JP2740715B2 - Internal combustion engine control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine control device, and more particularly to an internal combustion engine control device capable of preventing a malfunction caused by starter noise generated at the time of cranking of an engine having a plurality of cylinders and realizing a good engine start. .

[0002]

2. Description of the Related Art In a magnetic pickup type crank angle sensor for magnetically detecting an engine speed or a specific crank angle, the output is determined by the magnitude of a change in magnetic flux density across a coil. For this reason, at the time of starting that requires a large amount of current to rotate the starter, this current flows through the magnetic material near the sensor, causing a change in magnetic flux. There is a problem that the engine control malfunctions.

In order to solve such a problem, Japanese Patent Laid-Open Publication No.
In the prior art described in Japanese Patent Application Laid-Open No. 0-62666, a timer is provided to stop the function of the ignition unit in synchronization with the operation of the electromagnetic switch of the starter and to return the function of the ignition unit after the start-up of the starter rush current is completed. The output of the ignition signal is stopped for a certain period immediately after the starter signal is input.

In the prior art described in Japanese Patent Application Laid-Open No. 60-108568, the signal is set by a signal from a rotation detector or a signal from a waveform processing circuit thereof, and is reset by an output signal immediately after being arbitrarily set. , A flip-flop configured so as not to be set by a subsequent signal is provided so that the ignition coil is not energized at least during a period from the first set to the reset.

On the other hand, in an internal combustion engine equipped with an engine having a plurality of cylinders, as described in, for example, Japanese Patent Application Laid-Open No. Sho 62-26167, the ignition cylinder is determined based on a signal from a rotation detector, and the cylinder is ignited. 2. Description of the Related Art An internal combustion engine control device including an electronic distribution circuit that electronically distributes a signal is known.

[0006]

SUMMARY OF THE INVENTION Japanese Patent Application Laid-Open No. 60-6266
The prior art described in Japanese Patent Application Laid-Open No. 6-108568 and Japanese Patent Application Laid-Open No. 60-108568 prevents erroneous ignition due to noise generated when the engine is started. However, none of the prior arts merely output an ignition signal.
No consideration is given to a control device having an electronic power distribution as described in 1 6 73 JP. That is, in the control device including the electronic power distribution circuit, once a cylinder is erroneously determined by noise generated at the time of starting the engine, the ignition signal output thereafter is distributed to the incorrect cylinder and ignited. . In order to prevent erroneous ignition by applying the above-mentioned prior art device to a control device provided with an electronic distribution circuit, the number of ignition units and timers (Japanese Patent Laid-Open No. 60-62666) or waveform processing circuits and flip-flops is determined by the number of cylinders. (Japanese Patent Application Laid-Open No. Sho 60-108568), which is difficult to realize because the configuration is complicated and expensive.

Further, in the above prior art, misfire is considered, but misfuel injection is not considered.
In a device that controls fuel injection as well as electronic power distribution, erroneous fuel injection occurs due to the noise at the time of starting.

A first object of the present invention is to provide an internal combustion engine control device having a cylinder discriminating function, which can prevent erroneous ignition with a simple configuration and has high practicality.

A second object of the present invention is to provide an internal combustion engine control device having a cylinder discriminating function which has a simple configuration and prevents erroneous ignition and erroneous fuel injection.

[0010]

In order to achieve the first object, the present invention provides an engine having a plurality of cylinders, rotation detecting means for detecting rotation of the engine, and a signal from the rotation detecting means. A cylinder discriminating circuit for discriminating a cylinder based on the signal, a means for calculating an ignition timing based on a signal from the rotation detecting means, and an ignition signal corresponding to the ignition timing based on a signal from the cylinder discriminating circuit in the order of ignition. An internal combustion engine control device provided with first distribution means for distributing to the cylinders, comprising: a cylinder determination stop means for stopping the operation of the cylinder determination circuit for a predetermined period immediately after the start signal of the engine is input; The distribution of the ignition signal by the first distribution means is stopped by stopping the operation of the cylinder discriminating circuit.

According to another aspect of the present invention, there is provided an internal combustion engine control apparatus, comprising: means for calculating a fuel injection amount based on a signal from the rotation detecting means; and a cylinder discriminating circuit. Second distributing means for distributing a fuel injection signal corresponding to the fuel injection amount to the fuel injection device in the order of ignition based on the above signal, and the second distributing means during a period in which the operation of the cylinder discriminating circuit is stopped. And a fuel distribution stopping means for stopping the distribution of the fuel injection signal in the step (c).

In the above internal combustion engine control device, preferably, the cylinder discrimination stopping means stops the operation of the cylinder discrimination circuit for a preset time immediately after the input of the start signal. Alternatively, the cylinder discriminating stop means may stop the operation of the cylinder discriminating circuit immediately after the start signal is input until the signal from the rotation detecting means is generated a preset number of times.

[0013] The internal combustion engine control device preferably includes means for detecting a cooling water temperature of the engine, and the predetermined period is set by the cooling water temperature of the engine. Alternatively, the internal combustion engine control device may include means for detecting a battery voltage, and the predetermined period may be set by the battery voltage.

In the above internal combustion engine control device, preferably, the rotation detecting means includes a magnetic pickup type reference position detector for detecting that the piston position of the engine is at a predetermined position, and the reference position detector. And a first waveform shaping circuit for shaping the waveform of the reference position signal. The cylinder discrimination stop means stops the operation of the cylinder discrimination circuit by stopping the output of the first waveform shaping circuit.

Alternatively, the rotation detecting means includes a magnetic pickup type cylinder discriminating detector for detecting a cylinder discriminating signal for performing a cylinder discriminating operation, and a waveform shaping means for shaping the cylinder discriminating signal from the cylinder discriminating detector. And the cylinder discriminating stop means may stop the operation of the cylinder discriminating circuit by stopping the output of the second waveform shaping circuit.

Further, the rotation detecting means includes a magnetic pickup type angle detector for detecting a rotation angle of an engine crankshaft, and a third waveform shaping circuit for waveform shaping an angle signal from the angle detector. In addition, the cylinder discrimination stopping means may stop the operation of the cylinder discrimination circuit by stopping the output of the third waveform shaping circuit.

The rotation detecting means includes a magnetic pickup type reference position detector for detecting that the piston position of the engine is at a predetermined position, and a magnetic pickup type angle detecting unit for detecting the rotation angle of the engine crankshaft. And a reference angle generation circuit for generating a reference angle signal from a reference position signal and an angle signal from the reference position detector and the angle detector, and the cylinder discrimination stopping means outputs an output of the reference angle generation circuit. The operation of the cylinder determination circuit may be stopped by stopping the operation.

Preferably, the internal combustion engine control device further includes a power distribution stopping means for stopping the operation of the first distribution means for a predetermined period immediately after the input of the engine start signal. When the operation of the first distribution unit is stopped by the means and the operation of the cylinder determination circuit is stopped, the distribution of the ignition signal by the first distribution unit is stopped.

In order to achieve the first object, the present invention provides an engine having a plurality of cylinders, a magnetic pickup type rotation detector for detecting the rotation of the engine, and a signal from the rotation detector. A waveform shaping circuit for shaping the waveform, a cylinder determining circuit for determining a cylinder based on a signal from the waveform shaping circuit, a means for calculating an ignition timing based on a signal from the waveform shaping circuit, and a signal from the cylinder determining circuit. A distribution means for distributing an ignition signal corresponding to the ignition timing to the cylinders in the order of ignition based on the signal, wherein the waveform shaping circuit adjusts the voltage level of the signal from the rotation detector to a predetermined level. (Slice level)
Means for changing the level of the output signal when the signal exceeds the threshold, and means for increasing the predetermined level for a predetermined period immediately after the input of the engine start signal. Is stopped, the operation of the cylinder discrimination circuit is stopped, and the distribution of the ignition signal by the distribution means is stopped.

[0020]

[0021]

A cylinder discrimination stopping means for stopping the operation of the cylinder discriminating circuit for a predetermined period immediately after the input of the engine start signal is provided, and the distribution of the ignition signal is stopped by stopping the operation of the cylinder discriminating circuit. Thus, erroneous ignition is prevented during noise generation at the start with a simple configuration in which only the cylinder discrimination stop means is provided.

Also, during the period in which the operation of the cylinder discriminating circuit is stopped, the distribution of the fuel injection signal is also stopped, so that
In addition to erroneous ignition, erroneous fuel injection is also prevented.

Further, means for increasing the slice level of the waveform shaping circuit for a predetermined period is provided, and the operation of the cylinder discriminating circuit is similarly stopped by increasing the slice level and stopping the output of the waveform shaping circuit. Misfires are prevented during start-up noise.

[0024]

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will now be described with reference to FIGS.
This will be described below. FIG. 1 is a system diagram showing the entire system of an internal combustion engine according to this embodiment. In this embodiment, a six-cylinder engine is considered. The engine 1 is provided with an ignition coil 4 for each cylinder. The cylinder discrimination sensor 2 is directly connected to the camshaft. A projection 7 is set at a reference position on a plate 8 connected to the crankshaft.
The reference position sensor 6 is installed with a gap of about 1 mm from the plate 8 and the protrusion 7 respectively. The sensor group is a magnetic pickup type sensor, and is configured to convert a change in magnetic flux due to the protrusion 7 into an electric signal.
When the engine 1 starts rotating, the cylinder discrimination signal 2a is output from the cylinder discrimination sensor 2 and the reference position signal 6 is output from the reference position sensor 6.
a, an angle signal 5a is generated from the angle sensor 5, and these signal groups are input to the engine controller 10.
The engine controller 10 also receives a starter signal 105a from the starter switch 105, a water temperature signal 11a from the water temperature sensor 11, and a battery voltage 53a from the battery 53, and determines the optimum ignition timing and fuel injection amount based on these signals. Calculate. As a result, it is configured to output ignition signals 109a to 109f to the ignition device 9 and fuel injection signals 101c to 101h to the injector 3 that supplies fuel to the internal combustion engine 1, respectively.

FIG. 2 is an internal block diagram of the engine controller 10 which is a main part of the internal combustion engine control device of the present embodiment. Reference numeral 101 denotes a CPU that performs an engine control operation;
Numeral 02 is a waveform shaping circuit for shaping the input waveforms from the magnetic pickup type sensors 2, 5, 6 and is composed of three identical circuits. Reference position waveform shaping circuit for shaping the reference position signal 6a is 106, 107 angle waveform shaping circuit for shaping the angle signal 5a, 108 are cylinder discrimination signal 2 a
Is a cylinder discriminating waveform shaping circuit for shaping. Reference numeral 103 denotes a reference angle signal generation circuit that generates a reference angle signal 103a serving as a reference for control timings of the ignition signal 101b and the fuel injection signals 101c to 101h. 104 denotes the reference angle signal 103a, the cylinder discrimination waveform shaping signal 108a, and the reference position waveform. The cylinder is determined by taking in the shaping signal 106a and counting the number of output signals of the cylinder determination waveform shaping signal 108a between the reference position waveform shaping signals 106a, and each time the first cylinder is detected, one cylinder signal 104a to 6 cylinder signal is output. A cylinder discriminating circuit for generating 104f, an electronic distribution circuit 109 for electronically distributing the ignition signal 101b as the ignition signals 109a to 109f to the cylinders in the ignition order, and 105, which is not shown, is set to an ignition key switch. , Starter signal 105 for activating starter 52 (see FIG. 6)
a is a starter switch for sending out a.
An ignition device for energizing the ignition coil based on 9a to 109f, an injector for injecting fuel based on the output of the fuel injection signal 101c to 101h sent from the CPU 101, and a water temperature 11 for detecting a cooling water temperature Tw of the engine. A sensor 53 is a battery that supplies the voltage Vb to the engine controller 10, the starter 52, and the like.

In this block diagram, the reference position signal 6a,
The angle signal 5a and the cylinder discrimination signal 2a are supplied to the waveform shaping circuit 10
2 and the reference position waveform shaping circuit 106,
Angle waveform shaping circuit 107 and cylinder discriminating waveform shaping circuit 10
8 is output. The reference position waveform shaping signal 106a and the angle signal 5a which are the shaped waveforms of the reference position signal 6a.
The angle waveform shaping signal 107a which is the waveform after shaping is sent to the reference angle generation circuit 103 and the CPU 101. The reference angle generation circuit 103 converts the reference angle signal 103a into the cylinder discrimination circuit 104 and the CPU 10 based on the reference position waveform shaping signal 106a and the angle waveform shaping signal 107a.
Output to 1. The cylinder discrimination shaping waveform 108a, which is the post-shaping waveform of the reference angle signal 103a, the reference position waveform shaping signal 106a, and the cylinder discrimination signal 2a, is
, And the cylinder discriminating circuit 104 outputs a one-cylinder signal 104a every time the first cylinder is discriminated based on the signal group.
U101, and each time the first to sixth cylinders are determined, one-cylinder signals 104a to six-cylinder signals 10
4f is output to the electronic distribution circuit 109. In addition, a starter signal 105a, which is a start signal of the starter 52, a water temperature signal 11a sent from a water temperature sensor 11 for detecting a cooling water temperature Tw of the engine, and a battery voltage 53a sent from a battery are also input to the CPU 101. CPU 101
Then, the ignition timing, fuel injection amount, and the like are calculated based on the signal group so as to achieve optimal engine control, and the ignition signal 101b for controlling the operation of the ignition device 9 and the fuel injection signals 101c to 101h for controlling the operation of the injector 3 And mask signal 101 for controlling permission of operation of cylinder discriminating circuit 104
a and the like are output. The mask signal 101a functions to prohibit the operation of the cylinder discriminating circuit 104 when HIGH, and to permit the operation of the cylinder discriminating circuit 104 when LOW.

The electronic distribution circuit 109 has a one-cylinder signal 104a.
The ignition signal 101b output from the CPU 101 based on the .about.6 cylinder signal 104f is distributed to the cylinders in the ignition order as the ignition signals 109a to 109f.

FIG. 3 shows the magnetic pickup type sensor 2,
It is a timing chart showing the signal specification of 5 and 6. The reference angle signal 103a is a signal that rises based on the reference position signal 6a, falls after counting the angle signal 5a a predetermined number of times (for example, 15 counts). In addition, one cylinder signal 104
a counts the number of cylinder discrimination signals 2a between the reference position signals 6a, and every time one cylinder is detected, the reference angle signal 103 is calculated.
It is designed to output a signal in synchronization with the fall of a. The same applies to the 2 to 6 cylinder signals 104b to 104f.
FIG. 3B is an enlarged view of the reference position signal 6a, which is a magnetic pickup signal.
This is an analog signal waveform in which a + voltage is first generated with reference to V, and then decreases to a-voltage. Although only the reference position signal 6a has been described here, the cylinder discrimination signal 2a and the angle signal 5a are similar magnetic pickup signals. However, in this circuit, since the voltage level of the signal group of the analog specification changes depending on the number of revolutions of the engine, the signal level of the CPU or a peripheral circuit is shaped into a digital signal through the waveform shaping circuit 102 and used.

FIG. 4 is a diagram for explaining a specific circuit of the waveform shaping circuit 102 and its operation. Here, the reference position waveform shaping circuit 106 will be described. Reference numerals 110 and 111 are resistors for determining the signal detection level of the input reference position signal 6a. The resistor 110 is connected to a constant voltage power supply Vcc (for example, 5 V), and the voltage divided by the resistor 111 becomes a slice level 112 a and is input to the + terminal of the comparator 112. On the other hand, the reference position signal 6a is input to the negative terminal of the comparator 112, and the slice level 112
a is compared with the voltage level. As shown in FIG. 4B, when the reference position signal 6a is lower than the slice level 112a, the output 112b of the comparator 112
4, a signal of the Vcc level (HIGH) is output, input to the base terminal of the transistor 116, the transistor 116 is turned on, and the reference position waveform shaping signal 106 is output.
a becomes LOW. Next, when the reference position signal 6a exceeds the slice level 112b, the comparator output 112
b becomes LOW, the transistor 116 is turned off, and the reference position waveform shaping signal 106a has the Vcc voltage
5, and HIGH is output as the signal level. When the comparator output 112b becomes LOW, the slice level 112a is lowered by the resistor 113. When the reference position signal 6a falls below the slice level 112a again, the comparator output 112b goes high.
It becomes IGH and returns to the initial state. With the above operation, the waveform of the magnetic pickup signal is shaped.

The angular waveform shaping signal 1 whose waveform has been shaped above
A configuration for outputting the ignition signal 101b based on a signal such as 07a will be described with reference to FIG. FIG. 5A shows the ignition signal 101b.
FIG. 2 is a block diagram showing an output method of the CPU 1;
01. FIG. 3B shows the signal specifications. Reference numeral 30 denotes an ignition timing counter that counts the angle waveform shaping signal 107a based on the reference angle signal 103a and sets the ignition timing, and 31 denotes a data bus 1 in the CPU.
An ignition timing register 32 for setting a predetermined ignition timing based on the ignition timing data sent from the ignition timing counter 30c.
An ignition timing comparator that compares data set to 1 and outputs a HIGH signal when the two data match. Reference numeral 33 denotes an energization time counter which counts the angle waveform shaping signal 107a based on the ignition timing signal 32a, which is an ignition timing comparator output signal, and sets the energization time. Reference numeral 34 denotes a predetermined energization time based on energization time data transmitted from the data bus 101c. An energization time register 35 for setting the energization time. An energization time comparator 35 compares the data fetched by the energization time counter 33 with the energization time data set in the energization time register 34, and outputs a HIGH signal when both data match. It is. 36 is an ignition timing comparator 3
2 outputs a LOW signal when a HIGH signal is input to a reset terminal (R), and outputs a HIGH signal when a HIGH signal is input from a conduction time comparator 35 to a set terminal (S).
This is a flip-flop that outputs an H signal.

In FIG. 5, data of a predetermined ignition timing is first stored in an ignition timing register 31 from a data bus 101c.
Data of a predetermined energization time is sent to the energization time register 34. In the ignition timing counter 30, the reference angle signal 103
The angle shaping signal 107a is counted based on a, and a count signal is sent to the ignition timing comparator 32. The ignition timing register 31 outputs a signal corresponding to the ignition timing data transmitted from the data bus 101c to the ignition timing comparator 32.
To send to. In the ignition timing comparator 32, a signal sent from the ignition timing counter 30 and an ignition timing register 3
1 is compared with the signal sent from the ignition timing counter 30.
The ignition timing signal 32a is set to HIGH when the signal transmitted from the ignition timing register 31 matches the signal transmitted from the ignition timing register 31.
To the flip-flop 36. The flip-flop 36 outputs a LOW signal when the HIGH signal is input to the reset terminal ( R ). That is, the ignition signal 101b is set to LOW. In the energization time counter 33, the ignition timing signal 3 sent from the ignition timing comparator 32
The angle waveform shaping signal 107a is counted based on 2a, and a count signal is sent to the energization time comparator 35.
The energization time register 35 sends a signal corresponding to the energization time data sent from the data bus 101c to the energization time comparator 35. The power-on time comparator 35 compares the signal transmitted from the power-on time counter 33 with the signal transmitted from the power-on time register 34, and the signal transmitted from the power-on time counter 33 matches the signal transmitted from the power-on time register 34. At this time, the energization time signal 35a is sent to the flip-flop 36 as HIGH. When the HIGH signal is input to the flip-flop 36,
Outputs a HIGH signal. That is, the ignition signal 101b is set to HIGH. Hereinafter, the procedure of setting the ignition signal to LOW is repeated. Thus, the control of the ignition signal 101b
It is set by predetermined data input to the ignition timing register 31 and the energization time register 34.

Here, a mechanism of generating noise in the signal such as the reference position signal 6a at the time of starting the starter will be described with reference to FIGS. FIG. 6 is a block diagram illustrating the principle of generating noise in the crank angle sensors (sensors 2, 5, and 6). Reference numeral 51 denotes a crankshaft that transmits the power of the engine 1, and 52 denotes a starter that supplies a voltage from the battery 53 and starts the engine 1. Reference position signal 6
a and a plate 8 for generating the angle signal 5a are connected to the crankshaft 51 and mounted between the engine 1 and the transmission 50. The angle sensor 5 and the reference position sensor 6 are similarly installed between the engine 1 and the transmission 50. The cylinder discrimination sensor 2 is attached to the front of the engine 1 and is directly connected to a cam shaft. 52a is a starter current that flows when the starter is started. First, when the starter 52 starts, the starter 52 tries to rotate the crankshaft 51. At this time, since the torque required for rotating the crankshaft 51 is large, the starter current 52a flows through a path as shown. This transient current, a starter 52, engine 1 and the crankshaft 51
It flows into the flop rate 8 via a transmission 5
Returning to the battery 53 via 0. At this time, since a large current flows in the vicinity of the reference position sensor 6 and the angle sensor 5, the magnetic flux of these magnetic pickup sensors is changed to generate noise.

Next, the generation timing of the noise is shown in the timing chart of FIG. 105a is a starter signal when the starter is activated, and when the starter 52 is activated,
The starter signal 105a becomes HIGH. At this time, a large transient current flows through the starter current 52a for a certain time T1 (30 to 40 ms) from the start of the starter. The noise generated in the reference position signal 6a and the reference position waveform shaping signal 106a is such that the starter current waveform 53a has a transient region T1.
Is generated according to the above principle. This allows
Noise also occurs in the reference position waveform shaping signal 106a that is the shaping waveform. The same noise is generated not only in the reference position signal 6a but also in the angle signal 5a. As a result, the ignition signal 101 generated as described above is generated.
b (109a-109f) and the fuel injection signal 101c-
There is a problem that the ignition device 9 and the injector 3 malfunction due to erroneous output of 101h.

Therefore, in the present embodiment, the influence of the noise is prevented by stopping the operation of the cylinder discriminating circuit 104 only while the noise at the starter start is generated. 8 to 10 are diagrams showing the processing contents.

FIG. 8 is a block diagram showing the internal configuration of the cylinder discriminating circuit 104. 140 is a reference position waveform shaping signal 106
The counter circuit 141 counts the cylinder discriminating waveform shaping signal 108a input during the period a, the latch circuit 141 latches the signal output from the counter circuit 140 by the signal of the reference angle signal 103a, and the latch circuit 142 receives the signal from the latch circuit. From the one-cylinder signal 104a to the six-cylinder signal 1
This is a decoding circuit for distributing the data to the decoder 04f. The reference position signal 6a and the cylinder discrimination signal 2a input to the engine controller 10 are as shown in FIG. 3, and the cylinder discrimination is performed by counting the number of cylinder discrimination signals 2a generated between the reference position signals 6a. Performed by That is, the cylinder discrimination signal 2a is detected because the number of pulses generated for each cylinder differs. The counter circuit 140 counts the number of cylinder discrimination waveform shaping signals 108a between the reference position waveform shaping signals 106a obtained by shaping the waveform of the reference position signal 6a. The counted value is sent to the latch circuit 141 as binary data. The latch circuit 141 latches the data at the timing when the reference angle signal 103a falls, and inputs the latched data to the decode circuit 142. In the decoding circuit 142, for example, when the latched binary number data is 1, the reference position signal 6a generated next indicates that of the second cylinder, so that the two-cylinder signal 104b
To HIGH. Similarly, if the latched data is 6, it indicates one cylinder, and the one-cylinder signal 104a is set to HI.
This is a configuration for making GH. A mask signal 101a (described later) is input to a reset terminal of the latch circuit 141.
When the mask signal 101a is HIGH, the latch circuit 14
The data of 1 is cleared, and the data of 0 is
42. When 0 data is input to the decoding circuit 142, no cylinder signal is output to any output signal. As a result, the cylinder discriminating operation is stopped. FIG. 9 is a block diagram showing the internal configuration of the electronic distribution circuit 109. The basic configuration is to make each cylinder signal 1
The AND gates 04a to 104f are ANDed with signals obtained by shifting the one-cylinder signal 104a to the ignition position. 12
A shift register 0 shifts the one cylinder signal 104a to the position of the ignition cylinder by the ignition signal 101a, and 121 to 132 are AND circuits for ANDing the cylinder signals 104a to 104f. Reference numerals 120a to 120f denote 1-cylinder ignition position signals to 6-cylinder ignition position signals, respectively.
Reference numerals 9a to 109f denote ignition signals of one cylinder to six cylinders, respectively. Reset terminal R of shift register 120
Is a mask signal 101a, a data input terminal D is a one-cylinder signal 104a, and a clock input terminal CK is an ignition signal 10a.
1b are input.

FIG. 10 is a timing chart showing the operation of the cylinder discriminating circuit 104 and the electronic power distribution circuit 109. Each of the cylinder discrimination signals 104a to 104f counts the number of pulses of the cylinder discrimination signal 2a between the reference position signals 6a as described in the operation of the cylinder discrimination circuit 104, and is output at the timing of the reference angle signal 103a. On the other hand, in the shift register 120 in the electronic distribution circuit 109, the one-cylinder signal 104a is shifted by the ignition signal 101b,
These are output as ignition position signals 120a to 120f, respectively. In the AND circuits 121 to 126, each of the cylinder signals 1
The logical product of the ignition position signals 04a to 104f and the ignition position signals 120a to 120f is calculated. This is because if the output position of the shift register 120 is a normal position, ignition is output, and if it is output to a different position, no ignition is output. The outputs of the AND circuits 121 to 126 again output the ignition signal 101b and the signal
The logical product is obtained by the D circuits 127 to 132 and output as cylinder ignition signals 109a to 109f according to each cylinder. Now, the mask signal 101a is
0, the mask signal 10
When 1a becomes HIGH, the ignition position signals 120a to 120f of the respective cylinders, which are the outputs of the shift register 120, become LOW.
Thus, the ignition signals 109a to 109f of each cylinder are not output. When the mask signal 101a is input as described above, the electronic distribution circuit 109 causes each of the cylinder ignition signals 109
The output of a to 109f is stopped.

Further, in the apparatus which also controls the fuel injection as in the present embodiment, erroneous fuel injection occurs due to the noise at the time of starting. That is, as shown in FIG.
One cylinder signal 10 due to erroneous cylinder determination due to noise at start
If 4a occurs erroneously, the fuel injection position will deviate from the normal position. Originally, the fuel injection position was set immediately before the air supply valve opened. Therefore, if the fuel injection position is shifted, the fuel may be injected after the intake valve is closed, so that a phenomenon that the fuel is not sucked occurs. Further, the fuel injection signal 101h of the sixth cylinder is lost.

In this embodiment, during the period in which the operation of the cylinder discriminating circuit 104 is stopped, the fuel injection signals 101c to 101c to
By stopping the distribution of 1h, erroneous fuel injection due to the noise is also prevented. FIG. 12 is a flowchart showing the processing contents. The program shown in this chart is started at regular intervals (for example, every 10 ms).

In FIG. 12, at S1, the mask signal 10
1a is determined, and the mask signal 101a is set to HIGH.
If it is (ON), the process proceeds to S2, and the fuel injection is stopped. When the mask signal 101a is LOW (OFF), the process proceeds to S3. In S3, the presence or absence of the one-cylinder signal 104a is determined, and
When it is determined that the cylinder signal 104a is ON and the cylinder is one cylinder,
In S4, the counter is set to 1, and the process proceeds to S5. 1 cylinder signal 1
When it is determined that 04a is OFF and not one cylinder, the process proceeds to S6, the counter is updated (1 is added), and the process proceeds to S5. S5
Then, fuel is injected into the cylinder of the counter. When the fuel injection to all six cylinders is completed, the one-cylinder signal 104a is turned on again, and the fuel injection to each cylinder is sequentially repeated. As described above, erroneous fuel injection due to generation of noise at the time of starting is prevented. That is, S3 to S6 constitute second distribution means for distributing the fuel injection signals in the order of ignition based on the one cylinder signal 104a from the cylinder discrimination circuit 104, and S1 and S2 stop the operation of the cylinder discrimination circuit 104. During the period, fuel distribution stop means for stopping distribution of the fuel injection signal by the second distribution means is constituted.

The mask signal 101a is generated and output in the CPU 101. FIG. 13 is a flowchart showing the content of the output control of the mask signal. The program shown in this chart is started at regular intervals (for example, every 10 ms).

In FIG. 13, in S11, it is determined whether the starter 52 is currently being started or stopped. The determination uses the starter signal 105a. If it is determined in S11 that the engine is not being started, the process proceeds to S12, in which the mask signal 101
The flag for judging whether or not the output of a for a predetermined period has been completed is reset (flag = 0), and the process proceeds to S18. S18
Then, the output of the mask signal 101a is stopped (OFF), that is, L
Set to OW and end this flow. An interrupt occurs again, and the starter signal 105a is turned on in S11 and the starter 5
When it is determined that 2 is starting, the process proceeds to S13, and it is determined whether the mask signal 101a is being output. When it is determined that the mask signal 101a is not being output, the process proceeds to S17, and it is determined whether the flag is 1 or not. When the flag is reset (flag = 0), since the mask signal has not been output yet, the process proceeds to S15, and the mask signal 101a
(ON), that is, HIGH, and the timer is ON
Then, this flow ends. Interrupt occurs again and S1
If it is determined in step S1 that the starter 52 is being started, and if it is determined in step S13 that the mask signal 101a is being output, the process proceeds to step S13.
Proceeding to 14, it is determined whether the timer has passed a predetermined time T1. That is, it is determined whether the mask signal 101a has been output for a predetermined period. Here, the timer is set to a predetermined time T.
If it is determined that 1 has not elapsed (the mask signal 101a has not been output for a predetermined period), the process proceeds to S15, where the mask signal 101a is output again and the timer is kept ON. When it is determined that the timer has passed the predetermined time T1 (the mask signal 101a has been output for the predetermined period), the process proceeds to S16,
Set the flag (flag = 1) and turn off the timer
Then, the output of the mask signal 101a is stopped in S18. After a certain period of time, an interrupt occurs again, and the starter 52
Is determined to be in operation, and if it is determined in S13 that the output of the mask signal 101a is stopped, the process proceeds to S17. S1
At 7, it is determined whether or not the flag is set, and the flag is set (flag = 1), that is, the mask signal 101 is set.
When it is determined that a has been output for a predetermined period, the process proceeds to S18, where the output of the mask signal 101a is stopped (OFF), and the flow ends. As described above, the mask signal is output for a predetermined period immediately after the starter signal is input, and the cylinder discriminating circuit 1
By stopping the operation of 04, the distribution of the ignition signal can be stopped, and the distribution of the fuel injection signal can be stopped during the period in which the operation of the cylinder determination circuit is stopped.

The predetermined period of S14 in the flowchart, that is, the predetermined time T1 of the timer is set as shown in FIG. FIG. 14A is a graph showing the relationship between the engine cooling water temperature Tw and the predetermined time T1.
(B) is a graph showing the relationship between the battery voltage Vb and the predetermined time T1. In FIG. 14A, the predetermined time T1 is set longer as the cooling water temperature Tw of the engine is lower. The reason for this setting is that the engine coolant temperature T
The lower the w, the greater the load when starting the engine,
This is because a larger transient current flows through the above-described starter current path 52a, and the period during which noise occurs becomes longer. on the other hand,
When the cooling water temperature Tw of the engine is high, the load at the time of starting the engine is small, and the transient current flowing through the above-described starter current path 52a is also small. The predetermined time T1 is set short so as not to output the mask signal 101a.

Similarly, in FIG. 14B, the predetermined time T1 is set longer as the battery voltage Vb is lower, and the predetermined time T1 is set shorter as the battery voltage Vb is higher.
This is for the same reason as above. Thus, the mask signal 1
The influence of noise can be effectively prevented by setting the output period of 01a based on the engine cooling water temperature Tw and the battery voltage Vb.

In the above embodiment, the output period of the mask signal 101a is set by the timer. However, the CPU 101 counts the reference position waveform shaping signal 106a, which is the shaped waveform of the reference position signal 6a, and outputs the reference position waveform shaping signal 10a.
It is also considered effective to output the mask signal 101a until the 6a signal is generated a predetermined number of times. FIG.
Shows such an embodiment. In the figure, steps having the same functions as those in FIG. 13 are denoted by the same reference numerals.
In this flowchart, when it is determined in S11 that the starter 52 is currently being started, the process proceeds to S19, in which the reference position waveform shaping signal 106a is input, and then proceeds to S13.
In S15A, the mask signal 101a is output (ON).
At the same time, the counter starts counting the signal 106a. On the other hand, it is determined whether the S1 4, the count number from the signal 106a of the counter depending on whether the predetermined number of occurrences for a predetermined time period the mask signal 101a is output. If it is determined that the signal 106a has been generated a predetermined number of times, S16
Go to A , set the flag (flag = 1),
Reset the counter to 0. Also in this case, the mask signal is output for a predetermined period immediately after the input of the starter signal, thereby preventing malfunction of the internal combustion engine control device.

FIGS. 16 and 17 show a second embodiment of the present invention.
This will be described below. In the above-described embodiment, the mask signal 101a is directly transmitted to the cylinder discriminating circuit 104 to stop the cylinder discrimination. However, the same can be achieved by stopping the operation of the circuit that outputs one of the input signals of the cylinder discriminating circuit 104. The goal can be achieved. This embodiment shows one example.

That is, as described above, the cylinder discriminating circuit 104 outputs the reference position waveform shaping signal 106a and the cylinder discriminating shaped waveform 10
8a, the reference angle signal 103a is input to perform cylinder discrimination. Thus, in the present embodiment, the operation of the cylinder discriminating circuit 104 is stopped by stopping the operation of the reference angle generation circuit 103 only while noise is occurring in the reference position waveform shaping angle signal 106a, and the influence of the noise is reduced. To prevent. For this reason, the engine controller 10 of the present embodiment
At A, as shown in FIG. 16, the mask signal 101a is input to the reference angle generation circuit 103A. FIG. 17 shows the processing contents of the reference angle generation circuit 103A.

FIG. 17A is a block diagram showing details of the reference angle signal generation circuit 103A in FIG. 16, and FIG. 17B is a timing chart. In the reference angle signal generation circuit 103A, reference numeral 150 denotes a fall detection circuit for detecting the fall of the reference position waveform shaping signal 106a as an input signal, and 151 denotes the fall signal 1
A counter circuit that counts the angular waveform shaping signal 107a a predetermined number of times with reference to 50a, 103a is a reference angle signal output from the counter circuit, 101a is input to a reset terminal (R) of the counter circuit, and is used to operate the counter circuit during a mask period. This is the aforementioned mask signal for stopping the operation. The fall detection circuit 150 takes in the reference position shaping signal 106a and outputs a fall signal 150a based on the fall of the reference position shaping signal 106a. The falling signal 150a is input as a reference signal of the counter circuit 151, and the counter circuit 151 uses the falling signal 150a as a reference to form the angular waveform shaping signal 107.
a is started, and the reference angle signal 103a is counted only for a predetermined period.
Is output. At this time, the mask signal 101a becomes HIGH.
In the case of (ON), the counter circuit 151 stops operating,
The output of the reference angle signal 103a also stops. Mask signal 1
01a is output from the CPU 101 by the method shown in the flowchart of FIG. 13 or FIG. This allows
The operation of the cylinder discriminating circuit 104 in which the reference angle signal 103 is one of the input signals is also stopped, the output of the one-cylinder signals 104a to 104c is also stopped, and the operation of the electronic power distribution circuit 109 is stopped. In this embodiment, the reference angle signal 1
Also, the output of the ignition signal 101b output with reference to 03 is stopped, and the operation of the electronic distribution circuit 109 is stopped twice. By stopping the operation of the electronic distribution circuit 109, the operation of the ignition device 9 also stops. Further, similarly to the ignition signal 101b, the output of the fuel injection signals 101c to 101h output based on the reference angle signal 103a is also stopped, and the fuel injection by the injector 3 is stopped.

In addition to the above method, the waveform shaping circuit 102
By stopping the operation, the object of the present invention can be achieved. 18 and 19 show the embodiment. That is, in FIG. 18, the mask signal 101a is input to the waveform shaping circuit 102B of the engine controller 10B. As described above, the reference position signal 6a and the cylinder discrimination signal 2a are input to the cylinder discrimination circuit 104 via the reference position waveform shaping circuit 106 and the cylinder discrimination waveform shaping circuit 108, respectively. Further, the reference position signal 6a and the angle signal 5a
Are input to the reference angle generation circuit 103 via the reference position waveform shaping circuit 106 and the angle waveform shaping circuit 107, respectively. Therefore, unless the reference position waveform shaping signal 106a, the angle waveform shaping signal 107a and the cylinder discriminating waveform shaping signal 108a are input by the mask signal 101a, the cylinder discriminating circuit 104 does not operate, and the ignition signal 101b and the fuel injection signal 101c. 〜１０101h are not output. Hereinafter, the specific processing will be described with reference to FIG. 19 in the case where the output of the reference position waveform shaping signal 106a is stopped.

In FIG. 19, (a) is a circuit configuration, (b)
Is a timing chart for explaining the operation. Reference position signal 6
a is input to the comparator 112 as in FIG. 4 and compared with the slice level 112a. The transistor 116 is turned on / off by the signal of the comparator output 112b to output the reference position waveform shaping signal 106a. The mask signal 101a is input to the base of the transistor 117 via the resistor 118, and the mask signal 101a is set to HIGH (O
N), even if the transistor 117 is turned on and the transistor 116 is turned off, the reference position waveform shaping signal 10
6a is set to LOW. The prevention of malfunction due to starter noise will be described with reference to the timing chart of FIG. 2B. Immediately after the starter signal 105a is input, noise enters the reference position signal 6a and the slice level 11 of the comparator 112
The comparator output 112b is output beyond 2a. At this time, in order not to input the noise signal to the CPU 101, the reference angle generation circuit 103, and the cylinder discrimination circuit 104, the transistor 117 is turned on by the mask signal 101a and the reference position waveform shaping signal 106a is set to LOW. The mask signal 101a is output from the CPU 101 by the method shown in the flowchart of FIG. 13 or FIG. This makes it possible to mask the noise from the starter,
Malfunction of the internal combustion engine control device can be prevented.

In the above-described embodiment, since the starter noise is masked by the mask signal 101a to stop the operation of the circuit and prevent a malfunction, there is still a problem that the startability is deteriorated. As a method for solving the problem, a method in which noise is not detected by the waveform shaping circuit 102 itself may be considered. The embodiment will be described below with reference to FIGS.

In FIG. 18, the mask signal 101
Although “a” inhibits the operation of the waveform shaping circuit 102B, it is possible to remove noise caused by the starter current 52a by using the mask signal 101a as a signal for changing the slice level 112a of the waveform shaping circuit 102B. It becomes possible. FIG. 20 is a circuit diagram incorporating a configuration for changing the slice level of the waveform shaping circuit 102B, and FIG. 21 is a timing chart for explaining the operation of the circuit shown in FIG. In the reference position waveform shaping circuit 106C shown in FIG.
A pnp-type transistor that turns on when it becomes OW, 162
Is an npn-type transistor which is turned on when the base signal becomes HIGH, and 161, 163 and 164 are resistors. Now, when the mask signal 101a is LOW (OFF), the transistor 162 is turned off and the current is cut off.
The base voltage of the transistor 160 becomes HIGH, and the transistor 160 is turned off. Transistor 160 has p
Since the transistor is an np transistor, the current is interrupted when the transistor is turned off. As a result, the slice level 112a is set by the voltage division of the resistors 110 and 111. On the other hand, when the mask signal 101a is HIGH (ON), the transistor 16
2 is ON, and the base voltage of the transistor 160 is L
It becomes OW and turns on the transistor 160. When the transistor 160 is turned on, the resistor 164 is inserted in parallel with the resistor 110. Therefore, the voltage of the slice level 112a is determined by the combined resistance of the resistors 164 and 110 and the divided voltage of the resistor 111. Also has a high voltage.

The specific operation will be described with reference to FIG. 21. When the mask signal 101a is LOW, the slice level 112a
Is set to a low voltage, starter noise may be detected as a normal signal. On the other hand, when the mask signal 101a is HIGH, the slice level 112b is set to a high voltage, and noise is not detected.

As described above, the waveform shaping circuit 1 is provided only for a predetermined period.
By changing the slice level 112b of 06C,
Noise is not detected, and ignition control or fuel injection control does not malfunction. The output control method and the output period of the mask signal 101a are the same as those shown in FIG.
15 are output by the method shown in FIG.

In the above embodiment, the reference position waveform shaping circuit 106 is used.
Although the angle waveform shaping circuit 107 and the cylinder discriminating shaping circuit 108 perform the same operation, the effect of preventing malfunction is increased. Thus, according to the present embodiment,
The effect of noise can be effectively prevented.

[0056]

[0057]

[0058]

According to the present invention, in an internal combustion engine control device having a cylinder discriminating function, it is possible to eliminate the influence of noise generated when the starter is started with a simple configuration and prevent erroneous ignition. Further, erroneous fuel injection and erroneous fuel injection can be prevented with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a diagram showing an entire system of an internal combustion engine control device according to the present invention.

FIG. 2 is a block diagram showing an internal combustion engine control device according to the first embodiment of the present invention.

FIG. 3 is a timing chart showing signal specifications of the crank angle sensor shown in FIG.

4 is a circuit diagram of a waveform shaping circuit for a crank angle sensor signal shown in FIG. 2 and a timing chart showing its operation.

FIG. 5 is a block diagram showing an output method of an ignition signal in a CPU of FIG. 2;

FIG. 6 is a block diagram illustrating a principle of generating noise in the crank angle sensor.

FIG. 7 is a timing chart illustrating the principle of noise generation.

FIG. 8 is a block diagram showing an internal configuration of a cylinder discriminating circuit shown in FIG.

9 is a block diagram showing an internal configuration of the electronic distribution circuit shown in FIG.

FIG. 10 is a timing chart showing operations of a cylinder discrimination circuit and an electronic distribution circuit.

FIG. 11 is a diagram showing the reason why erroneous cylinder determination causes erroneous fuel injection.

FIG. 12 is a flowchart illustrating an operation of distributing fuel to each cylinder in the CPU of FIG. 2;

FIG. 13 is a flowchart showing the contents of output control of a mask signal in the CPU of FIG. 2;

FIG. 14 is a graph showing a method of setting a control time of a mask signal.

FIG. 15 is a flowchart illustrating another example of the content of the output control of the mask signal in the CPU of FIG. 2;

FIG. 16 is a block diagram showing an internal combustion engine control device according to a second embodiment of the present invention.

17 is a block diagram and a timing chart showing details of a reference angle signal generation circuit shown in FIG. 16;

FIG. 18 is a block diagram showing an internal combustion engine control device according to a third embodiment of the present invention.

19 is a circuit diagram of a waveform shaping circuit of the crank angle sensor shown in FIG. 18 and a timing chart showing an operation thereof.

FIG. 20 is a circuit diagram of a waveform shaping circuit having a configuration for changing a slice level of a crank angle sensor as a fourth embodiment of the present invention.

FIG. 21 is a timing chart for explaining the operation of the circuit shown in FIG. 20;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Engine 2 Cylinder discrimination sensor (rotation detecting means) 3 Injector 4 Ignition coil 5 Angle sensor (rotation detecting means) 6 Reference position sensor (rotation detecting means) 7 Projection 8 Plate 9 Ignition device 10 Engine controller 11 Water temperature sensor 30 Ignition timing counter 31 Ignition timing register 32 Ignition timing comparator 33 Energizing time counter 34 Energizing time register 35 Energizing time comparator 36 Flip-flop 50 Transmission 51 Crankshaft 52 Starter 53 Battery 101 CPU 102 Waveform shaping circuit (rotation detecting means) 103 Reference angle generating circuit (rotation) Detecting means) 104 Cylinder discriminating circuit 105 Start switch 106 Reference position waveform shaping circuit (Rotation detecting means) 107 Angle waveform shaping circuit (Rotation detecting means) 108 Cylinder discriminating waveform shaping circuit (Rotation detecting means) 109 Electronic distribution circuit (first distribution means) 110, 111, 113 to 115, 118 Resistance 112 Comparator 116, 117 Transistor 120 Shift register 121 to 132 AND circuit 140 Counter circuit 141 Latch circuit (cylinder determination stop) Means) 142 Decoding circuit 150 Fall detection circuit 151 Counter circuit (cylinder discrimination stop means) 160 Transistor 161, 163 Resistor 162 Transistor (cylinder discrimination stop means) 2a Cylinder discrimination signal 5a Angle signal 6a Reference position signal 11a Water temperature signal 32a Ignition timing Signal 35a Energization start signal 52a Starter current 53a Battery voltage 101a Mask signal 101b Ignition signal 101c Data bus 101c to 101h Fuel injection signal 103a Reference angle signal 104 1 cylinder signal 104b 2 cylinder signal 104c 3 cylinder signal 104d 4 cylinder signal 104e 5 cylinder signal 104f 6 cylinder signal 105a starter signal 106a Reference position waveform shaping signal 107a Angle waveform shaping signal 108a Cylinder discriminating waveform shaping signal 109a 1 cylinder ignition signal 109b 2 Cylinder ignition signal 109c Three cylinder ignition signal 109d Four cylinder ignition signal 109e Five cylinder ignition signal 109f Six cylinder ignition signal 112a Slice level (predetermined level) 112b Comparator output 120a One cylinder ignition position signal 120b Two cylinder ignition position signal 120c Three cylinder ignition position Signal 120d 4-cylinder ignition position signal 120e 5-cylinder ignition position signal 120f 6-cylinder ignition position signal 150a Fall signal S1 and S2 Fuel distribution stop means S3 to S6 Second distribution means S11 S19 cylinder discrimination stop means

Claims (12)

(57) [Claims] An engine having a plurality of cylinders; rotation detection means for detecting rotation of the engine; a cylinder determination circuit for determining a cylinder based on a signal from the rotation detection means; and a signal from the rotation detection means. And a first distribution unit that distributes an ignition signal corresponding to the ignition timing to the cylinders in the order of ignition based on a signal from the cylinder discrimination circuit. A cylinder discriminating stop means for stopping the operation of the cylinder discriminating circuit for a predetermined period immediately after the input of the engine start signal, and stopping the operation of the cylinder discriminating circuit to thereby stop the operation of the first distribution means. An internal combustion engine control device for stopping distribution of an ignition signal. 2. The internal combustion engine control device according to claim 1, wherein said means for calculating a fuel injection amount based on a signal from said rotation detecting means, and said fuel injection amount corresponding to a signal from said cylinder discriminating circuit. Second distribution means for distributing the fuel injection signal to the fuel injection device in the order of ignition; and fuel for stopping distribution of the fuel injection signal by the second distribution means during a period in which the operation of the cylinder discriminating circuit is stopped. An internal combustion engine control device comprising: a distribution stopping means. 3. The internal combustion engine control device according to claim 1, wherein the cylinder discrimination stop means stops the operation of the cylinder discrimination circuit for a preset time immediately after the start signal is input. Internal combustion engine control device. 4. The internal combustion engine control device according to claim 1, wherein the cylinder discriminating and stopping means is configured to start the cylinder from immediately after the input of the start signal until the signal from the rotation detecting means is generated a predetermined number of times. An internal combustion engine control device, wherein the operation of a determination circuit is stopped. 5. The internal combustion engine control device according to claim 1, further comprising means for detecting a cooling water temperature of the engine, wherein the predetermined period is set by the cooling water temperature of the engine. 6. The internal combustion engine control device according to claim 1, further comprising means for detecting a battery voltage, wherein said predetermined period is set by said battery voltage. 7. The internal combustion engine control device according to claim 1, wherein said rotation detecting means detects a magnetic pickup type reference position detector for detecting that a piston position of the engine is at a predetermined position, and said reference position detector. And a first waveform shaping circuit for shaping the waveform of the reference position signal from the controller. The cylinder discrimination stopping means stops the operation of the cylinder discrimination circuit by stopping the output of the first waveform shaping circuit. An internal combustion engine control device characterized by the following. 8. The internal combustion engine control device according to claim 1, wherein said rotation detecting means comprises a magnetic pickup type cylinder discriminating detector for detecting a cylinder discriminating signal for performing cylinder discrimination, and said cylinder discriminating detector. And a second waveform shaping circuit for shaping the waveform of the cylinder discriminating signal. The cylinder discriminating stopping means stops the operation of the cylinder discriminating circuit by stopping the output of the second waveform shaping circuit. An internal combustion engine control device characterized by the following. 9. The internal combustion engine control device according to claim 1, wherein said rotation detecting means includes a magnetic pickup type angle detector for detecting a rotation angle of a crankshaft of the engine, and an angle signal from said angle detector. A third waveform shaping circuit for waveform shaping, wherein the cylinder discrimination stopping means stops the operation of the cylinder discrimination circuit by stopping the output of the third waveform shaping circuit. apparatus. 10. The internal combustion engine control device according to claim 1, wherein said rotation detecting means includes a magnetic pickup type reference position detector for detecting that the piston position of the engine is at a predetermined position, and a rotation of the crankshaft of the engine. A magnetic pickup type angle detector for detecting a rotation angle; and a reference angle generation circuit for generating a reference angle signal from a reference position signal and an angle signal from the reference position detector and the angle detector. An internal combustion engine control device, wherein the stopping means stops the operation of the cylinder discriminating circuit by stopping the output of the reference angle generating circuit. 11. The internal combustion engine control device according to claim 1, further comprising a power distribution stop means for stopping the operation of the first distribution means for a predetermined period immediately after the input of the engine start signal. An internal combustion engine control apparatus characterized in that the distribution of the ignition signal in the first distribution means is stopped twice by the stop of the operation of the first distribution means in the stop means and the stop of the operation of the cylinder discriminating circuit. . 12. An engine having a plurality of cylinders, a magnetic pickup type rotation detector for detecting rotation of the engine, a waveform shaping circuit for waveform shaping a signal from the rotation detector, and a signal from the waveform shaping circuit. A cylinder discriminating circuit for discriminating a cylinder based on a signal, a means for calculating an ignition timing based on a signal from the waveform shaping circuit, and an ignition signal corresponding to the ignition timing based on a signal from the cylinder discriminating circuit. A control unit for sequentially distributing the cylinders to the cylinders, wherein the waveform shaping circuit changes a level of an output signal when a voltage level of a signal from the rotation detector exceeds a predetermined level; Means for increasing the predetermined level for a predetermined period immediately after the start signal of the engine is input, and increasing the predetermined level to increase the waveform. By stopping the output, the internal combustion engine control apparatus characterized by stopping the distribution of the ignition signal by the distribution means to stop the operation of the cylinder discrimination circuits.