JPH01224473A - Ignition device of internal combustion engine - Google Patents

Abstract

PURPOSE:To prevent misignition in an uneven distribution engine by performing cylinder judgement upon comparison of signaling intervals between trigger poles, and thereby having accurate cylinder judgement even in case the engine revolving speed has varied abruptly at the time of starting, etc. CONSTITUTION:At the periphery of a signal rotor 1, a plurality of trigger poles 2a, 2b are installed mating with the positions of cylinders where angle advance reference signal and initial signal are sent off. A signal coil 3 is installed to generate angle signal mating with the angles of these trigger poles 2a, 2b. An ignition control device 5 is furnished which is fed with the angle signal from this signal coil 3 through a waveform shaper circuit 4. At this time, the ignition control device 5 calculates ignition timing on the basis of angle signal of the signal coil 3, and performs cylinder judgement of the angle signal upon comparison of the signaling interval between the trigger poles 2a, 2b. Thereby the ignition control signals by cylinders are given to ignition plugs 15a, 15b.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ignition system for an internal combustion engine with uneven distribution, such as a multi-cylinder type engine.

[Conventional technology]

Figure 1 is a block diagram of an internal combustion engine ignition system that was previously filed by the same applicant (Japanese Patent Application No. 142703/1982).
In the figure, ■ is a signal rotor, and trigger poles 2a and 2b corresponding to each cylinder are provided on the outer periphery of the signal rotor. Further, this embodiment shows the case of a two-cylinder 90° ■ type engine, and if the angles of the respective trigger poles 2a and 2b are θ and θ3, and the angle between each trigger pole 2a and 2b is θ2, then θ8. θ2. The relationship between θ is θ1
+θ2=θ2+θ.

=90°, θ1=θ, #θ2. 3 is a signal coil, which is the trigger pole 2a when the signal rotor l5 rotates.
, 2b, and its output is connected via a waveform shaping circuit 4 to a microcomputer 5 which is an ignition control device. The microcomputer 5 has an input port controller and an input timer 7. Output tie, 78. CPU9.
RAMl0゜ROMI 1. The output port 12 is composed of an output port 12, and the output of the waveform shaping circuit 4 is connected to an input port, and the output port 12 is connected to amplifier circuits 13a and 13b. 14a and 14b are ignition coils whose primary coils are connected to amplifier circuits 13a and 13b, respectively.The secondary coil of the ignition coil 14a has a 1-cylinder spark plug 15a, and the secondary coil of the ignition coil 14b has a 2-cylinder spark plug 15a. A spark plug 15b for the cylinder is connected.

Next, the operation of the internal combustion engine ignition system having the above structure will be explained using the flowchart of FIG. 3 and the timing chart of FIG. 4.

When the signal rotor 1 rotates in synchronization with the rotation of the engine,
Positive and negative angle signals are generated in the signal coil 3 as shown in FIG. 4 (8). Note that the waveforms in FIGS. 4(A) to 4(F) show the waveforms at points A-F in FIG. 1. Signal coil 3
The angle signal outputted from is waveform-shaped by the waveform shaping circuit 4 (the s[J(B)), and is input to the microcomputer 5.

The microcomputer 5 determines the period of this signal La1ltLb+i(n=1+2+3+" in step S1)
'n-1+n+n+L''·). In other words, the trigger pole 12a.

Among the periods between 12b and 12b, the signal interval from the advance side to the initial side of the - set is compared with the interval from this initial side signal to the advance side signal of the next trigger pole. If -tb, l>t, R in step S2, step S3
, a predetermined ignition timing calculation for the first cylinder side is performed, and the output ignition timing control signal (FIG. 4 (C)) is sent to the amplifier circuit 1.
3a to the ignition coil 14a, and the ignition coil 14a is energized as shown in FIG. 4(E). Alternatively, the microcomputer 5 similarly calculates the ignition timing for the two cylinders, and the output signal ((0) in FIG. 4) is sent to the ignition coil 14 via the amplifier circuit 13a.
b, the ignition coil 14b is energized as shown in FIG. 4(F), and when the current is cut off, a high voltage is generated in the secondary coil, and the ignition plug 15b performs spark discharge.

[Problem to be solved by the invention]

The internal combustion engine ignition system configured in this way has achieved great results, such as being able to distribute signals to multiple cylinders with only one signal coil, but it is difficult to use when the engine speed fluctuations are large, such as when starting the engine. There is a risk of erroneous ignition, and if such erroneous ignition occurs, there are problems such as the occurrence of keratin and, in extreme cases, damage to the engine, and these problems remain unresolved issues. Ta.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an internal combustion engine ignition device that can prevent erroneous ignition even when the rotational speed of the engine varies greatly.

[Means to solve the problem]

The internal combustion engine ignition device according to the present invention is configured to discriminate between cylinders by comparing signal intervals between two trigger poles in an unequal distribution engine.

[For production]

In this invention, since the signal interval between two trigger poles is compared, the angular ratio between the signals is large;
Therefore, the tolerance to engine speed fluctuations for cylinder discrimination is high, and accurate cylinder discrimination can be performed even when large rotational speed fluctuations occur.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An internal combustion engine ignition system according to an embodiment of the present invention will be described below with reference to the drawings. Note that the configuration in the drawings in this embodiment is the same as that in FIG. 1, so the explanation thereof will be omitted here.

FIG. 2 is a flowchart showing the operation of the microcomputer 5 in the internal combustion engine ignition system.

First, in step Sll, the period of the signal shown in FIG.
+1+"'), and then in step 312 tbl
l and Lma-1, i.e., this is the fourth
The purpose is to compare the high level part of the waveform shown in Figure (B), and also the distance θ2 and 36o between the trigger poles 2a and 2b.

−(θ, +02〇,) and the signal intervals corresponding to θ, +020,) are compared. Therefore, since the angular ratio between the signals to be compared is large (approximately 5 times in the embodiment) and the tolerance to rotational speed fluctuations is high, accurate cylinder discrimination can be performed even if large rotational speed fluctuations occur. In step 312, tha>
j ha-+, in step S13 an ignition control signal is sent to the first cylinder side processing, that is, the amplifier circuit 13a,
If t.

In the above embodiment, a two-cylinder 90'' type engine was explained as an example of an unequally distributed engine in which the trigger poles 2a and 2b are formed unevenly on the signal rotor l, but the present invention is not limited to this. In the case of an engine with multiple cylinders with uneven distribution, the same effects as in the above embodiment can be achieved.

〔Effect of the invention〕

As described above, according to the present invention, in an unequal distribution organization,
Cylinder discrimination is performed by comparing the signal interval between the two trigger poles, so even if the engine speed changes suddenly, such as when starting the engine, cylinder discrimination is performed accurately and incorrect ignition is avoided. This has the effect of preventing ketching and, in turn, preventing damage to the engine.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an internal combustion engine ignition system according to an embodiment of the present invention and a conventional internal combustion engine ignition system, FIG. 2 is a flowchart showing an operation procedure for cylinder discrimination of an internal combustion engine ignition system according to an embodiment of the present invention, and FIG. 3 4 is a flowchart showing the cylinder discrimination operation of a conventional internal combustion engine ignition system, and FIG. 4 is an operation waveform diagram of each part of the internal combustion engine ignition system according to the present invention and the conventional one. ■...Signal rotor, 2a, 2b...Trigger pole, 3...Signal coil, 5...Microcomputer. Agent Masuo Oiwa Figure 2 Figure 3 (C) [D] (E) (F)

Claims (1)

[Claims] In an internal combustion engine ignition system for an unequal distribution engine in which ignition angle signals for a plurality of cylinders are generated in synchronization with the rotation of a signal rotor and are generated unevenly with respect to the rotation of the signal rotor,
two trigger poles provided on the outer periphery of the signal rotor at positions for sending advance angle reference signals and initial signals for two types of cylinders, and a signal coil that generates angle signals corresponding to the angles of these trigger poles; A predetermined ignition timing calculation is performed based on the signal from this signal coil, and 2
An ignition device for an internal combustion engine, comprising: an ignition control device that compares signal intervals between two trigger poles to discriminate between cylinders based on the angle signal, and outputs two types of ignition control signals for each cylinder.