JPH027494B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a lamp in which a limited airtight space is formed by a bulb having an open end and an end plate that closes the open end of the bulb, and in particular, Regarding the sealing method.

An example of this type of lamp is a small fluorescent lamp shown in FIG. 1, which is provided with an inner tube for regulating a discharge path. That is, in the figure, 1 is a glass bulb with one end open (hereinafter referred to as a bulb); 2
is an end plate that closes the opening of the bulb 1, and this end plate 2 has a groove 22 at a position corresponding to the opening end 11 of the bulb 1, and within this groove 22, the glass frit layer 3 is inserted into the bulb 1 to airtightly seal it. It is worn. 4 is a pair of electrodes provided on the end plate 2; 5 is two U-shaped glass inner tubes with a phosphor layer 6 coated on the inner surface;
One end encloses one of the electrodes 4 and is fixed on the end plate 2, the other end is opened near the end plate 2, and the electrode 4
The discharge generated between the openings is restricted to two continuous U-shapes through this opening. Reference numeral 7 denotes a thin exhaust tube provided on the end plate 2.

In the lamp constructed in this manner, the end plate 2 and the bulb 1 are generally sealed together via the glass layer 3 as follows. That is, after placing the electrode 4, inner tube 5, and exhaust tube 7 on the end plate 2 in advance, as shown in FIG. The end plate 2 is made by mixing the adhesive with a vehicle and making a paste.
After filling the grooves 22 to the fullest and drying them to form the glass frit layer 3, the open end 11 of the bulb 1 is placed on the glass frit layer surface 34 as shown in FIG. Heating at a heating temperature to melt the glass frit layer 3,
The open end 11 of the bulb 1 was sunk into the groove 22 by its own weight, and was cooled to form the glass frit layer 3 and complete the sealing.

However, in such a method, the glass frit layer 3 contains a large amount of air bubbles inside before heating, and by heating and melting these air bubbles, the air bubbles escape and the glass is made into a volume-shrinked state. The glass frit layer 3 is formed in the shape of the glass frit layer 3. Therefore, in order to sufficiently hermetically seal the end plate 2 and the bulb 1, the glass frit layer 3 must be
In anticipation of the volumetric shrinkage of the glass frit, it was necessary to increase the thickness of the grooves 22 of the end plate 2 to the maximum depth _H1 as described above. Therefore, when heating and melting the glass frit with the bulb 1 placed on the dried glass frit layer 3, the glass frit layer 3 melts and the open end 11 of the bulb 1 sinks into the groove 22 of the end plate 2. Another drawback is that the valve opening end 11 is displaced from the groove 22 due to external forces such as vibrations, and is often not sealed within the predetermined groove 22. On the other hand, in order to eliminate such deviation, it is conceivable to reduce the filling thickness of the glass frit layer 3 or to increase the depth _H1 of the groove in the end plate 2. In the former case, the amount of glass frit in the sealed portion is insufficient, resulting in a decrease in the reliability of the airtightness of the sealed portion. In the latter case, processing of the end plate 2 becomes difficult.

This invention was made to eliminate such manufacturing defects, and when sealing an end plate to the open end of a valve, a groove corresponding to the open end of the valve is provided in advance in the end plate, and this groove is Filling the inside with glass frit, heating and melting it to form a glass frit layer in the groove with a height smaller than the depth of the groove,
Thereafter, the open end of the bulb is placed on the glass frit layer, and the glass frit layer is heated and melted again in this state, thereby providing a method for manufacturing a lamp that can improve the reliability of the airtightness of the sealed portion. be.

According to this method, once the glass frit layer is heated and melted, air bubbles in the layer escape, and by cooling the layer, the glass frit can be formed into a glass-like layer in a volumetrically contracted state. Once the glass frit has become such a glassy layer, even if it is heated and melted again, the volume hardly changes, and it only melts and solidifies reversibly with temperature. Therefore, in this method, the volumetric shrinkage of the glass frit layer is caused,
A level difference sufficient to support the bulb is formed in the groove of the end plate, and the open end of the bulb is placed and supported on the glass-like glass frit layer forming this level difference, so that when the glass frit layer is reheated, The valve will no longer be misaligned. Therefore, the reliability of the airtightness of the sealed portion is improved.

Further, since the vehicle in the glass frit layer is completely decomposed and discharged by the initial heating and melting, the sealing with the bulb prevents the vehicle from being trapped inside the bulb and depositing inside the lamp.

Next, as an embodiment of the present invention, a case where the present invention is applied to the manufacture of a small fluorescent lamp will be described with reference to FIGS. 4 to 7.

In these figures, 1 is a cylindrical soda lime glass bulb with an open end, and the main body 12 of this bulb 1 has an outer diameter B ₁ of about 60 mm, and this body 12 also has an outer diameter B _{2 .} is approximately 56mm thick.
An open end 11 having a diameter B ₃ of approximately 3 mm and an outer diameter B ₂ of approximately 56 mm is integrally formed. 2 has an outer diameter D ₁ of approximately 60 mm and a plate thickness t of approximately 3.5 mm that closes the open end 11 of this valve 1.
mm forsterite (2Mgo.Sio ₂ ) ceramic end plate, and this end plate 2 has an inner diameter D ₃ of about 48 mm, an outer diameter D ₂ of about 58 mm, and a depth H ₁ concentric with the outer diameter D ₁ . A groove 22 with a diameter of about 1.5 mm is integrally formed. Incidentally, except for what is shown, the lamp configuration is the same as that shown in FIG. 1 described above.

In this structure, the end plate 2 and the bulb 1 are sealed together by first adding a glass frit containing lead oxide and boric acid as main components and having a softening temperature of 370°C to a vehicle prepared by dissolving 1 g of nitrified cotton in 100 ml of isoamyl acetate. Add 700g of and knead to make a paste.

Next, as shown in FIG. 4, this paste is
The grooves 22 of the end plate 2, in which electrodes, inner tubes, and exhaust tubes (these are omitted) are filled in advance to the depth _H1 of the grooves 22, and then dried to form a glass frit. Get layer 3.

Next, this was placed in a heating furnace (not shown) and heated to 450
The glass frit layer 3 is heated to 0.degree. C. and kept at this sealing temperature for about 5 minutes to melt it, and then cooled to obtain a glass frit layer 3 having a height _H2 of about 0.8 mm as shown in FIG.

Thereafter, as shown in FIG. 6, the open end 11 of the bulb 1 is placed on the glass layer surface 34, and in this state it is placed in the heating furnace again to re-melt the glass frit layer 3 at the above-described sealing temperature. If this is then cooled, the sealing will be completed in the state shown in FIG.

As a result of making 50 lamps using this method and examining the misalignment of the seal between the end plate 2 and the bulb 1, there were no defects where the open end 11 of the bulb 1 protruded from the groove 22 of the end plate 2. It was hot.

On the other hand, in addition to the above-described implementation, the present inventors have further developed a glass frit layer 3 obtained by varying the height of the glass frit layer filled in the groove 22 of the end plate 2.
When the height _H2 of the glass frit layer 3 was changed and the open end ₁₁ of the bulb 1 was placed and sealed with the height H2 of each glass frit layer 3, the glass frit layer 3
It has been found that airtight sealing can be sufficiently ensured by setting the height H ₂ to 0.5 mm or more. The reason why an airtight seal was obtained without increasing the height of the first glass frit layer 3 to the depth _H1 of the groove 22 is that by the time the open end 11 was placed, the air bubbles had already escaped sufficiently. This was due to the improved tightness of the glass frit layer 3. Furthermore, the difference in depth between the glass frit layer 3 and the groove 22, that is, the actual groove depth _H3 when the opening end 11 is placed.
It was also found that if the distance is 0.3 mm or more, an effect equivalent to that of the above-mentioned embodiments can be obtained with respect to positional deviation. Furthermore, if we take into consideration the workability of the groove 22 itself of the end plate 2 and the efficiency of applying glass frit paste without impairing these effects, the depth of the groove 22 H ₁
The preferable range was 0.9 to 2.0 mm.

Furthermore, in this embodiment, the end plate 2 is made of a forsterite ceramic plate, but it goes without saying that the same effect can be obtained by using other glass plates, metal plates, etc. be. However, due to the workability of the groove 22 and the end plate 2 being heated at least twice, the end plate 2
Ceramic end plates would have been more suitable as they would oxidize more easily.

Furthermore, it is obvious that this method can also be applied to other lamp manufacturing methods in which the bulb and end plate are sealed together. Furthermore, it has been confirmed that the glass frit is not limited to paste-like ones, but can also be applied to pellet-shaped ones.

As detailed above, in the method of the present invention, when sealing an end plate to the open end of a bulb, a groove corresponding to the open end of the bulb is provided in the end plate, and the groove is filled with a material mainly containing low-melting glass powder. The glass frit is filled with paste-like or pellet-like glass frit, heated and melted to form a glass-like shape, and the height of the glass frit is made smaller than the depth of the groove.Then, the open end of the bulb is placed on the glass frit layer. Since the glass frit is reheated and melted in this state, it is possible to prevent misalignment between the opening end of the bulb and the groove of the end plate, and there is an advantage that the reliability of the airtightness of the sealed portion can be improved.

[Brief explanation of drawings]

Figures 1 to 3 are diagrams explaining the conventional manufacturing method, in which Figure 1 is a partial cross-sectional view showing a partially expanded lamp, and Figures 2 to 3 are enlarged cross-sections of important parts showing the order of the manufacturing process. 4 to 7 are enlarged sectional views of main parts showing the manufacturing method of the present invention in the order of manufacturing steps. In the figure, 1 is a bulb, 11 is an open end, 2 is an end plate, 22 is a groove provided in the end plate, and 3 is a glass frit layer. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] 1. When simply sealing the end plate of the bulb opening, a groove corresponding to the opening end of the bulb is provided in the end plate, and a paste-like or pellet-like glass frit mainly composed of low-melting glass powder is placed in this groove. The glass frit is heated and melted to make it glassy, its height is smaller than the depth of the groove, and then the open end of the bulb is placed on the glass frit layer, and the glass frit is reheated in this state. A method for producing a lamp characterized by melting the lamp. 2. The method of manufacturing a lamp according to claim 1, wherein the material of the end plate is ceramic. 3. Claims 1 or 2, characterized in that the height of the glass frit layer formed in a glass shape is 0.5 mm or more, and the difference between the depth of the groove and the height of the glass frit layer is 0.3 mm or more. Method for manufacturing the lamp described in Section 1. 4. The method for manufacturing a lamp according to any one of claims 1 to 3, wherein the depth of the groove is 1.0 to 2.0 mm.