JPH0241489Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to a discharge type ignition device for combustion equipment.
In particular, the present invention relates to an ignition device that has improved noise resistance and can be used with high reliability.

<Prior art> As an ignition device for combustion equipment that uses gas or other fuel, high voltage energy generated on the secondary side of a high voltage transformer is applied to a discharge electrode, and an ignition spark is generated at an ignition part (burner, etc.). There is.

For example, as disclosed in Japanese Unexamined Patent Publication No. 101421/1983, there is a circuit configuration as shown in Figure 3, which normally has a 4th circuit configuration.
It operates according to the operating waveform shown in the figure.

Switch 19 connected to commercial AC power supply 11
When the current is turned on, the capacitor 1 is turned on in half a cycle of the AC power supply through the current limiting resistor 12 and the rectifier 13.
4 is supplied with charging current.

The capacitor 14 constitutes a closed circuit together with the primary winding 16 of the high-voltage transformer and a discharge control rectifier 15 such as a Shockley diode or a cylindrical rectifier, and a reverse voltage blocking rectifier 17 is connected in parallel to the discharge control rectifier 15. has been done.

Therefore, the capacitor terminal voltage waveform Va during the half-cycle charging period of the AC power source becomes as shown in FIG. 4A, and gradually increases.

However, this voltage waveform Va becomes a predetermined voltage Eb,
That is, when the breakover voltage Eb of the discharge control rectifier 15 is reached, the discharge control rectifier 15
is turned on, the charge in the capacitor 14 is applied to the primary winding 16 of the high voltage transformer, an induced high voltage is generated on the secondary side, and during the discharge period 18, the voltage shown in FIG.
This produces a strong spark discharge, as shown in Figure 2, which helps ignite combustion equipment.

<Problems to be Solved by the Invention> The above-mentioned discharge type ignition device generally emits quite large radiant noise during discharge. This can cause noise in televisions, radios, and other wireless devices, and can cause soft errors in computer-related equipment.Recently, with the rapid spread of this type of ignition device, countermeasures have been developed. has become an urgent need.

The easiest way to meet these demands is to
These methods include reducing the number of discharges and using as little energy as possible, and these methods are now being adopted.

However, this has resulted in the disadvantage that the discharge ignition device itself becomes vulnerable to such noise, especially in special environments such as factories where there is a lot of external noise. This can be explained with reference to FIG.

As previously explained with reference to FIG. 4, under normal operation, the capacitor 14 is charged with a charge that eventually reaches the breakover voltage Eb of the discharge control rectifier 15 in half a cycle of the AC power supply. It should be done.

However, during the transient period, if spike noise Vn is superimposed as shown in FIG. A capacitor 14 is connected to the primary winding 16 of the high voltage transformer.
It happens that the charging energy of the battery is released.

Therefore, the resulting discharge voltage Vb is
As shown in FIG. 5B, there is a severe lack of energy, and the combustion equipment cannot be ignited normally.

Furthermore, even if the energy is sufficient for ignition, the ignition timing will be different from normal.

The present invention was developed in consideration of these points, and even if the radiated noise is reduced by lowering the discharge energy or reducing the number of discharges, it is a noise-resistant device that does not become vulnerable to external noise. The object is to provide a discharge ignition device with excellent characteristics.

<Means for Solving the Problems> In order to achieve the above object, the present invention proposes a discharge type ignition device having the following configuration.

A capacitor that is charged during a half cycle of the AC power supply, a primary winding of the high voltage transformer, and when the terminal voltage of the capacitor reaches a predetermined potential, the charge stored in the capacitor is transferred to the primary winding of the high voltage transformer. A discharge ignition device constitutes a closed circuit with a discharge control rectifier for discharging the discharge to the source, and a reverse voltage blocking rectifier is connected in parallel to the discharge control rectifier; in parallel with the discharge control rectifier, A discharge type ignition device characterized by connecting a capacitor for high frequency bypass and a resistor for leakage.

<Functions and Effects> According to the present invention, a capacitor is provided to bypass the external noise that causes the discharge control rectifier to malfunction, so that the capacitor is provided to bypass the external noise.
Even if the high frequency noise voltage Vn as described above with reference to FIG. 5A is applied, this component is bypassed via the bypass capacitor, so there is no risk of false triggering.

Also, when the power is turned off, the leakage resistor
Since it acts to quickly release the accumulated charge of the energy charging capacitor, it is possible to prevent accidents such as electric shock.

In this way, according to the present invention, it is possible to provide a discharge ignition device that has excellent noise resistance characteristics and is highly reliable in terms of ease of use.

<Embodiment> FIG. 1 shows a discharge type ignition device as a preferred embodiment of the present invention.
Parts with the same reference numerals indicate elements that are functionally or partially corresponding to those in the case of FIG. 3 shown as a conventional example, or elements that do not require particular modification, and parts with new numbers indicate elements related to the improvements of the present invention. It shows.

That is, in the present invention, the high frequency bypass capacitor 2 is connected in parallel to the discharge control rectifier 15.
0 and a leakage resistor 21 are provided.

Therefore, during the transition period in which the energy charging capacitor 14 is charged via the current limiting resistor 12 and the rectifier 13 during a half cycle of the AC power source 11 when the power switch 19 is turned on, the charging line is temporarily connected to the line shown in FIG. 5A. Even if the high-frequency spike noise Vn as shown is superimposed, it is bypassed via the high-frequency bypass capacitor 20, and therefore, as in the conventional example shown in FIGS. 5A and 5B, Therefore, the discharge control rectifier 15 will not be erroneously triggered. As shown in FIGS. 4A and 4B, the terminal voltage Va of the charging capacitor 14 always rises to the breakover voltage Eb, and normal operation can be maintained.

In addition, the leakage resistor 21 is connected to the power switch 19.
When the charging capacitor 14 is turned off, the residual charge stored in the charging capacitor 14 can be discharged more quickly than in the case where the charging capacitor 14 is not turned off, so that accidents such as electric shock can be prevented.

In the embodiment shown in FIG. 2, the positions of the discharge control rectifier 15 and the energy charging capacitor 14 are exchanged, and along with this, a reverse voltage blocking diode 17, a high frequency bypass capacitor 20, and a leakage resistor 21 are installed. Although it has been moved to a position parallel to the discharge control rectifier 15, its operation and function are exactly the same as those described with reference to FIG. In this embodiment, a cylindrical rectifier is used as the discharge control rectifier 15, but the rectifier 15 is not limited to this.

Note that even if the high-frequency bypass capacitor 20 includes a low resistance in series, it does not significantly affect the functions of the present invention.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of an embodiment of a discharge type ignition device according to the present invention, Fig. 2 is a schematic diagram of a second embodiment of the invention, and Fig. 3 is a typical example of a conventional discharge type ignition device. 4 is an explanatory diagram of the operation of the discharge ignition device of the present invention when the conventional discharge ignition device operates normally, and FIG. 5 is a diagram of the malfunction observed in the conventional discharge ignition device. It is. In the figure, 11 is an AC power supply, 14 is an energy charging capacitor, 15 is a discharge control rectifier, 16 is a high-voltage transformer primary winding, 17 is a reverse voltage blocking rectifier, 18 is a discharge gap, 19 is a power switch, 20
21 is a capacitor for high frequency bypass, and 21 is a resistor for leakage.

Claims (1)

[Claims for Utility Model Registration] A capacitor that is charged during a half cycle of an AC power source, a primary winding of a high-voltage transformer, and an electric charge that is charged in the capacitor when the terminal voltage of the capacitor reaches a predetermined potential. A discharge ignition device comprising: a discharge control rectifier for discharging the voltage to the primary winding of the high-voltage transformer; and a discharge control rectifier connected in parallel to the discharge control rectifier; A discharge type ignition device characterized in that a capacitor for high frequency bypass and a resistor for leakage are connected in parallel with a rectifier for discharge control.