JPH0318700Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to an engine stopping device that stops an ignited engine using the engine's ignition circuit.

[Conventional technology]

Conventionally, in order to stop an engine, the engine's ignition circuit has been disabled. One of these means is shown in Japanese Patent Publication No. 59-45836 as shown in FIG. In FIG. 4, reference numeral 1 denotes a power generation coil of a magnet generator driven by an engine (not shown), and 2 a signal coil that generates an ignition signal at the ignition timing of the engine, which is built in, for example, the magnet generator.
3 is an ignition device that ignites the engine; for example,
This is a capacitor discharge type ignition device that ignites internally twisted engines.

In this ignition device 3, the power generation output of the power generation coil 1 is rectified by a diode 4, and a capacitor 5 is charged with the rectified output. A connection point between the diode 4 and the capacitor 5 is grounded via a thyristor 8 as a semiconductor switching element.

On the other hand, an ignition signal is applied from one end of the signal coil 2 to the gate of the thyristor 8 via a diode 10, and the other end of the signal coil 2 is connected to the anode side of the diode 6 as well as to the ground wire (GND) of the ignition device 3. It is grounded through.

The diode 10 is a diode that rectifies the ignition signal of the signal coil 2 and supplies it to the gate of the thyristor 8, and also prevents a reverse voltage from being applied between the gate and the cathode.

Further, the diode 6 is a diode that short-circuits a half cycle of the power generation output of the power generation coil 1 that does not contribute to charging the capacitor 5.

The primary example of ignition coil 7 is ground and capacitor 5
The secondary side is grounded via the spark plug 9.

The thyristor 8 receives an ignition signal from the signal coil 2 at the ignition timing of the engine, and energizes the ignition coil 7 with the charge in the capacitor 5.

The output end of the generator coil 1 is grounded via a thyristor 12 as a semiconductor switching element and a stop switch 11, and is connected to a resistor 13 and a constant voltage diode 1 as a constant voltage means.
It is connected to the ground wire (GND) through 5,
A diode 14 is connected between the connection point between the resistor 13 and the constant voltage diode 15 and the cathode of the thyristor 12.

The stop switch 11 is a switch that stops the engine by bypassing the power generation output of the power generation coil 1.

Further, the thyristor 12, the resistor 13, the diode 14, and the constant voltage diode 15 constitute a stop circuit.

Next, the operation will be explained. First, when the stop switch 11 is opened, the generated output of the generator coil 1 is rectified by the diode 4, charging the capacitor 5 and energizing the resistor 13 and the constant voltage diode 15.

Here, the resistor 13 only needs to flow the current necessary to trigger the thyristor 12, so it can have a relatively large value. Therefore, the current value flowing through the resistor 13 and the voltage regulator diode 15 can be small, so it is possible to generate electricity. The load on the power generation output of the coil 1 is small, and the charge on the capacitor 5 hardly decreases.

Further, since the voltage dividing point between the resistor 13 and the voltage regulator diode 15 is connected to the gate of the thyristor 12, the gate voltage (trigger voltage) of the thyristor 12 with respect to ground is equal to the voltage drop across the voltage regulator diode 15, for example 4V. Then it will be 4V.

The cathode voltage of the thyristor 12 is approximately the same as the gate voltage since no current flows between the gate and the cathode. Therefore, if the voltage drop across the voltage regulator diode 15 is, for example, 4V, the voltage across the terminals of the stop switch 11 will be as low as 4V.

As described above, when the stop switch 11 is opened, the capacitor 5 is reliably charged by the power generation output of the generator coil 1, the thyristor 8 is triggered by the output of the signal coil 2, and the charge of the capacitor 5 is transferred to the primary coil of the ignition coil 7. A spark discharge is generated in the spark plug 9, and the engine is operated.

Next, when stopping the engine, when the stop switch 11 is closed, the gate of the thyristor 12,
If the voltage drop of the constant voltage diode 15 is 4V, for example, 4V is applied between the cathodes. The gate voltage required to make the thyristor 12 conductive is generally about 0.5V to 0.7V, so if the voltage drop across the voltage regulator diode 15 is, for example, 4V, the thyristor 12 will become conductive in response to this voltage of 4V. Become.

As a result, the power generation output of the generator coil 1 is short-circuited through the thyristor 12 and the stop switch 11, so after the stop switch 11 is closed, the capacitor 5 is no longer charged, and even if the thyristor 8 is conductive at the engine ignition timing, the ignition coil 7 is Since no secondary voltage is generated, the engine will definitely stop.

[Problem that the invention attempts to solve]

Since the conventional stop device is constructed using semiconductor elements such as a constant voltage diode and a thyristor as described above, the ignition device 3 shown in FIG.
When a contact failure occurs in the grounding wire (GND) of the thyristor 8, the charge in the capacitor 5 becomes
As shown by broken lines, the gates and cathodes of the thyristor 8, the constant voltage diode 15, and the thyristor 12,
A large current of several tens of amperes flows through the stop switch 11, ground, and ignition coil 7 as shown by the broken line.
This has the disadvantage that the constant voltage diode 15 and thyristor 12 are destroyed, making it impossible to stop the engine or prevent the engine from igniting.

In addition, since the stop switch 11 normally serves as a key switch that turns on and off battery power as a power source for engine lighting, etc., if it is incorrectly connected, battery power may flow from the key switch and cause diode 1
4. A large current flows through the constant voltage diode 15, destroying the diode 14 and the constant voltage diode 15, resulting in the disadvantage that the engine cannot be stopped or the engine cannot be ignited.

This invention was made to solve these problems, and it is possible to eliminate the failure of semiconductor elements due to the large current as described above, and also to create an engine that can always maintain the voltage applied between the terminals of the stop switch at a low voltage. The purpose is to obtain a stopping device.

[Means for solving problems]

The stop device according to this invention includes a first blocking means for blocking the current passing through the constant voltage means and the gate and cathode of the semiconductor switching device, a means for limiting the current flowing from the input terminal of the semiconductor switching device, and a stop switch. A second blocking means for blocking the inflowing current is provided.

[Effect]

In this invention, the first blocking means, the limiting means, and the second blocking means prevent an abnormally large current flowing through the constant voltage means and the gate and cathode of the semiconductor switching element, and further The current flowing from the anode of the semiconductor switching element is limited, and the current flowing from the stop switch is blocked.

[Example of idea]

Hereinafter, embodiments of the engine stopping device of this invention will be described based on the drawings. In this Fig. 1, in order to avoid duplication, when explaining the configuration, the same parts as in Fig. 4 are given the same reference numerals.
The explanation will mainly focus on the parts that are different from FIG. 4.

In this figure, 16 is connected in series with the constant voltage diode 15, and the thyristor 1 is connected from the ground side.
A first blocking device whose anode is connected to the gate side of the thyristor 12 and its cathode is connected to the ground side so that the current flows from the gate side of the thyristor 12 to the ground side. A diode is the means.

Further, 17 is a resistor as a limiting means inserted between the anode of the thyristor 12 and the output end of the generating coil 1, and 18 is a resistor inserted between the cathode of the thyristor 12 and the non-ground terminal of the stop switch 11. A diode is the second blocking means. The other configurations are the same as in FIG. 3.

Next, the operation will be explained. First, when the stop switch 11 is opened, the generated output of the generator coil 1 is rectified by the diode 4, charging the capacitor 5, and energizing the resistor 13, constant voltage diode 15, and diode 16.

Since the voltage dividing point between the resistor 13 and the voltage regulator diode 15 is connected to the gate of the thyristor 12, the gate voltage of the thyristor 12 with respect to the ground is the sum of the voltage drop across the voltage regulator diode 15 and the voltage drop across the diode 16. .

In other words, the voltage drop of the constant voltage diode is V _Z
If the voltage drop across the diode 16 is V _D , then
It becomes V _Z + V _D. The voltage drop V _D of the diode 16 is generally about 0.7V, and the voltage drop V _Z of the constant voltage 15 is
Since it can generally be set arbitrarily above 0.7V,
The total voltage V _Z + V _D of these voltage drops is approximately 1.4V
It can be set arbitrarily from For example, if the total voltage V _D +V _Z of the voltage drops is 4V, the gate voltage of the thyristor 12 with respect to ground is 4V.

Diode 1 is connected from the cathode of thyristor 12.
However, since the stop switch 11 is open, no current flows between the gate and cathode of the thyristor 12, and therefore the thyristor 12 is not conductive. , the cathode current of the thyristor 12 does not flow.

As a result, the cathode voltage of the thyristor 12 becomes approximately the same potential as the gate voltage of the thyristor 12, no current flows through the diode 18, and there is no potential difference between the non-grounded terminal side of the stop switch 11 and the cathode of the thyristor 12. The voltage across the terminals of the stop switch 11 is the sum of the voltage drop across the constant voltage diode 15 and the voltage drop across the diode 16, V _Z +V _D . If the voltage V _Z +V _D is 4V, for example, it will be a low value of 4V.

Because of such a low voltage, even if water or seawater adheres to the stop switch 11, the leakage current is extremely small, so there will be no dielectric breakdown of the stop switch 11, and no risk of electric shock even if the stop switch 11 is touched. At the same time, there is no loss in the power generation output of the power generation coil 1, and there is no possibility that the generated voltage will drop and cause ignition failure.

As described above, when the stop switch 11 is opened, the capacitor 5 is reliably charged by the power generation output of the generator coil 1, the thyristor 8 is triggered by the output of the signal coil 2, and the charge of the capacitor 5 is transferred to the primary coil of the ignition coil 7. A spark discharge is generated in the spark plug 9, and the engine is operated.

Furthermore, even if the wiring on the non-grounded terminal side of the stop switch 11 comes into contact with the battery power supply or is incorrectly connected, and battery power is applied to the non-grounded terminal side of the stop switch 11, the diode 18 blocks this. , there is no damage to the stop device due to the application of power such as a battery power source.

Next, when the stop switch 11 is closed to stop the engine, the gate of the thyristor 12 receives a voltage V _Z +V _D , which is the sum of the voltage drops of the constant voltage diode 15 and the voltage drops of the diode 16, for example.
If it is 4V, 4V is applied. And thyristor 12 gates, cathode, diode 18,
Stop switch 11 and gate trigger current flow. When current flows through the diode 18, a voltage drop occurs, so the voltage V _GK between the gate and cathode of the thyristor 12 has a value expressed by the following equation.

V _GK = Voltage drop across the constant voltage diode 15 V _Z + Voltage drop across the diode 16 V _D - Voltage drop across the diode 18... (1) Since the voltage drop across the diode 16 and the voltage drop across the diode 18 are almost the same, the voltage drop across the thyristor 12
The voltage between the gate and cathode V _GK becomes the voltage drop V _Z of the voltage regulator diode 15, for example, V _Z
is 3.3V, the above-mentioned V _GK is 3.3V.

Usually, the gate trigger voltage of the thyristor used in this kind of stop circuit is 0.5V to 0.7V,
Since the V _GK has sufficient voltage to trigger the thyristor 12, the thyristor 12 becomes conductive.

As a result, the power generation output of the generating coil 1 is the resistance 1
7, the thyristor 12, the diode 18 and the stop switch 11 are short-circuited.

The resistor 17 is set to several hundred ohms or less so that the generated output can be sufficiently bypassed. Therefore, after the stop switch 11 is opened, the capacitor 15 is not charged, so even if the thyristor 8 conducts at the engine ignition timing, ignition will not occur. No secondary voltage is generated in the coil 7, so the engine will surely stop.

However, when a contact failure occurs in the ground wire of the ignition device 3, the charge in the capacitor 5 is transferred to the thyristor 8.
When conductive, the current from the ground side is blocked by the diode 16, so it flows through the thyristor 8 and the diode 6, passes through the resistor 13, and flows through the thyristor 12.
, the thyristor 12 becomes conductive, and the thyristor 8, diode 6,
It passes through the resistor 17, the anode and cathode of the thyristor 12, the diode 18, the ground of the stop switch 11, and the ignition coil 7.

The current flowing through this path is limited by the resistor 17. Thyristor 8, diode 6, and thyristor 1, which are semiconductor elements in the path through which this current flows.
2, and diode 18, the element with the smallest withstand capacity. Since the general current withstand capacity is about several tens of amperes, the resistance value of resistor 17 is set to the thyristor 8, diode 6,
By setting the current to a value that is less than or equal to the smallest current withstand capacity of the thyristor 12 and the diode 18, the thyristor 8, the diode 6, the thyristor 12, and the diode 18 can be prevented from being destroyed. As an example, the maximum value of the current flowing through the path of thyristor 8, diode 6, thyristor 12, diode 18, stop switch 11, ground, and ignition coil 7 is I _P , and the charge of capacitor 5 with respect to the resistance value of resistor 17 is shown in the graph. An example is shown in Figure 2.

In this example, if the resistance value is 10Ω or more, it will be less than the current withstand capacity of the smallest of thyristor 8, diode 6, thyristor 12, and diode 18, so if the resistance value of resistor 17 is 10Ω to several hundred Ω
If this setting is made, the semiconductor elements of thyristor 8, diode 6, thyristor 12, and diode 8 will be destroyed.

In addition, in the above embodiment, 17
is connected between the anode of the thyristor 12 and the output end of the generating coil 1, and the resistor 13 is connected between the output end of the generating coil 1 and the gate of the thyristor 12. Like resistance 17
is connected between the output end of the generating coil 1 and the anode of the thyristor 12, and the resistor 13 is connected between the output end of the generating coil 1 and the anode of the thyristor 12.
It may also be connected between the anode and the gate, and the same effect as in the above embodiment can be obtained.

[Effects of the invention] As explained above, this invention provides a stop device in which a constant voltage means is connected to the control pole of the semiconductor switching element and the other end of the generator coil, and the voltage applied between the terminals of the stop switch is always maintained at a low voltage. a first blocking means for blocking abnormal current flowing from the ground side of the stop switch through the constant voltage means to the control pole of the semiconductor switching element; a means for limiting current flowing from the input terminal of the semiconductor switching element; and a means for blocking current flowing from the stop switch. Since the second blocking means is provided, the current flowing from the anode of the semiconductor switching element through the constant voltage means can be limited, and the current flowing from the stop switch can be blocked.
Therefore, it is possible to prevent damage to the constant voltage means and semiconductor switching elements constituting the stop device.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of an embodiment of the engine stopping device of this invention, Fig. 2 is a characteristic diagram showing the relationship between the resistance value and current of the blocking means in the engine stopping device of the above invention, and Fig. 3 is a circuit diagram of an embodiment of the engine stopping device of this invention. FIGS. 4 and 5 are circuit diagrams showing other embodiments of the engine stopping device. FIGS. 4 and 5 are circuit diagrams of conventional engine stopping devices, respectively. 1...Generating coil, 2...Signal coil, 3...
Ignition device, 4, 6, 10, 14, 16, 18...
Diode, 5... Capacitor, 7... Ignition coil, 18, 12... Thyristor, 11... Stop switch, 13, 17... Resistor, 15... Constant voltage diode. In the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A generator coil of a magnet generator, an ignition circuit that receives the output of the generator coil and generates an engine ignition voltage for the ignition coil, and an input terminal connected to one end of the generator coil. a semiconductor switching device having an output end and a control pole; a stop switch connected to the output end and the other end of the power generation coil; a stop switch connected to the control pole and the other end of the power generation coil; a constant voltage means for constant voltage applied to the control pole of the semiconductor switching element; a first blocking means for blocking current passing through the constant voltage means and the control pole and output terminal of the semiconductor switching element; means for limiting the current flowing through the input of the element;
and second blocking means for blocking current flowing from the stop switch. (2) The engine stopping device according to claim 1, wherein the first blocking means is a diode. (3) The engine stopping device as set forth in claim 1 of the utility model registration claim, wherein the limiting means is resistance. (4) The engine stopping device according to claim 1, wherein the second blocking means is a diode.