JPH0521661Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to an ignition device for an internal combustion engine, and is particularly intended to prevent malfunctions that occur when the engine is reversed.

[Conventional technology]

Figures 5 and 6 show a conventional ignition system as shown in, for example, Japanese Utility Model Publication No. 53-25054. In Figure 5, 1 is a flywheel that rotates in synchronization with the engine, and 1a is a flywheel that rotates in synchronization with the engine. A protrusion 2 provided on the flywheel 1 is a pickup comprised of a magnet and a coil (both not shown) that generate advance angle signals and retard angle signals in response to changes in the magnetic field caused by the protrusion 1a. Further, in FIG. 6, 3 is a generator coil housed in a magnet generator that generates an electromotive force according to the rotation of the engine, 5 is a diode 4, and a capacitor that charges the ignition voltage from the generator coil 3 through the ignition coil 12. 7, 8, 9, and 10 are diodes that rectify the AC voltage generated in the pickup 2; 11 is a resistor connected to the diode 7;
6 is a thyristor that discharges the charge of the capacitor 5 to the ignition coil 12, and the gate is equipped with a resistor 1.
1. Diode 9 is connected.

Next, the operation will be explained. First, when the flywheel 1 is rotating normally (clockwise) as shown in FIG. 5, at the positions shown in FIG. 5A and FIG. Generates voltage. The positive voltage that is the advance angle signal is applied to the gate of the thyristor 6 through the diode 10, the diode 7, and the resistor 11, and the negative voltage that is the retard angle signal is applied to the gate of the thyristor 6 through the diode 8 and the diode 9. By the way, when the engine is started, the rotation of the flywheel 1 is low, so the output voltage of the pick-up 2 is also low, and the positive voltage that is the advance angle signal of the pick-up 2 is lowered by the resistor 11 and becomes as shown in Fig. 7b. As shown, the trigger voltage V _T of thyristor 6 cannot be reached,
On the other hand, since the negative voltage that is the retard signal is applied directly to the gate of the thyristor 6 through the diode 9, a voltage higher than the trigger voltage V _T is supplied, triggering the thyristor 6 to conduct. Therefore, in the retard position, the capacitor 5
The electric charge is discharged, and an ignition voltage is generated by the ignition coil 12 to start the engine. next,
After the engine starts, the positive voltage that is the advance angle signal increases as the rotation increases, and the trigger voltage of thyristor 6 V _T
When the thyristor 6 reaches the advanced angle position, the thyristor 6 is triggered by the advance angle signal, and the ignition voltage is generated at the advanced angle position, so that the engine rotates more stably.

[Problem that the invention attempts to solve]

Since the conventional ignition device is constructed as described above, it has the following drawbacks. Generally, the retard signal is set near the top dead center of the engine in consideration of startability, and when starting, the retard signal is set at the position shown in Figure 5A to the position where the retard signal is generated as shown in Figure 5B. When the rotation is reversed again to the position shown in FIG. 5A due to the compression pressure of the engine, a retardation signal is generated at the advanced angle position during forward rotation, as shown in FIG. 7c. Since this signal is in the same direction as the retard signal during forward rotation, the voltage becomes higher than the trigger voltage V _T as shown in FIG. 7d, and the thyristor 6 is triggered to generate an ignition voltage. At this time, when the engine was in the reverse direction, it would be after top dead center, which caused problems such as incorrect explosions and problems such as butts and backfires.

This invention was made to solve the above-mentioned problems, and the object is to provide an ignition device for an internal combustion engine that can prevent incorrect ignition that causes sparking, backfire, etc. at the time of starting.

[Means for Solving the Problems] The ignition device according to this invention includes a first signal generating means for generating an advance angle signal and a retard angle signal, and a signal generating means that generates a signal at the same time as the retard signal when the engine rotates forward. A second signal generating means is provided which generates a signal at a different time from the retard signal produced by the first signal generating means when the engine is retarded, and when the engine is retarded, the second signal generating means signal retards the retard angle when the engine is reversing. It is configured to disable the signal and prevent the generation of ignition voltage.

[Effect]

The ignition device in this invention generates an ignition voltage by the retard signal in the first signal generator when the engine rotates forward based on the signal from the second signal generator, and disables the retard signal when the engine rotates in reverse. The engine is configured to prevent the generation of ignition voltage, making it possible to prevent unauthorized explosions of the internal combustion engine.

[Example of idea]

An embodiment of this invention will be described below with reference to the drawings. In FIG. 1, 1a and 1b are a first protrusion and a second protrusion formed on the outer periphery of the flywheel 1, respectively, and 2 is a first pick-up disposed corresponding to the first protrusion 1a. This forms a first signal generating means that generates an advance angle signal and a retard angle signal by passage of the first protrusion 1a. Reference numeral 13 denotes a second pickup disposed corresponding to the second protrusion 1b, and a second signal generator configured to generate a signal at the same time when the first pickup 2 generates a retarded signal. forming means. Note that the protrusions 1a, 1b and the pick-ups 2, 1
3 are arranged offset in the axial direction so as not to interfere with each other, as shown in FIG. 1B. Further, in FIG. 2, the same reference numerals as in FIG. 6 indicate the same configuration, and 14 is a diode for rectifying the output of the second pickup 13, and 15 is a diode 14.
thyristor triggered by a signal by
6 is a transistor whose emitter and collector are connected between the diode 9 and the gate of the thyristor 6; 17 is a resistor connected between the base of the transistor 16 and the anode of the thyristor 15; Next, the operation will be explained based on FIGS. 3 and 4. When the flywheel 1 is rotating forward (clockwise), the first pickup 2 at the position A in FIG. 3 generates an advance signal as shown in FIG. 4A, and the diodes 7 and 10 , is supplied to the gate of the thyristor 6 via the register 11. This voltage causes a voltage drop by the resistor 11, and when the engine is started, the thyristor 6 does not conduct because it does not reach the trigger voltage V _T as shown in FIG. 4c. At this time, the second pick-up 13 is connected to the second protrusion 1b.
Do not face the person and do not generate a signal. Next, Figure 3B
When rotated to the position shown in FIG. 4, the first pickup 2 generates a negative voltage as a retard signal, and the second pickup 13 generates a positive voltage, as shown in FIGS. 4a and 4b. The voltage from the first pickup 2 is supplied to the emitter of the transistor 16 via the diodes 8 and 9, and at this time the voltage from the second pickup 13 is supplied to the emitter of the transistor 16.
Since the voltage V T maintains the thyristor 15 in a conductive state, the transistor 16 becomes conductive, and as shown in _FIG .
is applied to make the thyristor 6 conductive, and an ignition voltage is generated as in the conventional case.

Furthermore, when moved to the position shown in FIG. 3c, no voltage is generated from the first pickup 2 and the thyristor 6 is not rendered conductive. Note that although a negative voltage is generated in the second pickup 13, it is blocked by the diode 14.

Next, a case will be described in which the engine is unable to overcome compression top dead center during startup and is reversed. That is,
When the flywheel 1 rotates counterclockwise from the position shown in Fig. 3c to the position shown in Fig. 3B, a positive voltage is first generated in the second pickup 13, and then a negative voltage is generated as shown in Figs. Voltage is generated. Here, when a negative voltage is generated, a positive voltage, which is an advance angle signal, is generated in the first pickup 2 and is supplied to the thyristor 6 via the resistor 11.
As shown in FIG. 4f, the thyristor 6 is not triggered because the trigger voltage is below V _T .
Furthermore, when the first pickup 2 reaches the position shown in FIG. The transistor 16 is not conductive, and the thyristor 6 has the first
A retard signal from the pickup 2 is not supplied. That is, when the engine rotates in the forward direction, the retard signal from the first pickup 2 is output to the thyristor 6 to generate the ignition voltage, and when the engine rotates in the reverse direction, the generation of the ignition voltage is prevented by the signal from the second pickup 13. This makes it possible to prevent unauthorized explosions.

In the above embodiment, an ignition device was described in which the advance angle signal and the retard angle signal are applied to the gate of the thyristor 6 to perform the jump advance angle, but the advance angle calculation is performed continuously using the advance angle signal as the calculation input. The same can be applied to electronic advance ignition devices.

[Effect of idea]

As described above, according to this invention, the second signal generation means is provided, and the signal is generated at the same time as the retard signal during forward rotation by the first signal generation means, and is different from the retard signal during reverse rotation. Generating a signal at the specified time has the effect of preventing unauthorized explosions when the engine is reversed.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an ignition system according to an embodiment of this invention, Fig. 2 is a circuit diagram showing an ignition system according to an embodiment of this invention, and Figs. 3 and 4 are diagrams showing an ignition system according to an embodiment of this invention. FIG. 5 is a configuration diagram showing a conventional ignition device; FIG. 6 is a circuit diagram showing a conventional ignition device; FIG.
The figure is a waveform diagram illustrating the operation of a conventional ignition device. In the figure, 1 is a flywheel, 1a is a first protrusion, 1b is a second protrusion, 2 is a first pickup, 3 is a power generation coil, 4, 7, 8, 9, 10, 1
4 is a diode, 5 is a capacitor, 6 and 15 are thyristors, 11 and 17 are registers, 12 is an ignition coil, 13 is a second pickup, and 16 is a transistor. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A first signal generating means that generates an advance angle signal and a retard angle signal for the engine in response to a magnetic change caused by a first protrusion provided at a predetermined position of a flywheel that rotates in synchronization with the rotation of the engine, and engine starting. An ignition means that sometimes generates an ignition voltage by a retard signal to start the ignition, and receives a magnetic change due to a second protrusion provided at a position that does not magnetically interfere with the first protrusion of the flywheel. When the engine rotates normally, the first
a second signal that generates a signal at the same time as the retard signal outputted by the signal generating means, and generates a signal at a different time than the retarded signal outputted from the first signal generating means when the engine is reversed; generating means, based on the signal of the second signal generating means, generates an ignition voltage by the retard signal when the engine rotates in the forward direction, and disables the retard signal to generate the ignition voltage when the engine rotates in the reverse direction; An internal combustion engine ignition device, characterized in that it is equipped with means for blocking.