JP4292945B2 - Ignition device for internal combustion engine - Google Patents

Description

  The present invention relates to an ignition device for an internal combustion engine provided with a safety circuit that prevents the start of the engine when a condition for prohibiting the start of the internal combustion engine is satisfied.

In an internal combustion engine for a vehicle, if the engine is started when the gear position of a transmission provided between the engine output shaft and the load is not in the neutral position, the vehicle suddenly starts and is dangerous. A safety circuit is provided that prevents the engine from starting when the gear position of the transmission is at a position other than the neutral position and the parking position when the engine is started. Also, in motorcycles, it is dangerous to run with the stand upright, so if the start operation is performed with the stand upright, the ignition operation is blocked and engine start is prohibited. A circuit is provided. A conventional internal combustion engine ignition device including a safety circuit is disclosed in Patent Document 1, for example.
Japanese Patent Laid-Open No. 10-47218

  As a method for starting an internal combustion engine, there are a method using a starter operated by human power such as a recoil starter or a kick starter, and a method using a starter motor. When the engine is operating, the ignition operation is not performed even if the engine is started, and the engine cannot be started. Therefore, when the driver is not aware that the safety circuit is working when the engine is started, the engine starting operation is repeated many times.

  When a starter by human power is used, even if the start operation is repeated, it is only necessary that the engine does not start. However, when a starter motor is used, if the start operation is repeated many times, the battery will run out. Since a state arises, it is not preferable.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an internal combustion engine ignition device that prevents a starter motor from performing a start operation when a safety circuit is in operation and prevents a battery from being consumed. is there.

  The present invention includes an ignition coil and a primary current control circuit that controls a primary current of the ignition coil, and an ignition circuit that induces a high voltage for ignition in a secondary coil of the ignition coil at an ignition timing of the internal combustion engine; A safety switch that is maintained in an on state when a condition that allows the start of the internal combustion engine is satisfied, and that is maintained in an off state when a condition that prohibits the start of the internal combustion engine is satisfied; The ignition circuit is allowed to generate a high ignition voltage when the safety switch is on during start-up, and the ignition circuit is high when the safety switch is off during start-up of the internal combustion engine. The present invention relates to an internal combustion engine ignition device including a safety circuit that prevents the occurrence of

  In the present invention, a relay having a normally open contact is provided, and an exciting coil of the relay is connected to both ends of the battery through an engine start switch that is closed during engine start operation and the safety switch. A starter motor that is driven when starting the engine is connected to both ends of the battery through the normally open contact of the relay and the engine starting switch.

  In the above ignition device, when the engine start condition is satisfied and the engine start switch is closed while the safety switch is closed, the relay excitation coil is energized. Is closed, the starter motor is energized, and the engine is cranked. At this time, since the ignition circuit generates a high voltage for ignition in the secondary coil of the ignition coil at the ignition timing of the engine, the ignition of the engine is performed without any trouble and the engine is started.

  On the other hand, when the conditions for prohibiting engine start are satisfied and the safety switch is in the OFF state, the relay excitation coil is not excited even when the engine start switch is closed. Is not done. As described above, when the condition for allowing the engine to start is not satisfied, the starter motor is not energized even when the driver closes the start switch and performs the start operation. Therefore, the unnecessary start operation is repeated. Can prevent the battery from draining.

  In an internal combustion engine ignition device, an ignition coil having a primary coil and a secondary coil grounded at one end is provided in a magnet generator driven by the engine, and the primary coil of the ignition coil is synchronized with the rotation of the engine. In many cases, AC voltage is induced. Thus, when providing an ignition coil in a magnet generator, the primary coil of an ignition coil is used as an ignition power supply, and a primary current control circuit is connected to the primary coil of the ignition coil.

  The primary current control circuit includes a primary current control transistor that is turned on when a half-wave voltage of one polarity is induced in the primary coil of the ignition coil and shorts the primary coil, and an internal combustion engine. A transistor control circuit for controlling the primary current control transistor to be in a cutoff state at the ignition timing of the ignition coil, and when the primary current control transistor is in the cutoff state, a high voltage for ignition is applied to the secondary coil of the ignition coil A current interrupting type that induces the current is often used.

  When such a current interrupting type primary current control circuit is used, the safety circuit is charged with the half-wave voltage of the other polarity when a half-wave voltage of the other polarity is induced in the primary coil of the ignition coil. A control power supply circuit that generates a control DC voltage with a power supply capacitor connected to the primary coil, and a trigger signal input terminal is connected to one end of the primary coil through a resistor to induce the primary coil An ignition blocking switch that is in a conductive state while a trigger signal is given by a half-wave voltage of one polarity and the half-wave voltage of one polarity is generated, and a trigger signal input terminal of the ignition blocking switch and a primary An ignition prevention control switch that is connected between the other end of the coil and that conducts when a drive signal is applied and prevents a trigger signal from being applied to the ignition prevention switch; When the anode is connected to the output terminal on the positive polarity side of the control power circuit through a resistor and the cathode is connected to the drive signal input terminal of the ignition prevention control switch, and a gate signal higher than the ON level is given between the anode gates And a drive signal supply PUT for supplying a drive signal from the control power supply circuit to the ignition prevention control switch.

  In this case, one end of the safety switch is grounded through the first diode with the cathode facing the ground side and connected to the output terminal on the negative polarity side of the control power supply circuit through the current limiting element, and the other end of the safety switch is The cathode is preferably connected to a circuit connected to the gate of the drive signal supply PUT through a second diode directed toward the safety switch.

  As described above, according to the present invention, a relay having a normally open contact is provided, and the excitation coil of the relay is connected to both ends of the battery through the engine start switch and the safety switch that are closed during engine start operation. Since the starter motor that is driven when starting the internal combustion engine is connected to both ends of the battery through the normally open contact of the relay, the condition for prohibiting the engine start is satisfied and the safety switch is turned off. It is possible to prevent the starter motor from being energized when the start switch is closed in the state. Accordingly, it is possible to prevent the battery from being exhausted by repeated useless starting operations in a state where the conditions for prohibiting engine start are satisfied and the ignition operation is blocked.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a configuration of an embodiment of the present invention, in which 1 is a current interrupting type ignition circuit, 2 is a safety circuit, and 3 is a safety switch.

  The ignition circuit 1 includes an ignition coil 4, a primary current control transistor 5 that controls a primary current of the ignition coil, and a transistor control circuit 6.

  The ignition coil 4 is provided in a magnet generator in which at least the primary coil 4a is driven by the engine, and an alternating voltage is induced in the primary coil 4a in synchronization with the rotation of the engine. One end of the primary coil 4a and secondary coil 4b of the ignition coil is grounded, and the other end of the secondary coil 4b is connected to a non-ground side terminal of a spark plug 7 attached to a cylinder of an engine (not shown).

  The transistor control circuit 6 turns on the transistor 5 to cause the primary current to flow through the ignition coil when a half-wave voltage of one polarity in the direction of the broken arrow shown in the figure is induced in the primary coil of the ignition coil. When the timing is detected, the transistor 5 is turned off to interrupt the primary current of the ignition coil. By cutting off the primary current, a high voltage for ignition is induced in the secondary coil of the ignition coil, and this high voltage causes a spark discharge in the spark plug 7 to ignite the engine.

  The safety circuit 2 includes an ignition prevention switch 8 made up of a thyristor Th, an ignition prevention control switch 9 made up of an NPN transistor TR, a control power supply circuit 10, an output terminal of the control power supply circuit 10, and driving of the ignition prevention control switch 9 A drive signal supply PUT (programmable uni-junction transistor) 11 connected between the signal input terminals is provided.

  The control power supply circuit 10 includes a power supply capacitor that is charged by the half-wave voltage of the other polarity when a half-wave voltage of the other polarity is induced in the primary coil 4a of the ignition coil, This circuit generates a control DC voltage.

  In the illustrated example, the anode of the diode D1 is connected to the non-ground side terminal of the primary coil 4a of the ignition coil, and the anode of the diode D2 is connected to the cathode of the diode D1. One end of a first power supply capacitor C1 is connected to the cathode of the diode D2, and the other end of the capacitor C1 is grounded through a diode D3 with the anode facing the capacitor.

  One end of the first power supply capacitor C1 is also connected to one end of the second power supply capacitor C2 through a diode D4 with the anode directed to the capacitor side, and the other end of the second power supply capacitor C2 is connected to the cathode of the diode D1. ing. A resistor R1 having a small resistance value is connected between the other end of the second power supply capacitor C2 and the other end of the first power supply capacitor C1, and the diodes D2 and D3, the capacitors C1 and C2, and the resistor R1 A control power supply circuit 10 is configured.

  In this control power supply circuit, the first power supply capacitor C1 is charged to the polarity shown through the diode D2 by the half-wave voltage of the other polarity in the direction of the solid line shown in the figure induced in the primary coil 4a. When the induced voltage of the primary coil 4a passes the peak and the charging of the first power supply capacitor C1 is stopped, the charge accumulated in the first power supply capacitor C1 is discharged through the diode D4, the second power supply capacitor C2, and the resistor R1. Then, the second power supply capacitor C2 is charged to the illustrated polarity. In this power supply circuit, both ends of the second power supply capacitor C2 are output terminals 10a and 10b, and a DC voltage is output between these output terminals.

  The ignition prevention control switch 9 is composed of an NPN transistor TR whose collector and emitter are connected to the gate and cathode of a thyristor Th, respectively, the cathode of a drive signal supply PUT 11 is connected to the base, and the anode of PUT 11 is a resistor It is connected to the output terminal 10a on the positive polarity side of the control power supply circuit 10 through R2.

  The safety switch 3 is a switch that maintains an ON state when a condition that allows the engine to start is satisfied, and maintains an OFF state when a condition that prohibits the engine from starting. The condition for prohibiting the start of the engine is satisfied, for example, when the gear position of the transmission is in a position (position for transmitting power) other than the neutral position and the parking position when the engine is started. In this way, when the engine is prohibited from starting when the gear position of the transmission is at a position other than the neutral position and the parking position, the ON state is set when the gear position of the transmission is at the neutral position and the parking position. A switch that is configured to hold and to maintain an off state when the gear position of the transmission is in a position other than the neutral position and the parking position is used as a safety switch.

  In motorcycles, when starting the engine while the stand is standing up, the off state is maintained when the stand is standing, and the on state is maintained when the stand is not standing. A switch provided in this way is used as a safety switch.

  In addition, when the engine start is prohibited when the engine lubricating oil is insufficient, the engine is kept off when the lubricating oil level is below the specified level, and the lubricating oil level is above the specified level. A switch that maintains the ON state is used as a safety switch.

  One end of the safety switch 3 is grounded through a diode D3 (first diode) whose cathode is directed to the ground side, and is connected to the negative polarity side output terminal of the control power supply circuit 10 through a resistor R1 as a current limiting element. The other end of the switch is connected to a circuit connected to the gate of the drive signal supply PUT through a diode D5 (second diode) with the cathode facing one end of the safety switch.

  A resistor R4 is connected between the gate and anode of the thyristor Th, and a resistor R5 and a diode D6 with the cathode facing the gate side of the thyristor Th are connected in parallel between the gate and cathode of the thyristor Th. A resistor R6 and a capacitor C3 are connected in parallel between the anode gates of the PUT 11.

  In the illustrated safety circuit, when the safety switch 3 is closed, the power source capacitor C2-the resistance R2-PUT11 anode-gate-resistance R3-diode D5-safety switch 3-resistance (current limiting element) R1-the power source capacitor C2 The gate current of PUT 11 flows through the path, and PUT 11 becomes conductive. At this time, the base current of the transistor TR flows through the path of the power supply capacitor C2-resistance R2-PUT11-base / emitter-diode D1-transistor TR2 of the transistor TR. At the same time as the half-wave voltage of one polarity is induced, it is turned on.

  In this way, when the safety switch 3 is closed, the primary coil 4a generates a half-wave voltage of one polarity in the direction of the broken line in the figure, and at the same time, the transistor TR as the ignition prevention control switch is turned on. The trigger signal applied to the thyristor 8 from the primary coil 4a through the resistor R4 is bypassed from the thyristor through the transistor TR. Therefore, when the safety switch 3 is closed, the thyristor Th (ignition prevention switch 8) does not conduct and the primary coil of the ignition coil is not short-circuited, so that the ignition operation is performed without any problem. Once the PUT 11 is turned on, the control power supply circuit 10 maintains the conduction state as long as the voltage is output. Therefore, even if the safety switch is turned off after the engine is started, the ignition operation is not blocked. The engine is operated without any problems.

  On the other hand, when the safety switch 3 is open at the time of starting the engine, the PUT 11 is not conducted and the transistor TR is not conducted. When this occurs, a trigger signal is applied to the thyristor Th through the resistor R4, and the thyristor becomes conductive. Therefore, the primary current of the ignition coil cannot be interrupted, and the ignition operation is blocked. As described above, when the safety switch is open when the engine is started, the ignition operation is not performed even if the start operation is performed, and therefore the engine cannot be started.

  In the present invention, in order to enable the start of the engine by the starter motor, the relay 12 having the normally open contact 12a is provided, and the excitation coil 12Y of this relay is closed only during the start operation of the engine. Through the switch (key switch) 13 and the safety switch 3, the negative electrode is connected to both ends of the grounded battery 14. A starter motor 15 that drives the crankshaft of the engine when the internal combustion engine is started is connected to both ends of the battery 14 through a normally open contact 12 a of the relay 12.

  Thus, the relay 12 having a normally open contact is provided, the exciting coil 12Y of the relay 12 is connected to both ends of the battery 14 through the engine start switch 13 and the safety switch 3, and the starter motor 15 is connected to the normally open relay. If it is configured to connect to both ends of the battery 14 through the contact 12a, the starter 13 is closed when the start switch 13 is closed in a state where the condition for prohibiting the engine start is satisfied and the safety switch is in the OFF state. Since it is possible to prevent the motor from being energized, the condition for prohibiting engine start is established, and unnecessary start operations are repeated in a state where the ignition operation is blocked, and the battery 14 is consumed. Can be prevented.

  In the above embodiment, the current interruption type ignition circuit is used, but the present invention can also be applied when a capacitor discharge type ignition circuit is used. The capacitor discharge type ignition circuit includes, for example, an ignition capacitor that is provided on the primary side of the ignition coil and is charged by an ignition power source, and the electric charge of the ignition capacitor is conducted through the primary coil of the ignition coil that is conducted at the ignition timing of the engine. And a thyristor to be discharged. In order to prevent the ignition operation of such a capacitor discharge type ignition circuit, for example, when the safety switch is in an OFF state, the power supply coil that charges the ignition capacitor is short-circuited, or the ignition capacitor is connected to the ignition coil. A circuit for bypassing the trigger signal of the thyristor to be discharged through the primary coil may be provided.

  In the above-described embodiment, the control power supply circuit includes the first power supply capacitor that is charged almost instantaneously and the second power supply capacitor that is charged with a predetermined time constant with the voltage across the first power supply capacitor. Although the provided circuit is used, a control power supply circuit having only one power supply capacitor can be used.

  As in the above embodiment, a control power supply circuit that obtains a DC voltage by charging a power supply capacitor with the output of the ignition power supply coil is provided, and a power supply voltage for operating the safety circuit is obtained from the control power supply circuit. Then, in a situation where the battery cannot be used (when the battery is exhausted), the safety circuit can be activated even when the engine is started by a starter that is manually operated.

  In the embodiment shown in FIG. 1, the safety switch 3 may be connected between the output terminal 10b on the negative polarity side of the control power supply circuit and the cathode of the diode D5. In this way, the safety switch is connected. In this case, when the engine start switch 13 is closed, a large current flows from the battery 14 through the resistor R1 having a small resistance value and the diode D3, and the resistor R1 may be burned out. On the other hand, when the safety switch 3 is connected as in the embodiment shown in FIG. 1, no current flows through the resistor R1 when the engine start switch 13 is closed, and the resistor R1 burns out. There is no risk of such problems.

It is the circuit diagram which showed one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ignition circuit 2 Safety circuit 3 Safety switch 4 Ignition coil 5 Primary current control transistor 6 Transistor control circuit 7 Spark plug 8 Ignition prevention switch 9 Ignition prevention control switch 10 Control power circuit 11 Drive signal supply PUT
12 Relay 12Y Relay exciting coil 12a Relay normally open contact 13 Engine start switch 14 Battery 15 Starter motor

Claims (2)

An ignition circuit having an ignition coil and a primary current control circuit for controlling a primary current of the ignition coil, and inducing a high voltage for ignition in a secondary coil of the ignition coil at an ignition timing of the internal combustion engine; A safety switch that is maintained in an on state when a condition for allowing the engine to start is satisfied, and that is maintained in an off state when a condition for prohibiting the start of the internal combustion engine is satisfied; The ignition circuit is allowed to generate a high voltage for ignition when the safety switch is in an on state at the time of starting, and the ignition circuit is activated when the safety switch is in an off state at the time of starting the internal combustion engine. An ignition device for an internal combustion engine comprising a safety circuit that prevents generation of a high voltage for ignition,
A relay having a normally-open contact is provided, and an excitation coil of the relay is connected to both ends of the battery through the engine start switch and the safety switch which are closed during engine start operation;
A starter motor driven when starting the internal combustion engine is connected to both ends of the battery through the normally open contact of the relay and the engine start switch;
An ignition device for an internal combustion engine. An ignition coil that is provided in a magnet generator driven by an internal combustion engine and induces an AC voltage in a primary coil grounded at one end, and an ON state when a half-wave voltage of one polarity is induced in the primary coil A primary current control transistor provided so as to short-circuit the primary coil, and a primary current control circuit for controlling the primary current control transistor to be cut off at the ignition timing of the internal combustion engine. An ignition circuit for inducing a high ignition voltage in the secondary coil of the ignition coil when the primary current control transistor is cut off, and a condition for allowing the internal combustion engine to start is established. A safety switch that is kept in an on state when the engine is on and is kept off when a condition for prohibiting the start of the internal combustion engine is satisfied, The ignition circuit is allowed to generate a high voltage for ignition when the safety switch is on when the engine is started, and the ignition circuit when the safety switch is off when the internal combustion engine is started. An internal combustion engine ignition device comprising a safety circuit for preventing the circuit from generating a high voltage for ignition;
The safety circuit is
A control power supply circuit that generates a control DC voltage by including a power supply capacitor that is charged by the half-wave voltage of the other polarity when a half-wave voltage of the other polarity is induced in the primary coil of the ignition coil; A trigger signal input terminal is connected to the one end of the primary coil through a resistor and connected in parallel to the primary coil, and a trigger signal is given by a half-wave voltage of one polarity induced in the primary coil. An ignition prevention switch that is in a conductive state while the half-wave voltage of the one polarity is generated,
It is connected between the trigger signal input terminal of the ignition prevention switch and the other end of the primary coil, and conducts when a drive signal is given to prevent the trigger signal from being given to the ignition prevention switch. A switch for ignition prevention control;
The anode is connected through a resistor to the output terminal on the positive polarity side of the control power circuit, and the cathode is connected to the drive signal input terminal of the ignition prevention control switch, and a gate signal of an on level or higher is given between the anode gates. A drive signal supply PUT that conducts when the control power supply circuit provides a drive signal from the control power supply circuit to the ignition prevention control switch,
One end of the safety switch is grounded through a first diode with the cathode facing the ground side and is connected to an output terminal on the negative polarity side of the control power supply circuit through a current limiting element, and the other end of the safety switch is Connected to a circuit connected to the gate of the drive signal supply PUT through a second diode with the cathode facing the safety switch,
A relay having a normally open contact is provided and connected to both ends of a battery whose negative electrode is grounded through the engine start switch and the safety switch which are closed while the excitation coil of the relay performs the start operation of the engine,
A starter motor driven when starting the internal combustion engine is connected to both ends of the battery through a normally open contact of the relay and an engine start switch;
An ignition device for an internal combustion engine.

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