JP4004656B2 - Internal combustion engine control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an internal combustion engine control apparatus capable of adjusting the fuel supply amount, ignition timing, and exhaust gas recirculation amount of an internal combustion engine.
[0002]
[Prior art]
For example, Japanese Patent Publication No. 3-39183 discloses an internal combustion engine controller capable of adjusting the fuel supply amount, ignition timing, and exhaust gas recirculation amount of the internal combustion engine. This internal combustion engine control device has an in-cylinder pressure sensor that detects the pressure in the cylinder of the internal combustion engine, and controls the fuel supply amount, ignition timing, and exhaust gas recirculation amount based on the output from the in-cylinder pressure sensor. Thus, the combustion state of the internal combustion engine is controlled.
[0003]
[Problems to be solved by the invention]
By the way, since the fuel consumption and output of the internal combustion engine can be improved by suppressing variations in the in-cylinder pressure (average effective pressure) between the cylinders of the internal combustion engine, the output of the in-cylinder pressure sensor as described above is used. It was considered to control the fuel supply amount, ignition timing, and exhaust gas recirculation amount so as to suppress variations in the in-cylinder pressure between the cylinders of the engine.
However, no specific technique has been developed on how to control the fuel supply amount, the ignition timing, and the exhaust gas recirculation amount in order to suppress variations in the in-cylinder pressure between the cylinders of the internal combustion engine.
[0004]
Accordingly, an object of the present invention is to optimally control the fuel supply amount, the ignition timing, and the exhaust gas recirculation amount to suppress the variation in the in-cylinder pressure between the cylinders of the internal combustion engine, and as a result, improve the fuel consumption and output. An internal combustion engine control device that can be provided.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, an internal combustion engine control apparatus according to the present invention comprises a fuel control means (for example, a fuel control unit 45 in an embodiment of the invention) for controlling the fuel supply amount of an internal combustion engine for each cylinder, and the internal combustion engine. Ignition timing control means for controlling the ignition timing of each cylinder (for example, the ignition timing control unit 46 in the embodiment of the invention) and EGR control means for controlling the exhaust gas recirculation amount of the internal combustion engine for each cylinder (for example, An EGR control unit 47) in the embodiment of the invention, an in-cylinder pressure sensor (for example, in-cylinder pressure sensors 38a to 38d in the embodiment of the invention) that detects the pressure in each cylinder of the internal combustion engine for each cylinder, and the EGR When the exhaust gas recirculation amount for all the cylinders by the control means is 0, the fuel for all the cylinders whose in-cylinder pressure detected by the in-cylinder pressure sensor is outside the allowable range for fuel supply. The control data of the fuel supply amount by the control means is corrected so that the in-cylinder pressure falls within the allowable range for fuel supply, and the fact that the in-cylinder pressure of all cylinders is within the allowable range for fuel supply by the correction is described above. When detected by the in-cylinder pressure sensor, the in-cylinder pressure indicates the ignition timing control data by the ignition timing control means for all cylinders for which the in-cylinder pressure detected by the in-cylinder pressure sensor is outside the allowable range for ignition timing. Supply amount / ignition timing adjusting means (for example, the fuel supply amount / ignition timing adjusting unit 49 in the embodiment of the invention) and the fuel supply amount by the fuel supply amount / ignition timing adjusting means When the in-cylinder pressure sensor detects that the in-cylinder pressures of all the cylinders are within the allowable range for the ignition timing by correcting the control data for the ignition timing, the EG Exhaust gas recirculation is generated by the control means, and the control data of the exhaust gas recirculation amount by the EGR control means for all the cylinders whose in-cylinder pressure detected by the in-cylinder pressure sensor is outside the allowable range for EGR. EGR adjustment means (for example, the EGR adjustment unit 50 in the embodiment of the invention) for correcting to be within the allowable range for use.
[0006]
First, when the fuel supply amount / ignition timing adjusting means has zero exhaust gas recirculation amounts for all cylinders by the EGR control means, the cylinder pressure detected by the cylinder pressure sensor is all outside the fuel supply allowable range. The control data of the fuel supply amount by the fuel control means is corrected so that the in-cylinder pressure falls within the allowable range for fuel supply. In this way, the fuel supply amount is adjusted in a state where the influence of the exhaust gas recirculation amount is eliminated, and variation in the in-cylinder pressure between the cylinders due to the fuel supply amount is suppressed.
[0007]
Next, the fuel supply amount / ignition timing adjusting means detects the in-cylinder pressure detected by the in-cylinder pressure sensor when the in-cylinder pressure sensor detects that the in-cylinder pressures of all the cylinders are within the allowable range for fuel supply. Is corrected so that the in-cylinder pressure falls within the allowable range for ignition timing, for all the cylinders that are outside the allowable range for ignition timing. In this way, the ignition timing is adjusted in a state where the influence of the exhaust gas recirculation amount is eliminated and the fuel supply amount is adjusted, and variation in the in-cylinder pressure between the cylinders due to the ignition timing is suppressed.
[0008]
Next, the in-cylinder pressure sensor indicates that the in-cylinder pressures of all cylinders are within the allowable range for ignition timing by correcting the fuel supply amount and ignition timing control data by the fuel supply amount / ignition timing adjusting unit. Is detected, the exhaust gas recirculation is caused by the EGR control means, and the exhaust gas return by the EGR control means is performed for the cylinder whose in-cylinder pressure detected by the in-cylinder pressure sensor is outside the allowable range for EGR due to the occurrence of the exhaust gas recirculation. The flow rate control data is corrected so that the in-cylinder pressure falls within the allowable range for EGR. In this way, after correcting each control data of the fuel supply amount and ignition timing by the fuel supply amount / ignition timing adjusting means to make these optimum values, the control data of the exhaust gas recirculation amount by the EGR control means is adjusted, Variations in the in-cylinder pressure between the cylinders due to the exhaust gas recirculation amount are suppressed.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings.
1 and FIG. 2 show an internal combustion engine 10. Reference numeral 11 denotes an internal combustion engine body, reference numeral 12 denotes an intake pipe, and reference numeral 13 denotes an exhaust pipe. Here, the case where the internal combustion engine main body 11 has four cylinders having cylinders 11a to 11d will be described as an example.
[0010]
The intake pipe 11 includes a single pipe section 15 for taking in air, and branch pipe sections 16a to 16d branched from the pipe section 15 into four branches and connected to the corresponding ones of the cylinders of the internal combustion engine main body 11, respectively. In the pipe portion 15, an air cleaner 17 that cleans the taken-in air is provided upstream in the air flow direction, and a throttle valve 18 that adjusts the air flow rate is provided downstream from the air cleaner 17. Has been placed.
[0011]
A vacuum sensor 19 is provided downstream of the throttle valve 18 in the pipe portion 15.
Further, the branch pipe portions 16a to 16d are respectively provided with injectors 20a to 20d for supplying fuel to the internal combustion engine main body 11. In other words, the injectors 20a to 20d are provided for the respective cylinders 11a to 11d. Yes.
[0012]
The exhaust pipe 13 includes pipe parts 22a to 22d provided for the cylinders 11a to 11d, a pipe part 23 for joining opposite sides of the pipe parts 22a and 22d to the internal combustion engine body 11, and pipe parts 22b and 22c. It has the pipe part 24 which joins opposite sides with respect to the internal combustion engine main body 11, and the pipe part 25 which joins opposite sides with respect to the internal combustion engine main body 11 of the pipe parts 23 and 24 further.
[0013]
An exhaust gas recirculation device 27 that recirculates the exhaust gas is provided between the pipe portion 22 d and the branch pipe portions 16 a to 16 d of the intake pipe 12.
The exhaust gas recirculation device 27 has a recirculation pipe section 28 connected between the pipe section 22 d and the branch pipe sections 16 a to 16 d of the intake pipe 12.
The reflux pipe section 28 is divided into a pipe section 29 connected to the pipe section 22d and four pipe sections 29d of the pipe section 29 from the opposite side to the branch section 16a of the intake pipe 12 respectively. Branch pipe portions 30a to 30d connected to corresponding ones to 16d.
[0014]
Further, the exhaust gas recirculation device 27 has a pump 31 for pressure-feeding exhaust gas from the exhaust pipe 13 side to the intake pipe 12 side in the pipe portion 29, and intake air is introduced from the pump 31 to the pipe portion 22 d side. A backflow prevention valve 32 for preventing the flow of air from the pipe 12 side to the exhaust pipe 13 side is provided. Thereby, the exhaust gas is recirculated from the exhaust pipe 13 to the branch pipe portions 16 a to 16 d of the intake pipe 12 by driving the pump 31.
[0015]
Further, the exhaust gas recirculation device 27 adjusts the exhaust gas recirculation amount from the exhaust pipe 13 to the respective branch pipe portions 16a to 16d of the intake pipe 12 by adjusting the opening amounts in the respective branch pipe portions 30a to 30d. Valves 33a to 33d are provided (in other words, EGR valves 33a to 33d for adjusting the exhaust gas recirculation amount of the internal combustion engine 10 are provided for the respective cylinders 11a to 11d).
[0016]
The internal combustion engine body 11 is provided with ignition plugs 35a to 35d for igniting each cylinder 11a to 11d, and ignition devices 36a to 36d (in FIG. 2) for igniting the ignition plugs 35a to 35d. Only 36d is shown (see FIG. 3) for each spark plug 35a-35d.
[0017]
The internal combustion engine main body 11 is provided with in-cylinder pressure sensors 38a to 38d (only 38d is shown in FIG. 2, see FIG. 3) for detecting the pressures in the cylinders 11a to 11d for the respective cylinders 11a to 11d. . Here, the in-cylinder pressure sensors 38a to 38d are used as washers when the spark plugs 35a to 35d are fastened, and are made of piezoelectric elements.
Further, the internal combustion engine body 11 is provided with a rotation angle detection device 41 that detects the rotation angle of the crankshaft 40.
[0018]
The outputs of the in-cylinder pressure sensors 38a to 38d, the vacuum sensor 19 and the rotation angle detection device 41 are the control devices (internal combustion engine control devices) that individually control the injectors 20a to 20d, the ignition devices 36a to 36d, and the EGR valves 33a to 33d. 43).
[0019]
As shown in FIG. 3, the control device 43 receives the control data of the fuel supply start timing by the injectors 20a to 20d and the fuel supply time (the fuel supply amount from the detection data of the vacuum sensor 19 and the rotation angle detection device 41). Equivalent) control data, ignition timing control data of the ignition plugs 35a to 35d by the ignition devices 36a to 36d, and control data of the opening amounts of the EGR valves 33a to 33d (that is, equivalent to the exhaust gas recirculation amount). Is stored in the storage unit 44 for each cylinder. Here, the storage unit 44 is a so-called battery backup RAM in which stored contents are held by a power source that is unrelated to the power source on the vehicle side.
[0020]
Further, the control device 43 reads the fuel supply start timing and the fuel supply time control data from the storage unit 44 for each of the cylinders 11a to 11d based on the detection data of the vacuum sensor 19 and the rotation angle detection device 41, respectively. Each of the injectors 20a to 20d is individually controlled so that the fuel supply is started at this timing and fuel is supplied only during this fuel supply time (in other words, the fuel supply start timing and the fuel supply amount of the internal combustion engine 10 are controlled). A fuel control unit (fuel control means) 45 is provided for controlling each cylinder 11a to 11d.
[0021]
Further, the control device 43 reads the ignition timing control data from the storage unit 44 for each of the cylinders 11a to 11d based on the detection data of the vacuum sensor 19 and the rotation angle detection device 41, etc., and each spark plug 35a at each timing. Ignition timing control unit (ignition timing control means) 46 that individually controls the ignition devices 36a to 36d so as to ignite .about.35d (in other words, controls the ignition timing of the internal combustion engine 10 for each cylinder 11a to 11d). have.
[0022]
In addition, the control device 43 reads the control data of the opening amounts of the EGR valves 33a to 33d from the storage unit 44 for each of the cylinders 11a to 11d based on the detection data of the vacuum sensor 19 and the rotation angle detection device 41. Each EGR valve 33a to 33d is individually controlled so as to have each opening amount (in other words, the exhaust gas recirculation amount of the internal combustion engine 10 is controlled for each cylinder 11a to 11d) 47. have.
[0023]
Normally, the control device 43 uses the fuel supply start timing and the fuel supply time control data read from the storage unit 44 by the fuel control unit 45 based on the detection data of the vacuum sensor 19 and the rotation angle detection device 41. The injectors 20a to 20d are individually controlled, and the ignition timing control unit 46 individually controls the ignition devices 36a to 36d with the ignition timing control data read from the storage unit 44. Further, the EGR control unit 47 has the storage unit 44. The EGR valves 33a to 33d are individually controlled by the opening amount control data read from the above.
[0024]
In this embodiment, the control device 43 controls the fuel supply amount / ignition timing adjustment unit (fuel supply amount / fuel supply amount / fuel supply amount / fuel supply amount / fuel timing amount) for performing adjustment control for suppressing variations in the in-cylinder pressure between the cylinders 11a to 11d of the internal combustion engine body 11. Ignition timing adjusting means) 49 and EGR adjusting section (EGR adjusting means) 50.
The control contents of the adjustment control by the fuel supply amount / ignition timing adjusting unit 49 and the EGR adjusting unit 50 will be described below with reference to the flowcharts of FIGS.
[0025]
In order to perform adjustment control at a predetermined timing during operation of the internal combustion engine 10 such as immediately after the internal combustion engine 10 is started, the fuel supply amount / ignition timing adjustment unit 49 first determines whether or not it is in a steady operation state. If it is determined (step S1) and it is determined that the vehicle is not in a steady operation state, this adjustment control is not executed and the process is terminated. The steady operation state is, for example, a state in which neither the engine load nor the engine speed changes, and the other states are not in the steady operation state. Next, when in a steady operation state, the fuel supply amount / ignition timing adjustment unit 49 closes all the EGR valves 33a to 33d by the EGR control unit 47, thereby causing all the cylinders 11a to 11d by the EGR control unit 47 to close. The exhaust gas recirculation amount, ie, EGR, is set to 0 (step S2).
[0026]
Next, the fuel supply amount / ignition timing adjustment unit 49 corresponds to the control data and the fuel supply amount of the fuel supply start timing from the storage unit 44 based on the detection data of the vacuum sensor 19 and the rotation angle detection device 41 and the like. The fuel supply time control data is read for each cylinder 11a to 11d, and the ignition timing control data is read for each cylinder 11a to 11d (step S3).
[0027]
Next, the fuel supply amount / ignition timing adjustment unit 49 outputs the read control data of the fuel supply start timing and the control data of the fuel supply time for each of the cylinders 11a to 11d to the fuel control unit 45 and reads it. The ignition timing control data for each cylinder 11a to 11d is output to the ignition timing control unit 46 (step S4). Then, the fuel control unit 45 causes each of the injectors 20a to 20d to supply fuel with the control data input in this way, and the ignition timing control unit 46 uses each of the ignition devices 36a to 36d with the input control data. Ignite each of the spark plugs 35a to 35d. That is, fuel supply and ignition are performed using the control data already stored in the storage unit 44.
[0028]
In this state, the fuel supply amount / ignition timing adjustment unit 49 determines the cylinder pressure Pij (i: cylinder number (1-4), j: the average effective pressure detected by all the cylinder pressure sensors 38a to 38d). The number of cycles (1 to n)) is sampled and stored (step S5).
[0029]
Next, the fuel supply amount / ignition timing adjustment unit 49 determines whether or not a predetermined n cycle for sampling the in-cylinder pressure Pij has elapsed (step S6), and when the n cycle has not elapsed, Return to step S4. Here, for example, when the influence of noise or the like is included in part of the data, the value of n is set to a value that can be made small enough to ignore the influence of noise. Note that n cycles are detected based on detection data of the rotation angle detection device 41, for example.
[0030]
When it is determined in step S6 that n cycles have elapsed, the fuel supply amount / ignition timing adjusting unit 49 determines the overall average value * Pij that is an average value from the total value of the in-cylinder pressures Pij for all 1 to n cycles of all cylinders. Is calculated (step S7), and the cylinder average values * P1j, * P2j, which are average values for the cylinders 11a to 11d, from the total value of the in-cylinder pressures Pij for all the cylinders 11a to 11d for all 1 to n cycles. * P3j and * P4j are calculated (step S8). Further, a difference ΔPi between each cylinder average value * P1j, * P2j, * P3j, * P4j and the overall average value * Pij is calculated (step S9).
[0031]
Then, the fuel supply amount / ignition timing adjustment unit 49 compares the difference ΔPi for each of the cylinders 11a to 11d with a preset allowable value for fuel supply ΔPGF (step S10). Here, the fuel supply allowable value ΔPGF is, for example, a difference ΔPi obtained by experiment, and is almost set to a minimum value that can be adjusted by only changing the fuel supply time in the state of EGR = 0. Yes.
[0032]
In step S10, when there is a difference ΔPi that is larger than the fuel supply allowable value ΔPGF, the fuel supply amount / ignition timing adjusting unit 49 applies a predetermined correction coefficient k to the difference ΔPi for the target cylinder. A correction value Tpi is obtained (step S11). Then, for the target cylinder, the control data of the fuel supply time is corrected with this correction value Tpi, updated and stored in the storage unit 44 (step S12), and the process returns to step S3. That is, when the average value for each cylinder is larger than the overall average value, the value obtained by subtracting the correction value Tpi from the control data for the fuel supply time used during sampling so as to decrease the in-cylinder pressure is used as the new control data for the fuel supply time. The storage unit 44 is updated and stored. On the other hand, when the average value for each cylinder is smaller than the overall average value, the value obtained by adding the correction value Tpi to the control data for the fuel supply time used during sampling to increase the in-cylinder pressure is used as the new control data for the fuel supply time. The storage unit 44 is updated and stored. As a result, in the subsequent control, the latest control data that has been updated and recorded is used as the control data for the fuel supply time. Here, the correction coefficient k for calculating the correction value Tpi can suppress the variation in the in-cylinder pressure that can occur between the cylinders 11a to 11d by performing the correction to, for example, about 20% of the maximum value. Is set to a value.
[0033]
As described above, the fuel supply amount / ignition timing adjustment unit 49 detects the difference ΔPi between the cylinder average value and the overall average value of the in-cylinder pressure, which is detected by the in-cylinder pressure sensor, in other words, the cylinder supply pressure value ΔPGF. Fuel supply time (corresponding to fuel supply amount) by the fuel control unit 45 for all cylinders whose cylinder pressure average value is outside the allowable range for fuel supply (range of ± ΔPGF centered on the overall average value) The control data is corrected so that the difference ΔPi falls within the allowable value for fuel supply ΔPGF, that is, the average value for each cylinder of the in-cylinder pressure falls within the allowable range for fuel supply.
Then, the fuel supply amount / ignition timing adjustment unit 49 finally determines that the difference ΔPi larger than the fuel supply allowable value ΔPGF is not in all the cylinders 11a to 11d in step S10, that is, all the corrections described above are performed. When the in-cylinder pressure sensors 38a to 38d detect that the cylinder-by-cylinder average values of the in-cylinder pressures of the cylinders 11a to 11d are within the allowable range for fuel supply, the following steps S13 and after are executed.
[0034]
In step S13, the fuel supply amount / ignition timing adjusting unit 49 sets the difference ΔPi for each of the cylinders 11a to 11d determined to be equal to or less than the fuel supply allowable value ΔPGF in step S10 immediately before, for the preset ignition timing. Compare with the allowable value ΔPGI. Here, the ignition timing allowable value ΔPGI is, for example, a difference ΔPi obtained by experiment, and is a value that can be adjusted by changing the ignition timing while EGR = 0 and adjusted by changing the fuel supply time. Is almost set to the minimum value.
[0035]
In step S13, when there is a difference ΔPi that is larger than the ignition timing allowable value ΔPGI, the fuel supply amount / ignition timing adjustment unit 49 performs correction by multiplying the difference ΔPi by a predetermined correction coefficient k for the target cylinder. A value Ipi is obtained (step S14). Then, for the target cylinder, the ignition timing control data is corrected with the correction value Ipi, updated and stored in the storage unit 44 (step S15), and the process returns to step S3. That is, when the average value for each cylinder is larger than the overall average value, a value obtained by retarding the correction value Ipi with respect to the ignition timing control data used during sampling as the new ignition timing control data so as to lower the in-cylinder pressure. The storage unit 44 is updated and stored. On the other hand, when the average value for each cylinder is smaller than the overall average value, a value obtained by advancing the correction value Ipi with respect to the ignition timing control data used during sampling as the new ignition timing control data so as to increase the in-cylinder pressure. The storage unit 44 is updated and stored. As a result, in the subsequent control, the latest control data that has been updated and recorded is used as the control data for the ignition timing. Here, the correction coefficient k for calculating the correction value Ipi suppresses the variation in the in-cylinder pressure that may occur between the cylinders 11a to 11d by performing the correction to, for example, about 6 to 7% of the maximum value. Is set to a value that can be
[0036]
As described above, the fuel supply amount / ignition timing adjusting unit 49 is detected by all cylinders in which the difference ΔPi between the cylinder average value and the overall average value of the cylinder pressure is larger than the ignition timing allowable value ΔPGI, in other words, by the cylinder pressure sensor. The ignition timing control data by the ignition timing control unit 46 is used for the difference ΔPi for all cylinders whose average cylinder pressure value is outside the allowable ignition timing range (± ΔPGI centered on the overall average value). Is corrected so that the ignition timing allowable value ΔPGI, that is, the average value for each cylinder of the in-cylinder pressure falls within the ignition timing allowable range. Finally, in step S13, when the difference ΔPi larger than the ignition timing allowable value ΔPGI is not in all the cylinders 11a to 11d, that is, the cylinder-by-cylinder average of the in-cylinder pressures of all the cylinders 11a to 11d by the correction described above. When it is detected by the in-cylinder pressure sensors 38a to 38d that the value is within the ignition timing allowable range, the EGR adjustment unit 50 executes the following step S16 and subsequent steps.
[0037]
The EGR adjustment unit 50 obtains control data for the opening amounts (that is, the exhaust gas recirculation amount) of the EGR valves 33a to 33d from the storage unit 44 based on the detection data of the vacuum sensor 19, the rotation angle detection device 41, and the like. It is read every 11d (step S16).
[0038]
Next, the EGR adjustment unit 50 outputs control data of the opening amounts of the EGR valves 33a to 33d for the respective cylinders 11a to 11d to the EGR control unit 47 (step S17). Then, the EGR control unit 47 opens the EGR valves 33a to 33d with the control data to generate exhaust gas recirculation. That is, exhaust gas recirculation is generated with the control data already stored in the storage unit 44.
[0039]
After the exhaust gas recirculation is thus generated, the EGR adjustment unit 50 samples and stores the in-cylinder pressure Pij detected by all the in-cylinder pressure sensors 38a to 38d (step S18).
[0040]
Next, the EGR adjustment unit 50 determines whether or not a predetermined n cycle for sampling the in-cylinder pressure Pij has elapsed (step S19), and when the n cycle has not elapsed, the process returns to step S17. Here, as described above, when the influence of noise or the like is included in a part of the data, a value that can be reduced to such an extent that the influence of noise can be ignored is set as the value of n. Further, n cycles are detected based on detection data of the rotation angle detection device 41, for example.
[0041]
When it is determined in step S19 that n cycles have elapsed, the EGR adjustment unit 50 calculates the overall average value * Pij that is the average value from the total value of the in-cylinder pressures Pij for all 1 to n cycles of all the cylinders 11a to 11d. At the same time (step S20), the cylinder average values * P1j, * P2j, * P3j, which are the average values for the cylinders 11a to 11d, from the total value of the in-cylinder pressures Pij for all the cylinders 1a to 11d for the cylinders 11a to 11d. , * P4j is calculated (step S21). Further, a difference ΔPi between each cylinder average value * P1j, * P2j, * P3j, * P4j and the overall average value * Pij is calculated (step S22).
[0042]
Then, the EGR adjustment unit 50 compares the difference ΔPi for each of the cylinders 11a to 11d with a preset allowable value for EGR ΔPGE (step S23). Here, the allowable value ΔPGE for EGR is a difference ΔPi obtained by experiment, and is a minimum value that can be adjusted by changing the exhaust gas recirculation amount in a state adjusted by changing the fuel supply amount and ignition timing. The value is almost set.
[0043]
If there is a difference ΔPi that is larger than the EGR allowable value ΔPGE in step S23, the EGR adjustment unit 50 obtains a correction value Qpi obtained by multiplying the difference ΔPi by a predetermined correction coefficient k for the target cylinder (step S23). S24). Then, for the target cylinder, the control data of the EGR valve is corrected with the correction value Qpi and updated and stored in the storage unit 44 (step S25), and the process returns to step S16. That is, when the average value for each cylinder is larger than the overall average value, the correction value Qpi is increased with respect to the control data for the opening amount of the EGR valve used at the time of sampling so as to decrease the in-cylinder pressure, that is, the value obtained by increasing the EGR amount. The storage unit 44 is updated and stored as control data for the opening amount of a new EGR valve. On the other hand, when the average value for each cylinder is smaller than the overall average value, the value obtained by reducing the correction value Qpi with respect to the control data for the opening amount of the EGR valve used at the time of sampling is increased to increase the in-cylinder pressure. The storage unit 44 is updated and stored as quantity control data. As a result, in the subsequent control, the latest control data that has been updated and recorded is used as the control data for the opening amount of the EGR valve.
[0044]
As described above, the EGR adjusting unit 50 determines that the difference ΔPi between the cylinder average value and the overall average value of the in-cylinder pressure is larger than the EGR allowable value ΔPGE, in other words, the in-cylinder pressure detected by the in-cylinder pressure sensor. For all cylinders whose average value is outside the allowable range for EGR (range of ± ΔPGE centered on the overall average value), control data on the opening amount of the EGR valve (corresponding to the exhaust gas recirculation amount) by the EGR control unit 47 is provided. Therefore, the difference ΔPi is corrected so as to be within the EGR allowable value ΔPGE, that is, the average value for each cylinder of the in-cylinder pressure is within the EGR allowable range. Finally, in step S23, when the difference ΔPi that is larger than the EGR allowable value ΔPGE is no longer in all the cylinders 11a to 11d, that is, the cylinder-by-cylinder average value of the in-cylinder pressures of all the cylinders 11a to 11d by the above correction. Is detected by the in-cylinder pressure sensors 38a to 38d, the adjustment control is terminated.
[0045]
According to the control device 43 described above, first, the fuel supply amount / ignition timing adjusting unit 49 is operating the internal combustion engine 10 and the EGR control unit 47 sets the exhaust gas recirculation amount for all the cylinders 11a to 11d. After the fuel supply and ignition are performed with the existing control data at 0, the fuel control unit 45 for all the cylinders 11a to 11d whose in-cylinder pressure detected by the in-cylinder pressure sensors 38a to 38d is outside the allowable range for fuel supply. Is corrected so that the in-cylinder pressure falls within the allowable range for fuel supply. In this manner, the fuel supply amount is adjusted in a state where the influence of the exhaust gas recirculation amount is eliminated, and variations in the in-cylinder pressure between the cylinders 11a to 11d due to the fuel supply amount are suppressed.
[0046]
Next, when the in-cylinder pressure sensors 38a to 38d detect that the in-cylinder pressures of all the cylinders 11a to 11d are within the allowable range for fuel supply by the correction, the in-cylinder pressure / ignition timing adjustment unit 49 detects the in-cylinder pressure. Control data of ignition timing by the ignition timing control unit 46 for all cylinders 11a to 11d whose in-cylinder pressure detected by the sensors 38a to 38d is outside the allowable range for ignition timing so that the in-cylinder pressure falls within the allowable range for ignition timing. to correct. Thus, the ignition timing is adjusted in a state where the influence of the exhaust gas recirculation amount is eliminated and the fuel supply amount is adjusted, and variations in the in-cylinder pressure between the cylinders 11a to 11d due to the ignition timing are suppressed.
[0047]
Next, the EGR adjustment unit 50 corrects the fuel supply amount and ignition timing control data by the fuel supply amount / ignition timing adjustment unit 49 so that the in-cylinder pressures of all the cylinders 11a to 11d are within the allowable range for ignition timing. Is detected by the in-cylinder pressure sensors 38a to 38d, the exhaust gas recirculation is caused by the EGR control unit 47 based on the existing control data, and the in-cylinder pressures detected by the in-cylinder pressure sensors 38a to 38d after the occurrence of the exhaust gas recirculation. Is corrected so that the in-cylinder pressure is within the allowable range for EGR, with respect to the cylinders 11a to 11d that are outside the allowable range for EGR. In this way, after adjusting the fuel supply amount and ignition timing control data by the fuel supply amount / ignition timing adjustment unit 49 to obtain optimum values, the EGR control unit 47 adjusts the exhaust gas recirculation amount control data. Thus, variations in the in-cylinder pressure between the cylinders 11a to 11d due to the exhaust gas recirculation amount are suppressed.
[0048]
As described above, the fuel supply amount, the ignition timing, and the exhaust gas recirculation amount control data are corrected in order to suppress the variation in the in-cylinder pressure between the cylinders 11a to 11d of the internal combustion engine 10, thereby improving the fuel consumption and the output. Can be made.
[0049]
In the above, the case where the exhaust gas recirculation device 27 has the pump 31 for pumping the exhaust gas has been described as an example. However, the suction pipe 12 is not provided and the suction pipe 12 is sucked with the negative pressure. You may make it make it.
In the above description, the case where the exhaust gas recirculation amount is forcibly set to 0 has been described as an example. However, if the adjustment control is performed at the timing when the exhaust gas recirculation amount becomes zero, the exhaust gas recirculation amount is forcibly set. Step S2 for setting to 0 is not necessary.
[0050]
【The invention's effect】
As described above in detail, according to the internal combustion engine control device of the present invention, the control data of the fuel supply amount, the ignition timing, and the exhaust gas recirculation amount are corrected in order to adjust the in-cylinder pressure between the cylinders of the internal combustion engine. By suppressing variation, fuel consumption and output can be improved.
[Brief description of the drawings]
FIG. 1 is a plan view schematically showing an internal combustion engine controlled by an internal combustion engine control apparatus according to an embodiment of the present invention.
FIG. 2 is a side view schematically showing an internal combustion engine controlled by the internal combustion engine control apparatus according to the embodiment of the present invention.
FIG. 3 is a block diagram showing an internal combustion engine control device and the like according to one embodiment of the present invention.
FIG. 4 is a flowchart showing a part of control contents of the internal combustion engine control apparatus according to the embodiment of the present invention.
FIG. 5 is a flowchart showing another part of the control content of the internal combustion engine control apparatus according to the embodiment of the present invention.
[Explanation of symbols]
10 Internal combustion engine
11a to 11d storage unit
38a-38d In-cylinder pressure sensor
43 Controller (Internal combustion engine controller)
44 storage
45 Fuel control unit (fuel control means)
46 Ignition timing control unit (ignition timing control means)
47 EGR control unit (EGR control means)
49 Fuel supply amount / ignition timing adjustment means (fuel supply amount / ignition timing adjustment unit)
50 EGR adjuster (EGR adjuster)

Claims (1)

Fuel control means for controlling the fuel supply amount of the internal combustion engine for each cylinder;
Ignition timing control means for controlling the ignition timing of the internal combustion engine for each cylinder;
EGR control means for controlling the exhaust gas recirculation amount of the internal combustion engine for each cylinder;
An in-cylinder pressure sensor for detecting the pressure in the cylinder of the internal combustion engine for each cylinder;
When the exhaust gas recirculation amount for all cylinders by the EGR control means is 0, the fuel supply amount by the fuel control means for all cylinders whose in-cylinder pressure detected by the in-cylinder pressure sensor is outside the allowable range for fuel supply. The control data is corrected so that the in-cylinder pressure falls within the permissible range for fuel supply, and the in-cylinder pressure sensor detects that the in-cylinder pressure of all cylinders falls within the permissible range for fuel supply. Control data of ignition timing by the ignition timing control means for all cylinders whose in-cylinder pressure detected by the in-cylinder pressure sensor is outside the allowable range for ignition timing, so that the in-cylinder pressure falls within the allowable range for ignition timing. Fuel supply amount / ignition timing adjusting means to be corrected;
When the in-cylinder pressure sensor detects that the in-cylinder pressures of all cylinders are within the allowable range for ignition timing by correcting the fuel supply amount and ignition timing control data by the fuel supply amount / ignition timing adjusting means. The EGR control means generates exhaust gas recirculation and the control data of the exhaust gas recirculation amount by the EGR control means for all cylinders whose in-cylinder pressure detected by the in-cylinder pressure sensor is outside the allowable range for EGR. EGR adjusting means for correcting the EGR to be within the allowable range for EGR;
An internal combustion engine control device comprising:

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