JPH0742914B2 - Ignition timing control device for internal combustion engine - Google Patents

Description

TECHNICAL FIELD The present invention relates to an ignition timing control device for an internal combustion engine, and more particularly to an ignition timing control device for an internal combustion engine that is effective when the vehicle is started or accelerated.

[Prior Art] The exhaust system of an internal combustion engine converts harmful components in the exhaust, that is, hydrocarbons (HC), carbon monoxide (CO), and nitric oxide (NOx) into harmless carbon dioxide, water, and nitrogen. For that purpose,
For example, a catalyst device such as a three-way catalyst is provided. In order to keep the exhaust gas purification rate of such a catalyst device good, it is necessary to keep the temperature of the catalyst at a temperature at which the catalyst is activated or higher. However, when the catalyst temperature is low, for example, when the internal combustion engine is stopped and left for a restart, or the like, the catalyst is not sufficiently activated, so the exhaust gas purification rate is significantly reduced. As a countermeasure against such a problem, conventionally, the ignition timing control of the internal combustion engine is performed, in which the cooling water temperature of the internal combustion engine is detected, and the ignition timing is controlled to the retard side during cold start based on the cooling water temperature. Devices and the like have been proposed. These devices control the ignition timing to the retard side so that slow combustion is performed in the expansion stroke, so that afterburn increases and the exhaust temperature rises, and the ignition timing is controlled to the retard side. As a result, the output of the internal combustion engine decreases, and the driver increases the throttle valve opening to increase the total amount of exhaust gas, which increases the temperature of the catalyst and promptly activates the catalyst. It is configured to improve exhaust characteristics.

[Problems to be Solved by the Invention] The ignition timing control device for an internal combustion engine as such a conventional technique has the following problems. That is, (1) When starting the vehicle, a larger torque is required to move the vehicle than when the vehicle is running steadily. However, since the ignition timing is controlled to the retard side, the torque of the internal combustion engine is low even when the throttle valve opening is increased. For this reason, in the case of a sudden start requiring a large torque, even if the throttle valve opening is increased, the output of the internal combustion engine is unstable and sufficient torque cannot be obtained. However, there is a problem in that it is difficult to connect the clutch and an internal load may stop due to an overload when the clutch is connected.

(2) Further, even when the vehicle accelerates from a state of traveling at an extremely low speed, the retard amount of the ignition timing is set to be the same as that in the steady traveling state. Therefore, similar to the case of (1) above. There is also a problem that the torque required for acceleration cannot be obtained even if the throttle valve opening is increased.

(3) As a measure against both of the above problems (1) and (2), for example, the ignition timing retard amount may be increased or decreased according to the rotation speed of the internal combustion engine. However, in the case of such a configuration, for example, the rotation speed of the internal combustion engine is set low and the gear ratio is set large, and when the vehicle is traveling steadily at a relatively high speed, the retard amount is set small. As a result, the temperature of exhaust gas and the total amount of exhaust gas decrease, and the catalyst cannot be activated.

(4) Furthermore, if the ignition timing retard amount is set so that a sufficient torque can be obtained at the time of starting, on the contrary, the catalyst cannot be sufficiently activated during steady running or high speed running. There were also problems.

It is an object of the present invention to provide an ignition timing control device for an internal combustion engine, which can obtain sufficient torque at the time of starting or accelerating from an extremely low speed and can preferably activate the catalyst during steady running.

Configuration of the Invention [Means for Solving the Problems] The present invention has the configuration illustrated in FIG. 1 in order to solve the above problems. FIG. 1 is a basic configuration diagram conceptually illustrating the content of the present invention. That is, the present invention, as illustrated in FIG. 1, includes an operating state detecting means M2 for detecting a load, a rotation speed and a temperature of the internal combustion engine M1, and an ignition timing retard value based on the temperature of the internal combustion engine M1. Calculating the basic ignition timing based on the retard value calculating means M3 and the rotation speed of the load detected by the operating state detecting means M2, and delaying the basic ignition timing by the retard value. An ignition timing control device for an internal combustion engine, comprising: an ignition control means M4 for controlling ignition of the internal combustion engine; and performing a temperature increase of an exhaust gas purifying catalyst by retarding a basic ignition timing. A vehicle speed detecting means M5 for detecting the vehicle speed of a vehicle driven by the engine M1, and a correction delay value for calculating a correction retard value by further reducing the above retard value as the vehicle speed decreases in accordance with the detected vehicle speed. The angle value calculating means M6 is provided, and Serial ignition control means M4 is one that summarized as ignition timing control apparatus for an internal combustion engine, characterized in that it is configured so as to retarded by the delay correction value in place of the retard value.

The operating state detecting means M2 is for detecting the load, rotation speed and temperature of the internal combustion engine M1. For example, the load is detected by measuring the intake air amount or the intake pipe internal pressure of the internal combustion engine M1, the rotation angle of the crankshaft of the internal combustion engine M1 or the camshaft of the distributor is detected, and the internal combustion engine is further detected. The temperature can be detected by measuring the cooling water temperature of M1.

The retard value calculating means M3 is for calculating the retard value of the ignition timing based on the temperature of the internal combustion engine M1, and a map or an arithmetic expression that defines the relationship between the cooling water temperature at that time and the retard value. The retard value is calculated from Further, as another method, the ignition retard value of the ignition timing is calculated based on the temperature of the internal combustion engine M1 at the time of starting, and further, the ignition retard value is gradually decreased as time elapses from the time of starting. Good.

The vehicle speed detecting means M5 is for detecting the vehicle speed of the vehicle driven by the internal combustion engine M1. For example, internal combustion engine
It is also possible to measure the rotation angle of the drive shaft that transmits the driving force of M1 to the drive wheels per predetermined time, and detect the vehicle speed of the vehicle based on the measured value.

The corrected retard value calculating means M6 calculates a corrected retard value which is the retard value calculated by the retard value calculating means M3, which is corrected to be smaller as the vehicle speed detected by the vehicle speed detecting means M5 is lower. It is a thing. For example, when the vehicle speed is equal to or lower than a predetermined value, the retard value may be reduced by a predetermined ratio to calculate the corrected retard value. Further, for example, the correction retard value may be calculated by decreasing the retard value according to a vehicle speed based on a predetermined function or map. Further, for example, it can be realized by various configurations such as subtracting a predetermined constant from the retard angle value to calculate the corrected retard value according to the vehicle speed.

The ignition control means M4 calculates the basic ignition timing on the basis of the load and the rotation speed detected by the operating state detecting means M2, and delays the basic ignition timing by the above-mentioned corrected retard value to change the internal combustion engine M1. It controls the ignition of. For example, the ignition control means M4, the retard angle value calculating means M3, and the corrected retard angle value calculating means M6 may be configured as independent discrete logic circuits. Further, it is configured as a logical operation circuit with ROM, RAM, and other peripheral circuit elements centering around a well-known CPU, and realizes each of the above means in accordance with a predetermined processing procedure, and calculates a delay angle value and a correction delay angle value. It may be one that controls ignition.

[Operation] In the ignition timing control device for the internal combustion engine of the present invention, as illustrated in FIG. 1, the retard value calculation means M3 causes the ignition timing to be calculated based on the temperature of the internal combustion engine M1 detected by the operating state detection means M2. Is calculated on the other hand, the ignition control means M4 calculates the basic ignition timing based on the load and the rotation speed detected by the operating state detecting means M2, and the basic ignition timing is set to the retard value only. When controlling the ignition of the internal combustion engine M1 by retarding, as the vehicle speed detected by the vehicle speed detecting means M5 is lower, the correction retard value which is further corrected by the correction retard value is further reduced. Further, the ignition control means M4 functions to retard the basic ignition timing by the corrected retard value instead of the retard value.

That is, when the vehicle speed of the vehicle driven by the internal combustion engine M1 is low, instead of the retard value determined by the temperature of the internal combustion engine M1, a control for retarding the ignition timing by a correction retard value smaller than the retard value. Is done.

Therefore, the ignition timing control device for an internal combustion engine of the present invention, the internal combustion engine M1 outputs a sufficient torque when the vehicle starts or accelerates from an extremely low speed, while maintaining a low rotation speed of the internal combustion engine M1 for steady running. If done, it works to raise the exhaust temperature. The technical problems of the present invention are solved by the action of each component of the present invention as described above.

[Embodiment] Next, a first embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 shows the system configuration of an engine equipped with the ignition timing control device for an internal combustion engine of the present invention.

As shown in FIG. 2, the engine 1 forms a combustion chamber 5 with a cylinder 2, a piston 3 and a cylinder head 4,
A spark plug 6 is arranged in the combustion chamber 5.

The intake system of the engine 1 includes an intake port 8 communicating with the combustion chamber 5 via an intake valve 7, an intake manifold 9 connected to the intake port 8, a surge tank 10 for absorbing pulsation of intake air, and intake air. A throttle valve 11 for adjusting the amount is provided.

On the other hand, in the exhaust system of the engine 1, an exhaust port 13 communicating with the combustion chamber 5 through an exhaust valve 12, and the exhaust port
Exhaust manifold 14 connected to 13 and exhaust manifold
An exhaust pipe 15 that guides exhaust from 14 and a three-way catalyst 16 that purifies harmful components in the exhaust are provided.

The fuel system of the engine 1 includes a fuel supply source including a fuel tank and a fuel pump (not shown), a fuel supply pipe, and a fuel injection valve 17 arranged near the intake port 8.

Further, the ignition system of the engine 1 distributes and supplies the igniter 18 that outputs a high voltage necessary for ignition, and the high voltage generated by the igniter 18 in conjunction with a crankshaft (not shown) to the ignition plugs 6 of each cylinder. It has a distributor 19.

Further, the output of the engine 1 is transmitted from a crank shaft (not shown) to a drive shaft (not shown) via the transmission 20.

The engine 1 is a throttle valve described as a detector.
An air flow meter 21 provided upstream of 11 for measuring the amount of intake air, an intake air temperature sensor 22 provided in the air flow meter 21 for measuring the intake air temperature, and an throttle valve 11 interlocked with the intake air temperature sensor 22. A throttle position sensor 23 for detecting the opening degree, a water temperature sensor 24 arranged in the cooling system for detecting the cooling water temperature, and an oxygen concentration sensor provided in the exhaust manifold 14 for detecting the residual oxygen concentration in the exhaust as an analog signal. 25 are equipped.

In addition, inside the distributor 19, a rotation angle that also functions as a rotation speed sensor that outputs a rotation angle signal every 1/24 rotation of the camshaft of the distributor 19, that is, every crank angle 0 ° to an integer multiple of 30 °. A sensor 26 and a cylinder discrimination sensor 27 that outputs a reference signal once for each rotation of the camshaft of the distributor 19, that is, for every two rotations of a crankshaft (not shown) are provided.

Further, inside the transmission 20, a vehicle speed sensor 28 that detects the vehicle speed by measuring the rotation speed of an output shaft that interlocks with a drive shaft (not shown) is provided.

The signals detected by the above sensors are input to an electronic control unit (hereinafter simply referred to as an ECU) 30, and the ECU 30 controls the engine 1 by driving the fuel injection valve 17 and the igniter 18 described above based on the signals. Do.

Next, the configuration of the ECU 30 will be described with reference to FIG. E
The CU 30 inputs and calculates each signal detected by each of the above-mentioned sensors in accordance with a control program, and performs the processing for controlling each of the above-described devices CPU 30a, the control program and the initial data RO are stored in advance.
M30b, RAM30c that temporarily stores various signals input to ECU30 and data necessary for arithmetic control, various data required for subsequent control of engine 1 even if the key switch of engine 1 is turned off by the driver Backup RAM 30d backed up by a battery so that it can be retained
It is configured as a logical operation circuit centered on
It is connected to the input / output ports 30f and 30g and the output port 30h via e to input / output with an external device.

The ECU 30 includes an air flow meter 21 and a water temperature sensor 2 as described above.
4. Buffers 30i, 30j, 30k for output signals from the throttle position sensor 23 are provided, and the multiplexer 30 selectively outputs the output signals of the above sensors to the CPU 30a.
m, A / D converter that converts analog signals to digital signals
30n is also provided. Each of these signals is input / output port 3
It is input to the CPU 30a via 0f.

Further, the ECU 30 has a buffer 30p for the output signal of the oxygen concentration sensor 25 described above, a comparator 0q that outputs a signal when the output voltage of the buffer 30p is equal to or higher than a predetermined voltage, the cylinder discrimination sensor 27 described above, and a rotation angle. It has a waveform shaping circuit 30r for shaping the waveform of the output signal of the sensor 26, and a counter circuit 30s for counting the number of output signals of the vehicle speed sensor 28, which has been described above. Each of these signals is sent to the CPU via I / O port 30g.
Input to 30a.

Further, the ECU 30 has the drive circuits 30t and 30u for supplying a drive current to the fuel injection valve 17 and the igniter 18, which have already been described, and the CPU 30
30a outputs a control signal to both drive circuits 30t and 30u via an output port 30h. The output port 30h has a CPU30
A compare A register and a compare B register for outputting an interrupt signal to the CPU 30a at a predetermined time set by a are provided. ECU30 is CPU30a
And a clock circuit 30v for sending a clock signal as control timing at a predetermined interval to the ROM 30b, the RAM 30c, and the like.

Next, each processing executed by the ECU 30 in the first embodiment will be described with reference to FIG. 4, FIG. 5, FIG. 6, FIG. 7, FIG.
This will be described based on the flowcharts shown in FIGS. 10, 11 and 12.

First, the engine control amount calculation process will be described with reference to FIG. This engine control amount calculation process is performed by the engine 1.
It is repeatedly executed every predetermined time with the operation of. In step 100, it is determined whether or not this process is the first time after the ECU 30 is started. If this processing is the first one, the routine proceeds to step 102, where initialization processing is performed. That is, each input / output port and output port described above
Initial reset of 30f, 30g, 30h is performed. Next, the process proceeds to step 104, the process of clearing the memory in the RAM 30c, the register set in the RAM 30c, the timer,
A process of setting initial data for flags, counters, etc. is performed. After the above steps 102 and 104 are completed, or if this processing is the second or later one, step 10
Go to 6. In step 106, the air flow meter 21 described above is used.
More processing is performed to detect the intake air amount, the intake air temperature from the intake air temperature sensor 22, the rotation angle from the rotation angle sensor 26, and the cooling water temperature THW from the water temperature sensor 24. In the following step 108, a process of calculating the intake air amount Q, the engine rotation speed Ne and the engine load Q / Ne is performed. That is, the intake air amount Q per unit time is calculated from the intake air amount and the intake air temperature detected in step 106, and the engine rotation speed Ne per unit time is calculated from the rotation angle. Here, the engine rotation speed Ne is calculated from the reciprocal of the interval of the output signal of the rotation angle sensor 26 stored in the RAM 30c. The engine load Q / Ne is calculated by dividing the intake air amount Q by the rotation speed Ne. Next, the routine proceeds to step 200, where ignition timing calculation processing is performed. Details of this ignition timing calculation processing will be described later. In the following step 300, the fuel injection time T [msec] is calculated as shown in the following equation (1).

T = (Q / Ne) x KB x Kt x (1 + Kp + Kw) (1) However, Q / Ne ... engine load [l / rev.] KB ... constant of fuel injection time corresponding to intake air amount Kt ... air-fuel ratio Feedback correction coefficient Kp ... High load increase coefficient Kw ... Correction coefficient based on cooling water temperature THW After that, the process goes to "NEXT" to end this processing.

After that, the engine control amount calculation process is repeatedly executed at predetermined time intervals as the engine 1 is operated.

Next, the input process will be described with reference to FIG. This input process is interrupted and executed each time A / D conversion is completed. In step 400, it is determined whether or not the current A / D converted value is the output signal of the water temperature sensor 24. If it is the output signal of the water temperature sensor 24, the process proceeds to step 410, and a process of storing the cooling water temperature THW in a predetermined area in the RAM 30c is performed. In the following step 420, the process of setting the flag Fthw to the value 1 is performed. Then, it progresses to step 440. The flag Fthw is reset to the value 0 in step 104 described above, and is set to the value 1 with the first A / D conversion of the output signal of the water temperature sensor 24 after the ECU 30 is started. On the other hand, if the signal other than the water temperature sensor output signal, that is, the A / D conversion of the output signal of either the air flow meter 21 or the throttle position sensor 23 is performed in step 400, the process proceeds to step 430. In step 430,
RAM 30 in which the A / D converted value of the intake air amount detected by the air flow meter 21 or the throttle valve opening detected by the throttle position sensor 23 is predetermined
After being stored in a predetermined area in c, the process proceeds to step 440. In step 440, after the process of starting the next A / D conversion is performed, the process returns to "RETURN" and the present process is terminated. Thereafter, this input processing is interrupted and executed every time A / D conversion is performed.

Next, the vehicle speed detection process will be described with reference to FIG. This vehicle speed detection processing is executed by interrupting every 4 [msec] after the ECU 30 is activated. In step 500, a process of adding 1 to the counter Cd is performed. The counter Cd is incremented every 4 [msec] to be 1 in the ignition timing calculation process described later.
This is a counter for measuring time up to [sec]. Next, in step 510, a process of detecting the count value of the counter circuit 30s counting the output signal of the vehicle speed sensor 28 is performed. In the following step 520, processing for calculating the vehicle speed V is performed. That is, the rotation speed of the drive shaft is obtained from the count value detected in step 510 and the time during which the count has been performed, and the vehicle speed V is calculated based on the rotation speed. Next, the routine proceeds to step 530, where the vehicle speed V calculated at step 520 is stored in a predetermined area in the RAM 30c. In the following step 540, after the process of resetting the counter circuit 30s counting the output signal of the vehicle speed sensor 28 is performed, the process returns to "RETURN" and the present process is terminated. After that, the vehicle speed detection process is executed every 4 [msec].

Next, the ignition timing calculation process executed in the above-described engine control amount calculation process will be described with reference to FIG. First, the outline of this processing will be described.

(1) The initial value of the ignition retard value θd is calculated (steps 202 to 214).

(2) The initial value of the retard value θd calculated in (1) above is set to 1
Advances by 0.1 [° C A] every [sec] (step 21)
6-224).

(3) A vehicle speed correction process is performed on the retard value advanced in (2) above (step 230).

(4) The basic ignition timing θb is calculated, and is corrected by the correction retard value θds calculated in (3) above to calculate the ignition timing θig (steps 240 and 250).

Next, details of this processing will be described. In step 202, the state of the flag Fthw is determined. If the first A / D conversion of the water temperature sensor output signal is performed after the ECU 30 is started, the flag Fthw is set to the value 1 in step 420 of the above-described input processing.
Is set to, the process proceeds to step 204. In step 204, the state of the flag Fd is judged. Flag Fd
Is a flag that is reset to a value 0 when the engine 1 is started, and is set to a value 1 once the initial value of the ignition retard value θd is calculated. This time, the flag Fd has a value of 0 at startup.
Since it has been reset to, the process proceeds to step 206. Note that once the initial value is calculated, the process proceeds to step 216 to avoid duplication of initial value calculation. In step 206, the process of setting the flag Fd to the value 1 is performed. In the following step 207, the cooling water temperature THW is 0.
It is determined whether the temperature is equal to or lower than [° C.]. Cooling water temperature THW
If is less than 0 [° C.], proceed to step 208,
After the processing for setting the initial value θd of the retard angle to 7 [° C A] (crank angle) is performed, the routine proceeds to step 216. on the other hand,
When it is determined in step 207 that the cooling water temperature THW exceeds 0 [° C.], the process proceeds to step 210. At step 210, it is judged if the cooling water temperature THW is lower than 70 [° C]. When the cooling water temperature THW is less than 70 [° C.], the routine proceeds to step 212, where after the process of calculating the initial value of the retard value θd by the following equation (2) is performed,
Continue to 216.

θd = 7−THW / 10 (2) On the other hand, in step 210, the cooling water temperature THW is 70.
When it is determined that the temperature is equal to or higher than [° C.] or when the flag Fthw is reset to the value 0 in step 202 described above, the process proceeds to step 214. In step 214, the process of setting the initial value of the retard angle value θd to 0 [° C A] (crank angle) is performed, and then the process proceeds to step 216. As described above, the initial value of the retard value θd and the cooling water temperature THW have the relationship shown in FIG. That is, when the cooling water temperature THW is 0 [° C] or less, the initial value of the retard angle value θd is 7 [° C A], and the cooling water temperature THW exceeds 0 [° C].
When the temperature is less than 0 [° C], the initial value of the retard value θd gradually decreases, and when the cooling water temperature THW is 70 [° C] or higher, the initial value of the retard value θd is 0 [° CA]. Therefore, the initial value of the retard value θd may be calculated based on a map that defines the relationship between the cooling water temperature THW and the initial value of the retard angle value θd as shown in FIG.

In step 216, it is determined whether or not the count value of the counter Cd is 250 or more. The value of the counter Cd is counted up every 4 [msec] in the vehicle speed detection processing described above.
Therefore, the value of the counter Cd becomes 250 or more when 1 [sec] has elapsed. The count is still insufficient and the value of the counter Cd
If less than 250, proceed to step 230. On the other hand, 1 [se
If c] has elapsed, proceed to step 218. Step 218
Then, a process of resetting the value of the counter Cd to 0 is performed. In the following step 220, a process of advancing the initial value of the retard value θd toward the advance side by 0.1 [° C A] (crank angle) is performed as shown in the following expression (3).

θd = θd-0.1 (3) In the following step 222, it is determined whether or not the retard value θd advanced in step 220 is negative. When the retard value θd is not negative, the routine proceeds to step 230. On the other hand, in step 220, the retard value θd is advanced too much, and the retard angle θd
If is negative, the process proceeds to step 224. In step 224, processing for setting the retard value θd to the value 0 is performed. In the following step 230, vehicle speed correction processing is performed.

The vehicle speed correction process will be described with reference to FIG. When the vehicle speed correction process is started, it is determined in step 230a whether the vehicle speed V is 10 [km / h] or less. In addition,
The vehicle speed V is calculated in the vehicle speed detection process described above. If the vehicle speed V is 10 [km / h] or less, step 23
The process proceeds to 0b and the retard value θd calculated in step 220 described above.
From this, a process for calculating the corrected retard value θds as in the following equation (4) is performed. Then, exit to "RETURN" and end the vehicle speed correction process.

θds = θd / 2 (4) On the other hand, when it is determined in step 230a that the vehicle speed V exceeds 10 [km / h], the process proceeds to step 230c, and the retard angle value θd calculated in step 220 described above. Is directly used as the corrected retard value θds. Then, exit to "RETURN" and end the vehicle speed correction process.

Next, in step 240 shown in FIG. 7, the basic ignition timing θ
The process of calculating b is performed. That is, the basic ignition timing θb is calculated from the ignition timing map stored in advance in the ROM 30b based on the load Q / Ne and the rotation speed Ne calculated in step 108 of the engine control amount calculation processing described above.
In the following step 250, a process of calculating the ignition timing θig is performed. That is, the corrected retard value θds calculated in step 230 and the basic ignition timing θ calculated in step 240.
The ignition timing θig is calculated from b and by the following equation (5).

θig = θb−θds (5) After that, the ignition timing θig is stored in a predetermined area in the RAM 30c, the process goes to “RETURN”, and the ignition timing calculation process ends. After that, the control shifts to the engine control amount calculation processing described above.

Next, the engine control process will be described with reference to FIG. This engine control processing is executed by interrupting the above-described engine control amount calculation processing by the pulse signal output from the rotation angle sensor 26 described above every time the crankshaft rotates 30 °.

In step 600, the process of calculating the rotation time is performed. That is, in order to calculate the engine rotation speed Ne, the time required for the rotation from the previous interruption of the crank angle 30 ° to the interruption of the current crank angle 30 ° is calculated. In the following step 602, the process of calculating the crank angle is performed.
That is, the crank angle at the time when this interrupt occurs is calculated based on the reference signal output from the cylinder discrimination sensor 27 described above. Next, the routine proceeds to step 604, at the time when this interruption occurs, whether or not the piston of either the first cylinder or the sixth cylinder has reached the top dead center and has reached the intake stroke. Is determined. If no cylinder has reached the intake stroke, the routine proceeds to step 610. On the other hand, if there is a cylinder that has reached the intake stroke, the routine proceeds to step 606.
In step 606, a process of opening the fuel injection valve 17 corresponding to the cylinder that has reached the intake stroke is performed. This allows
Fuel injection is started. In the following step 608, from the present time, step 30 of the engine control amount calculation process described above is performed.
A process of calculating the time t1 after the fuel injection time T calculated at 0 is calculated and setting the time t1 in the compare A register of the output port 30h is performed. The time t1 is the time at which the fuel injection valve 17 is closed. Then step 61
Go to 0.

In step 610, this interrupt is 9 crank angle before top dead center.
A determination is made as to whether or not it is a 0 ° interrupt. If the interrupt this time is not the crank angle before top dead center of 90 °, the routine proceeds to step 614. On the other hand, if the interrupt this time is an interrupt at a crank angle of 90 ° before top dead center, step 61
Go to 2. In step 612, the time t2 at which the igniter 18 cuts off the supply of the primary current based on the ignition timing θig calculated in step 200 of the engine control amount calculation process described above.
Is calculated and set in the compare B register of the output port 30h.

Next, the routine proceeds to step 614, where it is judged whether or not the interrupt this time is an interrupt of crank angle 60 ° before top dead center. If the interrupt this time is not an interrupt with a crank angle of 60 ° before top dead center, the process exits to "RETURN" and this process ends. On the other hand, if the interrupt this time is an interrupt for the crank angle before top dead center of 60 °, the process proceeds to step 616. Igniter in step 616
A process of calculating the time t3 at which 18 restarts the energization of the primary current and setting it in the compare B register of the output port 30h is performed. After that, the process exits to "RETURN" and this process ends. Thereafter, this engine control processing is started every time the crankshaft rotates 30 °.

Next, the fuel injection stop process will be described with reference to FIG. This fuel injection stop processing is performed at time t1 set in the compare A register in step 608 of the engine control processing described above.
And the time measured by the free-running timer match, the program is interrupted and executed. Step 700
Then, the process of closing the fuel injection valve 17 opened in step 606 of the engine control process described above is performed. This ends the fuel injection. After that, the process returns to "RETURN" and the fuel injection stop process is ended. Thereafter, this processing is executed by appropriately interrupting it as described above.

Next, the ignition process will be described with reference to FIG. This ignition process is interrupted when the time t2 set in the compare B register in step 612 of the above-described engine control process or the time t3 set in the compare B register in step 616 matches the time measured by the free running timer. Run on. In step 800, it is determined whether or not the interrupt this time is due to the coincidence with the time t2. If it is determined that the interrupt this time is due to the coincidence with the time t2, the process proceeds to step 802, where the igniter 18
Thus, the process of cutting off the energization of the primary current is performed. As a result, a high voltage is generated and ignition is performed. afterwards,
While exiting to "RETURN" and ending this processing, if it is determined in step 800 that the interrupt this time is due to coincidence with time t3, the process proceeds to step 804, in which the igniter 18 energizes the primary current. Processing for restarting is performed. This ends the ignition. Then, exit to "RETURN" and end this processing. After that, the ignition process is executed by appropriately interrupting the time as described above.

In the first embodiment, the engine 1 is the internal combustion engine M1 and the rotation angle sensor between the air flow meter 21 and the water temperature sensor 24 is used.
26, the ECU 30, and the processing executed by the ECU 30 (step 106) are the ECU 30 and the ECU 30 as the operating state detecting means M2.
Processing executed by (steps 202, 204, 206, 207, 208,
210,212,214,216,218,220,222,224) is the retard value calculating means M
As 3, the igniter 18, the ECU 30, and the processing executed by the ECU 30 (steps 250,610,612,614,616,800,802,80
4) functions as ignition control means M4. Further, the vehicle speed sensor 28, the ECU 30, and the processing executed by the ECU 30 (steps 510, 520, 530) are the vehicle speed detection means M5 and
Processing executed by the ECU 30 (steps 230a, 230b, 230
c) functions as the corrected retard value calculation means M6.

As described above, in the first embodiment, the retard value θd of the ignition timing is based on the cooling water temperature THW detected by the water temperature sensor 24.
The initial value of is calculated, and the initial value is 0.1 [° C] every 1 [sec].
A] (crank angle) is advanced, and the retarded value θd advanced further is 10 when the vehicle speed V detected by the vehicle speed sensor 28 is 10.
When [km / h] or less, the correction retard value θds reduced to 1/2 is calculated, and ignition is performed at the ignition timing θig at which the basic ignition timing θb is sent by the correction retard value θds. ing. Therefore, at the time of starting after cold restart of the engine 1 or when accelerating from an extremely low speed state, a correction that is half the retard value θd determined based on the cooling water temperature THW and the time after starting Since the ignition timing is retarded only by the retard value θds, the engine 1 can output a sufficient torque required for starting or accelerating, so that the engine 1 is stopped due to an overload when starting or accelerating. It is possible to quickly start and accelerate without causing any problems.

Further, when the vehicle speed V is 10 [km / h] or more, the corrected retard value θds is set equal to the retard value θd, so the ignition timing is sufficiently retarded and the exhaust temperature rises. Original catalyst 16
Can be quickly activated.

Next, a second embodiment of the present invention will be described. The difference between the second embodiment and the first embodiment is that the vehicle speed correction processing is different. Therefore, description of the system configuration and other processes is omitted, and the same portions or steps for performing the same processes are denoted by the same reference numerals.

The vehicle speed correction processing executed in the second embodiment will be described with reference to the flowchart shown in FIG. This vehicle speed correction processing is executed in step 230 of the ignition timing calculation processing described in the first embodiment. First, in step 230d, it is determined whether the vehicle speed V is 2 [km / h] or less. When it is determined that the vehicle speed V is 2 [km / h] or less, the routine proceeds to step 230e. In step 230e, the correction angle value θ
A process of calculating ds from the retard value θd as in the following equation (6) is performed.

θds = θd / 2 (6) After that, the process returns to “RETURN” and the present process ends. on the other hand,
When it is determined in step 230d that the vehicle speed V exceeds 2 [km / h], the process proceeds to step 230f. In step 230f, it is determined whether the vehicle speed V is less than 10 [km / h]. If the vehicle speed V is less than 10 [km / h], step 23
Go to 0g. In step 230g, a process of calculating the corrected retard value θds from the vehicle speed V and the retard value θd as in the following equation (7) is performed.

θds = θd × {(V−2) /16+0.5} (7) After that, the process returns to “RETURN” and the present process ends. on the other hand,
When it is determined in step 230f that the vehicle speed V is 10 [km / h] or more, the process proceeds to step 230h. Step
At 230h, processing for setting the corrected retard value θds equal to the retard value θd is performed. After that, the process returns to "RETURN" to end the vehicle speed correction process, and the control shifts to the ignition timing calculation process described in the first embodiment.

Note that, in the second embodiment, the ECU 30 and the processing executed by the ECU 30 (steps 230d, 230e, 230f, 230g, 230h)
Functions as the corrected retard value calculation means M6.

As described above, in the second embodiment, the vehicle speed V is 2 [km / h].
In the following range, the corrected retard value θds is set to 1/2 of the retarded value θd, while in the range where the vehicle speed V is 10 [km / h] or more, the corrected retarded value θds is set equal to the retarded value θd. However, the vehicle speed V is 2 [km
/ h] and less than 10 [km / h], the corrected retard value θds
Is gradually corrected from a half of the retard value θd to θd.

For this reason, the correction delay angle value θds is set small only when the vehicle speed is extremely low, and the correction delay angle value θds is increased as the vehicle speed increases, so that drivability during start / acceleration and activation of the catalyst It becomes possible to achieve both.

Further, since the correction retard value θds gradually increases as the vehicle speed increases, the change in the ignition timing becomes slow.
It is possible to maintain a good ride comfort without causing a drive surge due to a rapid change in the torque of the.

In the second embodiment, the corrected retard value θds is calculated from the retard value θd and the vehicle speed V using an arithmetic expression. However, the effect of the present invention can be obtained even if the correction delay angle value θds is calculated based on the map shown in FIG. 14 that defines the relationship between the vehicle speed V and the correction delay angle value θds.

Next, a third embodiment of the present invention will be described. The third embodiment is different only in the vehicle speed correction process, and the other configurations are the same as those in the first and second embodiments already described, and therefore the same portions or steps for performing the same processes are denoted by the same reference numerals. , Description is omitted.

The vehicle speed correction processing executed in the third embodiment will be described based on the flowchart shown in FIG. This vehicle speed correction processing is executed in step 230 of the ignition timing calculation processing described in the first embodiment. First, in step 230i, it is determined whether the vehicle speed V is 2 [Km / h] or less. If the vehicle speed V is 2 [Km / h] or less, step
Continue to 230j. In step 230j, the process of calculating the corrected retard value θds from the retard value θd as shown in the following equation (8) is performed, and then the process proceeds to step 230n.

θds = θd−4 [° C. A] (8) On the other hand, when it is determined in step 230i that the vehicle speed V exceeds 2 [km / h], the process proceeds to step 230k. Step
At 230k, it is determined whether the vehicle speed V is less than 10 [km / h]. When the vehicle speed V is less than 10 [km / h], the process proceeds to step 230m. At step 230m, a process of calculating the corrected retard value θds from the retard value θd as shown in the following equation (9) is performed, and then the routine proceeds to step 230n.

θds = θd-2 [° C A] (9) Next, in step 230n, the above step 230j or 230m
It is determined whether or not the corrected retard value θds calculated in step 1 is negative. If it is determined that the correction delay angle value θds is negative, the process proceeds to step 230p, and the correction delay angle value θds is set to 0 [° C.
[A] (crank angle) is set,
Exit to "RETURN" and end this processing. On the other hand, if it is determined in step 230n that the correction retard value θds is not negative, the process directly ends in “RETURN” and the present process ends.

On the other hand, if it is determined in step 230k that the vehicle speed V is 10 [km / h] or higher, the process proceeds to step 230q. In step 230q, the processing for setting the correction retard value θds to be equal to the retard value θd is performed, and then the routine returns to “RETURN” to end the vehicle speed correction processing. After that, the control shifts to the ignition timing calculation processing described in the first embodiment.

In the third embodiment, the ECU 30 and the processing executed by the ECU 30 (steps 230i, 230j, 230k, 230m, 230n, 230p, 23
0q) functions as the corrected retard value calculation means M6.

As described above, in the third embodiment, the vehicle speed V is 2 [km / h].
In the following cases, the retard value θd is 4 [° C A] (crank angle)
Corrected to the advance side, the vehicle speed V exceeds 2 [km / h] and 10 [km /
If it is in the range of less than h], the retard value θd is 2 [° C A]
(Crank angle) Corrected to the advance side, and the vehicle speed V is 10
In the case of [km / h] or more, the correction is performed so that the correction retard value θds is set equal to the retard value θd.
Therefore, especially when the retard value θd is small, the retard value θd
The correction retard value θds is largely corrected to the advance side as compared with the case where the is corrected to 1/2. Therefore, the torque of the engine 1 is increased and the cold start or acceleration from an extremely low speed state is performed. Can be done promptly.

Even if the cooling water temperature THW rises, the vehicle speed V is 10
When it is less than [km / h], the retard value θd is corrected to the advance side, so that the torque of the engine 1 is sufficiently secured, and the drivability is improved.

Although some embodiments of the present invention have been described above, the present invention is not limited to these embodiments and can be implemented in various modes without departing from the scope of the present invention. Of course.

EFFECTS OF THE INVENTION As described in detail above, the ignition timing control device for an internal combustion engine of the present invention calculates the retard value of the ignition timing based on the temperature of the internal combustion engine detected by the operating state detecting means. On the other hand, as the vehicle speed detected by the vehicle speed detection means is lower, the corrected retard value calculation means calculates the corrected retard value by further reducing the retard value, and the ignition control means is further operated by the operating state detection means. The basic ignition timing is calculated on the basis of the detected load and the rotational speed, and the basic ignition timing is retarded by the correction retard value to control the ignition of the internal combustion engine. Therefore, when the vehicle speed is low, such as when the vehicle is starting or accelerating from an extremely low speed state, the ignition retard value is set to a small value, and the internal combustion engine outputs sufficient torque. And the drivability can be maintained at a high level.

Further, when a large gear ratio is selected and steady running is performed at a high vehicle speed while keeping the rotation speed of the internal combustion engine relatively low, the ignition timing and the appropriate retardation are performed, so the exhaust temperature rises. Thus, the catalyst can be activated quickly.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram conceptually illustrating the content of the present invention, FIG. 2 is a system configuration diagram of the first embodiment of the present invention, and FIG.
Similarly, the drawings are block diagrams for explaining the configuration of the electronic control unit (ECU), and FIGS. 4, 5, 6, and 7 show the processing executed by the ECU in the first embodiment of the present invention. The flowchart shown in FIG. 8 is a graph showing a map defining the relationship between the retard value and the cooling water temperature, FIG. 9, FIG.
11 and 12 are flowcharts showing the processing executed by the ECU in the first embodiment of the present invention, FIG. 13 is a flowchart showing the processing executed by the ECU in the second embodiment of the present invention, and FIG. FIG. 15 is a graph showing a map defining the relationship between the corrected retard value and the vehicle speed, and FIG. 15 is a flowchart showing the processing executed by the ECU in the third embodiment of the present invention. M1 ...... Internal combustion engine M2 ...... Operating state detection means M3 ...... Delay angle value calculation means M4 ...... Ignition control means M5 ...... Vehicle speed detection means M6 ...... Corrected delay angle value calculation means 1 ...... Engine 18 ...... Igniter 21 …… Air flow meter 24 …… Water temperature sensor 26 …… Rotation angle sensor 28 …… Vehicle speed sensor 30 …… Electronic control unit (ECU)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Osamu Harada 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (56) Reference JP 57-51954 (JP, A) JP 58-185976 (JP, A)

Claims (1)

[Claims] 1. An operating state detecting means for detecting a load, a rotational speed and a temperature of an internal combustion engine, a retard value calculating means for calculating a retard value of an ignition timing based on the temperature of the internal combustion engine, and the above operation. Ignition control means for controlling the ignition of the internal combustion engine by calculating the basic ignition timing based on the load and the rotation speed detected by the state detecting means, and delaying the basic ignition timing by the retard value. In the ignition timing control device for an internal combustion engine, which is configured to raise the temperature of the exhaust gas purifying catalyst by retarding the basic ignition timing, a vehicle speed detecting means for detecting a vehicle speed of a vehicle driven by the internal combustion engine. A correction retard value calculating means for calculating a correction retard value in which the retard correction value is corrected to be decreased as the vehicle speed is lower, in accordance with the detected vehicle speed, and the ignition control means is further provided with: Instead of the retard value An ignition timing control device for an internal combustion engine, which is configured to retard the corrected retard value.