JPS6123868A - Ignition-timing controller - Google Patents

Abstract

PURPOSE:To avoid the knocking on acceleration and prevent the deterioration in the acceleration feeling by correcting the value of the load according to the acceleration degree, in an apparatus for calculating the ignition timing according to the number of revolution of an engine and the load. CONSTITUTION:A load correcting means IV corrects the load detected by a load detecting means II according to the acceleration degree and forms load information. An ignition-timing calculating means V calculates the ignition timing of an engine according to the number of revolution detected by a revolution-speed detecting means I and the load of a load correcting means IV. An ignition means VIexecutes ignition in an engine VII at the ignition timing. Therefore, the knocking on acceleration can be properly avoided, and the deterioration in acceleration feeling can be obviated.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a device for controlling the ignition timing of an internal combustion engine according to the rotational speed and load, and particularly to a device for controlling the ignition timing during transient periods. .

(Prior art) Conventionally, the device disclosed in, for example, Japanese Patent Application Laid-Open No. 57-99269, detects acceleration using an acceleration signal and calculates the amount of retardation, in order to avoid the knock-off during acceleration. This method is used to calculate the final advance angle value, but this method retards all angles when accelerating even outside the knock area, resulting in a corresponding drop in output and the problem of impairing the acceleration feeling outside the knock area. .

As a countermeasure against this, for example, it is necessary to have a map of the amount of retardation for each engine speed and load. In addition, in the case of a full range delay angle, the angle may be further delayed than the slowest value of the map, and it is possible that the withstand voltage of the distributor may be exceeded. In this case, it is necessary to take measures such as providing a guard for the retard angle amount or providing a guard for the final advance angle value.

As described above, the conventional method requires complicated control.

(Purpose of the Invention) Therefore, the present invention detects the degree of acceleration based on the amount of change in the throttle valve opening, the amount of asynchronous injection, etc., and determines the ignition timing based on the detected degree. By correcting the value of the load, which is one of the parameters in Decision 5, it is possible to easily avoid non-king during acceleration without unnecessarily retarding the engine and impairing drivability such as acceleration feeling. It is an object.

(Configuration of the Invention) FIG. 1 is an overall configuration diagram for clearly showing the configuration of the present invention. ■ is a rotation speed detection means for detecting the engine rotation speed, H
1 is a load detection means that detects the engine load based on the amount of intake air, etc., 2 is an acceleration detection device that detects the engine acceleration based on the throttle valve opening, etc., and 2 is a load detection device that converts the load detected by the load detection device into an acceleration. This is a load correction means that corrects the load information accordingly and uses it as new load information. Also, ■ is an ignition timing calculation means for calculating the ignition timing of the engine according to the rotation speed detected by the rotation speed detection means and the load from the load correction means;
is the igniter that ignites the engine ■ at this ignition timing,
Ignition means such as an ignition coil.

(Embodiment) FIG. 2 is an overall configuration diagram showing an embodiment of an ignition timing control device according to the present invention. Reference numeral 1 is a rotation angle sensor using an electromagnetic big amplifier, etc., which is attached to the crankshaft or camshaft so as to generate an output synchronized with the rotation of the crankshaft, and transmits engine rotational speed information to the engine control unit) 4. (referred to as f&ECU). Reference numeral 2 denotes an air flow meter that detects the intake air amount of the engine, which is a sensor that detects the load condition of the internal combustion engine, and inputs its output to the ECU 4. Numeral 3 denotes sensors such as a water temperature sensor, an intake temperature sensor, a pressure sensor, and a throttle sensor that detects the opening degree of the throttle valve, which detects the operating state of the engine and inputs the output to the ECU 4.

4 is an ECU that inputs the outputs of the rotation angle sensor 1, air flow meter 2, and other sensors R3, and performs waveform shaping and A
It is composed of an input processing section 41 that performs /D conversion, etc., a microcomputer 42, and an output processing section 43. An igniter 5 turns off a power transistor for controlling the primary current of an ignition coil (not shown). Reference numeral 6 denotes an ignition coil that receives the output of the igniter 5 and generates a high voltage to cause a spark to fly to a spark plug (not shown). 7 is an injector that injects fuel in response to an injection signal from the ECU.

In addition, the fuel injection amount of the injector and the igniter 5
The timing for turning off the power transistor (ignition timing) is calculated and determined by the microcomputer 42 based on information from the rotation angle sensor 1, air flow meter 2, and other sensors 3.

Next, the operation of the apparatus configured as described above will be described.

In the steady operating state, the microcomputer 4
Due to the delay in calculation processing and the delay in the response of each sensor, knocking will not occur in the engine, but during acceleration, racing, etc., knocking may occur due to the delay in calculation processing and the delay in the response of sensors. If this occurs and the intensity is strong, it not only causes discomfort to the driver but also adversely affects the durability of the engine.

Conventionally, in order to avoid knocking during this transient period, a method has been adopted in which the acceleration time is detected and the ignition timing is retarded by, for example, a predetermined period of time or a predetermined number of ignition times. .

An example is shown in FIG. In this figure, A is the ignition signal input to the igniter, B is the idle switch signal, and C is the ignition timing calculation value with the vertical axis being the advance amount. This method detects that the idle SW signal is turned OFF during sudden acceleration or racing from an idle state, or when accelerating from a decelerated state, and retards the ignition timing by a predetermined value for a predetermined time or a predetermined number of ignition times. In this method, the amount of retardation or the number of retard ignitions is constant regardless of the degree of acceleration, so non-king can be avoided in the knocking region, but outside the non-king region, the torque may decrease and the acceleration feeling may deteriorate. There is a problem of damaging the In addition, the ignition timing may be further retarded than the maximum retard value of the ignition timing map, and the withstand voltage of the distributor may be exceeded, or the required voltage of the engine may become greater than the generated voltage, resulting in a misfire.

In addition, in order to solve the problem of spoiling the acceleration feeling, a map of retardation amount is provided for each engine speed and load, and in areas where knocking is large, the retardation amount or number of retard ignitions is increased. , 7, and 7, it is necessary to reduce the retard amount or the number of retard ignitions.

In addition, in order to solve the problem of overvoltage withstand or misfire occurrence, it is necessary to take measures such as setting a guard on the retard amount or setting a guard on the final calculated value, but both of them make the program complicated. There are drawbacks.

Furthermore, knocking is detected using a non-knock sensor, etc.
Even if a method of retarding the ignition timing by feedback is used, the first knock tip during this transition cannot be avoided in principle.

In order to solve these problems as described above, the present invention detects the degree of acceleration by, for example, the differential value of the flow/7 torque valve opening in a method that determines the ignition timing based on the engine speed and load. This is an ignition timing control device during a transient period that easily avoids non-king and does not impair driveability by correcting load information, which is one of the parameters for determining ignition timing, depending on the degree of acceleration each time.

FIG. 4 shows a timing chart of transient ignition timing control according to the present invention. In this figure, F is the output VTH of the throttle sensor that detects the opening degree of the throttle valve. V
TH is a signal obtained by converting the throttle opening into an analog output. G is a fuel injection signal, which is controlled to achieve the optimum injection amount by synchronous injection a, which is calculated once every two ignitions, and asynchronous injection a, which is calculated every 4 ms cycle. ■
] is the count value TAIN of the asynchronous injection pulse counter
At J, the value in the pulse is added each time an asynchronous injection is executed, and is cleared when the next synchronous injection is executed.

(2) is the intake air amount 'rp per crank rotation calculated based on the outputs of the rotation angle sensor and the air flow meter, and indicates the load state of the engine. Ignition timing and fuel injection amount are calculated based on this 'rp and rotation speed information input from the rotation angle sensor. J is the load calculation value for ignition timing calculation, which is the key point of the present invention, and is the intake air amount Tp that cannot provide an accurate response during transient times (when the throttle valve is opened).
The load calculation value is corrected by adding TAINJ to .

Now, when accelerating or racing from a steady state, the idle switch signal shifts from ON to OFF and the throttle valve opening changes, so asynchronous injection is executed based on the differential value. Count the asynchronous injection and TAI
Create NJ and use it as the load correction amount at the time of transient, add it to the calculated load 'rp and use it as the load information of the transient piece, and perform map interpolation of the ignition timing using the load information using the engine speed information NE to find the optimal value at the time of transition. Find the ignition timing.

FIG. 5 shows the relationship between the differential value of the throttle valve opening and TAINJ. TAINJ is in direct proportion to the throttle valve opening differential; when the throttle valve is opened rapidly, the value of TAINJ becomes large, and when the throttle valve is opened slowly, the value of TAINJ becomes small.

Therefore, in the case of sudden acceleration, the load is largely corrected to the high load side, and in the case of slow acceleration, the correction amount becomes smaller. As the engine load increases, the required ignition timing shifts to the retarded side, and if we consider that the combustion speed is the same at low and high engine speeds, the required ignition timing will advance at the same load at high engine speeds than at low engine speeds. It is a well-known fact that the ignition timing map is set to be more advanced at high revolutions than at low revolutions under the same load.

Also, even at the same rotation speed, the high load side is set to the retard side, and the low load side is set to the advance side.

Therefore, when transient knocking is most likely to occur, it is most retarded during sudden acceleration from low revolutions or sudden racing, and when sudden acceleration from medium to high revolutions or rapid lasing is the most retarded, and when rapid acceleration from medium to high revolutions or racing is the most retarded. Sometimes the amount of retardation becomes small.

Furthermore, the amount of retardation is smaller in slow racing and slow acceleration than in sudden acceleration and fast racing.

Flowchart 1 for detailed explanation of the present invention is shown in FIG.
・Indicates. First, initialization is performed in step 11, and the process moves to step 12. In step 12, if the engine rotational speed signal is to be taken in (every 180'CA), the engine rotational speed signal is taken in, and in step 13, the rotational speed NE is calculated, and the process proceeds to the next step. If the rotation speed signal is not captured, the process moves to step 14, and the intake air amount intake timing (if 360° CA@≧, the capture is performed, step 15 calculates Tp, and step 16 calculates the asynchronous injection count value TAIN.
Clear J and proceed to the next step. If it is not the timing to take in Tp, jump to step 17. In step 17, the calculation timing of the ignition timing θ (180° CA
), the process moves to step 18, where Tp and TArNJ are added to obtain load information TPX. Next, in step 19, map interpolation is performed using the load information TPX and engine speed NE to calculate the ignition timing, and the process moves to step 20. Calculate the ignition timing θ. If the timing is not correct, jump to step 20.

In step 20, it is determined from the input of the acceleration signal from the throttle valve opening whether or not the asynchronous injection is to be executed.If it is determined that the asynchronous injection is to be executed, the asynchronous injection amount is calculated in step 21, and the process moves to step 22. In step 22, an asynchronous injection count value (load correction amount) is set in TAINJ, and in step 23, processes such as synchronous injection, ignition, and asynchronous injection are performed, and the process moves to step 12. If the determination in step 20 is negative, the process jumps to step 23.

In the above flowchart, when acceleration is detected in step 20, the asynchronous injection count value is set to TAINJ in step 22, and then, when the process moves to step 18, the load information for ignition timing calculation is set to TPX. TP and TA
Cent the transient load information with INJ added. Then, in the next step 19, map interpolation of the ignition timing is performed using the engine speed NE and the transient load information TPX, and in the next step 23, ignition processing is performed using the corrected ignition timing.

(Effects of the Invention) As described above, the present invention is capable of correcting the value of the load, which is a parameter for determining the ignition timing, according to the degree of acceleration in a device that calculates the ignition timing according to the engine speed and the load. This has the excellent effect of appropriately avoiding knocking during acceleration, preventing torque reduction due to unnecessary retardation, and avoiding deterioration of acceleration feeling.

[Brief explanation of the drawing]

Figure 1 is an overall configuration diagram for explaining the configuration of the present invention, Figure 2
3 is a timing chart showing an example of conventional ignition timing control. FIG. 4 is a multi-timing chart showing each timing of ignition timing control of the present invention. Figure 5 shows the throttle valve opening differential value and TAIN.
FIG. 6 is a flowchart showing the ignition timing control procedure of the present invention. 1... Rotation angle sensor, 2... Air flow meter, 3...
...Sensors, 4...Control unit, 5...
- Igniter, 6... Ignition coil, 7... Injector, 42... Microcomputer.

Claims (1)

[Claims] A rotation speed detection means and a load detection means for detecting the rotation speed and load of the internal combustion engine, an acceleration detection means for detecting the acceleration of the engine, and a load correction means for correcting the value of the load according to the acceleration. , comprising ignition timing calculation means for calculating the ignition timing of the engine according to the corrected load and the rotation speed, and ignition means for igniting the engine based on a signal indicating the ignition timing. Ignition timing control device.