JPH01298688A - Ignitor for high-voltage electric-discharge lamp - Google Patents

Abstract

PURPOSE:To enable the instantaneous restart just after putting out without shortening the lives of a discharge gap and a high-voltage electric-discharge lamp by providing also a discharge circuit passing through an impedance element and the lamp. CONSTITUTION:In the initial starting easy to light just after inputting a power source, the charge discharged by a capacitor C1 of a charging circuit CH is supplied to the provided discharge circuit of an impedance Z and a high-voltage electric-discharge lamp LA, and the lamp LA is started without obtaining an excessive stress by a pulse voltage which is higher than the low discharge starting voltage in the initial starting and lower than the restarting voltage. On the other hand, a discharge current is run into a two-terminal discharge gap G by discharging a high charged charge of the capacitor C1, and the lamp LA after putting out is restarted by the high pulse voltage. Thus, the high- voltage electric-discharge lamp can be instantaneously restarted after putting out without reducing the lamp life and the life of the two-terminal discharge gap which discharges only when required.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to an igniter for a high-pressure discharge lamp that applies a high-voltage pulse for starting to the high-pressure discharge lamp to light the high-pressure discharge lamp. The present invention relates to an igniter for a high-pressure discharge lamp that can instantaneously restart a high-pressure discharge lamp.

[Conventional technology]

Conventional discharge lamp lighting devices for general high-pressure discharge lamps are
As shown in Figure 4, for example, an electric power source consisting of a commercial AC power source
(DC power supply, high frequency power supply, and square wave power supply are also possible) A high pressure discharge lamp 3 is connected to l via an inductive ballast 2, and an igniter 4 for the high pressure discharge lamp that generates a high voltage pulse for starting is installed. The high pressure discharge lamp 3 is started and lit by applying a high voltage pulse for starting to the high pressure discharge lamp 3 from the discharge lamp igniter 4.

Specifically, as shown in FIG. 5, the above-mentioned igniter 4 for a high-pressure discharge lamp supplies power from both ends of a bypass capacitor 9 to terminals a and b of a DC high voltage generating circuit 5 such as a Kotscroft circuit, and the DC A charging circuit 6 consisting of a capacitor 6a and a resistor 6b is connected to terminals c and d of the high voltage generating circuit 5, and the primary winding n of the step-up transformer 8 is connected to the output terminal of the charging circuit 6.
A two-terminal discharge gap 7 is connected through the power source 1, and the secondary winding n2 of the step-up transformer 8 is inserted in series in the current-carrying path from the power source 1 to the high-pressure discharge lamp 3, bypassing the inductive ballast 2 and increasing the high voltage. Secondary winding n of discharge lamp 3 and step-up transformer 8
A bypass capacitor 9 is connected to form a closed loop with the series circuit of A (disclosed as a conventional example in Japanese Patent Application No. 62-326328).

In this high-pressure discharge lamp igniter 4, before the high-pressure discharge lamp 3 is lit, the voltage across the bypass capacitor 9 is approximately the power supply voltage, and this voltage is applied between the terminals a and b of the DC high voltage generation circuit 5. is added between terminals c and d.
As shown in the figure (al), a DC high voltage ■ゎ□ (〉discharge starting voltage VG) is generated.

Then, the capacitor 6a of the charging circuit 6 is charged by the output current of the DC high voltage generating circuit 5 through the resistor 6b, and the voltage V across the capacitor 6a of the charging circuit 6 gradually increases as shown in FIG. 6(a). rise to Above capacitor 6
The voltage across a is applied to the two-terminal discharge gap 7, and its value is the discharge starting voltage Vc of the two-terminal discharge gap 7.
, the two-terminal discharge gap 7 is discharged, the charge in the capacitor 6a is rapidly discharged through the primary winding n1 of the step-up transformer 8, and the secondary winding n2 of the step-up transformer 8 is discharged as shown in the sixth opening). A high voltage pulse V, is generated and applied to the high pressure discharge lamp 3 through the bypass capacitor 4. Thereafter, the above operation is repeated, and the high pressure discharge lamp 3 is started and lit at an appropriate time.

When the high pressure discharge lamp 3 lights up, the DC high voltage generation circuit 5
The voltage applied between terminals a and b of the high pressure discharge lamp 3 is
The lamp voltage is almost equal to that of the lamp voltage, which is considerably lower than the power supply voltage.
As shown in Figure 6 fa), the DC high voltage generated between
cdZ (<discharge starting voltage Vs), and even if the capacitor 6a of the charging circuit 6 is charged with the DC high voltage Ve4Z, the voltage VC across the capacitor 6a' becomes the discharging starting voltage ■
, will no longer exceed. Therefore, the two-terminal discharge gap 7
The discharge of the voltage stops, and the generation of the high voltage pulse VP stops.

In this case, the voltage required to start the high-pressure discharge lamp is several kilovolts at the time of initial starting, but several tens of kilovolts are required when it is desired to restart the lamp instantly immediately after the lamp has been turned off.

For this reason, in the above-mentioned igniter for a high-pressure discharge lamp, which is intended to instantly restart the high-pressure discharge lamp immediately after extinguishing, the circuit is designed to generate a high-voltage pulse of, for example, several tens of kilovolts.

[Problem to be solved by the invention]

As mentioned above, when a high-pressure discharge lamp igniter whose circuit is designed to generate high-voltage pulses of several tens of kilovolts is used to start a high-pressure discharge lamp, a wave of high-voltage pulses is applied to the high-pressure discharge lamp during initial startup. The high price becomes excessive,
There is a problem in that excessive stress is applied to the high-pressure discharge lamp, and the life of the high-pressure discharge lamp is extremely shortened.

Furthermore, since the two-terminal discharge gap 7 performs discharge to start the high-pressure discharge lamp 3 both at the time of initial startup and at the time of restart, there is a problem that the life of the two-terminal discharge gap 7 is short.

The purpose of this invention is to enable a high-pressure discharge lamp to be instantly restarted immediately after extinguishing without shortening the life of the high-pressure discharge lamp, and to extend the life of a two-terminal discharge gap. The purpose is to provide an igniter.

[Means to solve the problem]

The igniter for a high pressure discharge lamp of the present invention applies a high voltage pulse for starting to a high pressure discharge lamp connected to a power source via an inductive ballast.

This igniter for high-pressure discharge lamps connects a charging circuit to the output end of a DC high voltage generation circuit, connects a two-terminal discharge gap to the output end of the charging circuit via the primary winding of a step-up transformer, and connects it to the power supply. The secondary winding of the step-up transformer is inserted in series in the power path to the high-pressure discharge lamp, bypassing the inductive ballast, and forming a closed loop with the series circuit of the secondary winding of the high-pressure discharge lamp and the step-up transformer. In an igniter for a high-pressure discharge lamp connected to a bypass capacitor, a discharge path for the charge in the charging circuit passing through an impedance element, a high-pressure discharge lamp, and a step-up transformer is provided, and the discharge starting voltage of the two-terminal discharge gap is adjusted to the initial stage of the high-pressure discharge lamp. It is characterized in that it is set higher than the discharge starting voltage at the time of starting and lower than the discharge starting voltage at the time of restarting.

[For production]

In the configuration of this invention, the charging circuit is charged with the output current of the DC high voltage generating circuit, and the charging voltage of this charging circuit is applied to the two-terminal discharge gap and the high-pressure discharge lamp.

The charging voltage of this charging circuit increases as charging progresses,
When the lower of either the two-terminal discharge gap or the discharge start voltage of the high-pressure discharge lamp is exceeded, the charge in the charging circuit is rapidly discharged through either the two-terminal discharge gap or the high-pressure discharge lamp, and the above operation is repeated thereafter. It will be.

At the initial startup of the high-pressure discharge lamp, the discharge starting voltage of the high-pressure discharge lamp is lower than the discharge starting voltage of the two-terminal discharge gap, so the discharge lamp slightly discharges and the charge in the charging circuit is transferred between the impedance element and the high-pressure discharge lamp. It is released along a path that passes through the step-up transformer, and by repeating this operation, the high-pressure discharge lamp is started and lit. At this time, since the charging voltage of the charging circuit does not reach the discharge starting voltage of the two-terminal discharge gap, the two-terminal discharge gap does not discharge.

On the other hand, when restarting a high-pressure discharge lamp, the discharge starting voltage of the high-pressure discharge lamp is higher than the discharge starting voltage of the two-terminal discharge gap, so the two-terminal discharge gap discharges through the primary winding of the step-up transformer and the charging circuit. The charging charge is released in its path through the step-up transformer's primary winding, which generates a high-voltage pulse in the step-up transformer's secondary winding, which is applied to the high-pressure discharge lamp through the bypass capacitor, resulting in its operation. By repeating these steps, the high-pressure discharge lamp starts and lights up.

In this igniter for a high-pressure discharge lamp, at the initial start-up, the high-pressure discharge lamp itself is slightly discharged to start the high-pressure discharge lamp and reach lighting, so the peak value of the high-voltage pulse applied to the high-pressure discharge lamp The stress applied to the electric bridge of the high-pressure discharge lamp during initial startup can be reduced, and the life of the high-pressure discharge lamp will not be shortened. Furthermore, since the two-terminal discharge gap does not discharge during initial startup, the life of the two-terminal discharge gap can be extended.

Moreover, when restarting, the charge in the charging circuit is rapidly discharged through the primary winding of the step-up transformer by discharging the two-terminal discharge gap, and the induced voltage in the secondary winding of the step-up transformer is applied to the high-pressure discharge lamp. The peak value of the high-voltage pulse applied to the high-pressure discharge lamp is large, and the high-pressure discharge lamp can be instantly restarted immediately after being turned off.

〔Example〕

A first embodiment of this invention will be described based on FIGS. 1 and 3. That is, as shown in FIG. 1, this igniter for a high-pressure discharge lamp is powered by, for example, a commercial AC power source (DC power source, high frequency power source, etc.).

A rectangular wave power supply is also possible) ① A high voltage pulse for starting is applied to the high pressure discharge lamp LA connected to 8 via the inductive ballast BA.

Specifically, this igniter for high pressure discharge lamps is
Power is supplied from the AC power supply VS+ to a DC high voltage generation circuit EE such as a Kotsukucroft circuit, and a charging circuit CH consisting of a capacitor CI and a resistor R3 is connected to the output terminal of this DC high voltage generation circuit EE. A two-terminal discharge gap G is connected through the primary winding n1 of the step-up transformer TR, and the secondary winding n8 of the step-up transformer TR is inserted in series in the current-carrying path from the power supply VSZ to the high-pressure discharge lamp LA to stabilize the inductive property. A bypass capacitor C8 is connected so as to form a closed loop with the series circuit of the high-pressure discharge lamp LA and the secondary winding n= of the step-up transformer TR, bypassing the transformer BA.

In addition, a discharge path for the charge of the charging circuit CH passing through the impedance element Z, the high pressure discharge lamp LA, and the primary winding n1 of the step-up transformer TR is provided, and the discharge starting voltage V of the two-terminal discharge gap G is set to the high pressure discharge lamp. The discharge starting voltage VLC at the initial start of LA is set higher than the discharge starting voltage VL at the time of restarting, and lower than the discharge starting voltage VL at the restart.

The above impedance element Z is inserted in order to suppress or prevent current from flowing from the main circuit that supplies lamp current to the high pressure discharge lamp LA to the high pressure discharge lamp igniter. is a series circuit consisting of a single resistor R2 as shown in Figure 3 fat, a resistor R3 as shown in Figure 3 Tbl, and a diode D, Figure 3 fcl
Zener diode ZD like, and diode D
Two series circuits are given as an example.

In this high-pressure discharge lamp igniter, a charging circuit CH is charged with the output current of the DC high-voltage generating circuit EE, and the charging voltage of the charging circuit CH is applied to the two-terminal discharge gap G and the high-pressure discharge lamp LA.

The charging voltage of this charging circuit CH increases as charging progresses, and when it exceeds whichever is lower of the two-terminal discharge gap G or the discharge start voltage of the high-pressure discharge lamp LA, the charging voltage of the charging circuit CH increases.
The charge H is rapidly discharged through either the two-terminal discharge gap G or the high-pressure discharge lamp LA, and the above operation is repeated thereafter.

When the high-pressure discharge lamp LA is initially started, the discharge starting voltage VtC0 of the high-pressure discharge lamp is lower than the discharge starting voltage vG of the two-terminal discharge gap G, so the high-pressure discharge lamp LA is slightly discharged and the charge in the charging circuit CH becomes impedance. A high voltage pulse is emitted along a path passing through the element Z, the high pressure discharge lamp LA, and the primary winding n1 of the step-up transformer TR, thereby inducing a high voltage pulse in the secondary winding n2 of the step-up transformer TR, which is applied to the high-pressure discharge lamp LA, By repeating this operation, the high pressure discharge lamp LA is started and lit.

At this time, the charging voltage of the charging circuit CH is the two-terminal discharge gear,
Discharge starting voltage of BU G■. Therefore, the two-terminal discharge gap G does not discharge.

On the other hand, when restarting the high-pressure discharge lamp LA, the discharge starting voltage V of the two-terminal discharge gap G is higher than that of the high-pressure discharge lamp LA.
Since the discharge starting voltage VLH is higher, the two-terminal discharge gap G discharges through the primary winding n1 of the step-up transformer TR, and the charge in the charging circuit CH is discharged along the path passing through the primary winding &jln+ of the step-up transformer TR. This generates a high voltage pulse in the secondary winding n2 of the step-up transformer TR,
This high voltage pulse is applied to the high pressure discharge lamp LA through the bypass capacitor C2, and by repeating this operation, the high pressure discharge lamp LA starts and lights up.

Note that when the high-pressure discharge lamp LA lights up, the AC power supply VS+ is cut off by some means.

In this igniter for a high-pressure discharge lamp, at the initial start-up, the high-pressure discharge lamp LA is started by slightly discharging the high-pressure discharge lamp LA itself, so that the high-pressure discharge lamp LA reaches lighting.
The peak value of the high voltage pulse applied to the high pressure discharge lamp LA is small, and the stress applied to the electrodes of the high pressure discharge lamp LA during initial startup can be reduced.
A's lifespan will not be shortened. Furthermore, since the two-terminal discharge gap G does not discharge during initial startup, the life of the two-terminal discharge gap G can be extended.

Furthermore, upon restart, the two-terminal discharge gap G is rapidly discharged through the primary winding n1 of the step-up transformer TR, and the secondary winding n! is applied to the high-pressure discharge lamp LA, the peak value of the high-voltage pulse applied to the high-pressure discharge lamp LA is large (and the high-pressure discharge lamp LA can be instantaneously restarted immediately after being turned off.

A second embodiment of the invention will be described based on FIG.

This igniter for high-pressure discharge lamps, as shown in Figure 2,
Instead of the path passing through the primary winding n1 of the step-up transformer TR,
A discharge path for the charge of the charging circuit CH passing through the impedance element Z, the high-pressure discharge lamp LA, and the secondary winding n8 of the step-up transformer TR is provided, and the discharge starting voltage of the two-terminal discharge gap G is set. is higher than the discharge starting voltage VtC at the time of initial starting of the high pressure discharge lamp LA and the discharge starting voltage VL at the time of restarting.
It is set lower than N.

In the igniter for a high-pressure discharge lamp of this embodiment, although the step-up effect by the step-up transformer TR cannot be obtained, the high-pressure discharge lamp LA is easy to start at the initial start.
There is no particular inconvenience.

The effects of this embodiment are similar to those of the first embodiment.

〔Effect of the invention〕

According to the igniter for a high-pressure discharge lamp of the present invention, a discharge path for the charge of the charging circuit passing through the impedance element, the high-pressure discharge lamp, and the step-up transformer is provided, and the discharge starting voltage of the two-terminal discharge gap is set at the initial start-up of the high-pressure discharge lamp. Since the discharge starting voltage is set higher than the discharge starting voltage during initial startup and lower than the discharge starting voltage during restart, the peak value of the high voltage pulse applied to the high-pressure discharge lamp is small, reducing stress on the electrodes of the high-pressure discharge lamp during initial startup. can be used without shortening the life of the high-pressure discharge lamp. Further, at the initial startup, the two-terminal discharge gap does not discharge, and the life of the two-terminal discharge gap can be extended.

Moreover, when restarting, the peak value of the high voltage pulse applied to the high-pressure discharge lamp is large, and the high-pressure discharge lamp can be instantly restarted immediately after extinguishing.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing the configuration of a first embodiment of the present invention;
FIG. 2 is a circuit diagram showing the configuration of a second embodiment of the present invention;
FIG. 3 is a circuit diagram showing a specific example of the main parts of the circuits shown in FIGS. 1 and 2, FIG. 4 is a circuit diagram showing the structure of a conventional general discharge lamp lighting device, and FIG. 4 is a circuit diagram showing a specific configuration of an igniter for a high pressure discharge lamp used in the circuit of FIG. 4, and FIG. 6 is a time chart of each part of the circuit of FIG. 5. EE...DC high voltage generation circuit, CH...charging circuit,
LA... High pressure discharge lamp, ■, □... Power supply, BA...
...Inductive ballast, C! ...Bypass capacitor, T
R...Step-up transformer, G...2-terminal discharge gap,
Z... Impedance element k →. Figure 2 (a) a b Figure 3 Figure 5 Figure 6 Procedural amendment (self-initiated August 21, 1999 1, Hanyu's No. 063 patent application No. 130765 2, title of the invention: High-pressure discharge lamp igniter 3, relationship with the case of the person making the amendment Patent applicant 5, date of amendment order (1) On page 4, line 14 of the specification, "bypass capacitor 4" is corrected to "bypass capacitor 9" .

Claims (1)

[Scope of Claim] An igniter for a high-pressure discharge lamp that applies a high-voltage pulse for starting to a high-pressure discharge lamp connected to a power source via an inductive ballast, the igniter comprising a charging circuit at the output end of a DC high-voltage generating circuit. is connected to the output terminal of the charging circuit through the primary winding of the step-up transformer.
A terminal discharge gap is connected, and a secondary winding of the step-up transformer is inserted in series in a current-carrying path from the power source to the high-pressure discharge lamp, bypassing the inductive ballast to connect the high-pressure discharge lamp and the step-up transformer. In an igniter for a high-pressure discharge lamp in which a bypass capacitor is connected to form a closed loop with a series circuit of a secondary winding, a discharge path of the charge in the charging circuit passes through an impedance element, the high-pressure discharge lamp, and the step-up transformer. An igniter for a high-pressure discharge lamp, characterized in that the discharge starting voltage of the two-terminal discharge gap is set higher than the discharge starting voltage at the time of initial starting of the high-pressure discharge lamp and lower than the discharge starting voltage at the time of restarting the high-pressure discharge lamp. .