DE3321479A1 - HIGH PRESSURE DISCHARGE LAMP - Google Patents

Description

Patent Trust Company

for electric light bulbs mbH, Munich

High pressure discharge lamp

The invention relates to a high pressure discharge lamp, consisting of a discharge vessel with an ionizable filling in which electrodes are fused. The discharge vessel has an envelope and it is also an intermediate vessel, for example for splinter protection, as a heat accumulating agent or as a scattering agent provided that partially surrounds the discharge vessel.

In DE-OS 28 40 771 a tundish is for heat accumulation purposes inserted- This is tubular here and surrounds the discharge vessel at a short distance. In the case of a lamp with a conventional frame structure, it is attached using two wire brackets attached to one of the holders for the discharge vessel designed as power supply lines are attached.

From DE-OS 30 28 405 a DC operated compact goes High-pressure discharge lamp, in which the discharge vessel is also surrounded by a tubular intermediate vessel. In this The latter case is provided to avoid Na diffusion from the discharge vessel (serves as an electrical screen) and is For this reason, a complicated frame structure - as can be seen from the figures - placed on a certain potential.

The object underlying the invention is to provide a simple, fastening of an intermediate vessel in the envelope of a high-pressure discharge lamp, which does not require a complicated or additional frame structure to accomplish.

According to the invention, the object is achieved with a lamp according to the preamble of claim 1 achieved in that the intermediate vessel is fused with the envelope piston.

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Advantageously, the invention relates to a one-sided crimped Discharge vessel in an envelope bulb pinched on one side. Since high-pressure discharge lamps of low output with halide filling, as they are currently for use in living and working areas are provided, have an operating pressure of approx. 30 bar (3 10 Pa) (this is significantly higher than the otherwise usual 3-5 bar (3 - 5 χ 10 Pa) with such high-pressure discharge lamps of greater power), an intermediate vessel increases for the purpose of splinter protection the safety of use of the lamp. In the event of the discharge vessel bursting the splinter particles either bounce off the intermediate vessel, or if their force is so high that the intermediate vessel itself is penetrated, its speed is reduced in such a way that the outer bulb withstands the impact in any case.

In addition, the intermediate vessel can be used for heat accumulation purposes or as a means of spreading. This is done with an or several UV- and / or IR-reflecting layers, one light-scattering Coating and / or provided with a surface matted by etching or sandblasting. Suitable as an IR-reflecting layer Sn-doped IruO "or SiO-TiO-.

The etching or sandblasting of the intermediate vessel surface causes that, partly due to total reflection, the radiation in the intermediate vessel has long path lengths and this radiation from the Intermediate vessel is absorbed to a greater extent. This leads to heating of the intermediate vessel, which in turn is advantageous the temperature in the discharge vessel.

It is also possible to make the intermediate vessel made of doped glass, for example made with Ti0 "-doped quartz glass, or from colored glass (filter glass). These glasses have the property of UV rays to absorb, which - as with the above-mentioned matting also - heats up the glass. These heat build-up measures can also take place directly on the discharge vessel. A colored intermediate vessel is used for a desired color correction Glass or coated with a fluorescent substance.

In one embodiment, the intermediate vessel is designed in the shape of a hood; In a further advantageous embodiment it is a tube, each with its upper end at or near the apex of the envelope is fused with the latter. As material for the different vessels, both quartz glass and hard glass are provided.

It is also conceivable to have intermediate vessels arranged in this way in lamps with a discharge vessel squeezed on both sides in one on one side to use squeezed envelope flask.

In a further embodiment of the lamp, the power supply lines angled towards the discharge vessel within the envelope so that the intermediate vessel is supported. This has the advantage that a higher strength is achieved at the fusion point. Another advantage is that the external power supply lines are wide be apart. This prevents possible leakage currents, the arcing distance is extended and you can use the lamp Hot-ignite a higher voltage surge.

The production of the metal halide high-pressure discharge lamp with the intermediate vessel according to the invention, which in the first exemplary embodiment is hood-shaped, is described in more detail below:

The envelope bulb required is made up of a rotating one around its longitudinal axis Glass pipe section produced by heating a pipe section to the softening temperature and constricting the pipe section by means of a roller to be moved in the direction perpendicular to the longitudinal axis. The envelope that has now been created is also at this point separated from the rest of the tube - but a central opening remains at the apex of the newly formed part. The hood-shaped intermediate vessel is produced in the same way, but from a glass tube with a smaller diameter is than that of the envelope piston. The intermediate vessel is placed in the envelope flask

inserted until the outer surface of the top of the tundish and the inner surface of the upper end of the envelope piston abut one another. Both vessels are at the point of contact by means of a Ring burner fused together and then attached the pump tube and also fused with the envelope piston.

When making the second version of the lamp with the tubular The intermediate vessel is inserted into the envelope and fused with its upper peripheral edge with the envelope. Then the pump tube is attached and also fused with the envelope.

The completion of the lamps in both exemplary embodiments takes place after known process steps: The already finished discharge vessel is introduced into the intermediate vessel in such a way that it is enclosed at least up to half its squeezed height. Now the envelope bulb is under Melting of the power supply lines and / or the molybdenum foils and the fastening wire of the getter holder squeezed, the inner volume of the envelope piston is evacuated via the pump tube and the pump tube is then melted. The lamp can also be equipped with a Be provided with a base.

Three embodiments of the lamp according to the invention are shown in the drawings and are described in more detail below. Show it

Figure 1 shows a first embodiment of a metal halide

High pressure discharge lamp with a dome-shaped

Intermediate vessel;
30th

Figure 2 shows a second embodiment of a metal halide

High pressure discharge lamp with a tubular

Intermediate vessel;

Figure 3 shows a third embodiment of a metal halide

High-pressure discharge lamp in which the intermediate vessel is supported.

The 40 W high-pressure discharge lamps 1, 1 ', 1 "shown in FIGS. ¹ to 3 each consist of a discharge vessel 2 pinched on one side and an envelope 3, 3 1, 3" also pinched on one side, which in these three exemplary embodiments are made of quartz glass . Two electrodes 4 are fused into the pinch 6 of the discharge vessel 2 by means of molybdenum foils 5. The molybdenum power supply lines 7, T, 7 "connected to the foils 5 simultaneously serve as a holder for the discharge vessel 2 and are in the pinch 9, 9 ', 9" of the envelope 3, 3', 3 "by means of further molybdenum foils 8. The lamp 1, 1 ′, 1 ″, on which a base (not shown) is arranged, is supplied with electrical current via the power supply lines 10 connected to these further foils 8.

The discharge vessel 2 has an internal volume of 0.2 cm ³ . The filling consists of 0.3 mg NaJ, 0.75 mg SnJ-, 0.06 mg TIJ and 8 mg Hg. Argon with a pressure of 100 mbar (ix 10 ⁴ Pa) is provided as the ignition gas.

The space in the envelope 3, 3 ′, 3 ″ is preferably evacuated. A getter, which arranged on a getter holder 11 and potential-free via the Fastening wire 12 is melted in the pinch 6 of the discharge vessel 2 or in the pinch 9 ″ of the envelope 3 ″.

Because of the high pressure prevailing in the discharge vessel 2 in the operating state, it makes sense to take precautions in the lamp 1, 1 ', 1 "to protect against splintering in view of possible bursting of the discharge vessel 2. It should be prevented that the Enveloping bulb 3, 3 ', 3 "is penetrated by splinter particles. An intermediate vessel 13, 13', 13" is provided as splinter protection

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- 8 is fused to the envelope 3, 3 ', 3 ".

In the exemplary embodiment according to FIG. 1, the intermediate vessel 13 is designed in the shape of a hood. It is fused to the envelope 3 in the area of its apex and surrounds the discharge vessel 2 at a small distance approximately up to half its squeezed height.

The exemplary embodiment according to FIG. 2 is similar to this the intermediate vessel 13 'the discharge vessel 2 also at the same small distance up to about half its squeeze height in an envelope 3 ', the dimensions of which correspond to the envelope 3 according to FIG. In this second embodiment a lamp 1 ', the intermediate vessel 13' consists of a cylindrical pipe section and is fused with its upper peripheral edge to the inner surface of the curved end of the envelope 3 '.

The lamp 1 ″ according to FIG. 3 has the same properties as the lamp 1 ′ according to FIG also a tubular intermediate vessel 13 ″ which closely surrounds the discharge vessel 2 at a small distance and which edge with its upper circumference is fused with the envelope 3 ″. This intermediate vessel 13 ″, however, extends with its length over the pinched area of the discharge vessel 2. The power supply lines 7 ″ leading to the discharge vessel 2 are angled and support the intermediate vessel 13 "at its lower circumferential edge. However, this has the consequence that the envelope 3" in its dimensions compared to the previously described embodiments of metal halide high pressure discharge lamps 1.1 'lower power must be greater, since the fuses of the power supply lines 7 ″ are further apart.

Goodbye / Ka

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Claims (12)

Claims {1.) High-pressure discharge lamp, which consists of a discharge vessel with an ionizable filling and fused-in electrodes and an envelope bulb enclosing the discharge vessel, an intermediate vessel being arranged between these two vessels, characterized in that the intermediate vessel (13, 13 ', 13 ") is fused to the envelope piston (3, 3 ^g , 3 "). 2. High pressure discharge lamp according to claim 1, characterized in that that the intermediate vessel (13) is hood-shaped and fused with its shaped upper end with the envelope piston (3) is. 3. High-pressure discharge lamp according to claim 1, characterized in that the intermediate vessel (13 ', 13 ") is tubular and one end ^{is fused to the envelope (3 1} , 3"). 4. High pressure discharge lamp according to claim 2 or 3, characterized in that that the power supply lines (7 ") to the discharge vessel (2) within the envelope (3") are shaped so that they support the intermediate vessel (13 ") at the end opposite the fusion. 5. High pressure discharge lamp according to claim 1 to 3, characterized in that that the intermediate vessel is coated. 6. High-pressure discharge lamp according to claim 5, characterized in that the intermediate vessel is provided with at least one IR-reflective layer and / or at least one UV-reflective layer.
30th 7. High pressure discharge lamp according to claim 5, characterized in that that the intermediate vessel "is provided with a light-scattering layer. 8. High pressure discharge lamp according to claim 7, characterized in that that the intermediate vessel is coated with phosphor. 9. High pressure discharge lamp according to claim 1 to 3, characterized in that that the intermediate vessel is etched or sandblasted. 10. High pressure discharge lamp according to claim 1 to 3, characterized in that that the intermediate vessel consists of doped glass. 11. High pressure discharge lamp according to claim 9, characterized in that that the intermediate vessel consists of quartz glass doped with TiOp. 12. High pressure discharge lamp according to claim 1 to 3, characterized in that that the intermediate vessel consists of colored glass.