.M.H. dans les différents cylindres pour la détermination des instants d'injection. Ce signal 30 peut être fourni par un capteur coopérant avec une roue dentée entraînée par le volant moteur et présentant une singularité de détection du passage au P.M.H. d'un cylindre de référence. Le calculateur 21 reçoit également un signal 31 d'angle d'ouverture du papillon 5 fourni par un capteur approprié, tel qu'un potentiomètre de recopie de la position angulaire du papillon 5, et monté sur l'axe de rotation de ce dernier, et délivre en 33 un signal de consommation de combustible. Enfin, le calculateur 21 reçoit en 32 un signal de richesse R délivré, sous forme de tension électrique, par une sonde d'oxygène dite sonde λ, disposée dans les gaz d'échappement du moteur, dont elle indique la teneur en oxygène. En fonctionnement du moteur en boucle fermée, le signal de richesse R est utilisé par le calculateur 21 pour centrer le fonctionnement du moteur sur une richesse égale à 1. Pour cela, le calculateur 21 calcule tout d'abord une durée d'injection de base, en se référant à un réseau de courbes mémorisées dans le calculateur 21 et telles que celle représentée sur la figure 2, qui donne pour un régime moteur constant donné, la durée d'injection de base T inj B en fonction de la pression absolue P tub dans la tubulure 4, cette courbe étant, sur la majeure partie de la plage de fonctionnement utile du moteur, assimilable à une fonction linéaire croissante définie par un décalage de pression à l'origine D et par un gain G correspondant à la pente de la droite représentative de cette fonction. D et G sont chacun tirés d'une cartographie en fonction notamment du régime moteur N (fonctions f(N) et g(N)). Dans les zones à haute et basse pressions, la courbe présente des parties arrondies en S obtenues à partir de la droite après correction multiplicative par un coefficient cartographique K carto, fonction notamment du régime moteur N, et de la pression P tub ou de l'angle d'ouverture du papillon 5 (fonction h (N, P)).These electrical orders (injection duration, variable RCO, stepping motor control) are produced by the computer 21 from signals received from various sensors of engine operating parameters, including an air temperature signal of intake 25, delivered by a temperature probe 26 placed in the air stream, an absolute pressure signal for tubing 27 delivered by a pressure probe 28 in tubing 4, a temperature signal 29 for engine cooling water 1, supplied by a sensor (not shown), and an engine rotation signal 30, making it possible to determine the engine speed, as well as the passages at TDC in the various cylinders for determining the instants of injection. This signal 30 can be supplied by a sensor cooperating with a toothed wheel driven by the flywheel and having a singularity of detection of the transition to TDC of a reference cylinder. The computer 21 also receives a signal 31 of the butterfly opening angle 5 supplied by an appropriate sensor, such as a potentiometer for copying the angular position of the butterfly 5, and mounted on the axis of rotation of the latter, and delivers at 33 a fuel consumption signal. Finally, the computer 21 receives at 32 a richness signal R delivered, in the form of electrical voltage, by an oxygen probe called the λ probe, placed in the engine exhaust gases, of which it indicates the oxygen content. In operation of the engine in closed loop, the richness signal R is used by the computer 21 to center the operation of the engine on a richness equal to 1. For this, the computer 21 first calculates a basic injection duration , with reference to a network of curves stored in the computer 21 and such as that shown in FIG. 2, which gives, for a given constant engine speed, the basic injection time T inj B as a function of the absolute pressure P tub in the manifold 4, this curve being, over most of the useful operating range of the engine, comparable to an increasing linear function defined by a pressure offset at the origin D and by a gain G corresponding to the slope of the line representative of this function. D and G are each drawn from a map depending in particular on the engine speed N (functions f (N) and g (N)). In the high and low pressure zones, the curve has rounded parts in S obtained from the right after multiplicative correction by a cartographic coefficient K carto, function in particular of the engine speed N, and of the pressure P tub or of the butterfly opening angle 5 (function h (N, P)).

Donc, pour un régime N et une pression d'admission P tub donnés, la durée d'injection de base est donnée par la formule (1) : (1)   T inj B = (P tub - D) x G x K carto

Figure imgb0001
L'application de cette durée d'injection aux injecteurs conduit à un signal de richesse R de la sonde λ en général différent de 1. Le calculateur 21 augmente ou réduit alors la durée d'injection appliquée aux injecteurs 2 pour obtenir un signal de richesse R égal à 1. Pour cela, le calculateur 21 calcule un coefficient de richesse KO2 par lequel il multiplie la durée d'injection de base T inj B donnée par la formule (1).So, for a given speed N and a given intake pressure P tub, the basic injection duration is given by the formula (1): (1) T inj B = (P tub - D) x G x K carto
Figure imgb0001
 The application of this injection duration to the injectors leads to a richness signal R of the probe λ generally different from 1. The computer 21 then increases or reduces the injection duration applied to the injectors 2 to obtain a richness signal R equal to 1. For this, the computer 21 calculates a richness coefficient KO2 by which it multiplies the basic injection time T inj B given by the formula (1).

Dans les zones de fonctionnement du moteur en boucle ouverte, le coefficient de richesse KO2 est choisi égal à 1. Ces zones correspondent notamment à un fonctionnement avec une sonde λ en panne, ou avec une température d'air inférieure à un seuil d'entrée en boucle fermée, par exemple en cas de démarrage à froid du moteur, ou lorsque la boucle ouverte est imposée par le régime ou l'angle d'ouverture du papillon, par exemple en décélération ou à pleine charge, ou si le régime moteur N est supérieur à un seuil élevé donné, par exemple 4500 tr/min, et, d'une manière générale, chaque fois que la richesse visée diffère de 1.In the open-loop engine operating zones, the richness coefficient KO2 is chosen equal to 1. These zones correspond in particular to operation with a faulty λ probe, or with an air temperature below an input threshold in a closed loop, for example in the event of a cold start of the engine, or when the open loop is imposed by the speed or the opening angle of the throttle, for example in deceleration or at full load, or if the engine speed N is higher than a given high threshold, for example 4500 rpm, and, in general, each time the target wealth differs from 1.

Après correction par multiplication par le coefficient de richesse KO2, on modifie la valeur du décalage D ou du gain G par une autoadaptation cyclique, de manière à corriger toutes les dérives de ce coefficient de richesse KO2 pour qu'il reste voisin de 1. Dans cet exemple, on considère que KO2 est un coefficient correcteur multiplicateur de valeur nominale égale à 1.After correction by multiplication by the richness coefficient KO2, the value of the offset D or of the gain G is modified by a cyclic self-adaptation, so as to correct all the drifts of this richness coefficient KO2 so that it remains close to 1. In this example, we consider that KO2 is a corrective multiplier coefficient of nominal value equal to 1.

Cette autoadaptation est assurée de la manière à présent décrite à l'aide de la figure 3.This self-adaptation is ensured in the manner now described with the aid of FIG. 3.

Cette figure 3 représente trois plages caractéristiques de fonctionnement du moteur 1, définies par le régime moteur N en ordonnées et par la pression dans la tubulure P tub en abscisses, dans lesquelles il est possible d'effectuer les calculs cycliques d'autoadaptation pour un fonctionnement du moteur hors ralenti dans les plages 1 et 2, et au ralenti dans la plage 3.This FIG. 3 represents three characteristic operating ranges of the engine 1, defined by the engine speed N on the ordinate and by the pressure in the pipe P tub on the abscissa, in which it is possible to carry out the cyclic self-adaptation calculations for an operation engine idle in ranges 1 and 2, and idling in range 3.

Les plages 1 et 2 sont des plages de fonctionnement respectivement à basse et haute pression de tubulure définies chacune entre un seuil inférieur et un seuil supérieur de P tub, respectivement P1 et P2 ou P3 et P4, tels que P1 < P2 < P3 < P4, de sorte que les plages 1 et 2 ne sont pas adjacentes. De plus, les plages 1 et 2 sont définies entre un même seuil inférieur de régime N1, par exemple de 1200 tr/min, et un même seuil supérieur de régime N2, par exemple de 4000 tr/min.Tracks 1 and 2 are operating ranges respectively at low and high tubing pressure, each defined between a lower threshold and an upper threshold of P tub, respectively P1 and P2 or P3 and P4, such as P1 <P2 <P3 <P4 , so that tracks 1 and 2 are not adjacent. In addition, ranges 1 and 2 are defined between the same lower speed threshold N1, for example of 1200 rpm, and the same higher speed threshold N2, for example of 4000 rpm.

La plage 1 est celle dans laquelle l'autoadaptation cyclique est uniquement assurée sur le décalage D hors ralenti, tandis que dans la plage 2, l'autoadaptation est uniquement assurée sur le gain G.Range 1 is that in which the cyclic self-adaptation is only ensured on the offset D without idling, while in range 2, the self-adaptation is only ensured on the gain G.

Lorsque le point de fonctionnement du moteur, défini par son régime N et sa pression de tubulure P tub, est entré dans la plage 1 ou 2, dès que le calculateur 21 détecte, en fonction du signal de richesse R de la sonde λ et du coefficient de richesse KO2, qu'une autoadaptation de la richesse est nécessaire, il commande la vanne de purge 20 de façon à interdire son débit et commence l'autoadaptation modifiant la valeur du décalage D hors ralenti en plage 1 ou du gain G en plage 2. Il interdit donc la purge simultanément à l'autoadaptation dans les plages 1 et 2.When the engine operating point, defined by its speed N and its manifold pressure P tub, has entered range 1 or 2, as soon as the computer 21 detects, as a function of the richness signal R of the probe λ and the richness coefficient KO2, that a self-adaptation of the richness is necessary, it controls the purge valve 20 so as to prohibit its flow and begins the self-adaptation modifying the value of the offset D out of idle in range 1 or of the gain G in range 2. It therefore prohibits purging simultaneously with self-adaptation in ranges 1 and 2.

En plage 1, il autorise l'autoadaptation de D hors ralenti pendant au plus un nombre maximum de n1 cycles, par exemple égal à 2, grâce à un premier compteur qui est initialisé à cette valeur à la mise sous tension du calculateur et décrémenté de la valeur d'une unité à chaque cycle effectué. De même, en plage 2, le calculateur 21 autorise l'autoadaptation de G pendant au plus un nombre maximum de n2 cycles, par exemple égal à 1, grâce à un second compteur qui est également initialisé à cette valeur à la mise sous tension du calculateur, et décrémenté d'une unité à chaque cycle.In range 1, it authorizes the self-adaptation of D out of idle for at most a maximum number of n1 cycles, for example equal to 2, thanks to a first counter which is initialized to this value when the computer is powered up and decremented by the value of one unit for each cycle performed. Similarly, in range 2, the computer 21 authorizes the self-adaptation of G for at most a maximum number of n2 cycles, for example equal to 1, thanks to a second counter which is also initialized at this value when the power is turned on. calculator, and decremented by one at each cycle.

En plage 1, après n1 cycles d'adaptation du décalage hors ralenti D, si le second compteur n'est pas à zéro, le calculateur 21 autorise la purge, et il n'est plus possible d'adapter D. De même, en plage 2, après n2 cycles d'adaptation du gain G, si le premier compteur n'est pas à zéro, le calculateur autorise la purge et interdit la poursuite de l'adaptation du gain G.In range 1, after n1 cycles of adaptation of the offset without idling D, if the second counter is not at zero, computer 21 authorizes the purge, and it is no longer possible to adapt D. Similarly, in range 2, after n2 gain adjustment cycles G, if the first counter is not at zero, the computer authorizes the purge and prohibit further adjustment of gain G.

Par contre, dès que les deux compteurs sont à zéro, le calculateur 21 réinitialise les deux compteurs respectivement à n1 et n2, et autorise à nouveau des cycles d'autoadaptation, si nécessaire, en interdisant alors la purge.On the other hand, as soon as the two counters are at zero, the computer 21 resets the two counters respectively to n1 and n2, and again authorizes self-adaptation cycles, if necessary, then prohibiting the purging.

En résumé, lorsque l'adaptation d'un terme D ou G est autorisée, la purge est interdite par le calculateur 21. A chaque terme d'autoadaptation D et G est associé un compteur dans le calculateur 21. Chaque compteur est décrémenté d'une unité après chaque cycle d'autoadaptation de son terme associé. Lorsqu'un compteur est nul, l'autoadaptation de son terme associé est interdite et la purge autorisée. Les compteurs de décalage D hors ralenti et de gain G sont initialisés à chaque mise sous tension, puis lorsque les deux compteurs sont simultanément nuls.In summary, when the adaptation of a term D or G is authorized, the purging is prohibited by the computer 21. With each self-adaptation term D and G is associated a counter in the computer 21. Each counter is decremented by one unit after each self-adaptation cycle of its associated term. When a counter is zero, self-adaptation of its associated term is prohibited and purging is authorized. The offset D idle and gain G counters are initialized each time the power is turned on, then when the two counters are simultaneously zero.

Entre les plages 1 et 2, la purge n'est jamais interdite par le calculateur 21, quelles que soient les conditions d'autoadaptation choisies.Between ranges 1 and 2, purging is never prohibited by the computer 21, whatever the self-adaptation conditions chosen.

Pour cette raison, entre les seuils de régime N1 et N2, la purge du canister 16 par la vanne de purge 20 n'est pas interdite par le calculateur 21 sauf si le point de fonctionnement du moteur est dans la plage 1, et que le premier compteur n'est pas nul, ou que le point de fonctionnement du moteur est dans la plage 2 et que le second compteur n'est pas nul.For this reason, between the speed thresholds N1 and N2, the purging of the canister 16 by the purge valve 20 is not prohibited by the computer 21 unless the engine operating point is in range 1, and the first counter is not zero, or the engine operating point is in range 2 and the second counter is not zero.

La plage 3 de fonctionnement au ralenti est limitée par un seuil supérieur de régime moteur N qui est inférieur ou, au plus, égal au seuil inférieur N1 des plages 1 et 2. Par contre, en pression, la plage 3 peut s'étendre de part et d'autre du seuil inférieur de pression P1 de la plage 1, ou être toujours inférieur à P1. Cette plage de ralenti correspond à un régime faible et à un angle de papillon faible ou nul. Dans cette plage 3, l'autoadaptation est effectuée en substituant au terme de décalage D hors ralenti, un décalage en ralenti DR. A l'entrée dans la plage 3, le calculateur 21 interdit le débit de la vanne de purge 20, et commence l'autoadaptation cyclique de DR, choisi indépendant du régime moteur, et interrompt cette adaptation dès que la valeur de DR après un cycle donné est égale à celle obtenue après le cycle précédent. Le calculateur 21 autorise ensuite le débit de la vanne de purge 20.The idling range 3 is limited by an upper threshold of engine speed N which is lower or, at most, equal to the lower threshold N1 of ranges 1 and 2. On the other hand, under pressure, range 3 can extend from on either side of the lower pressure threshold P1 of range 1, or always be less than P1. This idle range corresponds to a low speed and a throttle angle weak or zero. In this range 3, the self-adaptation is carried out by substituting for the term offset D without idling, an offset in idling DR. On entering range 3, the computer 21 prohibits the flow of the purge valve 20, and begins the cyclic self-adaptation of DR, chosen independent of the engine speed, and interrupts this adaptation as soon as the value of DR after a cycle given is equal to that obtained after the previous cycle. The computer 21 then authorizes the flow rate from the purge valve 20.

L'autoadaptation de DR peut être autorisée pendant au plus un nombre maximum de n3 cycles, à l'aide d'un troisième compteur initialisé à chaque mise sous tension puis à chaque entrée en mode ralenti (entrée en plage 3). Mais, de préférence, le procédé consiste à répéter cycliquement l'autoadaptation de DR jusqu'à obtention d'une valeur constante qui est prise en compte pour le calcul de la durée d'injection. Après exécution des n3 cycles dans le premier cas, ou obtention d'une valeur constante de DR dans le second cas, le calculateur 21 autorise à nouveau la purge.DR self-adaptation can be authorized for at most a maximum number of n3 cycles, using a third counter initialized at each power-up and then at each entry in idle mode (entry in range 3). However, preferably, the method consists in cyclically repeating the self-adaptation of DR until a constant value is obtained which is taken into account for the calculation of the injection duration. After execution of the n3 cycles in the first case, or obtaining a constant value of DR in the second case, the computer 21 again authorizes the purge.

Le procédé d'autoadaptation de la richesse et d'autorisation de la purge du circuit de purge à canister ci-dessus décrit assure ainsi une dissociation entre l'autoadaptation et la purge, qui remédie aux inconvénients des procédés de l'état de la technique, et permet une bonne adaptation du premier ordre, et en particulier une bonne modulation du gain dans la plage 2.The method of self-adaptation of the richness and authorization of the purging of the canister purge circuit described above thus ensures a dissociation between the self-adaptation and the purge, which overcomes the drawbacks of the methods of the prior art , and allows a good first order adaptation, and in particular a good modulation of the gain in range 2.

La mise en oeuvre de ce procédé est assurée par le dispositif décrit ci-dessus, en particulier en référence à la figure 1, dans lequel le calculateur 21, qui est en fait une unité centrale de calcul et de commande, avec notamment les circuits de calcul, mémoires, compteurs, registres et autres circuits de régulation et commande, nécessaires et de structure connue, comporte au moins un microprocesseur ou microcontrôleur programmé et/ou réalisé de manière à commander le déroulement de ce procédé.The implementation of this method is ensured by the device described above, in particular with reference to FIG. 1, in which the computer 21, which is in fact a central computing and control unit, with in particular the circuits of calculation, memories, counters, registers and other regulation and control circuits, necessary and of known structure, comprises at least one microprocessor or microcontroller programmed and / or produced so as to control the progress of this process.

Claims (9)

  1. Process for auto-adaptation of the air/fuel ratio and permitting the purging of a purge circuit of an injection engine (1), for which the purge circuit comprises a canister (16) collecting fuel vapours coming from a tank (11) and connected to an inlet duct (4) of the engine (1) provided with an air valve or butterfly (5) for controlling the air flow, by means of an electrically controlled valve (20) of the canister (16), the flow through which is controlled by a computer (21) connected to sensors (26, 28) for the operating parameters of the engine (1) of which it receives at least signals (30) of rotation of the engine and signals (27, 30, 31) allowing the pressure (P tub) in the inlet duct (4) to be known, and an oxygen sensor in the exhaust gas of the engine, said computer (21) calculating an injection duration, transmitted to at least one injector (2) and obtained from a base injection duration (T inj B) expressed, in the case of a given engine regime (N), as a substantially linear crescent function of the pressure in the duct (P tub) with a shift (D) at the origin and an increase (G) which are drawn from maps as a function of at least the engine regime (N), and corrected taking into consideration a coefficient of the air/fuel ratio (KO2) determined as a function of the air/fuel ratio signal of the oxygen sensor (32) in the operating areas of the engine (1) in a closed loop and fixed equal to a nominal value in the operating areas of the engine (1) as an open loop, to ensure the setting of the operation of the engine at an air/fuel ratio equal to 1, the shift (D) and the increase (G) furthermore being the object of a cyclical auto-adaptation to ensure that the coefficient of the air/fuel ratio (KO2) remains close to its nominal value, by a correction of any drift of this coefficient of the air/fuel ratio (KO2) in at least one first phase of operation of the engine, at low pressure of the duct (P1, P2) by modification of at least the shift (D) and in at least a second range of operation of the motor, at high pressure of the duct (P3, P4) by modification of at least the increase (G),
    characterised in that it consists in :
    - preventing simultaneous auto-adaptation and flow through the purge valve (20),
    - permitting, at each entry to an auto-adaptation phase, this phase for at most a maximum number of n1 cycles, in the first phase of operation, and for at most a maximum number of n2 cycles in the second phase of operation,
    - in not permetting the flow through the purge valve (20) until a certain maximum number of auto-adaptation cycles, n1 or n2 respectively, have been performed, and
    - in not permetting a new auto-adaptation in shift (D) or in increase (G) until after all the permitted auto-adaptation shift and increase cycles have been performed.
  2. Process according to Claim 1, characterised in that it consists in only adapting the shift (D) or, respectively, the increase (G) for the auto-adaptation cycles performed only in the first or second range of operation of the engine respectively.
  3. Process according to any one of the preceding Claims, characterised in that it consists in selecting the maximum numbers of nl and n2 auto-adaptation cycles to be equal to, respectively, 2 and 1.
  4. Process according to any one of the preceding Claims, characterised in that it consists in not preventing the flow through the purge valve (20), irrespective of the auto-adaptation conditions, in the range (P2-P3) of operation of the engine which extends between said first and second ranges.
  5. Process according to any one of the preceding Claims, characterised in that it consists in preventing, at the entry of the engine into an idle phase, the flow through the purge valve (20), in substituting, for the auto-adaptation in shift (D), a cyclical auto-adaptation in idle shift (DR) which is interrupted as soon as the value of the idle shift (DR) after a given cycle is sufficiently close to that obtained after the preceding cycle, and in permitting, subsequently, the flow through the purge valve (20).
  6. Process according to Claim 5, characterised in that it consists, at each entry into the phase of auto-adaptation in idle shift (DR), in permitting this for, at most, a maximum number of n3 cycles.
  7. Process according to Claim 5, characterised in that it consists in repeating, cyclically, the auto-adaptation in idle shift (DR) until a constant value of idle shift has been obtained.
  8. Process according to any one of Claims 5 to 7, characterised in that it consists in restricting the range of operation in idle to an upper engine regime threshold which is less than or equal to a lower engine regime threshold (N1) for the first and second ranges of operation corresponding to the auto-adaptation in shift (D) and, respectively, in increase (G).
  9. Device for auto-adaptation of the air/fuel ratio and permitting a purging of a purge circuit (16, 17, 19, 20) with a canister (16) for an injection engine (1), comprising a computer (21) connected to sensors (26, 28) for operating parameters of the engine (1) and to a sensor for the oxygen in the exhaust gas of the engine (1), and controlling an electrically-controlled valve (20) connecting the canister (16) to an inlet duct (4) provided with an air valve (5) controlling the air flow, said computer (21) calculating an injection duration, applied to at least an injector (2) or the motor (1) and obtained from a base injection duration (T inj B) expressed as a function of the pressure in the inlet duct (4) with a shift (D) at the origin and an increase (G) drawn from maps in the memory in the computer (21), and corrected using a coefficient of the air/fuel ratio (KO2) determined by the computer (21) as a function of the air/fuel ratio signal (R) of the oxygen sensor in operation in a closed loop and equal to a nominal value in operation in an open loop, to ensure the setting of the operation of the engine (1) at an air/fuel ratio equal to 1, the computer (21) performing a cyclical auto-adaptation of the shift (D) and the increase (G) to ensure that KO2 remains close to its nominal value thereof, by correction of any drift of KO2, characterised in that the computer (21) comprises at least one microprocessor programmed and/or produced in such a manner as to control the development of the process according to any one of Claims 1 to 8.
EP19940401643 1993-07-20 1994-07-18 Process and apparatus for auto-adaptation of air/fuel ratio in an internal combustion engine with canister purge system Expired - Lifetime EP0637685B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9308883A FR2708047B1 (en) 1993-07-20 1993-07-20 Method and device for self-adaptation of richness and authorization of purging of a purge circuit in a canister of an injection engine.
FR9308883 1993-07-20

Publications (2)

Publication Number Publication Date
EP0637685A1 EP0637685A1 (en) 1995-02-08
EP0637685B1 true EP0637685B1 (en) 1997-01-08

Family

ID=9449404

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19940401643 Expired - Lifetime EP0637685B1 (en) 1993-07-20 1994-07-18 Process and apparatus for auto-adaptation of air/fuel ratio in an internal combustion engine with canister purge system

Country Status (4)

Country Link
EP (1) EP0637685B1 (en)
DE (1) DE69401400T2 (en)
ES (1) ES2095727T3 (en)
FR (1) FR2708047B1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2775315B1 (en) * 1998-02-25 2000-05-05 Magneti Marelli France METHOD AND DEVICE FOR FAST SELF-ADAPTATION OF RICHNESS FOR AN INJECTION ENGINE WITH AN OXYGEN PROBE IN EXHAUST GASES
DE102004057210B4 (en) 2004-11-26 2011-12-22 Continental Automotive Gmbh Method for controlling a tank ventilation

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57165644A (en) * 1981-04-07 1982-10-12 Nippon Denso Co Ltd Control method of air-fuel ratio
FR2567962B1 (en) * 1984-07-23 1989-05-26 Renault ADAPTIVE METHOD FOR REGULATING THE INJECTION OF AN INJECTION ENGINE
DE3639946C2 (en) * 1986-11-22 1997-01-09 Bosch Gmbh Robert Method and device for compensating for the tank ventilation error in an adaptively learning fuel supply system
DE3642476A1 (en) * 1986-12-12 1988-06-23 Bosch Gmbh Robert Method and device for the inclusion of additive and multiplicative correction variables in a continuous fuel feed system

Also Published As

Publication number Publication date
DE69401400T2 (en) 1997-05-07
FR2708047A1 (en) 1995-01-27
FR2708047B1 (en) 1995-09-22
ES2095727T3 (en) 1997-02-16
EP0637685A1 (en) 1995-02-08
DE69401400D1 (en) 1997-02-20

Similar Documents

Publication Publication Date Title
EP1769153B1 (en) System for controlling the function of a diesel engine in a motor vehicle connected to an oxidation catalyst
FR2922598A1 (en) PROCESS FOR DETERMINING THE FLAMMABILITY OF FUEL OF UNKNOWN QUALITY.
FR2763650A1 (en) SYSTEM FOR CONTROLLING A PRESSURE SENSOR OF A FUEL SUPPLY SYSTEM OF AN INTERNAL COMBUSTION ENGINE, IN PARTICULAR OF A MOTOR VEHICLE
FR2877695A1 (en) METHOD FOR MANAGING AN INTERNAL COMBUSTION ENGINE AND DEVICE FOR IMPLEMENTING SAID METHOD
EP1058781B1 (en) Method and device for fast automatic adaptation of richness for internal combustion engine
FR2750454A1 (en) METHOD FOR DETERMINING THE LOAD SIGNAL OF AN INTERNAL COMBUSTION ENGINE WITH EXTERNAL RE-INJECTION OF EXHAUST GASES
EP0686762A1 (en) Method and apparatus for determining specific parameters of injectors for combustion engines, in particular diesel engines with pre-injection
FR2787512A1 (en) METHOD AND DEVICE FOR CONTROLLING AN INTERNAL COMBUSTION ENGINE
EP0637685B1 (en) Process and apparatus for auto-adaptation of air/fuel ratio in an internal combustion engine with canister purge system
FR2707348A1 (en) Method and apparatus for controlling an internal combustion engine
FR2847944A1 (en) I.c. engine fuel/air mixture regulating procedure with multiple injection consists of adjusting fuel mass on each injection operation
EP1862659A1 (en) Method and device for correcting the flow of a so-called pilot fuel injection in a direct-injection diesel engine of the common rail type, and engine comprising such a device
WO1996004473A1 (en) Method for controlling the good operation of the air assistance to a fuel injector of an internal combustion engine, and corresponding device
EP0636778B1 (en) Method and apparatus for correcting the injection time as a function of the purge flow of a canister purge system in a fuel injected engine
EP1787020B1 (en) System for controlling the operation of a diesel engine of a motor vehicle
FR3101673A1 (en) Method of adjusting the richness of a spark-ignition internal combustion engine
FR2871195A1 (en) Internal combustion engine monitoring process for motor vehicle, involves adjusting controlled variable on value from requests on engine`s output variable if request different from pedal actuation request exists, or on actuation based value
FR2740176A1 (en) SYSTEM AND METHOD FOR DOUBLE CONTROL LOOP FOR INTERNAL COMBUSTION ENGINE
EP1597468B1 (en) Method for calculating fuel injector gain
FR2708046A1 (en) Method and device for correcting the injection duration on the basis of the purge flow rate of a canister-type purge circuit for a fuel-injected engine
FR2708049A1 (en) Method and device for estimating the fuel content of a canister-type purge circuit for a fuel-injected engine
FR2857055A1 (en) METHOD FOR MANAGING AN INTERNAL COMBUSTION ENGINE
EP0884466A1 (en) Method and apparatus for correcting the air/fuel ratio of an internal combustion engine
FR2466618A1 (en) FUEL CONTROL SYSTEM FOR INTERNAL COMBUSTION ENGINE
FR2851298A1 (en) Thermal engine control process, involves defining mass charging that should be applied to combustion chamber, from bunch of curve characteristics, desired torque, and size explaining desired air/fuel ratio

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE ES GB IT SE

17P Request for examination filed

Effective date: 19950114

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

17Q First examination report despatched

Effective date: 19960307

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE ES GB IT SE

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2095727

Country of ref document: ES

Kind code of ref document: T3

REF Corresponds to:

Ref document number: 69401400

Country of ref document: DE

Date of ref document: 19970220

ITF It: translation for a ep patent filed

Owner name: 0508;11TOFSTUDIO TORTA S.R.L.

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19970411

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 20070620

Year of fee payment: 14

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20070711

Year of fee payment: 14

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20070717

Year of fee payment: 14

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20070710

Year of fee payment: 14

EUG Se: european patent has lapsed
GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20080718

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20090203

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080718

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080718

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20080719

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080719

PGRI Patent reinstated in contracting state [announced from national office to epo]

Ref country code: IT

Effective date: 20091001

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20090727

Year of fee payment: 15

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080719

PGRI Patent reinstated in contracting state [announced from national office to epo]

Ref country code: IT

Effective date: 20091001