JPS5914297A - Method of firing and driving high voltage discharge lamp - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a high-pressure discharge lamp lighting and driving method that eliminates acoustic instability during high-frequency lighting of a high-pressure discharge lamp and enables stable lighting and driving.

[Technical background of the invention]

BACKGROUND ART Due to reasons such as reduction in ballast power consumption and reduction in size and weight, attention has been paid to driving and lighting high-pressure discharge lamps using a high-frequency power source of 1K11z to 100KHz. 1st
The figure shows a schematic configuration of this type of high-frequency lighting drive device, in which numeral 1 indicates a high-frequency power supply device, and 2 indicates a commercial discharge pipe driven by the power supply device 1 for lighting. The above-mentioned high-frequency power supply bag [1 inputs the rectified and smoothed voltage of the commercial power supply, and through the alternating operation of the transistors Qi = Q2, it energizes the primary winding of the transformer T, and the high-frequency power is applied to the secondary winding of the transformer T. This is a push-pull inverter that obtains a secondary voltage and is well known in the past. However,
IKHz~1 generated by this high frequency power supply device 1
A high frequency voltage of 0.00 KHz is applied to both opposing electrodes of the high pressure discharge lamp 2, thereby driving the high pressure discharge lamp 2 to light. FIG. 2 shows the waveform of the lamp drive voltage VL applied to the high-pressure discharge lamp 2. In FIG. In particular, the push-pull type high-frequency power supply device 1 described above is highly desirable as a high-frequency lighting drive source for the high-pressure discharge lamp 2 because of its high oscillation efficiency.

[Problems of Background Art] However, when the high-pressure discharge lamp 2 is lit and driven in this manner, the high-pressure discharge lamp 2 has a drawback that an acoustic instability phenomenon often occurs. That is, as shown in FIG. 3, the discharge path 3 bends in various ways inside the bright tube 2 of the high-pressure discharge lamp and causes so-called "snaking" in which it rotates in the radial direction.

This phenomenon occurs because the sound waves defined by the shape and dimensions of the arc tube 2 and the composition of the filling material resonate with the high-frequency voltage applied to the arc tube 9.The shape of the arc tube is complex and there are many types of filling materials. It has a relatively large number of resonance modes. Furthermore, even the same lamp has various resonance modes from the starting ridge to stable lighting.

Therefore, the brightness of the high pressure discharge lamp 2 is spatial.

In addition to significant variations over time, destruction may occur due to local heating of the arc tube due to uneven discharge paths, or even if it does not lead to destruction, it may disappear or the temperature of other parts of the arc tube may decrease due to encapsulation. Insufficient evaporation of the substance caused deviations in luminescent color, and improvement of this problem was strongly desired. Particularly, such a phenomenon was remarkable when the high frequency power supply device 1 was a push-pull inverter shown in FIG. This is because, as will be described later, the waveforms of the push-pull inverter's coupling and output pressure are close to sinusoidal waves with positive and negative symmetry.

[Purpose of the invention]

The present invention has been made in consideration of the above circumstances, and its purpose is to provide a high-voltage discharge lamp capable of suppressing the sonic inconstancy of a high-pressure discharge lamp when it is driven using a high-frequency power source. An object of the present invention is to provide a discharge lamp lighting driving method.

[Outline of the invention]

The present invention applies a voltage when driving a high-pressure discharge lamp to light, shifts the acoustic resonance mode that should occur in the positive half-wave and the acoustic resonance mode that should occur in the negative half-wave, and uses the interference of the above two modes to generate a single signal. The purpose is to stabilize the discharge by destroying the constant mode.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 4 and 5.

Figure 4 is a schematic configuration diagram of a high-pressure discharge lamp lighting device that superimposes a pulse voltage on a high-frequency output voltage to generate an asymmetrical waveform and applies this to a high-pressure discharge lamp to light the high-pressure discharge lamp. 1 is a push-pull type high frequency power supply device, and 2 is a high pressure discharge lamp energized by the island frequency illumination device 1.

between the high frequency power supply circuit 1 and the high pressure discharge lamp 20.

I KHz~100K outputted by the high frequency power supply circuit 1
A high frequency output voltage of Hz having a voltage waveform as shown in FIG. The pulse transformer 4 has a pulse voltage (as shown in FIG. 5) at its secondary winding (
The pulse voltage from the pulse generator 5 (in the figure) is superimposed on the frequency output voltage (Figure 5(a)) that generates a pulse width of 3 u sec), and a positive voltage as shown in Figure 5(C) is generated. A city where the half wave and negative half wave are asymmetric.

A pressure waveform is being generated. Therefore, this asymmetrical voltage waveform is applied to the electrodes of the high-pressure discharge tube 2. When such a voltage waveform is applied, the acoustic instability that occurs when the Norse voltage is not superimposed is eliminated. According to the inventors' experiments, the high-pressure discharge lamp mentioned above is a metalnoride lamp.

Arc tube dimensions are inner diameter 10mm, electrode spacing 15111+1 *inner volume 1.4cc, 8cI3 and NaI filling amounts are 1.7Q and 83cm respectively, mercury filling amount is 2011tg,
The acoustic instability that occurred when the lamp input was set to too much for a case where the amount of Ar gas filled in was 39 tons was found to be 1.8-1.8 - This creates a cell that stabilizes the discharge, and this effect becomes noticeable when the difference in peak value is 5- or more. In particular, when the high frequency power supply is a push-pull inverter, the high frequency output voltage is close to a sine wave, so the acoustic resonance phenomenon becomes noticeable.

By superimposing pulses, this acoustic resonance phenomenon can be reliably prevented.

In the improved embodiment, the Norculus voltage superimposed on the high-frequency output voltage is superimposed at the peak of the high-frequency output voltage,
The present invention is not limited to this, but it is also possible to superimpose "C" when the phase shifts to a positive half cycle or when the high frequency output voltage is increasing.

Therefore, the degree of asymmetry of the TIY pressure applied to the fluid pressure discharge rung is not determined only by the peak values of the positive half-wave and the negative half-wave.

It goes without saying that the degree of asymmetry can be determined by taking into account the high voltage number II (the operating conditions of lamp 2, the life span that ensures stable operation, etc.).It also depends on the type of high pressure discharge lamp. Therefore, the degree of asymmetry described above can be determined in order to set the optimum operating state.
It is not necessary to apply the pressure periodically every cycle. Furthermore, pulse voltage is applied to each positive half wave and negative half wave! It may be 1 tatami I~. However, even in this case, it goes without saying that asymmetry can be sufficiently ensured by, for example, changing the phase of superimposing the pulse voltages. Fourthly, the high frequency power supply device 1 and the pulse voltage superimposition means are also described.

The circuit system etc. are not particularly limited.

As another example, FIG. 7 shows a case where the high frequency drive voltage is clipped to an asymmetrical waveform by the clip circuit 6 shown in the circuit configuration of FIG. Voltage was detected.

Of the three embodiments described above, the method of superimposing a pulse voltage on the high-frequency output voltage of the first embodiment and the method of superimposing the high-frequency output voltage of the second embodiment are based on simply changing the voltage waveform applied to the high-pressure discharge lamp. Since it is not only made asymmetrical but also distorted, the effect is greater than that of the third embodiment in which a DC voltage is superimposed on the high frequency voltage.

・ [Effects of the Invention] As detailed above, according to the present invention, by applying a high frequency wave with an asymmetrical positive half-wave and negative half-wave to a high-pressure discharge lamp, the shape of the arc tube of the high-pressure discharge lamp can be changed. Acoustic instability can always be eliminated regardless of the enclosed material or the time after lighting.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of a conventional high-pressure discharge lamp lighting device, FIG. 2 is a diagram showing the high-pressure discharge lamp driving voltage in the conventional device, and FIG. 3 is a diagram schematically showing acoustic instability. FIG. 4 is a schematic configuration diagram of a high-pressure discharge lamp lighting device constructed by adopting an embodiment method of the present invention, and FIG. 5(a)
~(C) are diagrams showing the high-frequency drive voltage, pulse voltage, and their combined voltage waveforms, and Figures 6 and 7 are circuits of a high-pressure discharge one-lamp lighting device configured by adopting the method of clipping the drive voltage, respectively. FIG. 2 is a diagram showing a configuration diagram and its high-frequency drive voltage. FIG. 8 and FIG. 9 are diagrams showing a circuit configuration of a high-pressure discharge lamp lighting device constructed by adopting a method of superimposing DC voltages to make the device asymmetrical, and a diagram showing its high-frequency driving voltage, respectively. l...Push-pull type high frequency power supply device, 2...High pressure discharge lamp (luminous tube), 3...Discharge path, 4...
Pulse transformer, 5... pulse generator, 6... clip circuit, 7... DC superimposition circuit. Agent Patent Attorney Kensuke Chika (and 1 other person) Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 Figure 7 Figure 9 Figure 6 Figure 8

Claims (5)

[Claims] (1) When driving a high-pressure discharge lamp using a high-frequency power supply, the waveforms of the positive half-wave and negative half-wave of the output voltage of the high-frequency power supply are made asymmetrical, and this asymmetrical driving voltage is applied to the high-pressure discharge lamp. A method for driving a high-pressure discharge lamp and a high-pressure discharge lamp, characterized in that the voltage is applied to the electrodes of the discharge lamp. (2) The high-pressure discharge lamp lighting and driving method according to claim 11, wherein the high-frequency power supply device is a push-pull inverter. (3) The driving voltage of the asymmetrical waveform applied to the high-pressure discharge lamp is obtained by superimposing a pulse voltage on the output voltage of a high-frequency power supply device.
The high-pressure discharge lamp lighting driving method as described in item (2) or item (2). (4) Claims (1) or (2), characterized in that the asymmetrical waveform driving voltage applied to the high-pressure discharge lamp is obtained by clipping the output voltage of a high-frequency power supply device. How to drive a high-pressure discharge lamp. (5) The asymmetrical wave applied to a high-pressure discharge lamp or the high-pressure discharge lamp lighting driving method according to item (2).