JPS601794A - Device for firing 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 an improvement in a discharge lamp lighting device that improves the color rendering of emitted light from a high-pressure metal vapor discharge lamp such as a metal halide lamp.

[Technical background of the invention and its problems]

High-pressure metal vapor discharge lamps such as metal halide lamps and high-pressure mercury lamps generally have an arc tube equipped with a discharge electrode built into a jacket tube. When the arc is lit so that the arc between the discharge electrodes of the arc tube is horizontal, the arc curves upward due to buoyancy due to imbalance in temperature distribution within the arc tube, and gas convection within the arc tube. As the arc curves upward, the temperature of the upper tube wall of the arc tube increases.

The temperature of the lower tube wall becomes relatively low, and as a result, metals sealed in the arc tube, such as metal halides, which have precipitated at the bottom of the arc tube, are not sufficiently evaporated and the color of the emitted light of the metal is reduced. Therefore, there was a problem that the color temperature of the emitted light was high and the Gali color rendering properties were poor.

[Purpose of the invention]

The present invention has been made in view of the above problems.

An object of the present invention is to provide an improved discharge lamp lighting device capable of preventing deterioration in color rendering properties due to arc curvature of a horizontally lit high-pressure metal vapor discharge lamp and emitting radiation having a predetermined color temperature.

[Summary of the invention j The present invention is to apply an alternating magnetic field with a frequency of 200 Hz or less generated by a magnetic field generation mechanism to the arc of a horizontally lit high-pressure metal vapor discharge lamp to expand the arc and improve color rendering. This is a discharge lamp lighting device characterized by:

[Embodiments of the invention]

The details of the invention will be explained with reference to the accompanying drawings.

FIG. 1 is a circuit configuration diagram of one embodiment of the discharge lamp device of the present invention, and FIG. 2 is a circuit diagram of another embodiment.

Horizontally lit. For example, a high-pressure metal vapor discharge lamp q) such as a metal halide lamp has an arc tube (3) inside the outer tube (2).
) is built-in. Discharge electrodes at both ends (4), (4)
In the arc tube (3) provided with this, metal halides such as indium iodide and thallium iodide, and mercury are sealed together with an easily dischargeable electric material. The lead wire (5) led out from the metal vapor discharge lamp (1), (5) is the lighting device (6)
The lighting device (6) is connected to an AC power source (7). A voltage is applied from the AC power supply (7) and an arc (8) is generated between the discharge electrodes (4L (4)).

The AC power source (7) has a lighting device (6) as shown in the first diagram.
) is connected in parallel with the coil αυ of the electromagnet OI'11 of the magnetic field generating mechanism (9).

Therefore, when an alternating current voltage is applied to the high pressure metal vapor discharge lamp (1) from the alternating current power source (7), an alternating current flows through the coil αυ of the electromagnet α and an alternating magnetic field is generated by the magnetic field generating mechanism (9). The alternating magnetic field acts on the arc (8) of the arc tube (3) of the high pressure metal vapor discharge lamp (1).

Vibrate the arc (8).

The vibration of the arc (8) causes the arc tube (3) to move downward α.
The metal precipitated in 2 is heated and evaporated. Conventional high-pressure metal vapor discharge lamps in which the above-mentioned metals were precipitated emitted strong blue radiation mainly due to mercury, but in the high-pressure metal vapor discharge lamp used in the present invention, the lower Q2 of the arc tube (3) is heated. Therefore, it was possible to emit synchrotron radiation with a predetermined high color rendering property.

The arc of the arc tube is expanded by the alternating magnetic field, and the charged particles in the discharge space of the arc tube to which the magnetic field is applied are proportional to the strength of the magnetic field, which changes over a period of 9 hours, as shown by the arrows in Figure 3. This seems to be due to the rotating motion of the charged particles, and the swirling motion of the charged particles depends on the frequency of the alternating magnetic field, and if the frequency becomes too high, the expansion of the arc becomes small. According to experiments conducted by the present inventors, it has been found that unless the frequency is 200 Hz or less, the temperature below the arc tube will rise sufficiently. Therefore, an alternating magnetic field with a frequency higher than 200 squares showed an effective effect as long as it was sufficient.

This is another embodiment of the discharge lamp lighting device of the present invention in which a coil aυ of an electromagnet α1 is connected, and even with such a circuit, if the frequency of the alternating magnetic field is 200 Hz or less, the effect exactly the same as that shown in Fig. 1 can be obtained. Indicated.

Note that when the arc is expanded by the alternating magnetic field, the tube voltage of the arc tube increases, but it is easy to design the lamp by increasing the impedance of the ballast in anticipation of this increase. therefore.

There is no drawback that the lamp life is shortened by shading the alternating magnetic field.

High-pressure metal vapor discharge lamps are metal halide lamps.According to experiments, the direction of the magnetic field generated by the magnetic field generation mechanism does not seem to have any particular effect on the expansion of the arc, for example, in a gap that is about the length of the arc of a metal halide lamp. .

A discharge lamp lighting device characterized by comprising a magnetic field generation mechanism that applies an alternating magnetic field with a frequency of 200 Hz or less to the arc of the high-pressure metal vapor discharge lamp to expand the arc, the discharge lamp lighting device comprising: When a high-pressure metal vapor discharge lamp such as a lamp is lit horizontally, the enclosed metal is sufficiently evaporated by the swirling motion caused by the alternating magnetic field of the arc of the arc tube, making it possible to emit light with a desired color rendering property. It has excellent effects.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of one embodiment of the discharge lamp lighting device of the present invention, Fig. 2 is a circuit diagram of another embodiment of the invention, and Fig. 3 is a high-pressure metal shown in Figs. 1 and 2. FIG. 2 is a schematic diagram showing the direction of swirling motion of charged particles in a discharge space when looking from the side of a steam discharge lamp. y... High pressure metal vapor discharge lamp 3... Arc tube 7...
AC power supply 8...Arc 9...Magnetic field generation mechanism Agent Patent attorney Noriyuki Chika (and 1 other person) Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A high-pressure metal vapor discharge lamp that is lit horizontally, and an alternating magnetic field with a frequency of 200 Hz or less is used for the arc of the high-pressure metal vapor discharge lamp to expand the arc.