FR2764943A1 - METHOD FOR CONTROLLING AND / OR REGULATING AN INTERNAL COMBUSTION ENGINE WITH MULTIPLE COMBUSTION CHAMBERS - Google Patents

Abstract

Engine with several combustion chambers equipped each time with an injector for direct injection. A pressure sensor measures the pressure acting on the fuel. A control device (22) controls and regulates a quantity influencing the combustion of the fuel in the combustion chambers. The apparatus (22) determines the pressure applied to the fuel for the next injection from an average value (M) and a correction value (DeltaZyl1-DeltaZyl4). This allows a more precise dosage of the mass of fuel to be injected.

Description

Description:

  The present invention relates to a method of implementing an internal combustion engine with several combustion chambers, in particular of a motor vehicle, according to which the fuel is injected directly under pressure into the combustion chambers of the combustion engine. internal, and according to which we measure the pressure acting on

fuel.

  Such a process is known in particular in vehicles.

  cells fitted with an internal combustion injection engine

  direct to diesel or petrol. An injector is associated with each

  that combustion chamber to directly inject the fuel

  rant under pressure in the associated chamber. To generate the pressure acting on the fuel, a pump is provided.

  which supplies the injectors with fuel.

  In general, the pump does not generate a constant pressure. The pump is for example a piston pump, so that the pressure varies according to the number of pistons and the position of each piston. A pressure sensor measures the variable pressure generated by the pump and applied

to fuel.

  Among other things, to dose the fuel mass to

  inject into the combustion chambers, the pressure acts

  Health on the fuel with each injection is essential.

  This is how, for example, for the same mass of fuel injected, under high pressure, a short injection time is sufficient, while conversely if the pressure is low, the injector is controlled to stay longer at

open state.

  The problem which arises is that on the one hand the pressure acting on the fuel at each injection is not known beforehand and on the other hand this pressure must

  nevertheless be taken into account to measure the mass of

  rant to be injected during the injection.

  This problem is solved by the methods known in

  starting from the pressure values measured before-

  we define a predictable pressure for each injection

  and according to this one then corrects the mass of car-

  drug to inject. But this translates into a relative dosage

  the mass of fuel to be injected is imprecise. The object of the present invention is to develop a method making it possible to precisely determine the pressure acting provisionally on the fuel during an injection.

  This problem is solved by a method or a mo-

  internal combustion torch corresponding to the type defined above

  above, characterized in that the acting pressure is determined

  health forecast on fuel during the next injection in one of the combustion chambers

  starting from an average value and a correction value.

  By splitting the determination of the pre-

  visible in an average value and a correction value, we

  can also use the average value separately.

  This allows, as will be described later-

  use the average value for the order and / or the

  pressure regulation acting on the fuel.

  Preferably, a regulation circuit is established which regulates the average value over a desirable reference value. As a result, the average value varies in principle only slowly. If the average value is determined from the previous pressure measurements, due to the essentially slow variation of the average value, it can be estimated that the average value thus obtained essentially corresponds to the effective average value of

the next injection.

  The use of the mean value for the com-

  control and / or pressure regulation acting on the car-

  burant thus enables the following injection, the average value of which cannot yet be measured, essentially corresponds

  to the average value obtained from the previous measurements.

  This forecasting possibility makes the average value partial.

  particularly suitable for obtaining the mass of fuel to be

  inject into a combustion chamber.

  If as will be described later,

  we use the average value to determine the mass of

  fuel to be injected into a combustion chamber, no

  not yet taken into account all the pressure acting on the fuel

  rant. It is also necessary to take into account the deviations of the foreseeable pressure acting on the fuel from the above average value. These deviations ultimately correspond to variations in pressure, for example as a function of the position of the piston in the case of a piston pump. Gold,

  these deviations correspond precisely to the value of cor-

  rection. Thus the correction value represents the deviation

  tion varying rapidly from one injection to another of the

  foreseeable fuel pressure, compared to the average value of this pressure.

  As a result, the mass of fuel to be injected

  ter can be determined according to the average value and the correction value. The average value thus varies in principle only slowly, so that one cannot

  principle to have error when determining the mass of car-

  drug to inject. On the other hand, the correction value varies rapidly with the injection. These variations are however

  low compared to the average value.

  The correction value is determined from the pressure measurements acting on the fuel. As we only measure the pressure of previous injections, and that

  the predicted pressure for the following injection is deduced therefrom

  However, it is possible to have an error when determining the correction value. However, since the correction value changes quickly, it is possible that the determination of the

  correction value is also affected by an error.

  It follows overall that if an error occurs when determining the mass of fuel to be injected, this error comes essentially from an error related to the determination of the correction value but not to that of

  the average value. As changes in the value of cor-

  rection are low compared to the average value like

  this has been indicated, the error generated remains small.

  Unlike the state of the art, according to which the whole value of the pressure measured can be the cause of a fault when determining the mass of fuel at

  inject, the present invention is based on the fact that an er-

  ror linked to the division into an average value and into a

  their correction only affects the variable correction value, which is low and not the average value. It follows that a possible error when the mass of fuel to be injected is determined, according to the method of the invention, is in all cases lower than in

  the state of the art. This results in a better dosage of the mass of fuel to be injected and thus in a better com-

  bustion in the combustion chambers. This results in advantages such as, for example, more regular operation.

  Linking the internal combustion engine, a reduction in fuel consumption and / or a reduction in the emission of polluting exhaust gases. Other advantages of the invention are the following: the influence the variable transfer power of the pump supplying the different cylinders with fuel is taken into account by the method of the invention and can be corrected. Similarly, the angular inaccuracies in mounting the pump relative to the camshaft are taken into account and corrected by the method of the invention, so that it is not necessary to mount the pump precisely

on the angular plane.

  According to an advantageous development of the invention, the correction value is deduced either from at least one measurement of the pressure acting on the fuel during the previous injection of fuel into the same chamber

  combustion or from at least one measurement of the pressure

  fuel acting during the previous injection

  fuel in the previous combustion chamber. The va-

  their correction thus depends either on the last injection in time, in the same combustion chamber, or on the last injection in time in one of the combustion chambers. In both cases, the pressure acting on the

  fuel is measured at each injection and is set to

  moire. When calculating the mass of fuel to be injected into the next combustion chamber, use either the value stored in memory corresponding to the same combustion chamber, or the value stored in memory of the combustion chamber.

  combustion in which the last injection took place

  tion, as a correction value and thus one determines in my-

  forecast pressure acting on the fuel.

  According to another advantageous development of the invention, the correction value is determined from

  the measurement of the pressure acting on the fuel is felt

  approximately in the middle of the injection, i.e. from the

  of the pressure acting on the fuel, in particular shortly before and after injection, by making an average or a similar operation or even by measuring the pressure acting on the fuel, shortly before injection by proceeding by

  adaptation or the like.

  In theory, it would be possible to measure in con-

  The pressure acting on the fuel during the entire injection, that is to say during the entire duration of the injection, would represent the most precise basis for determining the value of the correction. In practice, such a process cannot be carried out because of the means which would be

  required. This is why, according to the invention, it is possible to

  ble to determine only once the pressure acting on the

  fuel, substantially in the middle of the injection and

  deduct the correction value. Similarly, the invention makes it possible to measure the pressure acting on the fuel before and after

  injection and deduce the correction value. These pos-

  sibilities can also be used in an alternative or cumulative way. These possibilities make it possible to determine correction values which, on the one hand, have great precision and reliability and which, on the other hand, can be achieved with acceptable means, in particular

means of calculation.

  According to another advantageous development of the invention, the average value is used to order

  and / or regulate the pressure acting on the fuel. The va-

  their average thus represents a real value that the

  control and / or regulation must regulate on a value of

  instructions. Thus, the average value is controlled and / or regulated

  lée on a set value which is used for example in a particularly advantageous way to determine the

  mass of fuel to be injected. The dual use of the average value, on the one hand for controlling and / or regulating the pressure acting on the fuel and on the other hand5 to determine the mass of fuel to be injected, between

  very depending on the pressure acting on the fuel makes it possible to optimize this last determination of the mass of fuel to be injected by a control and / or regulation

  appropriate pressure acting on the fuel.

  It is particularly advantageous for the set value of a pressure applied to the fuel during the next injection of fuel into one of the combustion chambers, in particular as a function of the speed of rotation of the internal combustion engine and / or of an applied load

  internal combustion engine and / or an operating mode

  stratified and / or a homogeneous operating mode of the

  internal combustion engine. In this way, the determination

  tion of the mass of fuel to be injected can be combined in a particularly good way with the control and / or regulation of the pressure acting on the fuel. Furthermore, this makes it possible to obtain that the average value varies essentially only slowly. This also offers the advantages already mentioned, according to which the average value taken as

  that such will in principle not lead to any error when determining-

  will undermine the mass of fuel to be injected.

  According to another advantageous development of the invention, during the next injection of fuel into one of the combustion chambers, the pressure acting predictively on the fuel is used, for the

  fuel mass control and / or regulation

  eject into the combustion chamber. As already stated,

  the possible error which then occurs on the pressure obtained

  held, forecast acting on the fuel will be inferior

  higher than that of the state of the art. The control and / or regulation of the mass of fuel to be injected is therefore

  made more precise by the method of the invention. That in-

  drags that the internal combustion engine applying the pro-

  yielded from the invention will operate more regularly and more flexibly, that is to say that there will be less shaking and at the same time the fuel consumption will be reduced as well as the emission of exhaust gases. It is particularly important to carry out the method according to the invention in the form of an electrical memory provided in particular for the control device of an internal combustion engine, in particular of a vehicle. The electrical memory contains a program suitable for a computing device, in particular a microprocessor for unwinding and executing the method according to the invention. Thus, the invention will be executed by a program stored in an electric memory, so that the memory containing this program can in the same way, carry out the process by executing

of his program.

  Other characteristics, applications and advantages

  stages of the invention will appear on reading the description

  following tion of different embodiments of the invention which are shown in the accompanying drawings in which:

  All the characteristics described or represented

  tees as such or in any combination

  belong to the invention regardless of the characteristics

  summarized in the claims or their reminder as well

  that regardless of their wording and their presentation in

the description or in the drawings.

So:

  - Figure 1 shows a block diagram of an example of a

  reading of a method according to the invention for the implementation of an internal combustion engine equipped with several combustion chambers, in particular of a motor vehicle and, - Figure 2 shows a diagram of the signals obtained in the

block diagram of Figure 1.

  The example of embodiment of FIG. 1 corresponds to

  pond to an internal combustion engine with four cylinders, that is to say four combustion chambers. An injector is

  associated with each combustion chamber for direct injection

  the fuel in the combustion chamber. Fuel

  is preferably gasoline, but one can also use

  use diesel. To inject the fuel into the combustion chambers, a pressure is exerted on the fuel

  which is supplied for example by a three-cylinder pump.

  To measure the pressure acting on the fuel, a pressure sensor is needed, for example placed in the pump area. To influence the pressure acting on the fuel, a pressure control valve is provided with, in the opening position, a reduction in pressure, for example.10 The mass of fuel injected by an injector depends, among other things, on the duration of injection during which the injector is open as well as the pressure acting on the fuel at the time of injection. If we want to inject

  a certain mass of fuel in a combustion chamber

  tion, the necessary injection time must be determined, depending on the pressure acting on the fuel during this injection. If the pressure is high, the duration

  injection will be low and vice versa.

  To determine the duration of a certain injec-

  tion, it is necessary to make a preliminary calculation. For that you need

  also take into account the injection pressure

  fuel. However, this future pressure is not known anywhere, so this pressure must be calculated

in another way.

  In FIG. 1, the pressure measured by the pressure sensor and acting on the fuel is designated by (up) with the number of the combustion chamber concerned.

  under the reference Zyl. The pressure (up) and the com-

  Zyl bustion are applied to a block 1 which determines the pressure acting on the fuel. Block 1 linearizes or normalizes the measured pressure (up) according to function 2. The

  function 2 provides a pressure (p) at the output which is applied

  quée a switch 3, a generator of average value 4 and a generator of correction 5. The generator of value

  mean 4 generates a mean value M applied to the switching

  corrector 3. The correction generator 5 generates the correction values DeltaZyll, DeltaZyl2, DeltaZyl3 and DeltaZyl4, and

  these signals are applied to a command and / or a regulation

  tion 6 which influences the mass of fuel to be injected into

a combustion chamber.

  The mean value M is formed by the mean value generator 4 as a function of time and / or of the angle. In particular, the average value M is calculated by an equidistant input over time and / or according to the angles for the

pressure (p).

  According to FIG. 2, it is assumed that the three-cylinder pump and the four-cylinder internal combustion engine are respectively tuned so that a path of an angle of 360 by the pump corresponds exactly to a path of 360 through the shaft cam of the internal combustion engine. As a result, the pressure generated by the pump presents three waves on 360 whereas for this passage, the

  internal combustion engine provides four injections.

  For other numbers of cylinders of the internal combustion engine and / or the pump and / or other multiplication or reduction ratios between the internal combustion engine and the pump, this can be taken into account by a correction function and a field of correction characteristics. In the predetermined example according to FIG. 2, it

  it is possible to calculate the mean value M from four

  tre measurement values Ml, M2, M3, M4 which correspond to the pressure (p) at three successive instants, preceding each

  times just an injection. The injection is shown in the fi

  gure 2 by a tiZyll-tiZyl4 injection duration, for each

  of the four cylinders Zyll-Zyl4. The four instants succeed

  sifs each have an interval of 90 from tree angle to

  cams and are thus angularly equivalent.

  The four measurement values Ml, M2, M3, M4 are

  added by the mean value generator 4 to give

  ner an average, that is to say divided by 4; the value

  mean M is shown in Figure 2.

  Correspondingly, it is also possible

  ble at constant time intervals, to enter the press-

  sion (p) and process it to give an average value M. It is also possible to combine the determination of the average value M as a function of angle and time. That

  can for example do in that depending on the rotation speed of the internal combustion engine, one switches from a determination as a function of time to a determination as a function of the angle and vice versa.

  For normal variations in pressure (p), that is to say if dp / dt is less than a predetermined threshold S, the switch 2 occupies the position shown, so that the mean value M is transmitted as the actual value (pi) of the pressure acting on the fuel. On the other hand, for large variations in pressure (p), for example

  after start-up, i.e. when dp / dt is greater than threshold S, the switch is switched by a block 7 and the pressure (p) is transmitted directly as the actual value15 (pi) of the pressure acting on the fuel.

  The actual value (pi) of the pressure acting on

  the fuel is applied to a regulating means 8; this-

  this regulates this actual value (pi) to a setpoint (ps). The set value (ps) is predetermined depending on whether the internal combustion engine is in homogeneous mode or in stratified mode or whether it is in the start-up phase or in the post-start-up phase. This is obtained using the selection bits B-SCHICHT and START

  which switch the associated switches 9, 10.

  The homogeneous mode designates the operating mode

  internal combustion engine that the fuel

  is injected into the combustion chamber during the aspiration phase

  tion. Contrary to this, in stratified mode, the fuel is injected during the compression phase in the chamber

  of combustion of the internal combustion engine.

  When the internal combustion engine is

  in homogeneous mode after start-up, a value is predetermined

  their (p) -homogeneous-cons as setpoint (ps). If the internal combustion engine is in stratified mode after starting, a value (p) and - layer and cons is predetermined as the set value (ps). If during startup,

  the internal combustion engine is in homogeneous mode,

  determines a value (p) - start-homogeneous-cons as set point value tl (ps). If the internal combustion engine is in stratified mode during start-up, a value (p) -depart-layer-cons is preset as the set value (ps). In particular, the values (p) homogeneous-cons and (p) layer-cons are determined using characteristic fields 11, 12 from the speed of rotation (n) of the

  internal combustion engine and the load (m) applied to the engine. After a comparison 13 between the value of

  sign and the actual value, the difference between the value of

  setpoint (ps) and the actual value (pi) is applied to a re-

  regulator (pi) 14 whose regulation constants (kp) and

  (ki) are formed by blocks 15, 16 by the functions ap-

  properties or fields of characteristics. In addition the re-

  regulator (pi) 14 has a minimum value and a maximum value MIN, MAX and is reset for example

  when the engine stops or when there is a significant change in the setpoint. The regulation value generated by the regulator (pi) 14 is added to the set value 20 (ps) 17 so that, using a function or a curve

  characteristic 18, it can be adapted to a control valve

  pressure demand influencing the pressure. Using another characteristic field 19, the regulation value is subjected to a multiplication 20 for a correction of

  voltage as a function of the vehicle's battery voltage UBatt

  cule. Finally, the signal generated in this way is converted to

  using block 21 as a function of the frequency fDSV in a report

  working port OUT, which then controls the com- petition valve

pressure demand.

  For normal variations in pressure (p), i.e. if the mean value M corresponds to the actual value (pi), the mean value M is regulated with regulation 8 to the set value (ps) . As the pressure oscillations (p), as assumed, are below the threshold

  predetermined S, the average value M changes only slowly.

  The variation is thus dependent on the variation of the

  their setpoint (ps) due to regulation 8 and thus the speed of rotation of the internal combustion engine and the load applied to it. The slow variation of the mean value M also appears in FIG. 2, as being constant when the camshaft travels an angle of 360.

  The correction values specific to the DeltaZyll, DeltaZyl2, DeltaZyl3, DeltaZyl4 cylinders can also

  This can also be determined in different ways by the correction value generator 5. This will be described below by way of example using the correction value DeltaZyll. For the other DeltaZyl2 correction values,

  DeltaZyl3, DeltaZyl4, we will apply the same process. It is possible to determine the value of cor-

  DeltaZyll rection by detecting, adding or integrating the pressure (p) of the correction value generator 5 during

  the entire injection time tiZyll of the Zyll cylinder. That cor-

  responds to the most precise determination of the value of

DeltaZyll correction.

  It is also possible to determine the value

  DeltaZyll correction by detecting the pressure (p)

  on average over time for the duration of injection

  tiZyll and if necessary by using it with a coefficient.

  This gives a DeltaZyll correction value which is relati-

  if the pressure (p) remains essentially constant

  aunt during the tiZyll injection period.

  It is also possible to determine the DeltaZyll correction value by detecting the pressure (p) shortly before the start of the injection and may after the end of

  injection. These measurement values are then used in low

  the average and, if necessary, applying a coefficient

  cient. This DeltaZyll correction value is relatively

  imprecise because of the average value if the pressure (p) di-

  minue depending on the duration of injection tiZyll.

  It is also possible to determine the DeltaZyll correction value by detecting the pressure (p) shortly before the start of the injection. From this value and according to the appropriate adaptation process, we can conclude that

  the change in pressure during the injection time ti-

Zyll.

  Possibilities described above can also

  They can also be used alternatively or cumulatively.

  In the possibilities described, we detect all

  days pressure (p) before and / or during an injection.

* This injection can be either the last injection in the same combustion chamber, or the last injection in

  any of the combustion chambers.

  In Figure 2, there is shown by way of example the second possibility mentioned above corresponding to the same combustion chamber. From there we calculate for example the DeltaZyl4 correction value for the next injection of fuel into the fourth cylinder Zyl4 according to

  Figure 2 from the pressure (p), substantially in

  their average of the duration of injection tiZyl4 of the last fuel injection in the same fourth cylinder Zyl4.

  DeltaZyll-DeltaZyl4 correction values

  are applied to the command and / or regulation 6 which deter-

  mine the mass of fuel to be injected into a

  combustion. This mass of fuel to be injected must be

  completed beforehand based on a large number of para-

  meters from the internal combustion engine. Among other things, it is also necessary, as already indicated, to take into account the pressure acting in a forecast manner during a

fuel injection.

  This pressure acting predictively

  on the fuel during the next injection deter-

  mine from the average value M and the cor-

  section depending on each DeltaZyll-DeltaZyl4 cylinder.

  If, for example, we want to determine

  Mining the pressure acting on the fuel during the next injection into the combustion chamber of the first Zyll cylinder, the average value M is calculated as described. The DeltaZyll correction value is calculated according to one of the possibilities described and calculation is done either from the previous injection, that is to say in

  upstream of 720 for the first Zyll cylinder; we can also

  ment use the previous fuel injection of 180 in another cylinder, that is to say according to figure 2,

  injection into the second Zyl2 cylinder.

  The average value M and the corresponding correction value DeltaZyllDeltaZyl4 represent the pressure

  predictable acting on the fuel during the following injection

  boasts. Using the mean value M and the value of

  correction above, we can calculate forecast-

  pressure. This forecast calculation of the pressure is then used to determine in particular the injection time tiZyll-tiZyl4 to globally inject the optimum fuel mass for the respective operating state of the engine at

  combustion in the combustion chamber.

  As described above, the value

  average M varies in principle only slowly. So the cal-

  butts based on the mean value M are not

  tainted with error. The DeltaZyll- correction value

  DeltaZyl4 varies however more quickly as it appears

  in Figure 2. The variations are small, however,

  comparison to the average value M. For this reason, for the

  preliminary calculation on the basis of the correction value evo-

  we can expect mistakes. But like the varia-

  correction value are small, these errors

are relatively small.

  The whole process described above is carried out

  ted by a control device 22. The control device 22 can for example be a programmed microprocessor comprising

  memories and other components, integrated into the vehicle.

  The control unit 22 receives the signals necessary for the execution of the method inter alia from the respective sensors with respect to the pressure sensor to generate

  according to the method described, the signals necessary for the

  commands for example actuators such as injector control

  pressure control valves or valves.

  According to a variant, the average value M is determined from measurements depending on time and / or the angle, in particular from measurements of time and / or angle,

  of the pressure p acting on the fuel.

  According to another variant, the setpoint ps is compared to the average value M. The memory used is, according to an example, a

ROM read only memory.

  Finally, the invention relates, as already indicated,

  an internal combustion engine especially for a vehicle

  tomobile with several combustion chambers to which is associated

  each time injector injected, to directly inject

  fuel in the corresponding combustion chamber,

  taking a pump generating a pressure applied to the fuel

  rant supplying the injectors, a pressure sensor to measure the pressure acting on the fuel and a device

  control 22 for controlling and / or regulating quantities

  influencing the combustion of fuel in the chambers of

combustion.

RE V E N D I C A T I ON S

  1) Method for implementing an internal combustion engine

  dull to several combustion chambers, in particular of a motor vehicle, according to which the fuel is injected directly under pressure into the combustion chambers of the internal combustion engine, and according to which the pressure acting on the fuel is measured, characterized in that '' the pressure acting on the fuel10 during the next injection into one of the combustion chambers is determined on the basis of an average value (M) and a correction value (DeltaZyll-DeltaZyl4) 2 ) Method according to claim 1, characterized in that the correction value (DeltaZyll-DeltaZyl4) is determined from at least one pressure measurement (p) acting on the fuel during the previous injection of fuel into the

same combustion chamber.

  3) Method according to claim 1, characterized in that the correction value (DeltaZyll-DeltaZyl4) is determined at

  from a measurement of the pressure (p) acting on the fuel

  during the previous injection of fuel into the

previous combustion chamber.

  4) Method according to any one of claims 2 or 3,

  characterized in that the correction value (DeltaZyllDeltaZyl4) is determined at

  from the measurement of the pressure (p) acting on the fuel

  rant substantially in the middle of the injection.

   ) Method according to any one of claims 2 and 3,

  characterized in that the correction value (DeltaZyllDeltaZyl4) is determined at

  from the measurement of the pressure (p) acting on the fuel

  especially shortly before and shortly after the injection while

  the average or by proceeding in a similar manner.

  6) Method according to any one of claims 2 and 3,

  characterized in that the correction value (DeltaZyllDeltaZyl4) is determined at

  from the measurement of the pressure (p) acting on the fuel

  especially shortly before injection using an adapter

tion or the like.

  7) Process according to any one of the preceding claims.

teeth, characterized in that

  the average value (M) is determined from dependent measurements

  during time and / or the angle, in particular from time and / or angle measurements, of the pressure (p) acting on the fuel.

  8) Process according to any one of the preceding claims.

  teeth, characterized in that the average value (M) is used to control and / or regulate

  (8) the pressure acting on the fuel.

  9) Method according to claim 8, characterized in that

  a setpoint (ps) of a pressure is determined,

  hatched to act on the fuel during the following injection

  boasts of fuel in one of the combustion chambers.

   ) Method according to claim 9, characterized in that

  the setpoint (ps) is determined as a function of the vi-

  rotation size (n) of the internal combustion engine and / or

the load (m) applied to the motor.

  11) Method according to any one of claims 9 or

  , characterized in that the setpoint (ps) is determined in accordance with a

  stratified or homogeneous operation for the combustion engine

internal tion.

  12) Method according to any one of claims 9 to

  11, characterized in that the setpoint (ps) is compared with the average value

(M).

  13) Process according to any one of the preceding claims.

  teeth, characterized in that the forecast pressure acting on the fuel during the next injection of fuel into one of the combustion chambers, is used for the control and / or regulation (6) of the mass of fuel to be injected into the room of

combustion (tiZyll-tiZyl4).

  14) Electric memory, in particular ROM read-only memory for a

  control unit (2) of an internal combustion engine no-

  especially of a motor vehicle containing a program which applies to a computer, in particular a microprocessor for

  the execution of a process according to any one of the claims

cations 1 to 13.

   ) Internal combustion engine especially for a vehicle

  automobile with several combustion chambers which is

  associated each time with an injector, to directly inject

  fuel in the corresponding combustion chamber,

  taking a pump generating a pressure applied to the fuel

  rant supplying the injectors, a pressure sensor for measuring the pressure acting on the fuel and a control device (22) for controlling and / or regulating quantities influencing the combustion of fuel in the combustion chambers, characterized in that

  the control unit (22) determines the forecast pressure

  applied to the fuel for the next injection into one of the combustion chambers, from a value

  mean (M) and a correction value (DeltaZyll-

  DeltaZyl4). 16) Internal combustion engine according to claim 15, characterized in that the control device (22) determines the correction value

  (DeltaZyll-DeltaZyl4) either from a measurement of the pressure

  sion (p) acting on the fuel during the previous injection

  fuel pitch in the same combustion chamber or at

  from a measurement of the pressure (p) acting on the fuel

  during the previous injection of fuel into the

previous combustion chamber.

  17) Internal combustion engine according to any one of

claims 15 or 16,

  characterized in that the control unit (22) determines the correction value

  (DeltaZyll-DeltaZyl4) either from the measurement of the pressure

  sion (p) acting on the fuel substantially in the middle of the injection, either from the measurement of the pressure (p) acting on the fuel in particular just before or just after the injection by averaging or applying a

similar process.

  18) Internal combustion engine according to any one of

claims 15 to 17,

  characterized in that the next time fuel is injected into one of the combustion chambers, the control unit (22) uses

  the forecast pressure applied to the fuel for

  order and / or regulate (6) for the mass of fuel to be injected

  ter in the combustion chamber (tiZyll-tiZyl4).