JP2506646B2 - Fluorescent lamp manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a fluorescent lamp, and more particularly to a method for manufacturing a fluorescent lamp in which the mercury vapor pressure in a tube is controlled by an amalgam-forming substance.

Fluorescent lamp device having a structure in which a U-shaped or double-U-shaped fluorescent lamp is integrated in a sealed outer tube together with a ballast, a lighting tube, and a bulb base cap in order to save power for an incandescent light bulb. Has become widespread.

However, in the fluorescent lamp device having such a structure, the ambient temperature of the fluorescent lamp is significantly higher than the optimum temperature of 20 to 25 ° C. due to the structure in which the fluorescent lamp is sealed in the outer tube. In such a case, it is known to use an amalgam-forming substance having a vapor pressure lower than that of pure mercury in order to suppress an excessive rise in mercury vapor pressure and prevent a decrease in luminous efficiency.
As the same material, pure In or In-based alloy such as BiIn, I
nSnPb and the like are considered to be optimal, and are now commercialized and widely used. Each of these amalgam formers has its own optimum temperature for mercury vapor pressure, which is usually near the melting point of the metal or alloy. Therefore, the place where the amalgam forming substance is provided in the glass tube depends on the type of the substance. It may be provided on the stem while avoiding the discharge space, but in general, from the viewpoint of manufacturing, the inside of the glass thin tube communicating with the inside of the glass tube is selected. Since the lighting direction of the lamp is mostly on the base, the amalgam forming substance is held on the upper surface of the glass thin tube through a glass blank tube of a specified length as a spacer in the glass thin tube, and from the electrode bright point during lamp lighting. The radiant heat of the amalgam causes the temperature of the amalgam to reach the temperature most suitable for its action.

FIG. 3 is an enlarged cross-sectional view of the side having the amalgam forming substance 9 among the pair of electrodes provided at both ends of the glass tube 1, and the electrode coil 5 is held by the internal lead wire 6. The other end of the glass thin tube 10 whose one end is sealed is an opening 7 that faces the inside of the glass tube 1. A spherical amalgam forming substance 9 is located in the glass capillary 10 via a spacer 8.

Problems to be Solved by the Invention By the way, indium alloys are easily melted,
Easily adheres to the glass surface. When the lamp is turned on, the amalgam-forming substance may remain on the upper surface of the spacer 8 while being attached to the inner surface of the top of the glass capillary 10 as shown in FIG. In such a state, the distance between the amalgam forming substance 9 and the electrode bright spot becomes longer than the initial distance defined by the spacer 8, and the amalgam forming substance 9 is left at a temperature much lower than the optimum temperature and the lamp is left. Efficiency is significantly reduced.

The present invention has been made in order to solve such problems, and provides a method for manufacturing a fluorescent lamp capable of sufficiently exhibiting the effect of an amalgam-forming substance and maintaining high luminous efficiency. is there.

Means for Solving Problems The inventors have found that the adhesive force of an amalgam-forming substance to the inner surface of a glass capillary tube is greatly affected by the molten state of the substance in the fluorescent lamp manufacturing process, and completed the present invention. Came to do.

That is, the method for manufacturing a fluorescent lamp of the present invention is provided at one end of a glass tube, and the opening of the glass capillary having a tip opening in which an indium-based amalgam forming substance is inserted is directed upward, Hold the glass tube, heat and seal the glass capillary, then cool the sealed portion of the glass capillary to a temperature below the melting point of the amalgam-forming substance, and then reverse the vertical position of the glass tube After that, the glass tube is heated and evacuated, and mercury is enclosed in the glass tube to obtain a fluorescent lamp.

When the glass tube is heated and sealed, and then the glass tube is turned upside down as it is, the amalgam-forming substance touches the inner surface of the still hot glass tube and is instantly melted to adhere to the inner surface. In this case, the adhesion is very strong, and since this melting is usually performed in air, the material oxidizes and loses the surface tension, so even if this substance is cooled to room temperature again, it is unlikely to become spherical. , Often remains attached to the inner surface of the glass capillary.

However, after sealing the glass capillary, this sealing part is cooled below the melting of the amalgam-forming substance, and then the glass tube is turned upside down, the amalgam-forming substance does not melt and maintains its original shape. It only melts in the heating and exhausting process. In this case, in a non-oxidizing atmosphere, since the temperature of the amalgam forming substance rises simultaneously with the inner surface of the glass capillary in contact with the amalgam forming substance and the melting of the substance gradually progresses, there is no oxidation of the material, The surface tension is not lost.
Therefore, after the fluorescent lamp is completed, when the temperature falls to room temperature again, the amalgam-forming substance becomes spherical, does not adhere to the inner surface of the glass capillary, and fully exhibits its original function, thus the lamp exhibits high luminous efficiency. .

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

In FIG. 1 (a), a glass empty tube having an outer diameter of 2.6 mm and a length of 11 mm is first inserted as a spacer 8 into a glass capillary tube 10 having an inner diameter of 3.3 mm at the tip opening, and then an amalgam forming substance 9 is used. As a pellet, a BiIn alloy pellet having an outer diameter of 2.8 mm, a length of 4 mm and a weight of 180 mg (melting point 110 ° C.) was inserted. After that, as shown in FIG. 1 (b), the vicinity of the pellet is kept in the same direction.
The portion 3 mm above was heated with a chip burner (not shown) to seal the glass capillary 10. After that, the sealed portion was air-cooled in a time schedule such that no strain was generated in the glass thin tube 10, and the temperature of this portion was set to 110 ° C. or lower. Subsequently, as shown in FIG. 1 (c), the vertical position of the glass tube 1 is reversed. In this reversal process, as shown in the figure, the pellets did not melt and maintained their original shape. After that, the usual heating and exhausting process was performed, and finally 6 mg from the other glass capillary into the glass tube 1.
After filling with mercury and 400 Pa of argon gas, the other glass capillary was sealed as shown in FIG. 1 (d) to complete a fluorescent lamp having an amalgam forming substance. The diameter of the double U-shaped glass tube 1 is 15.5 mm, the distance between the electrodes is 280 mm, and the inner surface of the glass tube is a rare-earth fluorescent substance of the three-wavelength emission region that emits light at a color temperature of 2800 K. ^It was applied at a rate of ⁵ .

As usual, this fluorescent lamp was integrated with a diffused / sealed glass outer tube 2 having an outer diameter of 104 mm and a ballast 3 as shown in FIG. 2 to complete a bulb-type fluorescent lamp device. In addition, in FIG. 2, 4 shows a light bulb base.

When this lamp was lit at an ambient temperature of 25 ° C and a total input power of 17 W including ballast loss in the lighting direction on the base, the amalgam forming substance exhibited a predetermined effect and showed a high efficiency of 45 lm / W. . This value is the lamp efficiency of about 41 m / m when the amalgam forming substance adheres to the inner surface of the conventional glass capillary.
This is a significant improvement of 10% compared to W.

In the present invention, the vertical position of the glass tube is inverted after sealing the glass tube for the following reason. That is, in general, the amalgam-forming substance has a melting point of 200 ° C.
Since the following low-melting-point alloys are used, in the heating and exhausting process of a fluorescent lamp that reaches a temperature of 400 ° C. or higher, the glass tube is in the state shown in FIG. 1 (b), that is, with the glass thin tube facing upward. If heating and exhausting are carried out, there is a risk that the amalgam forming substance will melt in the exhaust furnace and fall into the glass tube through the gap between the outer peripheral surface of the spacer and the inner peripheral surface of the glass capillary.

Therefore, in the present invention, in the heating and exhausting step,
In order to retain the amalgam-forming substance on the bottom surface of the sealed portion of the glass capillary, the glass tube is sealed and then the vertical position of the glass tube is reversed.

Further, in the present invention, after sealing the glass thin tube, the sealed portion is cooled to a temperature below the melting point of the amalgam forming substance for the following reason. That is, if the glass tube is turned upside down without going through the cooling step, the amalgam-forming substance is melted by contact with the inner surface of the sealing portion of the glass capillary still hot, so that the same substance The inconvenience of adhering to the inner surface occurs.

However, as in the present invention, when the temperature of the sealed portion of the glass capillary is cooled to a temperature equal to or lower than the melting point of the amalgam forming substance, the glass pipe is turned upside down, and after heating and evacuation, the amalgam forming substance is suspected. When it solidifies, it becomes spherical due to sufficient surface tension, so that it is possible to avoid the inconvenience that the same substance adheres to the inner surface of the glass capillary.

Effects of the Invention As described above, according to the manufacturing method of the present invention, the opening of the glass capillary having a tip opening provided at one end of the glass tube and having an indium-based amalgam forming substance inserted therein is directed upward. So that the glass tube is held, the glass tube is heated and sealed, and then the sealed portion of the glass tube is cooled to a temperature below the melting point of the amalgam-forming substance, and then the glass tube. Since the upper and lower positions of the glass tube were inverted, and then the glass tube was heated and evacuated and mercury was enclosed in the glass tube to obtain a fluorescent lamp, adhesion of the amalgam-forming substance to the inner surface of the glass thin tube can be eliminated. Therefore, it is possible to obtain a fluorescent lamp exhibiting a predetermined luminous efficiency, which is capable of sufficiently exhibiting the original function of the amalgam-forming substance, and also any additional material. There is no need to use additional, and the effect is extremely large.

[Brief description of drawings]

1 (a) to 1 (d) are process diagrams of a method for manufacturing a fluorescent lamp according to an embodiment of the present invention, and FIG. 2 is a front view showing an example of a fluorescent lamp device incorporating the fluorescent lamp. FIG. 3 is a partially enlarged cross-sectional view of a conventional fluorescent lamp, and FIG. 4 is a diagram for explaining inconveniences in a conventional fluorescent lamp manufacturing method. 1 ... Glass tube, 9 ... Amalgam forming substance, 10 ... Glass thin tube.

Claims (1)

(57) [Claims] 1. A glass tube which is provided at one end of a glass tube and in which an indium-based amalgam-forming substance is inserted into the glass tube, the glass tube being held so that the opening thereof faces upward, The thin tube is heated and sealed, then, the sealed portion of the glass thin tube is cooled to a temperature equal to or lower than the melting point of the amalgam-forming substance, and then the vertical position of the glass tube is reversed, and then the glass tube is closed. A method of manufacturing a fluorescent lamp, which comprises heating and exhausting, and enclosing mercury in the glass tube to obtain a fluorescent lamp.