JPH01130042A - Controller for internal combustion engine - Google Patents

Abstract

PURPOSE:To aim at reduction in engine control cost by storing data fewer than the whole data area as fundamental data for engine control is advance, and replenishing data in an unstored area in succession on the basis of an actual driving state. CONSTITUTION:When a controller is constituted by a means (b) operating fundamental data from a control value based on an engine driving state detecting means (a), a means (c) operating an engine control value on the basis of this fundamental data or more than at least one among outputs of the driving state detecting means (a) as supplementary data as to an unstored area of a memory means (d), and this means (d) having areas of quantity necessary for engine control, and storing the fundamental data as a control map value in advance while replenishing and storing the supplementary data as the control map value, a means (e) operating the engine control value on the basis of this control map value, and a means (f) operating a control parameter on the basis of this output, data of the unstored area are replenished in succession so that engine control cost is thus reducible.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a control device for an internal combustion engine, and more specifically, to a control device for controlling an internal combustion engine, and more specifically, to reduce the number of man-hours for data input and the number of maps when performing various controls of an engine using a microcomputer. The present invention relates to a control device for an internal combustion engine that aims to reduce energy consumption.

(Prior Art) Recently, with the development of electronics in automobiles, various types of electronic control are being carried out, including control related to engine combustion, and microcomputers have been widely applied to this. has been done. In this case, the microcomputer has an internal map related to combustion control of the engine, and the optimal value of this map is stored in advance through experiments etc., but the more data there is, the more the control accuracy improves. Since the memory area is limited, it is advantageous to have a smaller amount of data, and compromises are made in this respect. Therefore, control using a microcomputer is advantageous in terms of man-hours and number of maps when less data is required, and various measures are needed to meet this desire.

Conventional control devices for internal combustion engines using microcomputers of this kind include various types of control such as ignition timing control and fuel injection control, among which ignition timing control is particularly typical. As a conventional technique for performing such ignition timing control, for example, the first one is Japanese Patent Application Laid-Open No. 53-56429.
There is something described in the publication. This device detects the pressure inside the combustion chamber (hereinafter referred to as cylinder pressure) and determines the torque generated by the engine based on the crank angle θpmax at which the pressure is at its maximum (hereinafter referred to as maximum cylinder pressure timing). The ignition timing is corrected and controlled to match the predetermined crank angle θi to be maximized.

Moreover, as a second type, there is a type described in Japanese Patent Application Laid-Open No. 58-82074. This device detects the cylinder pressure and performs MBT control on the ignition timing so that the θpmax is at a predetermined position that maximizes the torque generated by the engine. Also,
At the same time, knocking is detected by passing a cylinder pressure detection signal through a signal processing circuit, and when the knocking level exceeds a predetermined value, ignition timing is retarded to control knocking with priority over MBT control. Once the knocking is suppressed, the ignition timing is again controlled by MBT so that the torque generated by the engine is maximized.

The microcomputers involved in the control of the two above have internal control maps, such as the basic table for ignition timing as shown in FIG. 22, for example. Then, from this basic table, the engine speed (
The basic ignition timing is determined using engine speed) data and intake air amount data as parameters. This basic table divides the vertical and horizontal axes into equal intervals to create grid points for storing data. In detail, 8 x 8 = 6 in length and width
It is divided into 4 to 16×16=256 grid points, and data is stored at each grid point. In addition, regarding the data that falls between the grids, in order to determine which grid the data corresponds to, the current conditions (engine speed and intake air amount) and the grid data are added in order from the smallest value of the data. Compare with,
Finally, the grid data closest to the current conditions (
Proportional replenishment calculations are performed using two pieces of grid data (on both sides) to calculate the basic ignition timing for the current conditions. Therefore, in such cases, it takes a lot of time to look up the control value.

(Problems to be Solved by the Invention) However, in such a conventional internal combustion engine control device, a basic table is provided inside the microcomputer for ignition timing control, and this basic table contains information in advance. Because the configuration was such that data was stored for all data areas (corresponding to each grid point), it was possible to actually realize the operating state corresponding to each grid point and obtain the operating results. The process of storing optimal control data one by one in the data area, that is, matching the data, takes a lot of man-hours, resulting in an increase in development man-hours, which ultimately leads to an increase in the cost of the engine. There was a point.

Also, in order to store data in all data areas,
Depending on the engine, it is necessary to store data from the beginning even in operating ranges that are actually used very infrequently, leading to an increase in memory capacity. this is,
This leads to an increase in the capacity of the microcomputer, leading to an increase in cost. Furthermore, as mentioned above, data between grids is calculated by interpolation, etc., so the table lookup as a whole takes a lot of time and interferes with other calculation processes necessary for engine control. This had a negative impact on control accuracy.

The above example concerns ignition timing control, but when controlling an engine with a microcomputer that has a basic table, the same applies to other controls such as fuel injection amount control, boost pressure control, etc. There is a problem.

(Purpose of the Invention) Therefore, the present invention stores data less than the entire data area in advance, and then replenishes the data in the unstored area based on the stored data value or the actual operating condition. The purpose is to reduce the cost of engine control by reducing input man-hours, memory capacity, and lookup time.

(Means for Solving the Problems) In order to achieve the above object, the control device for an internal combustion engine according to the present invention provides an operating state detection means a for detecting the operating state of the engine.
and a basic data calculation means for calculating a control value for controlling the engine based on the operating state of the engine as basic data of an area smaller than the total data area of the storage means d. Based on at least one or more of the basic data or the output of the operating state detection means a, control values for controlling the engine are determined for data areas other than the pre-stored portion of the entire data area of the storage means d. It has supplementary data calculation means C which calculates supplementary data for the engine, and a predetermined number of data areas for storing data necessary for controlling the engine, and basic data calculation means C for the areas smaller than the total data area. The calculated data is stored in advance as a control map value corresponding to the operating area at that time, and data areas that are not stored in advance are supplemented with data calculated by the supplementary data calculation means C as control map values. , the storage means d for storing, the control value calculation means e for calculating control values for controlling the engine based on the control map values stored in the storage means, and the control of the engine based on the output of the control value calculation means e. and operating means f for operating parameters related to.

(Function) In the present invention, data less than the entire data area is stored in advance as basic data for engine control, and then an area that is not stored based on a small amount (both based on one or more of the basic data or subsequent operating conditions) is stored in advance as basic data for engine control. data is sequentially replenished.Therefore, data input man-hours, memory capacity, and lookup time are reduced, and costs for engine control are reduced.

(Example) Hereinafter, the present invention will be explained based on the drawings.

2 to 12 show the first control device for an internal combustion engine according to the present invention.
1 is a diagram showing an example, and this example is an example of controlling the ignition timing in particular among the controls of the internal combustion engine.

First, the configuration will be explained. In FIG. 2, reference numeral 1 denotes a sensor group, and the sensor group 1 is composed of a plurality of sensors that detect various parameters related to the operating state of the engine. That is, the sensor group 1 includes a crank angle sensor 2, an air flow meter 3, a throttle valve opening sensor 4, a cylinder discrimination sensor 5,
It is composed of a water temperature sensor 6, an accelerator sensor 7, and a pressure sensor 8.

The crank angle sensor 2 is set at a predetermined position before compression top dead center (TDC) of each cylinder at every explosion interval (crank angle 120° for a 6-cylinder engine, 180° for a 4-cylinder engine), for example, B
A reference position signal S1 that becomes a (H) level pulse at TDC 70° is output, and a unit signal S that becomes an (H) level pulse for every unit angle of the crank angle (for example, 2°).
Outputs 2.

Note that by counting the signal S, the engine rotation speed Ne can be determined, and this processing is performed by the control unit 20, which will be described later. The air flow meter 3 detects the intake air IJQa to the engine, and the throttle valve opening sensor 4 detects the throttle valve opening Cv in accordance with the engine load request. Note that since the throttle valve opening sensor 4 is a sensor for detecting the load of the engine, it is not limited to a sensor that detects the throttle valve opening Cv, but may be a sensor that detects, for example, intake pipe negative pressure. Furthermore, the cylinder discrimination sensor 5 detects a specific cylinder (
For example, the first cylinder) is used to determine a predetermined crank angle position before compression top dead center of a specific cylinder (for example, B of the first cylinder).
At TDC 80°), a cylinder discrimination signal S is output. Therefore, this cylinder discrimination signal S is output once every two revolutions of the crankshaft. The water temperature sensor 6 detects the temperature of the cooling water in the engine, and the accelerator sensor 7 outputs an accelerator signal S7 according to the depression angle of the accelerator pedal. The pressure sensor 8 is composed of, for example, a piezoelectric element built into a cylinder gasket between the cylinder head and the cylinder block, and sends a pressure signal Sll to a charge amplifier (not shown) according to the combustion chamber pressure (in-cylinder pressure) of the engine. The signal is output to the control unit 20 and the knocking detection circuit 9 via the control unit 20 and the knocking detection circuit 9.

As shown in FIG. 3, the knocking detection circuit 9 includes a bandpass filter (BPF) 12 and a waveform shaping circuit 13. The bandpass filter 12 is a pressure signal Sa.
(See Figure 4 (a)), the high frequency component 88, for example, 6 to 15 KI+z, which is particularly abundant when knocking occurs.
' (see Figure 4 (b)) and outputs it to the waveform shaping circuit 13, and the waveform shaping circuit 13 half-wave rectifies the high frequency component 38' and forms an envelope signal from the half-wave rectified signal. (envelope detection) and outputs it to the control unit 20 as a non-king signal S as shown in FIG. 4(c). In addition, in this non-king detection circuit 9, the pressure signal S8 is smoothed to form a background level corresponding to the normal noise level of the engine, and the difference between the formed level and the maximum level of the above-mentioned envelope signal is used as the non-king signal. It may be output as S.

The sensor group 1 and the knocking detection circuit 9 collectively constitute an operating state detection means 10.

Each signal 81 to S9 from the sensor group 1 is input to the control unit 20.
has the functions of basic data calculation means, supplementary data calculation means, storage means, and control value calculation means, and the CPU 21
, ROM22, RAM23, NVM (non-volatile memory)
24, and an input control circuit 25 having built-in input/output interfaces, registers, counters, A/D converters, high frequency cut filters, and the like. The CPU 21 takes in necessary external data through the input/output control circuit 25 according to the program written in the ROM 22, and performs knock avoidance control, MBT control, and control data while exchanging data with the RAM 23. The processing value necessary for setting replenishment is arithmetic processed, and the processed data is output to the input/output control circuit 25 as necessary. Signals from the sensor group 1 and the knocking detection circuit 9 are input to the input/output control circuit 25, and the ignition signals S,
. is output.

The ROM 22 stores the calculation program for the CPU 21, and also stores a predetermined number of data smaller than the total data area in the basic ignition timing map.
23 performs temporary storage of data used in calculations and supplementary data and storage for data areas other than the pre-stored portion of the total data area, and NVM 24 retains the stored contents even after the engine is stopped.

Ignition signal S. is input to the ignition unit (operating means) 26, and the distributor 30 is input to the ignition plug 27.
a to 27f, an ignition coil 28, a power source 29, a distributor 30, and a power transistor Q1. The input/output control circuit 25 generates a high voltage (I) on the secondary side of the ignition coil 28 by turning the power transistor Q (0N10FF ml 'a) on the basis of the ignition signal S1°, and distributes this high voltage VH by the distributor 30. is supplied to the spark plugs 27a to 27f to ignite the air-fuel mixture. Note that this ignition timing control (ON10FF control '4n of the power transistor Q) is performed by setting a value (advance value) corresponding to the determined ignition timing in an advance value (ADV) register (not shown) provided inside the input/output control circuit 25. The value of these registers is compared with the count value of the position signal S2, and when they match, the power transistor Q is turned on or off.

Next, the operation will be explained, but first the basic principle of this embodiment will be explained. The basic principle of this embodiment is shown in the program shown in FIG. The prerequisites for running this program are:
It is as follows.

First, a table of basic ignition timing for ignition timing control is prepared in advance in a predetermined area of the ROM 22, and optimal control values obtained through experiments and the like are stored in each area of this table. This is a process equivalent to the data matching described above, and is performed at a predetermined stage before shipment from the factory. In this case, the predetermined area (memory area) of the ROM 22 does not correspond to the entire operating range as in the past, but only to the area corresponding to the operating range corresponding to the idle condition and other minimum necessary conditions, for example. be. As this basic table, for example, as shown in Fig. 6(b), a two-dimensional table is used to divide the intake air ff1Qa (q+ ~ q3) and the engine speed N (n, ~ n3) into three stages. and add data AII' to this
~A33' is stored.

Therefore, the memory area to be stored in the ROM 22 can be much smaller than in the past, which leads to a reduction in matching man-hours and memory capacity.

On the other hand, for areas where basic data is not stored, the memory areas of the RAM 23 and NVM 24 are utilized as learning tables, and subsequent supplementary data is sequentially stored therein. As a study table, for example, Figure 6 (a
), we prepared a two-dimensional table that divided both the intake air amount (Q, ~Q8) and the engine speed N (N, ~N,) into 8 stages, and calculated 8 x 8 = 64 tables. Ignition timing data (Az to A38) is stored at each grid point. In this case, since some driving areas may never be used depending on the vehicle, the actual memory area used can be small, unlike the conventional method of preparing basic data for all data areas from the beginning. . In addition, the supplementary data is not calculated by interpolation of basic data, but is immediately calculated in a normal calculation format based on the actual operating conditions at that time and the average value of data in adjacent mnemonic areas. Differently, the calculation time is short. The supplementary data thus obtained is stored in the corresponding data area.

This data processing part is performed by the program shown in FIG. Moving on to Fig. 5, the data area of the learning table corresponding to the current operating state is determined using the intake air ff1Qa and the engine speed N as parameters at P, and P2
Then, it is determined whether the current data area is the first area specification for that area. When specifying an area for the first time, data has not yet been stored in the area, so in P3, the optimum value for ignition timing control is calculated based on the average value of data in adjacent mnemonic areas and the current combustion state. This is stored in the corresponding area as supplementary data.

As a result, map areas other than the basic data and previously replenished data are newly replenished with data, and this replenished data is immediately looked up when the same area is specified next time. On the other hand, when the area is not specified for the first time in P3 (second time or later), the optimum value of the ignition timing side tall is calculated based on the current combustion state in P4,
Updates mnemonic data with new calculated values. As a result, the latest data is always recorded in the corresponding area tα following changes in the engine and control device over time, which is one of the great advantages of so-called learning control.

Based on the above basic principle, in this embodiment, the ignition timing is controlled by the programs shown in FIG. 7 and thereafter.

First, the combustion peak position θ required for MBT control
A subroutine program for calculating pmax (referring to the crank angle when the combustion chamber pressure reaches the maximum; the same applies hereinafter) will be explained with reference to FIG. 7. The program shown in FIG. 7 is based on the position signal Sl from the crank angle sensor 2.
It is executed once every 2°C and A in synchronization with .

First, the A of the signal S8° (see Fig. 8 (b)) obtained by cutting the high frequency component from the pressure signal Ss (indicating a signal equivalent to one cylinder) changing as shown in Fig. 8 (a) at Pl+. /D conversion is determined whether it is the timing to start or not, and if it is not the start timing, immediately returns to the main routine shown in FIG. 9, and when it is the start timing, the P
, proceed to □.

Specifically, the Pl+ discrimination process is performed as follows.

That is, the input/output control circuit 25 counts the position signal Sl (2° signal) from the crank angle sensor 2 (see FIG. 8 (c)) using an internal counter.
This counter is the cylinder discrimination signal S from the cylinder discrimination sensor 5.
The count value is reset every time , is input. Then, the count value of this counter is read every time the pH is executed, and this read value corresponds to the crank angle range of the combustion stroke of each cylinder.
20-180, 180-240.240-300.30
x predetermined for every 0 to 360 for θpmax detection,
x+5Q, x+120, X+180. X
+240. The first flag is set every time it matches X+300. The first flag is reset at the time when θpmax, which will be described later, is calculated, and the process is allowed to proceed to PI2 only while the first flag is set. At pH x+6on (n=1,2
．． In order to detect the crank angle based on 3...), set the crank angle counter (soft counter) to [+
1) Count the amps (corresponding to 2° CA). Next, the A/D converter of the input/output control circuit 25 is activated by the PI3 to A/D convert the pressure signal S8 at that time, and this A/D converted value is read after, for example, several tens of microseconds.

In PI4, the difference value ΔP between the A/D converted value of the pressure signal SIl between the previous time and the current time is calculated according to the following equation (2).

ΔP=AD 1-ADφ ・・・・・・■ However, AD
I: Current A/D conversion value ADφ: Previous A/D conversion value (At first, the difference value ΔP is then compared with the reference value ΔP0 using pus.

The reference value ΔP0 is a value for determining that the signal level of the pressure signal S8 has reached the maximum, and is set to a predetermined value in advance. When ΔP≧ΔP0, it is determined that the signal level of the pressure signal S8 has not reached the maximum, and the current A/D conversion value ADI is returned as the rice transplant ADφ at PI6. On the other hand, ΔP
<When ΔP0, it is determined that the signal level of the pressure signal S8 has reached the maximum, and PI? From the count value α of the crank angle counter at that time and the above-mentioned X, the combustion peak position θpm is determined.
Calculate ax according to the following formula 〇.

θpmax=2 (z+x) 80 −・”■
θpmax is expressed as a crank angle with respect to top dead center. Then, when the calculation of θpmax is completed, the first
flag and also reset the count value of the crank angle counter.

Next, PI8 clears ADφ to zero for the next A/D conversion and returns.

By sequentially performing the above processing, the combustion peak position θp
max is required.

Next, ignition timing control will be explained with reference to the program shown in FIG. This program is executed once every time θpmax is calculated.

First, at P2°, the basic ignition timing ADVφ is look-amplified from a basic table as shown in FIG. 6(b) using the engine speed N and intake air 1tQa as parameters. This table map is given as a function of engine speed N and engine load (in addition to using intake air amount Qa as data, data based on negative pressure sensor output such as throttle valve opening and intake pipe internal pressure may also be used). In the low load range, it is set to approximately MBT conditions, and in the high load range, it is set according to the knocking level. However, this table map is created by matching, for example, the median value of these variations, without taking into account individual engine variations, changes over time, environmental changes (humidity changes, fuel octane changes, etc.), and the MBT described later. Control absorbs these fluctuation factors and maintains the accuracy of the data.

Next, the learning value ADV 1 (signed data with + and -) of the ignition timing correction amount learned and stored in the learning table (shown in FIG. 6 (a)) of the NVM 24 by executing this routine in PZ+ is transferred to the above-mentioned data. Similarly, a table map with N and Qa as parameters is looked up. 3rd in pzt
In the non-king detection circuit shown in the figure, the knocking signal S from circuit 9 is A/D converted and taken in as knock level data KV, and in P23 this KV is set to a predetermined slice level KVφ.
Compare with.

KVφ is set, for example, to a value corresponding to a knock level that is extremely slight and poses no problem in practice. When KV<KVφ, it is determined that no knock has occurred, and MBT control of the ignition timing is performed in conjunction with the above learned value ADVI so that the combustion peak position θpmax is at a predetermined position where the generated torque is maximized at PZ4. , pzs to output the ignition signal SIO.

On the other hand, when KV≧KVφ, it is determined that knocking is occurring, and the ignition timing is controlled to knock at PZ& to suppress knocking, and the process proceeds to PZ.

Next, regarding the MBT control performed in step P24,
This will be explained with reference to the program shown in FIG. In P3□, it is determined whether the engine is in a transient operating state. When Pffl determines that the engine is accelerating, the process proceeds to P4°, and when pig determines that the engine is decelerating, the process proceeds to P4S.

On the other hand, if it is determined in P3□ that the engine is not in a transient operating state but in steady operation, the process advances to Pff3. Specifically, these determinations are made by converting the accelerator signal S7 from the accelerator sensor 7 into an A/D converter of the input/output control circuit 25.
This is done by comparing whether the amount of change per unit time of the D-converted data is larger than a predetermined value.

Although the above determination can be made using other determination factors such as the intake air amount signal S or the load signal S4, it is preferable to use the accelerator signal S7 because it has the fastest response to changes in the accelerator depression amount. is desirable.

In Pff3, it is determined whether the crank angle θpmax at the time of maximum cylinder pressure obtained in PI7 of FIG. 7 is within a predetermined target crank angle range θM, ~θMz (θM, <θMZ), When ≦θpmax≦θM2, Pd
If θpmax<6M1, the process proceeds to P34, and if θpmax>0M2, the process proceeds to P3b.

The purpose of setting this target crank angle range is to increase the stability of MBT control, and the range is set so that the torque is reduced by about 0.5% above and below θM, based on the crank angle θM at the time of maximum torque generation. The angle side is 6M7 and the advance side is 0M2. However, since the engine torque characteristics change depending on the engine operating condition, θM+
, 0M2 may be set to barrier pull depending on the operating condition. In P34, θpmax <
It is determined whether the state 6M1 continues for more than a predetermined number of ignitions, and if it continues for more than 0 times, it is determined that the crank angle θρmax is advanced, and P3S is activated. Performs advance angle correction control. The processing of P34 is performed by PI? in Figure 6. Since the crank angle θpmax determined by is often unstable due to changes in the operating state of the engine, this is done in order to reduce erroneous judgments due to this instability. In P35, the previous feedback amount FB(θp
Advance angle correction processing is performed using the value obtained by adding 1° CA to the value as the correction amount of the ignition timing based on max (the initial value is zero) as the current feedback amount FB.

On the other hand, when PI3 judges that it is not consecutive 0 times, jumps pis and presses P. Proceed to.

In P36, it is determined whether the state judged as θpmax > 0M2 in P13 continues continuously for a predetermined number of m ignitions or more, and if it continues continuously for m recovery, the crank angle θpmax is retarded. It is determined that there is a retard angle correction control in P4□. On the other hand, when under m recovery, P3? Jump to page 311. In addition, rnJ of P34 and P
Regarding the relationship with rmJ of 3h, the torque decrease is greater when θpmax <6M1 than when θpmax >0M2, so n<m. In Py7, a retardation correction process is performed in which the value obtained by subtracting I''CA from the previous feed bank amount FB is set as the current feedback amount FB.

At P4g, the final ignition timing ADV is calculated by the following equation (2) based on the basic ignition timing ADVφ obtained from P2° and PZI in FIG. 9, the learned value ADV 1, and the feedback amount FB obtained from P3S and P37.

ADV=ADVφ+ADV l +FB...
・■Also, when the engine is accelerating (during transient operation) at P31, the ignition timing correction control based on the crank angle θpmax is interrupted and the process proceeds to P4°. In other words, during acceleration operation, θpmax becomes extremely unstable, the air-fuel ratio becomes lean due to the injected fuel adhering to the wall, and the ignition timing is set to be more advanced under low load conditions than under high load conditions. For example, the retardation amount table for knock avoidance during acceleration stored in the ROM 22 in advance may be changed to the time change rate of engine speed data and engine load data (time differential value of engine load data). ) to find the retard amount δ2 corresponding to the current acceleration driving state, and then calculate the retard amount δ2 that corresponds to the current acceleration driving state.
After processing to set the value obtained by adding a negative sign to 2 as the feedback jlFB--δ2, the process immediately proceeds to P4[1. Note that FB in this case does not, of course, mean a feedback control amount related to MBT control.

Further, when it is determined in Pl3 that θM, ≦θpmax≦θM2, the engine is not in a transient state and the crank angle θpmax is controlled within the target crank angle range, so the feedback IFB learning and storage process is performed. However, immediately after transient operation, that is, immediately after acceleration/deceleration, for several seconds (T1 seconds), there are effects such as delayed response of the air flow meter 3 and torsional vibration of the engine crankshaft. Check whether T1 seconds have elapsed (it is preferable to vary this depending on the operating state of the engine or the cooling water temperature), and if T1 seconds have not elapsed, the learning/memory process is postponed and the process proceeds to Pffll. In P311, if proceeding from P4o, use FB=-62, P4
If you have proceeded from 1, the previous feedback IFB
Each final ignition timing ADV is calculated using the formula 0. It is assumed that the value of FB is reset from - δ2 to zero, for example, between P3Z and P3ff immediately after transition from accelerated operation to steady operation. In P4□, it is determined whether the feedback iFB is zero or not, and FB=0
In that case, there is no need to rewrite ADI in Pl3, so Pa
Proceed to s, and if FB≠0, proceed to Pl3. P4ff
In this case, the engine has been sufficiently warmed up, the engine is not in a transient operating state, the crank angle θpmax is within the target crank angle range, T seconds have elapsed since the transient operating state, and F
Since B≠0, feedback iFB is set to learning value AD
As V1, the learning value ADV 1 is updated and stored in the grid point of the learning table for ADVl in the NVM 24. In addition,
If the actual engine speed data and engine load data do not match the two data that define the grid points of the learning table, take these discrepancies into consideration and apply weighting (interpolation) to the FB, and then The updated value is updated and stored at the approximate grid point (this process is reversed when table look is performed at P2° in FIG. 9).

Also, the feedback iF updated and stored in this Pl3
B is always subjected to the above-mentioned P3S or P37 processing, so this feedback IFB is determined by the crank angle θ.
It can be regarded as the amount of correction of the ignition timing based on pmax.

At P44, the feedback amount FB used for rewriting at P13 is cleared to zero. At P4'5, ADVφ obtained at P2゜ in Fig. 9 and the new A rewritten by Pl3.
Calculate the final ignition timing ADV from DV 1 using the following formula (2).

ADV=ADVφ+ADV 1 ・・・・・・■ Also, when it is determined that the engine is decelerating at P3□ or when FB=O is determined at P4□, each directly
We will proceed to as, but ADV 1 to be used in these cases
is ADV1 determined by PH1 in FIG.

Returning to FIG. 9 again, in Pzb, various processes related to knocking avoidance control as shown in FIG. 11 are performed.

First, P. Now, the current feedback amount KFB is the value obtained by subtracting the predetermined amount δ3 that should be retarded for each ignition from the previous feedback amount KFB (value as a retard correction amount to avoid knocking; the initial value is zero). Perform corner correction processing and proceed to PSI.

In PSI, the same process as in Pal shown in FIG. 10 is performed, and if the engine is accelerating, the process proceeds to P and 3, and if the engine is not accelerating (transient operation), the process proceeds to PS2. At P, 2, after acceleration T, (T, ≧T2: This T2 is also preferably variable depending on the engine operating state and cooling water temperature)
Check whether or not seconds have elapsed. If 12 seconds have not elapsed, proceed to psi, and if 12 seconds have elapsed, proceed to PS4. For PS3, P2° in Fig. 8, ADVφ determined by Pal
, ADVl and P,. The amount of feedback KF obtained by
Based on B, the final ignition timing ADV for avoiding non-king is calculated using the following equation (2).

ADV=ADVφ+ADV 1 +KFB・・・・・・
■In PS4, at least T2 seconds have passed after acceleration, and the engine is in a stable state without a transient operation state, so the feed hack 1KFB (ignition timing retardation correction amount by knock avoidance control) at this time is set to the learned value ADV 1 After updating and storing in the lattice points of the learning table of ADV 1 in the NVM 24 determined by the engine speed data and engine load data at this time, the process proceeds to Pus. P5
In step 5, the final ignition timing ADV at the time of rewriting the table is calculated by the following equation (2) using ADVφ obtained at P2° in FIG. 9 and the new ADV 1 rewritten in PS4.

ADV=ADVφ+ADV 1 ・・・・・・■ In this knocking avoidance control routine, it is assumed that, for example, the process of P3.3 is performed when the engine is decelerating or during steady operation after deceleration. Sometimes AD
(You may also rewrite V1).

Returning to Figure 9, is the MBT system for pza? 1[1 or P2
PZ executed after knocking avoidance control in step 6 is performed.
In S, P 3B-, P 45, psi and Pl, (
10 or 11) is subtracted from 70° CA (70-8D■), and outputs the value (70-8D■) to the register of the input/output control circuit 25 shown in FIG. Thereafter, the processing of this processing program is temporarily terminated.

Then, each time the above processing is performed (70-AD
When the value V) is written into the register of the input/output control circuit 25, an ignition signal S_IQ is formed and output to the power transistor Q1 of the ignition unit 26 in the following manner.

That is, in the input/output control circuit 25, for example, as shown in FIG.
As shown in (a) to (c), when the reference position signal S1 is input from the crank angle sensor 2, the counter value is reset to zero, and after that, each time the unit angle signal S2 is manually input, the counter value is reset at the rise and fall of the unit angle signal S2. The value is counted up by 1 every 1°CA. On the other hand, 7O-ADV is written in the register at a predetermined timing as described above, and the value of this register is compared with the value of the counter described above, and when the two match, the ignition signal S1° is ignited. It outputs to the power transistor Q of the unit 26. Then, the above ignition signal S1° is transmitted to the power transistor Q1
When the power transistor Q1 is output from ON to OFF, the high voltage generated on the secondary side of the ignition coil 28 is passed through the distributor 30 to the spark plug (one of 27a to 27f) in the ignition order. ignition is performed.

By operating the control unit 20 as described above, the past history of the ignition timing correction amount by MBT control and the ignition timing retardation correction amount by non-king avoidance control is always utilized in calculating the current ignition timing. In addition, MBT control is interrupted during transient operation, which not only prevents the ignition timing correction amount from changing significantly and causing torque fluctuations when engine operating conditions change, but also reduces uncertainty during transient operation. As ignition timing control is no longer performed, engine drivability improves, and knocking can be prevented to some extent through learning, which expands the range in which MBT control is effective, thereby improving engine output. can be achieved.

Regarding the first embodiment described above, the effects with respect to the prior art will be considered.

(1) The number of grids in the basic table is small, and the man-hours required to store basic data in advance are extremely reduced. Therefore, the memory area of the ROM 22 may be much smaller, and a storage element with a small memory capacity may be used.

(II) RAM2 for supplementary data other than the basic table
Although the learning tables of 3 and NVM24 are utilized, there may be driving areas that are not used depending on the vehicle type, so the actual memory area used can be small.

(III) Unlike the conventional simple interpolation method, supplementary data is calculated in a normal calculation format, so calculation time is short and there is no interference with other control processing, improving control accuracy. .

(IV) As described above, the number of development steps, memory capacity, and microcomputer capacity can be reduced, and the cost of the engine can be reduced.

In the first embodiment, the pressure sensor 10 incorporated in the cylinder gasket was explained as an example, but the invention is not limited to this. For example, a pressure sensor in which a piezoelectric element formed in the shape of a washer is incorporated as a washer in each spark plug may be used. You can also use

Further, in the first embodiment, an ignition timing control device for an internal combustion engine that performs both MBT control and knock avoidance control was explained as an example, but in the case of a device that performs only MBT control, the non-king detection circuit shown in FIG. In addition to removing 9, PI2, PI3, and P in the flowchart of FIG.
16 (P in Figure 11.

. . . 5)), and of course the above-mentioned effects corresponding to the configuration can also be achieved in this case as well.

13 to 15 are diagrams showing a second embodiment of the present invention,
This second embodiment differs from the first embodiment in the basic table. In other words, the idea of the second embodiment is as shown in FIG. 13(a).
As shown in (b), the intake air amount Qa (q+~q
4) and the engine speed N (n+~nm) are used alone as a one-dimensional table, and data A, ~A4, A
, '~A4'. However, in the second embodiment, the basic data is not divided into four pieces, but is actually divided into five pieces as shown in FIG.

In Fig. 14, the intake air amount Qa corresponding to the engine load
and engine speed N as parameters, A8 is the basic ignition timing near idling conditions, A2 is the basic ignition timing corresponding to city driving conditions, A1 is the basic ignition timing corresponding to low rotation and high load, and basic is equivalent to high rotation and low load. Set the ignition timing to A4
, the basic ignition timing corresponding to high rotation and high load is stored in advance as A.

FIG. 15 is a flowchart showing a program for ignition timing control.
Steps that perform the same processing as in the program shown in the figure are given the same numbers and their explanations are omitted, and steps that are different are given step numbers circled and their contents will be explained. p6+
The step ~P6S is to determine which region in Fig. 14 the current engine speed N and intake air 4JQaO value correspond to, and based on the determination result, step P66~
At step P7°, the basic ignition timing ADVφ corresponding to each operating region is set.

P61-P6. The following conditions are determined in step .

P61: P6 to compare engine speed N with predetermined value N
g'Compare engine speed N with predetermined value N2 (however,
Nl<N2) P63: Compare intake air amount Qa with predetermined value Q, Pb0
．． Pbs: Compare the intake air amount Qa with a predetermined value Q2 (however, Ql < Qz) Based on the above determination, P66 to P under the following conditions for each operating region. Proceed to.

When proceeding to Pb0, N<Nl, and when Qa<QI, ADVφ=A +.

p6? When proceeding to N, ≦N<N 2 , and Q + ≦Qa<Ql, AD■φ=A z .

N when proceeding to PbS, A when ≦N<Nz, Ql ≦Qa, Qz≦Qa
Let DV=A3.

N when proceeding to P69, ADV when ≦N, N, ≦N, Q, ≦Qa<Ql
=A.

P. When proceeding to N, ≦N, NZ≦N, Q, ≦Qa, A when Q2≦Qa
Let DV=AS.

The above PHI~P. After passing through the steps, the step processing after pz+ is executed in the same way as in the first embodiment.

As a result of the above, the same effects as in the first embodiment can be obtained, but the basic ignition timing ADvφ is 5.
Therefore, the memory capacity and the number of development steps can be reduced more than in the first embodiment.

Figures 16 and 17 are diagrams showing a third embodiment of the present invention,
This third embodiment is based on step P in the second embodiment described above.
61, a predetermined value N1 for determining the engine rotation speed N is provided with a predetermined hysteresis.

In the program shown in Figure 16, P? I~P? Step 5 is for making the value of N1 set in FIG. 14 have a range as shown in FIG. This is because the determination becomes ambiguous. Therefore, the engine speed N is N I I ~
Set in the range N, 2 (N + r < NI□)
However, the engine speed N is N1. When flag FN,
=0, and when NI2, the flag FN is set to =1 to perform area discrimination.

Return to Figure 15 again and select P? When N<N11 in I, P,
2, FN=0 and proceed to Pb0. On the other hand, Pfu, N
When ≧N11, proceed to P73; when N<N+z, proceed to P,
4 determines whether FN is 1 or 0, and if FN = 0, Pb
Go to 0. Also, when N≧NIz in Puff, Pl,
Then, set FN=1 and proceed to Pb0. therefore,
When FN=1 in pta, proceed to Pb0. Note that the other steps are similar to those in the second embodiment and are given the same numbers.

In this way, in the third embodiment, a predetermined hysteresis is provided for the predetermined value N+ for determining the engine speed, so that the operating range during sudden acceleration can be reliably determined, and in addition to the effects of the first embodiment. It is characterized by improved stability of ignition timing control.

FIG. 18 is a diagram showing a fourth embodiment of the present invention. In this embodiment, the basic ignition MAD ■φ range is determined based on the output information from the throttle valve opening sensor 4. FIG. FIG. 18 is a flowchart showing a program for ignition timing control. In this figure, it is first determined whether or not the idle region is reached using pH+, and when it is in the idle region, the basic ignition timing is set to ADVφ-A using P8Z. , if it is not the idle area, set ADVφ=AZ in P83 and proceed to P21.

The steps after PZ+ are the same as in the first embodiment and are given the same numbers.

Therefore, in the third embodiment, the same effects as in the first embodiment can be obtained, and in particular, the basic ignition timing range discrimination is further simplified, so that the processing time of the entire ignition timing control program is longer than the third embodiment. It has the advantage that it is shorter than the embodiment, improves control responsiveness, and is advantageous in terms of memory capacity, etc.

19 to 21 are diagrams showing a fifth embodiment of the present invention,
In this fifth embodiment, both the basic table and the learning table utilize memory areas in the RAM 23 and NVM 24, and part of the basic data is stored in the RAM 23 and NVM in an initialization routine when power is turned on to the control unit 20.
24.

First, as shown in FIG. 19, the RAM 23 and NVM 24
A map is provided in which the horizontal axis is the engine speed N and the vertical axis is the intake air amount Qa, and is composed of 8 x 8 = 64 equally spaced grid points. Then, for example, near the idol,
The data on the ignition timing at each representative point in the city direct mode area and the full throttle area was examined in detail during the development stage, and A 11, Azz, Ass, A z were added to the corresponding portions of the grid points.
B, A 33, A 5 z, A4. They are given in advance as constants such as B and A81+. Note that since there is no data in the area other than the basic data Aij (which becomes the learning data) at the beginning, the data around this area is represented by the basic data Aij.

FIG. 20 is a flowchart showing an initialization routine for initially storing the above data in a predetermined area of the RAM 23 or NVM 24. First, the basic data Aij given as described above is initially stored in the RAM 23 or NVM.
24 and is called by the initial program. Therefore, at the same time as power is turned on to the control unit 20 at PH1, the basic data Aij is stored in the corresponding predetermined area. This store area is the first
It is shown as in Figure 9. Then P? Learning data ai with g
j is stored in a predetermined area, but initially in RAM
Since there is no data in 23 or NVM 24, the value of aij is obtained by interpolation from a plurality of adjacent Aij, and after the initial data is determined, the aijO value is sequentially updated by so-called learning control. Note that the AijO value may also be updated sequentially by learning control, and in this way, the entire map value is updated as more accurate data and the control accuracy is increased. Note that the above example uses data aij
This is an example of performing interpolation calculations from basic data Aij, but in order to speed up the calculation process, aj
The corresponding area of j may be represented by one of the values of Aij, and the value may be updated by learning calculations from the second time onwards.

a 21 = 221 = A I 1 %a Ll
= 332= 313= a Z3= AlBSa a
t = a az= a 43° a14=a24°
a34=a44=A28・aSI=261=271=281=26Z=a? 2=a
l12=a S3= a 63- a 7ff= a
83-A52%a,, = a, 6= az6=
a35=a45”3.,=a,62Az5・aS4=a64=a 74=al14=26S=a7S
=allS=a 5b=a bb=a 76=a
sb=ASS~a 17=22? = 33'
l= 2 18= 23B= A2B%a 4? =
a sr= a 6? = a a8= a
be=AS11%a'? ? = a8? = a 711
= A88% Fig. 21 is a flowchart showing the ignition timing control program, and ADVI is looked up in the table at P91.
Aij and aij stored in .

Therefore, in this fifth embodiment, the RAM 23 and NVM 24 are used instead of the ROM 22 as storage areas for basic ignition timing data in ignition timing control, and the amount of basic data given in the initialization routine is extremely small, only a few pieces. Therefore, the number of basic data AijO calculated and given in advance is small, and it is possible to obtain all the same effects as in the first embodiment, such as the effect that the man-hours for engine mantisogging and the development cost can be reduced.

Further, the difference from the first embodiment is that even the basic data can be sequentially updated by later learning control, and in this point, more accurate engine ignition timing control is possible.

Note that, although the first to fifth embodiments described above are examples in which the present invention is applied to ignition timing control of an internal combustion engine, the application of the present invention is not limited to this. In short, it can be applied to anything that controls an internal combustion engine using a microcomputer, for example, in addition to ignition timing control, fuel injection control,
The present invention can be applied to any system in which a microcomputer has a map in GR control, boost pressure control, etc., and controls are performed based on the map values.

(Effects) According to the present invention, data smaller than the entire data area is stored in advance as basic data for engine control, and then areas that are not stored are based on at least one of the basic data or the subsequent operating state. Since the data is sequentially replenished, the number of man-hours for data input, memory capacity, and lookup time can be significantly reduced, and the cost for engine control can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a basic conceptual diagram of the present invention, Figs. 2 to 12 are diagrams showing a first embodiment of the invention, Fig. 2 is a block diagram of the main part including the control unit, and Fig. 3 is a diagram of the main part including the control unit. A detailed block configuration diagram of the knocking detection circuit, FIG. 4 is a diagram showing the operation of the knocking detection circuit of FIG. 3, FIG. 5 is a flowchart showing the program of its basic principle, and FIG. 6 is a diagram showing its learning table. , FIG. 7 is a flowchart showing the program for detecting °θpmax, FIG. 8 is a waveform diagram showing the signal processing waveform, FIG. 9 is a flowchart showing the ignition timing control program, and FIG. Flowchart showing MBT control program, No. 11
9 is a flowchart showing the knock avoidance control program, FIG. 12 is a timing chart showing the action of the counter in the input/output control circuit, and FIGS. 13 to 15 are diagrams showing the second embodiment of the present invention. Fig. 13 is a basic table for determining the basic ignition timing, Fig. 14 is a diagram showing the operating range of the engine, Fig. 15 is a flowchart showing the ignition timing control program, and Figs. 16 and 17 are the main tables. FIG. 16 is a diagram showing a third embodiment of the invention, and FIG. 16 is a flowchart showing the ignition timing control program;
Figure 7 is a diagram showing the effect of the signal in the operating range of the engine.
FIG. 18 is a flowchart showing the ignition timing control program of the fourth embodiment of the present invention, and FIGS. 19 to 21 are diagrams showing the fifth embodiment of the present invention, and FIG. 19 shows the basic ignition timing. 20 is a flowchart showing the initial program, FIG. 21 is a flowchart showing the ignition timing control program,
FIG. 22 is a diagram showing a basic table for determining the basic ignition timing showing conventional ignition timing control. 10... Operating state detection means, 20... Control unit (M main day')
calculation means, supplementary data calculation means, storage means, control value calculation means), 25...Ignition unit (operation means).

Claims (1)

[Scope of Claims] a) Operating state detection means for detecting the operating state of the engine; b) Based on the operating state of the engine, control values for controlling the engine are stored in a basic area smaller than the entire data area of the storage means. c) at least one of the basic data calculated by the basic data calculation means or the output of the operating state detection means;
d) supplementary data calculating means for calculating a control value for controlling the engine as supplementary data for a data area other than a pre-stored portion of all data areas of the storage means, based on one or more of the following: It has a predetermined number of data areas for storing data necessary for control, and the data calculated by the basic data calculation means for areas smaller than the total data area are used as control map values corresponding to the operating area at that time. and (e) the control stored in the storage means. control value calculation means for calculating control values for controlling the engine based on map values; and f) operation means for manipulating parameters related to engine control based on the output of the control value calculation means. Characteristic internal combustion engine control device.