JPS60113070A - Ignition device for internal-combustion engine - Google Patents

Abstract

PURPOSE:To immediately stop an internal-combustion engine to aim at enhancing the safety of operation of the engine, by determining the driving direction of the engine in accordance with the ordering pattern of generated voltages of generators for the engine so that when the driving direction is reverse, the operation of ignition is electrically nullified. CONSTITUTION:When an internal combustion engine is driven in the reverse direction, an induced voltage at a first winding T1 is such that the polarity of electric wave is reversed, and therefore, a voltage charged into a capacitor C1 is also reversed in the polarity of electrical wave form. Therefore, upon completion of one-time ignition the electrical charge of the capacitor C1 is charged with reverse polarity. Accordingly, a capacitor C2 for charging electrical charge into the capacitor C1 is charged with a voltage V3 with reversed polarity, and a semiconductor switching element 4 is maintained in a trigger-like condition so that the short circuit is established and held between the gate and cathode of a thyristor 3, thereby the ignition operation of an ignition circuit cannot be attained. Therefore, if the internal combustion engine is driven in the reverse direction, the ignition circuit is at once stopped, so that the engine is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a non-contact ignition device for an internal combustion engine configured using a semiconductor switching element. The purpose of this is to immediately stop the engine in the event of an accident.

A large number of small general-purpose engines are used in the field of motor vehicles, and currently, the biggest problem with these small general-purpose engines is that they are illegally driven in the opposite direction.

If the engine is driven in the opposite direction, not only will normal operation be impossible, but it will also be extremely dangerous.

For this reason, some internal combustion engines of this type are equipped with an emergency stop function so that the engine can be stopped immediately if a malfunction such as reverse rotation occurs in the engine.

However, if the engine is driven in the opposite direction, the risk of production is extremely high, and the shock caused by the operation in the opposite direction is intense, so the above-mentioned operation to stop the engine cannot be accomplished quickly. This could not be done and there was a great risk of a major accident.

The present invention was devised to eliminate the drawbacks of the conventional examples described above, and in a high-voltage magnet generator for an internal combustion engine, the direction of the two generated voltages is set according to the driving direction of the internal combustion engine.
By taking advantage of the fact that it follows a certain sequential pattern, the driving direction of the internal combustion engine is determined based on the sequential pattern of the generated voltage.
Therefore, depending on the direction of the generated voltage, one ignition operation itself is electrically disabled when driving in the opposite direction.

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

The ignition device for an internal combustion engine according to the present invention has a first resistor R1 having a high resistance value, a transistor 1, and a first a series circuit with a capacitor CI, and a series circuit with a transistor circuit 2 and a second resistor R2 having a low resistance value;
A silicon-controlled rectifying element 3 (hereinafter referred to as f
thyristor 3) are connected in parallel, the heath of the transistor 1 is connected to the emitter of the transistor circuit 2, the collector of the transistor 1 is connected to the gate of the thyristor 3, and the transistor circuit 2 is connected to the anode of the thyristor 3, a semiconductor switching element 4 with a control terminal is connected in parallel with the gate circuit, and a resistor R6 and a second capacitor C2 are connected in series in parallel with the first capacitor CI. The circuit is connected, and the connection point between the resistor R6 and the second capacitor C2 is connected to the control terminal of the switching element 4.

The configuration of the gate circuit of the thyristor 3 is completely different depending on whether it is a self-trigger type or an external trigger type.1 In the present invention, what is the configuration of the gate circuit of the thyristor 3? In the illustrated embodiment, a case is shown in which the resistor R5 has the simplest structure.

In the device of the present invention described above, the first resistor R1° transistor 1. First capacitor C1, I - Lancisk circuit 2. The second resistor R2, the third resistor R3, and the thyristor 3 constitute the main body of one ignition device, and one semiconductor switching element4. resistor and second capacitor C
2 constitutes a part that prevents the engine from reversing.

Furthermore, although the semiconductor switching element 4 is not limited to ships, the most desirable ones are field effect transistors and ordinary transistors.

1 and 3 show an example of a circuit configuration using a field effect transistor as the semiconductor switching element 4, and FIGS. An example of a circuit configuration using i:1IT1 transistors is shown.

As is clear from the embodiments shown in FIGS. 1 to 4, in the case of the present invention, when a field effect transistor is used as the semiconductor switching element 4, one circuit is better than when an ordinary transistor is used. The configuration is simple.

The embodiment shown in FIG. 1 shows the most complex example of circuit configuration when a field effect transistor is used as the semiconductor switching element 4. The Zener diode ZD in the reverse direction inserted and connected between the transistor circuits 2 and 1 is for protecting the transistor circuit 2 from the surge voltage generated during the ignition operation.
The diode DI whose cathode is connected is used to cause a current in the reverse direction to flow through the transistor 1 to the primary winding T1, thereby preventing the occurrence of pre-spark.

The embodiment shown in FIG. 2 is constructed using f transistors in place of the field effect transistors in the embodiment shown in FIG. R9, and a series circuit consisting of a diode D3 and a resistor R8 that maintain the conduction state of the transistor are additionally required.

In the embodiment shown in FIGS. 3 and 4, the primary I plot Tl
In place of the diode DI in the circuit shown in FIG. 1 and the circuit shown in FIG.

A series circuit of a diode D2 and a resistor R7 is provided as a dedicated circuit.

The ignition device according to the present invention has the above-mentioned configuration, and first, the operation of the ignition device according to the present invention will be explained in order.

(Hereinafter, it will be explained according to the embodiment shown in FIG. 1) Inner MA
When the engine is driven in the forward rotation direction, an induced voltage V as shown in FIG. 5 is induced in the primary winding T1 of one ignition coil T.

When the forward voltage bone v2 starts to be induced, the third resistance R
Since the base current flows into the base of the transistor circuit 2 through the transistor circuit 2, the transistor circuit 2 is turned on.

By turning on transistor circuit 2.

1 through this transistor circuit 2 and the second resistor R2.
At the same time as this primary short circuit current flows, current also flows into the base of transistor 1, so transistor 1 is also turned on, and the first capacitor C1 is charged with the polarity shown in the figure. to charge.

When the charging in the first capacitor CI progresses and the potential of the emitter of the transistor 1 becomes approximately the same as the potential of the base, the transistor 1 enters a cut-off state.

When the transistor l is cut off, the collector potential of the transistor 1 rises rapidly to generate a voltage pulse, which is applied to the gate of the thyristor 3 through the stabilizing resistor 174, so that the thyristor 3 becomes conductive.

The conduction of the thyrisk 3 causes the base current of the transistor circuit 2 to be bypassed, which causes the transistor circuit 2 to turn off and abruptly interrupt the primary short-circuit current.

This sudden interruption of the primary short-circuit current causes one ignition coil T
A high voltage is induced in the secondary winding T2 of the plug P.
Spark discharge occurs and ignition is achieved.

The operation of the ignition circuit is achieved as described above, but as is clear from FIG. plays a unique role.

That is, a portion of the first voltage line v1 is charged to the first capacitor C1 with a polarity opposite to the polarity shown in FIG. The second resistor R2 → l - base of transistor 1 - emitter of transistor 1 Discharges its charge in the path of the first capacitor C1, so that transistor 1 enters the triggered state and at the same time as transistor circuit 2 turns on. It will surely turn on and the 9-circuit operation will be reliably achieved.

Further, the third voltage bone v3 also has the same effect as the first voltage bone v1.

Since the first capacitor C1 has an extremely small capacity, the change in the charging voltage charged to the first capacitor C1 draws a changing waveform as shown in FIG.

That is, the first capacitor C1 has a first voltage V
1 causes the voltage ν1, and the second voltage bone v2 causes the voltage ν2
However, the voltage v3 is charged correspondingly by the third voltage bone v3.

The voltage v3 out of the voltages charged in the first capacitor C1 is charged with a polarity opposite to that shown in FIG. 1 before the fifth ignition operation starts.

First capacitor C1→second capacitor 02←resistance R
6-Discharge in the path of the first capacitor C1 and charge the second capacitor C2 with the polarity shown.

When the second capacitor C2 is charged with the polarity shown, the semiconductor switching element 4 is kept turned off and does not affect the switching operation of the thyristor 3, so that the ignition circuit can operate normally. It will work.

Zunawaji, when a field effect transistor is used as the semiconductor switching element 4, the second capacitor C2
Due to this action, the potential of the gate of this field effect transistor is held at a lower potential than the potential of the source.5 This potential relationship causes the field effect transistor to be held in a state where it cannot be turned on. Similarly, when an ordinary transistor is used as the semiconductor switching element 4, this transistor is kept in a state where it cannot be turned on by the action of the electric charge stored in the second capacitor C2. That's what happens.

Next, the internal combustion engine was illegally driven in the opposite direction.
The induced voltage in the second winding T1, as shown in FIG. 7, is the polarity of the voltage waveform shown in FIG. The polarity of the voltage waveform shown in FIG. 6 is reversed.

Therefore, the first
The polarity of the charge on the capacitor C1 is opposite to that in the above state, that is, the polarity shown in the figure. It becomes two.

Therefore, the second capacitor C2, which charges the discharged charge of the first capacitor C1, is charged with the third voltage v3 with a polarity opposite to that shown in FIG.

By charging the second capacitor c2 with a polarity opposite to that shown in the figure, the semiconductor switching element 4 is held in the triggered state, and therefore the gate and cathode of the cyrisk 3 are always kept in a short-circuited state. The ignition circuit achieves its ignition operation.

It becomes impossible to do so.

For this reason, as soon as the internal combustion engine is driven in the reverse direction, the ignition operation stops, making it impossible to drive the internal combustion engine in the reverse direction, and the internal combustion engine stops.

As described above, the ignition device according to the present invention is configured to monitor the form of the induced voltage in the primary winding T1 and stop the operation of the ignition circuit by reversing the potential relationship corresponding to this change in form, so that the operation can be improved. This makes it possible to obtain safer operation of the internal combustion engine.

In addition, its circuit configuration includes two normal ignition circuits, a semiconductor switching element 4, a resistor R6, and a second capacitor C.
Since the structure is simply an addition of a series circuit with 2, the circuit configuration is not only simple but also inexpensive to manufacture, and the present invention can be easily implemented in existing ignition circuits. I can do it.

Furthermore, since the function of the device according to the present invention is activated when an induced voltage is generated in the primary winding T1, it will be activated as soon as an illegal reverse operation occurs in the internal combustion engine. This means that the internal combustion engine can be stopped with almost no adverse effects caused by reverse rotation of the internal combustion engine.

As is clear from the above explanation, the ignition device according to the present invention has a simple structure, is easy to manufacture, can be manufactured at low cost, and has an accurate and reliable anti-reversal function. Since this is achieved automatically, it exhibits many excellent effects such as being able to operate the internal combustion engine extremely safely.

[Brief explanation of drawings]

1 to 4 are electric circuit diagrams showing two embodiments of the present invention, and FIGS. 1 and 3 show an example in which a field effect transistor is used as a single semiconductor switching element.
FIGS. 2 and 4 show examples in which ordinary transistors are used as semiconductor switching elements. 5 to 8 are voltage waveform diagrams for explaining the operation of the device of the present invention, and FIGS. 5 and 6 show the state when the internal combustion engine is normally operating. 7 and 8 show the situation when the internal combustion engine is driven in the opposite direction. Explanation of symbols 1; transistor, 2; transistor circuit, 3; silicon resistor, 4; semiconductor switch notching element, R1゜R2,R
3, R4, [15, R6, R7, R8, R9i resistance, -
CLc2; Continuous Vl, V2, V3; Voltage. vLv2 +v3; voltage. Applicant Mei 1) Electrical Machinery Industry Co., Ltd. 44η

Claims (1)

[Claims] A first resistor with a high resistance value, a transistor and a first
A series circuit with a capacitor, a series circuit with a transistor circuit and a second resistor with a low resistance value, and a series circuit with a third resistor with a high resistance value and a silicon-controlled rectifier element with a gate circuit inserted between the gate and cathode. and a series circuit are connected in parallel, the base of the transistor is connected to the emitter of the transistor circuit, the collector of the transistor is connected to the gate of the silicon controlled rectifier, and the base of the transistor circuit is connected to the anode of the silicon controlled rectifier. connect to,
A semiconductor switching element with a control terminal is connected in parallel with the gate circuit, a series circuit of a resistor and a second capacitor is connected in parallel with the first capacitor, and a connection point between the resistor and the second capacitor. An ignition device for an internal combustion engine, which is connected to a control terminal of a semiconductor switching element.