JPS62182453A - Interruption increased fuel quantity controller in acceleration for electronically controlled fuel injection type internal combustion engine - Google Patents

Abstract

PURPOSE:To permit the interruption injection in good timing by comparing the actual engine acceleration in succession from the smaller value side out of a plurality of prescribed judgement levels and setting the interruption increased fuel quantity on the basis of the result of the judgement and carrying out the interruption injection. CONSTITUTION:A fuel injection quantity setting means B sets the fuel injection quantity on the basis of the operation state of an engine H which is detected by an engine operation state detecting means A, and the corresponding pulse signals are outputted into a fuel injection valve D from a driving pulse output means C. Further, in an acceleration state judging means E, the actual engine acceleration speed is compared in succession from the smaller value side out of a plurality of prescribed judgement levels, and an interruption increased fuel quantity setting means F sets the increased fuel quantity on the basis of the result of the judgement, and the corresponding interruption driving pulse signals are interrupted between the driving plus signals from an output means G, and said pulse signals are outputted into the fuel injection valve D. Thus, the interruption increased fuel quantity in acceleration is made proper, and the interruption injection can be carried out in good timing, and the acceleration responsiveness can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an interrupt increase control device during acceleration of an electronically controlled fuel injection type internal combustion engine.

<Prior Art> Conventional examples of electronically controlled fuel injection type internal combustion engines include the following.

That is, the basic injection amount Tp (=Kx
Q/N; is a constant), and after calculating various correction coefficients C0EF according to engine operating conditions such as cooling water temperature, air-fuel ratio feedback correction coefficient α, and correction coefficient Ts according to puffer battery voltage, fuel injection is performed. Quantity Ti (=TpXC
OEFxα+Ts) is calculated. For example, in a single point injection system (SP1 method), a drive pulse signal having a pulse width corresponding to the fuel injection iTi is output to the fuel injection valve in response to the engine's 172-rpm ignition signal, etc. Supply fuel to the engine.

By the way, some of the various correction coefficients C0EF include correction coefficients for acceleration increase, but pulse (fuel injection amount T
Since the response is poor during acceleration between pulses corresponding to i), so-called interrupt injection is performed to improve the response.

Immediately, during acceleration operation, for example, the rate of change (ΔQ) of the intake air flow rate Q is set to a predetermined value (ΔQ) as shown in FIGS.
x) is a slice level, and when this slice level (predetermined engine acceleration) is exceeded, an interrupt pulse signal of a predetermined value is inserted between the drive pulse signals, and an increased amount of fuel is injected at the beginning of acceleration. The aim was to increase the amount of fuel and improve acceleration response.

<Problems to be Solved by the Invention> By the way, in the conventional cut-in fuel increase during acceleration, even though a large amount of fuel is required to be increased when the engine suddenly accelerates (see Figure 9), Depending on the set value of the interrupt pulse signal, the required interrupt increase fuel amount may not be obtained during sudden acceleration, or the interrupt increase fuel amount may be too large during slow acceleration, causing the air-fuel ratio to become rich. It was not possible to sufficiently improve acceleration response.

Furthermore, since the output timing of the interrupt pulse signal exceeds a predetermined slice level (ΔQx), as shown in FIG. changes too quickly and the air-fuel ratio becomes over-lean. This is determined to be an acceleration based on the rate of change in the intake airflow iQ (or the rate of change in the throttle valve opening) detected by an air flow meter, etc., and interrupt injection is performed based on this acceleration determination, but the interrupt tamping is too early and the intake The air-fuel ratio becomes over-lean due to effects such as not supplying fuel to the cylinder where the air flow rate Q has increased. This overleaning of the air-fuel ratio may cause a misfire as shown in the change in indicated mean effective pressure shown in FIG.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide an acceleration increase control device that can obtain a required interrupt increase during acceleration by interrupt injection in a timely manner depending on the acceleration state.

Means for Solving the Problems> Therefore, in the present invention, as shown in FIG. a fuel injection amount setting means for setting a fuel injection amount based on the fuel injection amount; a drive pulse output means for outputting a drive pulse signal corresponding to the set fuel injection amount to the fuel injection valve; and a drive pulse output means for outputting a drive pulse signal corresponding to the set fuel injection amount to the fuel injection valve; an acceleration state determining means for sequentially comparing from the smaller side; an interrupt increase fuel amount setting means for setting an interrupt increase fuel amount based on the determination result of the acceleration state determination means; and an interrupt increase fuel amount setting means that corresponds to the set interrupt increase fuel amount. an interrupt drive pulse output means for inserting an interrupt drive pulse signal between the drive pulse signals and outputting the interrupt drive pulse signal to the fuel injection valve, an interrupt increase control device during acceleration of an electronically controlled fuel injection type internal combustion engine is configured. .

According to this configuration, the engine acceleration state is compared sequentially from the smallest of the plurality of determination levels, and based on the determination result, the interrupt increase fuel amount is set and the interrupt injection is performed, so that the engine accelerates slowly in the rapid acceleration state. Interrupt injection is performed more times than in the current state. For this reason, while performing interrupt injection at the appropriate timing during slow acceleration, during sudden acceleration, the interrupt injection is performed at the above-mentioned timing, and then a further increased amount of interrupt injection is performed, and the interrupt injection amount during acceleration is increased at the required timing during sudden acceleration. can be set.

Furthermore, during sudden acceleration, interrupt injection is performed more times than during slow acceleration, which allows the requested interrupt increase fuel amount to be dispersed and injected into interrupt pulses that gradually increase according to the actual intake air flow rate. The required interrupt increase fuel amount can be satisfied without making the air-fuel ratio over lean.

<Example> Embodiments of the present invention will be described below based on the drawings.

FIG. 2 is a block diagram showing an embodiment of an acceleration increase control device according to the present invention.

In this figure, the engine rotational speed signal N is the output of the rotational speed sensor l, the engine intake air flow rate signal Q is the output of the airflow meter 2, and the cooling water temperature is the output of the water temperature sensor 3 that detects the engine cooling water temperature. The signal TW is input to a control unit 4 containing a microcomputer constituted by an input/output device, a storage device, and a central processing unit, and the control unit 4 generates an injection pulse signal that is set as described below based on these signals. is output to the drive circuit 6 of the fuel injection valve 5. That is, in this embodiment, the engine operating state detection means is the rotational speed sensor 1. The air flow meter 2 and the water temperature sensor 3 correspond to this, and the control unit 4 also serves as fuel injection amount setting means, drive pulse output means, acceleration state determination means 1 interrupt increase fuel amount setting means, and interrupt drive pulse output means.

Next, the operation will be explained according to the flowcharts of FIGS. 3 and 4.

First, the fuel injection amount control routine will be explained based on the flowchart of FIG. 3. At Sl, the engine rotational speed N and the intake air flow rate Q detected by the rotational speed sensor 1 and the air flow meter 2 are read. And in S2,
From these values, the basic pulse Tp corresponding to the basic injection amount is determined.
(=KXQ/N, where ' is a constant) is calculated in the central processing unit.

In S3, data is stored in the storage device based on various operating conditions such as the water temperature Tw detected by the water temperature sensor 3 and the engine acceleration state.
A fuel injection pulse Ti is set by correcting the basic pulse Tp using various correction coefficients C0EF obtained by searching for correction coefficients based on each operating state to be set and calculating these correction coefficients in a central processing unit. Above 81~S
3 corresponds to fuel injection amount setting means.

The fuel injection pulse Ti set in S3 is applied to the drive circuit 6 of the fuel injection valve 5 at 84 as a drive pulse output means.
is output to.

In this way, when the engine is accelerating, the basic pulse is corrected to increase using various correction coefficients C0EF in order to improve the acceleration performance, but the responsiveness deteriorates when accelerating between the fuel injection pulses Ti. Interrupt injection is performed to improve responsiveness.

This interrupt injection control routine will be explained based on the flowchart of FIG.

In S5, the intake air flow i1Q and the water temperature 7'w detected by the air flow meter 2 and the water temperature sensor 3 are read. In S6, the intake air flow rate is calculated based on the intake air flow rate Q read in S5 and the intake air flow rate Q read last time. Q
The rate of change ΔQ (engine acceleration) is calculated.

In S7, the first determination level Δ for determining the acceleration of the engine is determined.
Compare Ql and ΔQ obtained in step 36, and if ΔQ≧ΔQl, proceed to the next step 38, perform interrupt injection, and determine ΔQ<Δ
Q! If so, return is performed without interrupting injection. Here, the first determination level ΔQl is different from the second and third determination levels ΔQ2, which will be described later, as shown in FIG. Δ
Q3 has a relationship of ΔQl<ΔQ2<ΔQ3, and the comparisons are made in order from the lowest determination level.

In S8, an interrupt injection pulse (interrupt drive pulse) Tp
Compute and output inj. That is, as shown in FIG. 5, the interrupt injection pulse Tpinjs is set corresponding to the first determination level ΔQl, and the water temperature correction is set as shown in FIG. 6, corresponding to the water temperature TW read in S5. Coefficient K
tw is multiplied to obtain an interrupt rJR injection pulse T p inj, and this interrupt injection pulse T p inj is inserted between the fuel injection pulses Ti to inject the interrupt increased amount of fuel.

Each judgment level ΔQ1. ΔQ2. The interrupt injection pulse T p inj set corresponding to ΔQ3 is similar to the magnitude relationship of the determination levels. That is, the rate of change Δ
The larger Q is, the larger the interrupt injection pulse width is (T p inj l< T p in
j 2〈Tl')inj3). In addition, the water temperature correction coefficient Kt
w is set in inverse proportion to the water temperature TW, and the lower the water temperature TW, the larger the interrupt injection pulse rlTpinj.

In S9, as in S7, the second determination levels ΔQ2 and ΔQ
If ΔQ≧ΔQ2, interrupt injection pulse Tpinj2 and water temperature correction coefficient Kti are determined in S10.
An interrupt injection pulse T p inj is calculated and output based on y.

Sll compares the third determination level ΔQ3 with ΔQ, and if ΔQ≧ΔQ3, in 312, an interrupt injection pulse T p inj is calculated and outputted using the interrupt injection pulse Tpinj3 and the water temperature correction coefficient Ktw.

Further, each judgment level ΔQ2. ΔQ
If it is determined that ΔQ does not exceed 3 (ΔQ<ΔQ2 or ΔQ3), the process returns in the same way as in S7.

As described above, the acceleration state determination means in this embodiment is S
7. S9. Sll corresponds to this, and the interrupt increase setting means and interrupt drive pulse output means are 38°510, S12
corresponds to

In this way, the rate of change ΔQ of the intake air flow rate Q determined in S6 is determined at each determination level ΔQ1. Interrupt injection is performed every time ΔQ2°ΔQ3 is exceeded, and the injection amount is increased each time.

Therefore, as shown in FIG. 7, during sudden acceleration when the rate of change ΔQ exceeds the third judgment level 603, three interrupt injections are performed as a result (shown by the solid line in the figure), and the rate of change ΔQ is at the second level. During slow acceleration that does not exceed the determination level ΔQ2, interrupt injection is performed only once (indicated by a dotted line in the figure).

Therefore, the interrupt injection pulse T is output in several parts.
When p inj is summed, it corresponds to a larger interrupt injection pulse being output during sudden acceleration than during slow acceleration, and the required value of the interrupt pulse (shown by the dotted line) shown in Fig. 9, that is, the required interrupt increased fuel amount. The acceleration response in each acceleration state can be improved. Note that if more determination levels are provided than in this embodiment, the required value can be further approached.

In addition, the interrupt injection pulse T p required during sudden acceleration
inj is output in several parts, and the number of pulses is gradually increased, so that an interrupt during a large pulse is generated approximately in synchronization with the increase in the intake air flow rate o.
Since nj is output at a good timing and the fuel is increased by the interrupt, the conventional interrupt injection timing (indicated by the dotted line) shown in Fig. 10 is brought closer to the required timing, and the air-fuel ratio The risk of becoming over-lean can be avoided.

In other words, the interrupt injection timing, which was too fast during sudden acceleration,
Each judgment level ΔQ1. ΔQ2. By performing an interrupt injection every time ΔQ3 is exceeded, the intake air flow f
Interrupt injection is performed when f1Q increases to prevent misfires due to overleaning.

In this embodiment, three determination levels ΔQ+,
ΔQ2. Although ΔQ3 is set, the number is not limited to this embodiment. Further, the acceleration state of the engine may be determined based on the rate of change of the basic pulse Tp (ΔTp) or the rate of change in the opening degree of the throttle valve (Δα) in addition to ΔQ.

<Effects of the Invention> As explained above, according to the present invention, the actual engine acceleration is compared sequentially from the smallest of a plurality of predetermined determination levels,
By setting the interrupt increase fuel amount based on the determination result and performing the interrupt injection, the interrupt increase fuel amount during acceleration due to the interrupt injection can be set to an appropriate amount, and the interrupt injection can be performed with good timing.

Therefore, it is possible to prevent the air-fuel ratio from becoming overlean due to the timing of the interrupt injection being too fast, particularly during sudden acceleration when the rate of change in the intake air flow rate is rapid, thereby preventing a misfire from occurring. Further, since the increase in the amount of interruption during acceleration due to the interruption injection during sudden acceleration can be increased, there is an effect that the acceleration response in each acceleration state can be improved.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of the present invention, FIG. 2 is a configuration block diagram showing an embodiment of the present invention, FIGS. 3 and 4 are flowcharts showing control in the above embodiment, and FIG. 5 is the same embodiment. FIG. 6 is a graph showing the relationship between the water temperature and the water temperature correction coefficient in the above embodiment, and FIG. 7 is a time chart showing the control characteristics in the above embodiment. , Fig. 8 is a time chart showing the conventional control characteristics, Fig. 9 is a graph showing the relationship between the rate of change in intake air flow rate and the interrupt injection pulse width in the above conventional method, and Fig. 10 is a graph showing the change in intake air flow rate in the above conventional method. It is a graph which shows the relationship between a rate and interrupt injection timing. 1...Rotational speed sensor 2...Air flow meter 3...Water temperature sensor 4...Control unit 5...Fuel injection valve 6...Drive circuit patent applicant
Japan Electronics Co., Ltd. Agent, Patent Attorney Fujio Sasashima CCC Finance link °゛shima夛-1-〉 -Oka 1 “j Koko IL Miguchi Self-reflection・↑Pulse 4 Jealousy Tpinj Procedure Amendment (
Self-restraint February 27, 1988 Commissioner of the Japan Patent Office Black 1) Akio Tono1, Indication of the case 1985 Patent Application No. 2932653, Person making the amendment Relationship to the case Patent applicant address Kasu, Isesaki City, Gunma Prefecture 1671 Youmachi 1 name
Japan Electronics Co., Ltd. Representative: Shigemi Sugino 4, Agent address: Daisan Mori Building, 1-4-1o Nishishin Ja, Minato-ku, Tokyo Column 6 for detailed explanation of the invention, Contents of amendment (1) Page 2 of the specification In the 13th line, change the word “correction coefficient” to “
Corrected as "Correction bone". (2) On page 4, line 14 of the specification, the phrase "not supplied" is amended to read "not supplied." (3) In the 1st line of page 7 of the specification, ``acceleration increase control device'' is corrected to ``interrupt increase control device during acceleration.'' (4) In the 18th line of page 7 of the specification, ``Drive pulse output The phrase "also serves as means for outputting driving pulses" is corrected to "also serves as means for outputting driving pulses." (5) In the 11th page, line 14 of the specification, the phrase "interruption increase" is corrected to "interruption increase fuel amount." (6) In the 4th line of page 13 of the specification, the phrase “Too early” has been replaced with “
"It's too fast," he corrected. (7) In the second line of page 14 of the specification, the phrase "so as to inject" is corrected to "so as to be injected." (8) In the 14th line of the specification, lines 11 and 12, the phrase "improvement" is corrected to "improve."that's all

Claims (1)

[Claims] an engine operating state detection means for detecting an engine operating state including at least an acceleration operating state; a fuel injection amount setting means for setting a fuel injection amount based on the detected engine operating state;
a drive pulse output means for outputting a drive pulse signal corresponding to a set fuel injection amount to the fuel injection valve; an acceleration state determination means for sequentially comparing the actual engine acceleration among a plurality of predetermined determination levels starting from the smallest one; an interrupt increase fuel amount setting means for setting an interrupt increase fuel amount based on a determination result of the acceleration state determination means; and an interrupt drive pulse signal corresponding to the set interrupt increase fuel amount inserted between the drive pulse signals. 1. An interrupt amount increase control device during acceleration of an electronically controlled fuel injection type internal combustion engine, characterized in that the interrupt drive pulse output means outputs the interrupt drive pulse to the fuel injection valve.