JPH0439416Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a capacitor discharge type ignition device for an internal combustion engine.

[Prior art] As a capacitor discharge type ignition device for an internal combustion engine, a high voltage for charging a capacitor is obtained by intermittent current flowing from a battery through a voltage induction coil without using an exciter coil. There is something.

This type of ignition device has an ignition coil, an ignition energy storage capacitor provided on the primary side of the ignition coil, and when conductive, the charge in the ignition energy storage capacitor is discharged to the primary coil of the ignition coil. It is equipped with a discharge control thyristor installed in the battery and a voltage induction coil, and by cutting off the current flowing from the battery through the voltage induction coil, the voltage induced in the coil is used to store ignition energy through the capacitor charging diode. I am trying to charge the capacitor for this purpose.

As a conventional ignition device of this type,
The one shown in No. 137884 is known. In this ignition system, the discharge control switch that discharges the ignition energy storage capacitor also serves as a switch means that controls the current flowing through the voltage induction coil, and when the discharge control switch is conductive, it discharges the charge in the ignition energy storage capacitor. The primary coil of the ignition coil is discharged to perform an ignition operation, and current is caused to flow from the battery to the voltage induction coil. When the discharge control switch is turned on, the ignition energy storage capacitor is discharged and ignition is performed, and then when the discharge control switch is cut off, a high voltage is induced in the voltage induction coil, and this voltage is used to store the ignition energy. Charge the capacitor.

[Problems to be solved by the invention] In the conventional capacitor discharge type internal combustion engine ignition system that charges the ignition energy storage capacitor using the induced voltage of the voltage induction coil, the discharge control switch interrupts the current flowing through the voltage induction coil. Since the ignition coil also served as a switch for ignition, voltage was only induced in the voltage induction coil immediately after the ignition operation, and the ignition energy storage capacitor was charged only once per ignition cycle. Therefore, in order to store sufficient energy in the ignition energy storage capacitor, it is necessary to use a large voltage induction coil with a large number of turns, and there is a problem that it is necessary to use a large and expensive voltage induction coil. Ta. In addition, in order to increase the induced voltage in the voltage induction coil, it is necessary to increase the current flowing through the voltage induction coil, which not only increases the loss but also requires a large capacity as a switch element to intermittent the current in the voltage induction coil. There was a problem in that the equipment needed to be used was expensive.

The purpose of this invention is to discharge the electric charge of the ignition energy storage capacitor to the primary coil of the ignition coil when electrical conduction occurs between the ignition coil and the ignition energy storage capacitor provided on the primary side of the ignition coil. A discharge control thyristor provided,
In a capacitor discharge type ignition device for an internal combustion engine, which is equipped with a voltage induction coil and charges an ignition energy storage capacitor through a capacitor charging diode with a voltage induced in the coil by interrupting the current flowing through the voltage induction coil, In addition to increasing the number of times the ignition energy storage capacitor is charged per ignition cycle to increase the energy stored in the ignition energy storage capacitor,
The purpose of this invention is to set the current flowing through the voltage induction coil lower than before to reduce loss, and to enable the use of a switch with a small capacity for turning on and off the current flowing through the voltage induction coil.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a transistor switch provided to turn on and off the current flowing through the voltage induction coil, and a transistor switch that detects the current flowing through the voltage induction coil. a current detection circuit;
The timer capacitor is charged at a constant time constant from the power supply, and the discharge circuit that discharges the charge of the timer capacitor when the current detection value detected by the current detection circuit reaches the set value, and the terminal voltage of the timer capacitor is set to the set value. A comparison circuit for command signal output generates a cutoff command signal when the terminal voltage of the timer capacitor is less than the set value and generates a conduction command signal when the terminal voltage of the timer capacitor exceeds the set value. a switching stop circuit that outputs a switching stop signal during a period when a voltage higher than a predetermined threshold level is generated between the gate cathode of the discharge control thyristor; a cutoff time setting circuit and a switching stop circuit; Using the output of the circuit as input, when a conduction command signal or a switching stop signal is generated, a base current is gradually applied to the transistor switch to gradually turn the transistor switch on, and when a cutoff command signal is generated, the transistor switch is turned off. A switching control circuit is provided.

[Operation of the invention] As described above, if a transistor switch is provided separately from the discharge control switch and the transistor switch is used to turn on and off the current flowing through the voltage induction coil, the operation of the discharge control switch will be affected. The current flowing through the voltage induction coil is 1.
The ignition energy storage capacitor can be charged multiple times per ignition cycle because the voltage can be induced in the voltage induction coil multiple times per ignition cycle. Therefore, a large amount of energy can be stored in the ignition energy storage capacitor without making the induced voltage of the voltage induction coil very high, and a smaller voltage induction coil with fewer turns than before can be used. Furthermore, since the current flowing through the voltage induction coil can be made smaller than in the past, losses can be reduced, and an inexpensive switch element with a small capacity can be used as the switch element.

In addition, a cutoff time setting circuit as described above is provided,
By detecting the current flowing through the voltage induction coil and turning off the transistor switch to cut off the current flowing through the coil when the current reaches a set value, even if the power supply voltage changes, the cutoff current of the voltage induction coil can be reduced. Since the induced voltage can be kept constant by keeping the value constant, the charging voltage of the ignition energy storage capacitor can always be kept constant, and the ignition performance can be kept constant.

When a transistor switch is provided to turn on and off the current flowing through the voltage induction coil as described above, if the transistor switch is made conductive instantaneously, the ignition energy storage capacitor is disconnected from the capacitor charging diode during the recovery time of the capacitor charging diode. The rise of the discharge current flowing through the transistor switch becomes faster and the peak value of the discharge current becomes larger, so there is a risk of high voltage being induced on the secondary side of the ignition coil at times other than the ignition timing, causing sparks to fly. . In the present invention, in order to prevent such problems from occurring, the switching control circuit is configured to gradually apply base current to the transistor switch when the transistor switch is turned on. With this configuration, since the transistor switch gradually becomes conductive, it is possible to suppress the discharge current flowing from the ignition energy storage capacitor through the capacitor charging diode and the transistor switch during the recovery time of the capacitor charging diode. This eliminates the risk of erroneous ignition caused by high voltage being induced on the secondary side of the ignition coil at times other than the ignition timing.

Further, in the present invention, a switching stop signal is generated during a period when a voltage higher than a predetermined threshold level is generated between the gate and cathode of the discharge control thyristor, and the switching stop signal is applied to the switching control circuit. Since the transistor switch is maintained in a conductive state, it is possible to prevent a large current from flowing from the voltage induction coil side through the capacitor charging diode and the discharge control thyristor while the discharge control thyristor is conductive. Therefore, it is possible to use a capacitor charging diode and a discharge control thyristor having a small current capacity.

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

FIG. 1 shows the overall configuration of an embodiment of the present invention, in which 1 indicates the primary coil 1a and 2.
It is an ignition coil having a secondary coil 1b. One end of the primary coil 1a and the secondary coil 1b is grounded,
One end of an ignition energy storage capacitor 2 is connected to the non-grounded terminal of the primary coil 1a. A discharge control thyristor 3 with its cathode facing the ground is connected between the other end of the capacitor 2 and ground, and the thyristor 3 constitutes a discharge control switch. The other end of the capacitor 2 is also connected to the cathode of a capacitor charging diode 4, and the anode of the diode 4 is connected to one end of a voltage induction coil 5. A diode 6 with its cathode facing the ground side is connected to both ends of the primary coil 1a.
When a voltage is induced in the voltage induction coil 5, the capacitor 2 is charged through the diode 4, the capacitor 2, and the diode 6. Reference numeral 7 denotes an ignition timing control circuit which receives the output of the pulsar coil 8 as an input and outputs a trigger signal at a predetermined timing.The output of this ignition timing control circuit 7 is given to the gate of the thyristor 3. The capacitor 2, the thyristor 3, the diodes 4 and 6, and the ignition timing control circuit 7 constitute a primary current control circuit 9 that controls the primary current of the ignition coil. A spark plug 10 attached to a cylinder of an engine (not shown) is connected to the secondary coil of the ignition coil.

In order to turn on and off the voltage induction coil 5,
A transistor switch 11 is provided, and in order to control the transistor switch 11, a current detection circuit 12, a cutoff time setting circuit 13, a switching stop circuit 14, and a switching control circuit 15 are provided.

The current detection circuit 12 is a transistor switch 11
Detects the current flowing from the voltage induction coil 5 through the transistor switch 11 when the voltage induction coil 5 is in the on state.

The cutoff time setting circuit 13 includes a timer capacitor that is charged at a constant time constant from the power supply and a current detection circuit 1.
A discharge circuit that discharges the charge of the timer capacitor when the detected value of the current flowing current reaches the set value, and a discharge circuit that compares the terminal voltage of the timer capacitor with the set value and shuts off when the terminal voltage of the timer capacitor is less than the set value. It is composed of a command signal output comparison circuit that generates a command signal, and a command signal output comparison circuit that generates a conduction command signal when the terminal voltage of the timer capacitor is equal to or higher than a set value.

The switching stop circuit 14 detects the voltage between the gate and cathode of the discharge control thyristor and outputs a switching stop signal during a period when the voltage is equal to or higher than a predetermined threshold level.

The switching control circuit 15 inputs the outputs of the cutoff time setting circuit 13 and the switching stop circuit 14, and controls the transistor switch 11 when a conduction command signal or a switching stop signal is generated.
A base current is gradually applied to the transistor switch to gradually turn it on, and when a cutoff command signal is generated, the transistor switch is turned off.

Next, referring to FIG.
1, current detection circuit 12, cutoff time setting circuit 13,
A specific configuration example of the switching stop circuit 14 and the switching control circuit 15 will be explained.

The transistor switch 11 is composed of an NPN transistor Tr1, and the collector of the transistor Tr1 is connected to one end of the voltage induction coil 5.
A resistor R is connected between the emitter of transistor Tr1 and ground.
1 is connected, and the current detection circuit 1 is connected by the resistor R1.
2 are configured. The other end of the voltage induction coil 5 is connected to the positive terminal of a battery (not shown) whose negative terminal is grounded, and when the transistor Tr1 is turned on, the voltage induction coil 5 is connected to the battery (not shown) from the battery when the transistor Tr1 is turned on.
A current I1 flows through the transistor Tr1 and the resistor R1.

The cutoff time setting circuit 13 is connected to the comparison circuit CM1 and
It consists of CM2, resistors R2 to R6, and timer capacitor C1, and resistors R2, R4, and R5.
The terminal marked with a white circle is connected to the positive output terminal of a DC power supply circuit (not shown). The timer capacitor C1 is charged from the DC power supply circuit through the resistor R4 for a fixed number of hours. The comparison circuit CM1 compares the detection signal (voltage across the resistor R1) V1 of the conducting current detected by the current detection circuit 12 with the set voltage Vr1 obtained across the resistor R3. When the detection signal V1 of the conducting current becomes equal to or higher than the set voltage Vr1, the output stage of the comparator circuit CM1 is turned on and the charge in the timer capacitor C1 is discharged. That is, in this example, the comparison circuit CM1 and the resistors R2 and R3 constitute a discharge circuit that discharges the charge of the timer capacitor when the detected value of the current flowing through the voltage induction coil 5 reaches a set value.

The comparison circuit CM2 constitutes a command signal output comparison circuit, and this comparison circuit compares the terminal voltage V2 of the timer capacitor C1 with the set voltage Vr2 obtained across the resistor R6 and outputs the timer capacitor C1.
When the terminal voltage V2 of the timer capacitor C1 is less than the set voltage Vr2, a cutoff command signal (in this example, a high level signal) is generated, and when the terminal voltage V2 of the timer capacitor C1 exceeds the set voltage Vr2, a conduction command signal (in this example, a high level signal) is generated. (nearly ground level signal).

The switching stop circuit 14 includes a comparator circuit CM3 and resistors R7 and R8, and the terminal of the resistor R7 marked with a white circle is connected to the positive output terminal of a DC power supply (not shown). The gate-to-cathode voltage V3 of the thyristor 3 and the set voltage Vr3 obtained across the resistor R8 are input to the inverting input terminal and non-inverting input terminal of the comparator circuit CM3, respectively, and the gate-to-cathode voltage V3 of the thyristor 3 is applied to both ends of the resistor R8. When the set voltage (threshold level) obtained by the comparison circuit CM3 is equal to or higher than Vr3, the potential at the output terminal of the comparator circuit CM3 becomes zero (a switching stop signal is output).

The switching control circuit 15 includes a transistor Tr2 whose collector-emitter circuit is connected in parallel between the base of the transistor Tr1 and ground;
A capacitor C2 connected in parallel between the collector and emitter of the transistor Tr2, and a transistor
It consists of resistors R9 and R10, one end of which is connected to the base of Tr2 and the base of transistor Tr1, respectively, and the other ends of resistors R9 and R10 are connected to the positive output terminal of a DC power supply (not shown).
The base of transistor Tr2 is connected to comparator circuit CM2 and
It is connected to the output terminal of CM3 and is used as a comparison circuit.
When the potential of the output terminal of CM2 or the potential of the output terminal of the comparator circuit CM3 is zero (approximately ground potential), the transistor Tr2 is held off, and when the potentials of the output terminals of both comparators are both at a high level, the transistor Tr2 is held off. It's starting to turn on.

Next, the operation of the above embodiment will be explained. Figure 3 shows the signal waveforms of each part of the circuit in Figure 2. Figure 3a shows the waveform of the voltage V4 between the base and ground of the transistor Tr2, and Figure b shows the terminal voltage of the capacitor C2 (transistor Tr1 base ground voltage)
The waveform of V5 is shown. Further, Fig. 3c and d show the waveforms of the collector-to-ground voltage V6 of the transistor Tr1 and the charging current I2 of the ignition energy storage capacitor 2, respectively, and Fig. 3e and f respectively show the terminal voltage of the ignition energy storage capacitor 2 ( The waveforms of the voltage applied between the anode and cathode of the thyristor 3) V7 and the discharge current I3 of the capacitor 2 are shown, h and i in the figure respectively
gate-cathode voltage V3 and 2 of the ignition coil
The waveform of the next induced voltage V8 is shown.

In the above embodiment, immediately after the power is turned on, the voltage across the timer capacitor C1 is zero, so the potential at the output terminal of the comparison circuit CM2 of the cutoff time setting circuit 13 is at a high level (when the cutoff command signal is It has occurred). Further, since no trigger signal is initially applied to the thyristor 3 and the voltage V3 between the gate and cathode of the thyristor 3 is zero, the potential of the output terminal of the comparison circuit CM3 of the switching stop circuit 14 is also at a high level. Therefore, the transistor Tr2 of the switching control circuit 15 is in an on state, and the transistor Tr1 is in an off state.

Next, when the timer capacitor C1 is charged through the resistor R4 and the terminal voltage V2 of the capacitor C1 becomes equal to or higher than the reference voltage Vr2, the potential at the output terminal of the comparator circuit CM2 becomes zero level (a conduction command signal is output), and the transistor Tr2 becomes Becomes cut off.
At this time, a charging current flows into the capacitor C2 through the resistor R10, and a base current is gradually supplied to the transistor Tr1, so that the transistor Tr1 is gradually turned on. As a result, a current flows from a battery (not shown) through the voltage induction coil 5, the transistor Tr1, and the resistor R1. When the current 11 of the voltage induction coil 5 becomes sufficiently large, the terminal voltage (detection signal of the current) V1 of the resistor R1 becomes the set voltage.
When the voltage exceeds Vr1, the output terminal of the comparator circuit CM1 becomes grounded, and the charge in the capacitor C1 is discharged through the output stage of the comparator circuit CM1. Therefore, the potential at the output terminal of the comparator circuit CM2 becomes high level (a cutoff command signal is output), and the transistor Tr2
turns on, and transistor Tr1 turns off. As a result, the current flowing through the voltage induction coil 5 is cut off, so a high voltage is induced in the coil 5, and a voltage V6 is applied between the collector of the transistor Tr1 and the ground. This causes diode 4
and 6, the ignition energy storage capacitor 2 is charged to the polarity shown. . When a predetermined period of time has passed after the timer capacitor C1 is discharged, the terminal voltage of the timer capacitor C1 returns to the set voltage Vr.
2 or more, the potential of the output terminal of the comparator circuit CM2 becomes zero, turning off the transistor Tr2,
Turn on the transistor Tr1. As a result, the voltage induction coil 5 is energized. When this energizing current becomes sufficiently large and the voltage V1 across the resistor R1 exceeds the set value Vr1, the output terminal of the comparator circuit CM1 becomes grounded and the timer capacitor C1 is discharged. As a result, the potential of the output terminal of comparator circuit CM2 becomes high level, so transistor Tr2
turns on, and transistor Tr1 turns off. At this time, a voltage is induced in the voltage induction coil 5, and the ignition energy storage capacitor 2 is charged by the voltage. Thereafter, the transistor Tr1 is repeatedly turned on and off by the same operation, and the transistor Tr1 is turned on and off repeatedly.
Every time Tr1 is turned off, a voltage is induced in the voltage induction coil 5, and the ignition energy storage capacitor 2 is charged. Note that the time t2 for holding the transistor Tr1 in the off state is set to a length necessary and sufficient to charge the capacitor 2 with the induced voltage of the voltage induction coil 5.

When the ignition timing control circuit 7 eventually gives a trigger signal to the thyristor 3, the thyristor 3 becomes conductive.
When the thyristor 3 becomes conductive, the charge in the capacitor 2 is discharged through the thyristor 2 and the primary coil 1a of the ignition coil, and a high voltage V is applied to the secondary side of the ignition coil.
8 induces. Since this high voltage is applied to the ignition plug 10, a spark is generated in the ignition plug, and the engine is ignited.

When the thyristor 3 becomes conductive, a voltage V3 higher than a predetermined threshold level Vr3 is generated between its gate and cathode, and the voltage V3 reaches the threshold level.
Since the potential of the output terminal of the period comparison circuit CM3, which is higher than Vr3, becomes zero, the transistor Tr2
is turned off, and the transistor Tr1 is kept on. This state continues while the thyristor 3 is conducting, and current continues to flow through the voltage induction coil 5. Therefore, even if the comparison circuit CM2 of the cutoff time setting circuit outputs a cutoff command signal while the thyristor 3 is conducting, the voltage induction coil 5 does not induce voltage, and the voltage induction coil 5 does not induce voltage while the thyristor 3 is conducting. Large currents I2' and I3' from the coil 5 through the diode 4 and the thyristor 3 (Fig. 3e and g)
reference. ) will never flow. Therefore, it is possible to use diode 4 and thyristor 3 with small current capacity, and it is possible to reduce costs.

Also, at this time, the time available for commutation of the thyristor 3 is t1 shown in Fig. 3g, and the currents I2 and I
3 can be made longer than the time t1' available for commutation of the thyristor 3 when the current flows. Therefore, it is possible to increase the number of times a voltage is induced in the voltage induction coil 5 during one ignition cycle, thereby increasing the energy stored in the capacitor 2, and improving ignition performance.

When the thyristor 3 conducts as described above, the voltage induction coil 5 as shown by I1' in FIG.
The current continues to flow through the capacitor 2, and the current cut-off value when the current in the voltage induction coil is cut off for the first time after the thyristor 3 is cut off increases. Therefore, the energy stored in the capacitor 2 can be increased.

In addition, in the above device, the transistor Tr
1 is turned on, a discharge current flows through the path of capacitor 2 → diode 4 → transistor Tr1 → resistor R1 → primary coil 1a of ignition coil → capacitor 2 during the recovery time of diode 4. When transistor Tr1 turns on instantly, this discharge current rises quickly, so 2
A high voltage is induced in the next coil 1b. In particular, when the capacitor 2 is charged for the first time immediately after the thyristor 3 is cut off, a large charging current flows through the diode 4 as indicated by I2'' shown in FIG. The discharge current that flows during the time becomes considerably large. Therefore, at this time, if the transistor Tr1 turns on instantaneously, the discharge current I2b that flows during the recovery of the diode 4 becomes considerably large.At this time, the terminal voltage V7 of the capacitor 2 becomes V in Figure 3 f
As shown by 7', there is a possibility that a considerably high voltage V8' (see FIG. 3i) is induced in the secondary coil of the ignition coil, and that an incorrect spark occurs at a timing other than the ignition timing.

Furthermore, when controlling an internal combustion engine according to its rotational speed, the pulse voltage induced in the primary coil of the ignition coil at the regular ignition timing is often used to detect the speed of the internal combustion engine. If voltage is generated at a different time, a detection error will occur, making it impossible to perform control accurately.

In the present invention, the switching control circuit 15
When a conduction command signal is given to
Since the base current is gradually supplied to Tr1 to gradually turn on the transistor Tr1, it is possible to prevent a discharge current that rises quickly from flowing into the primary coil 1a during the recovery time of the diode 4. , it is possible to eliminate the possibility that an illegal spark will occur after a large charging current I2'' flows through the capacitor 2, or that the speed detection circuit that detects the speed of the engine based on the primary voltage of the ignition coil will malfunction.

[Effects of the invention] As described above, according to the invention, a transistor switch is provided separately from a switch for controlling discharge, and the current flowing through the voltage induction coil is turned on and off by the transistor switch. Regardless of the operation of the control switch, the current flowing through the voltage induction coil can be interrupted many times per ignition cycle to induce voltage in the voltage induction coil many times, and the ignition energy storage capacitor can be inserted many times per ignition cycle. Can be charged times. Therefore, it is possible to use a small voltage induction coil with a smaller number of turns than in the past and to store sufficient energy in the ignition energy storage capacitor. Furthermore, since the current flowing through the voltage induction coil can be made smaller than in the past, losses can be reduced, and an inexpensive switch element with a small capacity can be used as the switch element.

Furthermore, in the present invention, the current flowing through the voltage induction coil is detected and when the current flowing through the voltage induction coil reaches a set value, the transistor switch is turned off to cut off the current flowing through the coil, so even if the power supply voltage changes, the voltage induction will not occur. This has the advantage that the cut-off current value of the coil can be kept constant and its induced voltage can be kept constant, and that the charging voltage of the ignition energy storage capacitor can always be kept constant and the ignition performance can be kept constant.

In addition, when turning on the transistor switch, a base current is gradually given to the transistor switch so that the transistor switch is turned on gradually. Therefore, during the recovery time of the capacitor charging diode, ignition energy storage It is possible to suppress the discharge current flowing from the capacitor through the capacitor charging diode and transistor switch, and eliminate the risk of erroneous ignition caused by high voltage being induced on the secondary side of the ignition coil at times other than the ignition timing. can.

Furthermore, in the present invention, a switching stop signal is generated during a period when a voltage higher than a predetermined threshold level is generated between the gate and cathode of the discharge control thyristor, and the switching stop signal is applied to the switching control circuit. Since the transistor switch is kept conductive, it is possible to prevent a large current from flowing from the voltage induction coil side through the capacitor charging diode and the discharge control thyristor while the discharge control thyristor is conductive. A diode for charging and a thyristor for controlling discharge that have a small current capacity can be used.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention.
FIG. 2 is a circuit diagram showing an embodiment in which each part of FIG. 1 is made more specific, and FIG. 3 is a waveform diagram showing signal waveforms of each part of FIG. 2. 1... Ignition coil, 2... Capacitor for ignition energy storage, 3... Thyristor for discharge control, 4
... Capacitor charging diode, 5 ... Voltage induction coil, 11 ... Transistor switch, 12
... Current detection circuit, 13 ... Cutoff time setting circuit.

Claims (1)

[Claims for Utility Model Registration] When an ignition coil and an ignition energy storage capacitor provided on the primary side of the ignition coil are electrically connected, the electric charge of the ignition energy storage capacitor is transferred to the primary coil of the ignition coil. The ignition energy is stored through the capacitor charging diode with the voltage induced in the coil by cutting off the current flowing through the voltage induction coil. A capacitor discharge type internal combustion engine ignition device that charges a capacitor for internal combustion engines, the transistor switch being provided to turn on and off the current flowing through the voltage induction coil, the current detection circuit detecting the current flowing through the voltage induction coil, A timer capacitor that is charged from a power supply at a constant time constant, a discharge circuit that discharges the charge of the timer capacitor when the current detection value detected by the current detection circuit reaches a set value, and a terminal voltage of the timer capacitor. A command signal output comparison that generates a cutoff command signal when the terminal voltage of the timer capacitor is less than the set value compared to the set value, and generates a conduction command signal when the terminal voltage of the timer capacitor exceeds the set value. a switching stop circuit that outputs a switching stop signal during a period when a voltage equal to or higher than a predetermined threshold level is generated between the gate cathode of the discharge control thyristor; Using the outputs of the setting circuit and the switching stop circuit as inputs, when the conduction command signal or the switching stop signal is generated, a base current is gradually passed through the transistor switch to gradually turn the transistor switch on, and the cutoff command signal is generated. A capacitor discharge type ignition device for an internal combustion engine, comprising a switching control circuit that turns off the transistor switch when the transistor switch is turned off.