JP2001068068A - Manufacture of tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture tubes at a low cost by suppressing the distortion of an arc tube and preventing the commercial value from dropping and the bulb from breakage. SOLUTION: Electrodes 2, metal foils 3, and leads 4 are set together and installed in a glass bulb 6, to whose one end an exhaust pipe 5 is put in communication, and the whole glass bulb 6 is heated by a burner 7. That end of glass bulb 6 located opposite the exhaust pipe 5 is crushed by pressure for sealing, and a seal part 1d is formed. Then a protective gas is fed from the exhaust pipe 5 into the glass bulb 6, and a swollen part 1b is produced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a tube.

[0002]

2. Description of the Related Art A conventional bulb, for example, a halogen bulb lit at a commercial voltage has a total length of 55 mm and a spheroidal inflatable portion 11a, as shown in a front view of FIG. 8 and a side view of FIG. Reduced diameter portion 11b and crushed sealing portion 11c
And an electrode 12 formed of a filament coil is provided in the arc tube 11. The maximum outer diameter of the inflated portion 11a is 14 mm.

[0003] A method of manufacturing such a halogen bulb is as follows.

As shown in FIG. 10, an exhaust pipe 13 is provided at one end.
Is heated and softened by a burner (not shown), and the end of the glass bulb 14 opposite to the exhaust pipe 13 is closed by a closing member 15 and protected from the exhaust pipe 13. While flowing the gas, a mold (not shown) is provided at the end of the glass bulb 14 on the exhaust pipe 13 side.
To form an inflated portion 11a and a cylindrical reduced diameter portion 11b.

[0005] Thereafter, as shown in FIG.
5 is removed, and the electrode 12 is disposed in the glass bulb 14. Next, after the cylindrical portion 14a of the glass bulb 14 on the side opposite to the exhaust pipe 13 is heated and softened by the burner 16, FIG.
As shown in FIG. 2, the mold 17 having an L-shaped cross section is crushed and sealed to form a crushed sealing portion 11c as shown in FIG.

After evacuating from the exhaust pipe 13, a predetermined amount of gas is sealed therein, and the exhaust pipe 13 is sealed to manufacture a halogen bulb.

[0007]

However, such a conventional method for manufacturing a halogen lamp has no problem in applying to a lamp which is operated at a commercial voltage, but is operated at a smaller voltage, for example, as low as about 12 V. When manufacturing a halogen bulb to be manufactured, after the inflated portion 11a and the reduced-diameter portion 11b are formed in advance, the crushed sealing portion 11c is formed. Due to the influence, the shapes of the bulging portion 11a and the reduced diameter portion 11b are distorted, and there is a problem that the commercial value is reduced.

The inflated portion 11a and the reduced diameter portion 11
Due to the distortion of the shape b, the thickness of the inflated portion 11a and the reduced diameter portion 11b varies, and as a result, the pressure of the sealed gas at the time of lighting (exceeding 1 atm) causes
There was a problem that was damaged.

Further, the inflated portion 11a and the reduced diameter portion 11b
Therefore, it is necessary to close the end of the glass bulb 14 on the side opposite to the exhaust pipe 13 with the closing member 15, so that there is a problem that the number of manufacturing steps increases and the cost increases.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and it is an object of the present invention to provide a low-cost tube which suppresses distortion of the shape of an arc tube and prevents reduction in commercial value and damage to a bulb. It is intended to provide a manufacturing method.

[0011]

According to the present invention, there is provided a method of manufacturing a bulb comprising a light emitting tube having an electrode provided therein and having an inflated portion and a crushed sealing portion. After the valve is softened in a state in which an electrode is disposed in a valve in which an exhaust pipe communicates with one end, an end of the valve opposite to the exhaust pipe is crushed and sealed, and then the exhaust pipe is closed. While the protective gas is flowing from above, a mold having a predetermined shape is pressed against the valve to form an inflated portion.

As a result, the shape of the arc tube can be suppressed from being distorted, and the manufacturing process can be simplified.

[0013]

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

A one-end sealed halogen lamp having a rated voltage of 12 V and a rated power of 50 W manufactured using the manufacturing method according to the embodiment of the present invention is shown in the front view of FIG. 1 and the side view of FIG. In addition, the total length is 43 mm, the closed portion 1a,
An arc tube 1 is formed by sequentially connecting an inflated portion 1b, a reduced diameter portion 1c, and a crushed sealing portion 1d.

A predetermined amount of a halogen element and a predetermined amount of a rare gas are sealed in the arc tube 1.

The inflated portion 1b is a spheroid. The focal length of this spheroid is 3.5 mm, and its outer diameter in the minor axis direction (the maximum outer diameter D of the inflated portion 1b) is 1
2 mm. The minimum outer diameter S of the reduced diameter portion 1c is 5.5.
mm.

An electrode 2 composed of a tungsten filament coil is provided in the inflated portion 1b.
The coil portion 2a of the electrode 2 has a length of 3.5 mm,
Both ends are located at the focal point of the spheroid. The electrode 2 is connected to a lead wire 4 via a metal foil 3 sealed in a crushable sealing portion 1d.

Next, a method for manufacturing such a halogen lamp will be described.

First, as shown in FIG. 3, an electrode 2, a metal foil 3 and a lead wire 4 are integrally formed in a cylindrical glass bulb 6 having an outer diameter d of 9 mm and having an exhaust pipe 5 connected to one end in advance. Place what is now. At this time, the electrode 2 is located at a portion where the bulging portion 1b of the glass bulb 6 is to be formed.

Note that the glass bulb 6 has an 8
A 214 fused quartz tube of mm (inner diameter) × 10 mm (outer diameter) was used.

Thereafter, as shown in FIG. 4, the entire glass bulb 6 is heated by a burner 7 of a mixed gas of oxygen and hydrogen while a protective gas such as nitrogen is introduced into the glass bulb 6 from the exhaust pipe 5. I do. The burner 7 includes a first burner portion 7a for heating a portion of the glass bulb 6 where the crushed sealing portion 1d is to be formed, and a second burner for heating a portion where the inflated portion 1b and the reduced diameter portion 1c are to be formed. 7b.

The crushed sealing portion 1d of the glass bulb 6
After the temperature of the part where the surface is to be formed reaches a predetermined temperature and softens, the flame of the first burner part 7a is stopped, and as shown in FIG. In the direction A, the end of the glass bulb 6 on the side opposite to the exhaust pipe 5 is crushed and sealed by the mold 8 to form a crushed sealing portion 1d as shown in FIG. Although not shown in FIG. 5 during the formation of the crushed sealing portion 1d, the portion where the inflated portion 1b and the reduced diameter portion 1c are to be formed is a second burner portion 7b
Continue heating by. Immediately after the crushed sealing portion 1d is formed, while the protective gas such as nitrogen flows into the glass bulb 6 from the exhaust pipe 5, the inflated portion 1b and the reduced diameter portion 1c are formed.
Are moved in the direction B, and the mold 9 is pressed against the glass bulb 6 to form an inflated portion 1b and a reduced diameter portion 1c as shown in FIG.
To form

Thereafter, after evacuation is performed from the exhaust pipe 5, a predetermined amount of a halogen element and a rare gas are sealed from the exhaust pipe 5, and the exhaust pipe 5 is sealed off, as shown in FIGS. Manufactures halogen bulbs.

Incidentally, the portion of the trace which has completely sealed off the exhaust pipe 5 becomes the closed portion 1a.

According to the manufacturing method of the present invention as described above,
Since the inflated portion 1b is formed after the crushed sealing portion 1d is formed, it is possible to suppress the shape of the arc tube 1 from being distorted,
It is possible to prevent a decrease in the commercial value and to prevent the thickness of the arc tube 1 from being varied, thereby preventing the arc tube 1 from being damaged. Further, when the inflated portion 1b is formed while the protective gas is flowing, the opposite side of the glass bulb 6 from the exhaust pipe 5 is closed by the crush sealing portion 1d, so that it is not necessary to use a closing member as in the related art. As a result, the manufacturing process can be simplified, and the cost can be reduced.

In particular, at the same time as the formation of the inflated portion 1b, the reduced diameter portion 1 is located between the inflated portion 1b and the crushed sealing portion 1d.
By forming c, for example, after forming the inflated portion 1b, compared with the case of forming the reduced diameter portion 1c, the reduced diameter portion 1 is formed.
Distortion of the shape of the arc tube 1 due to heat or the like when forming c can be further suppressed, and the manufacturing process can be further simplified.

In the manufacturing method of the present invention, since the swelling portion 1b and the reduced diameter portion 1c are formed by the mold 9, the mold 9 is formed on a part of the surface of the swelling portion 1b and the reduced diameter portion 1c.
However, since the streaks, ie, the mating shape remain, this mating shape is extremely thin and small, so that there was no problem in optical and appearance.

The outer diameter of the glass bulb 6 is defined as d (m
m), when the maximum outer diameter of the inflated portion 1b is D (mm), the strength of the inflated portion 1b can be improved by satisfying the relational expression of 1 ≦ D / d ≦ 1.8, and the arc tube 1 can be further prevented from being damaged.

On the other hand, when D / d> 1.8, the thickness of the inflated portion 1b becomes too thin, so that the strength is reduced and the portion is easily damaged. However, it is not practical because it is difficult to manufacture a product having D / d <1.

The minimum outer diameter of the reduced diameter portion 1c is S (mm).
By satisfying the relational expression of 0.5 ≦ S / d ≦ 1, the shape of the reduced diameter portion 1c can be stabilized and the optical characteristics can be prevented from changing. When pressed, the glass protrudes from the gap of the mold 9 and the arc tube 1
It is possible to prevent a large streak from being left and a decrease in commercial value.

On the other hand, when S / d <0.5, the reduced diameter portion 1c
Is formed, the reduced diameter portion 1c is crushed to form a meat pocket, and the optical properties are changed by the meat pocket.
Moreover, the meat reservoir contacts the electrode 2 and the coil portion 2a
Is tilted or decentered from the central axis of the arc tube 1, and the optical characteristics change. Furthermore, when the mold 9 is pressed, the glass protrudes from the gap between the molds 9, leaving streaks on the arc tube 1, thereby lowering the commercial value. Where S / d
> 1 is not practical because of the difficulty.

As shown in FIG. 7, tantalum oxide and silicon oxide are formed on the outer surfaces of the inflated portion 1b and the reduced diameter portion 1c of the halogen lamp manufactured as described above by a normal low pressure chemical vapor deposition method. Are alternately laminated to form a visible light transmitting infrared reflecting film 10, which has a luminous efficiency of 30 compared to a case where no visible light transmitting infrared reflecting film is formed.
% Can be improved.

In the above embodiment, the inflated portion 1
Although the description has been given of the case of the halogen bulb including the arc tube 1 having the b and the reduced diameter portion 1c, the halogen lamp without the reduced diameter portion 1c, that is, the inflated portion 1b and the crushed sealing portion 1d are directly connected to each other, The same effect as described above can be obtained.

Further, in the above embodiment, the case where the arc tube 1 having the spheroidal inflated portion 1b is used has been described. Similar effects can be obtained.

Further, in the above embodiment, the rated voltage 1
Although the description has been given of the case of the halogen lamp of 2V, the present invention is not limited to this. For example, the rated voltage is 6V or 24V.
The same effects as described above can be obtained by applying the manufacturing method of the present invention to a small-sized halogen bulb such as the above, or a bulb such as a high-intensity discharge lamp such as a metal halide lamp sealed at one end.

[0036]

As described above, according to the present invention, since the shape of the arc tube can be suppressed from being distorted, it is possible to prevent the commercial value from being reduced, and the thickness of the arc tube varies. It is possible to provide a low-cost method for manufacturing a bulb, which can suppress the occurrence of cracks and prevent the arc tube from being damaged.

[Brief description of the drawings]

FIG. 1 is a front view of a one-end sealed halogen lamp manufactured using a manufacturing method according to an embodiment of the present invention.

FIG. 2 is a side view of the halogen bulb.

FIG. 3 is a diagram illustrating a manufacturing method according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating a manufacturing method according to an embodiment of the present invention.

FIG. 5 is a diagram illustrating a manufacturing method according to an embodiment of the present invention.

FIG. 6 illustrates a manufacturing method according to an embodiment of the present invention.

FIG. 7 is a front view of a halogen bulb manufactured using the manufacturing method according to the embodiment of the present invention and having a visible light transmitting infrared reflecting film provided on an outer surface thereof;

FIG. 8 is a front view of a conventional halogen bulb.

FIG. 9 is a side view of the halogen bulb.

FIG. 10 is a diagram illustrating a conventional method for manufacturing a halogen bulb.

FIG. 11 is a diagram illustrating a conventional method for manufacturing a halogen bulb.

FIG. 12 is a diagram illustrating a conventional method for manufacturing a halogen bulb.

FIG. 13 is a diagram illustrating a conventional method for manufacturing a halogen bulb.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Arc tube 1b Inflated part 1d Crushed sealing part 2 Electrode 5 Exhaust pipe 6 Glass bulb 9 Mold 10 Visible light transmitting infrared reflection film

Claims (4)

[Claims] 1. A method for manufacturing a bulb having an arc tube having an electrode provided therein and having an inflated portion and a crushed sealing portion, wherein the electrode is placed in a bulb having an exhaust pipe connected to one end. After softening the valve in the arranged state, crush-sealing the end of the valve on the side opposite to the exhaust pipe, and then forming an inflated portion while flowing protective gas from the exhaust pipe. A method for producing a tube, characterized by the following. 2. A reduced diameter portion is formed between the inflated portion and the crushed sealing portion simultaneously with the formation of the inflated portion by pressing a mold having a predetermined shape against the valve. The method for producing a tube according to claim 1, wherein 3. When the outer diameter of the valve is d (mm) and the maximum outer diameter of the inflated portion is D (mm), 1 ≦ D /
The method according to claim 1, wherein the relational expression d ≦ 1.8 is satisfied. 4. When the outer diameter of the valve is d (mm) and the minimum outer diameter of the reduced diameter portion is S (mm), 0.5 ≦ S /
4. The method according to claim 2, wherein d ≦ 1 is satisfied.