JPS5941339Y2 - door device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement in an internal combustion engine ignition system, particularly in an internal combustion engine ignition system that uses a generating coil of a magnet generator as a power source.

First, the conventional example shown in FIGS. 1 and 2 will be explained.
In the figure, 1 is a magnet generator, 1a is a flywheel rotated by the engine, 1b and 1c are flywheels 1
Permanent magnet 1b is attached in the radial direction by two permanent magnets and holes installed at equal intervals inside a,
The small pole 1c is not magnetized.

1d is a generator iron core installed on the base of the magnet generator 10 (not shown), and its pair of pole faces are connected to the permanent magnet 1b and the pole 1.
c through the cap.

1e is a power generation coil that also serves as the primary coil of the ignition coil wound around this iron core 1d, and outputs AC output, that is, output in one direction (a shown by a solid line) and the other direction (b shown by a broken line) with mutually different polarities. occurs.

1f is a secondary coil of the ignition coil similarly wound around the iron core 1d; 2 is a first transistor which is a switching element that generates a high voltage by intermittent current flow in the a direction of the generator coil 1e; 3 is a second transistor that controls on/off of the first transistor 2; 4 is a resistor for causing a base current to flow through the first transistor 2; 5 and 6 are:
A voltage dividing resistor 7.8 for determining the operating point of the second transistor 3 is a resistor and a diode connected in series to both ends of the power generating coil 1e. Configure a series circuit that bypasses the direction output.

Next, this operation will be explained using a two-cycle engine as an example.

The power generating coil 1e provided in the magnet generator 1 which rotates in synchronization with the internal combustion engine has the power generating coil 1e shown in FIG. An AC output indicated by II, that is, an electromotive force indicated by solid line a and point 1b is generated.

Now, at the time of ignition timing of the engine, when an electromotive force is generated in the a direction in the generator coil 1e, the base current flows through the resistor 4 and the first transistor 2 is turned on, and current flows in the a direction of the generator coil 1e. is the first transistor 2
shorted through.

Then, when the engine ignition timing occurs and the terminal voltage of the resistor 6 divided by the voltage dividing register 5.6 rises to a predetermined value, the base current flows through the second transistor 3 and the second transistor 3 is reversed from OFF to ON state. The base current of the first transistor 20 flowing through the resistor 4 is shunted through the second transistor 3, so that the first transistor 2 is abruptly reversed to the off state and the energizing current of the generator coil 1e is turned off. cut off the flow.

This rapid current change generates an ignition voltage in the secondary coil 1f, and in response to this ignition voltage, a spark plug (not shown) discharges a spark.

Next, when a b-direction electromotive force that is not used for ignition is generated in the generator coil 1e, the current flowing in this direction is shunted by a series circuit consisting of a resistor I and a diode 8 connected in parallel to both ends of the generator coil 1e. The b-direction electromotive force is suppressed to a small value by the resistor 1.

Here, a occurs at both ends of the generating coil 1e.

Considering the electromotive force in the direction b, as described above, two cycles of alternating current output are generated in the generator coil 1e for one rotation of the engine, and are used for ignition.

An ignition voltage is generated in the secondary coil 1f at a voltage A corresponding to the engine ignition timing in the a-direction electromotive force, and no ignition voltage is generated at other small voltages.

In addition, the electromotive force in the direction b, which is not used for ignition, is bypassed by a series circuit consisting of a resistor I and a diode 8, and as a result,
The voltage generated before and after the ignition timing (dotted-dash lines, c, in FIG. 3I) is suppressed to the voltage value shown by the solid lines', c'.

By the way, in a series circuit consisting of the resistor 1 and the diode 8, that is, when the load is not connected to the generator coil 1e, the electromotive force in the b direction generates a dog voltage as shown by the 7-dot chain line in Figure 3. Therefore, the secondary coil 1f has a voltage of 2 depending on the change in the dog voltage (dotted chain line) of the generating coil 1e.
The next voltage is induced, causing unnecessary sparks to fly to the spark plug at times other than the normal ignition timing, that is, before and after the ignition timing.

In particular, if an unnecessary spark occurs before the engine ignition timing, that is, during the engine intake and compression process, the gas inside the cylinder will
Combined with low compression, the fuel consumption is KL.

There are defects that not only adversely affect the engine, but also make it impossible to drive the engine.

Therefore, by connecting a series circuit consisting of a resistor I and a diode 8 to both ends of the generator coil 1e, the b-direction voltage that occurs before the normal ignition timing is suppressed to a small voltage that does not cause sparks to fly to the spark plug. We try not to have a negative impact on the institution.

However, in this case, the b-direction voltage (dotted chain line) of the generator coil 1e is suppressed to the voltage shown by the solid line due to the heat consumption of the resistor 1, so the heat generation of the resistor γ becomes extremely large. 1 is also large in size, the unit to be housed together with the transistors 2, 3, etc. that constitute the ignition circuit becomes extremely large.

Furthermore, there is a risk that other elements may be destroyed due to the heat generated by resistor 1. To solve this problem, resistor 7 with good heat dissipation is used.
There are issues such as the selection of the mounting position of the unit and the need for a heat dissipation structure for the unit.

This idea was made to eliminate the above defects.
The output of the other polarity of the generator coil that occurs before the engine's ignition timing is consumed by the register and suppressed to a small value, and the output of the other direction of polarity that occurs after the ignition timing controls the semiconductor switching element to be in the ON state. By bypassing the output force of the other polarity having a large output value and eliminating consumption by the resistor, generation of unnecessary sparks before the regular ignition timing is prevented and heat generation of the resistor is reduced. This is an internal combustion engine ignition system that can.

Hereinafter, a detailed description will be given with reference to the embodiment shown in FIG. 4. In the figure, reference numeral 9 denotes a thyristor, which is a semiconductor switching element connected in parallel to a series circuit of a resistor I and a diode 8; 11.1
2 is a resistor and a capacitor connected in series with each other and similarly connected in parallel through a diode h'io to the series circuit of resistor T and diode 8; 13 is a resistor and a capacitor connected between the connection point of this resistor 11 and capacitor 12 and the gate of thyristor 9; It is a constant voltage diode that determines the connected force and the ON timing of the thyristor 9, and its threshold voltage VZ is set to be slightly larger than the b-direction voltage that occurs before the ignition timing.

14 is a resistor that forms a discharge path for the capacitor 12, and the time constant of the discharge path is small.
The control operation of the b-direction output, which is not used for e-ignition, will be described below.

The b-direction electromotive force generated before the ignition timing is shunted by the resistor 7 and diode 8 as in the conventional example, and its voltage port is suppressed from the dashed dot line to the voltage port' shown by the solid line in FIG. 3I. The current is applied according to the shaded area in Figure 3 (■).

Therefore, no high voltage is generated in the secondary coil 1f, and no unnecessary sparks are generated in the ignition plug.

At this time, the capacitor 12 is charged through the diode 10 and the resistor 11, but since the charging voltage does not reach the threshold voltage VZ of the Zener diode 13 or higher, the thyristor 9 continues to be in an off state without applying a gate signal. do.

The charge in the capacitor 12 is completely discharged through the resistor 14 during the generation period of the a-direction output.

Next, the b-direction electromotive force generated after the ignition timing is suppressed without being bypassed by the resistor I as described below.

Here, since the magnetic pole structure of the magnet generator 1 has unequal magnetic poles as shown in FIG. 1, the b-direction voltage C generated after the ignition timing has a voltage value that is smaller than that of the voltage port, and therefore the resistor r
If the voltage is bypassed by the ignition timing, the suppressed voltage C' will have a smaller value (voltage waveform) than the voltage S which was suppressed before the ignition timing.

Now, when voltage C in direction b occurs after the ignition timing, the voltage /-! across resistor 1 and diode 8 is generated. occurs,
Based on this voltage, capacitor 12 is connected to diode 1
0, it is charged through the resistor 11.

The charging voltage of this capacitor 12 is the constant voltage diode 13
When the threshold voltage VZ is reached, a gate signal is applied to the thyristor 9 and the thyristor 9 is inverted to the on state.

Then, the current flowing through resistor 1 and diode 8 (
The shaded area shown in Figure 3 (■) is bypassed by the thyristor 9 and is passed as a short-circuit current. Therefore, the power consumption by the resistor 7 is almost zero, and only the voltage drop of the thyristor 9 is present at both ends of the generating coil 1e. appears, resulting in an extremely low voltage, and no high voltage is generated in the secondary coil 1f.

Here, the turn-on timing of thyristor 9 is determined by the increase in engine speed (
If the short-circuit current increases, the generator coil 1e will be greatly affected by the armature reaction, which will adversely affect the output in the A direction, especially the A voltage used for ignition, and the ignition timing will be affected. There is a fear that prevents the generation of ignition voltage.

However, the embodiment of the present invention also solves the above-mentioned problems.

This solution will be explained in detail with reference to FIG. 5. Let the voltage waveform at low rotation of the engine be Vnl, and its period be T1.

On the other hand, the voltage waveform when the engine rotates at high speed is Vnz, and its period is T2.

As is well known, as the rotational speed increases, the period becomes shorter.

Additionally, due to the time constant of the charging circuit for the capacitor 12, a delay of a predetermined time is required for the charging voltage of the capacitor 12 to reach the threshold voltage VZ of the voltage regulator diode 13.

Now, the voltage across the resistor 7 and the diode 8 (substantially the voltage across the generator coil 1e) becomes Vnl, and the voltage waveform of the capacitor 12 becomes Vcl, and this voltage vc1 is equal to the threshold voltage Vz of the voltage regulator diode 13. time delay f1t
t is reached and the thyristor 9 is turned on.

At this time, the voltage across the generator coil 1e increases to vl.

Next, when the voltage reaches Vnz, the charging voltage waveform of the capacitor 12 becomes V.

Vc2 has a slope that is smaller than 1, and this voltage V
Time t2 required for cz to reach threshold voltage VZ
is shorter than tl, and the timing at which the thyristor 9 turns on is earlier than tl.

At this time, the voltage across the generator coil 1e increases to v2.

Here, the important thing is that when the voltage increases to Vnz, the period T
2 is shorter than T1.

Therefore, the period T1 . of each voltage Vnl Vnz. The relationship between T2 and thyristor 9 on-time tl, t2 is tl
, t2 T1 ° T2 If the constants of the charging circuit for the capacitor 12 are determined so that
The turn-on timing of the thyristor 9, that is, the conduction angle, is substantially constant.

In this way, the short-circuit current of the thyristor 9 becomes approximately constant regardless of the increase or decrease in the engine speed, and the generating coil 1
The armature reaction of e is stable regardless of the increase or decrease of the rotational speed, so that the a-direction output is not adversely affected and a stable ignition voltage can be obtained.

Incidentally, for the purpose of adjusting the influence of armature reaction, a similar effect can be obtained by connecting a resistor 15 in series with the thyristor 9 as shown in FIG.

Further, in this embodiment, a transistor is used to intermittent the a-direction output of the generator coil 1e, but a mechanical interrupter may also be used, and the generator coil 1e is an independent coil that does not also serve as the primary coil of the ignition coil. It is also possible to use

Further, the thyristor 9 may be replaced with another semiconductor switching element such as a transistor, and although the description has been made for a two-cycle engine, it is unlikely that the same effect will be obtained when applied to a four-cycle engine.

As described above, according to this invention, the resistor that suppresses the output of the other polarity that is not used for ignition of the generating coil is energized before the ignition timing, and after the ignition timing, the conduction angle of the semiconductor switching element is stabilized. Since the configuration is configured to bypass the generation of sparks before the ignition timing, the generation of unnecessary sparks before the ignition timing can be reliably prevented and the engine can be ignited appropriately. Since the large output of is not energized to the resistor, a significant practical effect can be obtained in that the heat generation of the resistor can be significantly reduced.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the magnet generator 1, Fig. 2 is an ignition circuit diagram showing a conventional device, Fig. 3 (■) is a voltage waveform diagram of the generating coil 1e, and Fig. 3 (■) is a diagram of the voltage waveform of the generating coil 1e. Current waveform diagram,
FIG. 4 is an ignition circuit diagram showing an embodiment of this invention, and FIG. 5 is an operational waveform diagram for explaining the operation of FIG. 4. In the figure, 1e is a power generation coil, 1f is a secondary coil, 2 and 3 are transistors, 4.5.6° 7.11, 14
．． 15 is a resistor, 8 and 10 are diodes, 13 is a constant voltage diode, and 9 is a thyristor. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A power generating coil that generates alternating current outputs of different magnitudes at least one cycle per revolution in synchronization with the rotation of the engine. Out of the above alternating current outputs, a unidirectional polarity output having a large output value is ignited by controlling it to the ignition timing of the above engine. A switching element that generates a high voltage in the secondary coil of the coil, a resistor that energizes and suppresses the output of the other polarity of the AC output before the ignition timing, and a resistor that is connected in parallel to this resistor when a phantom on state occurs. A semiconductor switching element that bypasses an output of the other polarity having a larger output value among the AC outputs that energize the resistor, and another resistor and a capacitor that are connected in series with each other and in parallel with the resistor; and a constant voltage diode connected to the connection point with the other resistor to determine the on timing of the semiconductor element, which determines the on timing of the semiconductor switching element regardless of the rotational speed of the engine, An internal combustion engine ignition system with a control circuit that remains on for an extended period of time.