JPH0587667B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a fuel injection system for an internal combustion engine, and is particularly suitable for electronically controlling the amount of fuel injected from a vehicle's fuel supply system to an internal combustion engine. The present invention relates to a method of installing an electronic fuel injection system for an internal combustion engine.

(Prior Art) Conventionally, in this type of electronic fuel injection system, various components such as a negative pressure sensor, an intake air amount sensor, a microcomputer, and a fuel injection valve are manufactured separately and then connected to each other. They are attached to each part of the vehicle at different positions. Therefore, when the electronic fuel injection system is assembled to the vehicle, variations in the machining of the various component parts accumulate, and strict requirements are inevitably placed on the precision of the machining of each of these various component parts. As a result, the manufacturing cost of various component parts increases, and since the processing accuracy mentioned above has its own limitations, the assembly accuracy of the entire electronic fuel injection system becomes insufficient and the control accuracy is reduced. There is a problem in that it causes a decline.

As a proposal to deal with this problem, for example, as disclosed in Japanese Patent Application Laid-Open No. 58-32933, an intake air amount sensor, a control device, and a fuel injection valve are integrally attached to the air-fuel mixture generation section of an internal combustion engine. Although there is a method that comprehensively adjusts the variations in these control systems, it is not possible to improve the control accuracy of the control system even with this.

(Object of the Invention) The present invention has been made in response to the above-mentioned problems, and its purpose is to improve the processing accuracy and assembly accuracy of various component parts in an electronic fuel injection system for an internal combustion engine. The aim is to improve control accuracy without improving the

(Structure of the Invention) In achieving the above object, the structural feature of the present invention is that, as illustrated in FIG. A supply valve means 3, a speed detection means 4 that detects the rotational speed of the internal combustion engine 2 and generates a speed signal, and detects a physical quantity generated within the internal combustion engine 2 necessary for regulating the amount of fuel supplied to the engine body 2a. physical quantity detection means 5 which generates a physical quantity signal as a physical quantity signal.
and a calculation means 6 for calculating the fuel supply time according to the speed signal and the physical quantity signal from a predetermined relationship between the rotational speed, the physical quantity, and the fuel supply time corresponding to the fuel supply amount; A storage means 8 for storing a fuel injection rate correction coefficient for multiplying and correcting the invalid injection time of the valve means 3 and the basic fuel supply time so that it matches the required fuel injection amount at that time; A correction means 9 that corrects the result by multiplying the result by the fuel injection rate correction coefficient and adding the invalid injection time to the multiplication result, and a correction means 9 that uses the correction result of the correction means 9 as a signal indicating the open state of the valve means 3. and an output means 7 that generates a signal and applies it to the valve means 3, and the calculation means 6, the storage means 8, the correction means 9, and the output means 7 are assembled before assembly to the engine main body 2a. Further, the valve means 3 is connected to the fuel supply system 1 via the connecting pipe 3a to form an assembly assembly U, and in the state in which this assembly assembly U is constructed,
The relationship between the fuel injection time and the fuel injection amount for the valve means 3 is actually measured, and from this measurement result, the invalid injection time corresponding to the valve means 3 and the basic fuel supply time match the required fuel injection amount at that time. The storage means 8 calculates the fuel injection rate correction coefficient for multiplication correction as follows.
After that, the assembly assembly U is assembled to the engine main body 2a.

(Effects of the Invention) Therefore, in the present invention configured as described above, the fuel injection rate correction coefficient and the invalid injection time of the valve means 3 are determined as described above and stored in the storage means 8, and the correction means 9 6 and storage means 8, the fuel supply time is multiplied by the fuel injection rate correction coefficient and the invalid injection time is added to this multiplication result for correction. Since the correction result is given to the valve means 3 as the output signal, the fuel injection time of the valve means 3 to the engine body 2a is controlled by the processing error and assembly error of each component in relation to the correction result of the correction means 9. As a result, the amount of fuel injected into the engine body 2a can be controlled accurately at all times while effectively solving the problems described in the prior art section of this specification.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings. Figs. 1 to 4 show a four-cylinder internal combustion engine for a vehicle.
2 shows an example in which the present invention is applied to an independent injection type electronic fuel injection system employed in
e, and an electronic control device 30. The water temperature sensor 20a, the negative pressure sensor 20b, and the electronic control device 30 are housed in the housing 12a together with the idle rotation speed control device 14 of the internal combustion engine 10, the pressure regulator 15a, and the distribution pipe 15b. It is integrally provided on the outer wall of the intake pipe section 12 of the internal combustion engine 10 and is assembled to a peripheral wall portion of a cooling water channel 12b led out from the cooling system of the internal combustion engine 10. In such a case, the distribution pipe 15b connects the fuel tank 16 at its inlet via a connecting pipe 16a with a filter 16c and a fuel pump 16b interposed therein.
Each distribution port of this distribution pipe 15b is connected to the supply port of each rubber pipe 17a, 17b, 17c,
Each fuel injection valve 18a, 18b, 18c, 1 assembled to the intake manifold 11 via 17d
8d, respectively. Further, the pressure regulator 15a is connected at its outlet to the inlet of the fuel tank 16 via a connecting pipe 16d. In addition,
The cooling water led out from the cooling system into the cooling waterway 12b serves to prevent the throttle valve 12c provided in the intake pipe portion 12 from freezing.

The water temperature sensor 20a is attached to the peripheral wall of the cooling waterway 12b, detects the temperature of the cooling water in the cooling waterway 12b, and generates a water temperature signal. The negative pressure sensor 20b is fixed to the outer end of a pressure guiding pipe 12d extending from the peripheral wall of the intake pipe section 12 into the casing 30a of the electronic control device 30. The pressure of the air flow (hereinafter referred to as intake flow) that passes through the air cleaner 13a, the intake pipe section 13, the intake pipe section 12, and the intake manifold 11 and is taken into the combustion chamber of the internal combustion engine 10 is detected by receiving it from the impulse pipe 12d. Generated as a pressure signal. The opening sensor 20c is fixed to the peripheral wall of the intake pipe section 12 and is connected to the throttle valve 12.
The opening degree of c is detected and generated as an opening degree signal. The rotation angle sensor 20d detects the rotation angle of the camshaft provided in the distributor 19 of the internal combustion engine 10 at every predetermined rotation angle, and transmits these detection results to the internal combustion engine 1.
A rotation angle signal representing a rotation angle of 0 is sequentially generated. Further, the reference angle sensor 20e detects the reference rotation angle of the camshaft of the distributor 19, and converts this into the reference rotation angle of the internal combustion engine 10 (corresponding to the top dead center of the first piston P in the first cylinder C). ) is generated as a reference signal representing

The electronic control device 30 is supported within the housing 12a at an upper portion thereof in FIG.
The connector 30b fixed to the side wall of the casing 30a of the electronic control device 30 is connected to the housing 12a.
is connected to the rotation angle sensor 20d and the reference angle sensor 20e, and is connected to the ignition switch IG of the vehicle.
It is connected to DC power supply B via. As shown in FIG. 4, this electronic control device 30 includes a constant voltage circuit 31, an A-D converter 32, both waveform shapers 33,
34 is housed in a casing 30a, and a constant voltage circuit 31 is connected to an ignition switch IG via a connector 30b. Therefore, this constant voltage circuit 31 is connected to the ignition switch IG.
It is supplied with power from DC power supply B through the circuit to generate a constant voltage.

The A-D converter 32 is connected within the housing 12a to a conductor extending from the water temperature sensor 20a into the casing 30a through the bottom wall of the casing 30a, and connects the negative pressure sensor 2 within the casing 30a.
It is connected to a conducting wire extending from the opening sensor 20c, and is connected to a conducting wire extending from the opening sensor 20c through the opening of the housing 12a and into the casing 30a through the bottom wall of the casing 30a. However,
The A-D converter 32 receives the water temperature signal from the water temperature sensor 20a, the negative pressure signal from the negative pressure sensor 20b, and the opening signal from the opening sensor 20c through the conductive wires and converts them into digital signals, respectively. Generated as negative pressure signal and digital opening signal. The waveform shaper 33 is connected to the rotation angle sensor 20d via a connector 30b, receives each rotation angle signal from the rotation angle sensor 20d through the connector 30b, sequentially shapes the waveform, and generates a shaped rotation angle signal. On the other hand, the waveform shaper 34 is connected to the reference angle sensor 20e through the connector 30b, receives each reference angle signal from the reference angle sensor 20e through the connector 30b, sequentially shapes the waveform, and generates a shaped reference angle signal.

The electronic control device 30 also includes a rewritable read-on memory 35 (hereinafter referred to as P-ROM 35),
Microcomputer 36 and drive circuit 37a~
37d is housed in the casing 30a. The microcomputer 36 operates in response to a constant voltage from the constant voltage circuit 31, and executes a main control program and an interrupt control program stored therein in accordance with the flowcharts shown in FIGS. 6 and 7, respectively. , is repeatedly executed in cooperation with the A-D converter 32, both waveform shapers 33 and 34, and the P-ROM 35, and during the repetition of such execution,
Each drive circuit 37a to 37d injects fuel into the internal combustion engine 10 from each fuel injection valve 18a to 18d.
The various arithmetic operations necessary to control are performed as described below. In such a case, the interrupt timing for executing the interrupt control program is determined by adjusting the frequency of the shaped rotation angle signal from the waveform shaper 33 using the shaped reference angle signal from the waveform shaper 34 as a reference.
It is defined by a frequency-divided signal formed by dividing the frequency within 6. Note that the frequency division signals are formed at the timing when the internal combustion engine 10 reaches each rotation angle corresponding to the predetermined advance angle value before reaching the top dead center of each cylinder.

P-ROM35 is a plurality of fuel injection rate correction coefficients.
K _a , K _b , K _c , K _d and invalid injection time ta , _{t b} , t _c , t _d
are stored in advance, and each fuel injection rate correction coefficient and invalid injection time are determined as follows. Generally, the fuel injection characteristics of each fuel injection valve 18a, 18b, 18c, 18d for the internal combustion engine 10 are expressed by the following equation.

g=Q(T-t)...(1) However, g: Fuel injection amount (mm ³ /times) Q: Fuel injection rate (mm ³ /ms) T: Fuel injection time (ms) t: Ineffective injection time (ms) Therefore, for the internal combustion engine 10 of each of the fuel injection valves 18a to 18d, the optimal fuel injection characteristics that can obtain the target air-fuel ratio under various operating conditions (such as those that can obtain the target air-fuel ratio under various operating conditions) are determined. When the characteristic indicating the relationship between the fuel injection amount q and the fuel injection time T to obtain the fuel injection amount q was determined through experiments, it was obtained as a straight line A (based on a dashed-dotted line) as shown in FIG. Therefore, the coordinates of the two points on this straight line A (g, T) = (g ₁ , T ₁ ) = (5.3,
2.5) and (g, T) = (g ₂ , T ₂ ) = (46.2, 16.0) into equation (1) to find Q and t using simultaneous equations. As a result, Q = Q ₀ = 3.03 , t=t ₁ =0.75.

Further, when an assembled assembly as shown in FIG. 3 was prepared in advance and the fuel injection characteristics of the assembled assembly of the fuel injection valve 18a were determined by experiment, the results were as shown in straight line B (solid line) as shown in FIG. ) was obtained. Therefore, the coordinates of the two points on this straight line B are (g, T) = (g ₃ , T ₁ ) and (g, T) = (g ₄ , T ₂ )
As a result of substituting Q and t into Equation (1) and finding Q and t using simultaneous equations, the fuel injection rate and invalid injection time in the assembled assembly of the fuel injection valve 18a are Q=Q _a ,
It was obtained as t=t _a . Furthermore, in the same manner, the fuel injection rates Q in the assembled assembly of the fuel injection valves 18b, 18c, and 18d are Q _b , Q _c , and Q _{d ,} respectively.
and fuel injection valves 18b, 18c,
Ineffective injection time t in the assembled assembly of 18d
were obtained as t _b , t _c , and t _d , respectively.

From the above, each fuel injection rate Q _a , Q _b , Q _c ,
In order to match Q _d with the optimal fuel injection rate Q ₀ ,
If we multiply Q _a by (Q ₀ /Q _a ), Q _b by (Q ₀ /Q _b ), Q _c by (Q ₀ /Q _c ), and Q _d by (Q ₀ /Q _d ), we get Good things are understood. In other words, the basic injection time τ to the internal combustion engine 10 (here, τ=T−t,
τ is common to each fuel injection valve 18a to 18d), (Q ₀ /Q _a ), (Q ₀ /Q _b ), (Q ₀ /Q _c ), or (Q ₀ /
Q _d ), each fuel injection valve 18a, 18b,
This means that the basic injection time τ of 18c or 18d can be corrected so as to approach the optimum injection time in relation to the assembled assembly. Therefore, based on this viewpoint, Q ₀ /Q _a =K _a , Q ₀ /Q _b =K _b , Q ₀ /Q _c =K _c ,
Q ₀ /Q _d =K _d is stored in advance in the P-ROM 35 as described above. Moreover, each fuel injection valve 18a,
The invalid injection times of 18b, 18c, and 18d do not need to be corrected for t ₀ , so they are unchanged as t _a , t _b , t _c ,
It is stored in advance in the P-ROM 35 as _td as described above.

Drive circuit 37a, 37b, 37c or 37d
is under the control of the microcomputer 36,
Opening/closing control of the fuel injection valves 18a, 18b, 18c, or 18d is performed. In other words, the fuel injection valve 18a
In cooperation with the drive circuit 37a, the fuel pumped from the fuel tank 16 by the fuel pump 16b is transferred to the filter 16c and the distribution pipe 15.
b, and is received through the rubber pipe 17a and injected into the first cylinder via the intake manifold 11.
Also, the remaining fuel injection valves 18b, 18c or 18
d also receives fuel through the rubber pipe 17b, 17c or 17d under the cooperation of the drive circuit 37b, 37c or 37d, and supplies the second, third or fourth fuel through the intake manifold 11. Inject into the cylinder.

In this embodiment configured as above, when assembling the system of the present invention to the internal combustion engine 10, as described above, each fuel injection valve 18a,
18b, 18c, 18d is _determined , and each fuel injection valve 18a, 18b, 18c, in the assembled assembly shown in FIG. 3 is determined.
The fuel injection rate correction coefficients K _a , K _b , K _c , K _d and invalid injection times ta , t _{b ,} t _c , t _d of 18d are determined, and each fuel injection rate correction coefficient K _a to _{K d} and each The invalid injection times t _a to t _d are stored in the P-ROM 35, and then the intake pipe section 12 of the assembled assembly is assembled between the intake pipe section 13 and the intake manifold 11, and each fuel injection valve 18a is 18d to the intake manifold 11.

In this case, since each of the rubber tubes 17a to 17d has flexibility, each fuel injection valve 18a to 18d can be easily assembled to the intake manifold 11. In addition, a pressure regulator 15a, a distribution pipe 1
5b and the idle rotation speed control device 14 are housed in the housing 12a together with the electronic control device 30 and assembled to the intake pipe portion 12, so that this type of fuel injection system can be constructed compactly. Further, since the water temperature sensor 20a is attached to the cooling water channel 12b within the housing 12a, this type of fuel injection system can be made even more compact.

After completing the assembly in this way, with the ignition switch IG closed, the microcomputer 36 operates in cooperation with the constant voltage circuit 31, and executes the main control program according to the flowchart shown in FIG. Start at step 40 and proceed to step 41
After initialization, the operation of cycling through both steps 42 and 43 is repeated, and the interrupt execution of the interrupt control program is executed at the seventh step every time each frequency division signal is formed in cooperation with both waveform shapers 33 and 34. The process is repeated according to the flowchart shown in the figure, and the vehicle is equipped with internal combustion engine 1.
It is assumed that the vehicle starts with a start of 0. In such a case, the microcomputer 36 is required to perform calculations that cycle through both steps 42 and 43 of the main control program.
In step 42, the digital water temperature signal and the digital opening signal generated by cooperation with the water temperature sensor 20a and the opening sensor 20c are repeatedly input from the A-D converter 32, and in step 43, the digital water temperature signal and the digital opening signal are inputted repeatedly to the internal combustion engine 10. A water temperature correction value _Kw and an excessive correction value K〓 necessary for correcting the basic injection time τ corresponding to the basic injection amount of fuel are repeatedly calculated based on the respective values of the digital water temperature signal and the digital opening signal in step 42.

In such a state, when interrupt execution is started in step 50 of the interrupt control program, the microcomputer 36 in step 51 calculates each shaped rotation generated by the waveform shaper 33 in cooperation with the rotation angle sensor 20d. The rotational speed N of the internal combustion engine 10 is calculated based on the angle signal, and in step 52, a digital negative pressure signal generated by cooperation with the negative pressure sensor 20b is input from the A-D converter 32, and in step 53, Basic injection time τ, rotational speed N and impulse pipe 12
The basic injection time τ is calculated according to the rotational speed N and the digital negative pressure signal at both steps 51 and 52 based on the map representing the relationship between the negative pressures in d. The latest water temperature correction value _Kw and the transient correction value K〓 are multiplied together, and the multiplication result is set as the corrected basic injection time _τa .

Therefore, if the current injection cylinder of the internal combustion engine 10 is the first cylinder due to the relationship between the shaping reference angle signal from the waveform shaper 34 and the shaping rotation angle signal from the waveform shaper 33, the microcomputer 36 steps the computer program 55
Proceed to step 56a, multiply the corrected basic injection time _{τ a} in step 54 by the fuel injection rate correction coefficient K a in the P-ROM 35, and proceed to the next step 57a.
In, the invalid injection time in P-ROM35
t _a is added to the multiplication result τ _a K _a in step 56a, and the addition result is set as the optimum fuel injection time τ ₀ of the fuel injection valve 18a in its built-in down counter in step 58a.

Then, the down counter of the microcomputer 36 sets the fuel injection time τ ₀ and simultaneously generates this as the first output signal and starts counting down. Next, the drive circuit 37a generates a first drive signal in response to the first output signal from the microcomputer, and in response, the fuel injection valve 18a opens and the fuel pump 1 is discharged from the fuel tank 16.
6b, filter 16c, distribution pipe 15b, and rubber pipe 17a, the fuel is received and begins to be injected into the first cylinder of internal combustion engine 10. Thereafter, when the down counter of the microcomputer 36 stops generating the first output signal upon completion of its down count, the drive circuit 37a stops generating the first drive signal, and in response, the fuel injection valve 18a closes to stop fuel injection to the first cylinder of the internal combustion engine 10.

Further, if the injection cylinder of the internal combustion engine 10 is determined to be the second cylinder in step 55 described above, the microcomputer 36 advances the computer program from step 55 to step 56b, and sets the fuel injection rate correction coefficient in the P-ROM 35.
K _b is the corrected basic injection time τ _a in step 54
In the next step 57b, P-
Set the invalid injection time t _b in the ROM35 to step 5.
While adding to the multiplication result τ _a K _b in 6b,
The result of this addition is set in the down counter at step 58b as the optimum fuel injection time τ ₀ for the fuel injection valve 18b.

Then, the down counter of the microcomputer 36 generates this as a second output signal and starts counting down at the same time as the fuel injection time τ ₀ is set. Next, the drive circuit 37b generates a second drive signal in response to the second output signal from the microcomputer 36, and in response, the fuel injection valve 18b opens and the fuel pump 16b, filter 16c, The fuel is received through the distribution pipe 15b and the rubber pipe 17b and begins to be injected into the second cylinder of the internal combustion engine 10. Thereafter, when the down counter of the microcomputer 36 stops generating the second output signal due to the end of its down count, the drive circuit 37b stops generating the second drive signal, and in response, the fuel injection valve 18b is closed to stop fuel injection to the second cylinder of the internal combustion engine 10.

Further, if the injection cylinder of the internal combustion engine 10 is determined to be the third cylinder in step 55 described above, the microcomputer 36 advances the computer program from step 55 to step 56c, and sets the fuel injection rate correction coefficient in the P-ROM 35.
K _c is corrected basic injection time τ _a in step 54
In the next step 57c, P-ROM
The invalid injection time t _c at step 35 is added to the multiplication result τ _a K _c at step 56c, and the addition result is set in the down counter at step 58c as the optimum fuel injection time τ ₀ for the fuel injection valve 18c.

Then, at the same time as the fuel injection time τ ₀ is set, the down counter of the microcomputer 36 generates this as a third output signal and starts counting down. Next, the drive circuit 37c generates a third drive signal in response to the third output signal from the microcomputer 36, and in response to this, the fuel injection valve 18c opens and the fuel pump 16b, filter 16c, The fuel is received through the distribution pipe 15b and the rubber pipe 17c and begins to be injected into the third cylinder of the internal combustion engine 10. Thereafter, when the down counter of the microcomputer 36 stops generating the third output signal upon completion of its down count, the drive circuit 37c stops generating the third drive signal, and in response, the fuel injection valve 18c closes to stop fuel injection to the third cylinder of the internal combustion engine 10.

Also, the internal combustion engine 1 in step 55 described above
If the discrimination with respect to the injection cylinder 0 is the fourth cylinder, the microcomputer 36 advances the computer program from step 55 to step 56d, and sets the fuel injection rate correction coefficient in the P-ROM 35.
K _d is multiplied by the corrected basic injection time τ _a in step 54, and in the next step 57d, the P-ROM3
The invalid injection time t _d in step 5 is added to the multiplication result τ _a K _d in step 56c, and the addition result is set in the down counter in step 58d as the optimum fuel injection time τ ₀ of the fuel injection valve 18d.

Then, at the same time as the fuel injection time τ ₀ is set, the down counter of the microcomputer 36 generates this as the fourth output signal and starts counting down. Next, the drive circuit 37d generates a fourth drive signal in response to the fourth output signal from the microcomputer 36, and in response, the fuel injection valve 18d opens and the fuel pump 16b, filter 16c, The fuel is received through the distribution pipe 15b and the rubber pipe 17d and begins to be injected into the fourth cylinder of the internal combustion engine 10. Thereafter, when the down counter of the microcomputer 36 stops generating the fourth output signal due to the end of its down count, the drive circuit 37d stops generating the fourth drive signal, and in response, the fuel injection valve 18d closes to stop fuel injection to the fourth cylinder of the internal combustion engine 10.

As understood from the above explanation, the third
Each fuel injection valve 18 in the assembled assembly shown in the figure.
a, 18b, 18c, 18d fuel injection rate correction coefficients K _a , K _b , K _c , K _d and invalid injection times ta , t _{b ,} t _c ,
t _d is determined as described above and stored in the P-ROM 35 in advance, and then the intake pipe section 12 is assembled between the intake pipe section 13 and the intake manifold 11 in the assembled assembly, and each fuel Injection valve 18
a to 18d are assembled to the intake manifold 11 by utilizing the flexibility of each rubber tube 17a to 17d, and in connection with the selective cylinder discrimination in step 55, the corrected basic injection time τ _{a is} determined in step 54.
is corrected to (τ _a K _a +t _a ) in both steps 56a and 57a, and (τ _a K _b +t _b ) in both steps 56b and 57b, based on the stored contents of the P-ROM 35. By correcting (t _a K _c +t _c ) in steps 56c and 57c, or by correcting (t _a K _d +t _d ) in both steps 56d and 57d, each of these correction results (τ _a K _a +t _a ) , (τ _a K _b +t _b ),
(τ _a K _c +t _c ) or (τ _a K _d +t _d ) as the first, second, third, or fourth output signal of the fuel injection valve 18a,
18b, 18c, or 18d, this type of independent injection type electronic fuel injection system can be configured compactly in conjunction with the above-mentioned assembly assembly, and the fuel injection valves 18a, 18
The independent injection time of b, 18c or 18d to the internal combustion engine 10 is the above-mentioned correction result (τ _a K _a +t _a ), (τ _a K _b
+t _b ), τ _a K _c +t _c ), or (τ _a K _d + t _d ), it is possible to achieve high accuracy without being affected by processing errors and cumulative assembly errors of each component of the assembly assembly. As a result, the independent fuel injection amount to the internal combustion engine 10 can be accurately controlled at all times while effectively solving the problems described in the prior art section of this specification.

In the above embodiment, the pressure regulator 15a, the distributor 15b, the fuel tank 16, the connecting pipe 16a, the fuel pump 16b, and the filter 16c correspond to the fuel supply system of the present invention, and the rubber pipes 17a to 17b correspond to the connection of the present invention. The fuel injection valves 18a to 18d correspond to the valve means of the present invention, the components inside the housing 12a correspond to the assembled assembly of the present invention, and the P-
The ROM 35 corresponds to the storage means of the present invention.

Further, step 51 in FIG. 7 corresponds to the speed detecting means of the present invention, step 52 corresponds to the physical quantity detecting means of the present invention, steps 53 and 54 correspond to the calculating means of the present invention, and steps 56a to 56d ,
57a to 57d correspond to the correction means of the present invention, steps 58a to 58d and drive circuits 37a to 37
d corresponds to the output means of the present invention.

In the above embodiment, an example in which the present invention was applied to an independent injection type electronic fuel injection system was described, but instead of this, the present invention could be applied to a synchronous injection type electronic fuel injection system. You may.

In addition, in the above embodiment, the P-ROM 35
Although an example has been described in which the fuel injection rate correction coefficients K _a to _{K d} and the invalid injection time t _a to t _d are stored, instead of this, the fuel injection rate correction coefficients K _a to _{K d} and the invalid injection time t can be stored. _a to t _d , for example, on microcomputer 3
6 may be stored and implemented.

Further, in the above embodiment, an example in which the present invention is applied to an independent injection type electronic fuel injection system for a 4-cylinder internal combustion engine has been described, but the present invention is not limited to this, and is applicable to various types of internal combustion engines such as 6-cylinder and 8-cylinder engines. The present invention may be applied to an independent injection type electronic fuel injection system for an internal combustion engine. May be implemented.

Furthermore, in the embodiment, each fuel injection valve 1
The fuel injection rates Q _a to Q _d and the invalid injection times t _{a to} t _d in the assembly assemblies 8a to 18d are determined by actual measurements and are a straight line that satisfies equation (1) (as illustrated in FIG. 5).
I tried to find it by setting up simultaneous equations based on
Instead, the amount of fuel injected per unit time under the fuel injection operation of each fuel injection valve 18a, 18b, 18c, 18d in the assembled assembly is actually measured, and these actual measurement results are used for each fuel injection rate.
Q _a , Q _b , Q _c , Q _d are determined, and the driving pulse a (see Fig. 8) with pulse width T _i is applied to each fuel injector 18.
a, 18b, 18c, and 18d to cause each of these fuel injection valves 18a to 18d to perform a valve opening operation, and to open each fuel injection valve 18a to 18d.
The amount of displacement of each fuel injection valve 18a to 18a is measured as a waveform b (illustrated in FIG. 8) over time.
In relation to the phase difference between both waveforms a and b, each invalid injection time t _a to t _d under the assembled assembly of 18d is expressed as t _a , t _b , t _c or t _d = t _af It may also be obtained by actual measurement as −t _ar = T _i −t _e .

[Brief explanation of the drawing]

1 and 2 are general views showing an example in which the present invention is applied to an independent injection type electronic fuel injection system for a four-cylinder internal combustion engine, FIG. 3 is an enlarged sectional view of the main parts of the present invention, and FIG. The figure is a block diagram showing the electronic circuit configuration of the fuel injection system of Fig. 1, Fig. 5 is a characteristic diagram showing the relationship between fuel injection time T and fuel injection amount g, and Figs. 6 and 7 are as shown in Fig. 4. FIG. 8 is a flowchart showing the action of the microcomputer in FIG. 8, a waveform diagram of the valve opening operation of the fuel injection valve, and FIG. 9 is a diagram corresponding to the configuration of the invention described in the claims. Explanation of symbols, 10...Internal combustion engine, 12...Intake pipe section, 16...Fuel tank, 17a to 17d...
Rubber pipe, 18a to 18d...Fuel injection valve, 20b
... Negative pressure sensor, 20d ... Rotation angle sensor, 35
...P-ROM, 36...Microcomputer, 37a to 37d...Drive circuit.

Claims (1)

[Scope of Claims] 1. A valve means that receives fuel from a fuel supply system in an open state and supplies it to the engine body of the internal combustion engine; and a speed detection means that detects the rotational speed of the internal combustion engine and generates a speed signal. , physical quantity detection means for detecting a physical quantity generated in the internal combustion engine necessary for regulating the amount of fuel supplied to the engine body and generating a physical quantity signal; calculation means for calculating the fuel supply time according to the speed signal and the physical quantity signal from the relationship between corresponding fuel supply times; a storage means for storing a fuel injection rate correction coefficient for multiplication correction to match the injection amount; and a storage means for multiplying the calculation result of the calculation means by the fuel injection rate correction coefficient and adding the invalid injection time to this multiplication result. and an output means for generating a correction result of the correction means as a signal representing the open state of the valve means and applying it to the valve means, before assembly to the engine main body. The calculation means, the storage means, the correction means, the output means, and the valve means are assembled to the unit, and the valve means is further connected to the fuel supply system via a connecting pipe to form an assembled assembly. , With this assembled assembly configured, the relationship between the fuel injection time and the fuel injection amount for the valve means is actually measured, and from this measurement result, the invalid injection time corresponding to the valve means and the basic fuel supply time are determined. determines a fuel injection rate correction coefficient for multiplying and correcting it so that it matches the required fuel injection amount at that time and stores it in the storage means, and then assembles the assembly assembly to the engine main body. A method of installing a fuel injection system for an internal combustion engine featuring features.