Combined HID electric arc tube

Abstract

A composite type HID electric arc tube comprises a discharge tube and two outlet tubes. The discharge tube is a composite type double-layer shell body, the casing of which is formed by blowing meltdown quartz glass or Bach quartz glass, and the inner side of which is coated with a semi-transparent polycrystal alumina(PCA) layer. The outlet tubes are made of the meltdown quartz glass or the Bach quartz glass. The insides of the two ends of the two outlet tubes close to an electric arc cavity body are partially coated with a polycrystal alumina layer. After being sintered at the high temperature, the electric arc tube adopts the method of sealing electrodes at two sections. The first sections of the outlet tubes internally coated with PCA adopt glass solders for sealing, and the second sections thereof adopt molybdenum foil press seal. The HID electric arc tube with the structure has the advantages of easy shaping of quartz glass electric tubes, good voltage resistant property, standardphysical dimension inside the PCA electric cavity body, high temperature resistance and strong sodium penetrability resistance. In addition, the electric arc tube can improve the HID, particularly, photochromic stability and light efficiency of MH light, and prolong the service life of the light.

Description

technical field [0001] The present invention relates to arc tubes used in lighting equipment, in particular to composite HID arc tubes used in high-pressure gas discharge lamps (HID). Background technique [0002] Generally, fused silica glass is selected as the material for HID arc tubes, because the arc tubes made of this glass have good pressure resistance characteristics under high temperature working conditions, and can withstand about 200-300 atmospheres; on the other hand, Arc tubes made of quartz glass are easily sealed. However, quartz glass also has obvious disadvantages. On the one hand, the quartz glass arc tube is hot-melted at high temperature and is extruded by an outer mold while the inner cavity is blown into high-pressure air to form it. The size of the inner cavity becomes an uncontrollable free working difference; As a result, the arc tube working at high temperature changes with the change of lamp ignition angle (up to 360°) and the color temperature ca...

AI Technical Summary

Problems solved by technology

Due to the shortcomings of PCA's own pressure difference (only about 3-5 atmospheres), the arc tube made of ceramics is difficult to actually package the electrodes. It is not easy to fill the metal halide pellets, inject mercury, fill various inert gases, and rely on glass solder to achieve an airtight seal between the outer lead of the electrode and the ceramic material. Failure in one step will waste all previous efforts and seriously affect the overall qualification rate of ceramic arc tubes, which not only keeps the cost high

Moreover, the current technology can only be used for arc tubes with small and medium power below 150w, and there is no example of popular commercial application for high power above 250W to several KW. Not promoted and popularized

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