JPH01219352A - Ignition timing controller for engine - Google Patents

Abstract

PURPOSE:To make proper ignition timing settable to any vibration in load by performing no compensation for the ignition timing as long as the specified time since a load change has been detected. CONSTITUTION:A controller 30 compensates ignition timing from a deviation between mean speed and momentary speed of an engine 1 at idling state when an idle switch 12A is turned to ON. Here a microcomputer 32 erects a flag in response to a signal read from an air-conditioning switch 19 via a driver 40, and judges of whether load of the engine 1 is changed or not by comparison between both states of the last and this time flags. If the load changed, lag time is set to a timer 38, and the ignition timing is made so as not to be compensated even if it is at the time of the idling state. With this constitution, since a speed upping rate is not checked by timing delay compensation, the engine is reachable to the required speed so quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine ignition timing control device that controls the ignition timing of an engine based on the load and rotational speed of the engine.

[Conventional technology]

A conventional device of this type includes a rotation signal generating means for generating a rotation signal corresponding to the engine rotation speed, a rotation speed calculation means for inputting this rotation signal and calculating an instantaneous rotation speed and an average rotation speed, and a rotation speed calculation means for inputting this rotation signal and calculating an instantaneous rotation speed and an average rotation speed of the engine. load detection means for detecting a load; ignition timing control means for controlling the ignition timing of the engine based on the load and rotational speed of the engine; and correction for correcting the ignition timing based on the deviation between the average rotational speed and the instantaneous rotational speed. For example, the rotational speed during idling is stabilized by correcting the ignition timing by the correcting means.

[Problem to be solved by the invention]

Since the conventional engine ignition timing control device is configured as described above, when controlling the engine speed in the upward direction by, for example, increasing the idle speed, the average speed changes in response to an increase in the instantaneous speed. If the ignition timing is corrected by the correction means due to the delay in tracking, the ignition timing will be controlled in a retarded direction, and the rate of increase in rotational speed will be controlled in a direction that reduces the ignition timing, so that an appropriate ignition timing can be adjusted in response to load fluctuations. There were problems such as being unable to set the rotation speed quickly and controlling the rotation speed to the required speed.

This invention was made in order to solve the above-mentioned problems, and provides an engine ignition timing that can set an appropriate ignition timing by not correcting the ignition timing for a predetermined period of time after the load changes. The purpose is to obtain a control device.

[Means to solve the problem]

An engine ignition timing control device according to the present invention is a device equipped with a correction means for correcting ignition timing based on a deviation between an average rotation speed and an instantaneous rotation speed, and a load change detection means for detecting a change in engine load. The correcting means does not correct the ignition timing for a predetermined period of time after detecting the load change.

(Function) The engine ignition timing control device of the present invention suppresses the rotational increase rate when the load changes due to cooler idle up, etc., so that the correction means does not retard the ignition timing for a predetermined period of time from that time. The required rotation speed can be reached quickly without any problems.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure shows the configuration of an engine ignition timing control device according to an embodiment of the present invention, where 1 is a well-known engine installed in, for example, an automobile, and 1o is a Karman vortex air flow sensor (hereinafter referred to as AFS), which will be described later. 11 is a surge tank, 12 is a throttle valve, 12A is a throttle valve 12 at idle.
13 is an AFS that detects the intake air amount, 14 is an injector, 15 is an intake pipe, 1
6 is an exhaust pipe. The AFS 13 outputs a pulse with a frequency corresponding to the amount of air taken into the engine 1, and the crank angle sensor 17 outputs a pulse as a crank angle signal according to the rotation of the engine 1 (for example, a crank angle signal from one pulse rise to the next rise). For example, a 1° signal is output for every l° of crank angle. 18 is a water temperature sensor that detects the cooling water temperature of the engine 1, and 19 is an air conditioning switch that is connected to an air conditioner such as a cooler of an automobile, and connects the air conditioner to the engine 1 and operates it when turned on. 2
0 is an AN detection means that counts the number of output pulses of the AFS 13 that fall between a predetermined crank angle of the engine 1 based on the output of the AFS 13 and the output of the crank angle sensor 17. 21
is a control means, which includes a crank angle sensor 1 that detects the output of the idle switch 12A and a predetermined crank angle of the engine 1;
7, the output of the water temperature sensor 18, the output of the air conditioning switch 19, and the output of the AN detection means 20, and controls the driving time of the injector 14 in accordance with the intake air amount in a predetermined crank angle section of the engine 1. The energization of the ignition coil 22 is controlled according to the intake air amount and the rotation speed, and the ignition timing is corrected based on the deviation between the average rotation speed and the instantaneous rotation speed during the idle state, thereby the amount of fuel supplied to the engine 1. and control ignition timing. Further, the control means 21 controls the calculated engine 1 even if the idle switch 12A is in the idle state when the idle switch 12A is turned on within a predetermined period of time after the air conditioning switch 19 is turned on and the load on the engine 1 changes.
The ignition timing is not corrected based on the deviation between the average rotational speed and the instantaneous rotational speed. Further, the ignition coil 22 supplies its output voltage to the ignition plug 24 via the power distributor 23 to ignite the spark plug 24 .

FIG. 2 shows a more specific configuration of this embodiment, where 30 indicates an idle switch 12A, an AFS 13. Water temperature sensor 18
．． The control device receives the outputs of the air conditioning switch 19 and the crank angle sensor 17, and controls the four injectors 14 and ignition coils 22 provided for each cylinder of the engine 1. A ROM 3 which corresponds to the means 2o and the control means 21, stores the flowcharts of CPυ31A, FIGS. 3, 5, and 6 as a program, and also stores data for various judgments and calculations in advance.
1 B, a microcomputer (hereinafter referred to as a microcomputer) 32 having RAM 31C as a work memory, etc.
It is composed of etc. Further, the idle switch 12A is connected to the input terminal P1 of the microcomputer 32. AFS
The output terminal 13 is connected to the counter 33 and the input terminal P3 of the microcomputer 32. 34 is the water temperature sensor 18 and A/D
An interface connected to the converter 35,
The output of the A/D converter 35 is configured to be input to the microcomputer 32. 36 is a waveform shaping circuit to which the output of the crank angle sensor 17 is input, and its output is input to the interrupt input terminal P4 of the microcomputer 32 and the counter 37. The output of the counter 37 is also connected to be input to the microcomputer 32. Further, 38 is a timer connected to the interrupt input terminal P5 of the microcomputer 32, and 39 is the battery voltage v.
1 is an A/D converter which converts the signal into digital data and inputs it to the microcomputer 32; 40 is a driver connected between the air conditioning switch 19 and the microcomputer 32; 43 is a timer provided between the microcomputer 32 and the driver 44;
The output of is connected to each injector 14. 45 is an interface to which the output of the crank angle sensor 17 is input, and the 10 signal which is the second pulse of the crank angle is sent to the timer 4.
Enter 6°47. The output of the waveform shaping circuit 36 and the output of the microcomputer 32 are also input to the timer 47, and the output is input to the reset terminal of the timer 46 and the D-F/F4B.
The output of the microcomputer 32 is also input to the timer 46, and the output is input to the set terminal of DF/F4B. D-F
The output of /F48 is sent to the ignition coil 22 via the driver 49.
is input.

Next, the operation of the above configuration will be explained. The output of the idle switch 12A is input to the input terminal PL of the microcomputer 32. The output of AFS 13 is input to a counter 33, which measures the period between rising edges of the output of AFS 13. The microcomputer 32 receives the rising edge of the output of the AFS 13 at an interrupt input terminal P3, performs interrupt processing every output pulse period of the AFS 13, and measures the period measured by the counter 33. Further, the output of the water temperature sensor 18 is converted into a voltage by an interface 34, converted into a digital value by an A/D converter 35 at predetermined time intervals, and is input to the microcomputer 32. The output of the crank angle sensor 17 is sent to the interrupt input terminal P4 of the microcomputer 32 via the waveform shaping circuit 36. It is input to the timer 47 and counter 37. The microcomputer 32 performs an interrupt process every time the output of the crank angle sensor 17 rises, and detects the period between these rises from the output of the counter 37. The timer 38 generates an interrupt signal to the interrupt input terminal P5 of the microcomputer 32 at predetermined intervals.

The A/D converter 39 A/D converts the battery voltage ■, and the microcomputer 32 takes in data on this battery voltage at predetermined time intervals.The air conditioning switch 190 on/off signal is input to the microcomputer 32 via the driver 40. be done. The timer 43 is preset by the microcomputer 32, and
The output capacitor P2 outputs a pulse of a predetermined width, and this output drives the injector 14 via the driver 44. Further, the microcomputer 32 sets the energization angle T' in the timer 46 and sets the ignition timing A in the timer 47.

In FIG. 1O, (a) is the crank angle signal of the crank angle sensor 17, (c) is the 1° signal of the crank angle sensor 17, (C) is the operating state of the timer 47, and (b) is the timer 4.
6 operating state, (e) is the Q output of DF/F48, (f
) respectively indicate the current flowing through the ignition coil 22.As shown in FIG.
Count the 1° signal output from D and when it reaches 0
-Output a signal to F/F48.

The timer 47 starts counting at the rising edge of the crank angle signal, and when it reaches O, resets the DF/F4B and cuts off the current to the ignition coil 22. Timer 46 is 0 when timer 47 is 0.
When the engine is in the wrong position, a countdown is started by a 1'' signal, and when it reaches 0, the D-F/F 48 is set and the ignition coil 22 is energized.

Next, the operation of the CPU 31A in the microcomputer 32 is shown in FIG.
This will be explained with reference to FIG. FIG. 3 shows the main program of the CPU 31A. When a reset signal is input to the CPU 31A, the RAM 31C1 input/output port etc. are initialized in step 100, the output of the water temperature sensor 18 is A/D converted, and the RAM 31C is is stored as WT. In step 102, the battery voltage V, is set to A
/D conversion and storage in RAM31C as VB. In step 103, 30/T is calculated from the cycle T8 of the crank angle sensor 17 to calculate the rotational speed Ne. In step 104, AN-Ne/30 is calculated from the load data AN and the rotational speed Ne, which will be described later, and the output frequency Fa of the AFS 13 is calculated. In step 105, the output frequency Fa
Therefore, as shown in FIG. 4, a basic driving time conversion coefficient of 7 is calculated from fl set for Fa. Step 10
In step 6, the conversion coefficient is corrected by 2 using the water temperature data WT, and the driving time conversion coefficient is set to 1 and stored in the RAM 31C. In step 107, the data table f3 stored in advance in the ROM 31B is mapped from the battery voltage data VB, and the wasted time T is calculated and stored in the RAM 31C. In step 108, the ignition coil 2 is turned on at the rotational speed Ne.
Calculate the conduction angle T, @ of 2, and in step 109 T' o
-=180- T oh is calculated, and T' DH is set in the timer 46 in step 110.

After the process in step 110, the process in step 101 is repeated again.

Figure 5 shows the interrupt input to the interrupt input terminal P3, that is, AFS13.
The interrupt processing for the output signal of is shown.

In step 201, the output Tv of the counter 33 is detected,
Clear counter 33. This T1 is the period between the rises of the output of the AFS13. In step 202, the period T
RAM31 where F is the output pulse period TA of AFS13.
In step 203, the integrated pulse data P
The remaining pulse data P is added to 7 to obtain new integrated pulse data P11. This integrated pulse data P1 is output from the AFS 13 during the rising edge of the crank angle sensor 17.
This is to integrate the number of output pulses of 1 of AFS13.
For convenience of processing, the pulse is multiplied by 156. In step 204, the remaining pulse data P.

is set to 156, and the interrupt processing ends.

FIG. 6(A) and FIG. 6(B) show the crank angle sensor 17.
In step 300, the period between the rises of the crank angle signal of the crank angle sensor 17 is read from the counter 37, and It is stored in the RAM 31C as periods T and l, and the counter 37 is cleared. At step 301A, the cycle T1 is added to the cycle integrated value TT to update Ti8 and store it in the RAM 31C.

In step 301B, 1 is added to the number of cycle accumulations N, and N
1 is updated and stored in the RAM 31C. Step 30
2, if there is an output pulse of the AFS 13 within the period T1, the time t of the immediately preceding output pulse of the AFS 13 is determined in step 303. The time difference Δt-tow-to+ between l and the current interrupt time tax of the crank angle sensor 17 is calculated, and this is set as the period T. If there is no output pulse of the AFS 13 within the period T, the period T1 is calculated in step 304. Let be period T. In step 305, 156 X T s/Ta
By calculating the time difference Δt, the time difference Δt is converted into the output pulse data ΔP of the AFS 13. That is, the pulse data ΔP is calculated assuming that the previous output pulse period of the AFS 13 and the current output pulse period of the AFS 13 are the same. Step 306
Then, if the pulse data ΔP is 156 or less, step 30
8, and if it is larger, ΔP is clipped to 156 in step 307. In step 308, the remaining pulse data PIl
The pulse data ΔP is subtracted from the pulse data ΔP to obtain new remaining pulse data PD.

In step 309, if the remaining pulse data PD is 0 or more, the process goes to step 313; otherwise, the pulse data ΔP
Since the calculated value of is larger than the output pulse of the AFS 13, the pulse data ΔP is made equal to P in step 310, and the remaining pulse data P is made zero in step 312. In step 313, the pulse data ΔP is added to the integrated pulse data P to obtain new integrated pulse data P, l. This data PI corresponds to the number of pulses that the AFS 13 is thought to have output during the current rise of the crank angle sensor 17. In step 314, the crank angle sensor 1
From the load data AN calculated up to the previous rise of 7, the integrated pulse data Pa, and the filter constants + and ki, calculate kl and 2·P for AN+, and use the results as the new load data AN. In step 315, if this load data AN is larger than a predetermined value α, it is clipped to α in step 316 to prevent the load data AN from becoming too large than the actual value even when the engine 1 is fully open. If so, proceed to step 317.

In step 317, the integrated pulse data pH is cleared.

In step 318, + is added to the load data AN and the driving time conversion coefficient, and driving time data T+-AN is calculated from the dead time Tll.
, ++To is calculated, drive time data T, is set in the timer 43 in step 319, and the timer 43 is triggered in step 320, so that four injectors 14 are simultaneously driven in accordance with the data T. Step 32
In step 1, the rotation speed N is calculated from T8 mentioned above, and in step 322, the ignition timing A is preliminarily stored in the ROM 31 based on AN and N.
It is obtained by remapping from the data table fs shown in FIG. 7 stored in B and stored in the RAM 31G.

In step 323, it is determined whether or not the above-mentioned period accumulation number Nm has reached 64. If it has not reached 64, the process proceeds to step 326, and if it has reached 64, in step 324, the above-mentioned period accumulation value T□ is set to mm. N-a = 30
/ (Ty * / 64) and calculate the average rotation speed N
, A are calculated and stored in the RAM 31C. Step 3
At step 25, Tt*-0 and Nm-Q are reset, and the process proceeds to step 326. At step 326, it is determined whether or not the load on the engine 1 has changed. This determination is made by, for example, reading a signal from the air conditioning switch 19 via the driver 40, setting a flag in response to the signal, and comparing the previous and current flag states to determine whether the state has changed from off last time to on this time. If the load changes, step 327 sets the delay time T, 1 second. However, this delay time T
For example, DL and t are subtracted by the predetermined time each time an interrupt is generated and processed by the timer 38 at predetermined time intervals. In step 328, it is determined whether the idle switch 12A is on or off. If it is off, the process proceeds to step 331. If it is on, it is determined in step 329 whether the delay time T mLV has become 0. If it is not 0, the process proceeds to step 331. 3
31, and if O, proceed to step 330. In step 330, A+GAX(N
, AN, ) and the calculated value is set as a new ignition timing A that is corrected. The relationship between the deviation ΔN=N, , -N and the idle ignition timing correction amount Ga x (N, , -N,) is as shown in FIG.

In step 331, the ignition timing A is set in the timer 47, and the interrupt processing is ended.

FIG. 9 shows the timing of the processing in FIG. 3 and FIGS.
[Yes]) indicates the crank angle signal of the crank angle sensor 17, (C) indicates the remaining pulse data P, and AFS13
For example, P□=P D 1 is set to 156 every time the output of the crank angle sensor 17 rises.
The calculation result is changed to 56 X T s / Ta. (A) shows the change in the integrated pulse data P, and the AFS
13 shows how the remaining pulse data PD is integrated every time the output of No. 13 rises.

In the above embodiment, the output pulses of the AFS 13 during the rising edge of the crank angle sensor 17 were counted, but this may also be done during the falling edge (or, the number of output pulses of the AFS 13 during several cycles of the crank angle sensor 17 may be counted). You can also
Although the output pulses of the AFS 13 are counted, the number of output pulses multiplied by a constant corresponding to the output frequency of the AFS 13 may be counted.

In addition, the relationships shown in Fig. 8 are mapped and stored in the ROM 31B, and the ignition timing correction amount at idle is calculated by mapping using the deviation ΔN (-N.-N,), and the ignition timing A is obtained. You can.

Furthermore, when determining whether or not the load has changed, a change in the load data AN may be detected (or a neutral safety signal of an automatic transmission may be detected, or a delay time T11 may be detected). Microcomputer 32 is used to measure Lv.
A dedicated timer may be provided externally, or the timer may be built into the microcomputer 32.

〔Effect of the invention〕

As described above, according to the present invention, when there is a change in the engine load, the ignition timing is not corrected based on the deviation between the average rotation speed and the instantaneous rotation speed for a predetermined period of time. Appropriate ignition timing can be set in response to load fluctuations, and the effect is that the desired rotation speed can be achieved quickly.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an ignition timing control device for an engine according to an embodiment of the present invention, FIG. 2 is a block diagram showing a specific embodiment of the ignition timing control device for the same engine, and FIG. A flowchart showing the main routine of the above device according to an embodiment of the present invention; FIG. 4 is a diagram showing the relationship between the basic drive time conversion coefficient and the AFS output frequency; FIGS.
) and FIG. 6CB) are flowcharts showing an interrupt processing routine for the operation of an engine ignition timing control device according to an embodiment of the present invention, FIG. 7 is a diagram showing an ignition timing map stored in a ROM, and FIG. FIG. 8 is an ignition timing correction amount characteristic diagram, FIG. 9 is a timing diagram showing the timing of the flows in FIGS. 5 and 6, and FIG. 10 is a timing diagram showing the on/off operation of the ignition coil. In the figure, 1...engine, 12...throttle valve, 13...AFS, 17...crank angle sensor, 1
9... Air conditioning switch, 20... AN detection means, 21
...Control means, 22...Ignition coil. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] a rotation signal generating means for generating a rotation signal according to the rotation speed of the engine; a rotation speed calculation means for inputting the rotation signal and calculating an instantaneous rotation speed and an average rotation speed; a load detection means for detecting the load of the engine; Ignition timing control means for controlling the ignition timing of the engine based on the engine load and instantaneous rotational speed; and correction means for correcting the ignition timing based on the deviation between the average rotational speed and the instantaneous rotational speed. The timing control device is characterized in that a load change detection means for detecting a change in the load of the engine is provided, and the correction means does not correct the ignition timing for a predetermined period of time from the time of detection by the load change detection means. Ignition timing control device for engines.