JPS63134859A - Ignition control device for internal combustion engine - Google Patents

Abstract

PURPOSE:To make a program simpler and operating time shorter, and obtain an ignition control device which can be easily corrected at the time of transient rotational change by making the operations of ignition time and of turning on electricity time only on the basis of time information. CONSTITUTION:MPU 13 receives a signal (the number of pulses formed of ignition period equally divided by Z<n>) from a rotating angle sensor 5 and a signal from a reference position sensor 6 or the like through an input buffer 12, and required time TINT for ignition period is determined on difference in the time of angular pulse at the positions of last and present an upper dead center in a cylinder, and ignition time TSPK is obtained by map retrieval on the state of engine operation, and moreover turning on electricity time TON is determined on battery voltage and rotating speed. Then, angular pulse period can be simply obtained by shifting (n) times the data of the ignition period time determined from residual time subtracted the times TSPK, TON from the time TINT, and a rotating angle position can be determined on the basis of the time. Since the operations of the ignition time and of the turning on electricity time can be made only on the basis of time information, a program can be simply formed, and operation time can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ignition control device for an internal combustion engine that mainly uses a microcomputer to control the ignition of the engine.

[Prior Art] Conventionally, a microcomputer is equipped with a reference position sensor that detects the vicinity of top dead center of an internal combustion engine, a rotation angle position sensor that generates equally spaced pulses in synchronization with the rotation of the crankshaft, and , a device that calculates the ignition timing and energization time using a load condition sensor that detects the amount of intake air, etc. as input, and outputs the ignition signal is being considered (for example, Nippondenso Publication Technique Reference Number 37-062 1' 9, 984
(published on the 15th of the month).

[Problem that the invention seeks to solve]

However, in the conventional device described above, since the generation position and interval of the angular position signal of the rotational angular position sensor are angular information, they are calculated based on the ignition angle and the energization angle, and the timing to be processed is determined, and the angular information is The program is not only complicated because it converts into time and outputs it, but also requires a long calculation time.Furthermore, it is difficult to make corrections when there is a transient change in rotation. .

Therefore, the present invention not only simplifies programming, but also
The purpose of this invention is to shorten the performance time and also to be able to easily make corrections when there is a transient change in rotation.

[Means for solving problems]

Therefore, as shown in FIG. 1, the present invention includes a reference position sensor that generates a signal at a reference angular position of an internal combustion engine, a rotation angle sensor that generates a rotation angle pulse that equally divides the ignition period of the internal combustion engine into 2'', ignition calculation means for calculating the ignition timing and energization time in terms of time; ignition period calculation means for calculating the required ignition cycle time according to the output signal of the reference position sensor; An angular pulse cycle calculating means for calculating the required rotation angle pulse cycle time, and calculating the rotation immediately before the energization start time from the magnitude of the remaining time obtained by subtracting the ignition timing and energization time calculated by the ignition calculation means from the ignition cycle time required. An angular position time calculation means immediately before energization that calculates the angular position from the rotational angle pulse period required time calculated by the angle pulse required time calculation means, and energization starts from the immediately before energization rotational angular position calculated by the angular position time calculation means immediately before energization. energization remaining time storage means for storing the remaining time until the current energization time, and energization start signal generating means for generating the energization start signal after the remaining time from the previous rotation angle position has elapsed according to the remaining time stored in the energization remaining time storage means. and a rotational angle pulse obtained by calculating the rotational angle displacement 1 immediately before the ignition timing by the angle pulse required time calculation means from the magnitude of the remaining time obtained by subtracting the ignition timing calculated by the ignition calculation means from the ignition cycle required time. An angular position time just before ignition calculation means that calculates from the period required time, a remaining ignition time storage means that stores the remaining time from the last rotational angular position calculated by the angular position just before ignition time to the ignition timing; To provide an ignition control device for an internal combustion engine, comprising an ignition timing signal generation means for generating an ignition timing signal after the elapse of the remaining time from a rotation angle position immediately before ignition according to the remaining time stored in a remaining ignition time storage means.

[Operation] As a result, the angular pulse period can be easily determined by shifting the ignition cycle time data 0 times, and the rotational angular position can be determined based on time, and the ignition timing and energization time can be calculated using only time information. It can be executed with

〔Example〕

The present invention will be described below with reference to embodiments shown in the drawings.

Figure 2 shows the connection configuration of the entire control device.
10 is a control unit main body, which is a micro processing unit (hereinafter referred to as MP) that constitutes a microcomputer.
(abbreviated as U) 13 to determine the operating state of the internal combustion engine, select the ignition timing corresponding to the operating state stored in advance, and supply the ignition signal to the electronic switch 20 via the output buffer 14. It is.

30 is an ignition coil, the common terminal of the primary and secondary coils is connected to the DC power supply +V, the other end of the primary coil is connected to the electronic switch 20, and the other end of the secondary coil is connected to the DC power supply +V. is connected to the spark plug via a high-pressure distributor (not shown).

Reference numeral 11 denotes an analog-to-digital converter (ADC) that converts an analog input voltage into a digital value, and is configured to communicate the digital conversion result to the MPU 13.

In addition, there is an intake air amount sensor 1 that detects the intake air amount of the internal combustion engine by combining a displacement plate and a potentiometer, a battery voltage detection circuit 2 that detects the voltage of the battery power terminal, and a throttle opening sensor that has a potentiometer installed on the rotating shaft of the throttle valve. The analog input signal terminal of sensor 4, cooling water temperature sensor 3, which combines a thermistor and reference resistance, etc. is ADCII.
Connect to the input end of the

I2 is an input buffer that converts the level of digital input voltage, and a rotation angle sensor 5 that generates pulses in synchronization with the rotation angle of the crankshaft. A reference position sensor 6 that generates pulses is connected to the voltage level signals of various switches 7 (idle, air conditioner, valve, etc.).
The configuration is such that the voltage level is converted and supplied to the U13 standard.

The rotation angle sensor 5 calculates the ignition period, which is a value obtained by dividing 720° CA by the number of cylinders in the case of a 4-cycle engine, and 180° CA in the case of a 4-cylinder engine, which is a pulse equally divided by 2'' (n = 2). It is structured so that it becomes a number.

In the above configuration, the MPU 13 determines the operating state of the internal combustion engine, calculates the ignition timing, and outputs the ignition signal according to the result.
This will be explained using the timing chart in Figure 5.

FIG. 4 is a timing chart at low speed steady state, and 6S indicates the edge output position of the reference position sensor 6, which is near just before the TDC of each cylinder.

5S indicates the output position of the edge of the rotation angle sensor, and the ignition period is divided equally into 22, one pulse of which is TD.
It is arranged to show the vicinity of C.

The MPU 13 stores the time point when the pulse from the rotation angle sensor 5 is input after receiving the pulse from the reference position sensor 6 as the top dead center position, and calculates the ignition signal according to the flowchart in FIG. 3(A).

In step 101, the required ignition cycle time TINT is determined from the difference between the time of the angle pulse at the previous top dead center position and the time of the angle pulse at the current top dead center position, and in step 102, the optimum time TINT is determined in advance according to the rotational speed and load. Determine the ignition timing, convert it into advance or delay time from top dead center position, and select the value stored in the map according to the driving condition to set the ignition time T.
. In step 104, TI is calculated from the remaining time obtained by subtracting T, PK, and T from T and HT obtained earlier.
N? Subtract ÷2z from the value obtained as one pulse interval by lowering the binary data of TIN〒 twice (shifting it to the right), find a range that does not become negative, and calculate the top dead center of the rotation angle pulse. CCRK expressed as the number of times from the position is normally stored as the immediately preceding processing angle. In addition, the ignition immediately preceding processing angle is also determined in the same manner. At 105, each processing angle CCRK
The remaining time required for energization and ignition are respectively stored as TDLV. At this time, if the absolute value of T DLV is shorter than the time required to execute the program T'', 4sx, 1
Add the pulse interval time and correct the CCRK. In this way, all calculations related to ignition signal processing are performed using time data, and the pulse interval is equally divided by 2'', thereby simplifying the program.

In Fig. 4, CMP means that when the time latched at the time of inputting the angle pulse is the energization start time or the immediately preceding processing angle CCRK time with respect to the ignition time, the TDLv is OCR (output conveyor register). It shows the difference time between the value to be set and the subsequent TC (free run timer counter), and if the OCR contents match, the preset output level is set to the output port,
This shows that it is possible to create an ignition signal like 01JT.

Next, the acceleration from low speed will be explained with reference to the timing chart of FIG. 6S and 5S are similar to those shown in FIG. 4, but the pulse interval changes due to acceleration. When the next pulse from the rotation angle sensor 5 of the TDC is input, as shown in Fig. 3 (
Correct calculation of the energization start timing is performed according to the flowchart in B). At step 201, the pulse period required time T□N1 is determined from the difference between the angle pulse time at the previous top dead center position and the current angle pulse input time, and at step 210, it is determined whether the position is the next nine degrees from the top dead center. , to other routines if they are different. If it is the angular position next to the top dead center, the state of the output port is checked at 220, and if it is already energized, that is, if it is in a state of high speed rotation, it passes to another routine. In 221, TPINTi before 1 ignition and T this time...4Ai+1
Find the time difference T DLY.

222, Tl1lL obtained earlier, Tl1lLvx
Subtract CCRK to find T'nty', and calculate this TDLV
' is stored and updated in place of TDt,Y. At 230, it is determined whether the updated T_DLY is positive or negative, and if it is positive, it is passed as a bus. If negative, set TPIN to updated T DLV with 231
Add Ti and l to find T'oty'' and CC
The RK is modified and stored one position earlier, and the storage is updated again with TDLV' as ToLv. In this way, the energization time can be secured with a simple processing program even when the speed changes during acceleration.

In addition, in order to more accurately correct the acceleration of the energization time,
In the flowchart of FIG. 3(B), at 221, T
, L, is further divided by 2fi to find the time difference T, L, ' per one rotation angle pulse, and at 222, T from TDLY.
Subtract DLV +TDLT' X (CCRK 1) and get T. Find LV' and convert this T'ot,v' to TD
Memory updating may be performed instead of L7.

Further, in the above-described embodiment, the reference position sensor 6 is located at a position for determining the TDC of each cylinder, but it is sufficient if it can determine a predetermined, guaranteed angular position. Alternatively, a configuration may be adopted in which a predetermined angular position of a specific cylinder is determined.

Furthermore, although the rotation angle sensor 5 divides the ignition period into four equal parts in the illustrated example, calculation is easy if the ignition period is divided into eight or sixteen equal parts, so it may be divided into 21'1 equal parts.

Furthermore, although the configuration is such that the acceleration is corrected only once per ignition cycle, the acceleration may be corrected two or more times, but the program load increases.

Further, in the above-described embodiment, correction during acceleration is performed only at the energization start time, but correction may also be performed on the ignition timing during acceleration.

〔Effect of the invention〕

As described above, in the present invention, the angular pulse period can be easily determined by shifting the ignition cycle time data 0 times, the rotational angular position can be determined by time, and the ignition timing and energization time can be calculated. Because it can be executed using only time information, the program is simple and the calculation time can be shortened, and it also has the excellent effect of being able to easily make corrections in the event of transient rotational fluctuations. be.

[Brief explanation of the drawing]

FIG. 1 is a diagram corresponding to the claims of the present invention, FIG. 2 is a block diagram showing an embodiment of the device of the present invention, and FIG. 3(A),
(B) is a flowchart for explaining the operation of the MPU shown in FIG. 2, and FIGS. 4 and 5 are timing charts for explaining the operation of the device shown in FIG. 2. 5... Rotation angle sensor, 6... Reference position sensor, 1
3...MPU, 20 that constitutes a microcomputer
...Electronic switch, 30...Ignition coil.

Claims (1)

[Claims] A reference position sensor that generates a signal at a reference angular position of the internal combustion engine, a rotation angle sensor that generates a rotation angle pulse that divides the ignition cycle of the internal combustion engine into 2^n equal parts, and a time-based calculation of ignition timing and energization time. ignition calculation means; ignition period calculation means for determining the required ignition cycle time according to the output signal of the reference position sensor; and an angle pulse for determining the rotation angle pulse period time by shifting the ignition cycle time n times. cycle calculation means; and the angle pulse required time calculation means, which calculates the rotation angle position immediately before the energization start time from the magnitude of the remaining time obtained by subtracting the ignition timing and energization time calculated by the ignition calculation means from the ignition cycle time. An angular position time calculation means immediately before energization is calculated from the rotational angle pulse period required time determined by the energization immediately before energization angular position time calculation means, and an energization method that stores the remaining time from the immediately preceding rotational angular position calculated by the angular position time immediately before energization calculation means to the time when energization is started. remaining time storage means; energization start signal generating means for generating an energization start signal after the remaining time from the immediately preceding rotation angle position has elapsed according to the remaining time stored in the energization remaining time storage means; An angular position time immediately before ignition calculated from the rotational angle pulse period required time determined by the angle pulse required time calculation means to calculate the rotational angle position just before the ignition timing from the remaining time after subtracting the ignition timing calculated by the calculation means. a calculation means, a remaining ignition time storage means for storing the remaining time from the immediately preceding rotational angular position to the ignition timing obtained by the immediately before ignition angular position time calculation means, and a remaining time stored in the remaining ignition time storage means. ignition timing signal generating means for generating an ignition timing signal after the remaining time from the rotation angle position just before ignition has elapsed according to the ignition timing signal generation means for an internal combustion engine.