JPS60127633A - Production of metal vapor discharge lamp - Google Patents

Abstract

PURPOSE:To prevent a luminous material from being evaporated and scattered due to radiation heat and stabilize the lamp characteristics by injecting the seal luminous material into a reservoir section provided at one block body of a luminous tube bulb and sealing with the other block body by heating. CONSTITUTION:One opening of a luminous tube bulb 1 made of a translucent ceramic tube with both ends opened is sealed with a block body 2A supporting an electrode 5A and provided with a recessed reservoir section 6 of a seal luminous material at the inner center via glass solder 3. Next, a granular amalgam 7 made of sodium and mercury, which is a luminous material, is dripped and injected to the reservoir section 6, further the starting rare gas is introduced, then the other opening is sealed with a block body 2B supporting an electrode 5B by heating via a seal material 3 to form the luminous tube. Accordingly, the luminous material 7 is prevented from being evaporated by shielding the radiation heat during heating with the electrode 5A, thus the characteristics can be stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing a metal vapor discharge lamp using a translucent ceramic tube as an arc tube bulb.

[Technical background of the invention and its problems]

Metal vapor discharge lamps, such as high-pressure sodium lamps, which use translucent ceramic tubes as arc tube bulbs are known as lamps with high luminous efficiency.

Recently, from the perspective of energy saving, this type of lamp has become smaller and smaller.
There is a growing demand for improvements as indoor light sources by lowering the wattage. For example, the color rendering properties of high-pressure sodium lamps used as indoor light sources must be improved, and for this purpose it is necessary to maintain the temperature of the coldest part of the arc tube high.

By the way, unlike quartz glass tubes, it is difficult to thermally process translucent ceramic tubes, so the tube end opening is fixed with a separate closing body. Niobium gaps and ceramic disks are known as the closing body, and these are hermetically joined to the translucent ceramic tube with a glass or metal lid. The interior of such an arc tube must be evacuated and filled with a predetermined luminescent metal (luminescent substance) and a starting rare gas, and the following methods are used to seal the exhaust.

In one method, an exhaust pipe such as a nioptic tube is passed airtight through the center of the closing body, and an electrode is attached to the inner end of this exhaust pipe, and the exhaust and the injection of the inclusions are performed through this exhaust pipe. .

In this case, the outer end of the exhaust pipe is sealed (tip-off) after exhaustion and filling are completed. However, in this sealed end, the outwardly projecting tip of the closure body becomes the coldest part, and it becomes difficult to raise the temperature of this coldest part.

Therefore, this product is not very useful for improving color rendering properties, and is not suitable for use as an indoor light willow due to its small size and low wattage.

Instead of this method, for example,
An exhaust gas sealing method disclosed in Publication No. 0 is known.

In this method, a ceramic tube whose one end has been previously sealed with a closing body is placed vertically in a bell jar with the closed end side facing downward, and the inside of the bell jar is replaced with the same gas as the starting rare gas. A luminescent metal is dropped through the opening, and the upper opening is then sealed with a closing body.

This method is called a tipless type because it does not use an exhaust pipe.9The coldest part is formed near the blockage in the pipe, that is, at the end of the pipe, so compared to the tip-off type, the coldest part is formed during lighting. The temperature can be maintained at a high temperature, which is effective in improving color rendering properties.

However, in the above chipless type, the following problems occur during the evacuation and sealing steps.

That is, in order to seal the upper end of a ceramic tube in a bell jar, the sealing location is heated to near the melting point of the ceramic tube. During this heating, the luminescent material that has already been put into the ceramic tube is evaporated and scattered by the radiant heat and escapes to the outside of the ceramic tube, making it impossible to obtain the desired luminescent characteristics. Large, high-output rungs have a long blue light length, and when heating the top opening, it is difficult for the heat to reach the luminescent material thrown at the bottom, but it is below 100 watts, which is desired to be developed as an indoor light source for general homes. In small, low-wattage lamps with tube lengths of 70 to 60 mm or less, the heat source is close to the luminescent material, so radiant heat causes significant scattering and loss of the luminescent material.

Furthermore, in small, low-wattage lamps, only a small amount of the luminescent substance is filled in, and slight changes in the amount of filled material greatly affect the lamp characteristics, so when manufacturing this type of lamp, it is important to minimize the loss of the filled material. had become a major issue.

[Object of the invention j.

The present invention has been made to address the above drawbacks.

A metal vapor modification with stable characteristics that prevents the enclosed luminescent substance from scattering and disappearing outside the tube during the manufacture of arc tubes.

[Summary of the Invention] The present invention aims to provide a method for manufacturing a metal vapor discharge lamp that can produce a light emitting lamp. The above %tlK of radiant heat generated when heat sealing the other end opening of the light tube pulp with the other end of the luminescent material sealed in the center of the inner surface of one of the closing bodies through the sealing material. It is designed to prevent Mk.

[Embodiments of the invention]

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

FIG. 1 shows an arc tube for a high-pressure sodium lamp manufactured by the method of the present invention, and FIG. 2 shows a state diagram of one end of the arc tube during the manufacturing process. This arc tube is normally housed in an outer tube (not shown). The lamp is completed.

In Fig. 1, the arc tube is made of translucent ceramics, such as high-density polycrystalline alumina ceramics, with an inner diameter of 5.5 mm.
The openings at both ends of the arc tube bulb (1) with a length of 28 mm and a length of 28 mm are covered with a closure body (2A) made of alumina ceramics, for example.
2B), the incoming material is airtightly sealed via a glass powder (3) whose main components are Al2O3 and Ca0.

One end of the lead-in wire (4A), (4B) made of a heat-resistant metal such as niobium, which airtightly penetrates the center of each closing body (2A), (2B) through a sealing material (3) such as a glass solder. Electrodes (5A) and (5B) are supported, respectively.

Further, inside the two arc tubes, sodium, which is a luminescent metal, is sealed in the form of an amalgam (sodium Na-mercury Hg) together with a starting rare gas.

Next, an embodiment of a method for manufacturing such an arc tube will be described. First, as shown in FIG. 2, an electrode (5A) is supported at one end opening of an arc tube bulb (1) with both ends open.
Then, it is sealed via a glass lid (3) by a closing body (two people) having a concave recess (6) for the enclosed luminescent substance in the center of the inner surface. Next, from the unsealed other end opening of the arc tube bulb (1), sodium Na and mercury Hg, which are luminescent substances, are removed.
When a granular amalgam (7) consisting of This step is preferably carried out in an inert gas to prevent deterioration of the amalgam.

Next, the amalgam (7) is placed in a closed container such as a bell jar in a vertical position as shown in Fig. 2.
If the airtight container is replaced with a starting rare gas such as (Ne-A, r) mixed gas, the above (N
e-Ar) mixed gas will be introduced. After passing through each of these steps, - open the other end opening of the unsealed side of the arc tube bulb (1) to the other closing body (5B) supporting the electrode (5B);
2B) through the sealing material (3).

At this time, the radiant heat generated in the heat sealing process tries to reach the amalgam (7) that was sealed in the previous process, but
Since the reservoir (6) of the amalgam (7) is located below the electrode (5A), this electrode (5A) acts as a shield for radiant heat, and therefore the radiant heat has difficulty reaching the amalgam (power), and the amalgam ( 7) is prevented from disappearing outside the arc tube bulb (1) due to evaporation and scattering.

Note that the maximum diameter of the luminescent substance reservoir (6) is the electrode (5A).
It is most preferable to form it so that it is smaller than the maximum diameter of.

Furthermore, the amalgam (7) is brought into contact with the electrode shaft or the electrode lead-in wire, and the portion of the lead-in wire (4A) outside the arc tube is cooled (not shown).

Since the filled material is cooled by the lead-in wire, which has better thermal conductivity than the Cenomics, the loss of the filled material is further suppressed, and a lamp with good and stable characteristics can be obtained.

FIG. 3 shows a modification of the luminescent substance reservoir (6).

The same parts as those shown in the second figure are denoted by the same reference numerals, and the description thereof will be omitted. In this example, the entire inner surface of one of the closing bodies (two persons) forming a reservoir (6) of the luminescent substance is made into a needle-like shape, so that the luminescent substance is moistened in the central part thereof. With such a shape, the luminescent substance to be dropped and sealed can be easily collected at the base of the electrode (5A), that is, at the position directly below, and radiant heat can be avoided using the electrode (5A) as a shield.

In addition, various modifications can be considered to the shape of the reservoir (6), such as making the circumferential surface of the recess itself sloped to form a needle-like shape, as shown in the second figure.

2. The present invention is not limited to the above embodiments.
Ittria is used as a material for arc tube bulbs.

Metal oxide single crystals such as magnesia, quartz ruby, and sapphire may be used, and furthermore, it can be applied to lamps containing other metals or metal halides as luminescent substances.

〔Effect of the invention〕

As described above in detail, according to the present invention, the encapsulated luminescent substance is stored in the depression formed at the center of the inner surface of one of the previously sealed closures, while being heat-sealed with the other closure. As a result, radiant heat is blocked by one electrode and cannot reach the luminescent material (1) Evaporation and scattering of the luminescent material can be prevented, and therefore a lamp with stable characteristics can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a front view of a high-pressure sodium lamp arc tube manufactured by the method of the present invention, FIG. 2 is an explanatory diagram of one embodiment of the method for manufacturing the arc tube, and FIG. 3 is an explanatory diagram of another embodiment. are shown respectively. (1)... Arc tube bulb, (2A), (2B) - Closure body. (3)...Glasunruda9 (4A)l (4B>・
・Introduction line. (5A), (5B)... Electrode, (6)... Luminescent substance reservoir. (7)... Amalgam (luminescent material) Agent Patent attorney Norihiro Chika (and 1 other person)

Claims (1)

[Claims] One end of the arc tube bulb, which is made of a translucent ceramic tube with both ends open, supports an electrode and is sealed via a sealing material with one closing body that supports an electrode and has a reservoir for the encapsulated luminescent material in the center of the inner surface. a step of sealing a luminescent substance from the other end opening of the arc tube bulb and storing it in a reservoir of the closing body; a step of introducing a starting rare gas into the arc tube bulb; 1. A method for manufacturing a metal vapor discharge lamp, comprising the step of: heating and sealing the other end opening of the arc tube bulb with the other closure member supporting the electrode via a sealing material.