JPH0430141B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for manufacturing a halogen light bulb.

Conventional structure and its problems When making a halogen light bulb using bromine or chlorine, if oxygen remains in the glass tube, the lifespan will be shortened. Therefore, it is necessary to remove oxygen from the bulb as much as possible. Conventionally, in general, an inert gas containing a few percent of hydrogen was filled into the glass tube during the exhaust process, the glass tube was heated from the outside with a burner, etc., and a filament was lit, and the heat generated inside the glass tube A method of reducing metal materials was used. However, since such a method cannot sufficiently reduce the metal material inside the glass tube, oxygen remains inside the glass tube, causing a short life.

OBJECTS OF THE INVENTION The present invention solves these problems, and provides a manufacturing method that allows a long-life halogen light bulb to be obtained without leaving oxygen in the glass tube.

Structure of the Invention According to the present invention, oxides of metal materials in the glass tube are reduced by the phosphine by filling the glass tube with an inert gas and a gas containing phosphine during the evacuation process.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

The figure shows a 100V500W single-ended halogen light bulb used for general lighting, where 1 is a glass tube made of quartz, 2 is a sealing part, and 3 is a double-coiled tungsten bulb installed inside the glass tube 1. 4 and 5 indicate internal lead-in lines, and 6 indicates a filament support line, respectively. The filament support wire 6 and the internal lead-in wires 4 and 5 are embedded in a glass rod-shaped body 7 by heating their bases. 8 and 9 are molybdenum foils, 10 and 11
is an external lead-in line.

In the halogen light bulb having such a configuration, the filament support wire 6 and the internal lead-in wires 4 and 5 are oxidized when the filament support wire 6 and the internal lead-in wires 4 and 5 are embedded in the glass rod 7 by heat processing. There are many things to do. The oxidation can be removed by chemical polishing or electrolytic polishing, but it is difficult to completely remove it. If a halogen light bulb is completed by sealing and exhausting with such oxidation remaining, and filling a small amount of halogen compound with an inert gas as the sealed gas, this halogen light bulb may cause early blackening or short life. It becomes a lifespan.

In order to solve these problems, it is necessary to remove the oxygen remaining inside the glass tube to the outside of the glass tube.

As mentioned above, in general, during the evacuation process, the glass tube is filled with an inert gas containing several percent hydrogen, the glass tube is heated from the outside with a burner, etc., and a filament is lit, and the heat is used to cool the glass. Methods have been used to reduce the metal materials inside the tube, but in order to reduce the oxidized metal materials inside the glass tube with hydrogen, it is necessary to bring the metal materials to a temperature of 1000°C or higher. However, in reality, metal materials other than filaments are heated to 1000℃.
It is difficult to heat above this level.

Therefore, we investigated a method to remove oxidation at a lower temperature.

The inventor first investigated the idea of filling an inert gas with a small amount of methylene bromide in the exhaust process and lighting the filament in the filled gas. When heated, methylene bromide decomposes into carbon and hydrogen bromide. At higher temperatures, hydrogen bromide decomposes into hydrogen and bromine. When this bromine combines with tungsten oxide, it becomes tungsten oxybromide. Tungsten oxybromide has a low evaporation temperature and is easily evaporated by heat from the filament and heat from a burner, etc. from outside the glass tube, so it can be exhausted outside the glass tube during exhaust work. It was considered. However, when we actually investigated the prototype, we found that it did not work as expected. It was found that the cause of this was that hydrogen bromide produced by decomposition of methylene bromide was hardly decomposed, so that sufficient bromine needed to evaporate tungsten oxide could not be obtained.

When the amount of methylene bromide in the filler gas was increased to increase the amount of bromine, progress was made in the desired direction for evaporating tungsten oxide, but the carbon released when methylene bromide decomposed was It adhered to the filament and caused brittleness of the filament and blackening of the tube wall, making it impossible to put it to practical use.

It was possible to sufficiently evaporate tungsten oxide using a sealed gas containing bromine in an inert gas without using a bromine hydrocarbon, but the exhaust machine would be attacked by the bromine, making it impractical. It was not possible to offer it to the public.

Therefore, the inventor investigated a method for reducing tungsten oxide without using bromine.

We investigated the use of a trace amount of phosphine together with an inert gas consisting of nitrogen, argon, or a mixture thereof as gases sealed in the glass tube during the evacuation process. When the filament inside the glass tube is lit, phosphin easily decomposes due to the heat and becomes PH and hydrogen. When the pH matches oxygen and tungsten oxide, they combine to form phosphorus monoxide. The phosphorus monoxide is exhausted out of the glass tube along with the inert gas.

In the case of hydrogen bromide, the bond between bromine and hydrogen is strong, so it was not possible to reduce tungsten oxide, but the affinity between phosphorus and oxygen is strong, so the PH
In this case, the bond between phosphorus and hydrogen is broken, and phosphorus removes oxygen from tungsten oxide to become phosphorus oxide, so tungsten oxide can be reduced.

As a result of experiments on the amount of phosphine sealed in an inert gas, it was found that if the amount was less than 0.1% by volume, the oxides inside the glass tube could not be removed, causing early blackening and shortening the lifespan of halogen bulbs. In addition, if the volume is more than 3%, the halogen cycle will be disturbed due to the phosphorus remaining in the glass tube.
Darkening often occurred.

Effects of the Invention As explained above, the present invention can provide a manufacturing method that allows a long-life halogen light bulb without oxygen remaining in the glass tube.

[Brief explanation of drawings]

The figure is a front view showing an example of a halogen light bulb according to the present invention. 1...Glass tube, 3...Filament, 4,5
...Internal introduction line, 6...Filament support line, 7
...A rod-shaped body.

Claims (1)

[Claims] 1. In the exhaust process of a halogen light bulb, a gas containing nitrogen, argon, or a mixture thereof containing phosphine is sealed in a glass tube, and the metal material in the glass tube is heated by lighting the filament, and at the same time, a gas is heated from the outside of the glass tube. After heating and reducing the oxide of the metal material in the glass tube with the phosphine and exhausting the generated oxide outside the glass tube, a gas consisting of an inert gas and a halogen compound is introduced into the glass tube. A method for manufacturing a halogen light bulb, characterized by encapsulating it.