JP2500683B2 - Engine output control device for internal combustion engine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an engine output of an internal combustion engine for controlling an engine output of an internal combustion engine by controlling an ignition timing capable of adjusting the engine output, a fuel injection amount, or the like. The present invention relates to a control device, and more particularly to an engine output control device suitable for suppressing an engine output according to a running state of a vehicle in a vehicle internal combustion engine.

[Prior Art] In recent years, in an internal combustion engine, for example, an engine that temporarily suppresses the engine output according to the operating state of the vehicle in order to improve the shift characteristics of an automatic transmission and prevent an acceleration slip that occurs during vehicle acceleration. Output control is being adopted. Further, as such engine output control, conventionally, retard control of ignition timing that delays ignition timing than usual to suppress engine output, fuel supply reduction control that suppresses engine output by reducing fuel supply amount,
Various methods have been considered, such as intake air amount suppression control that reduces the intake air amount and suppresses engine output.Of these, retardation control is often used because of its excellent response and recovery characteristics after output suppression. It is being adopted.

However, this retard control has a problem that the so-called post combustion of fuel increases due to the delay of the ignition timing, and the exhaust temperature rises. For this reason, the engine output control device that employs the retard angle control cannot frequently execute the engine output control, and the engine output can be suppressed even when the engine output needs to be suppressed, for example, when shifting the automatic transmission. May not be suppressed. In other words, if the retard control is executed frequently, the exhaust temperature rises too much, which deteriorates various parts provided in the exhaust system, such as the catalyst provided in the exhaust system to purify the exhaust. It is not possible to execute output control.

Therefore, in order to solve this problem, the applicant of the present application proposes, in Japanese Patent Application No. 60-121068, to change the execution area and control amount of the engine output control by the ignition timing control according to the cooling water temperature of the internal combustion engine. did. And according to this method,
When the engine output control is executed, the exhaust temperature rises too much, and it becomes possible to execute the engine output control to some extent even in the operating region of the internal combustion engine where the engine output control is conventionally prohibited.
It becomes possible to expand the operating range in which the engine output control can be executed.

[Problems to be Solved by the Invention] However, this method expands the feasible operation range of the engine output control by changing the execution range and the control amount of the engine output control according to the exhaust temperature. Therefore, if the exhaust gas temperature rises too much, the engine output control cannot be executed or the engine output cannot be increased or decreased by a required amount.

This problem will occur not only when the engine output control is executed by the ignition timing retard control, but also when the other control method described above is adopted. That is, for example, in order to suppress the engine output, when the fuel supply reduction control such as temporarily stopping the fuel supply is frequently performed,
After that, even if the engine output control is restored and fuel is supplied, there is a problem that the fuel mixture cannot be ignited satisfactorily, leading to misfire, and engine output control cannot be executed for each control method. There is an operating area.

Therefore, the present invention can realize a plurality of control methods individually to execute the engine output control, and when the engine output control by the control method having the best control characteristic cannot be executed, the engine is controlled by using another control method. The present invention has been made for the purpose of providing an engine output control device for an internal combustion engine capable of executing output control, and always enabling engine output control as necessary.

[Means for Solving the Problems] That is, the structure of the present invention made to solve the above problems is, for example, as shown in FIG. 1, a plurality of units capable of adjusting the engine output of a vehicle internal combustion engine M1. A plurality of control means M2a to M2n for individually controlling the controlled object and changing the engine output, an operating state detecting means M3 for detecting the operating state of the internal combustion engine M1, a detection result of the operating state detecting means M3 and the above Each control means
Based on the priority order preset for M2a ~ M2n, the selection means M4 to select the highest priority control means M2x is executable engine output control without degrading the operating state of the internal combustion engine M1, and, Judgment means M5 for judging whether it is necessary to suppress the engine output based on the running state of the vehicle, and when it is judged by the judgment means M5 that the engine output needs to be suppressed, the selecting means M4 is used. Selected control means M2x
An engine output control device for an internal combustion engine, characterized by comprising: engine output control means M6 for operating the engine output to suppress the engine output of the internal combustion engine.

The plurality of control targets controlled by the respective plurality of control means are the internal combustion engine as described in the section of the related art.
M1 ignition timing, amount of fuel supplied to internal combustion engine M1, internal combustion engine
There is the amount of air taken into M1, etc.

[Operation] In the engine output control device of the present invention thus configured,
Of the plurality of control means M2a ~ M2n, based on the operating state of the internal combustion engine M1 and the preset priority order, engine output control can be executed without deteriorating the operating state of the internal combustion engine M1 and the highest priority order. The higher control means M2x is selected.
Then, when it is determined by the determination means M5 that the engine output needs to be controlled from the running state of the vehicle, the engine output control means M6 uses the control means M2x selected by the selection means M4 to output the engine output. Suppress. Therefore, for example, in suppressing the engine output during shifting of the automatic transmission, when the engine output control by the control unit with the highest priority is executed, the operating state of the internal combustion engine deteriorates. The engine output control is executed by using the control means having a high rank, and the operating range in which the engine output control is prohibited is greatly reduced.

EXAMPLES Examples of the present invention will be described below with reference to the drawings.

FIG. 2 is a schematic configuration diagram showing an internal combustion engine with an automatic transmission and its peripheral devices to which the present invention is applied.

As shown in the figure, an output shaft 2 of an internal combustion engine 1 is provided with an automatic transmission (hereinafter, also simply referred to as ECT) 3, and each of the internal combustion engine 1 and ECT3 is an engine control computer (hereinafter, simply referred to as an engine computer). ) 5 and an automatic transmission computer (hereinafter simply referred to as ECT computer) 7.

Here, the internal combustion engine 1 first sucks air from the atmosphere, mixes fuel and air injected from the fuel injection valve 8 with each other, and introduces the mixture to the intake port 9, and an electric spark generated by the spark plug 12. Combustion material 15 that takes out the combustion energy of the air-fuel mixture ignited by
And an exhaust system 18 through which the gas after combustion is discharged through an exhaust port 17.

The intake system 10 is provided with an air cleaner 20, an air flow meter 21 for detecting the intake air amount, a throttle valve 23 for controlling the intake air amount, and a surge tank 25 for smoothing the pulsation flow of the intake air from the upstream side. Normally, the intake air volume is the same as the throttle valve 23
It is controlled by the opening of the throttle valve, but if the throttle valve 23 is fully closed (at idle), the throttle valve
It is controlled by an idle speed control valve (ISCV) 28 provided in a bypass passage 26 that bypasses 23. The intake system 10 is also provided with a throttle sensor 30 for detecting the opening of the throttle valve 23 and an intake temperature sensor 31 for detecting the temperature of intake air.

Air taken in through the intake system 10 and the fuel injection valve 8
The air-fuel mixture with the injected fuel is sucked into the combustion chamber 15, compressed by the piston 14 and then ignited. The ignition of the air-fuel mixture is performed by electric sparks generated by the ignition plug 12. The spark plug 12 provided in each cylinder of the internal combustion engine 1 is connected to a distributor 35 that distributes the high voltage generated in the igniter 33 in synchronization with the rotation of the output shaft 2 through a high voltage cord (not shown). Has been done. In the distributor 35, a cylinder discrimination sensor 36 that generates a pulse signal once for each rotation of the output shaft 2, and a rotation speed sensor 37 that outputs a pulse signal for each predetermined rotation angle of the output shaft 2.
And are provided.

The air-fuel mixture that is ignited by spark ignition and explosively burns to push down the piston 14 is then exhausted to the exhaust system 18
And then released into the atmosphere. In this exhaust system 18,
An air-fuel ratio sensor 38 for detecting the air-fuel ratio of the air-fuel mixture based on the composition of the exhaust gas, a three-way catalyst 39 for purifying the exhaust gas, an exhaust temperature sensor 40 for detecting the exhaust gas temperature, etc. are provided.

The cylinder block 41 of the internal combustion engine 1 is cooled by the circulating cooling water, and the temperature of this cooling water is detected by the water temperature sensor 43.

Next, as is well known in the art, the automatic transmission 3 controls the hydraulic pressure by energizing / de-energizing the solenoid valves 50a, 50b, 50c of the hydraulic pressure control device 50 to change the engagement state of the internal friction engagement device. By changing it, it is possible to change the speed of a plurality of stages.

Each solenoid valve 50a, 50b, 50c of the hydraulic control device 50 is driven by a control signal output from the ECT computer 7. The ECT computer 7 has a vehicle speed sensor 52 and a shift position sensor 54 provided in ECT3, a pattern select switch 56 for selecting a driving pattern such as a fuel consumption-oriented driving or a power performance-oriented traveling, and an overdrive for outputting a shift permission signal to overdrive. A drive switch 58, a brake switch 60 that detects depression of the brake pedal 59, or a detection signal from the above-described throttle sensor 30, water temperature sensor 43, or the like, and calculates a shift speed according to the running state of the vehicle,
Depending on the calculation result, each solenoid valve 50a, 5 of the hydraulic control device 50
By controlling 0b and 50c, the shift control of ECT30 is executed.

In the internal combustion engine 1, the fuel injection valve 8, the ISCV 28 and the igniter 33 are driven and controlled by the operation of the engine computer 5, so that the fuel injection amount, the ignition timing, or the engine speed during idle operation (idle speed).
Is controlled.

In the engine computer 5, in addition to the detection signals from the various sensors provided in the internal combustion engine 1, the detection signals from the vehicle speed sensor 52 and the brake switch 60 provided in the ECT 3, and the ECT computer 7 to the hydraulic control circuit 50. A control signal or the like output to the engine is input, optimal engine control is executed in accordance with the operating state of the internal combustion engine 1 detected by the above-mentioned sensors, and a shift shock that occurs during shifting of the automatic transmission 3 is softened. Lume's engine output control is executed.

Hereinafter, the engine output control executed by the engine computer 5 will be described in detail with reference to the flowcharts shown in FIGS. 3 and 4.

Note that the engine output control of the present embodiment includes ignition timing retard control for retarding the ignition timing determined by the high voltage output timing of the igniter 33 to suppress the engine output, and fuel output from the fuel injection valve 8. The fuel injection amount reduction control for reducing the injection amount to suppress the engine output is used, and when the engine output control by each control can be executed, the engine output control is executed by the ignition timing retard control. The engine output control is executed by reducing the fuel injection amount when the operation state of the internal combustion engine 1 deteriorates when the retard control is executed.

First, FIG. 3 shows an engine control amount calculation process which is repeatedly executed by the engine computer 5 and calculates the fuel injection amount and the ignition timing. The calculation result by this process is based on the detection signal from the cylinder discrimination sensor 36. A control signal output process executed in synchronization with the rotation of the internal combustion engine 1 is used to output a drive signal to the fuel injection valve 8 and the igniter 33.

As shown in the figure, when the processing of this routine is started, step 100 is executed, and the fuel injection amount (valve opening time of the fuel injection valve 8) according to the operating state of the internal combustion engine 1 is executed based on the detection signals from the above-mentioned sensors. And ignition timing (high voltage output timing of the igniter 33) are calculated. As is well known in the art, this process calculates the fuel injection amount and the ignition timing corresponding to the engine load based on the intake air amount and the engine speed detected by the air flow meter 21 and the rotation speed sensor 37, and calculates the calculation result. , Intake air temperature sensor 31, air-fuel ratio sensor 38, exhaust temperature sensor
40, correction is performed according to a detection signal from the water temperature sensor 43 and the like.

When the fuel injection amount and the ignition timing are calculated in step 100, the process proceeds to the next step 110, and it is determined whether or not the internal combustion engine 1 is currently in a state where the ignition timing retard control can be executed. In this process, if the engine output control by retarding the ignition timing is frequently performed, the exhaust temperature rises too much and the three-way catalyst 39
If the ignition timing is retarded while the internal combustion engine 1 is not sufficiently warmed up when the internal combustion engine 1 is started, for example, the various components provided in the exhaust system 18 are deteriorated. Since it may not be possible to ignite the engine and the operating state of the internal combustion engine 1 may be deteriorated, in such a case, the ignition timing retarding control is prohibited. Therefore, in this step 110, it is judged whether the exhaust temperature detected by the exhaust temperature sensor 40 is equal to or higher than a predetermined value, or the cooling water temperature or the intake air temperature sensor detected by the water temperature sensor 43.
This is realized by determining whether or not the intake air temperature detected at 31 is below a predetermined value.

In order to detect that the exhaust temperature is high, the exhaust temperature sensor 40 may be used as described above, but in an internal combustion engine that does not have an exhaust temperature sensor,
The rise in exhaust temperature may be estimated from the frequency of the retard control. Further, since the combustion temperature of the fuel mixture that retards the ignition timing rises, the retard control may be prohibited even when the internal combustion engine 1 is close to an overheat state in which the cooling water temperature becomes a predetermined value or higher. .

Then, in step 110, when it is determined that the ignition timing retard control can be executed, the process proceeds to step 120, and the ignition timing retard control is selected as the control method used when executing the engine output control in the process described later. Then, that effect is recorded in a predetermined recording area.

On the other hand, when it is determined in step 110 that the ignition timing retard control cannot be executed, step 130 is executed, and this time it is determined whether the engine output control using the fuel injection amount reduction control can be executed. . This process is also a process for preventing the deterioration of the operating state of the internal combustion engine 1 by executing the reduction control of the fuel injection amount, similar to step 110, and the internal combustion engine 1 is not sufficiently warmed up, for example. In this case, it is determined that the fuel injection amount reduction control cannot be executed. That is, similar to the ignition timing retard control, if the fuel injection amount is reduced when the internal combustion engine 1 is not sufficiently warmed up, the fuel mixture cannot be satisfactorily ignited, and the operability of the internal combustion engine 1 is reduced. Therefore, in such a case, it is determined that the engine output control by the fuel injection amount reduction control cannot be executed.

Then, in step 130, when it is determined that the engine output control by the fuel injection amount reduction control can be executed,
140, select the fuel injection amount reduction control as the control method used when executing the engine output control in the process described later,
The fact is recorded in a predetermined recording area.

On the other hand, if it is determined in step 130 that the fuel injection amount reduction control cannot be executed, that is, if neither the ignition timing retard control nor the fuel injection amount reduction control can be executed, even if the automatic transmission 3 is shifting. Even if there is, the engine output cannot be suppressed, so an engine output control prohibition signal indicating that fact is output to the ECT computer 7 side, and gear change control is executed accordingly.

Next, when the control used for the engine output control is selected and recorded in the processing of steps 110 to 140, step 160 is executed. In step 160, based on the control signal output from the ECT computer 7 to the hydraulic control device 50, it is determined whether engine output control is necessary. That is ECT
When the control signal output from the computer 7 to the hydraulic control device 50 changes, the gear position of the automatic transmission 3 is changed accordingly, and it is necessary to suppress the engine output.
Thus, it is determined whether or not the engine output control of the next step 170 is executed. And this step 16
When it is determined that the engine output control needs to be executed at 0, the engine output control of step 170 is executed, otherwise, the processing of this routine is once ended, and the above step 100 is executed again.
Move to The processing of step 160 corresponds to the determination means of the present invention.

Next, FIG. 4 shows the engine output control executed in step 170.

As shown in the figure, in the engine output control, the first step
After executing 200, the control signal to the hydraulic control device 50 is changed, and then it is confirmed that the automatic transmission 3 actually starts shifting. In other words, even if the control signal output from the ECT computer 7 to the hydraulic control device 50 is changed, it takes some time before the automatic transmission 3 actually operates and the gear shift operation is started. In this embodiment,
For example, after confirming that the shift operation by the automatic transmission 3 is actually started by a change in the engine speed detected by the rotation speed sensor 37 or the like, the process proceeds to the next step 210.

Then, in step 210, the selected control method,
That is, in order to suppress the engine output by using the ignition timing retard control or the fuel injection amount reduction control, the ignition is controlled according to the type of shift by the automatic transmission 3 and the throttle opening detected by the throttle sensor 30. The retardation amount of the timing or the reduction amount of the fuel injection amount is calculated, and the fuel injection amount or the ignition timing determined in step 110 according to the operating state of the internal combustion engine 1 is corrected. This process is repeatedly executed until it is determined in the next step 220 that the shifting operation of the automatic transmission 3 has been completed, whereby the ignition timing or the fuel injection amount of the internal combustion engine 1 is corrected in the direction of suppressing the engine output. The Rukoto.

Next, when it is determined in step 220 that the gear shifting operation of the automatic transmission 3 has ended, the routine proceeds to step 230, where engine output control return processing is executed. This process is the same as step 21 above.
By correcting the ignition timing or the fuel injection amount while gradually reducing the ignition timing retard amount or the fuel injection amount reduction amount obtained by the processing of 0, the engine output of the internal combustion engine 1 is not suddenly increased. And is repeatedly executed until the ignition timing retard amount or the fuel injection amount decrease amount becomes zero. Then, when the ignition timing or the fuel injection amount is completely restored, the engine output control is ended.

In order to determine that the gear shifting operation of the automatic transmission 3 is completed in step 220, the rotation speed sensor 37 and the vehicle speed sensor
Engine speed of internal combustion engine 1 detected by 52 and automatic transmission 3
By determining whether or not the ratio of the output shaft to the rotation speed of the output shaft matches the speed change gear ratio of the automatic transmission 3 obtained based on the control signal output from the ECT computer 7 to the hydraulic control device 50, Can be realized.

As described above, in the present embodiment, the engine computer 5 is configured to be able to execute both the engine output control by the ignition timing retard control and the engine output control by the fuel injection amount reduction control, and the engine output control is responded. When the ignition timing retarding control, which can be frequently executed, deteriorates the operating state of the internal combustion engine 1, the engine output control is executed by the fuel injection amount reduction control. Therefore, compared with the conventional device configured to execute the engine output control by only one certain method such as ignition timing retard control, the prohibited area of the engine output control is greatly reduced, and the engine output control is improved. Will be able to run.

In the above embodiment, the igniter 33 that determines the ignition timing and the fuel injection valve 8 that determines the fuel injection amount correspond to the above control means, and the various sensors described above correspond to the operating state detection means. Further, the control means shown in FIGS. 3 and 4 executed by the engine computer 5 corresponds to the selection means and the control means.

Here, in the above embodiment, the engine output control is executed by the ignition timing control and the fuel injection amount control.
As a result, the engine output control is executed by suppressing the amount of air taken into the internal combustion engine.The intake air amount control is also configured to be executed at the same time. Both ignition timing retard control and fuel injection amount reduction control are executed. If it is not possible, the engine output control may be executed by the intake air amount control. In this case, the engine output control prohibited area can be further reduced as compared with the above embodiment.

Further, in the above embodiment, the engine output control by the ignition timing control is executed with priority, but the engine output control by the fuel injection amount control may be executed by priority, and the engine output control by the intake air amount control may be executed. When it is made possible to execute, this may be executed with the highest priority.

[Effects of the Invention] As described in detail above, in the engine output control apparatus for an internal combustion engine of the present invention, the control means used for engine output control can be selected from a plurality of control means without deteriorating the operating state of the internal combustion engine. The control means that can execute the output control and has the highest priority is selected, and the engine output control is executed. As a result, the operating range where engine output control is prohibited is significantly reduced, and when the running state of the vehicle is in a state where engine output should be suppressed, such as during gear shifting of the automatic transmission or when vehicle acceleration slip occurs, The engine output can be suppressed without deteriorating the operating condition of the engine. In addition, because the operating area where engine output control is prohibited in this way can be significantly reduced,
While the vehicle is traveling, the engine output can be suppressed as needed, and the traveling stability of the vehicle can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating the configuration of the present invention, FIG. 2 is a schematic configuration diagram showing an internal combustion engine and peripheral devices of the embodiment,
FIG. 3 is a flowchart showing the engine control amount calculation processing executed by the engine control computer, and FIG. 4 is a flowchart showing the engine output control executed in step 170 thereof. M1,1 …… Internal combustion engine M2a-M2n …… Control means M3 …… Operating state detection means M4 …… Selection means M5 …… Engine output control means 3 …… Automatic transmission 5 …… Engine control computer (engine computer) 7 ... Computer for automatic transmission (ECT computer) 8 ... Fuel injection valve, 12 ... Spark plug 21 ... Air flow meter 30 ... Throttle sensor 33 ... Igniter, 37 ... Rotation speed sensor 40 ... Exhaust temperature Sensor, 43 ... Water temperature sensor

Claims (1)

(57) [Claims] 1. A plurality of control means for individually controlling a plurality of control objects capable of adjusting an engine output of an internal combustion engine for a vehicle to change the engine output, and an operating state detecting means for detecting an operating state of the internal combustion engine. Based on the detection result of the operating state detecting means and the priority order preset for each control means, the engine output control can be executed without deteriorating the operating state of the internal combustion engine, and the highest priority order is obtained. Selection means for selecting the control means, determination means for determining whether or not the engine output needs to be suppressed based on the running state of the vehicle, and determination means for determining that the engine output needs to be suppressed And an engine output control unit that operates the control unit selected by the selection unit to suppress the engine output of the internal combustion engine.