JPS60124348A - Metallic vapor discharge lamp - Google Patents

Abstract

PURPOSE:To make it possible to greatly improve the efficiency by filling the gap between a warm-keeping element and a fluorescent tube with a heat-resisting fiber. CONSTITUTION:After one end of a quartz glass tube is heated and softened, a warm-keeping element 6 is formed in accordance with the shape of a fluorescent tube 1 so as to provide a prescribed gap between the fluorescent tube 1 and this warm-keeping element 6. Furthermore, in the gap between the fluorescent tube 1 and the warm-keeping element 6 especially around the portions which don't need the transmittance of light, a quartz glass wool 9 is uniformly implanted as a heat-resisting fiber, and then the warm-keeping element 6 is fixed. In this way, the rise of the coldest temperature and the uniformity of temperature on the wall of the fluorescent tube can be realized and the metallic vapor discharge lamp with a good and long service life and high efficiency can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to metal vapor discharge lamps such as metal halide lamps and high pressure sodium lungs.

[Prior art]

Figure 1 is a front view showing the structure of a conventional metal halide lamp. is filled with rare gas, mercury, and metal halide.(3) is an outer tube, and nitrogen gas, for example, is sealed inside.(4) is QiW on the upper end of the outer tube (3), and electrode ( 2a) A cap electrically connected to (2b), (
5) is a heat insulating film formed of, for example, a zirconia coating applied to the lower end of the arc tube.

Since the vapor pressure of metal halides changes depending on the temperature of the coldest part, conventionally, as a means to increase the temperature of the coldest point to increase lamp efficiency, a metal halide was applied to the lower end of the arc tube, which is the coldest point. By making the zirconia coating (5) thicker, coating J! @
(The method used is to increase the fill width of 51.

However, when the thickness of the coating film (5) is increased.

It is difficult to maintain the stable characteristics of the coating film (5), and the coating peels off during the heat cycle during one lighting cycle, and the visible light emitted from the arc is absorbed due to the influence of the adhesive added to the zirconia. The proportion of people who are exposed to it increases.

Furthermore, the temperature of the arc tube near the area where the heat insulating film (5) has been applied becomes non-uniform, making it impossible to achieve a sufficient improvement in efficiency. Therefore, 2
Quartz glass or single crystal alumina.

Translucent polycrystalline alumina, translucent ceramic, and the like have been used as heat insulators.

FIG. 2 is a partially sectional front view showing a conventional example using a translucent heat insulating body made of quartz. 111 (2a) (2b)+
3+ +4+ indicates the same parts as the same reference numerals in FIG.
(6) is a transparent heat insulating body made of quartz in place of the zirconia heat insulating film in Figure 1, (7) is an arc tube holding plate, and (8) is a support frame.

The heat insulating body (6) is fixed to the retaining plate (7) by passing it through a hole provided in it, and both ends of the retaining plate (7) are attached to the support frame (
8).

However, in the above supporting method, since the heat insulating body (6) is supported only by the retaining plate (7), the gap distances a and b shown in FIG. Distance from the tip of the body to the tip of the heat insulator C'Jfr:
It is important to keep the dimensions accurately constant, and even after manufacture, there is a risk that the determined dimensions of a, 'b, and c may change due to vibration or external injury. This a, b.

If the distance C is not constant, the temperature of one arc tube will be non-uniform, and there is a drawback that a sufficient improvement in efficiency cannot be expected.

Further, in the above structure, the open portions at the upper and lower ends of the heat insulator (6).

Another drawback is that convective gas in the outer tube flows into the gap between the tgu+ and the heat insulator (6), making it insufficient to raise the temperature of the coldest point of the arc tube (1).

[Summary of the invention]

The present invention was made to eliminate such drawbacks, and by filling the gap between the heat insulator and the arc tube with heat-resistant fibers, the temperature at the coldest point increases and the wall temperature of the arc tube increases. The object of the present invention is to provide a metal vapor discharge lamp that achieves uniformity of energy consumption and thus enables a significant improvement in efficiency.

[Embodiments of the invention]

3 and 4 are partially sectional front views showing one embodiment of the present invention, respectively. In FIG. 1, (11 to f8) indicate the same parts as the same reference numerals in FIGS. 1 and 2. FIG.

(9) is a heat-resistant fiber filled in the gap between the arc tube (1) and the heat insulator (6).

Next, Figure 3, m 41! The specific structure of the embodiment shown in ¥1 will be explained in comparison with the conventional example shown in FIG. 2.

First, as a conventional example, a JR-made metal halide lamp shown in FIG. 2 was manufactured as follows.

The inner diameter of the arc tube (1) is 2Qwarn, and the electrode (2a)
(2b) 1 drop for 45 battles and 1 shot for Genshu' 11) 14.8 m9 of sodium iodide and 10.6 m9
20 Torr of mercury and argon gas are filled with scandium iodide, and the outer tube (3) is heated to 560 Torr.
Torr of nitrogen gas was sealed. Then, as a heat insulator (6), one end of a quartz glass tube with an inner diameter of 30mm and a wall thickness of 3m+* is heated and softened, and a predetermined gap is created between it and the arc tube (1) to match the shape of the arc tube ill. A heat insulating body (6) was formed by processing the heat insulating body (6), and the heat insulating body (6) was fixed to the holding plate (7) so that its upper end was located 10IIls above the tip of the electric wire (2b).

Lamp 10 with vertical lighting of the rung made in this way.
When we looked at the efficiency of books, the average efficiency was 109trry'*(
A minimum efficiency of 951 m 2 /W was obtained at 100 hours value).

The luminous flux maintenance rate of this lamp for 5 ooo hours of lighting was 46%.

Furthermore, as a result of vibration and impact testing of the above lamp, the dimensions of &, b, and c slightly changed.

It has been found that if the lighting time continues in this state, there is a risk of further reduction in efficiency.

In the embodiment shown in Fig. 3, one end of a quartz glass tube with an inner diameter of 30 mm and a wall thickness of 3 mm was heated and softened, as in the conventional example.
The heat insulating body (6) is formed by machining so that a predetermined gap is formed between the arc tube 111 and the heat insulating body (6) according to the shape of the arc tube II+, and the gap between the arc tube 111 and the heat insulating body (6), especially Quartz glass wool (9) was evenly embedded as a heat-resistant fiber around areas where translucency was not important.
) and a holding plate (
The bottom of the t'i warm body (6) was placed on top of the fM warm body (6) to prevent it from falling off in the vertical lighting mode. Also, electric @ (2b) core wire tip and heat insulator (
6) Distance from the top end? If', c is IQ+ as in the conventional example
++m. The average lamp efficiency of the prototype lamp manufactured in this way after 100 hours of vertical lighting was 1131 m/W, slightly improved compared to the conventional example, and the minimum efficiency was 1011 m/W, with some improvement in variation. Furthermore, when we conducted the same perturbation and impulse tests as in the conventional example, we found that the distance between the heat insulator (6) and the arc tube 111 was 1! No changes were observed in Ijia, b, and c, and the heat insulator (6) was completely fixed to arc tube +11.

Next, in the embodiment shown in FIG. 4, the gap between the upper and lower open ends of the heat insulator (6) and the 9 arc tubes tl'l is filled with heat-resistant fibers (9) made of quartz glass wool. Thereafter, the surface of the quartz glass wool (9) was hardened by heating to a state where it could be held. Also, the load capacity tc between the tip of the electrode (2a) and the upper end of the heat insulator (6) was set to 10 as in the conventional example. The average lamp efficiency of the prototype lamp manufactured in this way after 100 hours of vertical lighting was 1,241 m, and the luminous flux maintenance rate for 6,000 hours of one lighting at 7W was 68%.Both efficiency and luminous flux maintenance rate were improved compared to the conventional example. It was seen.

In the above example, a lamp for vertical lighting was described, but as a lamp for horizontal lighting, translucent heat insulators were provided at both ends of the nine arc tubes, and heat-resistant fibers were placed in the gap between these heat insulators and the arc tube. It may be filled.

〔Effect of the invention〕

Since the present invention is configured as described above, it has the effect of providing a metal vapor discharge lamp with good life characteristics and high efficiency.

[Brief explanation of the drawing]

1 and 2 are partially sectional front views showing a conventional metal vapor discharge lamp, and FIGS. 3 and 4 are partially sectional front views showing an embodiment of the present invention, respectively. In the figure, (1) is an arc tube, and (2a) and (2b) are electrodeposition. (3) is an outer tube, (6) is a heat insulator, and (9) is a heat-resistant fiber. Note that the same reference numerals in each figure indicate the same or corresponding parts. Figure 1 Figure 2 Figure 3 Figure 4 Continued from page 1 0 Inventor Yoshinori Takai Onboard Kamakura Heavy Ship

Claims (3)

[Claims] (1) An outer tube whose internal space is filled with a specified gas. A light emitting tube is installed inside the outer tube and has a transparent structure except for the sunrise part of the electrode, and a transparent light emitting tube is installed near at least one end of the light emitting tube and covers this end. 1. A metal vapor discharge lamp equipped with a photothermal heat insulator, characterized in that a gap between the heat insulator and the arc tube is filled with heat-resistant n-fiber. (2) The heat insulator is fixed to the arc tube by supporting the heat insulator on a holding plate that holds the arc tube, and filling the gap between the heat insulator and the arc tube with the heat-resistant tank fiber. A metal vapor discharge lamp according to claim 1. (3) The metal vapor discharge lamp according to claim 1 or 2, characterized in that the heat-resistant fibers are filled in the gaps between the heat insulating body and the arc tube at both open ends of the heat insulating body.