JPH0674780B2 - Internal combustion engine ignition device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-power distribution type internal combustion engine ignition device that performs ignition distribution of a plurality of cylinders without using a distributor.

[Conventional technology]

FIG. 1 is a block diagram of an internal combustion engine ignition device previously filed by the same applicant (Japanese Patent Application No. 62-142702). In the figure, reference numeral 1 is a signal rotor, and two trigger poles 2a and 2b with an interval of 180 ° each have an angle θ ₁ θ ₂ of 45 ° corresponding to two cylinders distributed by a 4-cylinder engine on the outer periphery thereof. It is provided. Reference numeral 3 is a cylinder identification guide pole provided in front of the trigger pole 2a, and is arranged at a position where an angle θ ₃ between the front end of the trigger pole 2a and the front end of the trigger pole 2a is 22.5 °. A signal coil 4 is provided so as to be close to the trigger poles 2a, 2b and the guide pole 3 when the signal rotor 1 rotates, and its output is connected via a waveform shaping circuit 5 to a microcomputer 6 which is an ignition control device. There is. The microcomputer 6 has an input port 7, an input timer 8, an output timer 8, a CPU 10, a RAM 11, a ROM 12, and an output port 13.
The output of the waveform shaping circuit 5 is connected to the input port 7, and the output port 13 is connected to the amplifier circuits 14a and 14b. 15a and 15b are ignition coils whose primary coils are connected to amplifier circuits 14a and 14b, respectively, and the secondary coils of the ignition coil 15a are connected to a 1-cylinder ignition plug 16a and a 4-cylinder ignition plug 16b, respectively. The secondary coil of the coil 15b has a spark plug 16c for two cylinders and a spark plug 16d for three cylinders.
Are connected.

Next, the operation of the ignition device having the above configuration will be described with reference to the flowchart of FIG. 3 and the timing chart of FIG.

When the signal rotor 1 rotates in synchronization with the rotation of the engine,
In the signal coil 4, positive and negative angle signals corresponding to the guide pole 3 and the trigger poles 2a and 2b as shown in FIG. 4 (A) are generated. The waveforms in FIGS. 4 (A) to 4 (F) are the waveforms at points A to F in FIG. The angle signal output from the signal coil 4 is formed into a waveform by the waveform shaping circuit 5 (FIG. 4 (B)) and input to the microcomputer 6.

The microcomputer 6 obtains the period t _n , (n = 1,2,3 ... n, n + 1, ...) Of this signal in step S1, and in step S2
It compares the magnitude of t _n-1 multiplied by the t _n and 3/8. In this step S2 If so, the process proceeds to step S3, which is the reverse of step S2, and t _n
Multiply by and 3/8 to make a size comparison. here, If is greater than t _n-1 , proceed to step S4
The processing on the cylinder side is performed, and the microcomputer 6 sends out the signal shown in FIG. Also If is smaller than t _n-1 , the process proceeds to step S5 and the process on the guide pole side is performed.

Also, in step S2, t _n is If smaller, in step S6 It is determined whether is smaller than t _n-1 . here If it is, proceed to step S7, perform the process of the 1 and 4 cylinder side, If so, the processing on the guide pole side is performed in step S5. The microcomputer 6 is the fourth in the case of processing on the 1,4 cylinder side.
An ignition timing control signal for the 1,4 cylinder side as shown in FIG.

The ignition timing control signals for the 1,4-cylinder side (Fig. 4 (C)) and the ignition timing control signal for the 2,3-cylinder side (Fig. 4 (D)) sent from the microcomputer 6 are amplified by the amplifier circuits 14a, 14b. Is supplied to the ignition coils 15a and 15b via The ignition coils 15a and 15b are shown in FIGS. 4 (E) and 4 (F), respectively.
When the current is cut off, a high voltage is generated in the secondary coil, and spark discharge is performed by the spark plugs 16a, 16b and 16c, 16d.

Here, the concept of setting the coefficient will be described. In the above, the cycle T _n-1 measured last time or the cycle T _n measured this time
Is compared with the cycle Tn measured this time or the cycle Tn _-1 measured last time, which is the ratio Tn / T of the cycle measured this time and the cycle measured last time.
It is nothing but comparing _n-1 with the predetermined value 8/3 or the predetermined value 3/8. Tn / Tn _-1 is determined by the physical configuration, and there are only three values, 8/1, 7/8, and 1/7. Therefore,
To determine the cylinder, the calculated Tn / T _n-1 is 8/1, 7 /
It suffices to determine whether it is 8 or 1/7. However, in the present application, the angle is converted into a cycle to calculate Tn / T _n-1 , so that, for example, when the engine accelerates or decelerates to cause rotational fluctuation, the value of Tn / T _n-1 fluctuates accordingly. To do. Therefore, for example, even if an attempt is made to determine the cylinder based on whether Tn / Tn _-1 matches 8/1, it is unlikely that this will match. In the present application therefore, determines that the Tn / T _n-1 is the larger if Tn / T _n-1 than the predetermined value 8/3 is 8/1, likewise predetermined value
If it is between 8/3 and the predetermined value 3/8, it is determined as 7/8, and if it is smaller than the predetermined value 3/8, it is determined as 1/7. Therefore, the predetermined value 8
Speaking of / 3, 8/1> predetermined value> 7/8 is sufficient, and it does not have to be 8/3 separately. As described above, the value of Tn / Tn _-1 fluctuates during overdeceleration of the engine, so an actual overdeceleration test was performed to determine the cycle ratio Tn / Tn _-1.
It is more desirable to check how much is shifted and to set it so that even if the cycle ratio Tn / Tn _-1 shifts, it does not exceed the above-mentioned predetermined value 8/3 or the predetermined value 3/8.

[Problems to be Solved by the Invention]

The internal combustion engine ignition device configured in this way has achieved great results such as the signal distribution of a plurality of cylinders with only one signal coil. However, when the engine speed fluctuation is large, for example, at engine startup, etc. There is a risk that misfiring will occur, and if such misfiring occurs, there will be problems such as the occurrence of ketchin and, in extreme cases, damage to the engine, and these problems remain unsolved. It was

For example, if the previous cylinders were two or three cylinders, the cycle ratio Tn / Tn _-1 obtained by the current calculation is 7/8. At this time, if the engine is accelerating, the cycle measured this time becomes short, so the place where it is originally 7/8 may be a value such as 6/8, 5/8, 4/8 depending on the degree of acceleration. Yes, in the worst case, the above predetermined value becomes 3/8 or less, and there is a risk of misidentifying the cylinder. On the other hand, in the case of 1, 4 cylinders, the cycle ratio Tn / T
_Since the difference between _n-1 and the predetermined value to be compared is large, the cycle ratio Tn /
Even if T _n-1 becomes a little smaller, there is no worry as in the case of a few cylinders. Further, in the case of the guide pole, there is no problem because the difference from the predetermined value to be compared is in the direction of further opening.

For reference, the judgment in step S2 of FIG. 3 is shown in a table.

As is clear from Table 1, it is understood that the risk of erroneous determination is when the last cylinder was a few cylinders.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an internal combustion engine ignition device capable of preventing erroneous ignition even when the engine speed fluctuation is large.

[Means for Solving the Problems]

The internal combustion engine ignition device according to the present invention includes a cylinder discriminating means for measuring a period of a signal between each trigger pole and a guide pole, and discriminating a cylinder based on a ratio of a period measured last time and a period measured this time. The cylinder discriminating means selects the first predetermined value when the previously discriminated cylinder is not the predetermined specific cylinder, and when the previously discriminated cylinder is the predetermined specific cylinder, the cylinder discriminating means is more than the first predetermined value. A small second predetermined value is selected, and the cylinder is discriminated based on the ratio and the selected predetermined value.

[Operation] In the present invention, the cylinder discriminating means selects the first predetermined value when the previously discriminated cylinder is not a predetermined specific cylinder, and when the previously discriminated cylinder is a predetermined specific cylinder. Selects a second predetermined value that is smaller than the first predetermined value, and determines the cylinder based on the ratio between the cycle measured last time and the cycle measured this time, and the selected predetermined value. The tolerance for the engine speed fluctuation for discrimination is high, and therefore accurate cylinder discrimination is performed even when a large engine speed variation occurs.

〔Example〕

An internal combustion engine ignition device according to an embodiment of the present invention will be described below with reference to the drawings. Since the configuration on the drawing in the embodiment is the same as that in FIG. 1, its description is omitted here.

FIG. 2 is a flowchart showing the operation of the microcomputer 6 in the internal combustion engine ignition device. First, at step S11, the period t _n (n = 1, _{n of the} signal shown in FIG.
2,3, ... n, n + 1, ...) is obtained, and it is then determined in step S12 whether or not the previous cylinder determination result is 2,3. If the previous time was on the 2 or 3 cylinder side, the process proceeds to step S13, the previous cycle t _n-1 is multiplied by 2.25 / 8 and compared with the current cycle t _n , and the previous cylinder discrimination result is 2 or 3 cylinders. If not, step S
At 14, the previous cycle t _n-1 is multiplied by 3/8 and compared with the current cycle t _n . That is, if there is a fluctuation in the engine speed, especially when the engine speed suddenly increases when the engine is started, it is highly likely that an erroneous cylinder determination is performed, for example, in the cycle t _n in FIG. 4 (B).
And the cycle angular ratio is small, such as the cycle t _{n + 1} . Therefore, in this case, the coefficient to be multiplied is the first coefficient (3/8)
Smaller by comparing a second coefficient (2.25 / 8), for example at machine start moving, the rotational speed of the period t _n terminating in third cylinders side ignited by the engine of spikes, the periodic t _n- The comparison between t _n and t _n-1 is accurate even if ₁ is shortened.

If the current cycle t _n is larger than the cycle t _n-1 obtained by multiplying the second or first coefficient in steps S13 and S14, step S1
Go to 5 Is compared, and if not, in step S16 Make a comparison. In step S15 If it is, it proceeds to step S17, it is determined whether or not the previous cylinder discrimination result is the 1,4 cylinder side, and if it is the 1,4 cylinder side, the 2,3 cylinder side processing is performed in step S18. . Also in step S15 If not, the guide pole side processing is performed in step S19 if the previous time is not the 1,4 cylinder side in step S17. That is, in step S15 If it is determined that the cylinder discrimination is on the 2 or 3 cylinder side,
If the cylinder discrimination order is normal, the last cylinder discrimination result is 1,4.
It should be on the cylinder side. Therefore, in step S17,
By checking whether it is on the 1st or 4th cylinder side, it is judged whether or not the cylinders are in the normal cylinder discrimination order. The computer 6 does not send an ignition signal, so false ignition is prevented. Also, step S16
so If it is, it is the cylinder discrimination of the 1 and 4 cylinder side, so proceed to step S20 to check whether the previous cylinder discrimination result was on the guide pole side, and in the same order as in steps S17 and S18 If the cylinder is discriminated in step S2
At 1, the 1,4 cylinder side processing is performed. And in step S16 If not, or if it is determined in step S20 that the cylinder discrimination order is not normal, the process proceeds to step S19, and guide pole side processing is performed.

In the above embodiment, the first coefficient is 3/8 and the second coefficient is 2.2.
Although it is set to 5/8, the present invention is not limited to these numerical values, and the same effect as that of the above embodiment can be obtained even if the second coefficient is a numerical value smaller than the first coefficient.

〔The invention's effect〕

As described above, according to the present invention, the cylinder discriminating means makes the first determination when the previously discriminated cylinder is not a predetermined specific cylinder.
Is selected, and when the previously determined cylinder is a predetermined specific cylinder, a second predetermined value smaller than the first predetermined value is selected, and the previously measured cycle and the currently measured cycle are selected. Cylinders are discriminated based on the ratio and the selected predetermined value, so even if the engine speed suddenly changes, such as when the engine starts, the cylinders are accurately discriminated and misfire is prevented. Therefore, it is possible to prevent the ketchin and further prevent the engine from being damaged. Further, even if the fluctuation of the rotation speed is large, there is an effect that the engine startability is good because the misfire is less likely to occur.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an internal combustion engine ignition device according to an embodiment of the present invention, and FIG. 2 is a flowchart showing an operation procedure of cylinder discrimination of an internal combustion engine ignition device according to an embodiment of the present invention, FIG. FIG. 4 is a flow chart showing the cylinder discrimination operation of the conventional internal combustion engine ignition device, and FIG. 4 is an operation waveform diagram of each part of the internal combustion engine ignition device according to the present invention and the prior art. 1 ... Signal rotor, 2a, 2b ... Trigger pole, 3 ...
... guide pole, 4 signal coil, 6 microcomputer.

Claims (1)

[Claims] 1. A signal rotor that rotates in synchronism with the rotation of an internal combustion engine, a plurality of trigger poles provided on the outer periphery of the signal rotor in correspondence with the ignition position of each cylinder, and one of these trigger poles. A guide pole arranged in front of the trigger pole, a single signal coil for generating an angle signal corresponding to the angle of the trigger pole and the guide pole, and each trigger pole and guide based on a signal from the signal coil. Measure the period of the signal between the poles,
Cylinder discrimination means for discriminating the cylinder based on the ratio of the cycle measured last time and the cycle measured this time, and discrimination means for judging whether or not the discrimination result of this time is correct based on the discrimination result of the cylinder discrimination means last time, And an ignition control means for performing an ignition process for the cylinder determined this time when the determination means determines that it is correct. The cylinder determination means sets the first predetermined value when the previously determined cylinder is not a predetermined specific cylinder. If the selected cylinder is the specific cylinder determined in advance, the second predetermined value smaller than the first predetermined value is selected, and the cylinder is selected based on the ratio and the selected predetermined value. An internal combustion engine ignition device characterized by making a distinction.