JPH0861115A - Fuel supply quantity controller of internal combustion engine - Google Patents

Abstract

PURPOSE: To properly control a supply quantity of fuel to an internal combustion engine in response to its evaporative characteristics. CONSTITUTION: An intake valve temperature is an initial water temperature THV as same as a cooling water temperature at the time of startup. The intake valve temperature increases almost linearly as the number of ignition increases after the startup. Consequently, the intake valve temperature can be estimated by the initial water temperature THV and the number of the ignition. The evaporative condition of fuel injected from a fuel injection valve can be estimated accurately by the estimated intake valve temperature and the evaporative characteristic of the fuel preliminarily stored, and thereby an appropriate fuel supply quantity can be calculated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel supply amount control device for an internal combustion engine, which controls the fuel supply amount according to the operating state of the internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, as this type of device, a fuel supply means for supplying fuel to the internal combustion engine, which is arranged in the vicinity of an intake valve of the internal combustion engine, and a fuel supply means It is known to include a basic supply amount calculation means for calculating a basic supply amount, and a fuel supply amount correction means for correcting the calculated basic supply amount to obtain a fuel supply amount by the fuel supply means. There is. Also, in this type of device,
For example, as described in JP-B-2-45030,
It has been considered to detect the cooling water temperature of the internal combustion engine and correct the basic supply amount based on the cooling water temperature.

[0003]

However, it is not possible to control the fuel supply amount with sufficient precision as follows only by the correction based on the cooling water temperature. For example, the supplied fuel may not be completely vaporized at the so-called cold start when the internal combustion engine is not yet sufficiently warm. In such a case, when fuel is being supplied to the vicinity of the intake valve where the temperature rises rapidly, the fuel supply amount is increased and corrected according to the evaporation characteristic of the fuel (for example, saturated vapor pressure) corresponding to the temperature of that portion. Is considered to be preferable. However, the cooling water temperature rises much later than the temperature in the vicinity of the intake valve, and does not have a very good correspondence with the temperature in the vicinity of the intake valve (for example, FIG. 5).
reference). Therefore, in this type of device, the fuel supply amount cannot be corrected in accordance with the fuel evaporation characteristic.

Further, since the fuel evaporation characteristic is also influenced by the intake pipe pressure, it is considered preferable to correct the fuel supply amount in consideration of the fuel evaporation characteristic corresponding to the intake pipe pressure. However, conventionally, the intake pipe pressure is simply treated as a parameter corresponding to the intake air amount and the engine speed, and is not corrected in consideration of the evaporation characteristic of the fuel which changes according to the intake pipe pressure.

Further, it is conceivable to correct the fuel supply amount by a map created based on the actual measurement value with reference to the throttle opening etc., but since many other factors are reflected in the actual measurement value data, it is sufficient. Correction accuracy cannot be obtained. Therefore, the present invention has been made for the purpose of providing a fuel supply amount control device capable of satisfactorily controlling the supply amount of fuel to an internal combustion engine according to its evaporation characteristic.

[0006]

In order to achieve the above object, the invention according to claim 1 is arranged near an intake valve of an internal combustion engine, as shown in FIG. 13, and supplies fuel to the internal combustion engine. Fuel supply means for supplying, basic supply amount calculating means for calculating a basic supply amount of fuel according to the operating state of the internal combustion engine, and correction of the calculated basic supply amount for fuel supply by the fuel supplying means. In a fuel supply amount control device for an internal combustion engine, comprising:
Intake valve temperature detecting means for detecting the temperature in the vicinity of the intake valve is provided, and the fuel supply amount correcting means is configured to perform the basic supply based on the detected temperature in the vicinity of the intake valve and the fuel vaporization characteristic stored in advance. The gist is a fuel supply amount control device for an internal combustion engine, which is characterized in that the amount is corrected.

According to a second aspect of the present invention, the intake valve temperature detecting means detects the cooling water temperature of the internal combustion engine and the ignition number detecting means detects the number of ignitions of the internal combustion engine after starting. And an intake air temperature calculating means for calculating the temperature in the vicinity of the intake valve by correcting the cooling water temperature detected at the time of starting the internal combustion engine according to the detected number of ignitions. The gist of the fuel supply amount control device for an internal combustion engine according to claim 1 is.

The present invention further comprises an intake pipe pressure detecting means for detecting the intake pipe pressure of the internal combustion engine, and the fuel supply amount correcting means is detected by the intake valve temperature detecting means. The basic supply amount based on the correction coefficient obtained according to the temperature near the intake valve and the evaporation characteristic of the fuel and the correction coefficient obtained according to the intake tube pressure and the evaporation characteristic of the fuel detected by the intake pipe pressure detecting means. A combustion supply amount control device for an internal combustion engine according to claim 1 or 2, further comprising means for correcting the above.

Further, the invention according to claim 4 is characterized in that the fuel supply amount correcting means corrects the basic supply amount to a predetermined amount or more determined according to the basic supply amount. The gist is the fuel supply amount control device for an internal combustion engine according to any one of Items 3.

[0010]

According to the present invention having the above-mentioned structure, the fuel supply means for supplying fuel is arranged near the intake valve of the internal combustion engine. The basic supply amount calculation means calculates the basic supply amount of fuel according to the operating state of the internal combustion engine, and the fuel supply amount correction means corrects the calculated basic supply amount. Then, the fuel supply means Fuel is supplied to the internal combustion engine based on the corrected supply amount.

Here, the fuel supply amount correcting means corrects the basic supply amount on the basis of the temperature near the intake valve detected by the intake valve temperature detecting means and the fuel evaporation characteristic stored in advance. That is, it is possible to detect the temperature near the intake valve to which the fuel is supplied and correct the basic supply amount based on the evaporation characteristic of the fuel corresponding to the temperature.

According to the second aspect of the invention, the intake valve temperature detecting means corrects the cooling water temperature detected by the cooling water temperature detecting means at the time of starting the internal combustion engine in accordance with the number of ignition times detected by the ignition number detecting means. Then, an intake air temperature calculating means for calculating the temperature in the vicinity of the intake valve is provided. here,
It is known that at the time of starting the internal combustion engine, the cooling water temperature and the temperature in the vicinity of the intake valve are substantially equal, and after the start of the internal combustion engine, the temperature in the vicinity of the intake valve rises substantially linearly according to the number of ignitions. Therefore, in the present invention, the temperature in the vicinity of the intake valve can be accurately detected without adding a new configuration to the conventional device.

According to the third aspect of the present invention, the fuel supply amount correction means detects a correction coefficient in accordance with the temperature near the intake valve detected by the intake valve temperature detection means and the evaporation characteristic of the fuel, and the intake pipe pressure detection. The basic supply amount is corrected based on the intake pipe pressure detected by the means and the correction coefficient obtained according to the evaporation characteristic of the fuel. Therefore, it is possible to correct the fuel supply amount based on the fuel evaporation characteristic according to the intake pipe pressure, and the fuel supply amount is controlled more accurately.

Further, in the invention according to claim 4, the fuel supply amount correcting means corrects the basic supply amount calculated by the basic supply amount calculating means to a predetermined amount or more determined according to the basic supply amount. Therefore, no matter how the temperature in the vicinity of the intake valve changes, the basic supply amount does not fall below the predetermined amount. Therefore, it is possible to properly prevent the basic supply amount from being undercorrected and running out of fuel.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention in a vehicle internal combustion engine will be described below with reference to the drawings. FIG. 1 shows the present invention applied to 4
It is a schematic block diagram showing the structure of the internal combustion engine 1 periphery of a cylinder.
In FIG. 1, an air flow meter 5 is provided in the intake passage 3 of the internal combustion engine 1. The air flow meter 5 directly measures the intake air amount Q and has a built-in potentiometer to generate an output signal of an analog voltage proportional to the intake air amount Q. This output signal is A / of control circuit 10.
It is supplied to the D converter 101. This A / D converter 101
Is a built-in well-known multiplexer which sequentially A / D-converts a plurality of input signals at predetermined timings and outputs the converted signals as one output signal.

Next, the distributor 11 has its axis converted into a crank angle of, for example, 720 ° (hereinafter referred to as 72 °).
Crank angle sensor 1 that generates a pulse signal for reference angle detection (hereinafter referred to as a reference signal) every 0 ° CA)
A crank angle sensor 15 is provided which generates a pulse signal for angle detection (hereinafter referred to as an angle signal) every 3 and 30 ° CA. These reference signal and angle signal are input / output interface (I / O) 1 of the control circuit 10.
02, of which the angle signal is supplied to the interrupt terminal of the CPU 103.

Further, the intake passage 3 is provided with a fuel injection valve 21 for injecting pressurized fuel from the fuel supply system 17 into the vicinity of the intake valve 19 of the internal combustion engine 1 for each cylinder. Further, a water jacket 23 of the cylinder block of the internal combustion engine 1 is provided with a water temperature sensor 25 for detecting the temperature of the cooling water. The water temperature sensor 25 generates an electric signal of analog voltage according to the temperature THW of the cooling water. This output is also supplied to the A / D converter 101.

The exhaust system downstream of the exhaust manifold 27 is provided with a catalytic converter 29 containing a three-way catalyst for simultaneously purifying three harmful components HC, CO, and NOx in the exhaust. Further, the exhaust manifold 27 is provided with an oxygen sensor 31 to generate an electric signal according to the concentration of oxygen components in the exhaust. That is, the oxygen sensor 31 generates different output voltages in the A / D converter 101 of the control circuit 10 depending on whether the air-fuel ratio is leaner or richer than the stoichiometric air-fuel ratio. Further, the throttle sensor 33 is provided in the throttle valve 35 of the intake passage 3. The output signal of the throttle sensor 33 indicating the throttle opening is A of the control circuit 10.
It is supplied to the / D converter 101.

The control circuit 10 is configured as, for example, a microcomputer, and in addition to the A / D converter 101, the input / output interface 102, the CPU 103, the ROM 10
4, a RAM 105, a backup RAM 106, a clock generation circuit 107, a down counter 108, a flip-flop 109, a drive circuit 110, etc. are provided.
The down counter 108, the flip-flop 109, and the drive circuit 110 are for controlling the fuel injection valve 21 as follows.

That is, when the total fuel injection time TAU is calculated by the process described later, the total injection time TAU is preset in the down counter 108 and the flip-flop 109 is also set. As a result, the drive circuit 11
0 starts energizing the fuel injection valve 21. On the other hand, when the down counter 108 counts the clock signal and the carry-out terminal finally becomes the "1" level, the flip-flop 109 is set and the drive circuit 110 stops the energization of the fuel injection valve 21. . That is, the fuel injection valve 21 is energized for the above-mentioned total injection time TAU, and the amount of fuel corresponding to the total injection time TAU is supplied to the combustion chamber of the internal combustion engine 1.

The intake air amount Q detected by the air flow meter 5 and the cooling water temperature THW detected by the water temperature sensor 25.
Is read by an A / D conversion routine executed every predetermined time and stored in a predetermined area of the RAM 105. That is, the value Q and THW in the RAM 105 are updated every predetermined time. The engine speed V is calculated by interruption of the crank angle sensor 15 every 30 ° CA and stored in a predetermined area of the RAM 105.

FIG. 2 is a flow chart showing an A / D conversion routine for reading the cooling water temperature THW. Control circuit 10
Starts this process, the A / D
The output (A / D conversion value) of the converter 101 is read, and in the following step 103, it is determined whether or not the time is the output timing of the cooling water temperature THW by the multiplexer. If it is not the output timing, a negative determination is made, A / D conversion processing (not shown) of another signal is executed, and this routine is ended.

If it is the output timing of the cooling water temperature THW (step 103: YES), it is judged in step 105 whether the A / D conversion value is the first A / D conversion value (ADC) of the cooling water temperature THW. To do. If it is the first ADC, an affirmative decision is made, and in step 107 the A / D converted value is stored in a predetermined area of the RAM 105 as the initial water temperature THV, and the processing ends. If it is not the first ADC (step 105: NO), the cooling water temperature THW is updated by the A / D converted value in step 109, and the process is ended. Through the above processing, the cooling water temperature THW at the time of starting is stored as the initial water temperature THV, and the cooling water temperature THW is stored.
Can be updated and stored at any time.

As is well known, the distributor 11 outputs the signals of the crank angle sensors 13 and 15,
Ignition signals are sequentially output to each cylinder. The control circuit 10 counts the number of ignitions as follows and estimates the temperature in the vicinity of the intake valve 19 based on the result. FIG. 3 is a flowchart showing the intake air temperature estimation routine. The control circuit 10 executes this process as an interrupt process each time the distributor 11 outputs an ignition signal.

When the processing is started, first, step 201
At step 203, the ignition number counter C that is reset at the time of starting is incremented, and in the following step 203, it is determined whether or not the value of the ignition number counter C is equal to or more than a predetermined value KTHV described later. When C ≧ KTHV, after decrementing the ignition number counter C in step 205, C <KT
If it is HV, the process directly proceeds to step 207. In step 207, the estimated intake valve temperature THVI is calculated by the following equation, and the process ends.

THVI = THV + (K1.C / 4) (1) However, the divisor “4” is the number of cylinders, and K1 is a predetermined coefficient. FIG. 4 is a time chart illustrating the behavior of the ignition counter C in the above process. In this example, the ignition signal of a predetermined cylinder is output in synchronization with the reference signal, and then the ignition signal of each cylinder is sequentially output every 180 ° CA based on the angle signal. The ignition counter C increments one by one in synchronization with the fall of each ignition signal and outputs a predetermined value KTHV.
When it reaches, it does not increase any more. In this example, the injection signal for injecting the fuel is output once for each of the two ignition signals. For this reason, the time that the fuel drifts near the intake valve 19 increases, and the fuel can be vaporized better.

Next, FIG. 5 is a graph illustrating the relationship between the number of ignitions and the temperature near the intake valve 19. As shown in the figure, at startup, the intake valve temperature is the initial water temperature THV, which is the same as the cooling water temperature. However, after the start, the intake valve temperature increases almost linearly as the number of ignitions increases. Therefore, the estimated intake valve temperature THV is calculated by the above-mentioned simple equation (1).
I can be calculated.

By the time the number of ignitions reaches the predetermined value KTHV, the intake valve temperature reaches the fuel vaporization stable temperature (K ° C). The fuel vaporization stable temperature is a temperature at which all the injected fuel is vaporized. Therefore, when the intake valve temperature is equal to or higher than K ° C., it is not necessary to refer to the intake valve temperature in the calculation of the fuel injection time described later. Therefore, in this embodiment, C ≧ K
When it becomes THV, the value of the ignition counter C is fixed.

FIG. 6 is a flowchart showing the main routine of this embodiment for calculating the total fuel injection time TAU based on the estimated intake valve temperature THVI calculated as described above. It should be noted that the control circuit 10 executes this processing every predetermined time when the ignition switch is turned on.

When the processing is started, first, at step 301, the basic injection time TINJ is calculated from the engine speed V and the intake air amount Q calculated above based on the map of FIG. Note that the intake air amount coefficient per cylinder represents the ratio of the intake air amount Q in the intake stroke of each cylinder to the cylinder volume of that cylinder. The intake air volume coefficient is denominator 8
The reason why it is expressed as a fraction is to facilitate the editing of the program.

In the following step 303, it is determined whether the estimated intake valve temperature THVI is K ° C. or higher. T
When HVI ≧ K, the routine proceeds to step 305, and the air-fuel ratio feedback correction coefficient is calculated according to the output of the oxygen sensor 31. That is, a correction coefficient larger than 1 is calculated when the air-fuel ratio is excessively biased to the lean side, and a correction coefficient smaller than 1 is calculated when the air-fuel ratio is excessively biased to the rich side. In the following step 307, in order to prevent the cylinder from overheating,
An overheat protection increase coefficient (> 1) is calculated based on a predetermined map or the like. In step 309, the overheat protection increase coefficient is multiplied by the air-fuel ratio feedback correction coefficient to calculate the injection time correction coefficient NK. Further step 3
At 11, the product of the injection time correction coefficient NK and the basic injection time TINJ is set to the total injection time TAU, and the process is temporarily terminated.

That is, when THVI ≧ K, all of the injected fuel is vaporized, so it is not necessary to perform fuel injection control according to the estimated intake valve temperature THVI as described above. Therefore, the basic injection time TINJ is normally corrected according to the air-fuel ratio or the like to obtain the total injection time TAU.

On the other hand, when THVI <K and a negative determination is made in step 303, the routine proceeds to step 313, where the fuel injection time increase coefficient is calculated based on the estimated intake valve temperature THVI based on the table of FIG. In the following step 315, the reduction coefficient of the fuel injection time is calculated based on the table of FIG. 9 according to the intake pressure (kPa). Here, in this embodiment, the intake pressure is calculated based on the map of FIG.
The reduction coefficient is calculated according to the intake pressure.

The intake pressure may be calculated by another method. For example, it is known that there is a relation of P = Q · V between the intake pressure P, the intake air amount Q, and the engine rotation speed V, and the intake pressure P may be calculated from the relation. Further, an intake pressure sensor may be attached to the intake passage 3 to directly detect the intake pressure. In the present embodiment, since the map as shown in FIG. 10 is used, it is possible to calculate the accurate intake pressure in consideration of the opening / closing delay time of the intake valve 19 without providing the intake pressure sensor. That is, the accurate intake pressure can be detected without complicating the configuration.

When the increase coefficient and the decrease coefficient are calculated in steps 313 and 315, the process proceeds to step 317, and the product of both is set as the injection time correction coefficient NK. Continued Step 3
In 19, it is judged whether or not the injection time correction coefficient NK is 1 or more. If it is 1 or more, if it is 1 or less, the injection time correction coefficient NK is reset to 1 and then the process proceeds to step 311. To do. Then, as described above, the total injection time TAU is calculated by NK × TINJ, and the process is temporarily terminated.

That is, depending on the combination of the estimated intake valve temperature THVI and the intake pressure, the injection time correction coefficient NK
May be smaller than 1. This is because the vaporization of the fuel becomes faster with the decrease of the intake pressure and may be completely vaporized before the next injection is performed. In contrast,
The tables in FIGS. 8 and 9 are set on the premise that liquid fuel is present, as will be described later. Therefore, if the increase coefficient and the decrease coefficient calculated from each table are used as they are, the total injection time TAU may be corrected to be shorter than the basic injection time TINJ. Therefore, in this embodiment, the injection time correction coefficient NK is guarded by 1 in the processing of steps 319 and 321 to avoid such a situation.

Next, the table of FIG. 8 is set as follows. The saturated vapor pressure of a fuel at atmospheric pressure (101 kPa) rises with temperature to 72 k at 30 ° C.
It becomes 100 kPa at 40 ° C. and 188 kPa at 60 ° C. The increase coefficient for each temperature is set to be substantially inversely proportional to the saturated vapor pressure at that temperature.

The table of FIG. 9 is set as follows. When the points where the saturated vapor pressure of the fuel becomes equal at each temperature and atmospheric pressure are connected, the diagram illustrated in FIG. 11 is obtained. Dashed lines S1 to S4 in the figure connect points at which the saturated vapor pressures of the fuel coincide with each other. In this diagram, for example, a broken line S passing through 40 ° C and 40 kPa
4 passes through a point of about 67 ° C at atmospheric pressure (101 kPa). The broken line S1 passing through the point of 40 ° C at atmospheric pressure is 6
It passes through a point of about 215 kPa at 7 ° C. Therefore, 40
It can be seen that at kPa, the fuel is easily vaporized more than twice as much as the atmospheric pressure. The table of FIG. 9 is set based on such data.

As described above, when the total injection time TAU is calculated based on the engine speed V, the intake air amount Q, the estimated intake valve temperature THVI, etc., the control circuit 10 executes the fuel injection process of FIG. 12 as another routine. . When you start the process,
In step 401, based on the angle signal, it is determined whether or not the current time is the fuel injection execution timing. If it is not the injection execution timing, there is no need to inject fuel, so other processing (for example, output of an ignition signal) is executed (step 403), and the processing is temporarily terminated. If it is the injection execution timing (step 401: YES), step 405.
Then, it is judged whether the fuel cut condition is satisfied or not. Even if the fuel cut condition is satisfied, there is no need to inject fuel, so the routine proceeds to step 403, and if not satisfied, fuel injection is executed by the following processing.

That is, the process proceeds to step 407, and the total injection time TAU calculated in step 311 (FIG. 6) described above.
Call. In the following step 409, the total injection time TAU is preset in the down counter 108, the fuel injection valve 21 is energized, the amount of fuel corresponding to the total injection time TAU is injected, and the routine proceeds to step 403.

As described above, in this embodiment, the temperature in the vicinity of the intake valve 19 is detected, and the basic fuel injection time TIN is calculated based on the fuel evaporation characteristic corresponding to the estimated intake valve temperature THVI.
J can be corrected. Therefore, even in an operating state in which the supplied fuel is not completely vaporized such as during cold start, the fuel supply amount can be controlled well.

Further, in this embodiment, the estimated intake valve temperature THVI is detected by performing calculation based on the cooling water temperature THW and the number of ignitions of the internal combustion engine 1. Therefore, the temperature in the vicinity of the intake valve can be accurately detected without adding a new configuration to the conventional device. Therefore, the invention according to claim 1 can be applied more easily and inexpensively.

Further, in this embodiment, steps 319 and 3 are performed.
By the process of 21, the total injection time TAU is changed to the basic injection time T
It prevents it from being corrected smaller than INJ. Therefore, the basic injection time TINJ can be corrected to be under-corrected to prevent the fuel shortage.

In the above embodiment, the fuel injection valve 2
1 corresponds to the fuel supply means, and the water temperature sensor 25, the crank angle sensors 13 and 15, and the control circuit 10 correspond to the intake valve temperature detection means. Further, in the processing of the control circuit 10, step 107 and steps 201 to 207 are the intake valve temperature detecting means, and step 301 is the basic supply amount calculating means.
Steps 313 to 319 correspond to the fuel supply amount correcting means, step 107 corresponds to the cooling water temperature detecting means, step 201 corresponds to the ignition frequency detecting means, and step 207 corresponds to the intake valve temperature detecting means. Step 3
In 15, the process of estimating the intake pipe pressure according to FIG. 10 corresponds to the intake pipe pressure detecting means.

Furthermore, the present invention is not limited to the above embodiments, but can be carried out in various modes without departing from the gist of the present invention. For example, as the tables of FIGS. 8 and 9, a plurality of tables may be prepared according to the type of fuel such as regular and high-octane, and the table according to the fuel used may be used. Step 3
In 19 and 321, the injection time correction coefficient NK is guarded by 1, but it may be guarded by a number smaller than 1. Furthermore, the temperature in the vicinity of the intake valve 19 can be detected by various methods other than the method of this embodiment. For example, the intake valve 19
Infrared rays emitted from the vicinity may be detected to detect more directly. In this case, an infrared sensor or the like needs to be newly provided, but the detection accuracy can be improved.

[0046]

As described above in detail, in the invention according to claim 1, the temperature near the intake valve to which the fuel is supplied is detected,
The basic supply amount can be corrected based on the evaporation characteristic of the fuel corresponding to the temperature. Therefore, even in an operating state in which the supplied fuel is not completely vaporized such as during cold start, the fuel supply amount can be controlled well.

According to the second aspect of the present invention, the temperature in the vicinity of the intake valve can be accurately detected without adding a new structure to the conventional device. Therefore, in addition to the effect of the invention described in claim 1, the effect that the invention can be applied more easily and inexpensively can be obtained.

According to the third aspect of the invention, in addition to the effect of the first or second aspect of the invention, the intake pipe pressure is further detected, and the fuel supply amount is determined based on the fuel evaporation characteristic corresponding to the intake pipe pressure. Can be corrected. Therefore, the fuel supply amount can be controlled even better.

Further, in the invention described in claim 4,
In addition to the effects of the inventions described in 3 to 3, it is possible to obtain an effect that the basic supply amount can be undercorrected and the fuel can be prevented from being insufficient.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a configuration around an internal combustion engine of an embodiment.

FIG. 2 is a flowchart showing an A / D conversion routine of the embodiment.

FIG. 3 is a flowchart showing an intake air temperature estimation routine of the embodiment.

FIG. 4 is a time chart illustrating the behavior of the ignition counter of the embodiment.

FIG. 5 is a graph illustrating the relationship between the number of ignitions and the temperature near the intake valve.

FIG. 6 is a flowchart showing a main routine of the embodiment.

FIG. 7 is a map showing the correspondence between engine speed, intake air amount, and basic injection time.

FIG. 8 is a table showing a correspondence between an estimated intake valve temperature and a fuel injection time increase coefficient.

FIG. 9 is a table showing a correspondence between intake pressure and a fuel injection time reduction coefficient.

FIG. 10 is a map showing the correspondence between engine speed, intake air amount and intake pressure.

FIG. 11 is a diagram showing the correspondence between temperature, atmospheric pressure and saturated vapor pressure of fuel.

FIG. 12 is a flowchart showing a fuel injection process of the embodiment.

FIG. 13 is an exemplary diagram of a configuration of the invention according to claim 1;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine 5 ... Air flow meter 10 ... Control circuit 13, 15 ... Crank angle sensor 17 ... Fuel supply system
19 ... Intake valve 21 ... Fuel injection valve 25 ... Water temperature sensor

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area F02P 17/00

Claims (4)

[Claims] 1. A fuel supply means arranged near an intake valve of an internal combustion engine for supplying fuel to the internal combustion engine, and a basic supply quantity for calculating a basic supply quantity of fuel according to an operating state of the internal combustion engine. A fuel supply amount control device for an internal combustion engine, comprising: a calculation unit; and a fuel supply amount correction unit that corrects the calculated basic supply amount to obtain a fuel supply amount by the fuel supply unit. In addition to providing the intake valve temperature detecting means for detecting the temperature of the, the fuel supply amount correcting means, based on the detected temperature in the vicinity of the intake valve and the pre-stored fuel evaporation characteristics,
A fuel supply amount control device for an internal combustion engine, which corrects the basic supply amount. 2. An intake valve temperature detecting means for detecting a cooling water temperature of the internal combustion engine, an ignition frequency detecting means for detecting an ignition frequency of the internal combustion engine after starting, and an internal combustion engine of the internal combustion engine. An intake air temperature calculating means for calculating the temperature in the vicinity of the intake valve by correcting the cooling water temperature detected at the time of start-up according to the detected number of ignitions. Fuel supply control device for internal combustion engine. 3. An intake pipe pressure detecting means for detecting an intake pipe pressure of the internal combustion engine is further provided, and the fuel supply amount correcting means includes a temperature in the vicinity of the intake valve detected by the intake valve temperature detecting means. And a means for correcting the basic supply amount based on a correction coefficient obtained according to the evaporation characteristic of the fuel and a correction coefficient obtained according to the intake tube pressure detected by the intake tube pressure detecting means and the evaporation characteristic of the fuel. 3. The combustion supply amount control device for an internal combustion engine according to claim 1 or 2. 4. The fuel supply amount correction means corrects the basic supply amount to a predetermined amount or more determined according to the basic supply amount, according to any one of claims 1 to 3. Fuel supply control device for internal combustion engine.