JPH1136940A - Control device for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To optimumly control fuel injection for every engine cylinder of an engine in which a fuel supply volume is set for every engine cylinder so as to control fuel injection for every engine cylinder, by suitably compensating unevenness in fuel injection volume caused by different characteristics of injectors. SOLUTION: An intake air volume Q for each engine cylinder 2 is calculated from an intake air volume detected by an intake air volume sensor 11 provided in an manifold intake air passage 10 of an engine 1, and a desired angular speed variation ΔΩo for every engine cylinder 2 in accordance with an operating condition of the engine is computed from the intake air volume Q for the engine cylinder 2 so as to compensate a fuel injection volume Qfj for the engine cylinder 2 in order to make an actual angular speed variation ΔΘt equal to the desired angular speed variation Δωo. Thereby it is possible to appropriately set the fuel injection volume Qfj for each engine cylinder 2 in the engine 1 with no affection by an intake air volume.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine control device, and more particularly to a technical field in which individual control is performed for each cylinder of the engine.

[0002]

2. Description of the Related Art Conventionally, as a control device for controlling each cylinder of an engine as described above, for example, Japanese Patent Application Laid-Open No.
As shown in Japanese Patent No. 322, an exhaust gas recirculation passage for recirculating a part of the exhaust gas of the engine to the intake system is connected to an independent intake passage for each cylinder, and an intake air amount for each cylinder is detected.
There is known an engine in which the exhaust gas recirculation amount is controlled for each cylinder in accordance with the intake air amount.

In addition, when fuel is supplied to each cylinder of the engine, the fuel supply for each cylinder is caused by a difference in injectors (fuel injection valves), a variation in a fuel injection pump, a variation in an intake passage, and the like. Since the difference (unequal amount) occurs in the amount and unpleasant vibration occurs during idle operation, etc.,
In order to reduce this vibration, conventionally, for example, Japanese Unexamined Patent Application Publication No. 9-7
As disclosed in Japanese Patent Application Laid-Open No. 9073, a proposal is made to detect a torque fluctuation for each cylinder of an engine and correct the fuel supply amount with respect to the intake air amount for each cylinder so that the torque fluctuation falls within a predetermined range. Have been.

[0004]

However, when fuel is supplied to each cylinder of the engine as described above, it is only necessary to correct the fuel supply amount with respect to the intake air amount for each cylinder of the engine as in the above proposed example. However, the optimal control of the fuel supply amount for each cylinder is insufficient, and there is room for improvement.

[0005] The present invention has been made in view of the above points, and an object of the present invention is to perform control for each cylinder by setting a control amount such as a fuel supply amount for each cylinder of an engine as described above.
An object of the present invention is to improve the control amount correction mode so that the control amount for each cylinder is appropriately corrected, and the optimal control for each cylinder is favorably performed.

[0006]

In order to achieve the above object, according to the present invention, an intake air amount for each cylinder of an engine is determined, and a target torque for each cylinder of the engine is set based on the intake air amount. The control amount for each cylinder is corrected so that the generated torque becomes the target torque.

More specifically, according to the first aspect of the present invention, as shown in FIG. 1, a control amount setting means for setting a control amount for at least a predetermined cylinder 2 among a plurality of cylinders 2, 2,. 21, a torque detecting means 22 for detecting the torque of the engine 1 generated by the predetermined cylinder 2, and a collecting portion 10 of the intake passage 8 to the plurality of cylinders 2, 2,. One intake air amount detecting means 1
1, an air amount calculating means 23 for calculating the amount of intake air taken into the predetermined cylinder 2 based on the detected air amount of the intake air amount detecting means 11, and a predetermined cylinder calculated by the air amount calculating means 23. Target torque calculating means 24 for calculating a target torque according to the operating state of the engine 1 based on the amount of air taken into the engine 2; and the generated torque of the predetermined cylinder 2 detected by the torque detecting means 22 is used as the target torque calculating means. And a correcting means 25 for correcting the control amount of the control amount setting means 21 so that the target torque is obtained by the control means 24.

According to this configuration, the collecting portion 1 of the intake passage 8
The intake air amount is detected by one intake air amount detecting means 11 provided for the engine 0, and based on the detected intake air amount, a predetermined cylinder 2 (for example, one cylinder) of all the cylinders of the engine 1 is transmitted. An intake air amount is calculated. Further, the torque of the engine 1 generated by the predetermined cylinder 2 is detected by the torque detecting means 22. The target torque calculating means 24 calculates a target torque corresponding to the operating state of the engine 1 based on the calculated intake air amount to the predetermined cylinder 2, and the correction means 25 detects the target torque by the torque detecting means 22. The control amount of the control amount setting means 21 is corrected so that the generated torque of the predetermined cylinder 2 becomes the target torque. As described above, the control amount of the predetermined cylinder 2 is corrected such that the target torque corresponding to the intake air amount of the predetermined cylinder 2 of the engine 1 and the torque generated by the predetermined cylinder 2 are corrected. With a simple configuration, the control amount for the second cylinder 2 is properly corrected without being affected by cylinders other than the predetermined cylinder, and optimal control of the control amount for the predetermined cylinder 2 can be performed.

According to the second aspect of the present invention, all of the plurality of cylinders of the engine are targeted. That is, in the present invention, the control amount setting means 21 sets the control amount for each cylinder 2 among the plurality of cylinders 2, 2,.
, A torque detecting means 22 for detecting the torque of the engine 1 generated for each of the cylinders 2 and a collecting portion 10 of the intake passage 8 to the plurality of cylinders 2, 2,. One intake air amount detecting means 11 and each of the cylinders 2
The amount of intake air taken in each time is determined by the intake air amount detecting means 1.
Air amount calculating means 23 for calculating based on the detected air amount
And each cylinder 2 calculated by the air amount calculating means 23
A target torque calculating means 24 for calculating a target torque according to the operating state of the engine 1 based on the intake air amount for each case;
The control amount setting means 21 such that the generated torque of each cylinder 2 detected by the torque detecting means 22 becomes the target torque of each cylinder 2 by the target torque calculating means 24.
And a correction means 25 for correcting the control amount of the above. According to this invention, the same operation and effect as the first aspect of the invention can be obtained.

According to the third aspect of the present invention, the control amount is a fuel supply amount to the cylinder 2. This allows the amount of fuel supplied to the predetermined cylinder 2 of the engine 1 to be appropriately controlled in the same manner as in the first aspect of the invention.

According to the fourth aspect of the present invention, the exhaust gas recirculation means 13 for recirculating a part of the exhaust gas of the engine 1 to the intake passage 8 is provided. Is less than the set value and the air-fuel ratio, that is, the fresh air amount (excluding the exhaust gas recirculation amount of the total intake air intake to the combustion chamber, for example, upstream of the intake port of the exhaust gas recirculation passage) Amount detected in the intake passage of
Is set so that a value obtained by dividing by the fuel amount becomes a small predetermined value. Thus, although the introduction ratio of the exhaust gas recirculation gas in the total intake air amount in each cylinder 2 of the engine 1 varies depending on the shape of the intake system, the introduction position of the exhaust gas recirculation means 13, etc. ,..., The amount of recirculation of exhaust gas in the cylinder 2 can be maintained to the maximum by the amount corresponding to the appropriate control of the predetermined cylinder 2 or each cylinder 2 to reduce not only particulates in exhaust gas but also NOx. .

[0012]

FIG. 9 shows an overall configuration of an embodiment of the present invention. Reference numeral 1 denotes an in-line four-cylinder diesel engine having four cylinders 2, 2,... It is connected to. Reference numeral 3 denotes an injector for directly injecting fuel into the combustion chamber in each of the cylinders 2. Each injector 3 is connected to one fuel injection pump 5 via a fuel supply pipe 4, and is fed from the fuel pump 5 by pressure. The fuel thus injected is directly supplied to the combustion chamber in the cylinder 2 by opening the valve of each injector 3.

Reference numeral 8 denotes an intake passage for supplying intake air (intake) to each cylinder 2 of the engine 1.
Are provided with four independent intake passages 9, 9,... Having a downstream end communicating with each cylinder 2, and one collective intake passage 10 having a downstream end connected to the upstream end of the independent intake passages 9, 9,. One intake air amount sensor 11 for detecting the amount of intake air to the engine 1 is provided in the collective intake passage 10. The intake air amount sensor 11 is, for example, an air flow sensor of a hot film type, and reacts not only to a normal flow toward the downstream side (each cylinder 2 side) but also to a reverse flow toward the upstream side of the intake air flow. These are to be detected.

Reference numeral 12 denotes an exhaust passage for discharging exhaust gas from each cylinder 2 of the engine 1. Reference numeral 13 denotes an exhaust gas recirculation device for recirculating a part of the exhaust gas in the exhaust passage 12 to the intake passage 8. The device 13 includes an exhaust gas recirculation passage 14 whose upstream end is branched and connected to the exhaust passage 12. The downstream end of the exhaust gas recirculation passage 14 is connected to the collective intake passage 10 on the downstream side of the intake air amount sensor 11,
An exhaust gas recirculation control valve 15 for adjusting the amount of exhaust gas recirculated is provided in the middle of the process. Since the exhaust gas recirculation passage 14 is connected to the intake passage 8 on the downstream side of the intake air amount sensor 11, the intake air amount sensor 11 is not deteriorated by the exhaust gas recirculation gas.

Each of the injectors 3, the fuel injection pump 5, and the exhaust gas recirculation control valve 15 are configured to operate according to a control signal from a controller 17. The controller 17 outputs an output signal of the intake air amount sensor 11, an output signal of a crank angle sensor 18 for detecting a crank angle associated with the rotation of the crankshaft 1a of the engine 1, and an accelerator opening by an accelerator pedal (not shown). At least the output signal of the accelerator opening sensor 19 for detecting the degree α is input.

The controller 17 corrects the fuel injection characteristics of each injector 3 based on the crank angular velocity fluctuations of the engine 1 with reference to FIGS. 2 to 4, and the operation of the exhaust gas recirculation control unit 13 for controlling the exhaust gas recirculation. Will be described with reference to FIG. First, the operation of correcting the fuel injection characteristics of the injector 3 (see FIGS. 2 to 4)
, In the first step S1, the engine 1
Of the four cylinders 2, 2,..., The number i of the cylinder 2 in the intake stroke (intake stroke cylinder number) is set to i = 1 (first cylinder), and in step S2, the intake stroke cylinder number i is taken into the cylinder 2 The air amount Q is set to Q = 0, and the maximum value Ωmax and the minimum value Ωmin of the angular velocity variation Ω are set to Ωmax = Ωmin =
Set to 0 respectively. In the next step S3, it is determined whether or not the exhaust gas recirculation amount (EGR amount) is larger than a set value k. If this determination is NO in "EGR amount ≤ k", the process directly proceeds to step S5. On the other hand, in step S3, "E
When "GR amount>k" is determined as YES, it is determined in step S4 whether both the engine speed Ne and the accelerator opening α are at steady values, and this determination is NO.
Returns to step S2 when, but proceeds to step S5 when the determination is YES. In other words, when the exhaust gas recirculation amount is large, the angular velocity fluctuation of the engine 1 is large. Therefore, the fuel injection characteristic of each injector 3 is corrected only when the engine speed Ne and the accelerator opening α are each at a steady value. Like that.

For the cylinder 2 of the intake stroke cylinder number i, 2
The number j (expansion stroke cylinder number) of the cylinder 2 in the expansion stroke after the stroke is determined as j = i-2. Then, step S
In step 6, it is determined whether or not the expansion stroke cylinder number j is j <1.
In the case of S, in step S7, the expansion stroke cylinder number j
Is changed to j = j + 4, and then the process proceeds to step S8. The processes in steps S6 and S7 are performed, for example, when the intake stroke cylinder number i is i = 1 and the first cylinder is in the intake stroke.
Since the cylinder number cannot be determined because the expansion stroke cylinder number j is j = i−2 = −1, by adding the number of cylinders 4, the expansion stroke cylinder number j becomes j = 3 and the cylinder 2 in the expansion stroke becomes j = −. 1
Is determined to be the same as the third cylinder.

In step S8, it is determined whether or not the intake stroke of the cylinder 2 having the intake stroke cylinder number i has started. If the determination is YES, the process proceeds to the next step S9. In step S9, the crank angle sensor 18
Is determined, for example, by 0.1 °, and if the determination is YES, the process proceeds to the next step S10. In this step S10, the intake air amount qa per crank angle of 0.1 ° is detected based on the signal of the intake air amount sensor 11, and in the next step S11, the intake air amount Q is calculated as Q = Update to Q + qa. Then, in step S12, the engine speed N
After detecting the angular velocity variation Ω of the crank angle of the engine 1 in the next step S13 shown in FIG. 3, in steps S14 to S17, the cylinder 2 of the intake stroke cylinder number i is detected.
The minimum value Ωmin and the maximum value Ωmax of the angular velocity fluctuation Ω during a period M (see FIG. 6) from the start to the end of the intake stroke of the intake stroke are calculated. Specifically, first, the angular velocity fluctuation Ω detected in step S14 and its previous minimum value Ωmin
When Ωmin ≦ Ω is NO, and when Ωmin> Ω is YES, the angular velocity variation Ω is reduced to the minimum value Ωm in step S15.
After “in”, the process proceeds to step S16. In this step S16, this time the angular velocity fluctuation Ω and the maximum value Ωma
The magnitude of the angular velocity variation Ω is determined as the maximum value Ωm in step S17 when Ωmax ≧ Ω is NO and when Ωmax <Ω is YES.
After setting ax, the process proceeds to step S18.

In step S18, it is determined whether or not the cylinder 2 having the expansion stroke cylinder number j has reached the fuel injection timing. If the determination is NO, the process returns to step S9 and repeats steps S9, S10,. That is, by repeating steps S9 to S18, in step S11, the intake air amount Q (the area of the hatched portion shown in FIG. 6A) during the intake stroke in the cylinder 2 of the intake stroke cylinder number i is reduced to the crank angle 0. Intake air quantity qa every 1 °
It can be calculated by adding each.

If the determination in step S18 is YES, in step S19 the engine rotation speed Ne and the crank angle 0.1 ° of the expansion stroke cylinder number j are stored in the fuel injection amount map table for the cylinder 2 having the expansion stroke cylinder number j.
And input a corresponding intake air amount Qtj, and read a corresponding fuel injection amount Qfj. The above crank angle 0.
An initial value is set for the intake air amount Qtj per degree, but is thereafter stored sequentially. Thereafter, step S2
0, the fuel injection amount Qfj is injected from the injector 3 of the cylinder 2 having the expansion stroke cylinder number j into the cylinder 2, and then the process proceeds to step S 21. In this step S21, it is determined whether or not the intake stroke of the cylinder 2 of the intake stroke cylinder number i has been completed. If this determination is NO, the process returns to the step S9 and repeats the steps S10, S11,.

If the determination in step S21 is YES, in step S22 shown in FIG. 4, the crank angle 0.1 for the cylinder 2 of the intake stroke cylinder number i is determined based on the intake air amount Q obtained in step S11. Calculate the intake air amount Qt per ° (= Q / 1800) and calculate it as Qt
i (= Qt) is stored in the intake air amount memory of the cylinder 2 of the intake stroke cylinder number i, and the intake air amount Qt per crank angle of 0.1 ° for the cylinder 2 of the expansion stroke cylinder number j is stored in the memory. Is read from another address and Qt = Qtj. In step S22, the angular velocity variation maximum value Ωmax is further reduced to the minimum value Ωmi.
By subtracting n, the angular velocity fluctuation value ΔΩj (= Ωmax−Ωmin) of the cylinder 2 having the expansion stroke cylinder number j is calculated. In the next step S23, the calculated angular velocity fluctuation value ΔΩj is set to the actual angular velocity fluctuation value ΔΩt. In step S24, the engine speed Ne and the intake air amount Qt are input to a preset data table. And the corresponding target angular velocity fluctuation value ΔΩo corresponding to the target torque is read. In this data table, as shown in FIGS. 5A and 5B, the target angular velocity variation value ΔΩo decreases proportionally as the engine speed Ne increases, and as the intake air amount Qt increases. Is set to increase proportionally. Next, the process proceeds to step S25, in which a value obtained by subtracting the actual angular velocity variation ΔΩt from the target angular velocity variation ΔΩo is multiplied by a gain K and added to the fuel injection amount Qfj (Δ
Ωo−ΔΩt) · K + Qfj is replaced with a new fuel injection amount Qfj.
And That is, the previous fuel injection amount Qfj is set to the target value Δ of the actual angular velocity fluctuation value ΔΩt of the cylinder 2 having the expansion stroke cylinder number j.
Correction is made according to the deviation from Ωo. And step S
In 26, the fuel injection amount map table of the cylinder 2 having the expansion stroke cylinder number j corresponds to the engine speed Ne and the intake air amount Qtj per 0.1 ° of the crank angle of the cylinder 2 having the expansion stroke cylinder number j. The corrected new fuel injection amount Qfj is written in the data location. Further, in step S27, the intake stroke cylinder number i is updated to i = i + 1, and in step S28, the intake stroke cylinder number i is updated.
Is determined to be i> 4. This determination is NO for i ≦ 4
When i> 4, i = 1 is set in step S29, and the process returns to step S2.

On the other hand, the exhaust gas recirculation device 1 shown in FIG.
In the operation of the exhaust gas recirculation control by the step S3, the first step S3
1, the engine speed Ne and the accelerator opening α are read, and in the next step S32, the engine speed Ne and the accelerator opening α are stored in the exhaust gas recirculation amount map table.
Is input, and the corresponding exhaust gas recirculation amount is read and set. Thereafter, in step S33, the opening degree of the exhaust gas recirculation control valve 15 is controlled so that the exhaust gas recirculation amount is recirculated to the intake passage 8 via the exhaust gas recirculation passage 14, and the process returns thereafter. When the exhaust gas recirculation amount is set, the same target air-fuel ratio is set for all the cylinders 2, 2,.
Each time, the exhaust gas recirculation amount is controlled so as to achieve the target air-fuel ratio in accordance with the intake air amount.

In this embodiment, the fuel injection amount map table (steps S19 and S26) used in the operation of correcting the fuel injection characteristics of the injector 3 is performed.
As shown in FIG. 8, each of the fuel injection amount Qfj of FIG. 8) and the exhaust gas recirculation amount of the exhaust gas recirculation amount map table (see step S32) used in the exhaust gas recirculation control operation, as shown in FIG. In the characteristic indicating the relationship between the amount of particulates generated in the exhaust gas and the change in the amount of particulates divided by the amount of fuel divided by the amount of fuel, the amount of generated particulates in the exhaust gas is equal to or less than the set value A1 and the air-fuel ratio A / F is small. The respective values are set so as to be the predetermined value A, specifically, the value A of the air-fuel ratio A / F immediately before the particulate generation amount sharply increases as the air-fuel ratio A / F decreases.

In this embodiment, the fuel injection amount setting means 21 (control amount) for setting the fuel injection amount Qfj for each of the four cylinders 2, 2,... Setting means).

Further, steps S13 to S17, S2
2, the engine 1 generated by each cylinder 2 by S23
Torque detecting means 22 for detecting the torque of the crank angle as the angular velocity variation value ΔΩt of the crank angle.

In steps S9 to S11, the intake air amount Q to be taken into each cylinder 2 is determined by the intake air amount sensor 11.
The air amount calculating means 23 for calculating based on the detected air amount is configured.

Further, in step S24, based on the intake air amount Q to each cylinder 2 calculated by the air amount calculating means 23, a target torque (a target angular speed variation value of the crank angle) corresponding to the operating state of the engine 1 is obtained. A target torque calculating means 24 for calculating ΔΩo) is configured.

Further, in steps S25 and S26, the fuel injection of the fuel injection amount setting means 21 is performed so that the generated torque of each cylinder 2 detected by the torque detecting means 22 becomes the target torque by the target torque calculating means 24. Correction means 25 for correcting the quantity Qfj is provided.

Therefore, in this embodiment, when each cylinder 2 of the engine 1 enters the intake stroke, the intake air is supplied to the combustion chamber in the cylinder 2 through the intake passage 8 in the same manner as in the operation of a normal diesel engine. When the cylinder 2 proceeds to the next compression stroke, air is compressed in the cylinder 2. At the injection timing before the cylinder 2 proceeds to the expansion stroke, fuel is injected from the injector 3 into the combustion chamber in the cylinder 2 and burns, and the exhaust gas generated by the combustion is exhausted from the cylinder 2 in the exhaust stroke. It is discharged through the passage 12.

At this time, in the intake stroke of each cylinder 2 of the engine 1, the intake air amount Q from the start to the end of the intake stroke of the cylinder 2 is detected by one intake air amount sensor 11 of the collective intake passage 10. It is calculated based on the intake air amount. When the cylinder 2 in the intake stroke proceeds to the expansion stroke through the compression stroke, the cylinder 2 in the expansion stroke
The fuel injection amount Qfj for (expansion stroke cylinder number j) is read from the fuel injection amount map table based on the engine speed Ne and the intake air amount Qtj, and the fuel injection amount Qfj is injected from the injector 3 into the cylinder 2. Is done. Then, the angular velocity variation Ω of the crank angle during the expansion stroke is detected, and the angular velocity variation Ω during the period M of the expansion stroke is detected.
The actual angular velocity fluctuation value ΔΩt (generated torque) is calculated from the difference between the maximum value Ωmax and the minimum value Ωmin. On the other hand, the engine speed Ne and the intake air amount Qt are input to a preset data table of the target angular velocity variation ΔΩo, and the corresponding target angular velocity variation ΔΩo (target torque) is obtained. The fluctuation value ΔΩo is compared with the actual angular velocity fluctuation value ΔΩt, and the fuel injection amount Qfj in the fuel injection amount map table is corrected by a predetermined gain K so that the actual angular velocity fluctuation value ΔΩt matches the target angular velocity fluctuation value ΔΩo. Can be rewritten. As described above, the target angular velocity fluctuation value ΔΩo corresponding to the intake air amount Qt of each cylinder 2 of the engine 1 is changed to the actual angular velocity fluctuation value ΔΩ of the cylinder 2.
The fuel injection amount Qfj for the cylinder 2 is corrected so that t coincides with each other.
Of the fuel injection characteristic fj for another cylinder 2 even if the fuel injection characteristics of the
Is properly corrected without being affected by the intake air amount. Therefore, optimal control of the fuel injection amount Qfj for the cylinder 2 can be performed. In particular, in this embodiment,
The above effect is effective because the diesel engine 1 is injected with a relatively high pressure to supply fuel and the fuel supply amount of each cylinder 2 varies greatly.

Further, since the fuel injection amount Qfj of each cylinder 2 of the engine 1 is properly performed regardless of the variation of the fuel injection characteristics of the injector 3, the exhaust gas recirculation amount map table used in the exhaust gas recirculation control operation is used. As shown in FIG. 8, even if the exhaust gas recirculation amount is set such that the particulate generation amount in the exhaust gas becomes a predetermined air-fuel ratio A that increases to a predetermined value A1 or more, By properly performing the fuel injection control of the cylinder 2 of the engine 1, the air-fuel ratio is always maintained stably and appropriately, and the exhaust gas recirculation amount is maintained at the maximum, and the NOx in the exhaust gas is maintained.
Can be reduced.

In the above embodiment, the fuel injection amount is corrected for each of the four cylinders 2, 2,... Of the engine 1. However, the fuel injection amount is corrected for two or more of the cylinders 2. The correction may be made.

Although the above embodiment has described the four-cylinder diesel engine 1, the present invention can of course be applied to diesel engines other than the four-cylinder engine. Further, the present invention is not limited to the diesel engine 1,
The present invention is also applicable to gasoline engines that directly inject gasoline fuel into cylinders and other types of engines. Further, in the above embodiment, the variation in the fuel injection amount of the injector 3 with respect to the cylinder 2 of the engine 1 is corrected. However, the present invention is otherwise applicable to the case where the cylinder 2 is individually controlled. Can be applied.

[0034]

As described above, according to the first aspect of the present invention, a predetermined cylinder (all cylinders) of the engine is determined based on the intake air amount detected by one intake air amount detecting means provided in the collecting portion of the intake passage of the engine. For example, the amount of intake air to one cylinder) is calculated, and the target torque according to the operating state of the engine is calculated based on the amount of intake air to the predetermined cylinder. Thus, the control amount for the predetermined cylinder is corrected.
Further, in the invention of claim 2, the intake air amount for each cylinder of all the cylinders of the engine is calculated from the intake air amount detected by the one intake air amount detection means, and the engine air amount is calculated based on the intake air amount for each cylinder. The target torque according to the operating state is calculated, and the control amount for each cylinder is corrected so that the actual generated torque for each cylinder becomes the target torque. Therefore, according to these inventions, when the control amount is set for each predetermined cylinder or each cylinder of the engine, the control amount for that cylinder is appropriately corrected without being affected by other cylinders with a simple configuration, Optimal control for the cylinder can be performed.

According to the third aspect of the present invention, since the control amount is a fuel supply amount, the fuel supply amount for a predetermined cylinder of the engine is appropriately corrected, and the optimal control of the fuel supply amount for the predetermined cylinder is performed. It can be carried out.

According to the present invention, when the exhaust gas recirculation control is performed in addition to the correction of the control amount, the amount of the exhaust gas recirculated in the steady state is reduced to a set value or less. And the air-fuel ratio is set to be a small predetermined air-fuel ratio, so that the introduction ratio of the exhaust gas recirculation gas in the total intake amount of each cylinder of the engine differs depending on the shape of the intake system and the introduction position of the exhaust gas recirculation means. In addition, the amount of exhaust gas recirculation in that cylinder can be kept to the maximum by appropriately controlling the predetermined cylinder or each cylinder among all cylinders of the engine, so that not only particulates in exhaust gas but also NOx can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of the present invention.

FIG. 2 is a flowchart showing a front part of a correction processing operation routine for correcting a fuel injection characteristic of an injector by a crank angular speed variation of an engine in a controller according to an embodiment of the present invention.

FIG. 3 is a flowchart illustrating an intermediate portion of a correction processing operation routine.

FIG. 4 is a flowchart illustrating a rear part of a correction processing operation routine;

FIG. 5 is a diagram illustrating characteristics of a target angular velocity variation value with respect to an engine speed and an intake air amount in a data table.

FIG. 6 is a diagram illustrating characteristics of an intake air amount and angular velocity fluctuation with respect to a crank angle.

FIG. 7 is a flowchart illustrating an exhaust gas recirculation control routine performed by a controller.

FIG. 8 is a characteristic diagram showing a characteristic of a particulate generation amount with respect to a change in an air-fuel ratio.

FIG. 9 is a diagram showing an overall configuration of an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine 2 Cylinder 3 Injector 8 Intake passage 10 Collective intake passage (collection part) 11 Intake air amount sensor (intake air amount detection means) 13 Exhaust recirculation device (exhaust recirculation means) 14 Exhaust recirculation passage 15 Exhaust recirculation control valve 17 Controller 21 Fuel injection amount setting means (control amount setting means) 22 Torque detecting means 23 Air amount calculating means 24 Target torque calculating means 25 Correcting means

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI F02M 25/07 550 F02M 25/07 550R

Claims (4)

[Claims] 1. A control amount setting means for setting a control amount for at least a predetermined cylinder of a plurality of cylinders of an engine; a torque detection means for detecting an engine torque generated by the predetermined cylinder; One intake air amount detecting means provided in the collecting portion of the intake passage for detecting the amount of intake air, and calculating the amount of intake air taken into the predetermined cylinder based on the detected air amount of the intake air amount detecting means Means for calculating an amount of air to be processed, target torque calculating means for calculating a target torque corresponding to the operating state of the engine based on the amount of intake air to the predetermined cylinder calculated by the air amount calculating means, and detection by the torque detecting means Correction means for correcting the control amount of the control amount setting means so that the generated torque of the predetermined cylinder becomes the target torque by the target torque calculation means. Engine control apparatus wherein the door. 2. A control amount setting unit for setting a control amount for each of a plurality of cylinders of an engine; a torque detection unit for detecting an engine torque generated for each of the cylinders; One intake air amount detecting means provided in a collecting portion of an intake passage for detecting an intake air amount, and an intake air amount taken in for each of the cylinders based on a detected air amount of the intake air amount detecting means. Air amount calculation means for calculating the target air amount calculated by the air amount calculation means, target torque calculation means for calculating a target torque corresponding to the operating state of the engine based on the intake air amount for each cylinder, and the torque detection Correction means for correcting the control amount of the control amount setting means so that the generated torque for each cylinder detected by the means becomes the target torque for each cylinder by the target torque calculation means. Engine control apparatus wherein. 3. The engine control device according to claim 1, wherein the control amount is a fuel supply amount to the cylinder. 4. The engine control device according to claim 1, further comprising: an exhaust gas recirculation unit that recirculates a part of the exhaust gas from the engine to an intake passage, wherein the exhaust gas recirculation unit in a steady state. Is a control device for an engine, wherein the generation amount of particulates in exhaust gas is set to a predetermined value that is equal to or less than a set value and the air-fuel ratio is small.