JPH0684462A - Manufacture of bulb stem - Google Patents

Abstract

PURPOSE:To prevent a bulb stem from being cracked or broken by glass distortion. CONSTITUTION:During the manufacture of a stem, a stem-distortion removing burner 8 is disposed at an angle of 45 to 90 deg. to the direction of a stem molding burner, i.e., a pincher 9 and after the stem is molded the distortion removing burner is applied to the middle portion between the highest and lowest temperature portions of the stem. The stem molded at high temperatures is therefore uniformly cooled and no excessive distortion remains.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing various tube stems such as fluorescent lamps and light bulbs.

[0002]

2. Description of the Related Art The bulbs of fluorescent lamps and electric bulbs of this kind are made of glass bulbs, and the ends of the bulbs usually have a lead wire for leading out an electrode and an exhaust pipe for exhausting the inside of the bulb. Is sealed. For example, FIG. 4 shows a fluorescent lamp 1.
FIG. 3 is a cross-sectional view showing the structure of a sealed portion of the fluorescent lamp 1 with a stem 5 having a pair of electrode lead wires 3 and 3 and an exhaust pipe 4 sealed at the end of the glass bulb 2. Make up the envelope. As shown in FIG. 5, the stem 5 penetrates the pair of electrode lead wires 3 and 3 at the inner end of a flare 6 whose one end is close to the inner diameter of the valve 2 and has a scat shape. It is a structure in which the exhaust pipe is led out while being pinched.

As shown in FIG. 6, in the stem 5 having such a structure, molding burners 7 are arranged on both sides of the inner end of the glass flare 6, and the pin burner is heated and melted at a temperature higher than the softening temperature. It is crushed by-and is fused with the electrode lead wires 3 and 3, and subsequently, as shown in FIG. 7, the strain is removed by the strain relief burner 8 similarly arranged.

[0004]

By the way, when the fluorescent lamp 1 is manufactured by sealing the stem 5 manufactured as described above to the end of the glass bulb 2, a problem that cracks due to glass distortion occur in the stem 5 part. was there. As a result, problems often occur during the fluorescent lamp manufacturing process and during the market sales.

Therefore, conventionally, in order to remove the distortion,
Part of it is also to provide a dedicated conveyor. However, providing the dedicated conveyor in this way requires not only the equipment and the utility, but is uneconomical, and there is a problem in that the cost is high because of the layout and the number of man-hours. In particular, in recent years, there has been a trend toward faster lamp manufacturing, and strain removal tends to become more uncertain, and there has been a demand for elimination of cracks due to glass strain in the stem portion.

Therefore, the present invention has been made in view of the above, and even if it is applied to a high-speed lamp manufacturing line without providing a dedicated conveyor, the amount of glass strain in the stem portion is sufficiently reduced and cracks are generated. It is an object of the present invention to provide a method for manufacturing a stem for a tube, which is capable of eradicating

[0007]

In order to achieve the above object, the present invention is directed to a stem forming burner at 45 ° to 9 °.
A stem strain removing burner is arranged at a position of 0 ° to remove strain.

[0008]

When the stem is molded, the flare is heated and melted by the stem molding burner and pinched and sealed. Although it cools rapidly after the pinch and drops below the strain point, the temperature is the lowest in the direction orthogonal to the molding burner and the highest in the surface facing the molding burner. Therefore, there is a difference in cooling temperature, and if the strain relief burner is applied from the same direction as the stem forming burner as in the conventional case, the difference in cooling rate of the highest temperature part can be reduced, but the cooling rate of both is reduced. Difference remains, and thus a large distortion remains. According to the present invention, the strain removing burner is placed in the range from the middle of the highest temperature part and the lowest temperature part to the lowest temperature part, the temperature of the lowest temperature part rises, and the cooling of the highest temperature part and the lowest temperature part occurs. Since the speeds are averaged, the amount of strain is reduced as much as possible.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a plan view of a stem machine including a turntable according to an embodiment of the present invention. Material supply, b. First heating, c. First molding, d. Second heating, e. Second molding,
f. Third heating, g. Third molding, h. Cooling, i. Distortion removal,
j. It consists of steps such as cooling, and these steps themselves are the same as conventional ones. That is, the flare 6 supplied in the material supplying step a is subjected to the above processing steps b to f, and finally in the forming step g, as shown in FIG. Fully heated and softened with a pincher (not shown)
The inner end is pressed and shaped by the pair of electrode lead wires 3, 3
Alternatively, the fused portion of the exhaust pipe 4 is aligned in a predetermined shape, and this is pinch-sealed.

2 and 3 are the main steps of the present invention i
4A and 4B are a side view and a top view of the burner arrangement in the strain removing step of FIG.
They are arranged in a direction inclined at an angle of 90 ° to 90 °. Therefore, the flame from the strain removing burner 8 is applied not to the central portion of the pinch seal portion of the flare 6 but to the positions shifted to both side surfaces of the lowest temperature.

[0011]

As described above, according to the present invention, the strain relief burner 8 is 45 ° to 9 ° with respect to the molding burner 7, respectively.
Since the flame from the strain relief burner 8 is arranged in a direction inclined by 0 °, it is applied not to the central portion of the pinch seal of the flare 6 but to the positions shifted to both sides of the minimum temperature, so that the stem The amount of distortion is reduced as much as possible. Therefore, even if it is applied to a high-speed lamp manufacturing line without providing a dedicated conveyor or the like, the amount of glass strain in the stem portion is sufficiently reduced,
Eradicates cracks in fluorescent lamps. It is needless to say that the present invention can be used not only for erasing cracks of a fluorescent lamp but also for manufacturing a bulb stem having a similar configuration, and can obtain similar operational effects.

[Brief description of drawings]

FIG. 1 is a plan view of a stem manufacturing apparatus to which a tube stem of the present invention is applied.

FIG. 2 is a side view of a strain removing burner portion in a strain removing process of the present invention.

FIG. 3 is a top view of a strain removal burner portion in a strain removal process of the present invention.

FIG. 4 is a sectional view of a sealing portion of a fluorescent lamp to which the bulb stem of the present invention is applied.

FIG. 5 is a cross-sectional view of the tube stem of the present invention.

FIG. 6 is a side view illustrating a molding step in the stem manufacturing process.

FIG. 7 is a side view illustrating a strain removing step in the stem manufacturing process.

[Explanation of symbols]

 5 Stem for tube 6 Flare 7 Molding burner 8 Strain removing burner

Claims (1)

[Claims] 1. The stem forming burner is at an angle of 45.degree.
A method for producing a stem for a tube, comprising removing a strain by disposing a stem strain removing burner at a position of 90 °.