JPS61126735A - Method of sealing fluorescent lamp - Google Patents

Abstract

PURPOSE:To achieve improved sealing of a fluorescent lamp by promoting good connection between the flare and a thick section by forming it before the flare is brought into contact with the bulb end so as to prevent rapid cooling of the thick section. CONSTITUTION:In order to prevent a thick section 50 from being cooled before a flare 35 is brought into contact with the section 50 by moving down a mount holder 37, the holder 37 is vertically reciprocated so that thermal energy from a burner 40 is stored in the section 50 while the flare 35 is apart from the section 50 and heat is transmitted to the flare 35 while the flare 35 touches the section 50. Next, the burner 40 is used to heat the section 50 while the flare 35 is fixed to the section 50 to fuse these parts thereby forming a thick sealing area 51. While the thick sealing area 51 is still softened, the area 51 is covered by a mold 60 and compressed air is sent into the bulb 30 to expands the area 51 toward the inner surface of a mold 60 thereby forming a nodal section 70.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for sealing stem glass in a fluorescent lamp into pulp.

[Technical background of the invention]

Normally, to manufacture an annular fluorescent lamp, a stem with electrodes is sealed at both ends of a straight glass bulb whose inner surface is coated with a fluorescent coating, and a mold is used to seal the stem into a joint. Then, the glass bulb is heated and softened by gripping the joints to form a curve. The above-mentioned joints serve as gripping hooks when bent into an annular shape.

By the way, in manufacturing the above-mentioned annular fluorescent rung, the stem must be sealed to the end of the straight glass bulb before the knot is formed in the sealing part, but the conventional stem sealing method is The following two methods were used.

One of them is the so-called curlet method shown in FIG. 7 (4) (B), in which a stem glass is inserted several tens of meters from the end of the glass bulb 1 into the center along the axial direction. 2 is inserted by a mount holder 3, and the outer periphery of the pulp 1 facing the flare part 4 of the stem glass 2 is heated and softened by a sealing burner 5. When heated and softened, the diameter of the pulp in the heated part is reduced based on the properties of the glass tube, and the pulp is melted and sealed to the flared part 4. At this time, the curled part 6 located below the flared part 4 becomes a sealed part due to its own weight. It is cut off by falling from the ground. Although this curlet method has a simple sealing process, it has the disadvantage that the curled portion 6 is cut off and discarded, resulting in a large loss of glass material.

Another known method is the so-called pat-seal method shown in FIGS. 8cA and 8B.

In this case, the end of the glass bulb 1 is pre-diametered with an end 7 ohm to reduce its diameter.
0, attach the flare part 4 of the stem glass 2 to the mount holder 3.
The burner 21 makes contact with the burner 21 from the outside.
It can be heated and softened by the method of sealing,
Although this method does not cause material loss, it has the disadvantage of increasing the number of work steps because it requires end forming in advance.

Therefore, all of the above-mentioned methods have the disadvantage of causing material loss or an increase in processing steps.

For these reasons, the applicant has decided to
We proposed the method disclosed in ``K.740 Newsletter''. In this method, when sealing a stem glass in a glass bulb, the flare part of the stem glass is positioned slightly closer to the center from the open end of the glass bulb, and the burner is further positioned closer to the center of the pulp than the flare part. When the pulp is heated by heating the pulp, the pulp is softened and reduced in diameter, and when the burner is sequentially moved toward the open end, the pulp and the flared portion are melted and sealed, and a meat reservoir is created. It is.

This method has the advantage that unlike the curlet method, there is no loss of the glass bulb, and there is no need for end forming in advance, which is required in the pad seal method, so the number of work steps can be reduced.

[Problems with background technology]

However, in the method described in the above-mentioned publication, a burner is used to heat the inner part of the pulp closer to the center than the flared part.
When the burner is moved toward the open end side, the diameter of the pulp is reduced at the position where the burner is located, and as this diameter reduction progresses, it comes into contact with the flared portion of the stem glass and welds the two together. However, at the stage when the reduced diameter part contacts the flared part, the temperature of the flared part is not yet sufficient, and sufficient thermal energy is not stored in the reduced diameter part, so the fit between the flared part and the reduced diameter part is low. There was a problem that some products were found to have poor melt sealing performance.

[Purpose of the invention]

The present invention has been made based on the above circumstances, and its purpose is to seal a fluorescent lamp in which the flare portion and the glass bulb can be reliably melted and sealed, thereby making it possible to improve the yield9. The aim is to provide a method to stop this.

[Summary of the invention]

That is, in the present invention, the flared portion of the stem glass, which has been cut to a predetermined length in advance, is inserted so that the straight shape is located slightly closer to the center than the open end of the lath pulp, and the flared portion is positioned closer to the open end than the flared portion. The glass bulb is heated and softened with a burner to reduce its diameter, and the burner is moved to the open end side of the pulp to reduce the diameter of the pulp and form a meat pocket, and then the flared part of the stem glass is inserted into the above-mentioned meat pocket. 1. Since the Lasno Norupu is cut to a predetermined length in advance, there is no material loss of the pulp, and the diameter is reduced when the pulp is heated and softened. Since the stem glass is sealed, the open end side of the pulp is melted and the open end of the pulp is melted while sealing the stem glass. It is characterized by forming a diameter-reduced meat reservoir at the end, and using the high heat energy stored in this meat reservoir to promote familiarity with the flare part and sealing the flare part.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to an annular fluorescent lamp shown in FIGS. 1 to 6.

1 to 6 are cross-sectional views shown based on the order of steps.

In the figure, reference numeral 30 denotes a straight glass bulb, which is cut in advance to a size slightly longer than the lamp length, and has a phosphor coating 31 applied to its inner surface. Note that the slightly longer dimension described above approximately corresponds to L in FIG.

32 is a stem glass, and the electrode 33 is connected to a lead wire 34.
It is supported by 34. The flare portion 35 of the stem glass 32 has a smaller diameter than the inner diameter of the glass bulb 30. Note that 36 in FIGS. 5 and 6 is an exhaust pipe.

Such a stem glass 32 is supported by a mount holder 37 and inserted into the end of the glass bulb 3Q. In this case, as shown in FIG.
It is located inside the opening edge 30h of 0 toward the pulp center by a dimension t.

The burner 40 shown in FIG. 2 is a ring burner, and has an annular shape that surrounds the outside of the pulp 30, and has flame holes 41 on the inner peripheral surface at equal intervals in the circumferential direction. ·have. The burner 40 is movable along the axial direction of the pulp 30 by an appropriate drive means (not shown).
When the setting is completed as shown in the figure, it is moved to the position shown in FIG. The burner position in Figure 2 is flame hole 4.
1... is a position that is closer to the center than the opening edge 30a of the pulp 30, and this dimension is smaller than the above t, and the flame hole 41... is closer to the center than the opening edge 30a of the pulp 30. This is the location located at the opening end 30  Note that this dimension is an important dimension for determining the wall thickness of the meat temperature portion, which will be described later, and is preferably about 4±2+m, although it varies depending on the reed, pulp diameter, and flare diameter. The burner 40 in the position shown in FIG. 2 initially preheats the pulp wall with low heat and then heats the tube wall with high heat to soften it and heat it until the tube wall is slightly reduced in diameter as shown in FIG. Note that a glass tube has the property of being deformed by reducing its diameter (squeezing) when the tube wall is heated and softened.

When the diameter of the pipe wall closer to the pulp opening end than the flare portion 35 is reduced in this way, the burner 40 is slowly moved toward the opening end. As a result of this movement, the open end of the pulp 30 begins to melt, and shrinkage in diameter and axial direction progresses, producing a pulp pocket 50 as shown in FIG. Heating by the burner 40 is continued until the inner diameter of this meat pocket 50 becomes smaller than the outer diameter of the flare portion 35.

Next, as shown by the arrow in FIG.
is lowered to bring the flare part 35 into contact with the fat pocket part 50. This contact causes the flared portion 35 to adhere to the thickened portion 50. During this adhesion, since the heat capacity of the flesh-warming portion 50 is large, heat is conducted to the flared portion 35 to promote a rise in temperature of the flared portion 35, promoting so-called conformation.

However, during the above-mentioned contact, the heat of the meat pocket 5o escapes to the flare part 35 and the meat warm part 5o cools down), which may cause the female part to become loose.To prevent this, the mount holder 37 is moved upward and downward. The flare portion 35 is brought into contact with and separated from the meat warming portion 50 by reciprocating a plurality of times. As a result of this contact and separation, the heat energy from the burner 40 is stored in the meat pocket 50 when they are apart, and the heat stored in the meat pocket 50 when they are in contact is transmitted to the flare portion 35 and Since the temperature is raised, the flare portion 35 and the meat warming portion 50 are facilitated to become acquainted with each other. After repeating the above contact, the flare portion 35 is attached to the meat pocket 50 and this is attached to the burner 4.
When heated at 0, both melt and seal together.

In this sealed state, the sealed portion becomes a thick portion 5 as shown in FIG. 5 due to the flesh temperature portion 50.

When the thick portion 51 as shown in FIG. 5 is obtained, the flame of the burner 40 is made low and the burner 40 is moved downward as shown in FIG. Next, a mold 60 is set while the thick portion 5 is still in a softened state. The mold 60 is of a split type that is divided into left and right parts as shown in the figure, and is brought into contact with each other by moving in the directions of arrows a and b to cover the sealing part. At this time, the mount holder 37 is released downward in the figure.

After covering the sealing portion with the mold 60, for example, pressurized air is blown into the pulp 30 to increase the pressure within the pulp relative to the external pressure. Then, the sealing portion, which is still in a softened state, expands into the inner surface of the mold 60. As a result, a knot 70 matching the inner shape of the mold 60 is formed as shown in FIG. Since the glass material of the thick portion 51 is stretched during the inward expansion, the thickness of the joint portion 70 becomes approximately equal.

According to this method, since the straight glass bulb 30 is cut in advance to a predetermined length (approximately equal to the product length + 2L), there is no waste of glass material as in the conventional curlet method (Fig. 7). There is no need for this, and material costs are low.

Further, since the pulp 30 is sealed to the flare portion 35 by utilizing the property of being heated and softened by the burner 40 from the outer periphery and being reduced in diameter, the conventional pad seal method (No. 8
There is no need to perform end forming in advance as shown in Figure), thus reducing the number of steps.

As shown in FIGS. 3 and 4, a meat pocket 50 is made in advance at the end of the pulp 30, and the meat pocket 50
In addition, since the flared portion 35 inserted into the pulp 30 is brought into contact with the pulp 30, the meat reservoir portion 50 has a large heat capacity, and the thermal energy is conducted to the flared portion 35 and the two become compatible. promoted.

In particular, when the flare portion 35 is brought into contact with and separated from the meat accumulation portion 50 multiple times, the fitting becomes even better.

Therefore, sealing defects can be prevented and yields can be improved.

In addition, in the above embodiment, the process up to the step of forming the joint part 70 at the end was premised on the case of manufacturing a ring-shaped fluorescent lamp, but the present invention is not limited to this, and the present invention is not limited to this. It is also possible to implement the method.

〔Effect of the invention〕

As described above, according to the method of the present invention, a meat pocket is formed before the flare part is brought into contact with the pulp end, so the heat capacity of this meat pocket is large, so that the flare part can be brought into contact with the pulp end. When many parts are brought into contact with each other, there is no extreme rapid cooling of the thickening part, and as a result, the fitting of the thickening part and the flare part is promoted, and good sealing is achieved. Therefore, sealing defects are eliminated and yield can be improved.

[Brief explanation of drawings]

FIGS. 1 to 6 show an embodiment of the present invention, and are sectional views illustrating the steps of each process in the case of an annular fluorescent rung. Figure 7 (A) (B) and Figure 8 (A) (
B) explains the conventional method, and Figure 7 cA) (
B) is an explanatory diagram of the car red method, and FIG. 8 (B) is an explanatory diagram of the pad seal method. J O-...Glass bulb, 30h...Open end, 32
... Stem glass, 33... Electrode, 35... Flare part, 40... Burner, 50... Meat reservoir part, 51...
...Thick wall part, 60...type, 70...knot part. Applicant's Patent Attorney Takehiko Suzue Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7' (A) Figure 8 (A) Nu (B) Figure (B)

Claims (2)

[Claims] (1) Insert a stem glass into the end of a straight glass bulb that has been cut to a predetermined length, position the flared part of the stem glass closer to the center than the open end of the glass bulb, and A burner heats a position closer to the open end than the flared part to reduce the diameter of the valve, and the burner is sequentially moved toward the open end to melt the open end and form a meat pocket at the open end. A method for sealing a fluorescent lamp, characterized in that the flared portion of the stem glass is then brought into contact with the bulge and welded, thereby sealing the stem glass to the glass bulb. (2) When welding the flared portion of the stem glass to the fleshy pocket formed at the open end of the pulp, the flared portion of the stem glass is brought into contact with and separated from the fleshy pocket several times in advance to separate the flared portion and the fleshy pocket. A method for sealing a fluorescent lamp according to claim (1), characterized in that the sealing method is adapted to improve familiarity.