JPS61283766A - Ignitor for internal-combustion engine - Google Patents

Abstract

PURPOSE:To simplify the circuit constitution by outputting an ignition signal at the time point when the first integration voltage having the wave form which increases by a certain voltage at the max. advance position and increases reaches the second integration voltage having the wave form which increases by a certain value at the min. advance position and lowers a little later. CONSTITUTION:A signal coil 5 generates the first and the second signals VS1 and VS2 which become the prescribed threshold values or more at the max. advance position and the min. advance position, and the integration operation for increasing the signal VS1 at a prescribed gradient is performed by the first integration circuit 6a, and the integration operation for lowering the signal VS2 at a prescribed gradient by the second integration circuit 6b is performed. When the terminal voltage V3 of the first integration condenser C4 reaches the terminal voltage V3 of the second integration condenser C6, an ignition signal V7 is generated from a signal output circuit 6d, and ignition operation is carried out through the primary current control circuit 3. Therefore, the need of installing a control circuit for controlling the ignition timing between the max. and min. advance positions in a signal output circuit is avoided, and the circuit constitution is made simple.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ignition device for an internal combustion engine that can retard ignition timing in accordance with an increase in the rotational speed of the engine.

[Summary of the Invention] The present invention provides a first integrated voltage that instantaneously increases by 1 to a constant voltage at the maximum advance position of an internal combustion engine, and then increases at a predetermined gradient, and a first integral voltage that instantaneously increases to a constant voltage at the minimum advance position. A second integral voltage that rises to a voltage of To obtain retard characteristics with a simple circuit configuration by comparing the integrated voltage and generating an ignition signal for determining the ignition timing when the first integrated voltage reaches the second integrated voltage. The present invention provides an ignition device for an internal combustion engine that enables the following.

[Prior Art] Depending on the internal combustion engine, it is often necessary to retard the ignition timing in a predetermined rotational speed range.

For example, in a two-stroke engine, by retarding the ignition timing when the engine is running at high speed, it is possible to suppress a decrease in engine output at high speeds.

Additionally, in order to prevent the engine from overspeeding, it may be necessary to retard the ignition timing at high speeds.

Generally, an ignition device for an internal combustion engine includes an ignition coil, and a primary current control circuit that controls the primary current of the ignition coil by operating a semiconductor switch to induce a high voltage for ignition in a secondary coil of the ignition coil. It is equipped with an ignition signal generation circuit that generates an ignition signal that operates a semiconductor switch at the ignition timing of an internal combustion engine, and by operating the semiconductor switch with the ignition signal, the primary current of the ignition coil is suddenly changed and the ignition coil is activated. A high voltage for ignition is induced in the secondary coil. Therefore, in this type of ignition device, the ignition timing of the engine can be controlled by controlling the phase in which the signal generation circuit generates the ignition signal.

Incidentally, recently there has been a tendency to require accurate control of ignition timing. For example, when retarding the ignition timing when the engine speeds up, the retardation starting rotation speed (rpm)
It is necessary to accurately control the ignition timing so that the retard width, the slope of the retard characteristic, etc. have predetermined values. For this reason, electronically controlled signal generating circuits using an integrating circuit and a comparing circuit have come to be widely used as signal generating circuits.

Problem 1 to be Solved by the Invention When obtaining a retard characteristic with a conventional internal combustion 111m ignition system using an integral circuit, as shown in FIG. Obtain an integral voltage VC that rises at a first gradient to the maximum advance position θ1, and rises from the maximum advance position θ1 to the minimum advance position θ2 at a second gradient that is larger than the first slope, and obtain this integral voltage VC. is compared with the reference voltage ■r, and when the integrated voltage VC exceeds the reference voltage ■r, an ignition signal is generated. In this way, the integral voltage VC
When compared with the reference voltage ■r, as the rotational speed of the engine changes from low speed to high speed in the order of N1 → N2 → N3, the waveform of the integrated voltage yc with respect to the angle θ becomes as shown by the broken line, solid line, and chain line in Fig. 7. Therefore, the position at which the integrated voltage Vc reaches the reference voltage vr lags toward the top dead center TDC as in θi°→θ11→θ12. However, in this case, at low engine speed N1, the position θi° where the integral voltage Vc reaches the reference voltage ■' is ahead of the maximum advance position θ1. If the signals obtained by comparison are used as ignition signals, the ignition timing will advance to a position that is further advanced than the maximum allowable advance position at low speeds, making it impossible to operate the engine normally. However, it was necessary to install a circuit in the signal output circuit to limit the ignition timing between the maximum advance position and the minimum advance position, resulting in a complicated circuit configuration. .

An object of the present invention is to provide an ignition device for an internal combustion engine that can obtain retard characteristics with a simple circuit configuration.

[Means for solving the problems] As seen in FIG. 1 showing an embodiment of the present invention,
An ignition coil 2, a primary current control circuit 3 that controls the primary N current of the ignition coil 2 by operating the semiconductor switch 3C to induce a high voltage for ignition in the secondary coil 2b of the ignition coil, and an internal combustion i Maximum advance angle position θ1 and minimum advance angle position θ of the leap
2, respectively, the first level that becomes equal to or higher than the threshold level Vt.
and a signal generating means 5 that generates second signals VS1 and Vs2, and an ignition signal generating circuit 6 that receives the first and second signals as input and generates an ignition signal that operates the semiconductor switch 3C at the ignition timing of the internal combustion engine. The ignition device for an internal combustion engine is characterized in that the ignition signal generation circuit 6 is configured as shown below.

That is, the signal generating circuit 6 used in the present invention generates the first signal V
At the maximum advance position where S1 becomes equal to or higher than the threshold level Vt, the first integrating capacitor C4 is charged instantaneously, and the second integrating capacitor C4 is charged instantly.
a first integrating circuit that performs an integrating operation of charging the first integrating capacitor C4 until the signal VS2 reaches a threshold level Vt or higher and increasing the terminal voltage V3 of the first integrating capacitor at a predetermined slope; 6a and the second signal Vs2
A reset circuit 6c discharges the first integrating capacitor C4 when the signal Vs2 exceeds the threshold level, and instantaneously charges the second integrating capacitor C6 when the second signal Vs2 exceeds the threshold level. Integration for discharging the second integrating capacitor C6 with a predetermined discharge N current from the point where the second signal becomes less than the threshold level until the second signal VS2 becomes equal to or higher than the threshold level again. The second integrating circuit 6b that operates compares the terminal voltage of the first integrating capacitor C4 and the terminal voltage of the second integrating capacitor C6, and determines that the terminal voltage v3 of the first integrating capacitor C4 is equal to the second integrating capacitor C4. Terminal voltage V4 of capacitor c6
and a signal output circuit that generates an ignition signal v7 when the ignition signal V7 is reached.

[Operation of the invention] With the above configuration, in the rotation range below the retard start rotation speed, the first integral voltage rises at the maximum advance position and at the same time the first integral voltage becomes the second integral voltage. As a result, the first integrated voltage will never exceed the second integrated voltage at a position advanced beyond the maximum advanced angle position. Therefore, in the rotation range below the retardation starting rotation speed, the first integrated voltage and the 12 integrated voltages are compared, and the ignition signal is generated when the first integrated voltage exceeds the second integrated voltage. There is also no possibility that an ignition signal will be generated at a position advanced beyond the maximum advanced angle position.

Therefore, there is no need to provide the signal output circuit with a control circuit for limiting the ignition timing between the maximum advance position and the minimum advance position, and the circuit configuration can be simplified.

[Example] The present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the present invention, in which 1 is an exciter coil arranged in a magnet generator driven by an internal combustion engine, 2 is a primary coil 2a whose one end is grounded; The ignition coil with the secondary coil 2b, 3 is the primary i! which controls the primary current of the ignition coil 2! This is a flow control circuit. The primary current control circuit 3 shown in this example is a capacitor discharge type circuit, and includes a diode 3a whose anode is connected to the non-grounded terminal of the exciter coil 1, and a diode 3a whose one end is connected to the cathode of the diode 3a and whose other end is a diode 3a. An ignition energy storage capacitor 3b is connected to the non-grounded terminal of the secondary coil 2a and charged to the polarity shown in the figure by the output of the exciter coil 1, and an ignition energy storage capacitor 3b is connected between one end of the capacitor 3b and the ground with its cathode facing the ground. A 1-nyristor 3C as a semiconductor switch for primary current control, a resistor 3d connected between the gate and cathode of the thyristor 3c, and a primary coil 2a.
It consists of a diode 3e connected to both ends of the ignition coil 2 with its cathode facing the ground side, and a secondary coil 2 of the ignition coil 2.
A spark plug 7 is connected to b.

This primary current control circuit 3 is known as a capacitor discharge type circuit, and therefore, the electric charge of the capacitor 3b is discharged to the primary coil 2a by conduction of the thyristor 3c, and a point Okawa is discharged to the secondary coil 2b of the ignition coil. A high voltage is induced, and the high voltage is applied to the spark plug 7 to generate an ignition spark. That is, in this ignition device, the conduction timing of the thyristor (primary current control semiconductor switch>30) is the ignition timing.

4 is a power supply circuit that rectifies and smoothes the output of the exciter coil 1 and outputs a DC voltage.
a and a resistor 4b, a power supply capacitor 4C that is charged by the output of the exciter coil 1 through a diode 4a and a resistor 4b, and a Zener diode 4d that limits the voltage across the capacitor 4C to a constant value.

Reference numeral 5 denotes a signal coil serving as a signal generating means disposed in a signal generator that rotates in synchronization with the internal combustion engine. The first to exceed Vt
A signal VS1 and a second signal Vs2 are generated. In addition,
In this specification and FIG. 5 of the drawings, the symbols shown at each rotation angle position (with a predetermined suffix attached to θ) indicate the angle advanced from the engine top dead center TDC to each position. It shows. In this example, as shown in FIG. 5(a), the first
The signal Vsl consists of a negative polarity signal, and the second signal Vs
2 consists of a positive polarity signal.

Reference numeral 6 denotes an ignition signal generation circuit that receives the first and second signals Vs1 and Vs, 2 as input and generates an ignition signal that operates the thyristor 3C as a semiconductor switch at the ignition timing of the internal combustion engine. are a first integration circuit 6a, a second integration circuit 6b, a reset circuit 6C,
It consists of a signal output circuit 6d.

The first integrating circuit 6a outputs the first signal S1 of negative polarity output from the signal coil 5 at the maximum advance angle position @(minimum retard position)
When the threshold value Vt is exceeded at θ1, a base current is applied to the transistor T1 through the parallel circuit of the capacitor C2 and the resistor R2, and the transistor T1 becomes conductive. When the transistor T1 becomes conductive, the base current is applied through the resistor R3. When the transistor T2 becomes conductive, the output voltage of the power supply circuit 4 (the capacitor 4
Voltage across C) El passes through transistor T2 and charges the charging power supply capacitor C3, and the capacitor C
3, a series circuit of resistors R4 and R5 connected in parallel to both ends of the transistor T3, a transistor T3 which is turned on by supplying a base current through the resistor R4, and an output voltage E1 of the power supply circuit through the transistor T2 and the transistor T3 when the transistor T3 is turned on. Voltage E divided by resistors R4 and R5
2 (<El), and a first integrating capacitor C4, which is charged instantaneously to 2 (<El) and is additionally charged via a resistor R6 with the terminal voltage of the capacitor C3.

The second integrating circuit 6b is configured such that the second signal Vs2 of positive polarity output from the signal coil 5 is at the minimum advance angle position (maximum retardation position) θ.
2, when the threshold value reaches Vt or higher, the resistance R
A base current is supplied through the parallel circuit of 7 and capacitor C5 and diode D4, and the capacitor c3
A collector current is applied through the diode D5 due to the residual charge of the transistor T4, and the transistor T4 becomes conductive.
The transistor T5 is turned on by supplying a base current through the resistor R8 due to the conduction of the transistor T5, and the second transistor T5 is charged to approximately the output voltage E1 of the power supply circuit 4 through the transistor T5.
and a resistor R9 which is connected in parallel to the capacitor C6 and constitutes a discharge circuit that discharges the charge of the capacitor at a constant time constant.

Also in this embodiment, diode D5 and transistor T4 constitute a reset circuit that discharges capacitors C3 and C4 when second signal Vs2 is generated.

The signal output circuit 6d includes a programmable unijunction transistor (hereinafter referred to as JT) Pl and a resistor R.
It consists of IO and R11. The anode of PUT is connected to the non-grounded terminal of the first integrating capacitor C4,
The gate is connected to the second integrating capacitor C6 via the resistor R10.
connected to the non-grounded terminal of the Then, the cathode of PUT is connected to the gate (
When PUT Pl is conductive, an ignition signal v7 is applied to the thyristor 3C so that the thyristor 3C becomes conductive (ignition operation is performed).

Next, the operation of the above embodiment will be explained. When the first signal VS1 becomes equal to or higher than the threshold level at the maximum advance angle position nθ1, the transistor T1 and the transistor T2 become conductive, and the capacitor C3 is charged to approximately the output voltage E1 of the power supply circuit 4 with the illustrated polarity.

The waveform of the terminal voltage (2) of the capacitor C3 is as shown in FIG. 5(b). Also, at this time, the transistor T3 becomes conductive, so at the maximum advance angle position θ1, the first integrating capacitor C4 becomes
The capacitor C3 is instantly charged to a voltage E2 obtained by dividing the terminal voltage E1 of the capacitor C3 by resistors R4 and R5. When the first signal Vs1 falls below a threshold level, transistors T1 and T2 turn off. first integrating capacitor C
4 is charged to the voltage E1, the transistor T3 is in the cut-off state, and the first integrating capacitor C4 is charged to the voltage E1.
3 is charged to the polarity shown in the figure through the resistor R6 at a constant time constant.

The waveform of the terminal voltage (first integral voltage) V3 of the first integrating capacitor C4 in the rotation range below the set rotation speed where the ignition timing retardation starts is as shown by the solid line in FIG. 5(g). , and the first in the rotation range where the ignition timing is retarded.
The waveform of the integrated voltage v3 is as shown in FIG. 5(C). Further, the waveform of the first integrated voltage (3) in the rotation range where the ignition timing becomes constant after the retard is completed is as shown by the broken line in FIG. 5(g).

Next, when the second signal Vs2 becomes equal to or higher than the threshold level at the minimum advance angle position θ2, the transistor T4 becomes conductive, instantly discharging the capacitor C3, and discharging the first integrating capacitor C4 through the resistor R6. Furthermore, the conduction of the transistor T4 causes the transistor T5 to conduct, so that the capacitor C6 is instantaneously charged to approximately m voltage E1. When the second signal Vs2 falls below the threshold level, the transistor T4 is cut off and the transistor T5 is cut off, so that the second integrating capacitor C6 stops charging and the second integrating capacitor C6 is connected through the resistor R9. Discharges with a fixed time constant. The waveform of the terminal voltage (second integral voltage) V4 of the second integral capacitor C6 in the rotation range where the ignition timing is retarded is as shown in FIG. 5(C).

In addition, the second
The waveform of the second integrated voltage v4 is as shown by the broken line in FIG. 5(q), and the waveform of the second integrated voltage v4 in the rotation range after the ignition timing retard has stopped is as shown in FIG. The result is as shown by the solid line in (9).

Assuming that the engine is rotating at a rotation speed lower than the retard starting rotation speed, the first integral voltage V3 reaches the second integral voltage at the maximum advance position θ1, as shown by the broken line in FIG. 5(Q). In order to reach the voltage V4, the anode voltage of PUT Pl becomes equal to or higher than the gate voltage at the maximum advance position, the PtJT becomes conductive, and a trigger signal is given to the thyristor 3c. Therefore, in the rotation range below the retardation start rotation speed, ignition is performed at the maximum advance angle position θ1.

When the engine speed reaches the retard angle starting speed N1 or higher and enters the retard area, the first integral is applied at a position θd delayed from the maximum advance position θ1 (as shown in Fig. 5(C)). Since the voltage V3 reaches the second integrated voltage V4, pu
'r pi's anode voltage becomes higher than the gate voltage,
The PUT becomes conductive and a trigger signal is given to the thyristor 3C. Therefore, in the retard angle region, ignition is performed at a position θd delayed from the maximum advance angle position θ1. As the engine speed increases, the discharge time of the capacitor C6 becomes shorter, so the second integral voltage ■4 becomes higher, and the first integral voltage ■3 becomes the second integral voltage v3. The phase that reaches it is delayed. Therefore, the ignition timing is retarded as the rotational speed increases.

When the engine speed increases to the retardation end speed N2, the first integral voltage ■3 reaches the second integral voltage ■4 at the minimum advance position θ2, as shown in FIG. 5(g). Thus, the ignition operation is performed at this minimum advance angle position θ2. In the rotation range equal to or higher than the retardation end rotation speed, the first integral voltage v3 always changes to the second integral voltage v at the minimum advance angle position θ2.
4, the ignition timing will not be further delayed than the minimum advance position. Note that in the above embodiment, the second signal VS2
Therefore, so that the ignition signal is supplied to the cyrisk 3c through the diode [ ] 76 at the minimum advance angle position θ2,
Therefore, after the ignition timing is retarded to the minimum advance position, the second signal Vs2 provides an ignition signal to the thyristor 3C. Therefore, the characteristic of the engine ignition timing θi with respect to the rotational speed N (rpm) is as shown in FIG.

In the above embodiment, the capacitances of capacitors C3, 04, and C6 are each represented by the same sign, and the engine speed is set from the position θ3 where the N1 second signal VS2 is less than the threshold level to the next maximum. α is the angle to the advance position θ1, β is the angle from the maximum advance position θ1 to the ignition timing (the position where the first integral voltage 3 reaches the second integral voltage v4) (see Fig. 5 d), Charging capacitor C4 11
Assuming that the current I3 is the current and the N'Ili current flowing into the capacitor C6 is 6, the first integrated voltage v3 and the second integrated voltage 4 obtained across the first integrating capacitor C4 are V3 =
E2 + (13α)/ (6NC6)...(1)V
4 = 61 - (16 (α - + 13) / (6NC6
))... (2) Since the ignition operation is performed when the ignition timing becomes V3-V4, in the above two equations, if we set V3 = V4 and find β, we get β-((C3CB)/( I3 CB + 1603)
) X(6N (El -E2)-(I6 /C6)α
)...(3) Here, when N=N1, if we set β=0, then 6 (El
-E2)-(α/N1) (I6/C6)...(4
) Substituting equation (4) into equation (3) to find β, β= (
I6 C3)/(I306 + 1603)xα((
N/N1)-1) ...(5) Also, from equation (4),
The retard starting rotation speed N1 is N1-(θ1 16)/(6
06(El −E2) )...(6) Therefore, by reducing the resistance R9, the second integrating capacitor C
When the charging current I6 of No. 6 is increased, the retardation starting rotation speed N1
becomes high, and when the resistance R6 is made small and the charge of the first integral capacitor C4 is increased, the slope of the retard angle gradually becomes force 1.

In the above embodiment, the first signal Vs1 was of negative polarity and the second signal VS2 was of positive polarity.
A similar circuit can be constructed even if S1 is of positive polarity and the second signal VS2 is of negative polarity.

In the above embodiment, the first integrating capacitor C4 is charged through the resistor R6, but the capacitor C4 may be charged through a constant current circuit.

Alternatively, the second integrating capacitor C6 may be discharged through a constant current circuit.

Furthermore, in the above embodiment, the transistor T4 of the second integrating circuit 6b also serves as the transistor of the reset circuit 6C, but it is also possible to provide a separate reset circuit without using the elements of the second integrating circuit. .

In the above embodiment, a PUT is used as a comparison circuit constituting the signal output circuit, but the signal output circuit can also be constructed using a normal voltage comparator.

In the above embodiment, when the first signal becomes equal to or higher than the threshold level, the charging power supply capacitor C3 is charged instantaneously, and the first integrating capacitor C4 is charged with the terminal voltage of the capacitor C3. However, the first signal VS1
A flip-flop circuit is provided which is triggered when the second signal Vs2 exceeds the threshold level and is reset when the second signal Vs2 exceeds the threshold level. A rectangular wave voltage is obtained, and the rectangular wave voltage causes the first integrating capacitor C4 to
You may also charge the battery.

As in the above embodiment, the first integrated voltage ■3 has a waveform that rises to a constant voltage at the maximum advance position and then rises at a constant slope, and rises to a constant voltage at the minimum advance position θ2. After that, obtain 12 integrated voltages with a waveform that descends at a constant slope from a position slightly delayed from the minimum advance angle position, compare both integrated voltages, and compare the first integrated voltage with the second integrated voltage. If the ignition signal is output when the ignition signal is reached, the position where the condition for generating the ignition signal is satisfied between the peak integral voltages will not advance beyond the maximum advance position in the rotation range below the retard start rotation speed. Therefore, there is no need to provide a control circuit in the signal output circuit to prevent the ignition timing from advancing beyond the maximum advance position in the rotation range below the retardation start rotation speed.
The configuration of the signal output circuit can be simplified.

The power supply circuit 4 used in the above embodiment may be the circuit shown in FIG. In this power supply circuit, exciter coil 1
With an output voltage of negative polarity (half cycle not contributing to the charging of capacitor 3, ie not contributing to the supply of ignition energy) capacitor 4q is charged to the polarity shown through diodes 40 and 4f. When capacitor 4g finishes charging, the charge of capacitor 4g is transferred to diode 4a.
through the capacitor 4c, and the capacitor 4C-
is charged to the polarity shown. The terminal voltage of this capacitor 4C is limited to a constant value E1 by a Zener diode 4d. The resistor 4h is for discharging the capacitor.

Further, in the above embodiment, the circuit shown in FIG. 3 can also be used as the power supply circuit. In this power supply circuit, the capacitor 4C is charged to the illustrated polarity through the diode 4a by the negative half-cycle output of the exciter coil 1. The terminal voltage of this capacitor 4C is the set value,
When the current is reached, the Zener diode 4d becomes conductive and supplies an ignition signal to the thyristor 4k.
The terminal voltage of the capacitor 41 is limited to a constant value E1.

In the above embodiment, the present invention was applied to an ignition device equipped with a capacitor discharge type primary current control circuit.
The present invention can also be applied to an ignition device using a current interrupt type primary current control circuit 3 as shown in the figure. In the ignition device shown in FIG. 4, when a positive half-cycle output is generated in the exciter coil 1, a base current flows to the transistor 39 through the primary coil 2a, and the transistor 3g becomes conductive. This causes a short circuit l! from exciter coil 1 through diode 3f and transistor 3q. The flow flows. Next, when an ignition signal is applied to the gate of the thyristor 3C as a semiconductor switch for controlling the primary current, the thyristor 3C becomes conductive and the transistor 3g is cut off. As a result, exciter coil 1
Since the current flowing through the ignition coil 2 is cut off, a high voltage is induced in the exciter coil, and this voltage is further boosted by the ignition coil 2 and applied to the ignition plug P. Therefore, in this ignition device as well, the ignition operation is performed when the thyristor 3C is conductive.

Note that elements other than thyristors can also be used as the primary current control semiconductor switch. For example, the thyristor 3C in FIG. 4 can be replaced with a transistor.

[Effects of the Invention] As described above, according to the present invention, the first integral voltage ■3 of the waveform that rises to a constant voltage at the maximum advance angle position θ1 and then rises at a constant slope, and the minimum advance angle After rising to a constant voltage at position θ2, a second integral voltage of a waveform that falls at a constant slope from a position slightly delayed from the minimum advance angle position is obtained, and the peak integral voltage is compared. Since the ignition signal is output when the first integrated voltage reaches the second integrated voltage, the ignition signal is output between the two integrated voltages at a position advanced from the maximum advance position in the rotation range below the retard start rotation speed. The conditions for generating a signal are never met.

Therefore, there is no need to provide the signal output circuit with a control circuit for limiting the ignition timing between the maximum advance angle position and the minimum advance angle position, so there is an advantage that the circuit configuration can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIGS. 2 and 3 are circuit diagrams showing different modifications of the power supply circuit used in the embodiment of FIG. 1, and FIG. 4 is a circuit diagram showing an embodiment of the present invention. 5 is a signal waveform diagram of each part to explain the operation of the embodiment of FIG. 1, and FIG. 6 is a circuit diagram showing another example of an ignition device to which the embodiment of FIG. FIG. 7 is a diagram illustrating the operation of a conventional electronically controlled ignition system. 1°°° exciter coil, 2... ignition coil, 3.
...Primary current control circuit, 4...Power supply circuit, 5...Signal coil, 6...Signal generation circuit, 6a...First integration circuit, 6b...Second integration circuit, 6C...Reset circuit, 6d...Signal output circuit, Vsl...First signal, Vs2...Second signal, V3...First integrated voltage, v4...Second signal Integral voltage. Figure 1

Claims (1)

[Scope of Claims] An ignition coil, a primary current control circuit that controls a primary current of the ignition coil through the operation of a semiconductor switch to induce a high voltage for ignition in a secondary coil of the ignition coil, and an internal combustion Signal generating means for generating first and second signals that are equal to or higher than a threshold level at a maximum advance position and a minimum advance position of the engine, respectively; and ignition of the internal combustion engine using the first and second signals as input. and an ignition signal generation circuit that generates an ignition signal to operate the semiconductor switch at a certain time, wherein the ignition signal generation circuit is configured to generate an ignition signal at a position where the first signal is equal to or higher than a threshold level. Instantly charges a first integrating capacitor, and further charges the first integrating capacitor until the second signal exceeds a threshold level, increasing the terminal voltage of the first integrating capacitor at a predetermined slope. a reset circuit that discharges the first integrating capacitor when the second signal exceeds the threshold level; and a reset circuit that discharges the first integrating capacitor when the second signal exceeds the threshold level. , the second integrating capacitor is charged instantaneously and the second integrating capacitor is charged instantly from the point where the second signal becomes below the threshold level until the second signal becomes above the threshold level again. A second integrating circuit performs an integral operation to discharge the capacitor with a predetermined discharge current, and a terminal voltage of the first integrating capacitor is determined by comparing the terminal voltage of the first integrating capacitor and the terminal voltage of the second integrating capacitor. An ignition device for an internal combustion engine, comprising: a signal output circuit that generates an ignition signal when the voltage reaches the terminal voltage of the second integrating capacitor.