JPS5975556A - Metal vapor discharge lamp - Google Patents

Abstract

PURPOSE:To suppress the dispersion of the light flux, light color and lamp voltage by melting an exhaust pipe with an inner diameter of 3mm. or less to a luminescent tube and connecting an exhaust pipe with a larger inner diameter to the exhaust side end of the exhaust pipe with a smaller diameter. CONSTITUTION:A pair of electrodes 2 are sealed at both ends of a luminescent tube 1 made of quartz glass in a metal halide lamp. Starting rare gas, mercury, and metallic halogenide is sealed in the luminescent tube 1. An exhaust pipe 6 with an inner diameter of 3mm. or less is melted at the center of the luminescent tube 1, and an exhaust pipe 5 with an inner diameter larger than that of the exhaust pipe 6 is connected to the exhaust end side of the exhaust pipe 6. In addition, the length of the exhaust pipe 6 is set to 20mm. or less. Accordingly, the dispersion of the light flux, light color, and lamp voltage of a metal vapor discharge lamp can be suppressed, and the starting characteristics of the lamp can be stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to suppressing variations in luminous flux and light color of a metal vapor discharge lamp such as a metal halide lamp.

Figure 1 is a front view showing an example of the structure of a conventional arc tube of a metal halide lamp. (3) etc. Inside the arc tube (11, in addition to a starting rare gas and mercury, a metal halide is sealed.

(4) is a tip portion formed during tip-off after the evacuation process of the arc tube (1). Fig. 2 is a diagram showing the configuration of the arc tube (1) and the exhaust pipe (5) during the evacuation process. in.

Normal arc tube (inner diameter 31 nm welded to 11 + outer diameter 5
It is connected to the exhaust system through the exhaust pipe (5). Then, the heated gas is released from the arc tube (1), and the gas is released from the electrode (2).

After going through processes such as releasing purified gas from the filled material, the exhaust pipe (5
) Chip-off completes the arc tube (1) shown in Figure 1. In the conventional exhaust pipe (5) configuration like this, 1 In the case of a low-wattage metal halide lamp with a small inner diameter of the arc tube, the arc tube (1) shown in Figure 1 is completed after evacuation. The chip portion (4) occupies a large proportion of the entire arc tube (1).

Therefore, a phenomenon was observed in which the encapsulated metal halide condensed on the inner wall of the chip portion (4) during lamp lighting.

Therefore, the vapor pressure of the metal halide during lighting varies depending on the size and shape of the tip portion (4).

Also, the variation in lamp efficiency and single-color characteristics was extremely wide. Depending on the size of the tip part (4).

This has the disadvantage that the internal volume of the arc tube changes greatly, and as a result, the variation in lamp voltage is also large.

This invention was made in view of the above-mentioned conventional drawbacks, and consists of two types of exhaust pipes having different inner diameters, and the exhaust pipe with a smaller inner diameter is welded to the arc tube, and the exhaust pipe with a larger inner diameter is welded to the arc tube. The exhaust pipe is connected to the exhaust side end of the smaller exhaust pipe, and the inner diameter of the smaller exhaust pipe is smaller than that of the smaller exhaust pipe.

This makes it possible to greatly suppress variations in luminous flux, light color, and lamp voltage of metal vapor discharge lamps.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 is a front view showing the structure 7 of the arc tube (1) and exhaust pipes (5) and (6) of a metal halide lamp according to the present invention, and the same reference numerals as in the previous example indicate completely the same parts.

In the figure, (5) and (61 are two types of exhaust pipes with different inner diameters, and the exhaust pipe (6) with the smaller inner diameter is the arc tube (1).
An exhaust pipe (5) having a dog-shaped inner diameter is welded to the center of the pipe and is connected to the exhaust side end of an exhaust pipe (6) having a smaller inner diameter.

In order to investigate the effect of such an exhaust pipe (6), the following experiment was conducted.

First, as a conventional example sample, the configuration shown in Fig. 2 was used at 100W.
I made a metal halide lamp arc tube (1). The inner diameter of the arc tube (1) is 1 cm, and the distance between the electrodes is 1.8 cm.
The exhaust pipe (5) has an inner diameter of 3mm and an outer diameter of 5mm. With such a configuration, scandium iodide and sodium iodide were sealed together with appropriate amounts of rare gas and mercury into the arc tube (1) after completing the prescribed steps to complete the arc tube (1).

The differences between the upper limit values of the total luminous flux per color temperature and the lamp voltage of 10 conventional metal halide lamps were 3500/m, 2000/m, and 35 V, respectively.

In addition, as an example sample, an exhaust pipe with a small inner diameter (61%
- All other configurations were the same as the conventional sample.

The inner diameter of the small exhaust pipe (6) is 1.5mm.

The outer diameter is sum, the length is set to 5cm, the total luminous flux of 10 such example sample lamps is 1, the color temperature is 20001m, and the difference between the upper limit and the upper limit of the lamp voltage is 20001m and 6, respectively.
00K, 15V. moreover.

The average total luminous flux of the conventional example sample was 6,500 dm, but the average value of the example sample was 70,001 dm, and the total luminous flux (efficiency)
An improvement was also seen.

It should be noted that by changing the length of the exhaust pipe (6) with the small inner diameter, the lamp characteristics w R1)J were determined.If the length exceeds 20mm, the starting characteristics of the lamp in particular will be affected.

The characteristics were insufficient compared to lamps of 20 y+m or less.

This is because the length of the exhaust pipe (6), which has a small inner diameter, has a large effect on the conductance of the exhaust system.It should be noted that even metal halide lamps with fill compositions other than scandium iodide-sodium iodide and mercury lamps A similar effect can be obtained.

As explained above, the exhaust pipe for exhausting one arc tube consists of two types of exhaust pipes with different inner diameters, and the exhaust pipe with the smaller inner diameter is welded to the arc tube, and the exhaust pipe with the smaller inner diameter is welded to the arc tube. By making the inner diameter of the exhaust pipe smaller than 3 gates, variations in the total luminous flux, 9 color characteristics, etc. can be greatly reduced.

The present invention provides a metal vapor discharge lamp that has improved efficiency.

[Brief explanation of the drawing]

Fig. 1 is a front view of the arc tube of a conventional metalno-ride lamp, Fig. 2 is a configuration diagram of a conventional arc tube and exhaust pipe, and Fig. 3 is a diagram of the arc tube and exhaust pipe shown in Embodiment 2 of the present invention. 1 is a configuration diagram. In the figure, (1) is an arc tube. (5) is an exhaust pipe with a large inner diameter, and (6) is an exhaust pipe with a small inner diameter. Note that the same reference numerals in Figure 9 are the same or 41"1
This section is shown below. Agent Shin Kuzuno - Figure 1 Figure 2 Figure 4 Tithe■ Figure 3

Claims (2)

[Claims] (1) The exhaust pipe for exhausting the arc tube consists of two types of exhaust pipes with different inner diameters, and the exhaust pipe with the smaller inner diameter is welded to the arc tube, and the exhaust pipe with the larger inner diameter is welded to the arc tube. A metal vapor discharge lamp connected to the exhaust side end of the small exhaust pipe, and characterized in that the inner diameter of the small exhaust pipe is smaller than the previous one. (2) The metal vapor discharge lamp according to claim (1), characterized in that the length of the exhaust pipe with a small inner diameter is 20 mm or less.