JPH04342857A - Electronic control device of internal combustion engine - Google Patents

Abstract

PURPOSE:To correctly execute fuel injection control or the like in an internal combustion engine, the intake efficiency of which is improved by using the dynamic pressure corresponding to the car velocity. CONSTITUTION:The first controlled variable is computed from the intake pressure Pm from an intake pipe pressure detecting means 12 of an engine 11 and a signal Ne from a rotating speed detecting means 14 by the first arithmetic means 20. The second controlled variable is computed from a signal Ne from the rotating speed detecting means 14 and an opening signal thetath from a throttle opening detecting means 15 by the second arithmetic means 21. In this case, the dynamic pressure P obtained corresponding to the car velocity from a dynamic pressure detecting means 19 is supplied to the second arithmetic means 21, and the correction is performed corresponding to the dynamic pressure P. The dynamic pressure P is calculated according to the reference dynamic pressure Pmo when the car velocity is 0 and the intake pressure Pm obtained by the intake pipe pressure detecting means 12. One of the above first and second controlled variables is selected to be used in controlling the engine.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] This invention relates to the number of revolutions of an internal combustion engine,
The present invention relates to an electronic control device for an internal combustion engine that uses intake air pressure and the opening degree of a throttle valve such as a throttle valve as parameters, and controls fuel supply amount, ignition timing, etc. using control data obtained based on these parameters.

0002

2. Description of the Related Art For example, as shown in Japanese Patent Application Laid-Open No. 56-96132, a control device for an engine of a two-wheeled vehicle, etc. Intake pressure Pm to
Furthermore, it is known that data corresponding to the operating condition of the engine is selected from engine operating parameters such as the engine rotational speed Ne, and electronic control of the fuel injection amount and ignition timing is executed. There is.

In this case, the engine speed data Ne and intake pressure Pm are selected in a low engine load state, and the engine speed data Ne and throttle valve opening data θth are selected in medium and high engine load states. Engine control amounts (fuel injection amount, ignition timing, etc.) stored in a map are output.

[0004] Furthermore, as a means to improve the torque and horsepower of the engine, it has been considered to open an intake duct toward the direction in which the vehicle is traveling to take in wind at the speed of the vehicle while the vehicle is running. That is, the intake efficiency is improved by the dynamic pressure P corresponding to the vehicle speed V.

However, when the intake efficiency is improved by such a dynamic pressure P, a problem arises particularly when control is performed to derive the engine control amount based on the rotational speed data Ne and the throttle valve opening data θth. That is, as the vehicle speed V increases, the vehicle speed wind increases, and the amount of intake air using this vehicle speed wind increases, improving the intake efficiency and making it possible to obtain a larger output.

As described above, even if the throttle valve opening θth is the same value, as the vehicle speed V increases, the vehicle speed wind increases and the amount of air taken into the engine changes. Despite the changes, the rotational speed Ne and the throttle valve opening θ
In the conventional method (α-N method) of determining the engine control amount based on information about th, only a constant engine control amount can be set at all times. Therefore, not only is it not possible to perform proper engine control, but even though the intake duct is set to face the direction of travel of the vehicle in order to improve intake efficiency, there is a problem that the effect cannot be fully obtained. there were.

[0007]

[Problems to be Solved by the Invention] This invention has been made in view of the above points, and it is an object of the present invention to detect the dynamic pressure P that fluctuates as the amount of intake air changes in accordance with changes in the vehicle speed V, and An electronic control device for an internal combustion engine that can always perform appropriate internal combustion engine control by setting a control amount for the internal combustion engine based on the dynamic pressure P in addition to information on the throttle valve opening θth. The purpose is to provide

[0008]

[Means for Solving the Problems] An electronic control device for an internal combustion engine according to the present invention provides an electronic control device for an internal combustion engine that determines a control amount of the internal combustion engine based on the rotational speed Ne of the internal combustion engine and the throttle valve opening θth. The device detects dynamic pressure P generated by an external action regardless of the operation of the internal combustion engine,
The control amount of the internal combustion engine is determined in consideration of this dynamic pressure P.

[0009]

[Operation] The electronic control device for an internal combustion engine constructed in this manner includes, for example, an intake duct that opens toward the direction in which the vehicle is traveling, and takes in a dynamic pressure P that corresponds to the vehicle speed. Basically, the control amount of the internal combustion engine is obtained by the internal combustion engine rotational speed Ne and the throttle valve opening θth, but especially when the vehicle is running, the dynamic pressure P depending on the vehicle speed is The dynamic pressure P is detected, and the control amount is corrected based on this dynamic pressure P. Therefore, the dynamic pressure P
In a control device designed to incorporate the above, appropriate internal combustion engine control is always executed.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the basic configuration of a control circuit section composed of a microcomputer, etc., which performs electronic control of the internal combustion engine 11. The intake pressure that takes in the detection signal from the intake pressure sensor set for the internal combustion engine 11 is shown in FIG. Pm detection means 12, cranking detection means 13 for detecting signals from a rotation angle sensor of the engine 11, rotation speed N for capturing detection signals from a rotation sensor set on the rotation shaft of the engine 11;
e detection means 14, and throttle (throttle valve) opening θth detection means 15 which takes in a detection signal from a throttle opening sensor.

[0011] Also, in this control circuit, a reference dynamic pressure retrieval means 16 is set, which is constituted by a storage device that stores a reference dynamic pressure Pmo when the vehicle speed is zero. Here, the cranking angle detecting means 13 determines whether cranking is in progress based on the starter signal, the intake pressure during cranking is detected as atmospheric pressure by the atmospheric pressure detecting means 17, and further, the atmospheric pressure is used to detect the cranking. The output from the atmospheric pressure correction means 18 that corrects the intake pressure when the pressure is "0" is supplied to the reference dynamic pressure search means 16.

[0012] In this reference dynamic pressure search means 16, for example, the throttle valve opening θth is 10° and 20°.
,..., 80° and the rotation speed Ne is 1000 rpm.
, 2000 rpm, . . . 10000 rpm, the reference dynamic pressure Pmo is stored as a map.

The reference dynamic pressure search circuit 16 is supplied with detection data of the intake pressure Pm from the intake pressure detection means 12 and the rotational speed Ne from the rotational speed detection means 14, and determines the reference dynamic pressure based on the rotational speed Ne. Search for pressure Pmo. Then, this searched reference dynamic pressure Pmo and the intake pressure Pm at that time are
The dynamic pressure detection means 19 detects the dynamic pressure P based on the difference between the two.

The signal Pm from the intake pressure detection means 12 and the detection signal Ne from the rotation speed detection means 14 are supplied to the first calculation means 20. Then, this first calculation means 2
0, the first engine control amount is calculated. Further, the detection signal Ne from the rotational speed detection means 14, the detection signal θth from the throttle opening detection means 15, and the detection signal P from the dynamic pressure detection means 19 are supplied to the second calculation means 21. Then, this second calculation means 21 calculates a second engine control amount.

First and second calculation means 20 and 21
The control amount calculated in is selected by the selection means 22 in accordance with the control status of the engine 11, and the selected control amount is supplied to the engine (internal combustion engine) control means 23 to control the fuel for the internal combustion engine 11. Used to control supply amount, ignition timing, etc.

Here, the selection means 22 selects either the first engine control amount from the first calculation means 20 or the second engine control amount from the second calculation means 21. However, it may be configured to include, for example, a gradual change means for gradually changing the first engine control amount to the second engine control amount.

FIG. 2 shows the configuration of an engine (internal combustion engine) 31 and its peripheral devices in which fuel injection control, ignition timing control, etc. are performed electronically. Intake pipe 32 of engine 31
Air containing dynamic pressure is introduced into the engine 31 , and this intake air is guided to the cylinder section of the engine 31 via an air cleaner 33 . The intake pipe 32 is provided with a throttle valve 34 operated by an accelerator pedal (not shown) to control the amount of intake air.

The engine 31 is provided with a rotation angle sensor 35 for detecting its rotational state, so that a cylinder discrimination signal and an angle signal of the engine 31 are detected, and an engine rotation speed signal Ne is detected based on this angle signal. is now in demand. Further, an intake pipe pressure sensor 36 is provided so as to communicate with the intake pipe 32, and an opening sensor 37 is provided on the throttle valve 34 to determine the intake pipe pressure Pm and the throttle valve angle θth, respectively.

The intake pipe 32 is provided with an intake temperature sensor 38 for detecting the temperature of intake air, and also a water temperature sensor 39 for detecting the temperature of the cooling water of the engine 31. and,
These intake air temperature and water temperature detection signals, as well as the detection signals from each of the sensors 35, 36, and 37, are supplied to a control device 40 consisting of an electronic control unit constituted by, for example, a microcomputer, so as to determine the appropriate fuel injection amount and The ignition timing is calculated, and based on these calculation results, a fuel injection command is given to the injector 41 provided in the intake pipe 32 portion, and an ignition command is given to the ignition plug 42.

When calculating the fuel injection amount and ignition timing, atmospheric pressure correction is performed in which the intake pressure taken in when a starter signal (not shown) is turned on is recognized as atmospheric pressure, and water temperature sensor 39, intake temperature sensor 38, etc. Correction is performed based on the detection signal from the sensor, and commands are given from the control device 40 to the injector 41 and the spark plug 42.

FIG. 3 explains the air intake part of the intake pipe 32. This intake pipe 32 is equipped with an intake duct 321 that opens toward the front of the vehicle body, and a dynamic pressure P corresponding to the traveling speed of the vehicle is taken in. It looks like this. and,
The intake air taken in through the intake duct 321 is guided to the throttle valve 34 section via the air cleaner 33, and the intake air that has passed through the throttle valve 34 section is introduced into the engine 31. By improving the intake efficiency using the dynamic pressure P in this manner, effective combustion can be obtained in the engine 31.

In the electronic control device shown in the embodiment,
Intake pressure Pm of the engine 31 and rotation speed N of the engine 31
The D-J method calculates the basic fuel injection amount based on ing.

FIG. 4A shows the rotational speed Ne of the engine 31.
The figure shows an example of changes in the intake pressure Pm and the throttle opening θth in which the load is gradually increased from an idle rotation state (low load operation) to a full load state while the engine speed is kept constant. As is clear from this figure, when the load changes from "0" to full load, the intake pressure Pm decreases exponentially, and the throttle opening θth increases almost exponentially.

In view of these considerations, in this embodiment, when the engine 31 is under low load, the intake pressure Pm
is adopted as a parameter, and the throttle opening degree θth is mainly adopted as a parameter in medium and high load conditions. By doing this, the engine 31 is controlled by using parameters that have a large rate of change with respect to load fluctuations over all operating ranges from the "0" load state to the full load state.
operation control will be performed.

[0025] Intake pressure Pm and throttle opening θth
The selection of the parameter is such that the detected value of the opening degree θth is a preset value, for example, the intake pressure Pm shown in (A) of FIG.
This is done by comparing the throttle opening degree θth with values θth1 and θth2 near the intersection F of both curves. For example, in a state where the detected value of the throttle opening θth is smaller than the set value θh1, the control amount is determined mainly according to the detected value of the intake pressure Pm, and fuel injection amount control is performed.

Furthermore, when the throttle opening θth increases and exceeds the throttle opening θth2, a control amount is determined mainly according to the detected value θth of the throttle opening, and the fuel injection amount is controlled according to this control amount. is executed.

Furthermore, when the value of the throttle opening θth is between the set values θth1 and θth2,
As shown in FIG. 4B, a value determined by weighting according to the detected value Pm of the intake pressure and the throttle opening θth is adopted as the control amount, and the engine 31 is controlled.

When the intake duct 321 of the intake pipe 32 is set to open toward the traveling direction of the vehicle as shown in FIG. 3, the absolute pressure Pm of the intake pipe 22 is determined by the dynamic pressure P when the vehicle is running. , changes as shown in FIG. 4(C). That is, the intake pipe absolute pressure Pm increases as the vehicle speed increases.

In this way, with the intake structure in which the intake duct 321 is opened toward the vehicle traveling direction, the D-J method and the α-N method can be used.
When control is performed using both methods, the control amount will deviate by the amount of increase in intake pressure due to dynamic pressure P during control using the α-N method. Therefore, in the control device shown in this embodiment, the dynamic pressure P is corrected during this α-N method control.

FIG. 5 shows the control device 3 that calculates the fuel injection amount.
2 shows the flow of processing in 0. First, step 101
Then, the opening information θth obtained by converting the detection signal from the throttle valve opening sensor 37 into a digital signal is read. In step 102, this read throttle valve opening θ
th is compared with a set value θth2. If it is determined that the detected opening degree θth exceeds the set opening degree θth2, the process proceeds to step 103 and the DJ method is used.
The weight constant K of the α-N method is set to “1” so that control is performed only using the α-N method. Also, in step 102, the detected value θth is changed to the set value θth.
If it is determined that it is smaller than 2, step 104
Then, the weighting constant K of the DJ method and the α-N method is searched, or control is performed using only the DJ method.

In step 105, the detection output signal from the pressure sensor 36 is converted into a digital signal, and the intake pressure Pm is calculated.
Load. Furthermore, in step 106, the rotational speed Ne of the engine 31 obtained based on the pulse signal generated from the rotational angle sensor 35, for example, every 180° CA.
Load.

In the next step 107, the intake pressure Pmo corresponding to the rotational speed Ne when the vehicle speed V is "0" and the dynamic pressure P is "0", which are stored in advance, is calculated based on the rotational speed Ne at that time and the throttle opening. Search the storage device based on the degree θth and read it. The intake pipe pressure Pmo when the vehicle speed is "0" is mapped to the controller 40 as described above.
It is stored in a storage device which is one of the components of.

In step 108, the intake pipe pressure Pmo taken in step 107 is corrected using the intake pressure taken in during cranking, that is, atmospheric pressure, based on the following equation. Pmo←Pmo×(intake atmospheric pressure/760)

003
4] In step 109, the pressure increase due to the dynamic pressure P is determined by the intake pipe pressure Pmo obtained in step 108 when the vehicle speed is "0" and the intake pipe pressure Pm with the dynamic pressure P added at the current vehicle speed V. minute DPm to “DPm”
= Pm - Pmo". Then,
In step 110, the pressure increase DPm due to this dynamic pressure P is
The fuel injection amount increase FRA is determined based on the following.

In step 111, the fuel injection time width Tθth·N is searched from a map of the throttle opening θth and the engine rotational speed Ne adapted in advance using α-N, that is, the throttle opening θth and the engine rotational speed Ne. Furthermore, in step 112, the fuel injection width TP/N is determined by D-J, that is, the intake pipe pressure Pm and the rotational speed Ne.
is searched from a map of intake pipe pressure Pm and rotational speed Ne adapted in advance.

In step 113, the basic fuel injection width TB
is determined by weighting α-N and D-J. Regarding α-N, weighting K and fuel injection width Tθth・searched from a map of intake pipe pressure θth and rotational speed Ne adapted in advance
It is determined from the fuel injection amount increase FRA determined from N and the pressure increase DPm due to the dynamic pressure P. Also, regarding D-J,
It is determined from the weighting K and the fuel injection width TP/N retrieved from a map of the intake pipe pressure Pm and rotational speed Ne adapted in advance.

Step 114 In step 113
The final injector driving time width TAU is determined from the basic fuel injection width TB determined in step 1, correction values β for the acceleration/deceleration state, water temperature, intake air temperature, etc., and the injector operating time γ determined from the battery voltage. Then, the next step 115
Then, the final drive time TAU determined in step 114 is output to the injector 41, and fuel is injected within that time range.

In the embodiments described above, fuel injection control was described, but similarly, ignition timing control also
It is also possible to use the α-N method and the DJ method together, and correct the region of the α-N method using the pressure increase DPm due to the dynamic pressure P.

Furthermore, in the embodiment, the control amount is set by switching between the DJ method and the α-N method depending on the engine load state;
The control amount may be set in consideration of the dynamic pressure P.

Further, in the embodiment, the dynamic pressure P is detected based on the detection result of the intake pressure sensor 36, and the control amount is set taking this dynamic pressure P into consideration. The dynamic pressure P may be determined from the intake air amount per unit time corresponding to the throttle valve opening θth and the actual intake air amount per unit time when the vehicle is running. The dynamic pressure P may be determined based on the information from the vehicle speed sensor.

[0041]

As described above, in the electronic control device for an internal combustion engine according to the present invention, the D-J method and the α-N method are used in combination, and all the Fuel injection control of the internal combustion engine is performed using parameters that have a large rate of change with respect to load fluctuations over the operating range. In this type of control, engine control using dynamic pressure P obtained as the vehicle travels is always performed accurately, and if intake efficiency is improved by using dynamic pressure P that corresponds to vehicle speed. Accurate engine control will now be performed that takes into account the dynamic pressure.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram illustrating an outline of an electronic control device for an internal combustion engine according to an embodiment of the present invention.

FIG. 2 is a diagram showing a specific configuration example of the device according to the above embodiment.

FIG. 3 is a diagram showing the intake pipe portion shown in FIG. 2 taken out;

[Figure 4] (A) shows intake pipe pressure Pm corresponding to engine load.
(B) is a diagram showing the state of the weighting constant K corresponding to the throttle valve opening θth, and (C) is a diagram showing the relationship between intake pipe absolute pressure and vehicle speed.

FIG. 5 is a flowchart illustrating the operation flow of the above embodiment.

[Explanation of symbols]

11, 31...Engine, 12...Intake pressure detection means, 13
...Cranking detection means, 14...Rotation speed detection means, 15
...Throttle opening detection means, 16...Reference dynamic pressure detection means,
17...Atmospheric pressure detection means, 18...Atmospheric pressure correction means, 19...
Dynamic pressure P detection means, 20, 21...first and second calculation means, 22...selection means, 23...engine control means, 32...
Intake pipe, 321...Intake pipe duct, 34...Throttle valve, 35...Rotation angle sensor, 36...Intake pipe pressure sensor, 37
...opening sensor, 40 control device, 41...injector, 4
2...Spark plug.

Claims (1)

[Claims] 1. A rotational speed detection means for detecting a rotational speed Ne of an internal combustion engine, and a throttle valve opening degree detection means for detecting an opening degree θth of a throttle valve that controls the amount of intake air to the internal combustion engine, The rotation speed Ne detected by the rotation speed detection means
and the throttle valve opening degree θt detected by the throttle valve opening degree detection means.
In an electronic control device for an internal combustion engine that determines a control amount of the internal combustion engine based on An electronic control device for an internal combustion engine, comprising control amount setting means for determining a control amount for the internal combustion engine in consideration of the dynamic pressure P detected by the dynamic pressure detection means.