JPH0229866B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention uses an exciter coil that induces an alternating current voltage in synchronization with the rotation of an internal combustion engine as a power source, and a signal that induces a signal in synchronization with the rotation of the engine. The present invention relates to an ignition device for an internal combustion engine that uses a coil as a signal source to generate a high voltage to be applied to a spark plug for engine ignition at the ignition timing of the engine by controlling the primary current of the ignition coil.

[Prior Art] In an ignition system for an internal combustion engine, it is necessary to control the ignition timing of the engine according to the engine rotation speed (rpm), and it is necessary to use an ignition system that has ignition characteristics that meet the requirements of the engine. It is necessary to prepare. Generally, the ignition timing is advanced as the engine speed increases, but in two-stroke engines, the engine speed is adjusted to the set value in order to improve the engine's high-speed characteristics. When this happens, it may be necessary to retard the ignition timing. Also, depending on the purpose of the engine, it may be necessary to prevent the engine speed from exceeding a set value. It is necessary to have an ignition characteristic that retards the ignition timing when the ignition timing is reached.

Conventional ignition devices that obtain such ignition characteristics,
The engine speed is detected, and when the engine speed reaches a set value, the generation timing of the ignition signal that determines the ignition timing is retarded.

[Problems to be Solved by the Invention] However, in conventional devices, the rotation speed was detected based on the output of an exciter coil that supplied ignition energy or the output of a signal coil that obtained an ignition signal. It is unavoidable that errors will occur in the detected rotational speed due to variations in the waveform due to variations in the gap between the rotor and stator of the installed generator, and attempts to avoid this will result in the circuit becoming complicated. The disadvantage was that the equipment was expensive.

[Object of the Invention] An object of the present invention is to provide an ignition device for an internal combustion engine that has a simple configuration and can perform accurate retarding operation without being affected by the waveform of a generator. .

[Means for solving the problem] The ignition device for an internal combustion engine to which the present invention is directed uses an exciter coil that induces an alternating current voltage in synchronization with the rotation of the internal combustion engine as an ignition power source, and an ignition signal is applied to a control signal input terminal. an ignition circuit that controls the primary current of an ignition coil to perform an ignition operation by a primary current control semiconductor switch that operates when the internal combustion engine is activated; and an ignition timing determining circuit that supplies the ignition signal to the primary current control semiconductor switch by inputting the output of a signal coil that sequentially induces polarity signals at predetermined angular intervals to determine the ignition timing. It is something.

In order to solve the problems of the conventional technology, the present invention provides that the ignition timing determining circuit includes: (a) a power supply circuit including a power supply capacitor charged to one polarity by the output of the exciter coil; a first supplying an ignition signal to the primary current control semiconductor switch according to the first polarity signal;
(c) an integrating circuit comprising an integrating capacitor and an integrating capacitor charging circuit that charges the integrating capacitor at a constant time constant using the signal of the first polarity; and (d) when electrical conduction occurs. a reset circuit comprising a reset semiconductor switch provided to discharge the integrating capacitor; and a reset trigger circuit that conducts the reset semiconductor switch in response to the second polarity signal; A terminal voltage of a signal bypassing semiconductor switch provided to bypass the ignition signal supplied from the signal supply circuit to the primary current controlling semiconductor switch from the primary current controlling semiconductor switch and the integrating capacitor. The signal bypass trigger circuit conducts the signal bypass conductor switch while the voltage exceeds the reference voltage, and the signal bypass semiconductor switch conducts to one polarity due to the electric charge of the power supply capacitor. When the signal supply capacitor to be charged and the signal bypass semiconductor switch change from a conductive state to a cutoff state, the electric charge of the signal supply capacitor causes the above-mentioned 1
and a second ignition signal supply circuit for supplying an ignition signal to the semiconductor switch for controlling the next current; Before the ignition signal supplied to the primary current control semiconductor switch through the first signal supply circuit reaches a level that triggers the primary current control semiconductor switch, the terminal voltage of the integrating capacitor exceeds the reference voltage. and (g) when the rotation speed of the engine exceeds a second set value that is larger than the first set value, the second set value
The discharging time constant of the integrating capacitor is set so that the terminal voltage of the integrating capacitor maintains a value equal to or higher than the reference voltage until the position where a signal of polarity is generated.

[Operation of the invention] In each of the above configurations, the basic operation of the ignition device is the same as that of the conventional device, and an ignition signal is sent from the ignition timing determining circuit to the semiconductor switch for primary current control of the ignition circuit at the ignition timing of the engine. When supplied, the primary current control semiconductor switch operates to control the primary current of the ignition coil and induce a high voltage for ignition in the secondary coil of the ignition coil. This generates a spark in the spark plug attached to the cylinder of the engine, igniting the engine.

In the ignition system of the present invention, the signal coil generates a first polarity signal Vs1 at an engine rotation angle θi1, and then generates a signal Vs1 at an angle θi2, as shown in FIG. 2B.
A signal Vs2 of the second polarity is generated. The peak values of these signals gradually increase as the engine speed increases from N1 to N2 to N3 to N4, as shown by the chain line in FIG. 2B. In this explanation, it is assumed that the width of each signal is sufficiently narrow, and for convenience, the position where each signal reaches its peak is referred to as the generation position of each signal.

When the signal of the first polarity rises, the integrating capacitor is charged by the signal, and the integrating capacitor is discharged at a constant time constant after the signal of the first polarity passes the peak. While the engine speed is low, the integration capacitor is completely discharged before the second polarity signal is generated, but when the engine speed increases to a certain extent, the integration capacitor is discharged as soon as the second polarity signal is generated. A charge remains. When a signal of the second polarity is generated, the reset circuit discharges the residual charge on the integrating capacitor, and the voltage at the terminals of the integrating capacitor becomes zero. Therefore, the terminal voltage Vc of the integrating capacitor has a waveform as shown in FIG. 2C.

On the other hand, in the power supply circuit, the power supply capacitor is charged by the output of the exciter coil, and the waveform of the terminal voltage Va becomes as shown in FIG. 2D, for example.

The terminal voltage of the integrating capacitor is input to the retard signal supply circuit, but when the engine speed is less than the first set value Ns1, the ignition signal supplied through the first signal supply circuit is input to the retard signal supply circuit. Since the terminal voltage of the integrating capacitor cannot rise above the reference voltage before reaching the level that triggers the control semiconductor switch, the signal bypass semiconductor switch is not conductive and the primary signal from the first signal supply circuit is Allows the ignition signal to be supplied to the current controlling semiconductor switch. Therefore, the first signal supply circuit supplies an ignition signal to the primary current control semiconductor switch when a signal of the first polarity is generated at an angle .theta.i1.
As a result, an ignition operation is performed, and the engine is ignited at the position θi1 where the first polarity signal is generated.

In contrast, the engine speed is the first set value Ns1
or above (for example, N2 in Fig. 2C), the terminal voltage Vc of the integrating capacitor will exceed the reference voltage Vz before the ignition signal applied through the first signal supply circuit reaches the trigger level of the semiconductor switch for primary current control. As a result, the signal bypass semiconductor switch of the retard signal supply circuit becomes conductive. Therefore, the ignition signal applied from the first signal supply circuit is bypassed through the signal bypass semiconductor switch, and no ignition operation is performed at the position where the signal of the first polarity is generated.
The signal bypass semiconductor switch is conductive while the terminal voltage of the integrating capacitor exceeds the reference voltage, and during this time the signal supply capacitor is charged with the charge of the power supply capacitor. When the terminal voltage of the integrating capacitor becomes lower than the reference voltage, the semiconductor switch for the signal bypass is cut off, so the second signal supply circuit is turned off.
An ignition signal is supplied to the semiconductor switch for controlling the next current, causing the ignition circuit to perform the ignition operation. Therefore, the ignition of the engine is performed at a position delayed from the position at which the first polarity signal is generated. The point at which the terminal voltage of the integral capacitor becomes lower than the reference voltage Vz is delayed as the engine speed increases (the integral capacitor cannot be discharged in time), so the engine ignition timing depends on the engine speed. It gradually lags behind as it rises.

When the engine speed exceeds the second set value Ns2 (>Ns1), the terminal voltage of the integrating capacitor exceeds the reference voltage until the integrating capacitor is reset by the second polarity signal. .
When such a state occurs, the integrating capacitor is reset by the signal of the second polarity, and when the semiconductor switch for the signal bypass is cut off in the process where the terminal voltage of the integrating capacitor becomes zero, the signal of the second polarity is reset. An ignition signal is supplied to the primary current control semiconductor switch at the location where the ignition signal is generated. Therefore, in the region where the engine speed is equal to or higher than the first set value Ns2, the ignition timing is constant, and the characteristic of the ignition timing θi with respect to the rotation speed N is as shown in FIG.

[Examples] Examples of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the present invention, in which 1 is an ignition coil having a primary coil 1a and a secondary coil 1b, and 2 is an ignition coil 1 attached to a cylinder of an engine (not shown). The spark plug is connected to the secondary coil of the One ends of the primary coil 1a and the secondary coil 1b are grounded, and one end of the ignition energy storage capacitor 3 is connected to the non-grounded terminal of the primary coil 1a. A discharge control thyristor 4 is connected between the other end of the capacitor 3 and the ground, with its cathode facing the ground, and the cathode of a diode 5 is connected to the connection point between the anode of the thyristor 4 and the capacitor 3. One end of the exciter coil 6 is connected to. The other end of the exciter coil 6 is a thyristor 4
A diode 7 with its anode facing the ground side is connected between the cathode of the diode 5 and the ground. A resistor 8 and a capacitor 9 are connected in parallel between the gate and cathode of the thyristor 4. The exciter coil 6 is provided in a magnet generator that rotates synchronously with the engine, and generates an alternating current voltage Ve in synchronization with the rotation of the engine as shown in FIG. 2A. The ignition circuit 10 is constituted by each of the above parts. Note that the horizontal axis in FIG. 2 indicates the rotation angle θ of the engine.

In the ignition circuit 10, the exciter coil 6, the diode 5, and the capacitor 3 constitute a power supply circuit that flows the primary current to the ignition coil 1, and the discharge control thyristor 4 suddenly changes the primary current of the ignition coil at the ignition timing. A semiconductor switch for controlling the primary current is configured. This ignition circuit is well known as a capacitor discharge type ignition circuit, and in this ignition circuit, the capacitor 3 is charged to the polarity shown by the half-cycle output of the exciter coil 6 in the direction of the arrow shown in the drawing. The waveform of the terminal voltage V3 of this capacitor 3 is as shown in FIG. 2E. Next, when an ignition signal (signal for determining the ignition timing) is supplied to the gate of the thyristor 4 from the ignition timing determination circuit described later, the thyristor 4
conducts, and the charge in the capacitor 3 is discharged through the thyristor 4 and the primary coil 1a of the ignition coil 1. Since this discharge occurs instantaneously, a large magnetic flux change occurs in the iron core of the ignition coil 1, and a high voltage for ignition is induced in the secondary coil 1b of the ignition coil. Since this high voltage is applied to the ignition plug 2, a spark is generated in the ignition plug and the engine is ignited.

The cathode of a diode 12 is connected to the gate of the thyristor 4 of the ignition circuit 10 via a resistor 11, and the anode of the diode 12 is connected via a resistor 13 to one end of a signal coil 14. The other end of the signal coil 14 is connected to the cathode (ground) of the thyristor 4. The signal coil 14 is
It is installed in a signal generator that rotates in synchronization with the rotation of the engine, and as shown in FIG.
A signal of polarity (in this example, a signal of negative polarity) Vs2 is sequentially generated. Here, the signal generator generates a signal Vs1 of a first polarity at an ignition timing θi1 in a rotation range below the set rotation speed of the engine, and generates a signal Vs1 of a second polarity.
Ignition timing θi2 (angle delayed from θi1 toward the top dead center of the engine) when Vs2 is the engine's set rotation speed or higher.
is configured to occur. This signal generator may be provided separately from the magnet generator provided with the exciter coil, or may be configured using a part of the rotor magnetic poles of the magnet generator. In this example, the signal coil 14, the resistors 11 and 13, and the diode 12 provide a second signal obtained from the signal coil 14.
A first signal supply circuit is configured to supply an ignition signal to the thyristor 4 according to a signal of polarity.

The anode of a diode 16 is connected to the non-grounded terminal of the exciter coil 6 via a resistor 15, and the cathode of the diode 16 is connected to one end of a power supply capacitor 17. The other end of power supply capacitor 17 is connected to the anode of diode 18, and the cathode of diode 18 is grounded. A Zener diode 19 with an anode facing the ground side is connected in parallel to both ends of the power supply capacitor 17, and a power supply circuit 20 is constituted by the resistor 15, diodes 16 and 18, the power supply capacitor 17, and the Zener diode 19. In this power supply circuit, the output of one half cycle of the exciter coil 6 charges the capacitor 17 to the Zener voltage of the Zener diode 19 with the characteristics shown. The waveform of the voltage Va across the capacitor 17 is as shown in FIG. 2D.

An anode of a diode 21 is connected to the non-grounded terminal of the signal coil 14, and an integrating capacitor 22 is connected between the cathode of the diode 21 and the ground. A resistor 2 is connected to both ends of the integrating capacitor 22.
3 are connected in parallel, and an integrating circuit 25 is constituted by a diode 21, a capacitor 22, and a resistor 23.

A diode 3 is connected to the ground terminal of the signal coil 14.
The anode of the diode 30 is connected to the anode of the diode 30, and one end of the capacitor 31 is connected to the cathode of the diode 30. The other end of the capacitor 31 is connected to the anode of a diode 33 via a resistor 32, and the cathode of the diode 33 is connected to the non-ground terminal of the signal coil 14. Also, capacitor 31 and resistor 3
A diode 34 with its anode facing the ground side is connected between the connection point with 2 and the ground. The base of a transistor 35 constituting a reset semiconductor switch whose emitter is grounded is connected to the diode 30 side terminal of the capacitor 31, and the collector of the transistor 35 is connected to the non-grounded terminal of the integrating capacitor 22. diode 30,
33, 34, resistor 32, capacitor 31, and transistor 35 constitute a reset circuit 36 that discharges the charge remaining in the integrating capacitor 22 when the second polarity signal Vs2 is generated. 30,3
3, 34, capacitor 31 and resistor 32,
A reset trigger circuit is configured to trigger the transistor 35 (reset semiconductor switch) when the second polarity signal Vs2 is generated. In this reset circuit, the signal coil 14
When the signal Vs2 of polarity is generated, the capacitor 31
is charged to the polarity shown, and when the charge on the capacitor 31 reaches a predetermined value, the transistor 35 is triggered to conduct. The conduction of the transistor 35 discharges the charge in the integrating capacitor 22 and resets the integrating circuit 25.

One non-grounded end of the integrating capacitor 22 is connected to the cathode of a Zener diode 40, and the anode of the Zener diode 40 is connected to the base of a transistor 41 constituting a semiconductor switch for signal bypass. The emitter of the transistor 41 is connected to the ground terminal of the power supply capacitor 17, and the collector is connected to the cathode of a diode 42 whose anode is connected to the cathode of the diode 12. The collector of the transistor 41 is connected to the cathode of a diode 43, and the anode of the diode 43 is connected to the cathode of a diode 44 whose anode is grounded. One end of a resistor 45 is also connected to the anode of the diode 43, and a signal supply capacitor 46 is connected between the other end of the resistor 45 and the non-grounded terminal of the power supply capacitor 17. One end of a resistor 47 is connected to a terminal of the capacitor 46 opposite to the resistor 45, and the cathode of the other end of the resistor 47 is connected to the resistor 11.
It is connected to the anode of a diode 48 which is connected to the cathode of the thyristor 4 through the thyristor 4 . Diodes 42-44, 48, Zener diode 4
0, a transistor 41, a capacitor 46, and resistors 45 and 47 constitute a retard signal supply circuit 50. In this circuit, a Zener diode 4
0, while the terminal voltage Vc of the integrating capacitor 22 exceeds the reference voltage Vz, the transistor 41
(signal bypass conductor switch) is configured, and includes a diode 44, resistors 45 and 47, a capacitor 46, and a diode 4.
A second ignition signal supply unit that supplies an ignition signal to the primary current control semiconductor switch (thyristor 4) using the electric charge of the signal supply capacitor 46 when the signal bypass semiconductor switch changes from a conductive state to a cutoff state due to 8 and 8. The circuit is configured. In this retard signal supply circuit 50, when the integrating capacitor 22 becomes equal to or higher than the reference voltage Vz (the Zener voltage of the Zener diode 40), the transistor 41 becomes conductive, and the signal is supplied from the signal coil 14 to the thyristor 4 through the diode 12. The ignition signal is bypassed from the thyristor. While the transistor 41 is conducting, the power supply capacitor 17 to the capacitor 46,
Resistor 45, diode 43 and transistor 41
The signal supply capacitor 46 is charged through the path of
The terminal voltage Vc of the integrating capacitor 22 is the reference voltage Vz
When the voltage becomes lower and the transistor 41 is cut off, the charge in the capacitor 46 is discharged through the resistor 47, the diode 48, the resistor 11, the gate cathode of the thyristor 4, the diode 44, and the resistor 45, and supplies an ignition signal to the thyristor 4. .

In the above ignition system, when the signal Vs1 of the first polarity is generated from the signal coil 14, the integrating capacitor 22 is charged by the signal, and after the signal of the first polarity passes the peak, the integrating capacitor 22 is charged with a constant value. Discharge with a time constant. While the engine speed is low, the discharge of the integrating capacitor 22 is completed before the second polarity signal Vs2 is generated, but when the engine speed increases to a certain extent, the integration stops when the second polarity signal is generated. The capacitor 22 remains charged. When the second polarity signal Vs2 is generated, the transistor 35 of the reset circuit 36 becomes conductive, discharging the residual charge in the transistor integrating capacitor. Therefore, the engine speed is N1→N2→N3→N4
The terminal voltage of the integrating capacitor 22 when it changes to
Vc has a waveform as shown in FIG. 2C.

On the other hand, in the power supply circuit 20, the power supply capacitor 17 is charged by the output of the exciter coil 6, and the waveform of the terminal voltage Va becomes as shown in FIG. 2D.

The terminal voltage Vc of the integrating capacitor 22 is input to the retard signal supply circuit 50, but when the engine speed is less than the first set value Ns1, the signal coil 14
The terminal voltage Vc of the integrating capacitor 22 cannot exceed the reference voltage Vz before the ignition signal applied through the resistor 13, diode 12, and resistor 11 (through the first signal supply circuit) reaches a level that triggers the thyristor 4. Therefore, the transistor 41 does not become conductive and allows the ignition signal to be supplied from the signal coil 14 to the thyristor 4. Therefore, when the first polarity signal is generated at the angle θi1, an ignition signal is supplied to the thyristor 4, and the engine is ignited at the first polarity signal generation position θi1.

In contrast, the engine speed is the first set value Ns1
Above (for example, N2 in FIG. 2C), the ignition signal given from the signal coil 14 through the resistor 13, diode 12, and resistor 11 is transmitted to the thyristor 4.
Integrating capacitor 2 before reaching the trigger level of
The terminal voltage Vc of the second terminal becomes equal to or higher than the reference voltage Vz, and the transistor 41 of the retard signal supply circuit 50 becomes conductive. Therefore, the ignition signal supplied from the signal coil 14 through the diode 12 is transmitted to the transistor 41.
ignition operation is no longer performed at the position where the signal Vs1 of the first polarity is generated. The transistor 41 is conductive while the terminal voltage of the integrating capacitor 22 exceeds the reference voltage, and during this time the signal supply capacitor 46 is charged with the charge of the power supply capacitor 17. When the terminal voltage Vc of the integrating capacitor 22 becomes lower than the reference voltage Vz, the transistor 41
is cut off, signal supply capacitor 4
6 is discharged through the resistor 47, the diode 48, the resistor 11, the base cathode of the thyristor 4, the diode 44, and the resistor 45, and supplies the thyristor 4 with an ignition signal. Therefore, the ignition operation is performed when the terminal voltage Vc of the integrating capacitor 22 becomes lower than the reference voltage Vz. Terminal voltage of integrating capacitor 22
The point at which Vc becomes lower than the reference voltage Vz will be delayed as the engine speed increases (the integrating capacitor will not be able to discharge in time), so the engine ignition timing will change as the engine speed increases. Gradually it gets delayed.

When the engine speed exceeds the second set value Ns2 (>Ns1), for example, N4, the integral continues to the position θi2 where the integrating capacitor 22 is reset by the second polarity signal Vs2, as shown in FIG. 2C. The terminal voltage Vc of the capacitor is in a state exceeding the reference voltage Vz. When such a state occurs, when the transistor 41 is cut off in the process in which the integrating capacitor 22 is reset by the second polarity signal Vs2 and the terminal voltage of the integrating capacitor becomes zero (the second polarity signal Vs2 ignition signal is supplied to the thyristor 4 (at the occurrence position). Therefore, in the region where the engine speed is equal to or higher than the second set value Ns2, the ignition timing is constant, and the characteristic of the ignition timing θi with respect to the rotation speed N is as shown in FIG.

In the above embodiment, the first set rotation speed Ns1 at which the retard operation starts can be appropriately set by changing the reference voltage Vz, and the second set rotation speed Ns2 at which the retard operation ends By changing the discharge time constant of the integrating capacitor 22 as shown in FIG. 5, it is possible to set it appropriately as shown by Ns2a and Ns2b in FIG.

In the above embodiment, the integrating capacitor 22 is replaced by the resistor 2.
However, as shown in FIG. 3, the integrating capacitor 22 may be discharged with a constant current through a constant current circuit consisting of a transistor 51 and resistors 52 to 54.

[Effects of the Invention] As described above, according to the present invention, among the signals of the first and second polarities generated from the signal coil, the signal is charged by the signal of the first polarity that is generated first, and then the voltage is constant. A first integrating capacitor is provided which is discharged with a time constant of , and when a terminal voltage of the integrating capacitor is lower than a reference voltage, a first signal supply circuit supplies an ignition signal at a position where a signal of a first polarity is generated. and when the terminal voltage of the integrating capacitor exceeds the reference voltage, the first signal supply circuit is prevented from supplying the ignition signal while the terminal voltage of the integrating capacitor exceeds the reference voltage. Since the ignition timing is retarded, when the engine speed exceeds the first set value, the ignition timing is linearly retarded and the ignition timing remains constant at the engine speed above the second set value. ignition characteristics can be obtained. In the present invention, the set rotation speed is detected by comparing the terminal voltages of the integrating capacitors, so the set rotation speed can be accurately detected and accurate operation can be performed without being affected by the waveform of the generator. . In addition, the set rotational speed at which the retardation operation starts and the set rotational speed at which the retardation operation ends can be easily set to appropriate values by appropriately setting the reference voltage and the discharging time constant of the integrating capacitor. Circuit design can be facilitated.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing an embodiment of the present invention, Fig. 2 is a waveform diagram showing the operating waveforms of each part in Fig. 1 with respect to the rotation angle of the engine, and Fig. 3 is a modification of the integrating circuit. Fig. 4 is a diagram showing the ignition characteristics obtained by the embodiment shown in Fig. 1, and Fig. 5 shows the change in the terminal voltage waveform of the integrating capacitor when the discharging time constant of the integrating circuit is changed. FIG. 1...Ignition coil, 2...Spark plug, 3...
Capacitor, 4... Thyristor (semiconductor switch for primary current control), 5... Diode, 6... Exciter coil, 10... Ignition circuit, 11... Resistor, 12... Diode, 13... Resistor, 14...
...Signal coil, 16, 18...Diode, 17
... Power supply capacitor, 19 ... Zener diode, 20 ... Power supply circuit, 21 ... Diode, 2
2... Integrating capacitor, 23... Resistor, 25...
Integrating circuit, 30, 33, 34...diode, 3
1...Capacitor, 32...Resistor, 35...Transistor (semiconductor switch for reset), 36...
...Reset circuit, 40... Zener diode,
41... Transistor (semiconductor switch for signal bypass), 42 to 44, 48... Diode, 45...
...Resistor, 46...Signal supply capacitor.

Claims (1)

[Claims] 1. An ignition coil using an exciter coil that induces an alternating current voltage in synchronization with the rotation of an internal combustion engine as an ignition power source, and a semiconductor switch for primary current control that operates when an ignition signal is applied to a control signal input terminal. an ignition circuit that controls the primary current of the internal combustion engine to perform an ignition operation; and a signal that sequentially induces a first polarity signal and a second polarity signal at predetermined angular intervals in synchronization with the rotation of the internal combustion engine. 1 above using the output of the coil as input.
An ignition device for an internal combustion engine, comprising: an ignition timing determination circuit that supplies the ignition signal to a semiconductor switch for next current control to determine ignition timing, wherein the ignition timing determination circuit has one polarity at the output of the exciter coil a first signal supply circuit that supplies an ignition signal to the primary current control semiconductor switch based on the first polarity signal; an integrating capacitor and the first an integrating circuit having an integrating capacitor charging circuit that charges the integrating capacitor at a constant time constant according to a polarity signal; a reset semiconductor switch provided to discharge the integrating capacitor when conductive; and the second semiconductor switch. a reset trigger circuit that conducts the reset semiconductor switch in response to a polarity signal; and a reset trigger circuit that conducts the reset semiconductor switch in response to a polarity signal; A signal bypass semiconductor switch provided to bypass the current control semiconductor switch and a signal bypass conductor switch that conducts the signal bypass conductor switch while the terminal voltage of the integrating capacitor is equal to or higher than a reference voltage. While the trigger circuit and the semiconductor switch for signal bypass are electrically connected, the signal supply capacitor charged to one polarity by the electric charge of the power supply capacitor and the semiconductor switch for signal bypass switch from a conductive state to a cutoff state. and a second ignition signal supply circuit that supplies an ignition signal to the primary current control semiconductor switch using the electric charge of the signal supply capacitor when the rotational speed of the internal combustion engine increases. before the ignition signal supplied to the primary current control semiconductor switch through the first signal supply circuit reaches a level that triggers the primary current control semiconductor switch when The reference voltage is determined such that the terminal voltage of the integrating capacitor is equal to or higher than the reference voltage, and the rotation speed of the engine is set to be equal to or higher than the first reference voltage.
When discharging the integrating capacitor, the terminal voltage of the integrating capacitor is maintained at a value equal to or higher than the reference voltage until the second polarity signal is generated when the voltage reaches a second set value, which is larger than the set value of . An ignition device for an internal combustion engine, characterized in that a constant is set.