Sealing lighting device component assembly with solder glass preform by using infrared radiation

Abstract

Disclosed is a method for sealing and affixing a component assembly for an electrical lighting device to a glass lamp envelope. The assembly used in the process comprises the component, such as an electrode lead wire and a solder glass perform. The process is useful, for example, in hermetically sealing and affixing lamp components, such as electrical lead wires and exhaust tubulation, to a low pressure fluorescent discharge lamp envelope having phosphor coating already applied thereto. The present invention is particularly suitable for lamp envelope made of borosilicate glass having a CTE from 0 to 300 DEG C. in the range of 30-45x10<-7> DEG C.<-1>.

Description

field of invention [0001] The present invention relates to the process of sealing to glass bulbs of electrical lighting equipment with infrared radiation. More particularly, the invention relates to the process of sealing component assemblies comprising welded glass preforms to lamp components using infrared radiation. For example, the present invention can hermetically seal lamp components such as electrical leads and vents to a phosphor-coated low pressure fluorescent discharge bulb. Background of the invention [0002] Electrical lighting equipment, including incandescent, fluorescent high-intensity discharge and halogen lamps, and cathode ray tubes, usually consisting of a hermetically sealed glass bulb to which electrodes, incandescent filaments, exhaust pipes, and other components are hermetically sealed . Electrodes and incandescent filaments are generally installed in glass bulbs, and electrode leads must be airtightly sealed with glass bulbs. In many of these lum...

AI Technical Summary

Problems solved by technology

The helical channel shape often requires sealing on flat surfaces with glass thicknesses less than 1mm. Although this is possible, the flames that machine the glass elements onto the flat surface generally create deformed sealing areas, which in turn affect the overall thickness and mechanical strength of the lamp.

Second, these large and complex-shaped bulbs are extremely sensitive to temperature differences, and the temperature differences involved in flame sealing can easily cause them to rupture

Third, the fluorescent layer, getter and electrodes are sensitive to high temperature, and exposing the fluorescent layer to temperatures above 600°C will significantly weaken its function, reduce lamp output, and shorten life

Applying direct flame sealing technology by conventional methods often cannot avoid heating the fluorescent layer, getter and electrodes which are generally not far from the sealing area

Thus, for example, certain natural outlets are destroyed or lamp elements deteriorate, lamp function malfunctions or lamp life is shortened, lamp brightness uniformity is reduced

Fourth, in many lamp applications, the hole to be sealed is much larger than the solder glass bead on the bead lead, making it difficult, if not impossible, to seal the bead lead directly to the glass bulb using conventional flame sealing techniques.

However, finding the right solder glass and method of sealing the lamp element to the borosilicate bulb was a challenge

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