JPH0458023A - Fuel injection control device for two-cycle engine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a fuel injection control device for a two-stroke engine, and particularly to a fuel injection control device for a two-stroke engine using an electronic fuel injection device. It is.

(Prior Art) In a two-cycle engine using a conventional electronic fuel injection device, there was no system for detecting the fully extended state of high engine rotation and high throttle opening and correcting the fuel injection amount.

(Problem to be solved by the invention) In a two-stroke engine, if the engine continues to be fully extended with high engine speed and high throttle opening, the temperature inside the exhaust pipe will rise, resulting in a lean air-fuel ratio and a high output. There was a problem that there wasn't one.

SUMMARY OF THE INVENTION An object of the present invention is to provide a fuel injection control device for a two-stroke engine that solves the above problems and makes it possible to obtain high output even in a fully extended state.

(Means and effects for solving the problem) In order to achieve the above-mentioned object, the present invention provides a fuel injection control device for a two-stroke engine using an electronic fuel injection device. a basic fuel injection amount setting means for setting a basic fuel injection amount based on the engine speed, a fully extended detection means for measuring the duration of the fully extended state of the engine based on the engine speed and the throttle opening, and a continuation of the fully extended state. The present invention is characterized in that it includes an increase correction means for gradually increasing the basic fuel injection amount according to time.

According to such a configuration, since the fuel injection amount increases when the engine is fully extended, the optimal air-fuel ratio can always be obtained, and high output can be obtained even when the engine is fully extended.

(Example) Hereinafter, an example in which the present invention is applied to a V-type engine will be described in detail with reference to the drawings.

FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention. In the figure, a V-type two-stroke engine E installed in a motorcycle has two cylinders, namely, the front cylinder (front bank, hereinafter referred to as F bank) IF and the rear cylinder (rear bank, hereinafter referred to as R bank) IR. It is growing.

In addition, in the same figure, a part of the F bank IF and the F bank IF are shown.
The intake passage, exhaust pipe, etc. that should be connected to the bank IF are omitted. In addition, this V-type two-stroke engine E,
The ignition timing of F bank IF and R bank IR is, for example, T.
It is set after the DC pulse output and after the crankshaft has rotated 90 degrees from the pulse output as a reference.

Exhaust ports 3A and 3B are opened on the inner surface of the cylinder 1 and are opened and closed by pistons 2A and 2B that are slidably disposed within the cylinder 1.
Control valves 4A and 4B are disposed above the exhaust port to control the timing of opening and closing of valve 3B. Further, the exhaust pipe 5 connected to the exhaust port 3A has a first pipe portion 5a whose downstream end is enlarged in diameter;
It consists of a truncated conical second pipe part 5b whose large diameter end is connected to the downstream end of the first pipe part 5a, and an expansion chamber 6 is provided in the downstream end of the first pipe part 5a and in the second pipe part 5b. provided.

A communication pipe 23 is fitted and fixed to the small diameter end, that is, the downstream end, of the second pipe portion 5b of the exhaust pipe 5, and the outer end of the communication pipe 23 is connected to the muffler 8. A truncated conical reflection tube 24 is disposed within the second pipe portion 5b as a control actuation means that reflects positive pressure waves generated by exhaust toward the exhaust port 3A. This reflection tube 24 is arranged in the second tube section 5b with its large diameter end facing the first tube section 5a, and a collar (not shown) fitted to the small diameter end of the reflection tube 24 communicates with the second tube section 5b. It is slidably fitted to the outer periphery of the tube 23.

The reflection tube 24 is equipped with a servo motor 26 as a drive source whose operation is controlled by the electronic control device 20 or a transmission mechanism 27.
connected via. That is, in the second pipe portion 5b,
A drive shaft 29 is mounted on the bearing section provided on the upper outer surface of the large diameter end.
is rotatably supported, and its drive shaft 29 and reflection tube 24
A driven shaft 30 installed at the large diameter end of the drive shaft 29 is connected by a connecting rod 31, and a transmission mechanism 27 is connected to the drive shaft 29.

According to this configuration, the connecting rod 31 swings as the drive shaft 29 is driven, thereby causing the reflection tube 24 to slide along the communication tube 23.

A potentiometer 34 is attached to the servo motor 26, and this potentiometer 34 detects the position of the reflection tube 24, that is, the amount of rotation of the drive shaft 290, and this detected amount θt is sent to the electronic control device 20 via the A/D converter 60. is man-powered.

In addition, the exhaust pipe (not shown) connected to exhaust port 3B
The reflection tube disposed inside may be driven by the servo motor 26 or another servo motor.

Control valves 4A and 4 provided in the exhaust ports 3A and 3B
B is a drive shaft 12A rotatably disposed on the cylinder 1;
, 12B. The drive shaft 12A is connected to a servo motor 14 as a drive source via a transmission mechanism 13 consisting of a booster, a transmission belt, and the like. The servo motor 14 also includes a potentiometer 15 for detecting the operating amount of the servo motor 14, that is, the opening degree of the control valve 4A.
This detected amount θr is also input to the electronic control device 20 via the A/D converter 60.

Note that the drive shaft 12B may be driven by the servo motor 14 or another servo motor.

An injector 52 is disposed on the downstream side of the throttle valve 58 of the two-stroke engine E in the air flow and in an intake passage connected to the R bank JR.

On the air flow downstream side of the throttle valve 58, the F bank I
The injector 52 is also located in the intake passage connected to F.
A similar injector is installed.

The injector 52 is arranged to inject fuel toward an engine oil (hereinafter simply referred to as oil) supply lower 7 that opens downstream of the throttle valve 58.

This injector 52 is connected to a fuel tank 56 via a fuel pump 54, and the fuel injection time (current supply time) thereof is controlled by the electronic control device 20.

Furthermore, lubricating oil is supplied to the oil supply lower 7 from an oil tank 75 by driving an oil pump 76 .

As a result of the injector 52 being arranged in this manner, the oil discharged from the oil supply lower 7 or the injected fuel can be washed away and efficiently supplied into the crankcase via the reed valve. .

The air-fuel mixture supplied into the crankcase is pre-pressurized by the descending piston and passes through the scavenging passage 96A.

96B into the combustion chamber.

A potentiometer 59 is attached to the throttle valve 58 to detect the opening degree θth of the throttle valve, and this detected amount θth is also input to the electronic control device 20 via the A/D converter 60.

A plurality of pawls 62 are formed on the crankshaft 61 of the two-stroke engine. This claw 62 is the first pulser P
It is detected by CI and second pulser PC2. Said first
The output signal of the second pulser PCIPC2 is inputted to the electronic control device 20.

Further, a shiatsu sensor 72 for detecting combustion chamber pressure (hereinafter referred to as shiatsu pressure) PI is installed at the head of the stud bolt 98, as will be described later in detail with reference to FIG.
2. Cooling water temperature sensor 73 that detects engine coolant temperature Tv, negative pressure sensor 74 that detects negative pressure PB, atmospheric pressure PA
An atmospheric pressure sensor 78 that detects atmospheric temperature Ta and an atmospheric temperature sensor 80 that detects atmospheric temperature Ta are also connected to the electronic control device 20 via the A/D converter 60. F bank I
A finger pressure sensor and a negative pressure sensor are also provided on the F side.

The electronic control device 20 includes a CPU, ROM, and RAM.

It is equipped with a microcomputer consisting of an input/output interface and a bus connecting them, and controls the energization timing and duration of the injector, as well as the ignition of the spark plug, the opening of the control valves 4A and 4B, and the reflection tube. control the position of

Note that numerals 57 and 79 are an air cleaner and a battery, respectively. Further, the arrow mark indicates the rotational direction of the crankshaft, and the arrows a and C indicate the inflow direction of the air-fuel mixture.

FIG. 3 is a block diagram of another embodiment of the present invention, in which the same reference numerals as in FIG. 1 represent the same or equivalent parts.

In this embodiment, the injector 51A1 for R bank IR
and the injector 51B for F bank IF, each scavenging passage 96A of R bank IR and F bank IF,
It is unique in that it is placed in a position where you can aim at the 96B's exhaust port.

FIG. 4 is a partially enlarged view of the R bank IR, and the same reference numerals as in FIG. 3 represent the same or equivalent parts. In addition, F
The bank IF also has the same structure.

In the same figure, the injector 51A is connected to the scavenging passage 9.6.
A is installed in such a direction that fuel is directly injected onto the back surface of the head of the piston 2A. Fuel injection is piston 2
The fuel is injected at the timing when the fuel is directly injected to the back surface of the head of the piston 2A through the hole 93 provided in the skirt portion of the piston 2A.

The injected and atomized fuel is first filled into the crankcase, and then filled into the combustion chamber via the scavenging passage 96A.

According to such a configuration, the fuel is well atomized, the combustion efficiency is improved, and the piston 2A is
is cooled, improving cooling performance. Moreover, since the atomized fuel is once filled into the crankcase, the fuel can act as a lubricant for the crank.

Further, the acupressure sensor 72 and the washer 95 are connected to the stud bolt 98, and the lead wire of the acupressure sensor 72 is connected to the stud bolt 98. 2a is supported by a claw 95a of a washer 95.

According to such a configuration, the acupressure sensor 72
The maintenance of the plug 71 can be performed more easily than when the plug 71 is installed in communication with the plug 71. Furthermore, since there is no need to remove the acupressure sensor when replacing the plug, it is possible to protect the sensor and maintain output accuracy.

FIG. 5(a) shows the injector 51. It is a figure showing another installation method of A, and the same code|symbol as the above represents the same or equivalent part. In addition, FIG. 9B is a plan view of the inside of the cylinder seen from the direction of arrow A shown in FIG. , the target position 97 is approximately at the center of the exhaust opening 94 of the exhaust port 3A.

In this embodiment, the injector 51A is installed at a position where it can aim at the exhaust port of the scavenging passage 96A, and in a direction such that fuel is directly injected into the target position 97. Fuel injection is
The fuel is injected at the timing when the fuel is directly injected into the head of the piston 28.

According to such a configuration, the fuel is atomized well and the fuel is injected upward, so that the combustion efficiency is improved.

Next, the operation of one embodiment of the present invention will be explained.

First, we will explain the Ne pulse and cylinder pulse (or TDC pulse, hereinafter referred to as C pulse) necessary for explaining the operation of one embodiment of the present invention.
The YL pulse) will be briefly explained.

FIG. 6 is a diagram for explaining the Ne pulse and the CYL pulse, and FIG. Figure (b) shows the crankshaft 61 in the same figure (
a) First and second balsa P when rotated in the direction of the arrow
2 is a timing chart of pulses output from CI and PC2, as well as Ne pulses and CYL pulses.

As is clear from FIG. 6, the Ne pulse and the CYL pulse are the OR signal and the HAND signal of the pulses output from the first and second balsers PCI and PC2.

Here, as shown in detail in Fig. 7, the first and second
Since there is a slight time lag between the pulses output from the balsa PCI and PC2, the Ne pulse, which is an OR signal, is output earlier than the CYL pulse, which is an AND signal.

Note that the stage counter is incremented every time a Ne pulse is output, and this count value is incremented every time a CYL pulse is output, or every time a predetermined number of Ne pulses are output after a CYL pulse is output. will be reset. That is, in this example, the number of stages (stage number) is 0 to 6.

Next, crank interrupt processing using the Ne pulse according to this embodiment will be explained.

FIG. 8 is a flowchart of the crank interrupt routine.

After the ignition switch is turned on, the engine status, that is, various engine parameters (atmospheric temperature Ta, cooling water temperature TV, atmospheric pressure Pas negative pressure PB, throttle opening θ)
th and battery voltage vb) are input and a series of initial processing is completed, a crank interrupt, TDC
Interrupt processing such as interrupts is permitted.

When a crank signal is detected after the interrupt is enabled, various starting controls are performed in step 510, and step Sll
Then, it is determined whether the stage determination has been completed or not. In step S12, IF stage discrimination is performed, and if the stage is "0" or "5", in step 513, the reciprocal number Me of the engine rotation speed Ne is calculated, and in step S14
Proceed to.

Further, if the stage is other than "0" or "5", the process directly advances to step S14.

However, when Ne is high, TDC is 3 depending on Ne.
60'720' 440° step S
14, otherwise the process ends.

In step S14, deterioration correction processing, acceleration reduction correction processing, and PI intake timing correction processing are performed as processing for adjusting the basic fuel injection amount Ti, and the basic fuel injection amount T1 is set.

The deterioration correction process, acceleration reduction correction process, and PI capture timing correction process will be described below.

(1) Deterioration correction processing Deterioration correction is based on the difference between the absolute value of the target negative pressure PB and the actual negative pressure PB during idling in order to cope with changes in the optimal fuel injection amount due to aging of the engine. , to adjust the amount of fuel injection.

For example, if the amount of intake air decreases due to engine deterioration over time, the air-fuel ratio will become richer. Also, if friction is reduced due to the running-in effect and output increases, the amount of intake air will increase compared to the initial stage, so the air-fuel ratio will become richer. becomes thinner.

Therefore, the target negative pressure PB and the actual negative pressure P under predetermined conditions
B is compared, and if the absolute value of the actual negative pressure PB is large, a reduction correction is performed, and if it is small, an increase correction is performed.

FIG. 10 is a flowchart of the deterioration correction process.

In step 5501, it is determined whether the engine is idling based on the engine speed Ne and the throttle opening θth, and if it is not idling, step 8508
Proceed to.

If the vehicle is idling, a deterioration correction coefficient KIJsO is calculated in step 5502.

A method of calculating the deterioration correction coefficient KLESO will be explained using FIG. 29. In FIG. 29, the horizontal axis shows the negative pressure PB, and the vertical axis shows the correction coefficient KLEso.

First, the ideal negative pressure PBref at the time of stable ignition according to the current engine speed Ne and throttle opening θth
Search from the data table. Next, a point KLESO""-0 is set for PB, and at the same time a predetermined value KLBTM is set for PB-0.

A straight line C passing through these two points is determined, and on this straight line C, a point on the KLESO axis (indicated by B in Fig. 29) corresponding to the current negative pressure PB (indicated by A in Fig. 29) is determined. calculated points) by linear interpolation. The value of this point B becomes the value of KLESO to be calculated.

In step 5503, it is determined whether the update determination timer that measures the period during which the coefficient KLESO calculated according to the current negative pressure PB is the same value, in other words, the period during which the negative pressure PB is the same value, is counting. If it is determined that counting is not in progress, KLESO is set to the coefficient KLEs1 in step 5509, and after starting a timer in step 5510, the process proceeds to step 5508.

On the other hand, if the timer is counting, step 5504
In step 5507, the coefficients KLESI and KLESO are compared, and if they do not match, the timer is stopped in step 5507, and then the process proceeds to step 850B.

Further, if the two match, it is determined that there is a possibility that deterioration has occurred, and the update determination timer is referred to in step 5505. In step 5505, it is determined whether a certain period of time has elapsed, in other words, whether the coefficient KLESO calculated in step 5502 is the same as the scheduled period. KLESI is set in KLEs to update the coefficient KLES, and the process proceeds to step 5508.

In step 550B, a coefficient KL is added to the basic fuel injection amount Ti.
This is multiplied by ES and registered as a new fuel injection amount TOllT.

According to such deterioration correction processing, the optimal fuel injection amount can always be obtained from the initial state of the engine, after it has been broken in, and even after it has deteriorated over time, so that the optimal air-fuel ratio can always be obtained.

(2) Acceleration reduction correction processing Acceleration reduction correction eliminates poor acceleration where the intake air amount does not increase in proportion to the throttle opening θth during acceleration, the air-fuel ratio becomes rich, and good acceleration is not performed. This is a correction to reduce the fuel injection amount, which temporarily reduces the fuel injection amount that is increased according to θth, so that the optimum air-fuel ratio is always maintained.

Hereinafter, the acceleration reduction correction will be explained in detail using FIGS. 11 to 15.

FIG. 11 is a flowchart of accelerated weight loss correction.

In step 5301, the engine speed Ne is 700.
It is determined that the rotation is 0 rotation or more, and further, step 5302
In step 5303, if it is determined that Ne is less than 10,000 rotations, the throttle opening degree θth
The amount of change Δθtb is taken in.

On the other hand, the rotation speed Ne is 7000 rotations or less or 1000 rotations
If the rotation is 0 or more, the process ends.

In step 5304, the amount of change in throttle opening Δθt
h is compared with a predetermined value G (for example, 5%/4 m s), and if Δθth≧G, it is determined that the vehicle is accelerating, and the process proceeds to step 5305, and if Δθth<G, the process proceeds to step 5311.

In step 5305, an acceleration correction flag XKAcc indicating whether or not acceleration correction is in progress is checked, and if acceleration correction is already in progress (XKAcc=1), the process jumps to step 8308.
Acceleration correction is not in progress (XKACC=0) and step 53
Proceed to 06.

In step 5306, an acceleration initial flag XTHcL indicating whether or not acceleration is in the initial stage is checked, and
L-1), the process proceeds to step 5307, and if it is not the initial stage of acceleration (XTIICL"0), the process ends.

Here, the setting process of the acceleration initial flag XTHCL, which is executed as pre-processing of the acceleration reduction correction, will be explained using the flowchart of FIG. 12.

In step 33061, the initial state of the flag XTHCL is determined and is XTHcL-1, and in step 530
When the throttle opening degree θth is determined to be, for example, 20% or more in step 62, the flag XTHCL is reset in step 53063.

On the other hand, it is XTHcL-0 and step 33064
If the throttle opening degree θth is determined to be 596 or less in step 83065, the flag XTl(CL
is set.

In addition, even if XTIICL"", the throttle opening θt
If h is less than 20%, or if the throttle opening θth exceeds 5% even if XTHCL'' is 0, the process ends as is.

The acceleration initial flag XTHC general determination result based on such throttle opening degree θth is as shown in FIG.

Returning to FIG. 11 again, in step 8308, KAcc
The acceleration reduction correction coefficient K is calculated based on the /θth table. As shown in FIG. 14, various KACC values are registered in the KAcc/θth table using the throttle opening θth as a parameter.

In this embodiment, the acceleration reduction correction coefficient KACC uses the throttle opening degree θth as a parameter, θth=10%, 2
Although four points, 0%, 30%, and 40%, are registered, if the actual θth does not correspond to each point, the optimum value is calculated by interpolation processing based on the four points. In addition, the coefficient K
ACC may be registered or calculated using engine speed Ne as a parameter.

In step 5309, Δ is set to 800 and a set value NKH is set to the correction hold counter based on the data table.
LD is searched.

NKHLD is a timer that measures the period during which it continues to determine that the acceleration is in the initial stage even after Δθth becomes less than a predetermined value (G), and ΔKACC is a timer that measures the period in which the fuel injection amount T is determined after the end of the period. This is a coefficient that is added to the coefficient KACC to gradually increase the LIT.

In this data table, as shown in FIG. 15(a), there are three types of values (N1, N2, .N3) and (ΔKl, 2 for Δ and 3 for Δ are available, and the optimum value is searched according to the rotational speed Ne.

In addition, in the above explanation, it was explained that 'KAce, ΔKACC, and NKHLD are calculated and searched separately, but if the data table shown in FIG. 15(b) is set, the step 5309 can be changed to can be integrated into.

In step 5310, a coefficient K is added to the fuel injection amount TOLIT.
The new fuel injection amount T is multiplied by Acc. V□ is set.

On the other hand, if it is determined in step 5304 that Δθth<G, then in step 5311 the acceleration correction flag XKACC is checked, and the flag
= 1), the process advances to step 5312, and if the correction is not in progress, the process jumps to step 5316.

In step 5312, the correction hold counter NXIJ
LD is checked, and if NXIILD is not 0, then in step 5313 NKIILD is decremented and then the process proceeds to step 5310.

If NKHLD=0, in step 5314, ΔKAcc is added to the acceleration reduction correction coefficient KACC to set a new acceleration reduction correction coefficient KACC.

In step 5315, the upper limit of the coefficient KACC is checked, and if KAcc<1, the process proceeds to step 5310;
If KACC≧1, in step 5316 KA
cc is set to 1.0, and in step 5317, the acceleration correction flag XKACC is reset, and the process ends.

According to such acceleration reduction correction, since fuel is temporarily reduced during acceleration, good acceleration performance can be obtained.

(3) PI take-in timing correction PI take-in timing correction is to correct the PI take-in timing according to the engine rotational speed Ne so that a misfire determination can be performed reliably.

First, a misfire determination method using acupressure PI will be briefly explained.

Figure 16 shows before TDC (BTDC) and after TDC (A
(a) shows the state at the time of ignition, and (b) shows the state at the time of misfire.

As is clear from the comparison of both figures, at the time of ignition, the shiatsu PI
shows a high value at a timing slightly delayed from TDC,
At the time of misfire, the acupressure PI only shows a peak value near TDC.

Therefore, in the conventional technology, the TDC is the center, and the four points before and after it are
Fixed shiatsu PI import timing within a 5° range 2
Set two positions (for example, -30° and +30°), and pre-TDC acupressure PI at the time of ignition at each timing. The difference ΔPIf between and the post-TDC acupressure PI rt is the pre-TDC acupressure PI at the time of misfire. Based on the fact that the difference ΔPI[Il between PIm1 and post-TDC finger pressure is sufficiently larger than Il, it was determined that ignition occurred if the difference between PIo and Pll exceeded a predetermined value, and misfire occurred if the difference between PIo and Pll exceeded a predetermined value.

However, especially in two-stroke engines, when the engine is in a high rotation range, the ignition timing is delayed to increase the temperature of the exhaust pipe in order to effectively utilize the exhaust pulsation effect and obtain high output. .

FIG. 17(a) shows the finger pressure at the time of ignition when the ignition timing is delayed at high Ne, and FIG. 17(b) shows the pressure at times of misfire.

As is clear from the figure, when the ignition timing is delayed when Ne is high, the finger pressure PI at the time of ignition shows two peak values at TDC and the subsequent ignition, and temporarily decreases during that time.

Therefore, even though the ignition timing is delayed, if the intake timing is fixed at 30 degrees as described above, the detected finger pressure difference ΔPIr becomes small, making it difficult to determine a misfire.

Therefore, in this embodiment, the PI intake timing is delayed (for example, by 45 degrees) according to the engine rotation speed Ne. In this way, the shiatsu pressure Pl before TDC at the time of ignition
p. The difference ΔPlp between and the post-TDC shiatsu PI, or the difference Δ between the pre-TDC shiatsu PI, o and the post-TDC shiatsu PI at the time of misfire.
Since it is sufficiently larger than PIM, misfire determination can be easily performed.

The misfire determination method based on the difference ΔPl between PIo and Pll in this embodiment will be described below with reference to FIG. 30.

In the figure, the misfire determination reference value DPI is set for each F bank and R bank based on the engine rotational speed Ne and the throttle opening degree 6th (each broken line).

The throttle opening degree θth has three reference values THI-.

THM, THH (THl, <THM <THH)
divided into multiple regions by THI, ≦θth<T
HM refers to the broken line LP (Ll?), and THM≦θt
In h<THt(, the broken line MR(MF> is referred to, and THI
(When ≦θth, the broken line HF (HR) is referred to.

If θth<THL, misfire determination is not performed.

The combustion state is determined by comparing the misfire determination reference value DPI, which is determined based on the engine speed Ne and the throttle opening θth, with the above ΔPI, and if DPI≦Δ
If PI, it is determined that there is an ignition, and if DPI>ΔPI, it is determined that there is a misfire.

Next, PJ capture timing correction will be explained in detail using the flowchart of FIG. 18.

In step 5400, it is determined whether or not priority processing exists, and if so, the processing is performed in step 5408.
If it does not exist, the process advances to step 5401.

The priority processing here refers to the flag XPIPIG, which will be described later.
ET 'XPIRQGET' RIGET
This is the process when either PIXPIFoGET is set.

Each flag described above represents the timing of the next Shiatsu PI to be detected. For example, if XPIFIGET is set, Shiatsu PIF1 after TDC (ATDC) of the F bank IF will be detected, and XP■ will be set. If so, Shiatsu P I RO in front of TDC (BTDC) of Nk IR
It means to detect.

In step 5401, stage determination is performed, and the following processing is executed depending on the stage number.

■Front bank negative pressure PBF at stage 0 2 step 5402
is read, and in step 5403, the flag
After setting PIGET, the process ends.

■ Stage discrimination, 2. 3: Finish the process.

■Stage-4; After setting the flag XPIROGET in step 5404, the process ends.

■Stage-5 = Rear bank negative pressure P B n at step 5405
is read, and in step 5406 the flag XPIR
1. After setting GE□, end the process.

■Stage 5 After setting the flag XPIFocET in step 5407, the process ends.

On the other hand, in steps 8408 to 5411, each of the flags XPIPIGET'XP'ROGET'XP
I 1X P I FOGET is determined.

RIGET Depending on the state of each flag, the counter NPI is set as a count value indicating the timing to take in the acupressure PI in step 5.
412 is TMPIFl, and step 5413 is TMP
IFo, in step 5414 T M P I R1,
In step 5415, TMPIRo is set.

It should be noted that each of the above count values is a value set in "PI correction coefficient processing" which will be explained later with reference to FIG. 22, and changes depending on the engine speed or the retardation of the ignition timing.

''--When a value corresponding to the state of each flag is set in the timer, the timer starts counting down in step 5416.

Hereinafter, timer interrupt processing, which is preferentially processed when the timer reaches "0", will be explained using FIG. 19.

The time when the timer reaches "0" indicates that it is the timing to capture the acupressure PI.

In steps 8421 to 5424, each of the above-mentioned hula ROGE
TXPI GXPI ・XPIRIGET 'FO
GET/XPI is determined, and the detected acupressure PI is determined according to the state of each flag in step 5425.
PIFo in step 5426.
In step 5427, it is captured as PIRl, and in step 5427, it is captured as PIR6.

That is, if the flag XPIRoGET is set, the acupressure P1 captured at that timing is the PI in the R bank, and if the flag XPIFIGET is set, the acupressure PI captured at the timing is the PI in the F bank. , is registered as .

In steps 8429 to 5432, each of the flags is reset.

In this way, according to the PI capture timing correction, the acupressure PI capture timing can be arbitrarily set by setting predetermined count values in the timers TMPI TMPIFo and TMPIRIIF1' TMP IRO.

Returning again to the crank interrupt processing in FIG. 8, step S
In step S15, stage discrimination is performed, and if the stage is other than "0", the process ends, and if the stage is "0", the process advances to step S16.

Hereinafter, using the flowchart of FIG. 9, step S1
The correction calculation process No. 6 will be explained.

In step 521, the negative pressure PB and the throttle opening θth are read, and in step S22, various correction processes for the fuel injection amount according to atmospheric pressure, atmospheric temperature, water temperature, etc., as well as misfire correction processing and PI correction processing are performed. , and image stabilization processing is executed.

(1) Misfire correction process The misfire correction process is a process of detecting the occurrence of a misfire and reducing the fuel injection amount.

FIG. 20 is a schematic flowchart of the misfire correction process, and the correction contents for the misfire correction consist of the following four types of correction.

■PB correction PB correction means that when a misfire is detected by the negative pressure PB detected by the negative pressure sensor 74, a PB correction coefficient (KPB; KPB≦1) is calculated and the fuel injection RT is performed.
is a correction ut which is multiplied by ut and reduces the fuel injection amount.

■PIPI Fl correction means that when a misfire is detected by the finger pressure PI detected by the finger pressure sensor 72, a PI correction coefficient (KPI "PI≦1) is calculated and the fuel injection ff1 is adjusted.
This is a correction that multiplies T and gradually increases the fuel injection amount.

■ Misfire ignition correction Misfire ignition correction is calculated by counting the number of transitions from the misfire state to the ignition state, and calculating the misfire ignition coefficient (KMF - KMF ≦ 1) when the number of transitions is greater than the number of transitions and the possibility of misfire is high. This is a correction in which the fuel injection amount T is multiplied and the injection amount is gradually increased by 0υ of fuel.

■ Full extension correction Full extension means that the throttle opening θth is very large.
(for example, 9096 or more) and the engine speed Ne is very high (for example, 12,000 rpm or more), which means a state in which the temperature inside the exhaust pipe increases. If such a state continues for a certain period of time, the exhaust temperature will increase. increases and the exhaust pulsation effect takes effect sufficiently, resulting in a lean air-fuel ratio. Therefore, if the fully extended state continues, it is necessary to increase the fuel injection amount to enrich the air-fuel ratio.

Therefore, in this embodiment, when the high Ne and high θth are maintained for a predetermined time or longer and the fully extended state is reached where misfires are unlikely to occur, the fully extended correction coefficient (KHIGH'K)
≧1) and calculate the fuel injection amount T. The fuel injection amount is gradually increased by multiplying by Ul.

Hereinafter, the outline of the correction process will be explained using the schematic flowchart of FIG. 20, and then its contents will be explained in detail using the flowchart of FIG. 21.

In step 5100 of FIG. 20, a misfire is determined based on the negative pressure PB detected by the negative pressure sensor, and when a misfire is determined, in step 5101, it is determined that the misfire state continues for a preset scheduled period. If it is not continued, in step 5102 the PB
A correction coefficient (KPB) is set, and in step 5103, the fuel injection amount TOUT is multiplied by the coefficient KPB to set the fuel injection amount "OUT".

If the above-mentioned misfire determination based on the negative pressure PB continues for the scheduled period, or if the ignition determination based on the negative pressure PB is performed, the process proceeds to step 5l (from step 11 to step 51).
04, a misfire determination is performed based on the finger pressure P1.

If a misfire is determined in step 5104, step 510
In step 5106, the PI correction coefficient (KP, ) is set, and in step 5106, the fuel injection ``TOUT'' is multiplied by the coefficient K to obtain a new fuel injection ff1T.

I is set.

Note that the PI correction coefficient KPI is updated so as to gradually decrease each time step 5105 is executed.

On the other hand, if ignition is determined in step 5104, step 5107
It is determined whether the determination result based on 00 is a misfire or an ignition.

If the previous misfire was determined, a misfire/ignition correction coefficient (KMF) is set in step 8108, and in step 5109, the fuel injection amount ToUT is multiplied by the coefficient KMF to obtain a new fuel injection amount T. LIT is set.

Note that the misfire/ignition correction coefficient KMP is updated so as to gradually decrease each time step 5108 is executed.

On the other hand, if it was determined in step 5107 that ignition occurred last time, or after it was determined that misfire occurred in step 5107, step 51
When 08.5109 is executed, the process goes to step 51.
The process advances to step 10, where a full extension determination is made.

If it is determined in step 5110 that it is in the fully extended state, it is determined in step 5111 whether or not the scheduled period has elapsed, and if it has elapsed, a fully extended correction coefficient (KHIGH) is set in step 5112, and At 5113, the fuel injection amount TOUT is multiplied by the coefficient KHIoH to set a new fuel injection amount TOUT.

Note that the full extension correction coefficient KHIGH is determined in step 511.
2 is updated to increase gradually each time it is executed.

Next, the misfire correction process will be explained in more detail using the flowchart shown in FIG.

The misfire correction process is executed, and first, in step 5201, it is determined that the engine rotation speed Ne is 6000 rotations or more, and further, in step 5202, it is determined that Ne is 14.
If it is determined that the rotation is less than 000 revolutions, step 520
In step 3, a misfire determination is made based on the negative pressure PB.

On the other hand, the number of revolutions Ne is less than 6000 revolutions or 1400 revolutions
If the rotation is 0 or more, the probability of misfire occurrence is very low, so there is no need for misfire correction. Therefore, the process sets the PB correction number counter NPB to 10, for example, in step 8226, and further sets the PB correction number counter NPB to 10 in step 5227.
Reset I correction number counter NPI, PI correction coefficient K
After setting P1, the process ends.

The misfire determination method based on the negative pressure PB in step 5203 is roughly as follows.

First, the negative pressure in the intake pipe in the ignition state (hereinafter referred to as target PB) is searched from a target PB map using engine speed Ne and throttle opening θth as parameters. This target PB map contains N
Various target PB values are set using e, θth, and atmospheric pressure PA as parameters.

When the target PB is searched, the actual negative pressure PB is taken in and the difference (ΔPB
) or exceeds a predetermined pressure (for example, 7.5 [mmHg1]), it is determined that a misfire has occurred.

In the misfire determination method described above, the target PB map has a three-dimensional structure using Ne, θth, and atmospheric pressure PA as parameters, so a large memory capacity is required for the target PB map.

Therefore, in order to avoid using the atmospheric pressure PA as a parameter, the following misfire determination method may be adopted.

That is, the target value (hereinafter referred to as TPB) of (atmospheric pressure PA - negative pressure PB) at the time of ignition is registered in advance with Ne and θth as parameters, and when determining a misfire, it is searched according to Ne and θth at that time. Compare the calculated TPB with the difference between the actually measured PA and PB (PA-PB),
Judgment is made as follows.

T - (PA - PB) = DPB; Ignition B T - (PA - PB) = DPB; Misfire B However, in actual application, taking into account fluctuations in negative pressure PB and errors in the detection sensor, etc. Predetermined threshold D
Set PB (for example, 7.5 mmHg) and judge as follows.

TPB-(PA-PB)≦0;Ignition T-(PA-PB)>TPB;Misfire B As a result of the above determination, if a misfire is determined in step 5203, step 5204 determines that PI correction is in progress. Solag X during P1 correction is checked, which indicates
If XPl=0, that is, PI correction is not in progress, step 52
The process advances to step 05, and if PI correction is in progress (XP, = 1), the process advances to step 5215.

In this process, as shown in step 5101 of FIG. 20, even if the misfire is not resolved by the PB correction, the PB correction is repeated for a scheduled period of time, so immediately after the start of the process, the process proceeds to step 5205.

In step 5205, the count value NPB of the PB correction number counter indicating the number of times PBM correction has been executed is checked, and if it is not NPB-0, the count value is decremented by "1" in step 5206, and if NPB is 0, the count value NPB is decremented by "1". ,
After the count value "10" is set in step 5213, the count value is decremented by "1" in step 8206.

In step 5207, the PB correction number counter NPB is checked again, and if the PB correction has been executed for a predetermined period and is NPB-0, the PB correction counter NPB is checked in step 5214.
After the correction flag XPI is set, step 521
Proceed to step 6.

In step 8208, a PB correction coefficient KPB, which is a coefficient for correcting the negative pressure PB, is searched. PB correction coefficient KPB
is fuel injection mT to thin the air-fuel ratio in the event of a misfire.
is a ut coefficient smaller than 1 that is multiplied by .DELTA.PB, and is searched using the .DELTA.PB as a parameter.

In step 5209, a value obtained by multiplying the fuel injection HT by the PB correction coefficient KPB is registered as a new fuel injection mT.

ut In step 5210, the PI correction number counter NP1 is reset, and the PI correction coefficient KPI is set to 1. Similarly, in step 5211, a previous misfire flag XMF, which will be described later, is set, and a full extension correction number counter N
IIIGII and fully extended state flag XIIIGI
+ is reset, and then the process ends.

On the other hand, if the PB correction is executed for a predetermined period of time and the PI correction flag XP1 is set in step 5214, the next process will proceed from step 5204 to step 521.
Proceed to step 5.

Similarly, when ignition is determined in step 5203, the process proceeds to step 5215 after the PI correction flag XP1 is reset in step 5212.

In step 5215, the PB correction number counter NPB is set to
For example, "10" is set. In step 5216, the throttle opening θth is checked, and whether the opening θth or
For example, if it is 5090 or more, proceed to step 5217;
If it is less than 50%, the process proceeds to step 5227.

In step 5217, a misfire determination is performed based on the shiatsu PI, and if it is determined that a misfire has occurred, in step 5218, the PI
The correction number counter NPI is incremented over and over again. In step 5219, it is determined whether the NPI exceeds a preset upper limit.

If the NPI does not exceed the upper limit value, the process proceeds to step 5225, where a coefficient KCPI setting process is performed.

KCPI is a coefficient set to gradually reduce the fuel injection amount during PI correction, and is
It decreases according to the value of PI.

In this embodiment, if N -1, then K. , 1-1.0, and when the NPI is 2" or more, it is calculated as NPI-1 K - (0,95).

NPI On the other hand, if it is determined in step 5219 that the NPI exceeds the upper limit, then in step 5220 the NP
An upper limit value (for example, 30) is set to I.

In step 5221, a PI correction coefficient KPI is detected based on the detected acupressure PI, and in step 5222, the value obtained by multiplying KPI by KcPl is registered as a new KPI.

In step 5223, the lower limit of KPI is checked, and if KP < (0,95), then (0,95)
or KPI. In addition, as the lower limit value, KP
The coefficient set to I does not necessarily have to be (0,95)'', but may be a well-rounded value in the vicinity.Also, it is the lowest value of KPl registered as a correction coefficient. It's okay.

In step 5224, before fuel injection Ja=T
The value multiplied by the PI correction coefficient KPI is registered as the new fuel injection amount T, and the process then proceeds to step 5211. In addition, the step 5217
If ignition is determined in step 5230, the process proceeds to step 5230.

In step 5230, the throttle opening θth is 50.
If it is determined in step 5231 that the engine rotational speed Ne is not less than 6500 rotations, the previous misfire flag XMF is checked in step 5232.

Further, if the throttle opening degree θth is less than 50% or the engine speed Ne is less than 6500 revolutions, the process proceeds to step 5244.

If X, F=-t is not determined in step 5232, that is, if the previous time was an ignition state, the process proceeds to step 5239, which will be described later, and the previous time is a misfire state (XMF-1).
Then, in step 5233, the previous misfire flag XM
F is reset.

In step 5234, a misfire/ignition number counter Nll counts the number of state changes from a misfire state to an ignition state.
1f is checked, and if it is not Nl, 1f-0, the process advances to step 8246, where N is checked. After f has been decremented, the process advances to step 5239.

Further, if N1.1r=0, in step 5235, Nmf is set to, for example, "20", and in step S23
At δ, the misfire ignition counter NMF is incremented.

That is, the state change from the misfire state to the ignition state occurs 20 times and the counter N is reached. Every time +r becomes 0, the misfire/ignition counter NMF is incremented.

In step 5237, it is determined whether the NMF exceeds a preset upper limit. If the upper limit is not exceeded, the process proceeds to step 5245, where a misfire ignition coefficient KMF is set.

The misfire ignition coefficient KM- is a coefficient set to gradually reduce the fuel injection amount when a state change from a misfire state to an ignition state frequently occurs, and the misfire ignition coefficient KM-
It decreases according to the value of MF. In this MF example, P is calculated as K-''(0,9).

If it is determined in step 5237 that NMF exceeds the upper limit value, then in step 8238 NMF is set to the upper limit value (MAX).

In step 5239, a lower limit check of KMF is performed, and if K<(0,9) MAX, i MAX (0,9) is set in KMF.

Note that the coefficient set in KMF as the lower limit value does not necessarily have to be (0,9)MAX, and may be a well-defined value in the vicinity thereof.

In step 5240, the value obtained by multiplying the fuel injection mT by the misfire ignition coefficient KM is registered as a new fuel injection amount T.

ut In step 5241, the throttle opening degree 6th is checked, and if it is determined here that the throttle opening degree θth is not 90% or more, or if it is determined in step 5242 that the engine rotation speed Ne is not 12000 rotations or more. , the process proceeds to step 5243.

In addition, the throttle opening θth is 90% or more, and the engine rotation speed Ne is the rotation speed at which the horsepower peaks (for example, 12
000 rotations) or more, it is determined that the fully extended state is reached, and the process proceeds to step 5247.

In step 5247, the fully extended state flag
H If the fully extended state is not continuing, step 5256
In step 5257, the extension timer TMHIGII is set to, for example, 5 seconds, and in step 5257, the flag XHIG
II is set.

The extended timer TMIIIGH counts down as time passes, regardless of the processing.

Further, if the fully extended state flag XHIGH is "" in step 5247, it is determined that the fully extended state is continuing, and in step 5248, the fully extended state timer T
MHIGH is checked.

Here, if 5 seconds have passed since the timer was set without being updated and TMHIGH=0, then in step 5249 flag XHIG)! is reset, and in step 5250, the end-of-extension correction counter N)IIGH is incremented, and the process proceeds to step 5251.

In step 5251, it is determined whether NllllCl+ does not exceed a preset limit value. If it does not, the process proceeds to step 5255, where the end-of-extension correction coefficient KHIC11 is set.

The full extension correction coefficient K)IIGH is a coefficient for gradually increasing the fuel injection amount when the full extension state continues, and increases according to the value of the full extension correction number counter N)LIGII.

In this embodiment, KMF=(1
, 1) is determined as NHIGH.

If it is determined in step 5251 that ``I (IGI) exceeds the upper limit value (MAX), step 5
At 252, an upper limit value (MAX) is set for NHIG)I.

In step 5253, an upper limit check of K)IIGH is performed, and if K>(1,1)MAX, Hl(
J MAX (1,1) is set to KHIIJI.

Note that the coefficient set to KHIGH as the upper limit value does not necessarily have to be (1, 1) MAX, and may be a well-defined value in the vicinity thereof.

In step 5254, the new fuel injection amount T is the value obtained by multiplying the fuel injection 11;LT by the full extension correction coefficient KIIIC11 described above. It is registered as ut.

In this embodiment, the fully extended state is detected based on the engine speed and the throttle opening, so that the fully extended state can be detected without providing a sensor such as an exhaust temperature sensor.

Furthermore, since the basic fuel injection amount is gradually increased in accordance with the duration of the fully extended state, it becomes possible to obtain the optimum air-fuel ratio even in the fully extended state.

(2) PI correction process The method for calculating the correction coefficient KPI will be explained below using FIG. 22.

In step S70, Ne
/Search the PIo capture timing, PI, and capture timing (d e g) from the PI capture timing map.

FIG. 24 is a Ne/PI intake timing map,
A straight line A on the left side of the figure shows the relationship between Ne and the PIo uptake timing, and a broken line B on the right side of the figure shows the relationship between Ne and the Pll uptake timing.

As is clear from the figure, in this embodiment, the straight line B slopes upward to the right, and as the engine speed Ne increases, the timing of taking in PI is set to shift backward (towards TDC).

That is, in order to be able to capture as large a Pll as possible according to the engine speed Ne, the PI capture timing is set at or near the peak value of P I t.

Note that in this embodiment, the straight line A also slopes upward to the right, and as the engine speed Ne increases, the PIo intake timing also shifts backwards for the following reasons.

That is, as shown in FIG. 26(a), P I n
The acquisition process for o is started at the timing of ■ of the PC signal, and the acquisition process for P I R1% P I pol P I pt is started at the timings of ■, ■, and ■, respectively.

When the PI import process is started, the processes explained in connection with FIG.
), the timer starts counting down, and when the count value reaches "0", the interrupt process described in connection with FIG. 19 is executed, and when the process proceeds to a predetermined step, the capture process is executed.

Shiatsu pressure difference ΔPI and (PI - P
In order to increase the difference between PIo and Io), as is clear from FIG. 17, the earlier the PIo capture timing is, the better; , since there are various calculation processing times and timer down-count times, the engine rotation speed N
When e becomes high, the PI capture timing (angle) inevitably shifts backward.

In addition, in order to eliminate such a deviation in the timing of PIRo capture, two timers for timing detection are provided as shown in FIG.
The acquisition process regarding pIRl, PIF starts at the timing of PC signal ■. , P.I.

Regarding, it is sufficient to start at the timings of ■, ■, and ■, respectively.

In this way, the PIo capture timing can be set to a fixed value.

When the P1 capture timing is retrieved as described above, the timing (deg) is converted into angle and time, and the front bank capture timings P1o and Pll are determined by the TMPI TMPIFl described in connection with steps 5412 and 5413 in FIG. 18, respectively. Similarly, the FO rear bank capture timings PIo and px are the TMP described for 5414.5415, respectively.
Registered as ITMP IR□RO'.

In step 371, the acupressure difference ΔPI, which is preset according to Ne and θth and serves as a reference value for misfire determination, is searched. In step S72, ΔPI and (PI −
P Io), and ΔPI≧(PI −PIo
), that is, if there is a misfire, the correction coefficient KPI is searched in step S73.

In misfire detection using finger pressure PI, since the amount of intake air at the time of misfire cannot be estimated, the correction coefficient KPI is calculated based on the intake air ratio at the time of misfire.

Figure 23 shows the intake ratio Lp at the time of ignition and the intake ratio M at the time of misfire. is reversed, and in the zone where a misfire occurs, the intake ratio L at the time of ignition
p exceeds the intake air ratio M at the time of misfire. Therefore, in this embodiment, L M/L p is adopted as the correction coefficient K.

PI Note that the PI correction is an auxiliary correction when the misfire cannot be resolved by the PB correction, so it is necessary to set KPI<KPB. Furthermore, in order to ensure ignition, it is necessary to satisfy KPI≧(LM/LF), so KPI must satisfy the following equation.

(L/L)≦KP1<KPB MP Therefore, in this example, so that the KPI satisfies the above formula,
Set the coefficient K that satisfies the following formula, and set K, X(L /L
) is taken as the correction coefficient KPI.

P (LM/LF')≦KL×(LM/LF) <KPB In step S74, a correction coefficient K − is added to the fuel injection amount TOUT.
Multiply by K X (LM/LF) and use this as the new PI
Shina fuel injection amount T. It is called UT.

In the above explanation, the correction coefficient KPI was calculated based on LM/LF, but as is clear from FIG. 23, the intake ratio L in the zone where misfire occurs
Since p is approximately 100%, the same effect as described above can be obtained even if P is calculated based only on the intake ratio and the correction coefficient K.

In addition, in the above-mentioned embodiment, the detection timing of the shiatsu PI was explained as being retarded according to the increase in engine speed, but the ignition timing is detected and the detection timing is retarded according to the retardation of the ignition timing. It may be made to have a corner.

(3) Engine brake correction processing Engine brake correction processing refers to engine brake (engine brake)
In order to resolve poor deceleration, where the intake air amount does not decrease in proportion to θth and the air-fuel ratio becomes thinner during deceleration due to This process increases the amount of fuel injected to improve the engine's engine effect.

The camera shake correction process will be explained below using the flowchart shown in FIG.

If it is determined in step S90 that θth is low and further determined as high Ne in step S91, in step S92,
The preset constant KCNST (>1) is the coefficient KM
Set to AP.

Furthermore, if θth is not low or Ne is not high, the coefficient KMAP is set to "1" in step S93.

In step S94, the fuel injection amount "0LIT" is multiplied by the correction coefficient KMAR, and this is registered as a new fuel injection amount TOUT.

According to the engine brake correction process, an appropriate amount of fuel is supplied even in a low θth engine brake state, so that the engine brake effect can be improved.

Returning to FIG. 9 again, in step S23 it is determined whether or not cranking is in progress. If cranking is in progress, step S24 uses the cooling water temperature Tν from the cranking table to determine the temperature during cranking (starting). The fuel injection amount TI is searched for in the state (up to about 2 revolutions of the crankshaft from completion to warm-up operation). In step S25, Ti retrieved in step S24 is stored in a predetermined register.

On the other hand, if it is determined in step S23 that cranking is not in progress, in step S26, the basic fuel injection amount Ti for warm-up or normal state is searched from a map using, for example, engine rotation speed Ne and throttle opening θth as parameters. be done.

In step S27, the fuel injection amount Ti retrieved in step 326 is stored in a predetermined register as in step S25, and the process proceeds to step 328.

In step 828, fuel injection "TOUT" is calculated,
The calculated value is output in step S29.

By the way, as explained with reference to FIGS. 2 and 3, since only one injector is provided in this embodiment, the fuel injection amount can be adjusted accurately both at low Ne and at high Ne. It is difficult to do so.

Therefore, in this embodiment, intermittent injection control is adopted for fuel injection.

FIG. 26 is a block diagram of the intermittent injection control device of this embodiment.

In the figure, N detected by the engine rotational speed (Ne) detection means 10 and the throttle opening degree (θth) detection means
e and θth are input to rear (R) bank basic injection amount setting means 12, correction coefficient setting means 13, and intermittent pattern setting means 14.

The R bank basic injection amount setting means 12 searches the R map based on the input Ne and θth to find the optimum fuel injection amount T I R for the rear cylinder, and sets the injection amount T I R to the rear cylinder.
R is output to the intermittent injection means 16R.

By the way, the following equation (1) holds true between the rear map and the front map.

F map - R map × K ... (1) M Therefore, if the R map is multiplied by the correction coefficient KNM to obtain the F map, the optimal fuel injection jiTiF for the front cylinder can be determined without setting the F map. become easily sought after.

Therefore, in this embodiment, the correction coefficient setting means 13
The optimum fuel injection amount Ti for the front cylinder is determined from the fuel injection amount TiR determined by the bank basic injection amount setting means 12.
A correction coefficient KNM is calculated to obtain the following, and the correction coefficient KNM is outputted to the F bank basic injection amount setting means 15.

The F bank basic injection amount setting means 15 calculates the injection amount TiF by multiplying the injection amount T1 by the correction coefficient KNM, and calculates the injection amount TiF.
i −1-i , is output to the intermittent injection means 16F.

The intermittent pattern setting means 14 sets an intermittent pattern using θth and Ne as parameters from the data table shown in FIG.
Output to R.

The intermittent injection means 16F and 16R each have an injection amount T ip % T when the intermittent pattern is “injection once every two times”.
The IR is approximately doubled and output is performed once every two times, and if it is an intermittent pattern or "injection once every four times", it is approximately quadrupled and output is performed once every four times.

According to such intermittent injection, the basic fuel injection amount is approximately n
Double the amount of fuel is injected once every n times, so a sufficient amount of fuel is injected even during high rotations and high loads, and the engine condition is controlled from idling to high rotations and high loads. The optimal amount of fuel can be injected using a single injector.

Moreover, the number of intermittent intervals n is set according to the engine speed and throttle opening, so even when there is a sudden acceleration due to a sudden opening of the throttle from idling, or a sudden deceleration due to a sudden opening of the throttle, the intermittent number n is set according to the throttle opening. Also, good acceleration and deceleration characteristics can be obtained.

In addition, in the above-described embodiment of intermittent injection, the basic fuel injection amount of the F bank is calculated by multiplying the basic fuel injection amount of the R bank by the correction coefficient, but on the contrary,
The basic fuel injection amount for the F bank may be detected from a map, and the basic fuel injection amount for the R bank may be calculated by multiplying the basic fuel injection amount for the F bank by a correction coefficient.

Furthermore, when the present invention is applied to a normal series engine instead of a V-type engine, the correction coefficient setting means 13, the F bank basic injection amount setting means 15, and the intermittent injection means 16F may be omitted.

Note that the intermittent pattern of intermittent injection is not limited to the one shown above, and may be an intermittent pattern in which intermittent injection is always performed over the entire operating range, as shown in FIG. .

According to such an intermittent pattern, since intermittent injection is performed over the entire operating range of the engine, various calculation processes such as fuel injection timing control and injection amount calculation need only be performed once every n times.

Therefore, various arithmetic processing times are shortened and the system has more leeway, and this effect is particularly noticeable when Ne is high, making system design easier.

FIG. 1 is a functional block diagram of the embodiment of the present invention described above, and the same reference numerals as above represent the same or equivalent parts.

In the figure, a throttle opening degree θth detection means 101 detects a throttle opening degree θth. Engine speed Ne
The detection means 102 detects the engine rotation speed Ne using the Ne pulse output from the Ne pulse generation means 100. Injection timing control a1 [103 sets the fuel injection timing using the Ne pulse. The basic fuel injection amount setting means 104 sets the basic fuel injection amount T1 based on the opening degree θth and the rotation speed Ne.

The acceleration initial determination means 107 detects a sudden opening of the throttle/slot from a low throttle opening based on θth and Δθtl+. The engine brake detection means 108 detects θth and N
Deceleration due to engine braking is detected based on e. The reduction correction means 112 adjusts the fuel injection amount T at an early stage of acceleration.
Output a reduction coefficient KACC that subtracts 1. The increase correction means 113 outputs an increase coefficient KMAP for increasing the fuel injection ff1Tl during deceleration.

The fully extended detection means 109 measures the fully extended state time of high Ne and high θth. The amount increase correction means 114 outputs an amount increase coefficient KHIGH that increases the fuel injection amount Ti in accordance with the fully extended state time.

The deterioration determining means 126 determines the deterioration state of the engine based on the opening degree θth and the rotation speed Ne.

The increase/decrease correction means 127 outputs a coefficient KLES for increasing/decreasing the fuel injection ff1Ti according to the deterioration state.

The intermittent injection control means 123 controls the opening degree θth and the rotation speed N.
Based on e, fuel is intermittently injected.

The PB detection timing output means 124 and the PI detection timing output means 125 output the negative pressure PB detection timing and the acupressure PI detection timing, respectively, based on the rotation speed Ne.

The PB sensor 115 detects the pressure inside the intake pipe.

PI sensor 116 detects the pressure within the combustion chamber.

The misfire determination reference output means 111 outputs a misfire determination reference value regarding the intake pipe pressure and the combustion chamber pressure based on the opening degree θth and the rotation speed Ne.

The first misfire determination means 117 determines the combustion state based on the detected value of the PB sensor 115 and the misfire determination reference value. The PB misfire count counter 118 counts the number of misfire determinations made by the first misfire determination means 117. The reduction correction means 120 outputs a reduction coefficient KPB that reduces the fuel injection ff1Ti when determining a misfire.

The second misfire determination means 119 detects either the ignition determination by the determination means 117 or the fact that the number of misfire determinations has reached a predetermined number, and compares the detected value of the PI sensor 116 with the misfire determination reference value. The combustion state is determined based on the

The PI misfire count counter 122 is the second misfire determination means 1.
19 is counted.

The reduction correction means 121 outputs a reduction coefficient KPI for subtracting the fuel injection amount Tj based on the count value of the PI misfire count counter 122.

The transition determining means 128 determines transition from a misfire state to an ignition state. The transition determination counter 130 counts the number of times the transition from the misfire state to the ignition state is determined. The reduction correction means 129 outputs a reduction coefficient KMP for subtracting the fuel injection ff1Ti based on the count value of the transition determination counter 130.

The fuel injection amount determining means 105 determines the fuel injection amount T by multiplying the basic fuel injection amount Ti by the reduction coefficient and increase coefficient. U
Determine l. The driving means 106 is configured to control the fuel injection "T".
Based on OUT, the energization time to the injector 51 (52) is controlled.

(Effects of the Invention) As is clear from the above description, according to the present invention, the fully extended state is detected based on the engine speed and throttle opening, so it is not necessary to provide a sensor such as an exhaust temperature sensor. It becomes possible to detect the fully extended state without any problems.

Further, since the basic fuel injection amount is gradually increased in accordance with the duration of the fully extended state, it becomes possible to obtain the optimum air-fuel ratio even in the fully extended state.

[Brief explanation of drawings]

Fig. 1 is a functional block diagram of the present invention, Fig. 2 is a block diagram showing the configuration of one embodiment of the invention, Fig. 3 is a block diagram of another embodiment of the invention, and Figs. 4 and 5 are rear bank diagrams. , Figures 6 and 7 are diagrams for explaining Ne pulses and CYL pulses, Figure 8 is a flowchart of crank interrupt by Ne pulse, Figure 9 is a flowchart of correction calculation, and Figure 10 is deterioration correction. 11 is a flowchart of the acceleration reduction correction, FIG. 12 is a flowchart of the acceleration initial flag XTHCL setting process, and FIG. 13 is a flowchart of the acceleration initial flag XTHCL setting process.
The figure is a timing chart of acceleration weight loss correction, FIG. 14 is a diagram showing the relationship between acceleration weight loss correction coefficient KACC and θth,
Figure 15 is a diagram showing the relationship between the correction coefficient and Ne, and Figure 16 is a diagram showing the relationship between the correction coefficient and Ne.
．． Figure 17 is a diagram showing the timing of importing acupressure PI,
Figure 18 is a flowchart for correcting PI capture timing, Figure 19 is a flowchart for timer interrupt, and Figure 20 is a flowchart for timer interrupt.
Figure 21 is a detailed flowchart of misfire correction, Figure 22 is a flowchart for calculating the correction coefficient KPI, Figure 23 is a diagram showing the intake ratio between ignition and misfire, and Figure 24 is a diagram showing the intake ratio between ignition and misfire. 25 is a flowchart of the engine brake correction process, FIG. 26 is a block diagram of the intermittent injection control device, and FIG. 27 is a diagram showing the intermittent pattern.
FIG. 28 is a diagram for explaining the timing of taking in the acupressure PI, FIG. 29 is a diagram for explaining the method for calculating the deterioration correction coefficient KLESO, and FIG. 30 is a diagram for explaining the misfire determination method using the acupressure PI. . l...Cylinder, 20...Electronic control device, 51A. 51B, 52... Injector, 61... Crankshaft, 72... Shiatsu sensor, 98... Stud bolt, 96A, 96B... Scavenging passage. Figure No. 5 Figure Δθ [h (%) Figure 16 (a)! ”-Himo (b) Kura Inu Bacteria Figure 17 (a) Uta Nezono 1 History 5 o’clock (b) γjNe’s Life in the North (8TDC) Ichiga TDC 5g (ATDC) (CrTDC) Ichigo DC 5v (AILX,;) Figure Engine rotation speed Ne (xi 03) rpm DC 45 (deg) (BTDC) (ATDC) Figure Figure

Claims (2)

[Claims] (1) In a fuel injection control device for a two-stroke engine using an electronic fuel injection device, there is a means for detecting the engine speed, a means for detecting the throttle opening, and a means for detecting the engine speed and the throttle opening. A basic fuel injection amount setting means for setting a basic fuel injection amount; a fully extended detection means for measuring the duration of the fully extended state of the engine based on the engine speed and throttle opening; A fuel injection control device for a two-stroke engine, comprising: an increase correction means for gradually increasing the basic fuel injection amount accordingly. (2) The fuel injection control device for a two-stroke engine according to claim 1, wherein the fully extended detection means determines a state of high engine rotation and a high throttle opening as a fully extended state.