JP2007198190A - Non-contact ignition device of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stably control the operation of an internal combustion engine at an arbitrarily set ignition timing with good control response and without being affected by the mounting accuracy between a rotor and a core. <P>SOLUTION: During the starting of the internal combustion engine, a switching element 12 is driven by a control pulse provided by the negative induced voltage of a trigger coil 1 for each rotation of the internal combustion engine. After the internal combustion engine is started, the switching element 12 is driven by a control pulse provided by two positive induced voltages of the trigger coil 1 for each rotation of the internal combustion engine. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a non-contact ignition device for an internal combustion engine of a capacitor charge / discharge type that makes it possible to adjust the ignition timing of the internal combustion engine.

  As a conventional non-contact ignition device for an internal combustion engine, for example, when a rotor having a magnetic pole rotates, a voltage induced by an exciter coil is charged into a charge / discharge capacitor for ignition, and the charge charged in the charge / discharge capacitor is converted into a trigger coil. Some of them are supplied to the ignition coil through a switching element that is switched by a voltage induced by.

  In this contactless ignition device for an internal combustion engine, when the rotational speed of the internal combustion engine, that is, the rotational speed of the rotor is increased, the charging / discharging timing of the charging / discharging capacitor for ignition is accelerated, and finally the rotational speed of the internal combustion engine is increased. There is a case where the engine speed increases beyond the set rotational speed and the internal combustion engine is seized.

  On the other hand, by using a plurality of switching elements and impedance elements that monitor the rotational speed of the internal combustion engine, when the internal combustion engine reaches a set rotational speed, the ignition timing of the ignition charge / discharge capacitor is delayed. There is provided a non-contact ignition device for an internal combustion engine that can prevent over-rotation of the internal combustion engine by electrical control.

  However, the conventional contactless ignition device for an internal combustion engine based on such electrical control uses two or more switching elements and impedance elements, so that it occupies a large space for mounting and has a circuit configuration. It becomes complicated and the cost of the whole apparatus becomes high.

  On the other hand, by adding a time constant circuit for setting the charging / discharging timing of the ignition charging / discharging capacitor to the non-contact ignition device of the internal combustion engine, it is possible to reduce the cost of the internal combustion engine at low cost without complicating the circuit configuration. A non-contact ignition device for an internal combustion engine that prevents rotation is provided.

  In this non-contact ignition device for an internal combustion engine, a rotor having a magnetic pole disposed with a magnet interposed therebetween, a core disposed opposite to the rotor and wound with an exciter coil and a trigger coil, and a positive induced voltage of the exciter coil And an ignition charge / discharge capacitor for charging the ignition coil, and when the positive induced voltage of the trigger coil reaches a predetermined trigger level, the switching element is triggered to supply the charge of the charge / discharge capacitor for ignition to the ignition coil. (For example, refer to Patent Document 1).

Therefore, in this non-contact ignition device for an internal combustion engine, for example, a charge / discharge circuit for charging the positive induced voltage of the trigger coil is provided, and when the internal combustion engine exceeds the set rotational speed, the discharge time constant of the charge / discharge circuit The charging / discharging capacitor for ignition can be prohibited by turning on the switching element based on the switching element. Therefore, the internal combustion engine is in a misfire state, and an increase in the rotational speed (overspeed) of the internal combustion engine can be suppressed.
JP 2001-193618 A

  However, in such a conventional contactless ignition device for an internal combustion engine, the switching element is driven and controlled using an induced voltage of a trigger coil that changes in an analog manner, and therefore the ignition timing of the internal combustion engine is advanced. There was an inconvenience that each control response of the advance angle, retard angle and misfire was delayed.

  In addition, there is a problem in that the ignition timing and misfire timing to be controlled vary due to variations in mounting (mainly gap) accuracy between a rotor having a magnet or magnetic pole and a core having an exciter coil or trigger coil.

  The present invention solves such a conventional problem, and the control response is good by the digital processing of the control pulse obtained from the induced voltage of the trigger coil, and the setting is made without being affected by the mounting accuracy between the rotor and the core. It is an object of the present invention to provide a contactless ignition device for an internal combustion engine capable of stably controlling the operation of the internal combustion engine at the ignition timing.

  To achieve the above object, a contactless ignition device for an internal combustion engine according to the present invention is obtained based on a negative induced voltage of the trigger coil for each rotation of the internal combustion engine at the start of start of the internal combustion engine. The switching element is driven by a control pulse, and after the internal combustion engine is started, the switching element is driven by one control pulse obtained based on two positive induced voltages of the trigger coil every rotation of the internal combustion engine. Control means is provided.

  With this configuration, the internal combustion engine can be started quickly using the control pulse obtained from the negative induced voltage of the trigger coil, and the control pulse obtained from the positive induced voltage of the trigger coil is used after activation. Thus, the operation of the internal combustion engine can be promptly shifted to the arbitrarily set rotation speed and ignition timing state.

  Further, the non-contact ignition device for an internal combustion engine according to the present invention is configured such that the control means has the digital control pulse obtained based on the induced voltage with respect to the generation timing of the pulse signal based on the two positive induced voltages. Is a microcomputer that controls the ignition timing of the internal combustion engine to be advanced or delayed.

  With this configuration, it is possible to optimally perform advance control, retard control and misfire control of ignition timing according to the internal combustion engine speed according to a program prepared in advance by digital processing. Further, the ignition timing and the misfire rotation speed can be set with high accuracy and speed without being affected by the structural variation in the gap between the core and the rotor.

  Further, in the non-contact ignition device for an internal combustion engine according to the present invention, the control means monitors the internal combustion engine speed based on the generation timing of the two positive induced voltages, and the misfire rotational speed set by the internal combustion engine by a program. In this case, the switching element is driven to stop charging the ignition charge / discharge capacitor.

  With this configuration, the rotational speed of the internal combustion engine can be rapidly controlled to a predetermined rotational speed at a preset ignition timing.

  The present invention has a control means, which is based on the negative induced voltage of the trigger coil when starting the internal combustion engine, and that the trigger coil is positively induced after starting the internal combustion engine. By generating a control pulse for ignition control of the internal combustion engine from each pulse signal obtained based on the voltage and driving the switching element by this control pulse, the internal combustion engine can be started quickly, and the internal combustion engine After starting, the operation of the internal combustion engine can be promptly shifted to an arbitrarily set rotational speed and ignition timing state.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a partially cutaway front view of a main part configuration of a contactless ignition device for an internal combustion engine according to an embodiment of the present invention. FIG. 2 shows a contactless ignition device for an internal combustion engine according to an embodiment of the present invention. It is a circuit diagram.

  In FIG. 1, a trigger coil 1 and an exciter coil 2 constituting a contactless ignition device are wound around both leg portions 8 a and 8 b of a U-shaped core 8. Here, the exciter coil 2 is wound around a leg portion 8b on the rotation direction 4 side of the rotor 3, which will be described later, and the trigger coil 1 is wound around a leg portion 8a on the opposite side to the rotation direction.

  Further, the rotor 3 is arranged at a position facing the core 8 so as to be capable of high-speed rotation. The rotor 3 is made of a non-magnetic columnar block such as aluminum, and a pair of magnetic poles 6 and 7 are embedded in the columnar block with a magnet 5 interposed therebetween.

  A part of the magnetic poles 6 and 7 is exposed on the outer periphery of the rotor 3, and can pass through the end surfaces of both the leg portions 8 a and 8 b of the core 8 while the rotor 3 is rotating. Further, the end surfaces of both the leg portions 8 a and 8 b of the core 8 are formed in an arc shape so that a gap (distance) having a constant width can be held with respect to the outer peripheral surface of the rotor 3.

  In addition, the size and installation interval of the magnetic poles 6 and 7 and the size and interval of both the leg portions 8a and 8b of the core 8 are set according to the charge / discharge timing and trigger timing of the charge / discharge capacitor described later.

  FIG. 2 is a circuit diagram showing a contactless ignition device for the internal combustion engine. In the figure, a diode 9, an ignition charging / discharging capacitor 10 and a primary coil 11a of an ignition coil 11 are connected in series to the exciter coil 2, and these generate a positive voltage induced by the exciter coil 2 in the ignition charging / discharging capacitor 10 Constitutes a charging circuit for charging.

  The ignition charge / discharge capacitor 10 is connected in series with the anode / cathode of the thyristor 12 as a switching element and the primary coil 11a of the ignition coil 11. The thyristor 12 and the ignition coil 11 constitute a discharge circuit that discharges the charge of the ignition charge / discharge capacitor 10 to the primary coil 11 a of the ignition coil 11.

  According to this, when the thyristor 12 is triggered and becomes conductive, the charge of the ignition charge / discharge capacitor 10 is discharged to the ignition coil 11. The thyristor 12 also functions to prevent charging of the ignition charge / discharge capacitor 11 by shunting the exciter coil 2 by a trigger.

  Further, a spark plug 13 is connected to the secondary coil 11 b of the ignition coil 11. Further, between the anode and the cathode of the thyristor 12, a backflow preventing diode 14 that also serves to charge the charge / discharge capacitor 10 is connected.

  On the other hand, both terminals of the trigger coil 1 are connected to a microcomputer 15 as control means for outputting a control pulse. The output terminal of the microcomputer 15 is connected to the gate of the thyristor 12 for inputting the control pulse.

  The microcomputer 15 shapes the voltage induced by the trigger coil 1, converts it to digital, performs signal waveform processing according to a predetermined program, and inputs the obtained control pulse to the gate of the thyristor 12. To work.

  Therefore, when starting the internal combustion engine, the microcomputer 15 drives the thyristor 12 with one control pulse obtained based on the negative induced voltage of the trigger coil 1 for each rotation of the internal combustion engine. After starting, the thyristor 12 is driven by one control pulse obtained based on two positive induced voltages of the trigger coil 1 for each rotation of the internal combustion engine.

  Next, the operation of the contactless ignition device for the internal combustion engine will be described with reference to the timing chart of each part of the circuit shown in FIG. First, when the internal combustion engine is operated and the rotor 3 rotates in the direction of the arrow 4 in FIG. 1, the trigger coil 1 and the exciter coil 2 on the core 8 facing the rotor 3 are provided with FIGS. Each voltage of the waveform shown in FIG.

  Of the induced voltage of the exciter coil 2, a positive voltage is applied to the charge / discharge capacitor 10 for ignition via the diode 9 and the primary coil 11 a of the ignition coil 11, and the charge / discharge capacitor 10 for charge is charged. Is charged. As shown in FIG. 3F, this charged charge is held until a discharge timing described later.

  On the other hand, the induced voltage of the trigger coil 1 falls after a predetermined period from the rising of the positive induced voltage of the exciter coil 2 and is input to the microcomputer 15.

  The microcomputer 15 shapes the induced voltage of the trigger coil 1 and generates two positive input pulses p1 and p2 as shown in FIG. 3B from positive and negative voltages exceeding the set level, and FIG. Each positive input pulse p3 as shown in c) is extracted and recognized.

  Here, FIG. 3B is the positive pulses p1 and p2 obtained based on the positive input voltage of FIG. 3A, and FIG. 3C is the negative pulse of FIG. This is a positive pulse p3 obtained based on the input voltage. The pulse p3 is located between the two pulses p1 and p2.

  At the start of the internal combustion engine, the microcomputer 15 uses the pulse p5 shown in FIG. 3 (d), which is generated in synchronization with the recognized pulse p3 shown in FIG. 3 (c), as a control pulse. Input to the gate of the thyristor 12. The control pulse p5 is used for discharging the charge of the charge / discharge capacitor 10 at the next rotation cycle of the internal combustion engine.

  Therefore, when the thyristor 12 is triggered by the output of the control pulse p5, the charge charged in the charge / discharge capacitor 10 one cycle before is discharged to the primary coil 11a of the ignition coil 11 through the anode and cathode of the thyristor 12. Is done. For this reason, a high voltage is instantaneously applied to the secondary coil 11b, a spark is generated in the spark plug 13, and the air-fuel mixture in the internal combustion engine is ignited.

  The ignition of the air-fuel mixture by the control pulse p5 at the time of starting the internal combustion engine is performed for, for example, about 2 to 6 revolutions at the time of starting the internal combustion engine. As a result, the rotation of the internal combustion engine rises smoothly and gradually increases to the rotation speed of the normal operation mode (main mode).

  On the other hand, when the internal combustion engine is started and the rotational speed gradually increases, the microcomputer 15 generates the control pulse p4 shown in FIG. 3 (e) based on the recognized pulse p1 shown in FIG. 3 (b). The control pulse p4 is input to the gate of the thyristor 12. The microcomputer 15 stops the output of the control pulse p5 in FIG. 3 (d) at the timing when the internal combustion engine has rotated 2-6 times at the start, and based on the pulse p1 from the seventh rotation of the internal combustion engine. The control pulse p4 generated in this way is output.

  The control pulse p4 is output by signal processing by the microcomputer 15 so as to be located within a time t1 from the rising timing of the pulse p1 to the rising timing of the pulse p2.

  The time t1 from the rising timing of the pulse p1 to the rising timing of the pulse p2 is information on the rotational speed (rotational speed) of the internal combustion engine, and the position (time t2) of the control pulse p4 within the time t1 is also the internal combustion engine. Information on the engine speed.

  The control pulse p4 is input to the gate of the thyristor 12 to trigger it, and becomes a control signal for determining the discharge timing of the charge / discharge capacitor 10, that is, the ignition timing of the internal combustion engine. Therefore, this control signal becomes information for determining the rotational speed of the internal combustion engine.

  By moving the control pulse p4 in the advance direction <arrow S direction> or the retard direction (arrow R direction) by digital processing by the microcomputer 15 with respect to the pulse p1, the ignition timing of the internal combustion engine is set to the user. Can be freely set according to the characteristics of the internal combustion engine.

  The microcomputer 15 grasps the current internal combustion engine speed by measuring the time t1, and arbitrarily sets the time t2 based on the first pulse p1 waveform obtained from the trigger coil 1 after one cycle. Thus, the charge of the charge / discharge capacitor 10 is discharged as shown in FIG.

  Thereby, the ignition timing of the internal combustion engine is controlled. This time t2 (ignition timing) can be arbitrarily set for each engine speed by digital signal processing by a program.

  Therefore, when the computer 15 switches the position of the control pulse p4 by a program and the speed of the internal combustion engine rises sufficiently and then recognizes a deceleration operation, the speed of the internal combustion engine is preset according to the program. It can be held stably at idling speed. In addition, after that, it is possible to quickly start up to the target rotational speed in a timely manner according to the program.

  In this way, the rotational speed of the internal combustion engine can be set and changed by setting the time t2 in advance fixedly or arbitrarily on the program. As a result, the supply timing of the ignition voltage to the spark plug can be adjusted, and for example, over-rotation prevention of the internal combustion engine and rapid response control of the internal combustion engine rotation from the high speed region to the idling region can be easily performed.

  Further, since the rotational speed of the internal combustion engine can be confirmed at time t1 in FIG. 3B, the rotational speed of the internal combustion engine to be misfired can be set in advance by a program. Thus, when the internal combustion engine speed to be misfired is reached, the control pulse p4 as shown in FIG. 3 (e) is promptly input to the gate of the thyristor 12, thereby supplying the charge / discharge capacitor 10 to the charge / discharge capacitor 10. Charging can be prevented and misfire can be realized easily and reliably.

  In this case, it is possible to restart the internal combustion engine by restarting the ignition after the misfire by setting the return rotation speed from the misfire.

  As described above, in the digital control using the microcomputer, the advance control and retard control of the ignition timing of the internal combustion engine can be easily performed by setting the program, and the ignition is controlled by the variation in the gap between the core 8 and the rotor 3. It is possible to prevent the timing and misfire rotation speed from varying.

  Further, since the conventional core 8, rotor 3, exciter coil 2 and trigger coil 1 can be used as they are or only by changing the number of turns of each coil 1 and 2, a conventional cup case (which can be stored together with the microcomputer 15) (Not shown) can be easily attached to the internal combustion engine.

  As described above, according to the present embodiment, the control means such as the microcomputer 15 is provided, and the control means obtains the control obtained in synchronization with the negative induced voltage of the trigger coil 1 when the internal combustion engine starts. The switching element 12 such as the thyristor 12 is driven by the pulse p5, and after starting the internal combustion engine, a control pulse p4 for controlling the ignition timing of the internal combustion engine is generated from the pulse signal obtained based on the positive induced voltage of the trigger coil 1 Then, by driving the switching element 12 with this control pulse p4, the digital pulse obtained from the negative induced voltage of the trigger coil 1 can be used to quickly start the internal combustion engine. Using the digital pulse obtained from the positive induced voltage of the trigger coil 1, an arbitrarily set rotation speed and ignition timing It can be quickly migrate operation of the internal combustion engine to the timing condition.

  In addition, since the ignition timing is digitally controlled, it can be set for each rotation speed without being affected by various structural errors of the core 8 and the rotor 3.

  The contactless ignition device for an internal combustion engine of the present invention can obtain a good control response by switching control with a digital control pulse obtained from the induced voltage of the trigger coil, and is not affected by the mounting accuracy between the rotor and the core. The internal combustion engine can be stably controlled at a set ignition timing, and is useful as a non-contact ignition device for an internal combustion engine that can control the ignition timing of the internal combustion engine.

1 is a partially cutaway front view of a main part configuration of a contactless ignition device for an internal combustion engine according to an embodiment of the present invention. 1 is a circuit diagram showing a contactless ignition device for an internal combustion engine according to an embodiment of the present invention. 3 is a timing chart showing signal waveforms at various parts of the circuit in FIG. 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Trigger coil 2 Exciter coil 3 Rotor 5 Magnet 6, 7 Magnetic pole 8 Core 10 Charging / discharging capacitor | condenser 11 Ignition coil 12 Thyristor (switching element)
13 Spark plug 15 Microcomputer (control means)

Claims (3)

A rotor having two magnetic poles arranged with a magnet interposed therebetween, a core disposed opposite to the rotor and wound with an exciter coil and a trigger coil, and charging / discharging for ignition charging a positive induced voltage of the exciter coil A non-contact ignition device for an internal combustion engine comprising a capacitor and a switching element that is triggered by an induced voltage of the trigger coil to be conductive and supplies a charge of the ignition charge / discharge capacitor to an ignition coil. At the start of starting, the switching element is driven by one control pulse obtained based on the negative induced voltage of the trigger coil for every rotation of the internal combustion engine. After the internal combustion engine is started, every time the internal combustion engine is rotated A single control pulse obtained based on two positive induced voltages of the trigger coil causes the switching element to Contactless ignition system for an internal combustion engine characterized by comprising a dynamic control unit. The control means controls the control pulse obtained based on the positive induced voltage with respect to the generation timing of the two positive induced voltages in a direction to advance or delay the ignition timing of the internal combustion engine. The contactless ignition device for an internal combustion engine according to claim 1, wherein: The control means monitors the internal combustion engine speed based on the generation timing of the two positive induced voltages, and when the internal combustion engine reaches a misfire speed set by a program, drives the switching element to 2. The non-contact ignition device for an internal combustion engine according to claim 1, wherein charging to the charge / discharge capacitor is stopped.

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