JP2013113242A - Fuel injection control device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel injection control device for an internal combustion engine, improving startability and preventing exhaust gas degradation in starting.SOLUTION: This fuel injection control device for the internal combustion engine includes: a first injection timing calculation means 206 for calculating second and succeeding fuel injection timing after beginning of starting of the internal combustion engine based on a result specified by a crank position specifying means 205; a second injection timing calculation means 207 for calculating initial fuel injection timing after the beginning of the starting based on the specified result, the second timing being later than the first injection timing; a fuel injection timing selection means 208 for selecting either the injection timing calculated by the first injection timing calculation means or the injection timing calculated by the second injection timing calculation means based on the stopped position of the internal combustion engine stored in a stopped position detection/storage means 203 and a determination result by a starting determination means 204; and a fuel injection means 209 for injecting fuel at the selected fuel injection timing.

Description

  The present invention relates to fuel injection control for an internal combustion engine, and more particularly, to a fuel injection control device for an internal combustion engine that controls fuel injection timing for early start-up of the internal combustion engine.

Japanese Patent Application Laid-Open No. 6-185387 (Patent Document 1) discloses a “crank angle sensor that generates a crank angle signal at every predetermined crank angle accompanying rotation of a crankshaft or a camshaft of a multicylinder internal combustion engine, and a multicylinder internal combustion engine. Cylinder discrimination sensor that generates a cylinder discrimination signal for each specific position of a specific cylinder accompanying rotation of the crankshaft or camshaft of the engine, an injector that injects fuel into the intake system of the multi-cylinder internal combustion engine, and start of the multi-cylinder internal combustion engine Asynchronous fuel injection at start is started by back-calculation using the crank angle signal of the crank angle sensor when detecting the cylinder discrimination signal of the cylinder discrimination sensor and the asynchronous discrimination means at the start of the engine. The start asynchronous injection timing calculation means for obtaining the end timing and the start asynchronous injection timing calculation means The fuel injection control apparatus "is shown that includes a fuel injection control means for causing the synchronous injection at the start from the injector into the cylinder is determined that the intake is completed into the combustion chamber of the injected fuel.
That is, the conventional fuel injection control device for an internal combustion engine disclosed in Patent Document 1 performs asynchronous injection to all cylinders at the start of engine start, and then performs synchronous injection from the cylinder in which the fuel of asynchronous injection enters the cylinder. Is what you do.

Japanese Patent Laid-Open No. 7-54691 (Patent Document 2) states that “at the beginning of cranking of an internal combustion engine, asynchronous injection control means executes asynchronous injection that is not synchronized with the intake stroke of each cylinder, and In a fuel injection control device of an internal combustion engine that executes synchronous injection synchronized with the intake stroke of each cylinder by synchronous injection control means after cylinder discrimination for determining the crank position is completed by the cylinder discrimination means, cylinder discrimination by the cylinder discrimination means There is shown a fuel injection control device for an internal combustion engine comprising cylinder selection means for selecting a cylinder on which asynchronous injection is executed by the asynchronous injection control means based on the state.
That is, the conventional fuel injection control device for an internal combustion engine disclosed in Patent Document 2 selects a cylinder that performs asynchronous injection at the start of start based on the cylinder discrimination state and performs asynchronous injection.

JP-A-6-185387 JP-A-7-54691

FIG. 26 is a time chart for explaining an operation example of the conventional fuel injection control device for an internal combustion engine described in Patent Document 1.
The operation of the conventional fuel injection control device for an internal combustion engine described in Patent Document 1 will be described below with reference to FIG. 26 (FIG. 7 of Patent Document 1).
After the starter signal a is turned on at the cranking start position, the fuel is started asynchronously at the time of t1 at the time of starting the fuel.
When the cylinder discrimination signal is detected at the timing t3, the fuel is synchronously injected at the synchronous injection timing t4. This synchronous injection is performed on the cylinders (1 cylinder and 3 cylinders) in which the asynchronous injection at the start is sucked into the cylinders, and the cylinders (4 cylinders and 2 cylinders) in which the asynchronous injection at the start is not sucked into the cylinders. ) Is not done. Therefore, it is possible to prevent the starting failure that occurs because the fuel for both the asynchronous injection and the synchronous injection is sucked into the cylinder at a single suction timing and becomes an excessive amount of fuel.

However, since asynchronous injection is performed for the three cylinders in the exhaust stroke before the valve overlap at timing t10, the valve overlap at timing t10 (that is, when the exhaust valve and the intake valve are open simultaneously). Asynchronously injected fuel flows out into the exhaust pipe.
Therefore, there has been a problem that start-up failure due to combustion failure occurs due to deterioration of exhaust gas due to mixing of unburned gas into exhaust gas and insufficient amount of fuel staying in the cylinder.

FIG. 27 is a flowchart for explaining an operation example of a conventional fuel injection control device for an internal combustion engine described in Patent Document 2.
The operation of the conventional fuel injection control apparatus for an internal combustion engine described in Patent Document 2 will be described below with reference to FIG. 27 (FIG. 11 of Patent Document 2).
In S11 (step 11), when cylinder discrimination is completed (XTDCEG = 1) and the crank position counter is TDC (C = 0) of a specific cylinder, asynchronous injection is not performed and asynchronous injection is completed in S14 ( XSTASY = 1). TDC is “TopDead C”.
abbreviation of “enter”.
In S12, when asynchronous injection is not completed (XSTASY = 0), cylinder discrimination is completed (XTDCEG = 1), and the crank position counter is TDC (C = 12) of another specific cylinder, it is determined in S15. The cylinder (S15A, S62B, S36A, S41B, S24A, S53B) is subjected to fuel injection eight times the basic injection amount (TAU × 8), and asynchronous injection is completed (XSTASY = 1).

In S13, asynchronous injection is not completed (XSTASY = 0) and the cranking counter is 6 or more (E ≧ 6), that is, whether the crank angle signal is counted 6 times or more every 30 deg, and whether the crank angle is rotated 180 deg or more If it is determined, fuel injection is performed 8 times as much as the basic injection amount (TAU × 8) in other determined cylinders (S15A, S62B, S41B, S24A, S53B) in S16, and asynchronous injection is completed (XSTASY) = 1).
As described above, since it is not possible to perform asynchronous injection unless the cylinder discrimination is completed by the TDC signal after the cranking is started or the crank angle is rotated by 180 degrees or more, there is a problem that it takes time to start.

  The present invention has been made in order to solve the problems of the conventional fuel injection control device for an internal combustion engine, and can improve startability and prevent exhaust gas deterioration during start-up. An object of the present invention is to provide a fuel injection control device for an internal combustion engine.

In the fuel injection control device for an internal combustion engine according to the present invention, crank angle detection means for detecting a crank angle of the internal combustion engine, cam angle detection means for detecting the cam angle of the internal combustion engine, and the crank angle detection means detect the crank angle detection means. Stop position detection / storage means for detecting and storing the stop position of the internal combustion engine based on the crank angle, and determining start of the internal combustion engine from the stop position based on the crank angle detected by the crank angle detection means Starting determination means, crank position specifying means for specifying a crank position of the internal combustion engine based on a crank angle detected by the crank angle detecting means and a cam angle detected by the cam angle detecting means, and the crank position specifying First injection timing calculation means for calculating a fuel injection timing for the second and subsequent times after starting of the internal combustion engine based on a result of specifying the means; A second injection timing calculating means that is later than the first injection timing for calculating the first fuel injection timing after the start of the internal combustion engine based on the specifying result of the crank position specifying means, and the stop position detecting / storing means A fuel for selecting one of the injection timings calculated by the first injection timing calculating means or the second injection timing calculating means based on the stop position of the internal combustion engine and the determination result of the start determining means stored in An injection timing selection means and a fuel injection means for injecting fuel at the fuel injection timing selected by the fuel injection timing selection means.

  According to the present invention, the internal combustion engine is started by retarding the initial fuel injection timing at the start within a range in which the fuel injected in the intake stroke can be sucked into the cylinder from the second and subsequent injection timings. The exhaust gas at the start can be prevented from deteriorating.

1 is a diagram illustrating an overall configuration of a fuel injection control device for an internal combustion engine according to the present invention. 1 is a block diagram showing a functional configuration of a fuel injection control device for an internal combustion engine according to Embodiment 1. FIG. It is a figure for demonstrating the output of a crank angle sensor. It is a figure for demonstrating the output of a crank angle sensor. It is a figure for demonstrating the output of a crank angle sensor. It is a figure for demonstrating the output of a crank angle sensor. It is a flowchart which shows the process performed for the first time when an ignition switch is turned ON and power is supplied to ECU. It is a flowchart which shows the process performed for every falling edge of a crank angle sensor output signal. It is a flowchart which shows the process performed for every rising edge of a crank angle sensor output signal. It is a flowchart which shows the detailed process of a missing tooth detection and crank counter value specification. It is a flowchart which shows the count-up process of a crank counter. It is a flowchart which shows the countdown process of a crank counter. It is a flowchart which shows the interruption process performed for every falling edge of a cam angle sensor signal. It is a flowchart which shows the specific process of a crank counter value. It is a flowchart which shows the correction process of a crank counter value. It is a flowchart which shows a stop mode determination process. It is a flowchart which shows the process performed for every falling edge of a crank angle sensor signal in the fuel injection at the time of starting. 3 is a timing chart showing the operation of the internal combustion engine fuel injection control apparatus according to Embodiment 1; It is a timing chart which shows operation | movement when not delaying initial fuel injection timing. 6 is a flowchart showing a fuel injection process at start-up according to the second embodiment. 10 is a flowchart showing a fuel injection process at start-up according to Embodiment 3. It is a figure which shows the retard side injection start timing T1. It is a figure which shows the retard side injection start timing T2. It is a figure which shows the retard side injection start timing T3. It is a flowchart which shows the improvement plan of the fuel-injection process at the time of starting. 6 is a time chart for explaining an operation example of a conventional fuel injection control device for an internal combustion engine disclosed in Patent Document 1; 6 is a flowchart for explaining an operation example of a conventional fuel injection control device for an internal combustion engine disclosed in Patent Document 2;

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a diagram showing an overall configuration of a fuel injection control device for an internal combustion engine (also referred to as an engine) according to the present invention.
In FIG. 1, 101 is an internal combustion engine, 102 is an air cleaner for purifying air taken in by the internal combustion engine, 103 is an intake pipe, 104 is a throttle valve for adjusting the amount of air taken in by the internal combustion engine, and 105 is an intake pipe downstream of the throttle valve. A pressure sensor for measuring the pressure of the engine, 106 is an injector for supplying fuel to the air taken in by the internal combustion engine to form an air-fuel mixture, 107 is an exhaust pipe, and 108 is a front for measuring the remaining amount of exhaust gas discharged from the internal combustion engine. An O2 sensor 109 is a rear O2 sensor that measures the amount of air remaining in the exhaust gas after passing through the catalyst (three-way catalyst), and 110 is a harmless CO2, H2O for HC, CO, and NOx, which are harmful components of the exhaust gas. A three-way catalyst for converting to 111, an ignition coil 111 for generating a high voltage in the secondary coil by energizing / cutting off the current in the primary coil, 112 An ignition plug that generates sparks by a high voltage generated by an ignition coil, 113 is a cam angle sensor that generates a cam angle signal, and 114 is a cam angle sensor plate in which a protrusion or a recess is formed for generating a signal by the cam angle sensor. , 115 is a crank angle sensor for generating a crank angle signal, 116 is a crank angle sensor plate having protrusions or depressions for generating a signal by the crank angle sensor, 117 is cooling water for cooling the internal combustion engine, 118 Is a water temperature sensor for detecting the temperature of the cooling water 117.
Reference numeral 119 inputs signals from the cam angle sensor 113, the crank angle sensor 115, the pressure sensor 105, the front O2 sensor 108, the rear O2 sensor 109, the water temperature sensor 118, etc., and calculates the fuel injection amount, the ignition timing, and the like. The control unit (hereinafter referred to as ECU) that outputs signals to the injector 106 and the ignition coil 111.

FIG. 2 is a block diagram showing a functional configuration of the fuel injection control device for the internal combustion engine according to the first embodiment.
In FIG. 2, reference numeral 201 denotes crank angle detection means, which is composed of the crank angle sensor 115 and the crank angle sensor plate 116 shown in FIG.
Reference numeral 202 denotes a cam angle detecting means, which includes a cam angle sensor 113 and a cam angle sensor plate 114.
Reference numeral 203 denotes stop position detection / storage means, and a crank counter in the ECU 119 plays a role.
204 is a start determination means, and the start mode determination determined in the ECU 119 plays the role.
205 is a crank position specifying means for specifying the crank position based on signals from the crank angle sensor 115 and the cam angle sensor 113.
Reference numeral 206 denotes first injection timing calculation means (first injection timing calculation means), which calculates (calculates) the fuel injection timings for the second and subsequent times after the start of the internal combustion engine.
Reference numeral 207 denotes second injection timing calculation means (second injection timing calculation means), which calculates (calculates) the first fuel injection timing after starting the internal combustion engine.
208 is a fuel injection timing selection means, which selects the first or second injection timing as the first or second injection after the start of the start, and switches the fuel injection timing.
A fuel injection unit 209 performs fuel injection at the timing selected by the fuel injection timing selection unit 208.

3 to 6 are diagrams for explaining the output of the crank angle sensor 115.
3 and 4 show the case where the rotation direction of the crank angle changes from normal rotation to reverse rotation, and FIGS. 5 and 6 show the case where the rotation direction of the crank angle changes from reverse rotation to normal rotation.
3 and 5 show the case where the crank angle identified by the ECU 119 is at the correct timing, and FIGS. 4 and 6 show the case where the crank angle identified by the ECU 119 deviates from the correct timing.
The numbers given to the protrusions of the crank angle sensor plate are numbers for explaining the correspondence between the protrusions of the crank angle sensor plate and the crank angle sensor signal, and are different from the crank counter values shown in FIGS. .

The crank angle sensor plate shown in FIG. 3A is a flat development of the crank angle sensor plate 116 of FIG. 1, and the numerical values “1”, “2”, and “3” are the respective teeth (that is, Projection).
The rotation direction shown in FIG. 3B indicates that the crank angle sensor is moving in the direction of the arrow as the crank angle sensor plate 116 rotates. Between the crank angle sensor plate “2” and “3”, the rotation is changed from normal rotation to reverse rotation.
The arrows shown in FIG. 3 (c) indicate the crank angle rotation direction along the rotation direction of FIG. 3 (b). It shows that the rotation direction is reversed between the time points E and F before the rotation direction is reversed, and the rotation direction is reversed after the rotation direction is reversed.
FIG. 3D is an image of the teeth of the crank angle sensor in the forward or reverse state developed from the left to the right on the time axis image.
FIG. 3 (e) shows the output signal of the crank angle sensor for the crank angle sensor plate of FIG. 3 (d).
FIG. 3F shows a time point.

At time A, the output signal of the crank angle sensor 115 is inverted from low to high due to a change in magnetic flux caused by the protrusion (also referred to as a tooth) “1” of the crank angle sensor plate approaching the crank angle sensor 115.
At the time point B, the center of the protrusion “1” of the crank angle sensor plate 116 has passed through the crank angle sensor 115, so that the output signal of the crank angle sensor 115 is reversed from High to Low.
During forward rotation, the point at which the output signal of the crank angle sensor 115 reverses from High to Low (falling edge) is the effective edge.
Time C and time D are when the next protrusion “2” of the crank angle sensor plate 116 passes through the crank angle sensor 115, and the operations are the same as those at time A and time B.

Time E is the inversion of the crank angle sensor output signal from Low to High due to the next protrusion “3” of the crank angle sensor plate 116 approaching the crank angle sensor 115, and the operation is the same as at time A and time C. It is.
At time point F, the projection “3” of the crank angle sensor plate 116 moves away from the crank angle sensor 115 due to the reverse rotation, so that the output signal of the crank angle sensor 115 is reversed from High to Low.
During reverse rotation, the output voltage on the Low side becomes higher than during forward rotation. (Low level at forward rotation = 0v, Low level at reverse rotation = 2.5v)
At the time point G, the output signal of the crank angle sensor 115 is reversed from low to high because the center of the protrusion “2” of the crank angle sensor plate 116 has passed the crank angle sensor 115 due to reverse rotation. During reverse rotation, the rising edge becomes the effective edge.
At time H, the output signal of the crank angle sensor 115 turns from High to Low when the protrusion “1” of the crank angle sensor plate 116 approaches in reverse.

In this way, by using the crank angle sensor in which the low level of the output signal of the crank angle sensor 115 is different between forward rotation and reverse rotation, the falling to the low level (0v) state is an effective edge, and the low level is high. By setting the rising edge from the state (2.5v) as an effective edge, forward rotation and reverse rotation can be counted, respectively.
The arrows in the sensor output signal (e) in FIGS. 3 to 6 represent the effective edges shown for the sake of easy understanding for explanation, and are not superimposed on the sensor output signal. .
In the process of stopping the engine, if the compression pressure of the cylinder is overcome and the compression top dead center cannot be passed, the engine is reversed by swinging back.

FIG. 4 shows a case where the crank angle identified by the ECU 119 deviates from the correct timing when turning from normal rotation to reverse rotation.
From time A to time D is the same as FIG.
At the time point E, the crank angle sensor passes through the center of the protrusion “2” of the crank angle sensor plate by reverse rotation, so that the crank angle sensor signal is inverted from Low to High as shown in FIG.
At the time point F, the protrusion “1” of the crank angle sensor plate 116 approaches the crank angle sensor 115 due to the reverse rotation, so that the output signal of the crank angle sensor 115 is reversed from High to Low.
The time point E is originally an effective edge, but rises from a low level (0v) state, so that it is not determined as an effective edge, and miscounting (count missing) of the crank angle sensor signal occurs.

FIG. 5 shows an output signal of the crank angle sensor 115 when the rotation is reversed to the forward rotation.
At time A, the projection “3” of the crank angle sensor plate 116 approaches the crank angle sensor 115, so that the output signal of the crank angle sensor 115 is reversed from High to Low. Since it is reversed, the Low level is high (2.5 v).
At time B, the center of the protrusion “3” of the crank angle sensor plate 116 has passed through the crank angle sensor 115, so that the output signal of the crank angle sensor 115 is inverted from low to high as shown in FIG. 5 (e). To do.
At the time of reverse rotation, the point at which the output signal of the crank angle sensor 115 reverses from Low to High (rising edge) becomes an effective edge.
Time C and time D are the same as time A and time B when the next protrusion “2” of the crank angle sensor plate 116 passes the crank angle sensor 115.
At the time point E, the projection “2” of the crank angle sensor plate 116 passes through the crank angle sensor 115 due to normal rotation, and the output signal of the crank angle sensor 115 is inverted from High to Low. During forward rotation, the falling edge becomes the effective edge.
At time F, the protrusion “3” of the crank angle sensor plate approaches, so that the output signal of the crank angle sensor 115 is inverted from low to high.

FIG. 6 is a case where the crank angle identified by the ECU 119 deviates from the correct timing when turning from reverse rotation to normal rotation.
From time A to time D is the same as FIG.
At time E, the output signal of the crank angle sensor 115 is reversed from High to Low by approaching the protrusion “1” of the crank angle sensor plate 116.
At time point F, the output signal of the crank angle sensor 115 is inverted from low to high by moving away from the protrusion “1” of the crank angle sensor plate 116.
At time G, the center of the protrusion “2” of the crank angle sensor plate 116 passes through the crank angle sensor 115 by normal rotation, and the output signal of the crank angle sensor 115 is inverted from High to Low. During forward rotation, the falling edge becomes the effective edge.
At the time point H, the projection “3” of the crank angle sensor plate 116 approaches, and the output signal of the crank angle sensor 115 is inverted from Low to High.
Although time F is originally an invalid edge, it rises from a state where the low level is high (2.5 v), so it is determined as a valid edge, and an erroneous count of the crank angle sensor signal occurs.

As described above, the forward rotation and the reverse rotation can be distinguished by using the crank angle sensors having different low level output voltages at the time of forward rotation and reverse rotation.
Further, depending on the position from normal rotation to reverse rotation and from reverse rotation to normal rotation, missing detection of the crank angle sensor signal and erroneous detection may occur.
There is also a crank angle sensor that generates signals with different High level or Low level widths during normal rotation and reverse rotation. Even in this sensor specification, depending on the position from normal rotation to reverse rotation and reverse rotation to normal rotation, An erroneous detection of the sensor signal occurs.

FIGS. 7 to 17 are flowcharts for explaining the present embodiment, and show an execution procedure of a program executed by the microcomputer built in ECU 119.
This is a processing content for a crank angle sensor (SGT) signal and a cam angle sensor (SGC) signal for the three-cylinder engine shown in FIG.
FIG. 7 is a flowchart showing a process that is executed first when an ignition switch (not shown) is turned on by the driver and power is supplied to the ECU 119.
In step S701, the crank counter is set to 255.
The crank counter is a counter that is counted each time a signal from the crank angle sensor 115 is input, and the operation will be described later.
In step S702, the missing tooth crank counter is set to zero.
The missing tooth crank counter is a counter that counts the number of detected crank angle sensors between missing teeth in the crank angle sensor signal.
In step S703, the missing tooth detection count is set to zero. The number of missing teeth is the number of missing teeth detected. Although it is a 1-byte counter, if it is counted up to the maximum (255), it is held at 255.
In step S704, the injection number counter is set to zero.
The injection number counter is a counter that counts the number of times fuel injection has been performed after the start of the internal combustion engine. Although it is a 1-byte counter, if it is counted up to the maximum (255), it is held at 255.

FIG. 8 is a flowchart showing processing executed for each falling edge of the output signal of the crank angle sensor 115.
In step S801, it is determined whether the voltage value after falling of the crank angle sensor output signal is smaller than 1.25v. Since the low level of the crank angle sensor output signal is 0 v during forward rotation and 2.5 v during reverse rotation, 1.25 v is set as a threshold value for determining whether forward rotation or reverse rotation.
If the low level of the crank angle sensor output signal is 1.25 v or higher, it is determined in step S803 that the rotation is not normal, and this process is terminated.
If the low level of the crank angle sensor output signal is less than 1.25v, it is determined in step S802 that the rotation is normal.
If it is determined in step S804 that the engine speed is 500 r / m or more, it is determined in step S806 that the normal mode is set. If it is smaller than 500 r / m, it is determined in step S805 that the engine is in the start mode.
The engine rotation is calculated from the time interval for each B75 timing of the simulated crank angle signal (see FIG. 18 described later) generated from the crank angle sensor signal. Until the B75 timing is twice, the engine speed is set to 0 r / min.
In step S807, missing tooth detection and crank counter identification processing are performed, and in step S808, the crank counter is counted up.
Missing tooth detection, crank counter identification processing, and crank counter count-up will be described later.

FIG. 9 is a flowchart illustrating processing executed for each rising edge of the crank angle sensor 115.
In step S901, it is determined whether the voltage value before rising of the crank angle sensor output signal is 1.25 v or more.
If the voltage value before the rise of the crank angle sensor output signal is less than 1.25 v, it is determined in step S903 that the reverse rotation is not reverse, and this process is terminated.
If the voltage value before the rise of the crank angle sensor output signal is 1.25 v or more, it is determined in step S902 that the rotation is reverse.
In step S904, the crank counter is counted down. The processing contents will be described later.

FIG. 10 is a flowchart showing the processing content of “missing tooth detection and crank counter value specification” in step S807 of FIG. 8 described above.
In step S1001, 1 is added to the missing tooth crank counter. The missing tooth crank counter counts the number of crank angle sensor detection signals between missing teeth, is used for cylinder identification, and is cleared every time missing teeth are detected.
In step S1002, it is determined whether the missing tooth crank counter is 5 or more. If it is less than 5, this process is exited. Since the missing tooth detection is performed using the time between three consecutive crank angle sensor signals, it cannot be performed correctly unless the crank angle sensor signal is detected at least four times. Therefore, the missing tooth detection process is performed only when the missing tooth crank counter is 5 or more.
If the missing tooth crank counter is 5 or more in step S1002, the crank angle sensor signal cycle ratio (ΔT) is calculated in step S1003.
The crank angle sensor signal cycle ratio (ΔT) is expressed by the following formula 1.
ΔT = [{T (n−1) / T (n)} + {T (n−1) / T (n−2)}] / 2
... Formula 1
here,
ΔT: Crank angle sensor signal cycle ratio T (n): Crank angle sensor signal cycle (current)
T (n-1): Crank angle sensor signal cycle (previous)
T (n-2): Crank angle sensor signal cycle (previous times)

The missing tooth has two missing teeth, the angle between the crank angle sensors at the missing tooth portion is 30 deg CA, and the angle between the crank angle sensors at the non-missing tooth portion is 10 deg CA.
Note that “CA” is an abbreviation of “Crank Angle”.
When the missing tooth has two missing teeth, the portion of the crank angle sensor plate formed every 10 deg CA is missing only two specific portions, and this missing tooth portion has a crank angle sensor signal interval. 30 deg CA. In the SGT of FIG. 18 to be described later, a broken tooth portion is indicated by a broken line.
In the crank angle sensor signal next to the missing tooth (the positions of crank counters 65, 17, 29, and 53 in FIG. 18 to be described later), ΔT is a value around 3. The reason why ΔT does not become exactly 3 is that there is a period variation. Other than the crank angle sensor signal next to the missing tooth, ΔT is about 1 or less than 1.

If ΔT is less than 2 in step S1004, it is determined that there is no missing tooth, and the process is left as it is.
Since ΔT for missing teeth is about 3 and ΔT for other than missing teeth is about 1 or less than 1, the threshold value is 2.
If ΔT is 2 or more in step S1004, 1 is added to the number of missing teeth detection in step S1005. The number of missing teeth detection is defined by a 1-byte size, expressed as 0 to 255, and when 255 is reached, the value is held.
In step S1006, it is determined whether the number of missing teeth detection is one. If it is once, it is determined in step S1007 whether the crank counter is 255 times.
If it is determined in step S1007 that the crank counter is not 255, crank counter value correction processing is performed in step S1008. Details will be described later.
The crank counter is set to 255 at the time of initialization processing for starting the ECU 119 (step S701 in FIG. 7), and is 255 when the cylinder discrimination is not completed. After cylinder discrimination is completed, it is counted every time a crank angle sensor signal is input.
If it is determined in step S1006 that the number of missing teeth detection is not one, it is determined that the number of missing teeth detection is two or more, and crank counter value specifying processing is performed in step S1009. Details will be described later.
In step S1010, the missing tooth crank counter is cleared to zero.
In step S1011, the cam angle counter is cleared to zero.

FIG. 11 is a flowchart showing the processing content of “count up of crank counter” in step S808 of FIG. 8 described above.
In step S1101, it is determined whether the crank counter is not 255.
If the crank counter is not 255, it is determined in step S1102 whether the crank counter is 71 (see FIG. 18 described later). In the case of 71, the crank counter is set to 0 in step S1106.
The crank counter counts a signal of every 10 deg CA of the crank angle sensor signal between crank angles 720 deg CA (2 rotations), and counts between 0 and 71. When it reaches 71, it returns to 0.
If it is determined in step S1102 that the crank counter is not 71, it is determined in step S1103 whether the crank counter is 13, 25, 49, or 61.
If the crank counter corresponds to these, 3 is added to the crank counter in step S1105. Next to the crank counter of 13, 25, 49 or 61 is a missing tooth portion, and the interval between the crank angle sensor signals is 30 degCA, so 3 is added.
If No in step S1103, the crank counter adds 1 in step S1104.

FIG. 12 is a flowchart showing the count-down process of the crank counter in step S904 in FIG.
In step S1201, it is determined whether the crank counter is not 255. If not 255, it is determined in step S1202 whether or not the stop mode is set.
In the stop mode, the engine is stopped in the reverse rotation state, and the crank counter is not counted down because it is an invalid edge in the normal rotation by the starter at the start of engine rotation. The stop mode determination will be described later.
In step S1203, it is determined whether the crank counter is not zero. In the case of 0, the crank counter is set to 71 in step S1207.
The crank counter counts a signal at every 10 deg CA of the crank angle sensor signal during a crank angle of 720 deg CA (2 rotations), and counts between 0 and 71. Next, after reaching 0 in reverse, set to 71.
If it is determined in step S1203 that the crank counter is not 0, it is determined in step S1204 whether the crank counter is 16, 28, 52, or 64.
If the crank counter corresponds to these, 3 is subtracted from the crank counter in step S1206. Before the crank counter is 16, 28, 52 or 64, there is a missing tooth portion, and since the crank angle sensor signal is 30 deg CA, 3 is subtracted.
If No in step S1204, the crank counter decrements by 1 in step S1205.

FIG. 13 is a flowchart showing an interrupt process executed at every falling edge of the cam angle sensor signal (SGC).
In step S1301, 1 is added to the cam angle counter.

FIG. 14 is a flowchart showing the crank counter value specifying process in step S1009 of FIG.
In step S1401, it is determined whether the missing tooth crank counter is 22 and the cam angle counter is 2. If yes, the crank counter is set to 17 in step S1402.
If No in step S1401, it is determined in step S1403 whether the missing tooth crank counter is 10 and the cam angle counter is 0. If yes, the crank counter is set to 29 in step S1404.
If No in step S1403, it is determined in step S1405 whether the missing tooth crank counter is 22 and the cam angle counter is 1. If yes, the crank counter is set to 53 in step S1406.
If NO in step S1405, it is determined in step S1407 whether the missing tooth crank counter is 10 and the cam angle counter is 1. If yes, the crank counter is set to 65 in step S1408.
If No in step S1407, 255 is set in the crank counter in step S1409.
In this case, since the values of the crank counter and cam angle counter between the missing teeth do not correspond to any of the design values, it is determined that the crank counter cannot be correctly counted, and an initial state in which the crank counter cannot be specified is set.

FIG. 15 is a flowchart showing the crank counter value correction processing in step S1008 of FIG.
In step S1501, it is determined whether the missing tooth crank counter is 22, the cam angle counter is 2, and the crank counter is 16 or more and 18 or less.
If yes, the crank counter is set to 17 in step S1502.
If NO in step S1501, it is determined in step S1503 whether the missing tooth crank counter is 10, the cam angle counter is 0, and the crank counter is 28 or more and 30 or less. If yes, the crank counter is set to 29 in step S1504.
If NO in step S1503, it is determined in step S1505 whether the missing tooth crank counter is 22, the cam angle counter is 1, and the crank counter is 52 or greater and 54 or less. If yes, the crank counter is set to 53 in step S1506.
If NO in step S1505, it is determined in step S1507 whether the missing tooth crank counter is 10, the cam angle counter is 1, and the crank counter is 64 or more and 66 or less. If yes, the crank counter is set to 65 in step S1508.
If No in step S1507, 255 is set in the crank counter in step S1509.
In this case, since the values of the crank counter and cam angle counter between the missing teeth do not correspond to any of the design values, it is determined that the crank counter cannot be correctly counted, and an initial state in which the crank counter cannot be specified is set.
These are correct when the crank counter deviates in the range of ± 1 from the correct value when the number of missing teeth detection is one.

FIG. 16 is a flowchart showing stop mode determination processing. This process is executed every predetermined time.
If it is determined in step S1601 that the crank angle sensor signal has not been input for 0.2 sec or longer, the stop mode is determined in step S1602.
In step S1603, the missing tooth crank counter is cleared to zero. In step S1604, the number of missing teeth detection is cleared to zero. In step S1605, the fuel injection number counter is cleared to zero.

FIG. 17 is a flowchart showing a fuel injection process at the time of start-up and executed at every falling edge of the crank angle sensor signal.
In step S1701, it is determined whether the start mode is set. If it is not in the start mode, the process exits without doing anything.
If it is the start mode in step S1701, it is determined in step S1702 whether the initial injection is being performed. Specifically, if the injection number counter is 0, it is determined that the first injection is being performed.
If it is the first injection (injection number counter = 0), it is determined in step S1703 whether the crank counter is 20, and if it is 20, the injection is made into three cylinders in step S1704, and the injection number counter is determined in step S1705. Add 1 to.
In step S1706, it is determined whether the crank counter is 44. If it is 44, the cylinder is injected into two cylinders in step S1707, and 1 is added to the injection number counter in step S1708.
In step S1709, it is determined whether the crank counter is 68. If it is 68, injection is performed to one cylinder in step S1710, and 1 is added to the injection number counter in step S1711.
The stop of the injection is stopped when an injection time set in advance according to the water temperature has elapsed.

If it is determined in step S1702 that the injection is not the first injection (injection number counter ≧ 1), it is determined in step S1712 whether the crank counter is 17, and if it is 17, the injection is performed to the three cylinders in step S1713. In S1714, 1 is added to the injection number counter.
In step S1715, it is determined whether the crank counter is 41. If it is 41, the cylinder is injected into step 2 in step S1716, and 1 is added to the injection number counter in step S1717.
In step S1718, it is determined whether or not the crank counter is 65. If 65, the fuel is injected into one cylinder in step S1719, and 1 is added to the injection number counter in step S1720.
The stop of the injection is stopped when an injection time set in advance according to the water temperature has elapsed.
The injection number counter is cleared to 0 when the stop mode of FIG. 16 is established, and is incremented by 1 every time fuel is injected. The injection number counter uses a 1-byte counter, and when it reaches the maximum value of 255, it is not added any more and remains at 255.

FIG. 18 is a timing chart showing the operation of the internal combustion engine fuel injection control apparatus according to the present embodiment.
The simulated crank angle signal is a simulated signal formed by processing in the ECU from the crank angle sensor signal (SGT) and the cam angle sensor signal (SGC), and BTDC 75 degCA of each cylinder (time points A, D, G in FIG. 18). ) And rise at BTDC 5 degCA (time points B, E, and H in FIG. 18).
# 1 to # 3INJ are injection drive signals to the injector 106, and the fuel is being injected while it is at the high level. # 1 to # 3SPK are energization signals to the ignition coil 111. The energization of the ignition coil is started at the rising edge and the energization to the ignition coil is interrupted at the falling edge, whereby a spark is induced in the ignition plug 112. .
# 1 to # 3 strokes indicate the strokes of each cylinder.
SGC indicates a cam angle sensor signal, and SGT indicates a crank angle sensor signal. The crank counter is a value of the crank counter recognized by the ECU.

During the process from when the engine is operating due to the stop of the injector, the compression of the air in the cylinder during the compression stroke becomes a resistance and stops halfway to the compression top dead center or rotates to near the compression top dead center After that, the piston is pushed back in the reverse rotation direction by the compression pressure and stopped. These may be repeated several times.
There are various processes leading to the engine stop, such as “stop with normal rotation” or “stop with reverse rotation from normal rotation”, but the stop position is approximately near the same simulated crank angle B75.
When the stop position is on the retard side (right side in the figure) from the time point A in FIG. 18 and on the advance side (left side in the figure) from the time point J, if the injection start timing is the time point J, # 1 cylinder Therefore, the fuel-air mixture in the cylinder is combusted by ignition of the # 1 cylinder at the time point E, and the engine can be started.
If the initial fuel injection timing at time point J is too retarded, an appropriate amount of fuel will be mixed into the cylinder during the intake stroke and will not be sucked into the cylinder. It is necessary to decide.
At the second and subsequent time points D and G, the fuel can be injected without delaying the fuel injection timing. Therefore, the fuel is injected at the normal start-up injection timing.

FIG. 19 is a timing chart showing the operation of the fuel injection control device for the internal combustion engine when the initial fuel injection timing is not retarded.
When the engine stops at the retarded angle side from the time point A, fuel injection at the time point A cannot be performed. Therefore, at the ignition timing at the time point E, the air-fuel mixture necessary for combustion is not in the cylinder and does not burn. The engine is started when the fuel injection at the time point D is combusted by the ignition at the time point H. In this case, starting of one stroke is delayed with respect to FIG.

In this embodiment, as shown in FIG. 17, it is determined in step S1702 whether or not the first injection after the start of the start, and if it is the first injection, the processing from step S1703 to step S1711 is performed and the second and subsequent injections are performed. If so, the processing from step S1712 to step S1720 is performed.
In the case of the first injection, by delaying the injection timing from the second and subsequent fuel injections, the engine stop position is advanced from the initial injection timing and from the second and subsequent fuel injection timings to the retarded side. In some cases, the fuel injection of the cylinder in the intake stroke can be performed immediately after the start of the start, so that the start is advanced by one stroke and the start time can be advanced.
In addition, since fuel injection is performed after the overlap of the intake valve and the exhaust valve at the time point K in FIG. 18 (the state where the intake valve and the exhaust valve are open at the same time), unburned gas does not blow through the exhaust pipe, and the engine starts. Exhaust gas deterioration at the time can be prevented.

Further, in the present embodiment, as shown in FIGS. 3 to 6, the crank angle sensor having different output signals at the time of forward rotation and reverse rotation is used to identify whether it is in the forward rotation state or the reverse rotation state. In addition, by determining the stop position, the cylinder position can be determined from the initial stage at the time of restart.
As a result, fuel can be injected into the cylinders in the intake stroke immediately after the start of the start, and the start can be accelerated and the stop position can be determined without adding a new sensor or the like, resulting in an increase in cost. Is feasible.

Further, in the present embodiment, as shown in FIGS. 10 and 15, when the missing tooth is detected once in step S1006, the crank counter is not 255, that is, if the crank angle can be specified, The process proceeds to the process of FIG. If the crank counter deviates from the correct crank angle, which is the missing tooth detection timing, within a predetermined crank angle range, the crank counter is corrected to the correct crank angle.
For this reason, even when the crank angle is incorrectly identified, it is possible to improve the starting failure due to the ignition timing shift.
Since missing teeth are always present before ignition for the first fuel injection, the crank angle can be corrected by the ignition timing, and ignition at the correct ignition timing is always possible.

Further, in this embodiment, when the crank angle sensor signal from the stop state rises from a state where the low level is high, it is determined that it is an invalid edge, and as shown in step S1202 of FIG. If there is, the count error at the start of the start of the crank position can be prevented by not performing the minus count of the crank counter after step 1203, that is, the reverse count.
As a result, fuel injection can be performed at the correct timing, and deterioration of startability due to deterioration of intake of the air-fuel mixture into the cylinder due to a shift in injection timing can be prevented.

  As described above, the fuel injection control device for the internal combustion engine according to the present embodiment includes the crank angle detection unit 201 that detects the crank angle of the internal combustion engine 101, and the cam angle detection unit 202 that detects the cam angle of the internal combustion engine. The stop position detection / storage means 203 detects and stores the stop position of the internal combustion engine based on the crank angle detected by the crank angle detection means 201, and the internal combustion engine 101 based on the crank angle detected by the crank angle detection means 201. A crank for identifying the crank position of the internal combustion engine 101 based on the start determination means 204 for determining start from the stop position of the engine, the crank angle detected by the crank angle detection means 201 and the cam angle detected by the cam angle detection means 202 Based on the specification result of the position specifying means 205 and the crank position specifying means 205, the internal combustion engine 101 is started for the second time and after the start. The first injection timing calculating means 206 for calculating (calculating) the fuel injection timing of the first engine and the first fuel injection timing after starting the internal combustion engine 101 based on the specified result of the crank position specifying means 205 are calculated (calculated). Based on the second injection timing calculation means 207 later than the injection timing of 1 and the stop position of the internal combustion engine 101 stored in the stop position detection / storage means 203 and the determination result of the start determination means 204, the first injection The fuel injection timing selection means 208 for selecting either of the injection timings calculated (calculated) by the timing calculation means 206 or the second injection timing calculation means 207, and the fuel injection timing selected by the fuel injection timing selection means 208 Fuel injection means 209 for performing injection is provided.

Further, in the fuel injection control device for an internal combustion engine according to the present embodiment, the initial fuel injection after the start of the start is at the retard side of the start start position from the first injection timing, and from the second injection timing. Is also on the advance side, the first fuel injection after the start of the start is performed at the detection timing of the crank angle detecting means 201 detected at the start of the start, and the start start position is advanced from the first injection timing. If it is, the fuel injection is performed at the first fuel injection timing, and after the first fuel injection, the fuel injection is performed at the first fuel injection timing.
Further, the crank angle detection means 201 of the fuel injection control device for the internal combustion engine according to the present embodiment outputs a crank angle signal corresponding to the forward rotation and the reverse rotation of the internal combustion engine 101, and stops position detection / storage means. 203 detects and stores the stop position of the internal combustion engine 101 by counting the respective crank angle signals during forward rotation and reverse rotation.

The fuel injection control device for an internal combustion engine according to the present embodiment includes specific crank angle identifying means for identifying a specific crank angle, and after the start of the internal combustion engine 101, the specific crank angle identifying means performs the specific crank angle identifying means. If the crank angle counted from the stop position stored in the stop position detection / storage means 203 after the start of the engine is different from the crank angle detected by the crank angle detection means 201, the crank angle detection means 201 The crank angle detected in step 1 is set as the current crank angle.
Further, the stop position detection / storage means 203 of the internal combustion engine fuel injection control apparatus according to the present embodiment does not count the reverse crank angle when the internal combustion engine 101 is started.

Embodiment 2. FIG.
FIG. 20 is an improvement of the above-described first embodiment. Specifically, the “fuel injection process at start-up” in the first embodiment shown in FIG. 17 is improved.
20, steps that are different from those in FIG. 17 are steps S2003, S2006, and S2009.
The processes in other steps in FIG. 20 are the same as the processes in the corresponding steps in FIG.
That is, the processes in step S2001, step S2002, step S2004, step S2005, step S2007, step S2008, step S2010 to step S2020 in FIG. 20 are the same as step S1701, step S1702, step S1704, step S1705, step S1705 in FIG. This is the same as the processing in S1707, S1708, S1710 to S1720.

Here, referring to the first embodiment for portions of the same processing, only a portion where processing is different (that is, processing steps where processing is different) will be described.
In step S2003, whether or not the crank counter is 17 or more and 20 or less and fuel injection has not yet started is determined based on whether or not the injection number counter is zero. If the condition is satisfied, the fuel is injected into the third cylinder in step S2004.
In step S2006, whether or not the crank counter is 41 or more and 44 or less and the fuel injection has not yet started is determined based on whether or not the injection number counter is zero. If the condition is met, inject into 2 cylinders in 2007.
In step S2009, whether or not the crank counter is 65 or more and 68 or less and fuel injection has not yet started is determined based on whether or not the injection number counter is zero. If the condition is satisfied, the fuel is injected into one cylinder in step S2010.

As described above, in the present embodiment, when the crank counter is within the predetermined range and fuel injection has not yet started, the fuel can be injected by injecting fuel into the corresponding cylinder. Within the angular range, fuel injection can be started at the most advanced position.
Thus, by performing fuel injection at the most advanced position within a possible range while minimizing the retardation of the fuel injection timing, it becomes possible to promote atomization and prevent deterioration of startability.

  As described above, the fuel injection control device for an internal combustion engine according to the present embodiment counts the crank counter when the count value of the crank counter is within a predetermined range and fuel injection has not started yet. Fuel is injected into the cylinder corresponding to the value.

Embodiment 3 FIG.
FIG. 21 shows an improvement of the above-described first embodiment. Specifically, the “fuel injection process at start-up” in the first embodiment shown in FIG. 17 is further improved.
In FIG. 21, steps that are different from those in FIG. 17 are steps S2103, S2106, and S2109.
The processes at other steps in FIG. 21 are the same as the processes at the corresponding steps in FIG.
That is, the processing in step S2101, step S2102, step S2104, step S2105, step S2107, step S2108, step S2110, and step S2120 in FIG. This is the same as the processing in S1707, S1708, S1710 to S1720.

Here, referring to the first embodiment for portions of the same processing, only a portion where processing is different (that is, processing steps where processing is different) will be described.
In step S2103, it is determined whether the crank counter is at the retard side injection start timing T1. If the condition is satisfied, the fuel is injected into the third cylinder in step S2104.
In step S2106, it is determined whether the crank counter is at the retard side injection start timing T2. If the condition is satisfied, the fuel is injected into the second cylinder in step S2107.
In step S2109, it is determined whether the crank counter is at the retard side injection start timing T3. If the condition is satisfied, the fuel is injected into one cylinder in step S2110.

22 to 24 are set values of the retard side injection start timing (T1, T2, T3) to be compared with the value of the crank counter in step S2103, step S2106, and step S2109 in FIG.
FIG. 22 shows the set value of the retard side injection start timing T1, FIG. 23 shows the set value of the retard side injection start timing T2, and FIG. 24 shows the set value of the retard side injection start timing T3.
Each of T1, T2, and T3 is set to a value corresponding to the coolant temperature for engine cooling, and is stored as a map in the ROM in the ECU, and the value corresponding to the coolant temperature is referred to. .
The reason for changing the retard side injection start timing according to the cooling water temperature is that the fuel injection amount is larger as the water temperature is lower, that is, the fuel injection amount is longer as the water temperature is lower, that is, the injector valve opening period is longer. If the injection start timing is delayed, the fuel injected in the intake stroke does not completely enter the cylinder, causing a start failure.
Therefore, as the fuel injection amount increases and the injector driving time is longer on the low water temperature side, the retarded side injection start timing is set to the advanced angle side than the high water temperature side.
In addition, if the set values of T1, T2, and T3 are made to be a difference map with respect to the reference (second and subsequent injection timings 17, 41, and 65), a single map can be used.

FIG. 25 is an improvement of the above-described first embodiment. Specifically, the “fuel injection process at start-up” in the first embodiment shown in FIG. 17 is further improved.
In FIG. 25, steps that are different from those in FIG. 17 are steps S2503, S2506, and S2509.
The processing in other steps in FIG. 25 is the same as the processing in corresponding steps in FIG.
That is, the processes in Step S2501, Step S2502, Step S2504, Step S2505, Step S2507, Step S2508, Step S2510, and Step S2520 in FIG. This is the same as the processing in S1707, S1708, S1710 to S1720.

Here, referring to the first embodiment for portions of the same processing, only a portion where processing is different (that is, processing steps where processing is different) will be described.
In step S2503, whether or not the crank counter is 17 or more and T1 or less and fuel injection has not been started is determined based on whether or not the injection number counter is zero. If the condition is satisfied, the fuel is injected into the third cylinder in step S2504.
In step S2506, whether or not the crank counter is 41 or more and T2 or less and fuel injection has not yet started is determined based on whether or not the injection number counter is zero. If the condition is satisfied, the fuel is injected into the second cylinder in step S2507.
In step S2509, whether or not the crank counter is 65 or more and T3 or less and fuel injection has not yet started is determined based on whether or not the injection number counter is zero. If the condition is satisfied, the fuel is injected into one cylinder in step S2510.

The retard side injection start timing (T1, T2, T3) is referred to from the set value corresponding to the coolant temperature of the engine cooling coolant shown in FIGS.
Thus, by setting the timing of the initial fuel injection according to the water temperature, even if the injector drive period becomes longer due to the increase in the fuel injection amount at low water temperature, the fuel can be sucked into the cylinder during the intake stroke. It becomes possible to finish fuel injection, and fuel fails to be sucked into the cylinder, causing a start-up failure, or fuel that could not be sucked in blows out to the exhaust side at the next overlap, resulting in worsening of exhaust gas at start-up Can be prevented.

  As described above, in the fuel injection control device for an internal combustion engine according to the present embodiment, the second injection timing is changed according to the temperature of the internal combustion engine.

  INDUSTRIAL APPLICABILITY The present invention is useful for realizing a fuel injection control device for an internal combustion engine that can improve startability of the internal combustion engine and prevent deterioration of exhaust gas at the time of start.

DESCRIPTION OF SYMBOLS 101 Internal combustion engine 102 Air cleaner 103 Intake pipe 104 Throttle valve 105 Pressure sensor 106 Injector 107 Exhaust pipe 108 Front O2 sensor 109 Rear O2 sensor 110 Three-way catalyst 111 Ignition coil 112 Ignition plug 113 Cam angle sensor 114 Cam angle sensor plate 115 Crank angle sensor 116 Crank angle sensor plate 117 Cooling water 118 Water temperature sensor 119 Control unit (ECU)
201 Crank angle detection means 202 Cam angle detection means 203 Stop position detection / storage means 204 Start determination means 205 Crank position specification means 206 First injection timing calculation means 207 Second injection timing calculation means 208 Fuel injection timing selection means 209 Fuel Injection means

In the fuel injection control device for an internal combustion engine according to the present invention, crank angle detection means for detecting a crank angle of the internal combustion engine, cam angle detection means for detecting the cam angle of the internal combustion engine, and the crank angle detection means detect the crank angle detection means. Stop position detection / storage means for detecting and storing the stop position of the internal combustion engine based on the crank angle, and determining start of the internal combustion engine from the stop position based on the crank angle detected by the crank angle detection means Starting determination means, crank position specifying means for specifying a crank position of the internal combustion engine based on a crank angle detected by the crank angle detecting means and a cam angle detected by the cam angle detecting means, and the crank position specifying a first injection timing calculation means for calculating a first injection timing of the internal combustion engine based on a particular result of means, the crank localization A second injection timing calculation means for calculating a second injection timing slower than the first injection timing of the internal combustion engine in inhalable range into the cylinder on the basis of the identification result of step, the stop position detection The second injection timing is selected for the first injection based on the stop position of the internal combustion engine stored in the storage means and the determination result of the start determination means, and the first injection is performed for the second and subsequent injections. and the fuel injection timing selecting means for selecting the injection timing, in which a fuel injection means for performing fuel injection by the fuel injection timing fuel injection timing selection means has selected.

Claims (7)

  Crank angle detection means for detecting the crank angle of the internal combustion engine, cam angle detection means for detecting the cam angle of the internal combustion engine, and detecting the stop position of the internal combustion engine based on the crank angle detected by the crank angle detection means A stop position detection / storage means for storing the start position, a start determination means for determining start of the internal combustion engine from the stop position based on a crank angle detected by the crank angle detection means, and a detection by the crank angle detection means Crank position specifying means for specifying the crank position of the internal combustion engine based on the crank angle to be detected and the cam angle detected by the cam angle detection means, and starting of the internal combustion engine based on the specification result of the crank position specifying means Based on the first injection timing calculating means for calculating the fuel injection timing for the second and subsequent times, and the result of specifying the crank position specifying means The second injection timing calculation means that is later than the first injection timing for calculating the first fuel injection timing after the start of the internal combustion engine, the stop position of the internal combustion engine stored in the stop position detection / storage means, and Fuel injection timing selection means for selecting either one of the injection timings calculated by the first injection timing calculation means or the second injection timing calculation means based on the determination result of the start determination means; and the fuel injection timing selection A fuel injection control device for an internal combustion engine, comprising: fuel injection means for injecting fuel at a fuel injection timing selected by the means.   In the first fuel injection after the start of the start, when the start start position is on the retard side with respect to the first injection timing and on the advance side with respect to the second injection timing, the start of the start of the start is started. The first fuel injection after the start of the start is performed at the detection timing of the crank angle detecting means detected at the time, and when the start start position is on the advance side of the first injection timing, the first fuel injection timing is The fuel injection control device for an internal combustion engine according to claim 1, wherein fuel injection is performed, and fuel injection is performed at the first fuel injection timing after the first fuel injection. The crank angle detection means outputs a crank angle signal corresponding to each of the forward rotation and reverse rotation of the internal combustion engine,
The stop position detecting / storing means detects and stores the stop position of the internal combustion engine by counting the crank angle signals at the time of forward rotation and reverse rotation, respectively. A fuel injection control device for an internal combustion engine as described.   Specific crank angle identifying means for identifying a specific crank angle, and after the start of the internal combustion engine, when the specific crank angle is identified by the specific crank angle identifying means, the stop position detection / storage after the start of the start When the crank angle counted from the stop position stored in the means and the crank angle detected by the crank angle detection means are different, the crank angle detected by the crank angle detection means is set as the current crank angle. The control apparatus for an internal combustion engine according to claim 3.   4. The control apparatus for an internal combustion engine according to claim 3, wherein the stop position detection / storage means does not count a reverse crank angle when the internal combustion engine is started.   A crank counter that counts the crank angle, and if the count value of the crank counter is within a predetermined range and fuel injection has not yet started, fuel is supplied to the cylinder corresponding to the count value of the crank counter. The fuel injection control device for an internal combustion engine according to claim 1 or 2, wherein injection is performed.   The fuel injection control device for an internal combustion engine according to claim 1 or 2, wherein the second injection timing is changed according to a temperature of the internal combustion engine.

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