JPS6155849A - Fluorescent discharge tube - Google Patents

Abstract

PURPOSE:To produce a fluorescent discharge tube having excellent rising of luminous flux and stable characteristics by preventing any separation of second amalgam formation metals installed near the electrodes by specifying the amount of metallic mercury charged. CONSTITUTION:Stems 5 and 6 have fine tubes 7 and 8. At least one of the tubes 7 and 8 has a neck 9 which is charged with an amalgam formation metal 10. Second amalgam formation metals 11 and 12 for improving the rising of luminous flux are installed near the electrodes 3 and 4. After vacuum evacuation, the electrodes 3 and 4 are activated and a given amount of metallic mercury and a rare gas is charged into the emitter tube through the fine evacuation tube 8. The separation of the second amalgam formation metals 11 and 12 can be prevented by adjusting the amount of mercury charged in the emitter tube to a level of at most 10mg preferably at most 6mg. Accordingly, it is possible to produce a fluorescent discharge tube having excellent rising of luminous flux.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a fluorescent discharge tube in which the vapor pressure of mercury is controlled using an amalgam-forming metal.

[Background of the invention]

In order to obtain highly efficient and stable light output in high-output fluorescent discharge tubes and fluorescent discharge tubes with multiple inner tubes,
A fluorescent discharge tube in which mercury vapor pressure is controlled using amalgam-forming metals is shown, for example, in Japanese Patent Application Laid-Open No. 52-2034. Further, in the fluorescent discharge tube in which the amalgam-forming metal is provided to control the mercury vapor pressure, a first amalgam for controlling the vapor pressure of mercury in a steady lighting state is housed in a thin tube provided in the fluorescent discharge tube. 1. Providing a second amalgam near the electrode in order to improve the rise of the luminous flux at the start of lighting
Conference Preprint:
No. 64 (1983), Macdo
Nald, Johnson and L atassa
by “Compact Energy Sav”
Fluorescent Lamp wit
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Medium Screw Bass”.

These fluorescent discharge tubes suppress excessive increases in mercury vapor pressure even under high tube wall loads where the tube wall temperature is extremely high.
It has characteristics such as high efficiency, stable light output because there is little change in mercury vapor pressure even when the ambient temperature changes, and an excellent rise in luminous flux at the start of lighting. However, the first tube is installed in a part of the fluorescent discharge tube.
In a fluorescent discharge tube that houses an amalgam-forming metal and has a second amalgam-forming metal near the electrodes, if left for several days after manufacture, the second amalgam-forming metal will fall off and adhere to the tube wall of the fluorescent discharge tube. This phenomenon occurred, resulting in the disadvantage that the rise of the luminous flux was poor and the output characteristics varied.

[Purpose of the invention]

The object of the present invention is to prevent the second amalgam provided near the electrodes from falling off by limiting the amount of metal mercury enclosed, and to obtain a fluorescent discharge tube with excellent luminous flux rise and stable characteristics.

[Summary of the invention]

FIG. 1 shows a so-called saddle-shaped fluorescent discharge tube 1 made by further bending a glass tube bent into a U-shape. and 4 are provided, and these stems 5 and 6 are provided with capillary tubes 7 and 8, respectively, in which one of the capillary tubes, for example capillary tube 7, is formed with a neck 9 to carry an amalgam forming metal 10. It is enclosed. A second amalgam-forming gold layer x1t, 12 for improving the rise of the luminous flux is provided near the electrode 3.4 in order to rapidly raise its temperature. After the above fluorescent discharge tube is evacuated, the electrode 3.4
is activated, and a certain amount of metallic mercury and rare gas are sealed through the exhaust tube 8. If the fluorescent discharge tube provided with the second amalgam-forming metal 11, 12 is left for several days or more after manufacture, since the amalgam-forming metal 10 for controlling mercury vapor pressure is housed in the capillary tube 7, mercury will first be transferred to the electrode. It is alloyed with the second amalgam-forming metal 11.12 provided nearby. Generally this second amalgam-forming metal 11
．． Since 12 is in a small amount, it becomes liquid when alloyed with the mercury. Therefore, when this fluorescent discharge tube is subjected to vibrations, the liquid alloy falls off, and as a result, the second amalgam-forming metal 11, 12 moves to the tube wall. Since the tube wall has a large heat capacity and is far from the electrode 3.4, the temperature rise at the start of lighting is slow, and therefore the rise of the luminous flux is not altered. It is obvious that the above phenomenon is unique to fluorescent discharge tubes in which amalgam-forming metals are housed in thin tubes. The inventors of the present invention investigated the amount of mercury filled in and the dropout of the liquid alloy caused by the second amalgam forming metal 11.12 and water, and found the following relationship.

If the amount of mercury is more than 6 mg and less than 10 ffIg, it will hardly fall off due to the vibrations associated with normal transportation.

If the amount of mercury filled is more than 3 ■ and less than 6 ■, it will not fall off at all due to the vibrations associated with normal transportation.

The amount of mercury enclosed is 3 mg or less: Even if the fluorescent discharge tube is accidentally dropped, it will not fall off.

When the amount of mercury filled exceeded 10 μm, the occurrence of falling off rapidly increased.

In the fluorescent discharge tube in which the amalgam-forming metal 10 is housed in the thin tube 7 as described above and the second amalgam-forming metal 11, 12 is provided for improving luminous flux rise, the amount of mercury enclosed is more preferably 10 mg or less. is 6■ or less, the second amalgam-forming metals 11 and 12
It is possible to obtain a fluorescent discharge tube in which falling off can be prevented and the rise of the luminous flux is excellent.

[Embodiments of the invention]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a partial sectional view showing the first embodiment of the fluorescent discharge tube according to the present invention, FIG. 2 is a partial sectional view showing the second embodiment, and FIG. 3 is the third embodiment. FIG. The first embodiment shown in FIG. 1 is a fluorescent discharge tube made by further bending a U-shaped glass tube into a saddle shape, and the discharge tube 1 has an inner diameter of 1.5 mm and a discharge path length of 30 an. A phosphor layer 2 is provided on the inner wall of the inner tube. 150 mg of spherical bismuth-indium as an amalgam-forming metal 10 is placed in one of the thin tubes 7.8 provided with the neck 9 of the thin tubes 7.8 provided in the STETZ 5.6 supporting the electrodes 3.4 at both tube ends. I put it away.

The amalgam-forming metal 10 and mercury are sealed in the fluorescent discharge tube 1 as follows. First, a spherical or cylindrical amalgam-forming metal 10 is placed on the neck 9 provided at a predetermined position of the thin tube 7, and then the thin tube 7 is tip-sealed. Next, after evacuation is performed through the other capillary tube 8, a certain amount of mercury and rare gas are introduced from the same capillary tube 8 to seal off the capillary tube 8. The method for making the amalgam-forming metal 10 spherical is to inject the amalgam-forming metal molten in an inert gas from an appropriate nozzle, and rapidly cool the molten alkaline earth metal, which has become spherical due to surface tension. . Further, a cylindrical amalgam-forming metal can be obtained by cutting a linear amalgam-forming metal into a predetermined length. In any of the above cases, a constant amount of amalgam-forming metals can be obtained, and depending on the position of the neck 9 provided in the thin tube 7, these amalgam-forming metals can be placed in a fixed position, so that there is no variation in properties. A fluorescent discharge tube is obtained. The second amalgam-forming metals 11 and 12 for improving the rise of the luminous flux are indium plated nickel ribbons with a width of 0.2 ann and a length of 0.6 mm, and are attached to the lead wires of both electrodes 3 and 4, respectively. . After evacuation was performed through at\f8, 9 mg of mercury and argon gas were sealed at 3 Torr.

The saddle-shaped fluorescent discharge tube was housed together with a ballast in a glass bulb with a diameter of 11 square meters, and was lit at 18 watts.

In the fluorescent discharge tube of this example, the second amalgam-forming metal did not fall off, the luminous flux rise characteristics were excellent, and the light output was stable against changes in ambient temperature.

The second embodiment shown in FIG.
This is a fluorescent discharge tube in which a pair of inner tubes 14 and 15 are enclosed, each having an electrode at one end and an open end at the other end.The inner diameter of the inner tubes 14 and 15 is 1.3 an, and the discharge path length is 2.
6 countries, the diameter of outer tube 13 is 9 marks. In this embodiment, the thin tube 16 serves both as an exhaust pipe and as an amalgam-forming metal storage tube, and there is an advantage that only one thin tube 16 is required as shown in the figure. That is, in this embodiment, the thin tube 1 provided with the neck 9
After vacuum evacuation was carried out through No. 6, 5 mg of mercury and rare gas were added, and then amalgam-forming gold gC10 was introduced and sealed off. Second amalgam-forming metals 11 and 12 were attached to the leads of electrodes 3 and 4 in the same manner as in the first embodiment. A base (not shown) containing a ballast was attached to the fluorescent discharge tube purchased above, and the lamp was lit at 18W. The second amalgam-forming metals 11 and 12 did not fall off, and a good luminous flux was observed.

In the third embodiment shown in FIG. 3, three inner tubes 19, 20, and 21 are enclosed in an airtight space created by a ceramic substrate 17 and a glass outer tube 18, and a phosphor film 2 is formed on the inner surface of each inner tube.
One end of the inner tubes 20 and 21 has openings 22 and 23 facing each other into an airtight space.
One end of the inner tube 19 and the other end of the inner tube 20 are connected within the ceramic substrate 17, and electrodes 3 and 4 are provided at the other ends of the inner tubes 19 and 21, respectively. In a fluorescent discharge tube in which a large number of inner tubes are enclosed within an outer tube as in this embodiment, the temperature of the tube wall naturally becomes excessively high, so it is necessary to control the mercury vapor pressure using an amalgam-forming metal. However, the ceramic substrate 17, the outer tube 18, and the inner tubes 19, 20, and 21 are bonded together using low-melting glass powder and heated at several hundred degrees for several tens of minutes. It is impossible to insert the amalgam-forming metal in advance into the airtight space created by the outer tube 18 because the amalgam-forming metal will melt and flow or the amount of evaporation will increase. Therefore, after bonding the ceramic substrate 17 and the outer tube 18,
Glass capillary tube 1 bonded through ceramic substrate 17
The amalgam-forming metal 10 is housed in 6. In this embodiment, a thin tube 16 having a neck 9 is provided, and 40 mm of bismuth-indium is sealed as amalgam-forming gold@10.The thin tube 16 also serves as a vacuum exhaust tube. The second amalgam-forming gold rics 11 and 12 attached to the lead wires of electrodes 3 and 4, respectively, for improving the rise of the luminous flux, are small in amount so they do not flow off even at high temperatures, and the amount of evaporation is small, so they are sealed in an airtight space in advance. Is possible. When the above-mentioned fluorescent discharge tube manufactured with the amount of mercury enclosed being 2.5 mg was lit, the second amalgam did not fall off and the luminous flux had a good rise, as in each of the examples described above. Note that no change in characteristics was observed even after applying considerable vibration to the fluorescent discharge tube.

Each of the above explanations was made regarding fluorescent discharge lamps, but 1
It is obvious that the present invention can be applied immediately to any low-pressure mercury vapor discharge tube, such as a germicidal lamp.

〔Effect of the invention〕

As described above, the fluorescent discharge tube according to the present invention is a fluorescent discharge tube in which an amalgam-forming metal is provided to control mercury vapor pressure. The amalgam-forming metal of No.2 is provided near the 7i1 pole of the fluorescent discharge tube, and the amount of mercury enclosed is lOff.
By keeping it below Ig.

It is possible to prevent the second amalgam for improving the luminous flux rise from falling off, and it is possible to maintain good luminous flux rising characteristics during lighting.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view showing the first embodiment of the fluorescent discharge tube according to the present invention, FIG. 2 is a partial sectional view showing the second embodiment, and FIG. 3 is the third embodiment. FIG. 3.4... Electrode 7.16... Thin tube 10.
・・Amalgam forming metal

Claims (1)

[Claims] In a fluorescent discharge tube in which an amalgam-forming metal is provided to control mercury vapor pressure, a first amalgam-forming metal is housed in a thin tube provided in the fluorescent discharge tube, and a second amalgam-forming metal is placed near an electrode of the fluorescent discharge tube. 1. A fluorescent discharge tube characterized in that the amount of mercury enclosed is 10 mg or less.