JPS59211937A - Manufacture of circular fluorescent lamp - Google Patents

Abstract

PURPOSE:To reduce the fraction defective of a circular lamp and improve its quality by mixing SO2 in combustion gas at heating and deformation. CONSTITUTION:When a circular fluorescent lamp is obtained by heating and softening a straight-tube-type sealing tube made of soda glass or low lead glass and deforming it annularly, SO2 is mixed, by 30-200cc/11,000Kcal/Nm<3>, in a heating furnace heated to approximately 450 deg.C for the purpose of heating and softening process or in the heating gas in a burner for heating a sealing tube hooking pawl and the Na2SO4 coat, i.e. an SO2 formation product is produced on the surface layers of a sealing tube to be processed and a hooking pawl. When SO2 is mixed, it is recommended that an SO2 nozzle is opened in the gas flow direction at the center of piping at the specific position of a combustion gas supply tube. As a result, the generation of a crack is decreased sharply.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an annular fluorescent lamp, and more particularly to an annular deformation of a glass sealed tube.
J) To provide a method for manufacturing a fluorescent lamp of stable quality by preventing the occurrence of cracks at the portion where the F-ray contacts the sealing portion.

An example of the manufacturing method of a conventional annular fluorescent lamp will be explained with reference to FIGS. 1 and 2.

A locking claw 4 is engaged with a neck portion 3 at one end of a straight sealed tube 1'' made of soda glass or low lead glass, and the neck portion 3 at the other end is supported by a holder 2.

Next, the sealed tube 1 is heated to its softening temperature and deformed into an annular shape as shown in FIG. 2 to obtain an annular fluorescent lamp. In the top view, 5, 6, and 7.8 are lead wires, respectively. In manufacturing such an annular fluorescent lamp, the locking claw 4 and the neck portion 3 are
Cracks occur in the neck portion 3 due to mutual temperature difference and mechanical pressure during attachment, which is a serious cause of deterioration of product quality. Furthermore, even in the parts where the lead wires come into contact with the sealing parts, cracks are unavoidable due to the temperature difference between them.
These have become a serious cause of spontaneous breakage of annular fluorescent lamps.

Therefore, attempts have been made to avoid the occurrence of ceramic by making the locking pawl 4, for example, a ceramic material with low thermal conductivity and high heat retention, but the effectiveness in preventing cracks is insufficient, and rather the ceramic material It has major economic disadvantages such as high price and high maintenance costs, and is therefore impractical.

As a result of repeated consideration in view of such problems, the inventors have hereby found that
When the sealed tube is deformed into an annular shape, So
This invention was achieved by discovering the fact that the occurrence of the above-mentioned cracks is drastically reduced by the presence of Z.

In other words, the present invention can be applied to soda glass or low lead glass.
When obtaining an annular fluorescent lamp by heating and softening a straight sealed tube and deforming it into an annular shape, approximately 4
Add 30 to 200 cc of SOW to the heated gas in a heating furnace heated to 50°C or a heating burner for a sealing tube locking claw.
11,000 Kai/Nm' was added to the surface layer of the sealing tube to be processed and the locking claw.

A method for manufacturing annular fluorescent lamps, characterized in that a Na2SO4 coating of the product is produced.

Generally, coal gas or natural gas is used as combustion gas for heating when manufacturing tubes and the like.

It is known that Sot is included in the components of these combustion gases, albeit in small amounts, and by adding So, for example, S02 products (Na
It is also known that the friction reducing effect of 25O4) produces an effect that can appropriately prevent the occurrence of wrinkles, twists, etc.

The present invention focuses on this fact. Now, FIG. 3 shows the results of measuring the defective rate due to the occurrence of cracks when SO2 was added to the combustion gas during heating and deformation according to the conventional manufacturing method of the annular fluorescent lamp described above.

From the results in the same figure, (1) the amount of So added is 30 (C/11000
It has become clear that below Ka+ll/Nm" (hereinafter simply abbreviated as jin), the defective rate due to crack generation increases significantly; (11) When it exceeds 200 cc, the effect does not increase any further.

That is, the SO mixed into the combustion gas during the heating mentioned above
The appropriate amount is in the range of 30 to 200 kernels.

For example, when about 20 cc of the above-mentioned SO2 is originally present in a component such as coal gas, the effect of the present invention can be substantially obtained by mixing in the amount insufficient to the above range, that is, 30 to 200 cc.

Specifically, when mixing the above-mentioned S Ot, at a specific position of the combustion gas supply piping, add S Ot in the gas flow direction at the center of the piping.
O. It is preferable to open the nozzle. In the gas flow rate range of 1 to 10/, the nozzle diameter is 1.5 to 2.0φ.
It is better to

The present invention can significantly reduce the defect rate of polycyclic lamps simply by mixing SO3 into the combustion gas, and the effect of improving product quality is of great industrial value.

[Brief explanation of the drawing]

1 and 82 are diagrams showing the manufacturing mode of a general ring-shaped rande, and FIG. 3 is a diagram showing the relationship between the amount of SO7 and the defective rate in the present invention. 1...Sealed tube, 2-...Holder, 3...Neck,
4...Latching claw. Agent Masuo Oiwa 1st staff member 6 Figure 2 Gin/Nememi &-me 17

Claims (1)

[Claims] When obtaining a ring-shaped fluorescent lamp by heating and softening a straight sealed tube made of soda glass or low-lead glass and deforming it into an annular shape, a heating furnace heated to about 450°C at the time of heating and softening, and a steel seal are used. Add 30 to 200 cc/11,0OOK of SO2 into the heating gas in the heating burner of the stop tube locking claw →
1. A method for manufacturing an annular fluorescent lamp, characterized in that a NatS04 coating of SO1 product is formed on the surface layer of the sealing tube to be processed and the locking claw.