JPS5916169B2 - igniter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an ignition device suitable for use in a cigarette lighter.

FIG. 1 is a circuit diagram showing an example of a conventional ignition device (cigarette lighter).

In the figure, a DC power source 1, a charging resistor 5, and a capacitor 6 are connected in series, and a series body in which a thyristor 4 and an ignition transformer 2 are connected in series is connected to the capacitor 6 in parallel.

10 is a well-known PUT oscillation circuit, and thyristor 4
The trigger circuit is composed of PUTll, a capacitor 12, and resistors 13 to 16.

3 is a discharge gap, and 4a is a resistor connected between the gate and cathode of the thyristor 4.

Next, the operation shown in FIG. 11 will be briefly explained.

A capacitor 6 is charged from a DC power supply 1 through a charging resistor 5.

On the other hand, the trigger circuit 10 of the thyristor 4 has a capacitor 6
It operates using the charging voltage as a power source.

That is, the capacitor 12 is charged through the charging resistor 13, and the potential on the resistor 13 side of the capacitor 12 is the same as that of the resistor 1.
When the potential becomes higher than the potential at the connection point of both resistors 14.15 determined by the division ratio of 4.15, PUT 11 turns on, and the capacitor 12 → PUT II → resistor 16 → gate of thyristor 4 → cathode of thyristor 4 → ignition The primary side of the transformer 2 is discharged in the loop of the capacitor 12, and the thyristor 4 is triggered.

When the thyristor 4 is turned on, the charge in the capacitor 6 is discharged in a loop of the capacitor 6 → the thyristor 4 → the primary side of the ignition transformer 2 → the capacitor 6.

The discharge energy of the capacitor 6 at this time is boosted by the ignition transformer 2 to generate a high voltage on the secondary side.

Therefore, sparks are generated in the discharge gap 3.

By the way, since a 9-12V manganese laminated battery is generally used as the DC power source 1, the voltage of the capacitor 6 will drop to 6-9V when consumption due to discharge is taken into consideration.

On the other hand, in a cigarette lighter or the like, in order to generate a stable spark in the discharge gap 3, it is necessary to generate a high voltage of about 8 Kv on the secondary side of the ignition transformer 2.

However, due to the voltage drop of thyristor 4, the voltage drop is 1 to 1.
．． Since a voltage equal to the voltage of 5V subtracted from the charging voltage of the capacitor 6 is applied to the primary side of the ignition transformer 2, the primary voltage of 5.0 to 7.5V must actually be boosted to 8KV. .

On the other hand, manufacturing transformers for cigarette lighters and the like is extremely difficult due to size limitations.

In other words, it is contradictory to improve the coupling between the primary and secondary windings and maintain insulation that can withstand high voltage, and to reduce the size.

By the way, conventionally, in ignition devices that use AC power as a power source, the above-mentioned problem can be solved by the Utility Model Publication No. 47
As shown in Publication No. 39128, No. 1. Second
There was a system in which a series connection of a diode and a capacitor was connected in parallel to an AC power supply, but this was just a conventional means of a voltage doubler generation circuit using an AC power supply for the ignition transformer, and this conventional circuit was, of course, , it could not be applied to ignition devices powered by DC power.

The present invention was made in order to eliminate the above-mentioned drawbacks of the conventional ignition device that uses a DC power source, and uses two capacitors and two switching elements so that they are connected in series during discharge. The purpose of the present invention is to supply an ignition transformer with a voltage that is approximately twice the power supply voltage in any number of songs, facilitate manufacturing of the ignition transformer, and provide an ignition device capable of obtaining large ignition energy.

FIG. 2 is a circuit diagram showing one embodiment of the present invention.

In the figure, a capacitor 61 and its charging resistor 51 are connected in series, and one end of the resistor 51 is connected to the positive terminal of the DC power source 1 and one end of the capacitor 61 is connected to the negative terminal of the DC power source 1.

Further, the capacitor 62 and its charging resistor 52 are connected in series, and one end of the capacitor 62 is connected to the positive terminal of the DC power source 1, and one end of the resistor 52 is connected to the negative terminal of the DC power source 1.

Furthermore, the thyristor 41 is connected between the connection point between the resistor 51 and the capacitor 61 and the connection point between the capacitor 62 and the resistor 52 so that the connection point side between the resistor 51 and the capacitor 61 becomes the anode, and the ignition transformer 2 By connecting the primary winding and the thyristor 42 in series, the thyristor 42
The anode of the ignition transformer 2 is connected to the positive electrode of the capacitor 62, and one end of the primary winding of the ignition transformer 2 is connected to one end of the resistor 62.

The other parts have exactly the same configuration as those in FIG. 1, and the same reference numerals are the same as those explained in FIG.

Note that 41a and 42a are resistors connected between the gates and cathodes of the thyristors 41 and 42, respectively, and the trigger circuit 1
16.17 out of 0 are the gate resistances of the thyristors 41 and 42, respectively.

Next, such a present fE operation will be explained.

Capacitors 61 and 62 are charging resistors 51 and 5, respectively.
It is charged through 2.

A pulse signal from the trigger circuit 10 is sent to the thyristor 41. '4
2, the thyristors 41 and 42 simultaneously turn on, the capacitors 61 and 62 are connected in series, and a voltage approximately twice the power supply voltage is applied to the primary winding of the ignition transformer 2.

That is, the charging voltage of the capacitors 61 and 62 is discharged in the loop of capacitor 61 → thyristor 41 → capacitor 62 → thyristor 42 → ignition transformer 2 → capacitor 61.

At this time, the voltages of the capacitors 61 and 62 are discharged through the resistor 51 and the thyristor 41 and the resistor 52 and the thyristor 41, respectively, but these loops have significantly higher impedance than the discharge loop through the ignition transformer 2 described above. The discharge is slight.

The triggering of thyristor 41.42 causes capacitor 61.
When the discharge of 62 occurs, a high voltage is generated in the secondary winding of the ignition transformer, and a spark is generated in the discharge gap 3.

When the discharge of the capacitor 61, 62 is completed, the thyristor 41, 42 immediately turns off because the circuit vibrates somewhat.

The thyristor 42 requires a thyristor with a short turn-off time.The 75ζ thyristor 41 does not necessarily require a thyristor with a short turn-off time.

If a large value charging resistor 51 and 52 is used, the current flowing in the loop of DC power supply 1 → charging resistor 51 → thyristor 41 → charging resistor 52 → DC power supply 1 will be smaller than the holding current of thyristor 41, transitions to the off state.

When the thyristors 41, 42 are turned off, the capacitors 61, 62 are charged again through the respective resistors 51, 52, waiting for a signal from the trigger circuit 10 and preparing for the next operation.

As can be understood from such an operation, unlike the conventional circuit shown in FIG.
Since the capacitors are connected in series, twice the voltage as in the case of FIG. 1 can be obtained, and twice the energy can be extracted from the ignition transformer 2.

Since the voltage applied to the primary winding of the ignition transformer 2 is thus doubled, the manufacture of the ignition transformer 2 of this embodiment is much easier than the manufacture of the ignition transformer 2 shown in FIG.

That is, as mentioned above, the circuit in Figure 1 has a voltage of 5 to 7.5V.
Since the voltage of In the above embodiment, the primary voltage doubles, and the step-up ratio also becomes 1/2, and the secondary winding Since the number of turns is reduced to 1/2, the design of the ignition transformer becomes easier.

3 only changes the order of series connection of the thyristor 42 and ignition transformer 2 of FIG. 2, and its operation is exactly the same as that of FIG. 2.

FIG. 4 shows a two-terminal switching element, for example a Shockley diode 4, in place of the thyristors 41 and 42 of FIG.
3.44, one two-terminal switching element 43 becomes conductive when the charging potential of the capacitor 61 reaches a predetermined level, and the other two-terminal switching element 44 becomes conductive when the charging potential of the capacitor 61 reaches a predetermined level. It is selected to be conductive when conductive, that is, when the combined charging potential of capacitors 61 and 62 reaches a predetermined level.

Note that 1d is a current limiting resistor for the two-terminal switching element 44 and the ignition transformer 2, and although it is omitted in the case of FIGS. 2 and 3, it is desirable to insert it when the internal resistance of the DC power source 1 is small. .

5 and 6 show that the connection position of the ignition transformer 2 in FIGS. 2 and 3 has been changed, and the connection positions of related parts have been slightly changed in accordance with this change.
Its operation is exactly the same as that in FIG.

In addition, in each of the above-mentioned embodiments, when trying to prevent unnecessary discharge of the force ζ capacitor 62 (not shown),
For example, in Fig. 2, capacitor 62 → resistor 51 →
In order to avoid discharge in the loop of the thyristor 41 and the capacitor 62, it is effective to insert a diode between the resistor 51 and the capacitor 62 so that the resistor 51 side becomes the anode.

As described above, according to the present invention, two charging circuits are provided, and the charges from each charging circuit are combined and supplied to the ignition transformer, so there is no need to increase the step-up ratio of the ignition transformer. This has the effect of making it easier to manufacture the ignition transformer and easily realizing an ignition device that is small and can extract a large amount of energy.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram showing an example of a conventional ignition device, Fig. 2 is a circuit diagram showing an embodiment of the present invention, and Figs. 3 to 6 are circuit diagrams showing other embodiments of the invention. It is. In the figure, 1 is a DC power supply, 2 is an ignition transformer, 3 is a discharge gap, 10 is a trigger circuit, 41 and 42 are thyristors (first and second switching elements), 43 and 44 are Shockley diodes (first .. second switching element), 51 and 52 are the first switching element. The charging resistors 61 and 62 of the second charging circuit are connected to the charging resistors 61 and 62 of the first charging circuit. This is the capacitor of the second charging circuit. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A first charging circuit consisting of a DC power supply, a series connection body of a charging resistor and a capacitor, connected between both ends of the DC power supply so that the charging resistance side becomes the positive terminal side of the DC power supply, and a charging resistor and a capacitor connected in series. a second charging circuit comprising a series connection body and connected between both ends of the DC power supply such that the charging resistor side thereof becomes the negative electrode side of the DC power supply; a charging resistor and a capacitor of the first and second charging circuits; an ignition transformer having a primary winding connected in parallel to the second charging circuit and having a discharge gap on the secondary side; When the charging potential of the capacitor of the first charging circuit, which is inserted and connected in series with the next winding, reaches a predetermined level, the first switching element becomes conductive, and both the capacitors of the first and second charging circuits are connected. An ignition device comprising a second switching element forming a discharge circuit.