JPS59138034A - Manufacture of circular fluorescent lamp - Google Patents

Abstract

PURPOSE:To improve thermal balance of the whole bulb circumference while smoothly performing bending at a bending position in order to improve yielding by heating mainly the nonopposing sides of the bulbs in the heating process of bulbs in a pair of two pieces by a gas burner. CONSTITUTION:Gas burners 41, 41 and 42, 42 are arranged on both sides opposing to the stop positions of the bulbs 91 and 92 in the trapezoidal shape and that halves of the burner-chip insides of the gas burners 41, 41 and 42, 42 are unsight constituted so that the nonopposing sides of the bulbs 91 and 92 are mainly heated in a state of stop. As a result, the thermal balance of the opposing-and- nonopposing sides of the bulbs 91 and 92 is improved thus preventing deformation in the alienating direction at the bottom ends of the bulbs 91 and 92. Accordingly, support of positioning the bulbs 91 and 92 through mounting pins 51 and 52 can be performed surely while being able to goodly perform bending in the next position and to remarkably improve yield.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for manufacturing annular fluorescent lamps, and in particular to a method for manufacturing annular fluorescent lamps.
This invention relates to a heating method using a gas burner that is performed prior to bending a set of linear valves into an annular shape using a set of two bending rollers.

[Background technology]

Generally, this type of annular fluorescent lamp is manufactured as shown in FIGS. 1 to 4, for example. That is, at the stop position [■] of the movable body A that rotates intermittently, multiple sets of chucks B, B, each consisting of two chucks attached to the movable body A so as to be openable and closable, are used. The upper ends of the linear valves C1 and C of this set are fixed so that the lower ends are in a free state. The valves C, , C, are gradually heated as they pass through the heating furnace due to the intermittent rotation of the moving body A. Note that this heating furnace has gas burners E, such as radiant burners, on both sides corresponding to the stop positions of valves C, C,.

2 are arranged at El and E,' so that their centers almost coincide. Then, at the final stop position in the heating furnace, valves C,...
C, is heated to the desired softened state.

On the other hand, when the valves C, , C, are moved to position A and stopped, two sets of mounting pins F, , F rise from below the heating furnace to support the lower end of the valve CI+Cv. Then, when the shutter 〇 of the heating furnace is opened, the lower ends of the valves C, , C2 are fixed to the mounting pins F, , F.
, and is transferred to the next position l] while maintaining the supported state. position field], a set of two curved rollers H, H2 act as valves CI.

Move forward toward the movement trajectory of C7 and curve low -) H,
,H.

Valve C, with a char (not shown) attached to
, C, grip the gripping recess formed at the lower end. At the same time, the mount pins F, F, descend and return to position CII]. In this state, the curved rollers H1, Hz roll upward, thereby simultaneously bending the insides of the valves C, , C into an annular shape.

Thereafter, an annular fluorescent lamp is manufactured through operations such as removing impurity gas within the bulb, activating the electron radioactive material supported on the electrodes, filling with mercury, and filling with inert gas.

By the way, the two sets of valves C,,C, are connected to the gas burners, B, and E, arranged on both sides corresponding to the stop positions of the valves C,,O, in the heating furnace. The entire circumferential surface of the valves O, C
, the opposing circumferential surfaces CIt1. As a result of C2 (2) being further heated by radiant heat, the temperature of the bulb becomes higher than that of the circumferential surface on the non-opposing side.For this reason, the elongation rate due to thermal expansion of the circumferential surface on the opposing side of bulbs C, , C, is large. As a result, the lower ends of the valves C, C2 are deformed in the direction of separation along the movement locus, as shown by the dotted line in FIG.

Such deformation is likely to occur in annular fluorescent lamps that have a small ring diameter, such as FCL20.22, or a large ring diameter, such as FOL40. This is because the heating temperature of the heating furnace is set high in FOL20.22 in order to improve the formability with the curved roller, and in FCL40 the expanded length of the valve is extremely long compared to FCL20.22. for,
This is due to the ease with which the lower end of the valve stretches.

However, if the lower ends of the valves C, , C are deformed so as to separate from each other, the mount pins F,.

The positioning and support of the valves C, , C, by F2 becomes inaccurate, and it becomes difficult to properly perform the bending at the low 5H, Hz position. For example, curved roller H+,
Because the lower ends (gripping recesses) of the valves C, C, cannot be reliably supported by the Hz chuck, the curved roller
Even though yH,,H, increases during transfer, valves C,,C, are not bent at all, or valves C,,C2 are bent at a bending loaf of H+,' Hz. If the valves C, , C, are accommodated eccentrically in the groove, even if the valves C, , C, are bent into an annular shape, the appearance will be significantly impaired and the yield will be significantly reduced.

[Disclosure of the invention]

Therefore, an object of the present invention is to prevent the lower ends of the valves from being deformed in directions opposite to each other even when a set of two linear valves is heated in a heating furnace, and to prevent bending mistakes caused by the bending rollers and bending. The objective is to significantly reduce the number of defects.

The feature of the present invention is that the upper ends of a set of two linear valves are fixed to a moving body that rotates intermittently so that the lower ends are free, and gas burners are installed on both sides corresponding to the stop position. In the process of heating the two sets of bulbs with the gas burner, the bulbs are heated to a softened state in a heating furnace and simultaneously bent into an annular shape using a set of two curved loaves. The main purpose is to heat the non-opposed side of the bulb.

According to this invention, a set of two valves is heated and softened in a heating furnace, and in particular, since the non-opposed sides of the valves are heated by the gas burner, the entire valve is heated by mutual heating by radiant heat on the opposite sides of the valves. The surrounding heat balance is improved.

For this reason, the two sets of valves are no longer deformed in directions away from each other, and bending at the bending position can be smoothly performed, and the yield can be significantly improved.

[BEST MODE 3 FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to FIGS. 5 to 9.

In the figure, reference numeral 1 denotes a moving body that rotates intermittently, and a plurality of sets of two chucks 2+ and 2=, which are configured to be openable and closable, are disposed on the periphery of the moving body or on an arm extending from the periphery.・In addition, Chuck 2. , 2. For example, the center distance of
80mm, the pitch between adjacent chucks is 250~
Each is set to 300 throats. And Chuck 2. , L are provided with heating furnaces 3 at predetermined portions on both sides of their movement loci. This heating furnace 3 has a chuck 2. ．．
Gas burners 4. on both sides corresponding to the stop positions of 22. ,4.
and 4. ,4. are arranged in a figure eight shape as shown in FIGS. 8 and 9. Gas burner 4. ，
4□ and 41, 4. A rectangular radiant burner is suitable for the burner, and the center distance at the upper part is set to, for example, 180 mm, which is the same as that between the two chucks 2+, 2+, and the center distance at the lower part is set to about 190 to 200 mm.

In particular, gas burner 4. ,4. and 41142 burner tips 4. a, 4. a and 4□ (2+4212), almost half of the nozzles inside are blind (the shaded area in Figure 9).This type of gas burner structure is used not only for position CIO, but also for the entire heating furnace. On the other hand, the bottom of the heating furnace 3, especially the position [■]
An opening is formed in the bottom of the mount pin 5. ,5. is installed. This mount pin5. , 5s rises at position [■], maintains that state and moves to position [■], and after stopping, descends and returns to position []I) in synchronization with the moving body 1. The opening at the exit of the heating furnace 3 is closed by a shutter 6.6, and is configured to be opened prior to rotation of the moving body 1.
(2) A bending device 7 is provided, and is composed of two bending rollers 80, 8□. This curved lower 8. , 8. are each a pair of divided rollers 8□4゜8
1b and 82a+8□b, and chuck 2. ．． 2. After moving forward toward the movement trajectory, it rolls and rises, and then the divided rollers 81a, 81b and 8°a, 82b are released and descend.

At position [I] of this manufacturing apparatus, a set of two straight pulp tubes 9. ．． 9. A pair of upper ends of
゛Chuck 21.2. Fix it so that the bottom end is free. The exhaust pipe extending from the upper end of the pulp is connected to the exhaust (not shown). And pulp 9.
,9. Exhaust the air inside. When the moving body 1 rotates intermittently and stops at the next position, the pulp 91.9. The interior is filled with nitrogen gas at a pressure of about 1 atm.

Pulp9. ,,9. is gradually heated as it passes through the heating furnace 3, and is finally heated and softened to an appropriate state at position [II]. In particular, in position CI[], the pulp 92, 9□ has its non-opposed side facing the gas burner 4. ．． 4. and 4. ,4. is heated. For this purpose, pulp 9. ,9. The temperature of the opposing surfaces 9□4, 9□4 no longer increases excessively due to radiant heat, and the thermal balance around the entire pulp is improved. Therefore, pulp 9
．． , 9.0 It is possible to prevent deformation in the direction of separation. In this state, mount pin 5. ．． 5° rises, pulp 9. ,9. Position and support the lower end of. Next, when the shutter 6.6 is opened, the moving body l and the mount pin 5+
, 5i rotates intermittently in synchronization and stops at position [■]. At the same time, the shutter 6.6 is closed. Next, the bending rollers 81 and 82 move the pulp 9. ,9. the lower end (the concave part for gripping) of the curved roller s,
, 82 is gripped by a handle (not shown). In this state, mount pin 5. ,5. falls and returns to position CIO. On the other hand, Kusei Low'
81+81 rises while rolling. This makes the pulp 9. ,9. is simultaneously bent into a ring shape. After bending, the dividing roller 81a.

8□b, 8□4, 8□b are opened and lowered. Thereafter, an annular fluorescent lamp is manufactured by a conventional method.

According to this example, pulp 9. ．． 9. Gas burners 4 on both sides corresponding to the stop position. ．． 4. and 42, 41 are arranged in a V-shape, and gas burners 4. .

41 and 4□, 4. Burner tip 4. a, 4. a and 42a.

Since the inner half of the 4°4 is designed blind, for example in the standstill position CII), the pulp 9. .

9, the non-opposing side is mainly heated. As a result, pulp 9. ,9. Thermal parannu on the opposing side and non-opposing side has been improved, and Palpub 91. Deformation of the lower end of L in the direction of separation can be prevented. Therefore, the pulp by mounting pin 5.15, 9. ,9. positioning and support can be performed reliably, bending at the next position can be performed satisfactorily, and the yield can also be significantly improved.

In particular, this heating method is suitable when using soda glass or low-lead glass with a lead content of less than 10% by weight, for example, about 5% by weight, as the bulbs 91, 9□, but it can also be used for lead glass. It is fully applicable.

In addition, in the present invention, a gas burner having a conventional structure other than the illustrated structure can be used to mainly heat the non-opposing sides of the two-valve set.

Further, the gas burners can be arranged in parallel as well as in a square shape.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing an outline of a conventional annular fluorescent lamp manufacturing apparatus, Fig. 2 is a cross-sectional view of the main part of a heating furnace, Fig. 3 is a cross-sectional view of Fig. 2, and Fig. 4 is a cross-sectional view of a heating furnace. 5 is a plan view schematically showing an apparatus for manufacturing an annular fluorescent lamp according to the method of the present invention, FIG. 6 is a sectional view of the main part of the heating furnace, and FIG. 7 is a cross-sectional view of FIG. 6. 8 is a side sectional view of FIG. 7, and FIG. 9 is a side sectional view of FIG. 8 without the valve. In the figure, 1 is a moving body, 3 is a heating furnace, 42, 4□ is a gas burner, 81. L is a curved roller; 9. ,9. is a valve, 91
+2.92a is the opposite side. Figure 1 Figure 2 Figure 5 [I] Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] A heating furnace in which the upper ends of a set of two linear valves are fixed to a moving body that rotates intermittently so that the lower ends are free, and gas burners are arranged on both sides corresponding to the stop position. When the bulbs are heated and softened by heating and simultaneously bent into an annular shape by a set of two bending rollers, the main toss lever/L' A method for manufacturing an annular fluorescent lamp, characterized in that the non-opposing side of the lamp is heated.