JP6412572B2 - Ignition device for internal combustion engine - Google Patents

Description

  The present invention relates to a current interrupting type ignition device for an internal combustion engine.

  As a current interrupting type ignition device for an internal combustion engine, as shown in Patent Literature 1 and Patent Literature 2, a permanent magnet is attached to the outer periphery of a flywheel attached to the crankshaft of the engine to provide a three-pole magnet field. A magnet generator (flywheel magnet) composed of a magnet rotor configured as shown in FIG. 1 and a stator formed by winding an ignition coil around an iron core having a pair of magnetic pole portions facing the magnetic poles of the magnet rotor is used as an ignition power source. The batteryless ignition device used is widely adopted.

  In the magnet generator used in this type of ignition device, the primary coil of the ignition coil also serves as the power generation coil for the ignition power source, and the first half wave having one polarity and the other polarity having the first polarity. AC voltage having a waveform in which a second half wave having a peak value higher than that of the first half wave and a third half wave having one polarity and the same peak value as the first half wave appear sequentially However, it is induced in the primary coil only once during one rotation of the crankshaft. Of the first to third half-wave voltages induced in the primary coil, the main half-wave with the highest peak value is the second half-wave, and this second half-wave voltage is used to obtain ignition energy. Used.

  Both ends of the primary coil of the ignition coil provided in the stator of the magnet generator are connected in parallel with current control switches composed of semiconductor switch elements such as IGBTs and bipolar transistors that can be controlled on and off. The switch and the magnet generator constitute an ignition circuit. An ignition control unit is provided for controlling the ignition timing of the internal combustion engine by controlling the timing at which the current control switch is switched from the on state to the off state at the engine ignition timing. The ignition control unit and the ignition circuit A current interrupting type ignition device for an internal combustion engine is configured.

  In the ignition device disclosed in Patent Document 1, when the current control switch is composed of an NPN transistor, and the second half-wave voltage is induced in the primary coil of the ignition coil, the collector potential of the transistor is The collector-emitter circuit of the transistor is connected in parallel to both ends of the primary coil of the ignition coil so as to have a positive potential with respect to the emitter. In addition, the collector and base of the transistor are connected through a biasing resistor, and the second half-wave voltage induced in the primary coil of the ignition coil reaches a predetermined level and passes through the biasing resistor from the collector side of the transistor. When a base current of a predetermined magnitude flows through the transistor (when a drive signal for turning on the transistor is given), the transistor is turned on.

  In the ignition device disclosed in Patent Document 1, a thyristor is connected between the base and emitter of the transistor constituting the current control switch, and the thyristor is turned on at the ignition timing of the internal combustion engine. The transistor that has been in the on state until is turned off. When the transistor is turned off, the primary current flowing from the primary coil of the ignition coil through the collector-emitter of the transistor is cut off, so the primary current that has been flowing so far will continue to flow through the primary coil of the ignition coil. A high voltage is induced, and this voltage is boosted to a high voltage for ignition by a boost ratio between the primary and secondary of the ignition coil. Since the high voltage for ignition induced in the secondary coil of the ignition coil is applied to the spark plug attached to the cylinder of the internal combustion engine, a spark discharge is generated in the discharge gap of the spark plug and the engine is ignited.

  As described above, in the current interruption type ignition device, the secondary coil of the ignition coil is ignited by changing the current control switch connected in parallel to the primary coil of the ignition coil from the on state to the off state. The ignition timing of the engine can be controlled by providing an ignition control unit that controls the timing of switching the current control switch from the on state to the off state in order to induce a high voltage for ignition.

  In the ignition device disclosed in Patent Document 1, a microcomputer is provided to configure an ignition control unit, and a trigger is provided on the primary side of the ignition coil in order to supply the microcomputer with power supply voltage and engine rotation information. A coil is provided. The trigger coil is provided so as to induce a voltage having the same phase as that of the primary coil, and the induced voltage is input to the power supply circuit and the periodic signal generator. The power supply circuit converts the voltage induced in the trigger coil when the first half-wave voltage and the third half-wave voltage are induced in the primary coil of the ignition coil into a constant DC voltage, and converts the DC voltage to This is given to the power supply terminal of the microcomputer and the periodic signal generator. The periodic signal generation unit shapes and shapes the voltage induced in the primary coil of the ignition coil, whereby the rising and falling of each of the first half-wave voltage and the second half-wave voltage induced in the primary coil A rectangular wave signal in which a level change occurs is generated as a periodic signal, and this periodic signal is applied to the interrupt signal input terminal of the microcomputer. The microcomputer detects the rotational speed of the internal combustion engine from the generation period of the periodic signal (the time required for one rotation of the crankshaft), calculates the ignition timing of the engine with respect to the detected rotational speed, and calculates the calculated ignition When the timing is detected, the thyristor connected between the base emitters of the transistors constituting the current control switch is turned on to perform the ignition operation.

  In the ignition device disclosed in Patent Document 2, the trigger coil is omitted, and the voltage induced in the primary coil of the ignition coil is input to the power supply circuit and the periodic signal generator. The power supply circuit converts the first half-wave voltage and the third half-wave voltage induced in the primary coil of the ignition coil into a constant DC voltage and supplies the microcomputer with the power supply voltage. The periodic signal generation unit applies a rectangular wave-shaped periodic signal obtained by shaping the voltage induced in the primary coil to the interrupt signal input terminal of the microcomputer.

  Also in the ignition device disclosed in Patent Document 2, a current control switch is configured by a transistor in which a collector-emitter circuit is connected in parallel to the primary coil of the ignition coil, and the transistor is turned off between the base and emitter of the transistor. A thyristor is connected to The collector and base of the transistor are connected via a biasing resistor, and when the second half-wave voltage induced in the primary coil of the ignition coil reaches a predetermined level, the collector side of the transistor is changed to the base. A predetermined base current is supplied to turn on the transistor, and when the thyristor is turned on, the transistor is turned off to perform the ignition operation.

JP 2009-156203 A JP 2010-180854 A

  In the conventional current interruption type ignition device for an internal combustion engine shown in Patent Document 1 and Patent Document 2, induction is induced in the primary coil of the ignition coil both at the start of the engine and at the time of normal operation after completion of the start. Ignition operation by calculating the ignition timing of the engine with respect to the rotation speed of the engine detected using the periodic signal obtained by waveform shaping of the voltage, and turning off the current control switch at the calculated ignition timing Therefore, after starting the engine starting operation, the ignition operation could not be performed until the microcomputer was activated and the engine speed could be detected.

  In order to detect the rotational speed of the engine from the generation period of the periodic signal, the crankshaft needs to make one rotation. Therefore, in the case of the conventional ignition device, after starting the engine starting operation, the first ignition cannot be performed unless the crankshaft is rotated more than once, and the engine startability is improved. There was a problem of being damaged.

  In the current interruption type ignition device, since it is necessary to allow a large current to flow through the primary coil of the ignition coil, it is necessary to reduce the number of turns of the primary coil. Therefore, when the cranking rotation speed at the time of starting is low, the first half-wave voltage used to supply the microcomputer with the power supply voltage among the first to third half-wave voltages induced in the primary coil and the first half-wave voltage It becomes difficult to reach the peak value of the half-wave voltage of 3 to a level necessary for securing the power supply of the microcomputer, and it becomes difficult to maintain the microcomputer in the operating state. Therefore, the current interrupting ignition device in which the microcomputer is operated with the voltage induced in the primary coil of the ignition coil without controlling the battery and the ignition timing is controlled by the microcomputer is the cranking at the start. When the speed decreases, there is a problem that the ignition operation cannot be performed and the engine fails to start.

  In particular, when starting an engine using a starter that is operated manually, such as a recoil starter or a kick starter, the microcomputer is operated while the crankshaft rotates one or more times after starting the engine. Since it is difficult to continue to supply a voltage higher than the voltage value necessary for operation from the primary coil of the ignition coil to the power supply circuit, the probability of failure to start the engine increases with the conventional ignition device. It was inevitable.

  In addition to the ignition control unit using a microcomputer, it is conceivable to separately provide a circuit for detecting the timing to be ignited from the voltage across the primary coil of the ignition coil and turning off the current control switch. However, it is not preferable to use such a circuit in addition to the microcomputer because the structure of the ignition device becomes complicated.

  The object of the present invention is to enable the initial ignition operation without delay after the power supply voltage of the microcomputer is established, and to start the engine even when the engine is started by a starter operated by human power. An object of the present invention is to provide a current interrupting type ignition device for an internal combustion engine which can be easily performed.

According to the present invention, a primary coil and a secondary coil are provided on a stator of a magnet generator attached to an internal combustion engine, so that a negative first half wave, a positive second half wave, and a negative first 3 is connected in parallel to the ignition coil that induces an alternating voltage having a waveform in which three half-waves sequentially appear in the primary coil once during the rotation of the crankshaft of the internal combustion engine, and the primary coil of the ignition coil. A current control switch that is turned on when the second half-wave voltage is induced, and the secondary coil of the ignition coil is turned on when the current control switch is turned off from the on state. An ignition circuit that induces an ignition operation by inducing a high voltage for ignition, and an ignition control unit that controls on / off of the current control switch to control a timing (ignition timing) at which the ignition circuit performs an ignition operation For internal combustion engines Directed to a fire apparatus.

In order to achieve the above object, the present specification discloses at least the following first to tenth inventions.
1st invention In 1st invention disclosed by this specification, the primary current detection part which detects the primary current which flows through the primary coil of an ignition coil, and the information of the primary current detected by the said primary current detection part are obtained. A microcomputer that performs processing necessary to configure the ignition control unit, and converts the first half-wave voltage and the third half-wave voltage induced in the primary coil of the ignition coil into a DC voltage. And a power supply circuit for supplying the DC voltage to the microcomputer as a power supply voltage.

  In addition, the ignition control unit provides a switch driving means for providing a drive signal to the current control switch so that the current control switch can be turned on until the second half-wave voltage is induced in the primary coil. And a reference timing detection means for detecting, as a reference timing, a timing at which the primary current detected by the primary current detection unit reaches a threshold, and a waveform of the primary current detected by the primary current detection unit at the start of the internal combustion engine. A start point fire control means for obtaining a timing that can be used as an ignition timing at the start time as a start point fire timing, and immediately turning off the current control switch and performing an ignition operation in the ignition circuit when the start point fire timing is determined; Igniting the internal combustion engine with respect to the rotational speed information of the internal combustion engine obtained from the period in which the reference timing is detected after the start of the internal combustion engine is completed By calculating the period, and a normal ignition control means for causing an ignition operation in an ignition circuit by turning off state current control switch when detecting the calculated ignition timing.

  As described above, there is provided switch driving means for providing a drive signal to the current control switch until the second half-wave voltage is induced in the primary coil so that the current control switch can be turned on. In this case, when the second half-wave voltage is induced in the primary coil of the ignition coil at the time of starting the engine, the current control switch can be turned on to flow the primary current without causing a large delay. In addition, as described above, a timing that can be used as the ignition timing at the start of the internal combustion engine is obtained as a start timing fire timing from the waveform of the primary current detected by the primary current detector when the internal combustion engine is started, and the start timing fire timing is determined. If a starting point fire control means is provided that immediately turns off the current control switch to perform an ignition operation when it is obtained, the crankshaft rotates once and the engine speed is detected when the engine is started. Without waiting, the first ignition can be performed when the second half-wave (positive half-wave) voltage is first induced in the primary coil after the microcomputer is started. Therefore, after starting the engine starting operation, the engine can be started quickly and the engine can be started, and the cranking of the engine can be performed at a sufficient speed as in the case of starting the engine manually. Even if it is difficult to do so, the engine can be easily started.

  The current interruption type ignition device generates larger ignition energy as the current value when the primary current of the ignition coil is interrupted is larger. In the present invention, since the ignition timing is determined by monitoring the waveform of the primary current that is directly related to the magnitude of the ignition energy at the start of the engine, the initial ignition timing at the start of the engine is set as the ignition timing at the start. It is possible to determine the timing at which sufficient ignition energy can be obtained at the timing to obtain the engine, and to properly perform the initial explosion of the engine, thereby facilitating the start of the engine.

  In the first aspect of the invention, the reference timing detection means for detecting the timing at which the primary current of the ignition coil reaches the threshold value as the reference timing is provided in the ignition control unit constituted by a microcomputer, and the reference timing detection means Since the engine rotational speed information is obtained from the period at which the reference timing is detected, it is not necessary to separately provide a circuit for generating a crank signal that gives information on the crank angle of the engine. Therefore, according to the first invention, in addition to the ignition circuit configured by the ignition coil and the current control switch, the primary current detection unit, the microcomputer that configures the ignition control unit, and the power supply voltage to the microcomputer. It is possible to configure the ignition device simply by providing a power supply circuit for supplying the power, and to simplify the configuration of the ignition device.

Second Invention In the second invention disclosed in the present specification, a crank angle of an internal combustion engine using a primary current detector that detects a primary current flowing through the primary coil of the ignition coil and a voltage induced in the primary coil. Processing necessary for configuring an ignition control unit using a crank signal generation unit that generates a crank signal including information, primary current information detected by the primary current detection unit, and crank angle information given by the crank signal And a power supply circuit that converts the first half-wave voltage and the third half-wave voltage induced in the primary coil of the ignition coil into a DC voltage and supplies the DC voltage as a power supply voltage to the microcomputer And are provided.

  In the second invention, the ignition control unit can turn on the current control switch by supplying a drive signal to the current control switch until the second half-wave voltage is induced in the primary coil. And a timing that can be used as the ignition timing at the start of the internal combustion engine from the waveform of the primary current detected by the primary current detector at the start of the internal combustion engine. A starting point fire control means for performing an ignition operation by immediately turning off the current control switch when the timing is obtained, and the rotational speed information of the internal combustion engine obtained from the crank signal generation interval after the start of the internal combustion engine is completed With respect to the internal combustion engine, the ignition timing is determined, and when the determined ignition timing is detected, the ignition circuit is ignited by turning off the current control switch. And a constantly ignition control means.

  Even in this configuration, as in the case of the first aspect of the invention, after starting the engine starting operation, the engine can be started by promptly performing the initial explosion of the engine, and the engine can be started manually. Even in this case, it is possible to easily start the engine. In addition, since the ignition timing at the start of the engine is determined by monitoring the waveform of the primary current that is directly related to the magnitude of the ignition energy, sufficient ignition energy can be reliably obtained for the initial ignition timing at the start of the engine. It is possible to make sure that the first explosion of the engine is performed at a fixed time.

Third Invention The third invention is applied to the first invention or the second invention. In the present invention, the first half-wave voltage induced by the primary coil and the third half-wave The power supply circuit is configured to convert a voltage into a DC voltage and to supply the DC voltage to the microcomputer as a power supply voltage.

4th invention 4th invention is applied to 1st invention or 2nd invention, In this invention, an ignition coil is connected in series with respect to a primary coil, and is induced to this primary coil. An additional coil for inducing a voltage having the same phase as the voltage to be applied is provided on the primary side. In this case, the power supply circuit includes a voltage induced in the additional coil when the first half-wave voltage is induced in the primary coil and a voltage induced in the additional coil when the third half-wave voltage is induced in the primary coil. Is converted to a DC voltage.

Fifth Invention The fifth invention is applied to the first invention or the second invention. In the present invention, the timing at which the primary current detected by the primary current detector reaches the peak value is started. The starting point fire control means is configured to obtain the ignition timing.

Sixth Invention The sixth invention is also applied to the first invention or the second invention. In the present invention, the primary current detected by the primary current detector is set after the peak value has passed. The starting point fire control means is configured to obtain the timing when the level falls to the level as the starting point fire timing.

Seventh Invention The seventh invention is applied to the first invention or the second invention. In the present invention, the ignition control unit performs an ignition operation performed after starting the starting operation of the internal combustion engine. The ignition timing is controlled by the starting point fire control means until the number of times reaches the set number, and after the number of ignition operations performed after starting the internal combustion engine starting operation reaches the set number, it is normal The ignition timing is controlled by the hour ignition control means.

Eighth Invention The eighth invention is applied to the second invention. In the present invention, the crank signal generator receives an AC voltage induced in the primary coil of the ignition coil as an input, and the AC voltage The crank signal is generated at the timing when the first half wave of the waveform starts or when the waveform of the AC voltage shifts from the first half wave to the second half wave.

Ninth Invention The ninth invention is also applied to the second invention. In the present invention, the ignition coil includes an additional coil that is connected in series to the primary coil and induces a voltage having the same phase as the voltage induced in the primary coil on the primary side. In this case, the crank signal generation unit receives the voltage induced in the additional coil as an input, the timing at which the first half wave of the waveform of the AC voltage induced in the primary coil starts or the waveform of the AC voltage induced in the primary coil is the first. The crank signal is generated at the timing of transition from the first half wave to the second half wave.

Tenth Invention The tenth invention is applied to the first invention or the second invention. In the present invention, the primary current of the ignition coil is induced when the primary current of the ignition coil is cut off. In order to prevent the voltage from becoming excessive, primary induced voltage limiting means for limiting the voltage induced in the primary coil of the ignition coil when the current control switch is cut off to a set level or less is provided.

  According to the present invention, the first ignition can be performed when a positive half-wave voltage is first induced in the primary coil after the microcomputer is started when the engine is started. Therefore, after starting the engine starting operation, the engine can be started quickly without waiting for the crankshaft to make one revolution, as in the case of starting the engine manually. Even if it is difficult to crank the engine at a sufficient speed, the engine can be easily started.

  Further, according to the present invention, since the ignition timing at the start of the engine is obtained from the waveform of the primary current that is directly related to the magnitude of the ignition energy, when the engine is started, the ignition timing can be obtained with sufficient ignition energy. Therefore, it is possible to improve the engine starting performance.

  In particular, according to the first aspect of the present invention, the ignition control unit constituted by the microcomputer is provided with the reference timing detection means for detecting the timing at which the primary current of the ignition coil reaches the threshold as the reference timing. Since the engine rotational speed information necessary for calculating the ignition timing in the normal operation after the completion of the engine start is obtained from the period in which the engine is detected, a signal for obtaining the engine rotational speed information is generated. The hardware circuit can be omitted, and the configuration of the ignition device can be simplified.

It is the block diagram which showed the structure of one Embodiment of this invention. It is the front view which showed the example of the structure of the principal part of the magnet generator used by embodiment shown in FIG. FIG. 2 is a circuit diagram illustrating a configuration example of hardware of the embodiment illustrated in FIG. 1. It is the block diagram which showed the structure of other embodiment of this invention. FIG. 5 is a circuit diagram illustrating a configuration example of hardware of the embodiment illustrated in FIG. 4. It is the block diagram which showed the structure of other embodiment of this invention. FIG. 7 is a circuit diagram illustrating a hardware configuration example of the embodiment illustrated in FIG. 6. It is the block diagram which showed the structure of other embodiment of this invention. FIG. 9 is a circuit diagram illustrating a hardware configuration example of the embodiment illustrated in FIG. 8. 5 is a time chart schematically showing voltage and current waveforms of respective parts of the embodiment shown in FIG. 1 and the embodiment shown in FIG. 4. FIG. 9 is a time chart schematically showing voltage and current waveforms of respective parts of the embodiment shown in FIG. 6 and the embodiment shown in FIG. 8. FIG. It is the flowchart which showed an example of the algorithm of the main routine of the process which a microcomputer performs in each embodiment of this invention. 13 is a flowchart illustrating an example of an algorithm for a memory initialization process performed in the main routine illustrated in FIG. 12. It is the flowchart which showed an example of the algorithm of the starting A / D process performed at the time of engine starting in each embodiment. 5 is a flowchart illustrating an example of an algorithm of a reference timing interrupt process executed every time the reference timing detection unit detects a reference timing in the embodiment of FIG. 1 and the embodiment of FIG. 5 is a flowchart showing an algorithm of processing executed when the time when the timer X is set is measured in the embodiment of FIG. 1 and the embodiment of FIG. 4. It is the flowchart which showed the algorithm of the process performed when the measurement of the time when the ignition timer was set in each embodiment was completed. In the embodiment shown in FIG. 6 and the embodiment shown in FIG. 8, an algorithm of processing executed when a crank signal is input to the interrupt input terminal of the microcomputer when the first half-wave voltage is generated is shown. It is a flowchart.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention can be applied to an ignition device for igniting a two-cycle internal combustion engine and an ignition device for igniting a four-cycle internal combustion engine. However, in the embodiment shown below, the internal combustion engine to be ignited is a four-cycle engine. Suppose there is.

[First Embodiment]
FIG. 1 is a block diagram showing the configuration of the first embodiment of the present invention. In FIG. 1, 1 is a magnet generator attached to an internal combustion engine (not shown). The magnet generator 1 includes a primary coil Wp and a secondary coil Ws of an ignition coil IG on an iron core having a three-pole magnet rotor attached to a crankshaft of an internal combustion engine and a magnetic pole portion facing the magnetic pole of the magnet rotor. 10B and 11B, as schematically shown in FIGS. 10B and 11B, the first half-wave voltage V1 and the second half-wave voltage are included. An AC voltage having a waveform in which V2 and a third half-wave voltage V3 appear in sequence is induced in the primary coil Wp only once during one revolution of the crankshaft of the internal combustion engine.

  Of the first to third half-wave voltages induced in the primary coil Wp of the ignition coil, the first half-wave voltage V1 and the third half-wave voltage V3 have negative polarity with relatively low peak values. The second half-wave voltage V2 is a positive voltage having a peak value higher than that of the first half-wave voltage and the third half-wave voltage. In the current interruption type ignition device, the second half-wave voltage V2 having a high peak value is used to obtain ignition energy.

  Referring to FIG. 2, a main part of a configuration example of the magnet generator 1 is shown. A magnet generator 1 shown in FIG. 2 includes a magnet rotor 1a attached to an engine crankshaft (not shown) and a stator 1b fixed to an engine case (not shown). It consists of. The magnet rotor 1a has a cup-shaped flywheel 101 attached to the crankshaft of the engine and an arc-shaped permanent magnet fixed in a recess 102 formed on the outer periphery of the flywheel and magnetized in the radial direction of the flywheel. It consists of a magnet 103. In the illustrated magnet rotor, the magnetic pole on the outer peripheral side of the permanent magnet 103 (N pole in the illustrated example) and the magnetic pole on the inner peripheral side of the permanent magnet led to the outer peripheral surface of the flywheel located on both sides of the recess 102. (In the example shown, S pole) constitutes a (three pole) magnet field having three magnetic poles arranged in the circumferential direction of the flywheel.

  The stator 1b includes a rod-shaped main iron core 104 made of a laminate of steel plates, and a pair of yokes 105 and 106 each having a rear end portion fixed to one end and the other end of the main iron core 104 in the longitudinal direction. A character-shaped iron core 107 and an ignition coil IG wound around the main iron core 104 are provided. Magnetic pole portions 108 and 109 having cylindrical magnetic pole surfaces are formed at the tips of the yokes 105 and 106, and these magnetic pole portions are opposed to the outer peripheral surface of the magnet rotor via a gap.

  The ignition coil IG includes a primary coil Wp wound around a primary bobbin 110 fixed to the iron core main part 104, and a secondary coil Ws wound around a secondary bobbin 111, and the secondary coil is wound. The secondary bobbin 111 thus fitted is fitted on the outer periphery of the primary coil Wp. Outside the secondary coil Ws, an ignition unit 113 configured by mounting elements necessary for controlling the current flowing through the primary coil Wp of the ignition coil on the printed circuit board 112 is disposed. The ignition unit 113 and the primary coil Wp are arranged. Are connected via a conductor 114. The ignition coil IG and the ignition unit 113 are inserted into a resin case 115, and the ignition coil IG and the ignition unit 113 are molded by casting a thermosetting insulating resin in the case 115. . The high voltage cord 116 is led out from the non-grounded terminal of the secondary coil Ws of the ignition coil, and a high voltage for ignition induced in the secondary coil Ws is supplied through the high voltage cord 116 to the ignition plug attached to the cylinder of the engine. The

  In the example shown in the drawing, the ignition coil IG, the ignition unit 113, and the case 115 for housing them constitute a current interrupting type ignition device IU for an internal combustion engine. The ignition device IU is arranged with the magnetic pole portions 108 and 109 of the iron core 107 opposed to the outer peripheral surface on which the magnetic poles of the magnet rotor are formed with a predetermined gap therebetween, and the yoke of the iron core 107 of the ignition coil IG. The iron core 107 is fastened to a stator mounting portion provided in an engine case or the like by bolts passing through mounting holes h1 and h2 formed in 105 and 106, respectively, thereby being fixed to the case of the internal combustion engine. The

  When the crankshaft of the internal combustion engine rotates and the magnet rotor 1a of the magnet generator 1 shown in FIG. 2 rotates, the three magnetic poles of the field SNS of the magnet rotor 1a are the magnetic pole portions of the iron core 107 of the stator. When passing through the positions 108 and 109, the magnetic flux φ flowing through the iron core 107 alternates as shown in FIGS. 10 (A) and 11 (A), and the change in this magnetic flux causes the primary coil Wp of the ignition coil to As shown in FIGS. 10 (B) and 11 (B), an AC voltage having a waveform in which a first half-wave voltage V1, a second half-wave voltage V2, and a third half-wave voltage V3 appear in order. Induces. An alternating voltage is also induced in the secondary coil Ws by the alternating magnetic flux φ, but the voltage induced in the secondary coil Ws reaches a voltage that causes a spark discharge in the spark plug before the primary current flowing in the primary coil Wp is cut off. Therefore, the ignition operation is not performed by the secondary voltage.

  As shown in FIG. 1, a current control switch 2 is connected in parallel to the primary coil Wp of the ignition coil IG, and the ignition circuit 3 is configured by the ignition coil IG and the current control switch 2. . The current control switch 2 is a semiconductor switch such as an insulated gate transistor (IGBT), a bipolar transistor, or a field effect transistor (MOSFET) that can be controlled on and off. It is turned on when a half-wave voltage is induced.

  When the current control switch 2 is turned on, the primary current I1 flows from the primary coil Wp through the current control switch 2. The current control switch 2 is turned off at the ignition timing of the internal combustion engine by an ignition control unit 10 to be described later. When the current control switch 2 is turned off, a high-polarity voltage that induces the primary current I1 that has been flowing until then is induced in the primary coil Wp. Since this voltage is boosted by the step-up ratio between the primary and secondary of the ignition coil, a high voltage for ignition of 20 to 30 [kV] is induced in the secondary coil Ws of the ignition coil. Since the high voltage induced in the secondary coil Ws is applied to the spark plug 4 attached to the cylinder of the internal combustion engine, spark discharge occurs in the discharge gap of the spark plug 4 and the engine is ignited.

  In the present invention, a microcomputer (not shown in FIG. 1) is provided to configure the ignition control unit 10. The microcomputer executes a program for performing processing for controlling the ignition timing of the internal combustion engine (timing for turning the current control switch 2 from the on state to the off state). In order to operate the microcomputer, it is necessary to apply a DC voltage Vcc having a predetermined voltage value (usually 5 [V]) to the power supply terminal of the microcomputer.

  In the internal combustion engine ignition device according to the present invention, the first half-wave voltage V1 for inducing a DC power source for maintaining the microcomputer constituting the ignition control unit 10 in an operating state to the primary coil Wp of the ignition coil; Obtained from the third half-wave voltage V3. Therefore, in the present embodiment, the first half-wave voltage V1 and the third half-wave voltage V3 induced in the primary coil Wp are converted into a constant (usually 5 [V]) DC voltage Vcc. A power supply circuit 5 for supplying the DC voltage Vcc to the power supply terminal of the microcomputer is provided. The power supply circuit 5 includes, for example, a first capacitor that is charged to a constant voltage with a negative first half-wave voltage V1 and a third half-wave voltage V3 that are induced in the primary coil Wp, and the first capacitor And a pumping circuit that shifts the charge accumulated in the capacitor to the second capacitor and generates a DC voltage having a polarity obtained by inverting the voltage at both ends of the first capacitor at both ends of the second capacitor. .

  In the present embodiment, there is also provided a primary current detector 6 that detects the primary current I1 flowing through the current control switch 2 and supplies information of the detected primary current to the A / D input terminal of the microcomputer. For example, the primary current detector 6 is connected in series with the current control switch 2 and the primary coil Wp so that the primary current I1 flows, and when the primary current I1 flows, the primary current detector 6 sets the current value of the primary current. It can be constituted by a current limiting element that produces a proportional voltage drop at both ends. As the current limiting element constituting the primary current detection unit 6, a shunt resistor, a diode array configured by connecting a plurality of diodes in the same direction in series, or the like can be used. The primary current detection unit 6 can also be configured by a hall current sensor or the like.

  The ignition control unit 10 constituted by a microcomputer includes a switch drive unit 11, a reference timing detection unit 12, a starting point fire control unit 13, and a normal point fire control unit 14. These means will be described below.

Switch driving means 11
The switch driving means 11 gives a drive signal to the current control switch until the positive second half-wave voltage V2 is induced in the primary coil Wp so that the current control switch can be turned on. It is a means to put. When the microcomputer starts the engine operation and the power supply circuit 5 generates a voltage necessary for starting the microcomputer, after resetting each part such as a memory and a timer (after power-on reset) First, when a second half-wave voltage is applied from the primary coil Wp to the current control switch 2 by applying a drive signal to the control terminal of the current control switch 2, the current control switch is immediately turned on. Keep it. After the microcomputer performs power-on reset, the switch driving means 11 is constituted by a process of applying a drive signal to the current control switch 2.

Reference timing detection means 12
The reference timing detection means 12 is a means for detecting a reference timing used as a timing for detecting the rotational speed of the internal combustion engine and a timing for starting measurement of the ignition timing of the engine. As shown in FIG. 10D, the reference timing detection means 12 detects a timing tc at which the primary current I1 detected by the primary current detector 6 reaches the threshold value Ith as a reference timing. The microcomputer reads the primary current information given from the primary current detector 6 to the A / D input terminal at a minute time interval, compares the read primary current information with a threshold value, and the read primary current information exceeds the threshold value. Is detected as a reference timing. Since the waveform of the primary current I1 changes with a constant correlation with the crank angle of the engine (crankshaft rotation angle position), at the reference timing tc, the crank angle position of the engine is a constant position (reference crank angle). Timing).

Start-up fire control means 13
The starting point fire control means 13 obtains a timing that can be used as the ignition timing at the start of the internal combustion engine from the waveform of the primary current detected by the primary current detector 6 at the time of starting the internal combustion engine as a starting point fire timing. This is a means for performing the process of turning off the current control switch 2 immediately when the timing is obtained (the process of removing the drive signal applied to the current control switch 2) and causing the ignition circuit to perform an ignition operation. . If the ignition timing at the start of the internal combustion engine is too advanced relative to the timing at which the piston of the engine reaches top dead center, the piston will be pushed back without exceeding the top dead center when the engine is ignited. Not only does it fail to start the engine, but also the driver operating the starter is impacted, which is not preferable. The phenomenon in which the piston is pushed back without being able to exceed top dead center when the engine is ignited is called ketchin or kickback.

  In order to prevent kickback from occurring at the start of the engine, the timing that can be used as the ignition timing at the start of the internal combustion engine is a position that is not advanced too much with respect to the timing when the crankshaft of the engine reaches top dead center. In addition, this is the timing at which a sufficient cut-off current value (a value of the primary current when the current control switch 2 is turned off to cut off the primary current) to obtain energy for igniting the engine is obtained. Since the waveform of the primary current I1 changes with a constant correlation with the crank angle of the engine, if the ignition timing at the start is determined based on the waveform of the primary current, it is suitable for the start of the engine as the ignition position at the start Ignition can be performed at a different crank angle position.

  For example, when the rotational angle position of the crankshaft of the internal combustion engine reaches a position where the piston of the engine reaches the top dead center (top dead center position) or a position slightly advanced from the top dead center position, the primary current I1 It is assumed that the stator 1b of the magnet generator is arranged so that reaches the peak. In this case, the crank angle position that can be used as the ignition position at the start of the engine is, for example, the position where the primary current I1 reaches the peak or the energy necessary to ignite the engine after the primary current I1 passes the peak. This is the crank angle position when the current cut-off value is lowered to a set level that is set so as not to fall below the minimum value of the current cutoff value that is allowed to obtain.

  In the above case, the starting point fire control means 13 is configured to obtain the timing at which the primary current detected by the primary current detector 6 reaches the peak value as the starting point fire timing, or detected by the primary current detector 6. The timing when the primary current that has been reduced to a set level after passing the peak value is determined as the starting ignition timing.

Normal point fire control means 14
The normal point fire control means 14 calculates the ignition timing of the internal combustion engine with respect to the rotational speed information of the internal combustion engine obtained from the period in which the reference timing is detected by the reference timing detection means 12 after the start of the internal combustion engine is completed. When the calculated ignition timing is detected, the current control switch is turned off to cause the ignition circuit 3 to perform an ignition operation.

  In the example shown in FIG. 1, the normal time point fire control means 14 is composed of a rotational speed calculation means 14A, a normal time point fire timing calculation means 14B, a normal time point fire timing detection means 14C, and a switch-off means 14D. Yes.

  Here, each time the reference timing detection unit 12 detects the reference timing (the timing at which the primary current reaches the threshold), the rotation speed calculation unit 14A detects the current reference timing from the time when the previous reference timing was detected. This is a means for calculating the rotational speed of the engine from the time until (the time required for one rotation of the crankshaft).

  Further, the normal time-of-fire timing calculation means 14B is a means for calculating the ignition timing of the engine at the rotation speed calculated by the rotation speed calculation means 14A. This normal point fire timing calculation means searches the ignition timing calculation table (map) that gives the relationship between the rotation speed and the ignition timing with respect to the rotation speed calculated by the rotation speed calculation means 14A, and the searched value Is subjected to an interpolation calculation to calculate the ignition timing of the engine at the calculated rotational speed. The normal ignition timing calculation means 14B calculates the ignition timing with respect to the calculated rotation speed every time the rotation speed is calculated at the reference timing, and stores the calculated ignition timing in the RAM of the microcomputer.

  When the reference timing is detected, the normal time-of-fire timing detection means 14C causes the ignition timer in the microcomputer to measure the ignition timing calculated at the previously detected reference timing and stored in the RAM. The time is calculated as the ignition timing measurement time, the calculated ignition timing measurement time is immediately set in the ignition timer, and the measurement is started. The normal time ignition timing detection means 14C uses the timing when the measurement of the ignition timing measurement time when the ignition timer is set as the ignition timing, and gives a switch-off command to the switch-off means 14D when the ignition timing is detected. The switch-off means 14D is a process for turning off the current control switch 2 at the timing when the switch-off command is given from the normal-time-fire-timing detection means 14C (removes the drive signal given to the current control switch 2). The current control switch 2 is turned off.

  Referring to FIG. 3, a hardware configuration example of the internal combustion engine ignition device shown in FIG. 1 is shown. In the example shown in the figure, the current control switch 2 is constituted by an IGBT (insulated gate transistor) T1 having a collector connected to the non-grounded terminal of the primary coil Wp of the ignition coil.

  Further, a shunt resistor Rs is connected between the emitter of the IGBT T1 and the ground side terminal of the primary coil Wp, and the primary current detector 6 is configured by this shunt resistor. Since the shunt resistor Rs is connected in series with the primary coil Wp and the current control switch 2, when the primary current I1 flows from the primary coil of the ignition coil through the current control switch 2, the shunt resistor Rs A voltage drop proportional to the primary current I1 occurs at both ends. The voltage across this resistor Rs is used as the primary current detection signal. The ground side terminal of the primary coil Wp is grounded together with the ground side terminal of the secondary coil Ws.

  The power supply circuit 5 includes a diode D1 having an anode connected to the ground-side terminal of the primary coil Wp, a first capacitor C1 having one end connected to the cathode of the diode D1, and an anode connected to the other end of the capacitor. A diode D2 having a cathode connected to the non-ground side terminal of the primary coil Wp, a diode D3 having an anode connected to a connection point between the capacitor C1 and the diode D1, and a first connected between the cathode of the diode D3 and the ground. 2 capacitor C2, a Zener diode ZD whose anode is connected to the ground side at both ends of the second capacitor C2, and a resistor connected in parallel to the series circuit of the diode D1 and the second capacitor C1. And R1. Charges temporarily accumulated in the first capacitor C1 are transferred to the second capacitor by the diodes D1 to D3, the first and second capacitors C1 and C2, and the resistor R1, and the second capacitor C2 is charged. Thus, a pump circuit for obtaining a voltage having a polarity opposite to the voltage at both ends of the first capacitor C1 is formed at both ends of the second capacitor C2.

  In the illustrated power supply circuit 5, when a negative first half-wave voltage V1 and a third half-wave voltage V3 are induced in the primary coil Wp, the first capacitor C1 is illustrated through the diodes D1 and D2. Charged to the polarity. Since the charge accumulated in the first capacitor C1 is transferred to the second capacitor C2 through the diode D3 and the resistor R1, the second capacitor C2 is charged to the polarity shown in the figure. The voltage across the second capacitor C2 is limited by the Zener voltage of the Zener diode ZD. A Zener diode ZD having a Zener voltage equal to the power supply voltage (5 [V]) of the microcomputer is used.

  In FIG. 3, the MCU is a microcomputer constituting the ignition control unit 10. The microcomputer MCU includes a CPU, a memory such as a ROM and a RAM, a timer, and the like, and constitutes various function realizing means by executing programs stored in the ROM. The microcomputer MCU includes a power supply terminal to which a power supply voltage Vcc is applied from the power supply circuit 5, an output port A for supplying a drive signal to the current control switch, and an A / D input port for inputting an analog signal. Primary current detection signals obtained at both ends of the resistor Rs of the primary current detection unit 6 are input to the A / D input port.

  Next, the operation of the internal combustion engine ignition device shown in FIG. 1 will be described with reference to FIG. FIG. 10A shows the change of the magnetic flux φ flowing through the iron core of the ignition coil, and FIG. 10B shows the voltage VL induced in the primary coil Wp. FIG. 10C shows the power supply voltage Vcc supplied from the power supply circuit 5 to the microcomputer, and FIG. 10D shows the primary current I1. FIG. 10E shows the timing operation of the ignition timer in the microcomputer. FIGS. 10F and 10G show the timing operation of the timer for determining the timing for turning on the IGBT T1 and the output port A of the microcomputer. To the voltage applied to the gate of the IGBT.

  When the start operation of the internal combustion engine is performed, the crankshaft of the engine rotates, so that a change as shown in FIG. 10A occurs in the magnetic flux φ flowing through the iron core of the ignition coil, and this change in the magnetic flux causes the primary coil Wp to An AC voltage VL (FIG. 10B) having a waveform in which a negative first half-wave voltage V1, a positive second half-wave voltage V2, and a negative third half-wave voltage V3 appear in order. Induce. In FIG. 10, the time when the first half-wave voltage V1 of the AC voltage VL is generated and the time when it becomes zero (the time when the second half-wave voltage is generated) are t1 and t2, respectively. The time when the wave voltage is generated (time when the second half-wave voltage is zero) and the time when the third half-wave voltage is zero are t3 and t4, respectively.

  Since the first half-wave voltage V1 and the third half-wave voltage V3 of the AC voltage VL are input to the power supply circuit 5, the power supply circuit 5 gives the power supply voltage Vcc (FIG. 10C) to the microcomputer MCU. The power supply voltage Vcc decreases at a constant rate after reaching the peak value (5 V) while the first half-wave voltage is generated, but again when the third half-wave voltage V3 is generated. After the third half-wave voltage has risen and passed the peak, it decreases at a constant rate until the next first half-wave voltage V1 is generated. After the engine is started, when the peak values of the first half-wave voltage V1 and the third half-wave voltage V2 increase and the interval at which the AC voltage VL is generated becomes shorter, the power supply voltage Vcc becomes the zener diode. A value (5 V) equal to the Zener voltage of ZD is maintained.

  After the engine is started, when the power supply voltage Vcc reaches the minimum voltage Vth necessary for operating the microcomputer at time ta, the microcomputer MCU is activated to perform a power-on reset. When the rated value of the power supply voltage Vcc of the microcomputer is 5 [V], the minimum voltage Vth necessary for operating the microcomputer is about 2.3 [V]. The microcomputer is maintained in the operating state while the power supply voltage Vcc is maintained at the minimum value Vth or more.

  In the example shown in FIG. 10, the timing at which the power supply voltage Vcc output from the power supply circuit 5 reaches the peak and the first half-wave voltage and the third half-wave voltage induced in the primary coil Wp reach the peak. However, when the power supply circuit 5 is constituted by a pump circuit as shown in FIG. 3, the timing at which the power supply voltage Vcc reaches the peak value at the start of the engine is the first half wave of the primary voltage VL. And the timing at which the third half-wave voltage reaches a peak are slightly delayed.

  In the example shown in FIG. 10, the microcomputer MCU starts at time ta and performs a reset operation such as initialization of the memory. Then, as shown in FIG. 10G, the microcomputer starts from the output port A to the IGBT T1. A drive signal is applied between the gate and the emitter. The voltage value of this drive signal is almost the same as the voltage value of the power supply voltage Vcc of the microcomputer. As a result, the IGBT T1 can be turned on (a state in which the IGBT T1 is turned on immediately when a forward voltage higher than the threshold value is applied between the collector and the emitter). Therefore, after the second half-wave voltage V2 of the AC voltage VL rises at time t2, when the threshold value is reached at time tb, the IGBT T1 is turned on and the primary current I1 starts to flow through the ignition coil.

  Next, the microcomputer MCU detects the time tc when the primary current I1 reaches the threshold value Ith from the primary current detection signal input to the A / D terminal from the primary current detector 6 as a reference timing. The reference timing detection means 12 is configured by the process in which the microcomputer detects the reference timing tc.

  The microcomputer also obtains a timing that can be used as the ignition timing at the start of the internal combustion engine from the waveform of the primary current detected by the primary current detector 6 as a start timing fire timing, and immediately determines the start timing fire timing. The control switch (IGBT in this embodiment) 2 is turned off to cause the ignition circuit to perform an ignition operation.

  In the example shown in FIG. 10, the primary current detection signal input from the primary current detection unit 6 to the A / D terminal is sampled every minute time, and the newly sampled primary current value is sampled immediately before. The timing td at which the primary current I1 has the maximum value is obtained as the starting ignition timing, and at the starting ignition timing td, as shown in FIG. 10 (G), the port A is connected to the gate of the IGBT T1. The given drive signal is set to zero. As a result, the IGBT T1 is turned off at the ignition timing td at the starting time, and the primary current I1 that has been flowing through the ignition coil until then is cut off to perform the ignition operation.

  The starting point fire control means 13 is configured by the process of obtaining the starting point fire timing as described above and performing the ignition operation with the IGBT turned off at the obtained starting point fire timing. When the ignition timing control means 13 at the starting time performs an ignition operation at the end of the compression stroke of the engine, the first explosion of the engine is performed and the engine is started.

  The microcomputer also sets a predetermined time to a timer X (on timing determination timer) that performs a time measuring operation for determining the next timing of supplying the drive signal to the IGBT when the time tc is detected as the reference timing, The time measurement is started as shown in FIG. When the timer X completes the time measuring operation at time te, a drive signal is applied from the port A of the microcomputer to the gate of the IGBT so that the IGBT can be turned on.

  The time to be measured by the timer X is set so that the timer completes the time measuring operation after the primary coil Wp induces the voltage of the third half wave. After the engine start operation is started and until the engine rotation speed is detected, the time to be measured by the timer X is set to a fixed time set based on the predicted value of the rotation speed of the crankshaft at the start. Set it. After the rotational speed of the engine is detected, the timer X is caused to measure the time calculated based on the rotational speed of the engine.

  After the start operation is started, the switch driving means 11 is provided by a process of supplying a drive signal to the IGBT when the microcomputer is started and a process of supplying a drive signal from the port A of the microcomputer to the gate of the IGBT when the timer X completes the time measuring operation. Is configured.

  As described above, until the start of the engine is completed, a timing that can be used as an ignition timing at the start of the internal combustion engine is determined as a start timing fire timing from the waveform of the primary current detected by the primary current detector 6. Ignition operation is performed at the starting timing. If the ignition timing at the start of the internal combustion engine is too advanced with respect to the timing at which the piston of the engine reaches top dead center, the piston may not exceed top dead center and a kickback may occur. In order to prevent kickback, a magnet is installed in the engine so that the timing at which the second half-wave voltage of the AC voltage induced in the primary coil reaches a peak does not advance too much relative to the timing at which the piston reaches top dead center. Install a generator.

  After the start of the internal combustion engine is completed, the ignition timing is controlled by the normal time fire control means 14. Whenever the reference timing tc is detected, the normal time point fire control means rotates the internal combustion engine from the period (time required for one rotation of the crankshaft) that the rotation speed calculation means 14A detects the reference timing tc. The speed is calculated, the normal time fire timing calculation means 14B calculates the normal time fire timing of the internal combustion engine with respect to the calculated rotation speed, and the calculated ignition timing is stored in the memory. In addition, when the reference timing tc is detected, the normal time ignition timing detection means 14C reads the normal time ignition timing calculated and stored at the previous reference timing and detects the read normal time ignition timing. The time to be measured by the ignition timer (ignition timing measurement time) is calculated, the calculated ignition timing measurement time is set in the ignition timer, and the measurement is started. When the ignition timer completes the timing operation (when detecting the normal time ignition timing), the normal time ignition timing detection unit 14C gives a switch-off command to the switch-off unit 14D to stop the supply of the drive signal to the IGBT. . As a result, the IGBT is turned off to perform the ignition operation.

  The detection of the completion of the start of the internal combustion engine is, for example, the normal ignition timing of the engine after starting the start operation of the internal combustion engine (ignition timing at the end of the compression stroke performed once while the crankshaft rotates twice). This can be done because the number of ignition operations performed in (1) has reached the set number (at least once). The ignition control unit 10 controls the ignition timing by the start point fire control means 13 until the ignition operation is started a predetermined number of times after starting the start operation of the internal combustion engine, and the start operation of the internal combustion engine is controlled. The ignition timing can be controlled by the normal point fire control means 14 after the number of ignitions performed at the regular ignition timing after the start reaches the set number. In the present embodiment, for the sake of simplicity, it is assumed that the start of the engine is completed when the ignition is performed once at the normal ignition timing after the start operation of the engine is started.

  In a four-cycle internal combustion engine, an ignition operation performed at the end of a compression stroke (including a certain period immediately after the piston passes the top dead center) that is performed once while the crankshaft rotates twice rotates the engine. In this embodiment, the ignition operation is performed every time the crankshaft makes one rotation. Therefore, the ignition operation is performed even at the end of the exhaust stroke, but the ignition operation performed in the exhaust stroke does not affect the operation of the engine.

  In this embodiment, flowcharts showing the algorithm of the program executed by the microcomputer to configure the ignition control unit 10 are shown in FIGS. FIG. 12 shows an example of the main routine algorithm executed by the microcomputer. In the case of this algorithm, first, the microcomputer is powered on and reset in step S101, and the memory initialization process shown in FIG. 13 is performed in step S102.

  In the memory initialization process shown in FIG. 13, a timer for measuring elapsed time is started in step S201, and the count value and flag of each timer other than the timer for timer in the microcomputer are reset in step S202. Next, in step S203, necessary memory is initialized, and in step S204, a drive signal is given between the gate and emitter of the IGBT T1 constituting the current control switch so that the current control switch can be turned on. In S205, the process returns to the main routine.

  When the memory initialization process is completed and the routine returns to the main routine of FIG. 12, the watchdog timer provided in the microcomputer is cleared in step S103, and whether or not the engine has been started in step S104 (start start flag). Whether or not is set). If it is determined in step S104 that the engine has not been started (the start end flag has not been set), the process proceeds to step S105 to perform the start A / D process shown in FIG.

  In the starting A / D process, in step S301, it is determined whether or not the detected value of the primary current input from the primary current detection unit 6 to the A / D input port of the microcomputer exceeds the peak value, and the primary current is detected. When the detected value does not exceed the peak value, it waits for the peak value to be exceeded. When it is determined in step S301 that the detected value of the primary current has exceeded the peak value, the process proceeds to step S302 to set the drive signal applied to the gate of the IGBT T1 to zero and turn off the IGBT. In step S303, the start end flag is set. set. After setting the start / end flag, the process returns to the main routine in step S304.

  After returning from the start A / D process to the main routine, the watchdog timer is cleared in step S103, and it is determined in step S104 whether the start end flag is set. At this time, since it is determined that the start / end flag is set, the process proceeds to step S106, and it is determined whether or not the calculation start flag is set. As a result, if it is determined that the calculation start flag is not set, the process returns to step S103. If it is determined in step S106 that the calculation start flag is set, the process proceeds to step S107, and an ignition timing calculation table used for calculation of the ignition timing is selected. The ignition timing calculation table is a table that gives the relationship between the engine rotational speed and the ignition timing, and a plurality of tables that give various characteristics of the engine are experimentally created and stored in the ROM. The ignition timing calculation table is searched for the engine rotational speed separately detected in step S108, the ignition timing at a rotational speed close to the detected rotational speed is read from the table, and interpolation calculation is performed on the read ignition timing. By applying, the ignition timing of the engine is calculated.

  After calculating the ignition timing in step S108, in step S109, a timer set value (ignition timing measurement time) to be set in the ignition timer is calculated, and the process returns to step S103. The ignition timing measurement time set in the ignition timer is the time for the ignition timer to measure from when the reference timing is detected until the ignition operation is performed.

  The microcomputer also determines whether or not the detection value of the primary current I1 given from the primary current detector 6 has reached the threshold value Ith, and detects the timing at which the primary current reaches the threshold as the reference timing. Each time the reference timing is detected by the detection means, the process being executed is interrupted, and the reference timing interrupt process shown in FIG. 15 is executed. In this process, the measurement value of the timer for timekeeping is read in step S401, and the reference timing is detected by calculating the difference between the measurement value of the timer read this time and the measurement of the timer read when the previous reference timing was detected. The time indicating the cycle (the time from when the previous reference timing is detected until the current reference timing is detected) is measured as the cycle time, and the time measurement timer is restarted. Also, the engine speed is calculated from the period time (time required for one rotation of the crankshaft).

  Next, in step S402, a timer set value is set in the timer X that measures the time for obtaining the next timing to turn on the IGBT T1. This timer set value is set to such a value that the timer X completes the timing operation after the third half wave V3 of the AC voltage induced in the primary coil Wp disappears.

  Next, after setting the ignition timing measurement time in the timer in the microcomputer used as the ignition timer in step S403, the calculation start flag is set in step S404, and in step S405, an interrupt for shifting to the reference timing interrupt process is applied. Return to the process that was being executed.

  The microcomputer also executes a timer X interrupt process shown in FIG. 16 when the measurement of the time when the timer X is set is completed. In this timer X interrupt process, in step S501, a drive signal is supplied to the IGBT T1 so that the IGBT can be turned on, and the next reference timing interrupt is permitted. Then, in step S502, the timer X interrupt process is performed. Return to the process that was executed when moving to.

  The microcomputer also executes the ignition timer interruption process shown in FIG. 17 when the measurement of the ignition timing measurement time in which the ignition timer is set is completed (when the ignition timing calculated with respect to the rotation speed is detected). In this interrupt process, after the drive signal applied to the IGBT T1 in step S601 is removed and the ignition operation is performed by turning off the IGBT, the process proceeds to this interrupt process in step S602. Return to the process that was being executed.

  When the ignition control unit 10 is configured by the algorithm shown in FIGS. 12 to 17, the switch drive unit 11 is configured by the memory initialization process of step S <b> 204 of FIG. 13 and the timer X interrupt process of FIG. 16. Further, the starting point fire control means 13 is configured by the starting A / D process shown in FIG. 14, and the normal point fire control means 14 is formed by the reference timing interruption process shown in FIG. 15 and the ignition timer interruption process shown in FIG. Is configured.

  Of the normal point fire control means 14, the rotation speed calculation means 14A is constituted by step S401 of the interrupt process of FIG. 15, and the normal point fire timing calculation means 14B is constituted by steps S107 and S108 of the main routine of FIG. Is done. Further, the normal point fire timing detection means 14C is configured by step S403 of the interrupt process in FIG. 15, and the switch-off means 14D is configured by the ignition timer interrupt process in FIG.

  As in the above-described embodiment, a drive signal is applied to the current control switch 2 until the second half-wave voltage V2 is induced in the primary coil Wp so that the current control switch can be turned on. If the switch driving means 11 is provided, the current control switch 2 is turned on without causing a large delay when the second half-wave voltage V2 is induced in the primary coil of the ignition coil when the engine is started. Since the current can flow, the time during which the primary current flows can be lengthened, and the ignition operation can be performed by cutting off the primary current during the period in which the primary coil Wp generates the second half-wave voltage. The proportion of the period that can be performed can be increased, and the variable range of the ignition timing of the engine can be widened.

  Further, as in the above-described embodiment, the timing that can be used as the ignition timing at the start of the internal combustion engine is determined as the start timing fire timing from the waveform of the primary current detected by the primary current detector 6 at the start of the internal combustion engine, When the start point fire control means 13 is provided to perform the ignition operation by immediately turning off the current control switch 2 when the fire timing is obtained, when the engine is started, the crankshaft makes one rotation and the engine speed The first ignition can be performed when the second half-wave voltage V2 is first induced in the primary coil Wp after the microcomputer is started up without waiting for the detection. Therefore, after starting the engine starting operation, the first explosion of the engine can be carried out promptly and the engine can be reliably started, and the cranking of the engine can be sufficiently performed as in the case of starting the engine manually. Even if it is difficult to perform at a speed, the engine can be easily started.

  In the above embodiment, when starting the engine, the starting point fire control means 13 determines the ignition timing by monitoring the waveform of the primary current directly related to the magnitude of the ignition energy. By setting the initial ignition timing at a timing that can be used as the ignition timing at the start, and at a timing at which sufficient ignition energy can be obtained, the first explosion of the engine can be performed appropriately.

  Further, in the above embodiment, the reference timing detection means 12 for detecting the timing at which the primary current of the ignition coil reaches the threshold value as the reference timing is provided in the ignition control unit constituted by the microcomputer, and the reference timing detection means performs the reference. Since the rotational speed information of the engine is obtained from the cycle in which the timing is detected, it is not necessary to separately provide a circuit for generating a signal that gives information on the crank angle of the engine. Therefore, in addition to the ignition circuit 3 constituted by the ignition coil IG and the current control switch 2, a primary current detection unit 6, a microcomputer constituting the ignition control unit, and a power supply circuit for supplying a power supply voltage to the microcomputer Thus, the ignition device can be configured simply by providing the number 5, and the configuration of the current interrupting ignition device can be remarkably simplified.

[Second Embodiment]
FIG. 4 shows the configuration of the second embodiment of the present invention. In the present embodiment, the ignition coil IG includes an additional coil Wa that is connected in series to the primary coil Wp and induces a voltage in phase with the voltage induced in the primary coil. Is induced in the power supply circuit 5. The power supply circuit 5 includes a voltage induced in the additional coil Wa when the first half-wave voltage V1 is induced in the primary coil Wp and an additional coil Wa when the third half-wave voltage V3 is induced in the primary coil Wp. It is configured to convert a voltage induced in DC into a DC voltage.

  In the present embodiment, as shown in FIG. 5, the connection point between the primary coil Wp and the additional coil Wa is grounded to the iron core of the stator of the magnet generator, and the terminal on the non-ground side of the additional coil Wa is the power circuit. 5 is connected to the input terminal on the non-ground side. The power supply circuit 5 shown in FIG. 5 includes a diode D1 having an anode connected to the non-ground side terminal of the additional coil Wa, a capacitor C2 connected between the cathode of the diode D1 and the ground, and both ends of the capacitor C2. The zener diode Zd is connected with the anode facing the ground side, and the voltage across the capacitor C2 is applied to the power supply terminal of the microcomputer MCU as the power supply voltage Vcc. Other configurations of the ignition device according to the second embodiment are the same as the configurations of the ignition device according to the first embodiment shown in FIGS. 1 and 2, and the algorithm of the program executed by the microcomputer MCU is as follows. This is the same as that shown in FIGS.

  As in this embodiment, an additional coil Wa that is connected in series with the primary coil Wp and induces a voltage in phase with the voltage induced in the primary coil Wp is provided on the primary side of the ignition coil. When the power supply circuit 5 is configured to convert the voltage induced in the additional coil Wa when the first half-wave voltage and the third half-wave voltage are induced, the voltage is inverted to the power supply circuit 5. Since it is not necessary to provide a circuit, the configuration of the power supply circuit can be simplified, and the printed circuit board on which the electronic components constituting the power supply circuit 5 and the ignition control unit 10 are mounted can be reduced in size.

[Third Embodiment]
Referring to FIG. 6, the configuration of the third embodiment of the present invention is shown. In addition, FIG. 11 shows waveforms of voltages and currents of respective parts of this embodiment. In the present embodiment, the reference timing detection means 12 provided in the embodiment shown in FIGS. 1 and 4 is omitted, and instead, the voltage induced in the primary coil Wp of the ignition coil IG is waveform-shaped to perform internal combustion. A crank signal generator 7 is provided for generating a crank signal including the crank angle information of the engine. The crank signal generated by the crank signal generator is generated when the first half-wave voltage V1 of the AC voltage VL induced in the primary coil is generated, and when the first half-wave voltage V1 becomes zero (second The timing at which the half-wave voltage is generated), the timing at which the third half-wave voltage V3 is generated (the timing at which the second half-wave voltage V2 is zero), and the third half-wave voltage V3 is zero. It is a rectangular wave signal indicating a level change that can be identified by timing, and the timing indicating each level change is a signal corresponding to a specific crank angle position of the crankshaft. Therefore, information on the rotational angle position of the crankshaft can be obtained from the crank signal, and a level change that occurs at a timing at which a specific level change of the crank signal is detected (for example, the timing at which the first half-wave voltage V1 is generated) The engine speed information can be obtained from the period in which the engine is detected.

  In this case, the microcomputer MCU configures the ignition control unit 10 by using the primary current information detected by the primary current detection unit 6 and the crank angle information given by the crank signal generated by the crank signal generation unit 7. To perform the necessary processing.

  The hardware configuration of the ignition device according to the present embodiment is as shown in FIG. In the ignition device shown in FIG. 7, the configurations of the current control switch 2, the primary current detector 6, the power supply circuit 5, and the microcomputer MCU are the same as the configurations of the power supply circuit 5 shown in FIG.

  The crack signal generator 7 shown in FIG. 7 includes an NPN transistor Tr whose emitter is grounded and a collector connected to the interrupt input terminal INT of the microcomputer, and a non-ground terminal (power circuit) of the capacitor C2 of the power circuit 5. A resistor R5 connected between the collector terminal of the transistor Tr and the resistor R6 connected between the non-grounded terminal of the capacitor C2 of the power supply circuit 5 and the base of the transistor Tr; Between the base of the transistor Tr and the ground, a diode D5 whose anode is connected to the ground side, a diode D6 whose cathode is connected to the non-ground end of the primary coil Wp of the ignition coil, and the base of the transistor Tr One end of the resistor R7 is connected to the anode of the diode D6, and the other end is connected to both ends of the resistor R7. It is constituted by a capacitor C7. A differential circuit is configured by the resistor R7 and the capacitor C7.

  In the crank signal generation unit 7 of FIG. 7, after starting the engine starting operation, when the first half-wave voltage is induced in the primary coil of the ignition coil and the output voltage of the power supply circuit 5 is established, A predetermined base current is applied from the power supply circuit 5 to the transistor Tr through the resistor R6, and a collector voltage is applied from the power supply circuit 5 to the transistor Tr through the resistor R5, so that the transistor Tr is turned on. After the output voltage of the power supply circuit is established, the transistor Tr is kept on even when no voltage is induced in the primary coil. Further, when the primary coil Wp of the ignition coil IG generates the negative first half-wave voltage V1 and the third half-wave voltage V3, the primary coil Wp → the diode D5 → the resistor R7 and the capacitor C7. A current flows through the path of the differentiation circuit → diode D6 → primary coil W1, and a forward voltage drop occurs across the diode D5. This reduces the voltage between the base and the emitter of the transistor Tr, so that the transistor Tr is kept off. It is.

  Therefore, the crank signal input from the crank signal generator 7 shown in FIG. 7 to the interrupt terminal INT of the microcomputer has a waveform as shown in FIG. 11D, and when the engine is started, the output voltage of the power supply circuit is Timing t1 ′ at which the threshold is reached and timing t3 at which the third half-wave voltage V3 is generated rise from a low level to a high level, and the first half-wave voltage V1 becomes zero (second half-wave voltage). At a timing t4 when the second half-wave voltage V3 becomes zero, and a rectangular wave signal that falls from a high level to a low level. In the state where the output voltage of the power supply circuit is maintained at the threshold value or higher, the low level is changed to the high level at the timing t1 when the first half-wave voltage V1 is generated and the timing t3 when the third half-wave voltage V3 is generated. At a timing t2 when the first half-wave voltage V1 becomes zero and a timing t4 when the third half-wave voltage V3 becomes zero, the signal becomes a rectangular wave signal that falls from a high level to a low level.

  When the crank signal having the waveform as described above is generated, the low-level to high level generated at the timing t1 when the first half-wave voltage V1 is generated (timing t1 ′ when the output voltage of the power supply circuit reaches the threshold when the engine is started). Causing the microcomputer to recognize the rise to the level and the fall from the high level to the low level that occurs at the timing t2 when the first half-wave voltage V1 becomes zero and the second half-wave voltage V2 is generated. Thus, the crank angle position information of the engine corresponding to the timings t1 and t2 can be given to the microcomputer, and the period in which the level change of the crank signal generated at the timing t1 is detected (the time required for one rotation of the crankshaft). ) To determine the engine speed. Similarly, the rotational speed of the engine can be obtained from the cycle in which the level change of the crank signal that occurs at timing t2 is detected.

  It should be noted that the level of the crank signal also changes at the timing t3 when the third half-wave voltage V3 is generated (timing when the second half-wave voltage V2 becomes zero) t3 and the timing t4 when the third half-wave voltage V3 becomes zero. However, when the ignition coil primary current is cut off and the ignition operation is performed, the voltage waveform at both ends of the primary coil is greatly disturbed around the timing t3 and t4, and accordingly, the waveform of the crank signal is also disturbed. It is difficult to accurately obtain engine rotation information from changes in the level of the crank signal at timings t3 and t4.

  In this embodiment, the main routine of the program executed by the microcomputer MCU is the same as that shown in FIG. 12, and the memory initialization process is the same as that shown in FIG. The start A / D process is the same as that shown in FIG. 14, and the ignition timer interrupt process is the same as that shown in FIG. In this embodiment, instead of the reference timing interrupt process of FIG. 15 executed by the microcomputer in the first embodiment, an INT input interrupt process shown in FIG. 18 is executed. Since the process for turning on the IGBT T1 is performed in the process of FIG. 18, the timer interrupt process shown in FIG. 16 is not executed.

  The INT input interruption process shown in FIG. 18 is performed from the crank signal generator 7 to the microcomputer at the timing t1 (timing t1 ′ at which the output voltage of the power supply circuit reaches the threshold when the engine is started) shown in FIG. This is executed when a level change from a low level to a high level is applied to the INT terminal of the MCU. In this process, the measured value of the timer for timekeeping is read in step S401 ′, and the measured value read this time and the measured value read in step S01 ′ of the interrupt process at the time of INT input performed previously (before one rotation of the crankshaft) Is detected as a cycle time. The engine speed is calculated from this cycle time, and the timer is restarted.

  In step S402 ', a drive signal is supplied from the port A of the microcomputer to the gate of the IGBT T1 so that the IGBT T1 can be turned on, and interrupt processing at the next INT input is permitted. Next, after the ignition timing measurement value is set in the ignition timer in step S403 ′, the calculation start flag is set in step S404 ′, and then the processing executed when the routine proceeds to the interrupt processing at the time of INT input in step S405 ′. Return to.

  In the present embodiment, the start time fire control means 13 and the normal time fire control means 14 are configured by the INT input interrupt process shown in FIG. The other configuration of the present embodiment is the same as that of the first embodiment shown in FIG. 1, and the engine rotation speed is calculated from the crank signal generation interval instead of detecting the engine rotation speed from the reference timing detection period. The operation similar to that of the first embodiment is performed except that the microcomputer starts to measure the ignition timing when the microcomputer recognizes the change in the level of the crank signal generated at the timing t1 when the first half wave is generated. .

  In the above description, the interrupt processing at the time of INT input is executed when the microcomputer recognizes the crank signal level change at the timing t1, but the INT input is executed when the microcomputer recognizes the crank signal level change at the timing t2. It can also be configured to execute hourly interrupt processing. That is, it is also possible to perform a process for turning on the IGBT at timing t2 and a calculation of the rotational speed of the engine and start measuring the ignition timing.

[Fourth Embodiment]
FIG. 8 shows the overall configuration of the fourth embodiment, and FIG. 9 shows the hardware configuration used in the embodiment. In the present embodiment, as in the second embodiment, the ignition coil IG is connected in series to the primary coil Wp, and the additional coil Wa that induces a voltage having the same phase as the voltage induced in the primary coil is used as the primary coil Wa. The power supply circuit 5 induces a voltage induced in the additional coil Wa when the first half-wave voltage V1 is induced in the primary coil Wp and a third half-wave voltage V3 in the primary coil Wp. In this case, the voltage induced in the additional coil Wa is converted into a DC voltage.

  The power supply circuit 5 shown in FIG. 9 is configured similarly to the power supply circuit 5 (see FIG. 5) used in the second embodiment. 9 includes an NPN transistor Tr whose emitter is grounded and whose collector is connected to the interrupt input terminal INT of the microcomputer, and a non-ground side terminal (power source) of the capacitor C2 of the power circuit 5. The resistor R5 connected between the collector of the transistor Tr, the resistor R8 connected between the base emitter of the transistor Tr, and the anode connected to the non-grounded terminal of the additional coil Wa. And a differential circuit composed of a parallel circuit of a resistor R7 and a capacitor C7 connected between the cathode of the diode D6 and the base of the transistor Tr.

  In the crank signal generator 7 shown in FIG. 9, when the first half-wave voltage is induced in the primary coil Wp and when the third half-wave voltage V3 is induced in the primary coil Wp, the additional coil Since the base current flows from Wa to the transistor Tr through the diode D6 and the differential circuit composed of the resistor R7 and the capacitor C7, the transistor Tr is turned on. When no voltage is induced in the primary coil Wp and when the second half-wave voltage V2 is induced in the primary coil Wp, the transistor Tr is turned off.

  Therefore, the crank signal input from the crank signal generation unit 7 shown in FIG. 9 to the interrupt terminal INT of the microcomputer is the timing t1 (when the first half-wave voltage V1 of the AC voltage VL induced in the primary coil is generated. High level at the timing t3 ′ when the output voltage of the power supply circuit 5 reaches the threshold when the engine is started and the timing when the third half-wave voltage V3 is generated (the timing when the second half-wave voltage V2 becomes zero) t3. At a timing when the first half-wave voltage V1 falls to zero (timing when the second half-wave voltage is generated) t2 and at a timing t4 when the third half-wave voltage V3 becomes zero. It becomes a rectangular wave signal that rises from a low level to a high level. The waveform of the crank signal is a waveform obtained by inverting the waveform of the crank signal shown in FIG.

  In the case of the present embodiment, a level change from a high level to a low level of the crank signal generated at timing t1 (or t1 ′) or a level change from a low level to a high level of the crank signal generated at timing t2 is transmitted to the microcomputer. By making it recognize and performing the interruption process at the time of INT input shown in FIG. 18, the starting time fire control means and the normal time fire control means 14 can be configured.

  10 and 11, the waveforms of the magnetic flux φ interlinked with the primary coil, the voltage VL induced in the primary coil, and the primary current I1 are schematically illustrated by approximating them with triangular waveforms. The actual waveform of the magnetic flux φ interlinked with the voltage VL, the voltage VL induced in the primary coil, and the primary current I1 is a waveform close to a sine wave.

  In each of the above embodiments, the starting point fire control means is configured to obtain the timing at which the primary current detected by the primary current detecting unit reaches the peak value as the starting point fire timing. Alternatively, the starting point fire control means may be configured to obtain the timing when the primary current drops to a set level after passing the peak value as the starting point fire timing.

  In the current interruption type internal combustion engine ignition device, if an excessive voltage is induced in the primary coil when the primary current of the ignition coil is interrupted, the high voltage induced in the secondary coil of the ignition coil becomes too high, and the ignition coil There is a risk that the insulation on the secondary side will be destroyed. In order to prevent such a situation from occurring, it is preferable to provide primary induced voltage limiting means for limiting the voltage induced in the primary coil when the current control switch 2 is cut off to a set level or less.

  The primary induced voltage limiting means is configured such that, for example, a voltage induced in the primary coil Wp when the IGBT is turned off by connecting a Zener diode with the cathode facing the collector side of the IGBT between the collector and gate of the IGBT. It may be realized by configuring a circuit that keeps the IGBT in an on state until it falls below the set level. The semiconductor switch that constitutes the current control switch 2 has an active clamp characteristic (the voltage at both ends is constant) It may be realized by using an IGBT having a function limited to the following, a bipolar transistor, or the like.

DESCRIPTION OF SYMBOLS 1 Magnet generator 2 Current control switch 3 Ignition circuit 4 Spark plug 5 Power supply circuit 6 Primary current detection part 7 Crank signal generation part 10 Ignition control part 11 Switch drive means 12 Reference timing detection means 13 Start time fire control means 14 Normal time Fire control means 14A Rotational speed calculation means 14B Normal time fire timing calculation means 14C Normal time fire timing detection means 14D Switch-off means

Claims (10)

A stator of a magnet generator attached to an internal combustion engine is provided with a primary coil and a secondary coil, and a negative first half wave, a positive second half wave, and a negative third half wave. Are connected in parallel to the ignition coil that induces an AC voltage having a waveform that sequentially appears in the primary coil once during the rotation of the crankshaft of the internal combustion engine, and the primary coil of the ignition coil . A current control switch that is turned on when a half-wave voltage is induced, and when the current control switch is turned from the on state to the off state, the secondary coil of the ignition coil is An internal combustion engine comprising: an ignition circuit that induces a voltage to perform an ignition operation; and an ignition control unit that controls on / off of the current control switch to control a timing (ignition timing) at which the ignition circuit performs an ignition operation With ignition device I,
A primary current detector that detects a primary current flowing through the primary coil of the ignition coil, and a micro that performs processing necessary to configure the ignition controller using information on the primary current detected by the primary current detector A computer, and a power supply circuit that converts an alternating voltage output from the magnet generator into a direct current voltage and supplies the direct current voltage to the microcomputer as a power supply voltage,
The ignition control unit is a switch that provides a drive signal to the current control switch until the second half-wave voltage is induced in the primary coil so that the current control switch can be turned on. Drive means, reference timing detection means for detecting the timing at which the primary current detected by the primary current detection section reaches a threshold as a reference timing, and the primary current detected by the primary current detection section when the internal combustion engine is started. The timing that can be used as the ignition timing at the start of the internal combustion engine is determined from the waveform as the start timing fire timing, and immediately after the start timing fire timing is determined, the current control switch is turned off and the ignition circuit is ignited. A starting point fire control means to be performed, and the internal combustion engine obtained from a cycle in which the reference timing is detected after the start of the internal combustion engine is completed. A normal time point at which the ignition circuit performs an ignition operation by calculating the ignition timing of the internal combustion engine with respect to the rotational speed information of the engine and turning off the current control switch when the calculated ignition timing is detected An ignition device for an internal combustion engine, comprising: a fire control means. A stator of a magnet generator attached to an internal combustion engine is provided with a primary coil and a secondary coil, and a negative first half wave, a positive second half wave, and a negative third half wave. Are connected in parallel to the ignition coil that induces an AC voltage having a waveform that sequentially appears in the primary coil once during the rotation of the crankshaft of the internal combustion engine, and the primary coil of the ignition coil . A current control switch that is turned on when a half-wave voltage is induced, and when the current control switch is turned from the on state to the off state, the secondary coil of the ignition coil is An internal combustion engine comprising: an ignition circuit that induces a voltage to perform an ignition operation; and an ignition control unit that controls on / off of the current control switch to control a timing (ignition timing) at which the ignition circuit performs an ignition operation With ignition device I,
A primary current detector that detects a primary current flowing through the primary coil of the ignition coil; a crank signal generator that generates a crank signal including crank angle information of the internal combustion engine using a voltage induced in the primary coil; A microcomputer that performs processing necessary to configure the ignition control unit using information on the primary current detected by the primary current detection unit and crank angle information given by the crank signal, and an output from the magnet generator A power supply circuit that converts an alternating current voltage into a direct current voltage and applies the direct current voltage to the microcomputer as a power supply voltage,
The ignition control unit is a switch that provides a drive signal to the current control switch until the second half-wave voltage is induced in the primary coil so that the current control switch can be turned on. A timing that can be used as an ignition timing at the start of the internal combustion engine is determined as a start timing fire timing from a waveform of a primary current detected by the drive means and the primary current detection unit at the start of the internal combustion engine. And a starting point fire control means that immediately turns off the current control switch to perform an ignition operation in the ignition circuit, and obtained from the crank signal generation interval after the start of the internal combustion engine is completed. The ignition timing of the internal combustion engine is calculated with respect to the rotational speed information of the internal combustion engine, and the current control switch is turned off when the calculated ignition timing is detected. Ignition device for an internal combustion engine, characterized by comprising a normal ignition control means for causing an ignition operation in the ignition circuit by.   The power supply circuit is configured to convert a first half-wave voltage and a third half-wave voltage induced by the primary coil into a DC voltage and to supply the DC voltage to the microcomputer as a power supply voltage. The internal combustion engine ignition device according to claim 1 or 2. The ignition coil includes, on the primary side, an additional coil that is connected in series to the primary coil and induces a voltage having the same phase as the voltage induced in the primary coil.
The power supply circuit induces a voltage induced in the additional coil when a first half-wave voltage is induced in the primary coil and a voltage induced in the additional coil when a third half-wave voltage is induced in the primary coil. The ignition device for an internal combustion engine according to claim 1 or 2, wherein a voltage to be converted is converted into the DC voltage.   The start time fire control means is configured to obtain a timing at which the primary current detected by the primary current detector reaches a peak value as the start time fire timing. The ignition device for internal combustion engines as described.   The starting point fire control means is configured to obtain a timing when the primary current detected by the primary current detecting unit drops to a set level after passing a peak value as the starting point fire timing. The internal combustion engine ignition device according to claim 1 or 2.   The ignition control unit controls the ignition timing by the start point fire control means until the number of ignition operations performed after starting the start operation of the internal combustion engine reaches a set number of times. The ignition timing is controlled by the normal time point fire control means after the number of ignition operations performed after starting the starting operation reaches a set number. 2. An ignition device for an internal combustion engine according to 2.   The crank signal generation unit receives an AC voltage induced in the primary coil of the ignition coil as input, and the timing at which the first half wave of the waveform of the AC voltage starts or the waveform of the AC voltage starts from the first half wave. The ignition device for an internal combustion engine according to claim 2, wherein the crank signal is generated at a timing of shifting to the second half wave. The ignition coil includes, on the primary side, an additional coil that is connected in series to the primary coil and induces a voltage having the same phase as the voltage induced in the primary coil.
The crank signal generation unit receives the voltage induced in the additional coil as input, and the timing at which the first half wave of the waveform of the alternating voltage induced in the primary coil starts or the waveform of the alternating voltage induced in the primary coil 3. The internal combustion engine ignition device according to claim 2, wherein the crank signal is generated at a timing of transition from the first half wave to the second half wave. 4.   3. The internal combustion engine according to claim 1, further comprising primary induced voltage limiting means for limiting a voltage induced in the primary coil to a set level or less when the current control switch is cut off. Engine ignition device.

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