JP2003328914A - Ignition device for dc/dc converter type internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ignition device for a DC/DC converter type internal combustion engine wherein increasing a life of a circuit part by preventing a capacitor for ignition from being held for a long time in a state of charging being completed. <P>SOLUTION: A time needed for one rotation of an internal combustion engine is measured and by decreasing a time needed for charging a capacitor 4 for ignition to a predetermined target voltage from the measured time, a pressure rising operation stop time is computed. During a pressure rising operation stop time from a time when an ignition signal Vi is given to a switch 5 for discharge at an ignition timing, pressure rising operation of the DC/DC converter 2 is stopped and when measurement of the pressure rising operation stop time is completed, pressure rising operation of the DC/DC converter 2 is started to start charging of the capacitor 4 for ignition. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a capacitor discharge type DC using a DC / DC converter for boosting an output voltage of a battery as a power source for charging an ignition capacitor.
The present invention relates to an ignition device for a DC / DC converter type internal combustion engine.

[0002]

2. Description of the Related Art A capacitor discharge type DC / DC converter type ignition device for an internal combustion engine includes a step-up transformer to which a primary current is supplied from a battery and a chopper switch provided so as to turn on / off the primary current of the step-up transformer. A DC / DC converter for boosting the output voltage of the battery, which includes a switch control circuit for turning on and off the chopper switch, an ignition coil, and an output voltage of the DC / DC converter provided on the primary side of the ignition coil. An ignition capacitor charged to one polarity, a discharge switch provided so as to conduct when the ignition signal is given and discharge the electric charge accumulated in the ignition capacitor through the primary coil of the ignition coil, Ignition timing control unit and DC / DC for controlling timing of applying ignition signal to discharge switch
And a controller having a converter control unit for controlling the boosting operation of the converter. A thyristor is often used as the discharge switch.

In this type of ignition device, an ignition signal is given to the discharge switch at the ignition timing of the internal combustion engine to turn on the discharge switch to discharge the electric charge of the ignition capacitor through the primary coil of the ignition coil. The high voltage induced in the primary coil of the ignition coil when the discharge current flows is further increased by a step-up ratio determined by the turn ratio of the ignition coil to induce a high voltage for ignition in the secondary coil of the ignition coil.

When a thyristor is used as the discharge switch, the thyristor is turned on at ignition timing and then turned off for a certain period of time in order to turn it off.
It is necessary to prevent the forward voltage from being applied from the converter to the anode and cathode of the thyristor. Therefore, in the conventional ignition device of this type, at the same time as giving an ignition signal to the thyristor at the ignition timing, the step-up operation of the DC / DC converter is stopped and the length is set to a value necessary for turning off the thyristor. Immediately after the short rest period, the boost operation of the DC / DC converter is restarted,
The ignition capacitor was charged to the set voltage.

[0005]

As described above, DC /
In a conventional capacitor discharge type internal combustion engine ignition device using a DC converter as a power source for charging, the boosting operation of the converter is restarted immediately after the boosting operation of the converter is stopped only for a short rest period from the ignition timing. Since the ignition capacitor is charged up to the set voltage, the charging of the ignition capacitor is completed at a timing considerably before the next ignition timing after the boosting operation of the converter is restarted.

Therefore, in the conventional ignition device, the time for which the ignition capacitor is maintained in the fully charged state becomes long, and the high voltage (200V) across the ignition capacitor is increased.
Or 200 to several tens of V) is wastefully applied to the components of the ignition device such as the discharge switch for a long time.
There has been a problem that the load on the components of the ignition circuit is increased and the service life thereof is shortened.

An object of the present invention is to provide an ignition device for an internal combustion engine of a DC / DC converter type so that the ignition operation can be performed immediately after the ignition capacitor is charged to a predetermined target voltage, and ignition is performed. It is to prevent the high voltage from being unnecessarily applied to the components of the apparatus for a long time and to extend the life of the components of the ignition device.

[0008]

According to the present invention, a step-up transformer to which a primary current is supplied from a battery, a chopper switch provided so as to turn on / off the primary current of the step-up transformer, and a chopper switch are turned on / off. A DC / DC converter having a switch control circuit for boosting the output voltage of a battery, an ignition coil, and an ignition provided on the primary side of the ignition coil and charged to one polarity with the output voltage of the DC / DC converter. Capacitor, a discharge switch provided to conduct electricity when an ignition signal is given and discharge the electric charge accumulated in the ignition capacitor through the primary coil of the ignition coil, and the discharge switch is ignited. Ignition timing control unit for controlling timing of applying signal and converter for controlling boosting operation of the DC / DC converter An ignition device for the DC / DC converter internal combustion engine with a controller having a control unit of interest.

In the present invention, the converter control section is provided with a rotation time measuring means for measuring the time Tn required for the internal combustion engine to make one revolution, and an ignition capacitor from the time Tn measured by the rotation time measuring means. A step-up operation stop time calculating means for calculating the step-up operation stop time T2 (= Tn-T1) by subtracting the time T1 required for charging to a predetermined target voltage, and an ignition timing control unit for an ignition signal to a discharge switch. Is started while the boosting operation stop time T2 is started, and D is measured while the boosting operation stop time is being measured.
A converter start / stop control means for stopping the boosting operation of the C / DC converter and starting the boosting operation of the DC / DC converter when the measurement of the boosting operation stop time is completed is provided.

With the above arrangement, since the ignition signal is given to the discharging switch and the ignition operation is performed at the same time when the charging of the ignition capacitor is completed, the ignition capacitor is maintained in the state where the charging is completed. The time spent can be substantially eliminated. Therefore, it is possible to eliminate the time in which the high voltage across the ignition capacitor is wastefully applied to the components of the ignition device, reduce the burden on the components of the ignition device, and extend the life thereof.

The converter control section also includes control condition detecting means for detecting a control condition used to determine the target value of the terminal voltage when the charging of the ignition capacitor is completed, and the control condition detected by the control condition detecting means. The charging target voltage determining means for determining the target value of the terminal voltage at the time of completion of charging of the ignition capacitor as a target voltage in accordance with
Rotation time measuring means for measuring the time Tn required for rotation and time T1 required for charging the ignition capacitor to the target voltage determined by the charge target voltage determining means with the output of the DC / DC converter is the charging time. And the time Tn measured by the rotation time measuring means.
And a boosting operation stop time calculating means for calculating the boosting operation stop time T2 by subtracting the charging time T1 from the charging time T1 and starting measurement of the boosting operation stop time when the ignition timing control section gives an ignition signal to the discharge switch, And a converter start / stop control means for stopping the boosting operation of the DC converter while measuring the boosting operation stop time and starting the boosting operation of the DC converter when the measurement of the boosting operation stop time is completed. Can also be

The above-mentioned control conditions are the operating condition (starting condition, acceleration condition) of the engine and the surrounding environmental condition (ambient temperature etc.).

The charging target voltage determining means is, for example, a capacitor for ignition in order to improve the ignition performance when the control condition detecting means detects that the operating state of the engine is in the starting state when the ambient temperature is low. Set the target value of the terminal voltage at the time of charging completion higher than that at the time of steady operation, and when the completion of engine start is detected, the target value of the terminal voltage at the time of completion of charging of the ignition capacitor is steady Decrease to the hour value.

The charging voltage determining means also improves the ignition performance when it is detected that the engine is being accelerated, so as to improve the acceleration performance. Set the target value to a value higher than that at constant speed operation, and when the engine returns to the steady state where it operates at constant speed, return the target value of the terminal voltage at the completion of charging the ignition capacitor to the value at steady state. .

In the case of the above configuration, the ignition operation can be performed immediately after charging the ignition capacitor to an optimum voltage value according to the operating state of the engine and the state of the surrounding environment. The start-up performance and acceleration performance of the ignition capacitor are improved, and the time when the high voltage across the ignition capacitor is unnecessarily applied to the components of the ignition device is eliminated to reduce the burden on the components of the ignition device and reduce its life. Can be extended.

The converter control section also includes a rotation time measuring means for measuring the time Tn required for the internal combustion engine to make one revolution, a battery voltage detecting circuit for detecting the terminal voltage of the battery, and a battery voltage detecting circuit for detecting the same. The time T1 required to charge the ignition capacitor to a predetermined target voltage with the voltage obtained by boosting the terminal voltage of the battery thus obtained by the DC / DC converter is calculated as the charging time, and by the rotation time measuring means. The charging time T1 is subtracted from the measured time Tn to obtain the boost operation stop time T2.
The boosting operation stop time calculating means for calculating (= Tn-T1) and the boosting operation stop time T2 are started when the ignition timing control section gives an ignition signal to the discharge switch, and the boosting operation stop time is calculated. And a converter start / stop control means for stopping the step-up operation of the DC / DC converter while the measurement is being performed, and starting the step-up operation of the DC / DC converter when the step-up operation stop time measurement is completed. You can also do it.

In the case of such a configuration, in addition to the advantage that the service life of the components of the ignition device can be extended, the charging voltage of the ignition capacitor becomes insufficient when the voltage of the battery drops. The advantage is that it can be prevented.

The converter control unit also sets the terminal voltage at the time of completion of charging of the ignition capacitor to an optimum value according to various control conditions to enhance the operating performance of the engine and to reduce the ignition performance due to the shortage of the battery voltage. In order to prevent and extend the life of the components of the ignition device, the control condition detecting means for detecting the control condition used for determining the terminal voltage at the time of completion of charging of the ignition capacitor, and the control condition detecting means detect the control condition. Charging target voltage determining means for determining the target value of the terminal voltage at the time of completion of charging of the ignition capacitor as a target voltage according to the control conditions, a battery voltage detection circuit for detecting the terminal voltage of the battery, and the internal combustion engine makes one revolution. DC / D is used to measure the terminal time of the battery detected by the rotation time measuring means for measuring the time Tn required for
The time T1 required to charge the ignition capacitor to the target voltage determined by the charge target voltage determining means with the voltage boosted by the C converter is calculated as the charge time, and the time measured by the rotation time measuring means is calculated. T
A step-up operation stop time calculating means for calculating the step-up operation stop time T2 by subtracting the charging time T1 from n, and measurement of the step-up operation stop time when the ignition timing control unit gives an ignition signal to the discharge switch. A converter start / stop control means for stopping the boosting operation of the DC converter while measuring the boosting operation stop time and starting the boosting operation of the DC converter when the measurement of the boosting operation stop time is completed. It can also be configured.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of the present invention. The ignition device shown in FIG. 1 is provided with a battery 1 whose negative electrode is grounded, a DC / DC converter 2 for boosting the output voltage of the battery 1, an ignition coil 3, and a DC / DC provided on the primary side of the ignition coil. Ignition capacitor 4 charged to one polarity by the output voltage of the converter 2
And a discharge switch 5 provided so as to discharge the electric charge accumulated in the ignition capacitor 4 through the primary coil of the ignition coil 3 when the ignition signal is applied.
And a controller 6 that constitutes an ignition timing control unit that controls the timing of giving an ignition signal to the discharge switch 5 and a converter control unit that controls the step-up operation of the DC / DC converter 2, and gives the rotation speed information of the engine to the controller 6. A pulser 7 for generating a pulse for generating a pulse at a fixed crank angle position of the engine, and a waveform shaping circuit 8 for converting an output pulse of the pulser 7 into a signal having a waveform suitable for input to the controller 6.

More specifically, the DC / DC converter 2 includes a step-up transformer 11, a chopper switch 12 connected in series to the primary coil 11a of the step-up transformer, and a secondary coil 11b of the transformer 11. A diode 13 whose anode is connected to the ground side between one end and the ground, a diode 14 whose anode is connected to the other end of the secondary coil 11b of the step-up transformer, and switch control for controlling ON / OFF of the chopper switch 12. It is composed of a circuit 15. The output voltage of the battery 1 is applied through the key switch 16 to both ends of the series circuit of the primary coil 11 a of the step-up transformer 11 of the DC / DC converter 2 and the chopper switch 12.

In the illustrated example, the MOS whose source is grounded
The FET F1 constitutes a chopper switch 12, and the drain of this FET is connected to one end of the primary coil of the booster coil 11.

The ignition coil 3 has a primary coil 3a and a secondary coil 3b, one end of which is grounded,
The ignition capacitor 4 is connected between the other end of the primary coil 3a and the cathode of the diode 14 of the DC / DC converter 2. The discharging switch 5 is composed of a thyristor Th1, and the thyristor is connected between the connection point of the ignition capacitor 4 and the diode 14 and the ground, with its cathode facing the ground side.

A diode 20 is connected in antiparallel between the anode and cathode of the thyristor Th1 and is connected to the thyristor Th1.
A noise absorbing resistor 21 and a capacitor 22 are connected in parallel between the first gate and the cathode. Ignition coil 3
The non-grounding side terminal of the secondary coil 3b is connected to the non-grounding side terminal of the spark plug 23 attached to the cylinder of the internal combustion engine (not shown) through a high voltage cord.

In this example, the ignition coil 3, the ignition capacitor 4, and the discharge switch 5 (thyristor Th1) are used.
The diode 20, the resistor 21, and the capacitor 22 constitute a known capacitor discharge ignition circuit.

The pulsar 7 is a known signal generator that generates a pulse signal for obtaining crank angle information of the engine, and includes a reluctor 7a1 having a predetermined polar arc angle and is attached to the crankshaft of the engine. -Shaped rotor 7a and a first pulse Vp having different polarities by detecting the front edge and the rear edge of the reluctor 7a1 in the rotational direction.
It is composed of a signal emitting electron 7b for generating the first and second pulses Vp2.

The illustrated pulsar 7 generates the first pulse Vp1 when the crank angle position of the engine coincides with the reference position which is set at a position sufficiently advanced from the position corresponding to the top dead center of the piston. Then, the second pulse Vp2 is generated at the crank angle position corresponding to the ignition timing when the engine is started, which is set near the crank angle position when the piston reaches the top dead center.

The illustrated controller 6 includes a CPU, RO
Microcomputer 2 equipped with M, RAM, timer, etc.
5, and when the microcomputer 25 detects the ignition timing and generates an ignition command signal, the thyristor T of the ignition circuit
An ignition signal output circuit 26 for applying an ignition signal Vi to the gate of h1 is provided. The microcomputer 25 receives the first and second signals S1 and S2 obtained by shaping the first pulse Vp1 and the second pulse Vp2 generated by the pulsar 7 by the waveform shaping circuit 8, respectively. Ports A1 and A2 and converter control signal S
It has a port B1 for outputting o and a port B2 for outputting an ignition command signal Si. Microcomputer 2
The port B1 of No. 5 is the control signal input terminal 15a of the switch control circuit 15, and the port B2 is the ignition signal output circuit 26.
Are connected to the input terminals of.

The switch control circuit 15 operates by using a DC voltage obtained by converting a voltage supplied from the battery 1 through the switch 16 into a constant voltage of an appropriate level by a power supply circuit (not shown) as a power supply voltage. , The converter is oscillated by repeating the operation of turning on the chopper switch 12 for a certain time each time the secondary current of the step-up transformer 11 becomes zero or less than the threshold value, and the secondary coil of the step-up transformer is oscillated. It is a circuit that induces a boosted voltage.

The switch control circuit 15 is, for example, a voltage induced in the secondary coil 11b of the step-up transformer 11 when the chopper switch 12 is switched from the ON state to the OFF state. The secondary current flowing to the side is detected at both ends of the diode 13,
A drive command generation circuit that generates a chopper drive command when the secondary current is detected to be zero, or when it is detected to be lower than a predetermined threshold level, and the drive command is generated. The step-up transformer 11 is composed of a pulse generation circuit which sometimes applies a drive pulse having a predetermined time width to the gate of the chopper switch 12 and turns on the chopper switch 12 only while the drive pulse is generated. Each time the secondary current of (1) becomes zero or less than the threshold value, the chopper switch 12 is turned on for a certain period of time, and then the operation of turning it off is repeated, whereby the pulse boosted to the secondary coil of the step-up transformer 11 is repeated. Induced voltage.

As shown in the figure, DC / DC which obtains a boosted voltage by connecting and disconnecting the primary current of the boosting transformer.
When charging the ignition capacitor with the output of the converter, the chopper switch 12 is operated while the secondary current of the step-up transformer (charging current of the ignition capacitor) is flowing and the magnetic flux is flowing through the iron core of the step-up transformer 11. When the switch is turned on, a large primary current flows through the step-up transformer 11, and it is inevitable that the loss in the primary side circuit of the step-up transformer becomes large. On the other hand, the secondary current of the step-up transformer 11 is detected, and each time the secondary current stops flowing, the chopper switch is driven and kept in the ON state for a certain period of time to perform the chopper operation, thereby making the ignition capacitor. When the battery is charged, the secondary current is flowing in the step-up transformer (the magnetic flux is flowing in the iron core of the step-up transformer)
As a result, it is possible to prevent the state where the current starts to flow in the primary coil of the step-up transformer from occurring, so that it is possible to prevent the loss in the primary side circuit of the step-up transformer from increasing.

The switch control circuit 15 as described above is publicly known, for example, as disclosed in Japanese Patent No. 3119097.

Note that the present invention uses the switch control circuit 15 configured to detect the secondary current of the boost coil as described above and flow the primary current to the boost coil when the secondary current is not flowing. The present invention is not limited to the case, and the switch control circuit 15 may be configured to include an oscillator that oscillates at a constant frequency, and to provide the chopper switch 12 with a drive signal that is intermittent at a constant frequency from the oscillator. .

In the present embodiment, when the control signal input terminal 15a of the switch control circuit 15 receives the control signal So having the logical value "1" (at the H level), the drive signal to the chopper switch 12 is generated. The switch control circuit 15 is provided with a chopper switch drive stopping means for stopping the supply of the chopper.

In the ignition device for an internal combustion engine shown in FIG. 1, when the key switch 16 is closed, the DC / DC converter 2 starts a boosting operation (oscillation), and the converter 2
Every time the chopper switch 12 is switched from the ON state to the OFF state, the high voltage boosted in the secondary coil 11b of the step-up transformer 11 is induced. With the output voltage of this converter,
Secondary coil 11b of step-up transformer-diode 14-ignition capacitor 4-primary coil of ignition coil 3-diode 13-secondary coil 11b of step-up transformer, a charging current of the ignition capacitor 4 flows, and the ignition capacitor Is charged to the polarity shown. DC / DC converter 2
Since the voltage induced in the secondary coil of the step-up transformer is a pulse voltage, the ignition capacitor 4 is gradually charged. The controller 6 gives the ignition command signal Si to the ignition signal output circuit 26 by keeping the potential of the port B2 of the microcomputer 25 at the H level for a certain time at the ignition timing of the internal combustion engine. When the ignition command signal Si is given, the ignition signal output circuit 26 gives the ignition signal Vi having a constant pulse width to the gate of the thyristor Th1 which constitutes the discharge switch. As a result, the thyristor Th1 becomes conductive, so that the charge of the ignition capacitor 4 is changed to the thyristor T1.
discharge through h1 and the primary coil 3a of the ignition coil,
A high voltage is induced in the primary coil 3a of the ignition coil.
Since this voltage is boosted by the primary and secondary winding ratio of the ignition coil, a high voltage for ignition is induced in the secondary coil 3b of the ignition coil. Since this high voltage is applied to the spark plug 23, spark discharge is generated in the spark plug 23 and the engine is ignited.

In the internal combustion engine ignition device shown in FIG. 1, the microcomputer 25 executes a predetermined program to calculate the engine speed from the pulse generation interval output from the pulser 7. Or an ignition timing calculation means for calculating the ignition timing of the internal combustion engine with respect to the calculated rotation speed, or a measurement value for measuring the ignition timing calculated when the pulsar 7 generates the first pulse Vp1. Is set to the ignition timer and the measurement is started, and then various function realizing means such as an ignition timing detecting means for outputting the ignition command signal Si from the port B2 when the measurement of the ignition timing is completed is configured. By the microcomputer 25, the program used to configure the above function realizing means, and the ignition signal output circuit 26,
An ignition timing control unit is configured.

By causing the microcomputer to execute a predetermined program, the step-up operation of the DC / DC converter 2 is stopped for a predetermined step-up operation stop time, and the step-up of the DC / DC converter 2 is performed during a period other than the step-up stop time. A converter control means for controlling the switch control circuit 15 is implemented so that the operation is performed. A program for configuring this converter control means and the microcomputer 25 constitute a converter control unit.

A conventional ignition device of this type is provided with a voltage detection circuit for detecting the charging voltage of the ignition capacitor 4, and the terminal voltage of the ignition capacitor detected by the voltage detection circuit is set to a set value. When it reached, the boosting operation of the converter 2 was stopped so that the maximum value of the terminal voltage of the ignition capacitor was maintained at the set value. However, in the present invention, the ignition capacitor 4 is kept up to the target voltage. The step-up operation of the DC / DC converter is performed only for the time required for charging. Since the present invention does not particularly require a circuit for detecting the terminal voltage of the ignition capacitor, the circuit for detecting the terminal voltage of the ignition capacitor 4 is omitted in the example shown in FIG. However, in the present invention, a circuit for detecting the terminal voltage of the ignition capacitor (for example, detecting the voltage across the thyristor Th1) is provided, and when the terminal voltage of the ignition capacitor exceeds the limit value, DC / DC is set. It does not hinder the combined use of the control for stopping the boosting operation of the converter 2.

The hardware configuration of the ignition device shown in FIG. 1 is the same as that of the conventional ignition device of this type except for the above points.

In the conventional ignition device, when the microcomputer 25 sets the potential of the port B2 to the H level at the ignition timing to perform the ignition operation, the potential of the port B1 is short enough to turn off the thyristor Th1. Only during the time To, the H level is set to stop the boosting operation of the DC / DC converter 2.

On the other hand, in the present invention, the time T1 required to charge the ignition capacitor 4 to the predetermined target voltage is obtained as the charging time, and the crankshaft of the engine is set to 1
The boosting operation stop time T2 is calculated by subtracting the charging time T1 from the time Tn required for rotation, and the ignition command signal Si is output from the port B2 of the controller 6 at the engine ignition timing, and at the same time, the calculated boosting operation is performed. The converter control signal So that maintains the H level during the stop time T2 is applied to the switch control circuit 15 to stop the step-up operation of the DC / DC converter during the step-up operation stop time.

In the conventional ignition device of this kind, the waveform of the pulse generated by the pulsar 7, the waveform of the terminal voltage Vc of the ignition capacitor 4, and the waveform of the converter control signal So output from the port B1 of the microcomputer 25. And the waveform of the ignition command signal Si output from the port B2 are shown in FIGS.

As is apparent from FIG. 2, in the conventional ignition device, at the ignition timing ti, the ignition command signal Si is generated, and at the same time, the converter control signal So is supplied only for a short time Ta required to turn off the thyristor. H
As the level, the boosting operation of the converter is stopped, and the boosting operation of the converter 2 is immediately restarted when the time Ta elapses to charge the ignition capacitor 4.
Therefore, the ignition capacitor 4 is used for most of the time (Tn-Ta) in the time Tn required for the engine to make one revolution.
Is maintained in a charging completed state, and the high voltage (200 volts to 200 tens of volts) across the ignition capacitor 4 is continuously applied to the ignition thyristor Th1 and the diode 20. Therefore, the time during which a high voltage is wastefully applied to the thyristor Th1 and the diode 20 becomes long,
There has been a problem that the service life of these circuit components is shortened.

Therefore, in the present invention, the converter control unit formed by the controller 6 is provided with the internal combustion engine 1
Rotation time measuring means for measuring the time Tn required for rotation, and time Tn required for charging the ignition capacitor to a predetermined target voltage from the time Tn measured by the rotation time measuring means Operation stop time T2
The boosting operation stop time calculating means for calculating (= Tn-T1) and the boosting operation stop time T2 are started when the ignition timing control section gives an ignition signal to the discharge switch, and the boosting operation stop time is calculated. There is provided converter start / stop control means for stopping the step-up operation of the DC / DC converter while the measurement is being performed, and starting the step-up operation of the DC / DC converter when the measurement of the step-up operation stop time is completed.

A time chart for explaining the operation of the ignition device according to the present invention is shown in FIG. FIG. 3A is a graph showing the time counting operation of the timer in the microcomputer 25, and FIGS. 3B to 3E are pulse waveforms output from the pulser 7 and the charging voltage Vc of the ignition capacitor 4, respectively.
3 is a waveform diagram schematically showing the waveform of No. 1, the waveform of a converter control signal So for controlling the DC / DC converter 2, and the waveform of an ignition command signal Si.

In this embodiment, the ignition capacitor 4 is charged to a constant target voltage Vc1. The target voltage Vc1 is preset to a necessary and sufficient value for accumulating the energy necessary for obtaining a predetermined ignition performance in the ignition capacitor 4. Microcomputer 25
When the pulsar 7 generates the first pulse Vp1,
After reading the measured value of the timer, the timer is reset to start the time counting operation of counting clock pulses.
The microcomputer 25 calculates the rotational speed of the engine from the measured value Tn of the timer (time required for the crankshaft of the engine to make one revolution) read every time the first pulse Vp1 is generated.

The microcomputer 25 also subtracts the time T1 required to charge the ignition capacitor 4 to the target voltage Vc1 from the time Tn required for the engine to make one revolution, whereby the boosting operation stop time T2 (= Tn-T1). ) Is calculated, and when the ignition command signal Si is generated by setting the potential of the port B2 to the H level at the ignition timing ti of the engine, the boosting operation stop time T2 is set to a timer different from the above timer and the measurement is performed. Let it start. Then, after the ignition command signal is generated at the ignition timing, when the measurement of the boosting operation stop time T2 is completed, the potential of the port B1 (converter control signal) is set to the L level (low level), and the DC / DC converter 2 After the boosting operation of No. 1 is restarted and the ignition capacitor 4 is charged for the set time T1, the potential of the port B1 is set to the H level at the ignition timing ti to perform the ignition operation.

As described above, in the present invention, after the ignition operation is performed, until the timing when the time T1 required for charging the ignition capacitor remains until the next ignition timing, the DC is maintained. Since the start of the charging of the ignition capacitor 4 is delayed by stopping the step-up operation of the / DC converter, the ignition capacitor 4 is charged for the required charging time T1 and immediately after the next ignition timing. ti
Ignition operation is performed. Therefore, the ignition capacitor 4
Is not held in a fully charged state for a long time, it is possible to shorten the time for which a high voltage is applied to the circuit components such as the discharge switch 5 and the diode 20, and to extend the life of these components. Can be achieved.

In the above control, if each ignition timing is advanced or retarded with respect to the ignition timing one revolution before, the charging capacitor charging time T1 is set to the set target value. However, if the charging time T1 (target voltage Vc1) is set with a margin, there will be no practical problem.

4 and 5 are flowcharts showing the algorithm of the program executed by the microcomputer 25 in the present embodiment. FIG. 4 (A) shows
The algorithm of the main routine is shown, and FIG. 7B shows the first pulse interrupt routine executed when the pulser 7 generates the first pulse Vp1. Also in FIG.
FIG. 5A shows an ignition timer interrupt routine executed when the ignition timer provided in the microcomputer completes the measurement of the ignition timing (when the calculated ignition timing is detected), and FIG. It is a T2 timer interrupt routine that is executed when the timer for measuring the boosting operation stop time T2 measures the stop time T2.

In the case of the algorithms shown in these figures, step 1 of the main routine is first executed when the power supply of the microcomputer is established, and each unit is initialized. Then step 2 of the main routine
In step 3, the rotation speed is calculated, and in step 3, the ignition timing at the calculated rotation speed is calculated. After that, after performing other necessary processing in step 4, the process returns to step 2. The calculation of the rotation speed in step 2 is performed by the time T measured in the interrupt routine of FIG.
n (the time required for the engine to make one revolution).

In the interrupt routine of FIG. 4B which is executed each time the pulser generates the first pulse Vp1, the time to be measured by the ignition timer in order to measure the ignition timing calculated in step 3 of the main routine is set. The ignition timer is set and the measurement is started. Next, in step 2, the measured value (time required for the engine to make one revolution) of the timer that performs the timing operation as shown in FIG. 3A is read as Tn, and in step 3, it is stored as a constant in ROM from Tn. The boosting operation stop time T2 is calculated by performing the calculation for reducing the charging time T1. Next, if there is further necessary processing, that processing is performed in step 4 and the process returns to the main routine.

When the measurement of the time when the ignition timer is set is completed, the ignition timer interrupt routine shown in FIG. 5A is executed. In this interrupt routine, in step 1, the potential of the port B2 is set to the H level (the logical value is "1") to generate the ignition command signal Si, and the ignition signal output circuit 26 outputs the ignition signal Vi to the gate of the thyristor Th1. give. As a result, the thyristor Th1 is turned on and the ignition operation is performed. Next, in step 2, the step-up operation stop time T2 that has already been calculated is set in the timer for measuring the step-up operation stop time, the measurement is started, and the potential of the port B1 is set to H in step 3.
The level is set to stop the boosting operation of the DC / DC converter 2. If there is a further necessary process, the process is performed in step 4, and then the process returns to the main routine.

When the timer for measuring the boosting operation stop time T2 completes the measurement, the interrupt routine of FIG. 5B is executed. In this interrupt routine, step 1
, The potential of port B1 is at L level (logical value is "0")
Then, the boosting operation of the DC / DC converter 2 is restarted. If there is more processing required, step 2
After that, the process is executed and the process returns to the main routine.

In this embodiment, the rotation speed calculation means is realized by step 2 of the main routine of FIG.
The ignition timing calculation means is constituted by step 3. Further, step 2 of FIG. 4 (B) constitutes rotation time measuring means for measuring the time Tn required for the internal combustion engine to make one revolution, and step 3 constitutes boosting operation stop time calculating means. Further, the converter start / stop control means is constituted by steps 2 and 3 of the interrupt routine of FIG. 5 (A) and the interrupt routine of FIG. 5 (B).

Further, the ignition timing detecting means is constituted by the step 1 of FIG. 4 (B) and the ignition timer.
The ignition command signal output means is constituted by step 1 of the interrupt routine of FIG.

FIG. 6 shows the configuration of the second embodiment of the present invention. When starting or accelerating the engine, it is desirable to increase the terminal voltage at the time of completion of charging of the ignition capacitor in order to improve the ignition performance. Similarly, when starting the engine in a state where the ambient temperature is low, it is desirable to increase the terminal voltage when the ignition capacitor is completely charged.
Therefore, when importance is attached to the running performance of a vehicle driven by an internal combustion engine, or when it is expected to be used in cold regions, the control condition that determines the charging voltage of the ignition capacitor is detected and detected. It is preferable to determine the target value of the terminal voltage when the charging of the ignition capacitor is completed according to the result. Therefore, in the example shown in FIG. 6, the control condition detecting means 27 for detecting the control condition used for determining the target value of the terminal voltage when the charging of the ignition capacitor 4 is completed is provided, and this detection is performed. The control condition detected by the means is input to the port A3 of the microcomputer 25.

The above-mentioned control conditions are the operating condition of the engine (whether the engine is in a starting condition or an acceleration condition) and the ambient environmental conditions (ambient temperature etc.).

In FIG. 6, the control condition detecting means 2
7 is provided outside the microcomputer 25, which is used when a temperature sensor that detects the ambient temperature of the engine is used as a means for detecting the control condition, or when the opening of the throttle valve of the engine changes. This is because it is assumed that a throttle sensor that detects the opening of the throttle valve is used to detect that a sudden acceleration operation has been performed. When detecting the control condition from the data processed inside the microcomputer, as in the case of detecting the acceleration state from the change of the rotation speed of the engine, the control condition detecting means is configured on software.

In this embodiment, the converter control unit provided in the controller 6 is replaced by the control condition detecting means 27.
Charging target voltage determining means for determining a target value of the terminal voltage at the time of completion of charging the ignition capacitor 4 as a target voltage according to the control condition detected by the control condition detecting means,
It is necessary to charge the rotation time measuring means for measuring the time Tn required for the internal combustion engine to make one revolution and the ignition capacitor to the target voltage determined by the charge target voltage determining means with the output of the DC / DC converter 2. Charging time calculating means for calculating the time T1 as the charging time, boosting operation stop time calculating means for calculating the boosting operation stop time T2 by subtracting the charging time T1 from the time Tn measured by the rotation time measuring means, and ignition timing control. Section starts measuring the boosting operation stop time when the ignition signal is supplied to the discharge switch, and stops the boosting operation of the DC converter while the boosting operation stop time is being measured. A converter start / stop control means for starting the boosting operation of the DC converter when the measurement is completed is provided.

The charging target voltage determining means is for ignition in order to improve the ignition performance, for example, when the control condition detecting means 27 detects that the operating state of the engine is the starting state in a state where the ambient temperature is low. The target value of the terminal voltage at the time of completion of charging the capacitor 4 is set higher than the value at the time of steady operation, and when it is detected that the start of the engine is completed, the charging voltage of the ignition capacitor is set to the value at the time of steady operation. Lower.

The charging target voltage determination means also improves the ignition performance when it is detected that the engine is being accelerated, and enhances the acceleration performance. Set the target voltage value to a value higher than that at constant speed operation, and set the steady-state value to the terminal voltage target value when the ignition capacitor is fully charged when the engine returns to the constant speed operation state. return.

In the illustrated ignition device, if the electrostatic capacitance of the ignition capacitor is sufficiently large, the terminal voltage Vc of the ignition capacitor 4 linearly increases with the passage of time and reaches the target value. FIG. 8 shows an example of the relationship between the terminal voltage Vc of the ignition capacitor 4 and the charging time T. In this example, between the terminal voltage Vc and the charging time T,
There is a relationship of T = (3/100) * Vc (* is a multiplication symbol).

As described above, since the relationship between the terminal voltage of the ignition capacitor and the charging time T of the ignition capacitor can be expressed by a mathematical expression, when the target value of the terminal voltage of the ignition capacitor is determined, the target value is reached. The charging time T1 required to charge the ignition capacitor can be easily calculated.

FIGS. 7A to 7D show the waveform of the pulse output by the pulser 7, the waveform of the charging voltage Vc of the ignition capacitor, and the converter control signal S in this embodiment.
The waveform of o and the waveform of the ignition command signal Si are shown. As shown in these figures, in this embodiment, the target value of the charging voltage of the ignition capacitor 4 is set to a high value V.
When setting to c1, the charging time is lengthened as T11 and the boosting operation stop time is shortened as T21, and the target value of the terminal voltage at the time of completion of charging of the ignition capacitor is set to the low value Vc.
When it is set to 2, the charging time is shortened as T12 and the boosting operation stop time is lengthened as T22. By changing the charging time between T11 and T12 and changing the boosting operation stop time between T21 and T22 according to the charging time, the terminal voltage at the time of completion of charging of the ignition capacitor is set to Vc1 and Vc2. Can vary between

9 and 10 are flowcharts showing the algorithm of the program executed by the microcomputer 25 in the present embodiment. 9A shows a main routine, and FIG. 9B shows a first pulse interrupt routine. 10 (A) and (B)
Shows an ignition timer interrupt routine and a T2 timer interrupt routine, respectively.

In the case of this algorithm, the control condition detecting means 27 is used in step 4 of the main routine.
The operating state of the engine is detected as a control condition from the output of the above, and in step 5, the value of the charging voltage Vc at the time of completion of charging is determined according to the detected operating state. Other configurations of the main routine are the same as those shown in FIG.

Further, in this example, since the charging characteristic of the ignition capacitor is as shown in FIG. 8, in the step 3 of the interrupt routine of FIG. 9B, the above-mentioned arithmetic expression T2 = Tn.
-(3/100) * Vc is used for boost operation stop time T2
Is being calculated. Other configurations of the first pulse interrupt routine are similar to those of the example shown in FIG.
The configurations of the ignition timer interrupt routine and the T2 timer interrupt routine shown in (A) and (B) are the same as those shown in FIGS. 5 (A) and 5 (B).

FIG. 11 shows the third embodiment of the present invention. In this example, a voltage detection circuit 30 for detecting the terminal voltage Vb of the battery 1 through the key switch 16 is provided. The illustrated voltage detection circuit 30 is composed of a resistance voltage dividing circuit including a series circuit of resistors R1 and R2.
The output signal is input to the analog input port A4 of the microcomputer 25. The other points are the same as those of the example shown in FIG. A time chart showing the operation of this embodiment is shown in FIG.

In the ignition device which charges the ignition capacitor with the voltage obtained by boosting the output voltage of the battery by the DC / DC converter, the charging time constant of the ignition capacitor 4 changes with the battery voltage. When the voltage Vb across the battery 1 is high (for example, 15 V),
Since the charging time constant of the ignition capacitor 4 is small, the terminal voltage of the ignition capacitor 4 is the curve a in FIG.
Ascends with a large slope. On the other hand, when the voltage across the battery is low (for example, 8 V), the charging time constant of the ignition capacitor 4 is large, and therefore the terminal voltage of the ignition capacitor is equal to the curve b in FIG. ，
Like b ', it rises with a small inclination. Now, assuming that the time required to charge the ignition capacitor to the target voltage Vcs is T11 when the terminal voltage of the battery is sufficiently high (for example, 15V), when the battery voltage is low (for example, 8V). The same charging time T11
12B, the terminal voltage at the completion of charging of the ignition capacitor is Vc as shown by the curve b ′ in FIG.
s'(<Vcs), and the charging voltage of the ignition capacitor becomes insufficient. Therefore, in the present embodiment, the charging time T1 of the ignition capacitor is determined according to the detected value of the terminal voltage of the battery, and when the terminal voltage of the battery is 8 [V], the charging time is set to T12 (> T11). , So that the ignition capacitor can be charged up to the set charging voltage Vcs.

When the charging time is T11 because the terminal voltage of the battery is high, the boosting operation stop time becomes T21 as shown in FIG. 12C, and the charging time is reduced because the terminal voltage of the battery is low. When set to T12,
The boosting operation stop time becomes T22.

Although not shown in FIG. 12, also in this embodiment, the target value of the terminal voltage at the time of completion of charging the ignition capacitor is determined according to the control condition detected by the control condition detecting means 27. I am trying.

Similar to the example shown in FIG. 8, assuming that there is a linear function between the terminal voltage of the ignition capacitor and the charging time, the coefficient determined by the battery voltage (the slope of the rise of the terminal voltage of the ignition capacitor) ) Is k and the target value of the terminal voltage at the completion of charging of the ignition capacitor is Vcs, the time T1 required to charge the ignition capacitor to the target value Vcs is T1 = (k / 100) * Vcs It can be obtained, and the boost operation stop time T2 is T2 = Tn−
It can be calculated by (k / 100) * Vcs.

13 and 14 are flowcharts showing the algorithm of the program executed by the microcomputer 25 in this embodiment. In this example,
In step 6 of the main routine shown in FIG. 13A, the terminal voltage Vb of the battery is read, and in step 7, the coefficient k is calculated for the detected battery voltage Vb. The calculation of the coefficient k can be performed by using a map or a calculation formula (which is experimentally determined in advance) that gives a relationship between the battery voltage Vb and the coefficient k. The other configuration of the main routine is the same as the example shown in FIG.

In step 3 of the first pulse interrupt routine of FIG. 13B, the boosting operation stop time T2 is calculated using the coefficient k and the calculation formula T2 = Tn- (k / 100) * Vcs. ing. Other configurations of the first pulse interrupt routine are similar to those of the example shown in FIG. 4B, and the ignition timer interrupt routine of FIG. 14A and the T2 timer interrupt routine of FIG.
The ignition timer interrupt routine and the T2 timer interrupt routine shown in FIGS. 5A and 5B are configured in the same manner.

When the terminal voltage of the battery is detected as described above and the charging time of the ignition capacitor is controlled according to the detected voltage, the charging voltage of the ignition capacitor is charged when the battery is exhausted. It is possible to prevent the ignition performance from deteriorating due to lack of fuel.

In the embodiment shown in FIGS. 11 to 14, the target value of the terminal voltage at the time of completion of charging of the ignition capacitor is controlled according to the control condition, and the ignition capacitor is controlled with respect to the terminal voltage of the battery. Although the charging time is controlled, the control of the target value of the battery terminal voltage for the control condition may be omitted. In that case, the control condition detecting means 27 is omitted, and the charging time T1 of the ignition capacitor is stored in the ROM as a constant.

[0077]

As described above, according to the present invention, the time T1 required for charging the ignition capacitor to the predetermined target voltage is the time T required for the engine to rotate once.
By subtracting from n, the boost operation stop time T2 (= T
n-T1) is calculated, and the boosting operation stop time T is calculated from the ignition timing.
Since the boosting operation of the DC / DC converter is stopped during the period of 2, the discharging switch can be made to perform the ignition operation at the same time when the charging of the ignition capacitor is completed. Therefore, the time when the high voltage across the ignition capacitor is unnecessarily applied to the components of the ignition device is eliminated,
There is an advantage that the burden on the components of the ignition device can be reduced and the life of the ignition device can be extended.

Further, in the present invention, means for detecting a control condition for determining the target value of the terminal voltage when the charging of the ignition capacitor is completed is provided, and the terminal when the charging of the ignition capacitor is completed according to the detected control condition. When the target value of the voltage is determined, the ignition operation can be performed immediately after charging the ignition capacitor to the optimum voltage value according to the operating state of the engine and the state of the surrounding environment. While improving the starting performance and acceleration performance of the engine, by eliminating the time when the high voltage across the ignition capacitor is unnecessarily applied to the components of the ignition device, the burden on the components of the ignition device is reduced. The life can be extended.

Further, in the present invention, when the terminal voltage of the battery is detected and the charging time of the ignition capacitor is determined according to the detected battery voltage,
Since the ignition capacitor can be charged to the target voltage even when the battery voltage drops, it is possible to prevent the ignition performance from deteriorating due to insufficient charging voltage of the ignition capacitor when the battery is exhausted. .

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a hardware configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a waveform diagram schematically showing a signal of each part of a conventional ignition device having a configuration similar to that of the example shown in FIG. 1 and a waveform of a terminal voltage of an ignition capacitor.

FIG. 3 is a waveform diagram schematically showing a signal waveform of each part and a waveform of a terminal voltage of an ignition capacitor according to the first embodiment of the present invention.

4A and 4B are flowcharts showing algorithms of a main routine and a first pulse interrupt routine of a program executed by the microcomputer of the controller in the first embodiment of the present invention.

5A and 5B are respectively executed when an ignition timer interrupt routine and a boost operation stop time T2 of a program executed by the microcomputer of the controller in the first embodiment of the present invention are measured. T
It is the flowchart which showed the algorithm of the 2 timer interruption routine.

FIG. 6 is a circuit diagram showing a hardware configuration of a second exemplary embodiment of the present invention.

FIG. 7 is a waveform diagram schematically showing a signal waveform of each part and a waveform of a terminal voltage of an ignition capacitor according to a second embodiment of the present invention.

FIG. 8 is a graph showing an example of charging characteristics of an ignition capacitor.

9A and 9B are flowcharts showing algorithms of a main routine and a first pulse interrupt routine of a program executed by the microcomputer of the controller in the second embodiment of the present invention.

10A and 10B are flowcharts showing algorithms of an ignition timer interrupt routine and a T2 timer interrupt routine of a program executed by a microcomputer of a controller in the second embodiment of the present invention.

FIG. 11 is a circuit diagram showing a hardware configuration of a third exemplary embodiment of the present invention.

FIG. 12 is a waveform diagram schematically showing a signal waveform of each part and a waveform of a terminal voltage of an ignition capacitor according to a third embodiment of the present invention.

13A and 13B are flowcharts showing algorithms of a main routine and a first pulse interrupt routine of a program executed by the microcomputer of the controller in the third embodiment of the present invention.

14A and 14B are flow charts showing algorithms of an ignition timer interrupt routine and a T2 timer interrupt routine of a program executed by a microcomputer of a controller in the second embodiment of the present invention.

[Explanation of symbols]

1 ... Battery, 2 ... DC / DC converter, 3 ... Ignition coil, 4 ... Ignition capacitor, 5 ... Discharge switch, 6
... Controller, 7 ... Pulser, 11 ... Step-up transformer, 1
2 ... Chopper switch, 25 ... Microcomputer, 26 ... Ignition signal output circuit, 27 ... Control condition detecting means.

Continued front page    F term (reference) 3G019 AC01 AC04 BA02 DB06 EB06                       FA13 FA26 GA01 GA05 GA07                       GA09 GA13

Claims (4)

[Claims] 1. A step-up transformer to which a primary current is supplied from a battery, a chopper switch provided to turn on / off the primary current of the step-up transformer, and a switch control circuit for turning on / off the chopper switch. A DC / DC converter for boosting the output voltage of the battery, an ignition coil, an ignition capacitor provided on the primary side of the ignition coil and charged to one polarity with the output voltage of the DC / DC converter, and an ignition signal. And a discharge switch provided to discharge the electric charge accumulated in the ignition capacitor through the primary coil of the ignition coil when the electric current is given, and a timing of giving an ignition signal to the discharge switch. And a converter control unit for controlling the boosting operation of the DC / DC converter. In a DC / DC converter type internal combustion engine ignition device including a controller, the converter control unit measures a time Tn required for the internal combustion engine to make one rotation, and a rotation time measuring unit. The boosting operation stop time T2 is obtained by subtracting the time T1 required to charge the ignition capacitor to a predetermined target voltage from the time Tn measured by
(= Tn-T1) for boosting operation stop time calculation means, and when the ignition timing control section gives an ignition signal to the discharge switch, starts measuring the boosting operation stop time T2 to increase the boosting operation. The DC during the measurement of the operation stop time
/ DC converter for stopping the boosting operation of the DC / DC converter and starting the boosting operation of the DC / DC converter when the measurement of the boosting operation stop time is completed. / DC converter type internal combustion engine ignition device. 2. A step-up transformer supplied with a primary current from a battery, a chopper switch provided to turn on / off the primary current of the step-up transformer, and a switch control circuit for turning on / off the chopper switch. A DC / DC converter for boosting the output voltage of the battery, an ignition coil, an ignition capacitor provided on the primary side of the ignition coil and charged to one polarity with the output voltage of the DC / DC converter, and an ignition signal. And a discharge switch provided to discharge the electric charge accumulated in the ignition capacitor through the primary coil of the ignition coil when the electric current is given, and a timing of giving an ignition signal to the discharge switch. And a converter control unit for controlling the boosting operation of the DC / DC converter. In a DC / DC converter type internal combustion engine ignition device including a controller, the converter control unit detects a control condition for detecting a control condition used to determine a target value of a terminal voltage when the ignition capacitor is completely charged. Means, charging target voltage determining means for determining a target value of a terminal voltage at the time of completion of charging of the ignition capacitor as a target voltage in accordance with the control condition detected by the control condition detecting means, and the internal combustion engine makes one revolution. A rotation time measuring means for measuring a time Tn required for charging, and a time T1 required for charging the ignition capacitor to the target voltage determined by the charging target voltage determining means with the output of the DC / DC converter. The time is calculated as time, and the charging time T1 is subtracted from the time Tn measured by the rotation time measuring means to increase the voltage. A step-up operation stop time calculating means for calculating an operation stop time T2 (= Tn-T1), and measurement of the step-up operation stop time T2 is started when the ignition timing control section gives an ignition signal to the discharge switch. Then, while the step-up operation stop time is being measured, the DC
And a converter start / stop control means for stopping the boosting operation of the converter and starting the boosting operation of the DC converter when the measurement of the boosting operation stop time is completed. Ignition device. 3. A step-up transformer supplied with a primary current from a battery, a chopper switch provided to turn on / off the primary current of the step-up transformer, and a switch control circuit for turning on / off the chopper switch. A DC / DC converter for boosting the output voltage of the battery, an ignition coil, an ignition capacitor provided on the primary side of the ignition coil and charged to one polarity with the output voltage of the DC / DC converter, and an ignition signal. And a discharge switch provided to discharge the electric charge accumulated in the ignition capacitor through the primary coil of the ignition coil when the electric current is given, and a timing of giving an ignition signal to the discharge switch. And a converter control unit for controlling the boosting operation of the DC / DC converter. In a DC / DC converter type internal combustion engine ignition device including a controller, the converter control unit measures rotation time measuring means for measuring a time Tn required for the internal combustion engine to make one rotation, and a terminal voltage of the battery. And a battery voltage detection circuit for detecting the voltage, and a voltage obtained by boosting the voltage detected by the battery voltage detection circuit by the DC / DC converter to charge the ignition capacitor to a predetermined target voltage. The time T1 is calculated as the charging time, and the charging time T1 is subtracted from the time Tn measured by the rotation time measuring means to obtain the boosting operation stop time T2 (=
Tn-T1) boosting operation stop time calculating means, and when the ignition timing control unit gives an ignition signal to the discharge switch, starts measuring the boosting operation stop time T2 to stop the boosting operation. DC while measuring time
/ DC converter for stopping the boosting operation of the DC / DC converter and starting the boosting operation of the DC / DC converter when the measurement of the boosting operation stop time is completed. / DC converter type internal combustion engine ignition device. 4. A step-up transformer supplied with a primary current from a battery, a chopper switch provided so as to turn on / off the primary current of the step-up transformer, and a switch control circuit for turning on / off the chopper switch. A DC / DC converter for boosting the output voltage of the battery, an ignition coil, an ignition capacitor provided on the primary side of the ignition coil and charged to one polarity with the output voltage of the DC / DC converter, and an ignition signal. And a discharge switch provided to discharge the electric charge accumulated in the ignition capacitor through the primary coil of the ignition coil when the electric current is given, and a timing of giving an ignition signal to the discharge switch. And a converter control unit for controlling the boosting operation of the DC / DC converter. In a DC / DC converter type internal combustion engine ignition device including a controller, the converter control unit detects a control condition for detecting a control condition used to determine a target value of a terminal voltage when the ignition capacitor is completely charged. Means, a charging target voltage determining means for determining a target value of a terminal voltage at the time of completion of charging of the ignition capacitor as a target voltage in accordance with the control condition detected by the control condition detecting means, and detecting a terminal voltage of the battery. A battery voltage detection circuit, rotation time measuring means for measuring the time Tn required for the internal combustion engine to make one revolution, and a DC / DC converter for boosting the terminal voltage of the battery detected by the battery voltage detection circuit. The charging capacitor is charged to the target voltage determined by the charging target voltage determining means with the obtained voltage. Thereby calculating the time T1 required for the charging time, the rotation time measurement the charging time T1 of the reduced step-up operation stop time from the time measured Tn by means T2 (= Tn-T1)
A boosting operation stop time calculating means for calculating the boosting operation stop time T2 when the ignition timing control section gives an ignition signal to the discharge switch, and starts measuring the boosting operation stop time T2. DC while going
And a converter start / stop control means for stopping the boosting operation of the converter and starting the boosting operation of the DC converter when the measurement of the boosting operation stop time is completed. Ignition device.