JPS6155840A - Manufacture of circular fluorescent lamp - Google Patents

Abstract

PURPOSE:To facilitate adoption of a horizontal method for manufacturing a circular fluorescent lamp by fusing stems to the ends of a straight tubular bulb after concave areas are formed on the outer surfaces of the ends of the bulb during the time, before or after a phosphor formed on the inner surface of the bulb is sintered. CONSTITUTION:A straight tubular bulb 11 the inner surface of which is coated with a fluorescent film 12 is sent into a sintering furnace 14 while being rotated and horizontally held on a feeder. The fluorescent film 12 is sintered by heating the bulb 11 to high temperature. Throughout the last stage of the sintering, the ends of the bulb 11 are heated by burner flame to soften the ends and then concave areas 17 and 17 are formed on their outer surface. Next, stems 19 and 19 having electrodes 18 and 18 and held on mount pins 20 and 20 are fused to the ends of the bulb 11. The bulb 11 is sent to the next process of curving while being held horizontally and then curved into a circular form while being softened by heating.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a method for manufacturing an annular fluorescent lamp, and more particularly to a method for manufacturing an annular fluorescent lamp in a process using a straight tube bulb.

L Coarse Δ Skin ゛Generally, the manufacturing of annular fluorescent lamps involves the steps of applying a fluorescent film to the inner circumferential surface of a straight tube bulb, firing the coated fluorescent film, and the opening end of the straight tube bulb. A process of sealing the stem having an electrode in the TIJ After activating the IP, the exhaust process is filled with necessary inert gas, etc., and the finishing process is to attach the cap to the annular valve. In the above bending process, one end of the straight valve is gripped with a chuck, the other end is gripped with claws protruding from the outer periphery of the bending drum, and the bending drum is rotated along the straight valve. This is done by moving. Therefore, in order to perform the bending process with good IJ, recesses are formed on the outer periphery of both ends of the straight pipe valve so that the chuck and the claws of the bending drum can easily grip it. This recess is formed in the following manner using a mold during an integrated production line after stem sealing and before bending.

The process up to the formation of the recesses in conventional annular fluorescent lamp manufacturing will be explained with reference to FIG. 6 (a) to (f). First, as shown in FIG. A straight tube type bulb (1) is prepared, and a fluorescent film (2) is applied to the inner peripheral surface of the straight tube type bulb (1) as shown in (b) of Figure 6. Next, as shown in FIG. 6(c), the straight tube type bulb (1) is supported vertically and rotated while being fed into a firing furnace (not shown) and subjected to fluorescence II.
! 2! (2) is fired. Next, rotate the straight pipe valve (1) vertically and send it to the stem sealing position, and place it inside the lower end of the straight pipe valve (1) as shown in (d) in Figure 6. A stem (5) having an electrode (3) and an exhaust pipe (4) is held in a mounting bin (6) and inserted into a fixed position while being rotated at the same speed as the straight valve (1). Before and after this insertion, insert the bottom (tli1) of the straight pipe valve (1) into the burner flame (
7) to heat the periphery of the stem (5) to form a straight pipe valve (
1) to seal the stem. When the stem is sealed, the unnecessary part below the sealed part of the straight pipe valve (1) is separated and removed by its own weight.

After sealing the stem, the straight pipe valve (1) is sent to the next position while rotating vertically, and the lower end of the straight pipe valve (1) is exposed to the burner flame ( 8) to soften by intensive heating. Then, at the next position, the rotation of the straight pipe valve (1) is stopped, and as shown in Fig. The molds (9) are pressed against each other to form the desired recess (10).

When the stem sealing and recess formation at one end of the straight pipe valve (1) are completed, turn the straight pipe valve (1) upside down and sealing the stem and forming the recess at the other end in the same manner as above. It will be held on.

Further, the straight tube type bulb (1), which has a stem sealed and a recess formed at both ends, is heated and softened while being vertically supported, and sent to a bending position, where it is bent into an annular shape.

(According to the above, the above-mentioned stem sealing and recess formation are performed on an integrated production line, but in the position of recess formation, molds (9) and (9)
), it was necessary to stop the rotation of the straight pipe valve (1), which made it impossible to manufacture continuous valve rotation through the valve, making it difficult to increase the speed of the manufacturing line.

Furthermore, the above-mentioned stem sealing and the formation of a recess using the molds (9) and (9) after sealing must be carried out by vertically supporting the straight pipe type valve (1). The problem is that the lower end of the straight tube valve (1) shakes during transportation, making it difficult to insert the stem accurately and press the mold against the mold, and that the straight tube valve (1) gets heated and softens, especially during bending. When this happens, it stretches too much under its own weight, causing variations in wall thickness and making it more likely to break.

Therefore, recently, in the same way as in the production of straight tube fluorescent lamps, the straight tube bulb (1) is held horizontally, the fluorescent film is fired, the stem is sealed, and
A so-called polysyntal manufacturing method, in which ring-shaped bending and the like are sequentially performed, is attracting attention as a solution to the above-mentioned problems. However, the use of this polycintal method has been difficult to realize due to the manufacturing method of the stem sealing process and the subsequent recess forming process.

The present invention was made in view of the problems associated with the manufacturing of the stem sealing and subsequent recess formation, and as a means to solve these problems, a straight pipe type To provide a manufacturing method in which a gripping recess is formed on the outer periphery of the open end of a straight tube type bulb during, before, or after firing a fluorescent film formed on the inner peripheral surface of the bulb, and then the stem is sealed. .

A method of forming a recess on the outer periphery of the open end of a straight pipe valve before sealing the stem as in the method described above is to rotate the straight pipe valve horizontally and press a roller against the outer periphery of the pulp end to form the recess. The general pulp tube end processing method for forming the tube can be easily applied, which makes it easy to adopt the polysyntal method for manufacturing annular fluorescent lamps. In addition, since the recess is formed when the fluorescent film is fired, or before or after the firing, when the straight tube bulb is heated to a high temperature, heating of the end of the straight tube bulb is necessary to form the recess. can be carried out using less energy.

A specific embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

Figure 1 is a plan view of an integrated manufacturing line in which a straight pipe valve (11) is held horizontally, rotated, and continuously fed in orthogonal directions to perform firing, recess formation, and stem sealing. A conveying body (13) such as a roller conveyor that carries a straight tube bulb (11) whose surface is coated with a fluorescent film (12) in a horizontal direction.
The straight tube bulb (11) is held horizontally and rotated while being fed into a firing furnace (14). In the firing furnace (14), the straight tube type bulb (11) is heated to a high temperature and the fluorescent film (12) is fired. . At the positions before and after this firing is completed, as shown in Figure 2, both ends of the straight tube type valve (11) are heated with a burner flame (15) to soften them, and then the straight tube type valve (11) rotates on its own axis.
As shown in Figures 2 and 3, there are rollers (16
), (16) are rotated in a driven manner or by a motor or the like at the same circumferential speed as the straight pipe valve (11), and are gradually pressed against each other to remove the softened ends of the straight pipe valve (11). Recesses (17), (17) are formed all at once on the outer periphery. Formation of the recesses using the rollers (16), (16) can be carried out while rotating the straight valve (11) and continuously feeding it, so the production line is significantly reduced compared to the conventional method of forming by pressing a mold. This makes it possible to achieve faster speeds. In addition, since the recesses (17), (17) can be formed at both ends of the straight pipe valve (11) at the same time, productivity can be further improved.
Forming a recess by pressing a mold requires a mold that matches the valve size, and the mold also had to be changed when changing the valve size, whereas forming a recess by using rollers (16), (16) Regardless of the change in valve size, one type of roller (16), (16) can be used.

Incidentally, it is not necessary to form the recesses using the rollers (16) and (16), and the recess formation position may be set at the firing position so that the recess formation is performed simultaneously with the firing, or the recess formation may be performed at the firing position before firing. Straight pipe type valve (11)
The recess may be formed during the heating step.

When the straight tube bulb (11) with completed firing and recess formation comes out of the firing furnace (14), a stem (18) having electrodes (18), (18) at both ends of the straight tube bulb (Step 1) is next installed. 19)
, (19) are held by mounting pins (20), (20) and sealed. Now, the procedure for sealing the stem at one end is shown in step 4.
To explain with reference to the figures and Fig. 5, the stem (19) is, for example, a flare type, and the outside diameter of the flared part (21) is almost the same as the outside diameter of the straight pipe type valve (11), which is the same as the so-called conventional product. is used. The exhaust pipe (22), which is integrally connected to this stem (19), is inserted through the mount I pin (20) and held at the tip of the mount pin (20), in the same way as the straight pipe valve (11). The straight pipe valve (11
), and the distal end peripheral edge of the flared portion (21) is joined to the end surface of the straight pipe valve (11). Then, the joint between the two is heated with a burner flame (23) and the peripheral edge of the tip of the flared part (21) is welded to the end of the straight valve (11) to seal the stem. Stem sealing is simultaneously performed on the other part of the tubular valve (11) in the same manner.

The straight pipe valve (11) whose stem has been sealed is held horizontally and sent to the next bending process, where it is heated and softened and then bent into an annular shape.

31 Corridor and Female Exhibition According to the present invention, the problems of the process of sealing the stem and forming a recess, which were conventional bottlenecks in adopting the horizontal method for manufacturing annular fluorescent lamps, have been solved, making it easier to adopt the horizontal method, and making it easier to use the horizontal method. The ability to speed up the production of fluorescent lamps and improve quality can be achieved.

[Brief explanation of drawings]

Fig. 1 is a schematic plan view of a manufacturing line for explaining the present invention in detail, Fig. 2 is an enlarged side view of the firing and recess forming position shown in Fig. 1, and Fig. 3 is taken along line A-A in Fig. 2. FIGS. 4 and 5 are enlarged sectional views of the end of the valve in various operating states in the stem sealing position of FIG. 1. 6th rI! Parts (A) to (F) of J are side views of a bulb at each step for explaining a conventional method of manufacturing an annular fluorescent lamp. (11) - Straight tube bulb, (12) - Fluorescent film, (17
)--Four parts, (18)--Electrode, (19)--
stem. Ruled 1 prisoner

Claims (1)

[Claims] (1) At the time of firing the fluorescent film applied to the inner peripheral surface of the straight tube bulb, or before or after this firing, a recess for holding the bulb is formed on the outer periphery of the open end of the straight tube bulb, and then 1. A method for manufacturing an annular fluorescent lamp, characterized in that a stem having an electrode is sealed at the open end of a tubular bulb.