JPS5963330A - Method of controlling electrically controlled internal- combustion engine - Google Patents

Abstract

PURPOSE:To prevent surging by controlling fuel injection quantity and ignition timing on the basis of a leveled value of suction air quantity per one rotation of an engine. CONSTITUTION:If suction air quantity per one revolution of an engine is give to QNT, levelling controlling is carried out by tQNT (tQNT+tQNTSXtK)/(tK+ 1) in step 107. K is a leveled quantity. Then, fuel injection time, for example, is given by using the value of QNT which is quantity of suction air per one revolution of the engine after the levelling control operation. Thus, even if there occurs periodically fluctuation due to external factors, torque fluctuation in the engine may be prevented, thereby avoiding occurrence of surging.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control method for an electronically controlled internal combustion engine, and in particular to a method for controlling an electronically controlled internal combustion engine. The present invention relates to an improvement in a control method for an electronically controlled internal combustion engine that controls the fuel injection amount, ignition timing, etc. of the engine based on the engine load detected from the intake air amount.

In recent years, with the development of electronic technology, especially digital control technology,
Various sensors such as a rotation angle sensor, an intake air amount sensor, and a water temperature sensor are installed in each part of an internal combustion engine such as an automobile engine to detect the state of the engine. This is a so-called electronically controlled engine that controls the amount of fuel injected into the combustion chamber of the engine, ignition timing, idle rotation speed, etc. according to engine status signals such as engine speed, intake air amount, and engine cooling water temperature. It has been put into practical use.

In such an electronically controlled engine, especially the engine load,
In an electronically controlled engine that detects the intake air amount per engine revolution, the so-called intake air RPfa detection type detects the intake air amount Q per engine revolution. The fuel injection amount, ignition timing, etc. of the engine are controlled based on the engine load, and the engine can be accurately controlled according to the engine condition.

However, conventionally, when there is a resonance in which the intake air amount Q or the engine speed N changes periodically, the engine torque fluctuates due to the fluctuations such that the intake air amount & of one revolution of the engine fluctuates at a cycle. However, it has the disadvantage that it may cause so-called surging, in which vibrations from the front and rear of the vehicle diverge.

The present invention has been made to solve the above-mentioned conventional drawbacks, and can prevent surging regardless of periodic fluctuations in intake air iQ or engine rotational speed N, and therefore improves vehicle driving performance. An object of the present invention is to provide a method for controlling an electronically controlled internal combustion engine.

"Failure to fire" refers to the control method for an electronically controlled internal combustion engine in which the fuel injection amount, ignition timing, etc. of the engine are controlled based on the engine load detected from the intake air amount per engine revolution. The above objective is achieved by controlling the fuel injection amount, ignition timing, etc. based on the value of the intake air amount per engine revolution, thereby preventing surging caused by engine torque fluctuations. It is something.

In addition, the amount of intake air per revolution of the engine is set to different values during acceleration and deceleration, so that appropriate smoothing can be performed during deceleration without impairing responsiveness during acceleration. It is something.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of an intake air amount sensing type electronic control device for an automobile engine, in which a control method for an electronically controlled internal combustion engine according to the present invention is adopted, will be described in detail with reference to the drawings.

In this embodiment, as shown in FIG. 14, an intake sensor 16 built into the air flow make 14 for detecting the temperature of intake air, and an intake sensor 16 disposed in the throttle body 18 in conjunction with an accelerator pedal 20 disposed in the driver's seat. A throttle valve 22 that is opened and closed to control the flow rate of intake air, a throttle sensor 24 that includes an idle switch that detects whether or not the throttle valve 22 is at an idle opening, and an intake interference a surge tank 28 for preventing the above-mentioned throttle valve 22; and an idle rotation speed control valve (referred to as ISCV) 32 for controlling the idle rotation speed by controlling the opening area of a bypass air passage 30 that bypasses the throttle valve 22. , an injector 3 for injecting fuel toward each intake boat of the engine 10, which is arranged for each cylinder of the intake manifold 34.
6, a spark plug 38 for igniting the air-fuel mixture introduced into the engine combustion chamber 10a, and an exhaust manifold 40, which detect the rich-lean state of the air-fuel ratio from the oxygen concentration in the exhaust gas. The oxygen concentration sensor (referred to as the 02 sensor) 42 for the
a distributor 46 that does not have a distributor shaft 46a that rotates in conjunction with the rotation of the crankshaft of the engine 10, and distributes the distribution to the engine 8;
a crank angle sensor 48 built in the engine 10.6 that outputs a crank angle signal in accordance with the rotation of the distributor shaft 46a; A water temperature sensor 50 for detecting engine cooling water temperature, a battery 52, and the crank angle sensor 48, which are disposed in the cylinder block 10b.
The engine rotational speed N determined from the output crank angle signal and the intake air amount Q of the air flow meter 4 output are divided by the engine rotational speed N. The basic jet amount per stroke is determined, and this is calculated based on the output of the throttle sensor 24, the air-fuel ratio of the 02 sensor 42 output, the engine cooling water flow of the front water temperature sensor 50 output, the voltage of the battery 52, etc. By making the correction, fuel injection 1t is determined and a valve opening time signal is output to the injector 36, and the ignition timing is determined according to the engine rotation and an ignition signal is output to the ignition coil 44. death,
Furthermore, depending on the engine operating state, the l
In the intake air amount sensing type electronic control device for the automobile engine 10, which includes an engine control device 54 for controlling the engine I
The fuel injection amount and ignition timing are controlled (rC) based on the value obtained by smoothing the rotational intake air amount N using different smoothing amounts during acceleration and deceleration.

As shown in detail in FIG. 2, the engine control device 54 includes a central processing unit (referred to as CPU) 60 consisting of, for example, a microprocessor for performing various calculation processes, the air flow meter 4, an intake air temperature sensor 6. An analog-to-digital converter (A/D converter and 62, the idle switch of the front engine throttle sensor 24, the crank angle sensor 48, etc.
IS CV 32. , an input/output capotro 4 with a buffer function for outputting a control signal to the injector 36, ignition coil 44, etc., and a read-only memory (R) for storing control blocks and various data.
011,i) 66, a random access memory (referred to as RA R=1) 66 for temporarily storing calculation data, etc. in the CPU 60, and a backup memory that can be supplied with power from the auxiliary power source and retain memory even when the engine is stopped. It is composed of a random access memory 70 and a common bus 74 that connects each of the component devices.

The action will be explained below.

According to the present invention G', the intake sacred air amount q during one engine rotation is eliminated according to a routine as shown in FIG. That is, in step 101, the intake air amount Q output from the air flow meter 4 is determined by the crank angle sensor 4.
The latest value QN of the intake air amount per engine rotation, which is obtained by creating the engine rotational speed N obtained from the power of Yata and is stored in the RAM 68, is stored in the RAM.
68 and put it in register tQN. Next, the process proceeds to step 102, where the value QNT of the intake air amount for one rotation of the en-ref after the smoothing control calculation, which is stored in the RAM 68, is read out from the RAM 68, and is set to 1/the register tQNT. put in.

Next, the process proceeds to step 103, where the value QN of the intake air amount per engine revolution is determined by the engine 1 after the smoothing control calculation.
It is determined whether or not the amount of intake air at the rotational speed is greater than or equal to the value QNT. If the determination result is positive, that is, if it is determined that the intake air amount per engine revolution (engine load) is increasing during acceleration, the process proceeds to step 104, and the smoothing amount K A during acceleration is determined. Read CC from RAiVI68 and put it in the smoothing amount register tK. On the other hand, if the determination result in step 103 is negative, that is, if it is determined that the intake air amount per engine revolution (engine load) is decreasing and the engine is decelerating, then step 1
05, the amount of smoothing KDEC at the time of deceleration is read out from the RAM 68 and stored in the smoothing time register tK. The shift amount KACC during acceleration and the correction amount K D EC during deceleration are determined by the required amount of responsiveness of the intake air amount QN per engine revolution, but normally, The smoothing amount KACC during acceleration is the smoothing amount K during deceleration.
Assuming that D'zc is small, the specific gravity of the value QN before the smoothing control calculation with respect to the value QNT after the smoothing control calculation is set to be a dog during acceleration and small during deceleration, thereby impairing responsiveness during acceleration. This allows for effective smoothing control during deceleration.

After step 104 or 105, proceed to step 106, and use the following equation to determine the intake air volume per engine revolution between the value QN before the smoothing control and the value QNT after the smoothing control calculation.
Find the O difference and put it in the deviation amount register tQNTS.

tQNT S (-QN -QNT ・・・・・・・・・
...(1) Next, proceed to step 107, and calculate the deviation amount QNTS as shown in the following formula (by annealing the deviation amount QNTS, and calculating the f-axis annealed with acid, per engine revolution after the annealing 2 control calculation). Next, using the value QNT of the intake air amount per engine revolution after the smoothing control calculation, determine the fuel injection time τ according to the following formula, for example, or as shown in Fig. 4. , the ignition timing is determined using the advance angle map.

τ←A-B-QNT+τV ・・・・・・・・・・・・
・(3) Here, A is a constant, and B is the 02 sensor 4.
The correction coefficient τV, which is determined according to the air-fuel ratio of the two outputs, the engine cooling water temperature of the output of the water flow sensor 50, etc., is the invalid injection time of the injector 36.

In this way, even if changes in intake air iQ and engine rotation speed N cv are caused by external factors, engine rotation speed N and intake air amount per engine revolution 9
Changes in fuel injection time τ and ignition timing θ obtained from
The fuel injection time and ignition timing θ obtained from the value QNT of the intake air amount per engine revolution after the annealing control calculation are kept out of phase with each other in the actual calculation. , the actual air-fuel ratio deviates and the increase/decrease in engine torque is suppressed.

In this example, the value QN of the intake air amount per engine revolution before the smoothing control calculation (solid line) The value QNT of the intake air amount per engine revolution after the smoothing control calculation (broken line)
FIG. 5 shows an example of the relationship between the state of change in the air-fuel ratio and the difference between the base air-fuel ratio and the controlled air-fuel ratio.

During acceleration, indicated by arrow C in Fig. 5, the air-fuel ratio is on the one-in side; on the other hand, during deceleration, also indicated by arrow, the air-fuel ratio becomes rich, and the intake air amount per engine revolution changes periodically. It is clear that even if such fluctuations are caused by external factors, the actual air-fuel ratio shifts and the increase or decrease in engine torque is suppressed.

In the above embodiment, the fuel injection amount and ignition timing were controlled based on the values obtained by rounding down the intake air amount q per engine revolution, but the intake air amount q per engine revolution 9 For example, the same effect can be obtained by smoothing the engine rotational speed N before calculating the intake air amount H per engine revolution.

Further, in the above embodiment, the fuel injection amount and ignition timing are controlled based on the value obtained by rounding down the intake air iQ per engine revolution, but the control target is not limited to this. It is also possible to control other control objects, such as an idle rotation speed control valve.

As described above, according to the present invention, even if the amount of intake air per engine revolution fluctuates periodically due to external factors, the engine torque K does not change. Therefore, it has an excellent effect of preventing surging and the like and improving vehicle driving performance.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view including a partial block diagram showing the configuration of an embodiment of an intake air amount sensing type electronic control device for an automobile engine in which the control method for an electronically controlled internal combustion engine according to the present invention is adopted. Figure 2 is a block diagram showing the configuration of the engine control device used in the above embodiment, and Figure 3 is a block diagram showing the configuration of the engine control device used in the above embodiment.
Figure 4 is a flowchart showing the processing routine for smoothing the intake air amount per engine rotation. FIG. 5 is a diagram illustrating an example of an advance angle map for determining ignition timing based on speed, and shows changes in the intake air amount per engine revolution before and after the smoothing control calculation in the embodiment, and It is a diagram showing an example of the relationship between the difference between the base air-fuel ratio and the control air-fuel ratio. 10... Engine, 14... Air flow meter, 3
6- Injector, 38... Spark plug, 44...
・Ignition coil, 46...Taste distributor, 48・
...Crank angle sensor, 54...Engine control XI!
! ! i, Ft. Agent Takaya Ga.J (and 1 other person) Figure 3 Figure 4 NE

Claims (2)

[Claims] (1) In a control method for an electronically controlled internal combustion engine, the engine fuel injection amount, ignition timing, etc. are controlled based on the engine load detected from the intake air amount per engine revolution. Electronic control characterized by preventing surging caused by engine torque fluctuations by controlling fuel injection amount, ignition timing, etc. based on a value obtained by rounding down the intake air amount of the rotating engine. Method of controlling an internal combustion engine. (2) The control method for an electronically controlled internal combustion engine according to claim 1, wherein the smoothing amount of the intake air amount per engine revolution is set to different values during acceleration and deceleration.