JPH06162997A - Closure plate sealed tube and method of manufacturing the same - Google Patents

Abstract

(57) [Abstract] [Purpose] A bead-shaped stem is used for sealing in fluorescent lamps that use conventional tubular bulbs.
Since it is impossible to reduce the size of the sealing portion even when reducing the size of the entire fluorescent lamp, there is a problem that the sealing portion becomes relatively large and dead spaces are formed at both ends. A closing plate mounting body 1 formed by mounting a lead wire 4 and an electrode 3 on a closing plate 2 made of a metal plate member is embedded in a sealing portion of a glass tube 11 via a glass wax 5. The use of the closing plate-sealed tube 10 enables the miniaturization and the improvement of production efficiency to solve the problem.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass sealed bulb formed by embedding a stem in a sealed portion of a tubular glass bulb such as a cold cathode fluorescent lamp and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, when manufacturing a tubular light bulb having an outer diameter of 6 mm or less, a fluorescent lamp 90, or the like, first, as shown in FIG. 6, a bead-shaped stem 92 is placed at a predetermined position in a glass tube 91 also serving as an exhaust tube. It is arranged to heat the glass tube 91 from outside with a burner 80 or the like while exhausting the inside of the glass tube 91, and weld the glass tube 91 and the bead portion 92a of the bead-shaped stem 92 to form the sealing portion 93, After this, as shown in FIG. 7, scribing is performed on the outside of the sealing portion 93 with a cutter 81, and the exhaust tube portion 91a of the glass tube 91 shown in FIG. 8 is chipped off to obtain the fluorescent lamp 90.

The above-described manufacturing method for the relatively small fluorescent lamp 90 and the like can prevent the electrodes 92b and the lead wires 92c from being oxidized during the sealing step, and further, the exhaust step, the sealing step, and the Since the exhaust pipe part can be chipped off almost at the same time, it is widely adopted because of its excellent mass productivity.

[0004]

However, in the above-mentioned conventional manufacturing method, since the bead-shaped stem 92 is used, the sealing portion becomes long and a non-light-emitting dead space is provided at both ends. There was a problem that occurred.

The bead portion 92a of the bead-shaped stem 92 must have a melting point equal to or higher than that of the glass tube 91 in order to prevent the deformation in the sealing step. Therefore, the encapsulation process requires heating for a long time, which causes a problem that production efficiency is reduced.

Further, in order to improve the production efficiency of the above-mentioned sealing step, when the narrow portion 91b is previously provided in the glass tube 91, the pressure in the step of performing the replacement cleaning and the exhaust in the glass tube 91. Due to the difference, the bead portion 92a
Or the bead portion 92a comes into contact with the narrow portion 91b to hinder the inflow of the purge gas for replacement, resulting in a dimensional defect or a decrease in productivity. However, the effect was not obtained as expected, and the solution of these points was a problem.

Further, since the bead-shaped stem 92 has a structure in which the lead wire 92c linearly penetrates the bead portion 92a, for example, heating in the sealing step or lead in the assembly step after the fluorescent lamp 90 is completed. Line 92
A crack caused by a tensile stress applied to c is easily communicated with the inside and outside of the fluorescent lamp 90, which causes a leak and also reduces the reliability of the fluorescent lamp 90.

[0008]

As a concrete means for solving the above-mentioned conventional problems, the present invention provides a sealing member for a glass tube, a closing plate made of a metal or ceramic plate member, a lead wire and By providing a closure plate-sealed tube and a method for manufacturing the same in which a closure plate mounting body formed by mounting electrodes is embedded via glass wax, the shortening of the sealing part is achieved. It is possible to solve the problem by improving the production efficiency as well as making it possible.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail based on an embodiment shown in the drawings. It should be noted that this embodiment will be described with reference to an example implemented in a cold cathode fluorescent lamp. Reference numeral 1 in FIG. 1 denotes a closing plate mounting body. This closing plate mounting body 1 has electrodes 3 mounted on one surface of a thin plate-shaped closing plate 2 and leads on the other surface. The wire 4 is mounted and formed.

Here, the closing plate 2 is a rectangular plate member having a side of 2.5 mm and a thickness of 0.2 mm, which is formed of, for example, a metal member of iron, a nickel alloy, or a ceramic, and has a surface thereof. Glass wax (eg Toshiba solder glass # 5
04) and the like, a glass wax film 5 is applied thereto. In the present invention, for example, a closed-plate sealed tube such as a cold cathode fluorescent lamp 10 is provided with this closed-plate mounting body 1 as shown in FIG. It is configured to be formed by sealing both ends by using.

FIGS. 3 to 5 show a method of manufacturing a closed-plate sealed tube using the closed-plate mounting body 1 in the cold cathode fluorescent lamp 10.
The manufacturing method is shown in the order of steps. First, for example, a part of a glass tube 11 having an outer diameter of 4 mm is squeezed to provide a narrow portion 11a, and the narrow plate portion 11a is provided with the closing plate mounting body. 1 is disposed so as to abut on the apex of a square, and is attached to the exhaust head 20 to perform exhaust gas and displacement cleaning with a purge gas such as N ₂ or Ar, and then fill with a predetermined enclosed gas or the like.

At this time, since the narrow portion 11a and the closing plate mounting body 1 are in contact with each other, they are mechanically held, and therefore, due to the pressure difference generated during the replacement cleaning and filling of the enclosed gas, the closing plate mounting body is No movement of position occurs at 1. Further, even in the state where the contact is made, a gap is secured with the narrow portion 11a due to the shape of the closing plate mounting body 1, and the circulation of the enclosed gas or the like is not hindered.

Next, when the vicinity of the narrow portion 11a is heated by the burner 21 while keeping the inside of the glass tube 11 at the atmospheric pressure or less, the glass wax film 5 of the closing plate mounting body 1, that is, the glass wax, is melted and the narrow portion 11a is melted. Is deformed to wrap the closing plate 2, and the closing plate mounting body 1 and the glass tube 11 are covered with the glass wax.
And are in close contact with each other in an airtight state (see FIG. 4), whereby sealing is performed.

Subsequently, the glass tube 1 which is no longer needed is scribed at a predetermined position by the cutter 22 (see FIG. 4).
If the exhaust pipe portion 11b of No. 1 is chipped off (see FIG. 5), the cold cathode fluorescent lamp 10 shown in FIG. 2 is completed. In addition, the fluorescent substance 1 is previously formed on the inner surface of the glass tube 11.
2 is to be applied.

Here, the cold cathode fluorescent lamp 1 having the above structure.
0 and the operation and effect of the manufacturing method thereof will be described. First, since the sealing plate mounting body 1 is used for sealing, the length required for this sealing is the conventional bead type stem. It is possible to make the length shorter than that of By the way, in the result of the trial manufacture by the inventor for making the present invention, the non-light emitting portion generated at both ends of the cold cathode fluorescent lamp of the conventional bead type stem is 9 mm,
With the configuration of the present invention, the length can be reduced to 7 mm, and the effect on the cold cathode fluorescent lamp 10 of this type, which is originally the most important issue for downsizing, becomes remarkable.

With the above construction, the narrow plate portion 11a and the closing plate mounting body 1 are dimensionally overlapped with each other by, for example, making the side of the closing plate mounting body 1 into a square shape. It becomes possible to provide a gap without a gap, whereby the closing plate mounting body 1 does not close the narrow portion 11a,
Therefore, at the time of replacement cleaning with the purge gas, it is possible to both inject and discharge the purge gas with a sufficient introduction pressure to improve the production efficiency, and at the same time, to move the position due to the gas pressure between the narrow portion 11a and the closing plate mounting body 1. Not to improve product accuracy.

Further, since the closing plate mounting body 1 covers the closing plate 2 formed of a metal member with the glass wax film 5 made of glass wax, the inside of the glass tube 11 is kept under atmospheric pressure during the sealing step. Sealing can be performed by heating the vicinity of the narrow portion 11a with the burner 21 to the extent that the closing plate mounting body 1 is kept in contact with the burner 21. Compared with the conventional heating that needs to melt the bead stem, The heating amount becomes small, which improves the production efficiency and reduces the generation of impure gas due to heating, which is effective for extending the life of the cold cathode fluorescent lamp 10.

In addition, since the closing plate mounting body 1 is adopted, the lead wire 4 and the electrode 3, that is, the inside and outside of the cold cathode fluorescent lamp 10 are shaped so as to be separated by the closing plate 2, for example, the lead wire 4. Even if a crack is generated on the side due to thermal stress or external stress, it does not stay at the portion of the closing plate 2 and does not communicate with the inside of the cold cathode fluorescent lamp 10, and prevents the occurrence of leak. Further, the blocking plate 2 increases the joint area with the glass tube 11 and also increases the mechanical strength against the tensile force applied to the lead wire 4, thereby facilitating the handling during the assembly process, for example.

At the same time, since the closing plate 2 is formed of a metal member, the closing plate mounting body 1 will not be deformed even when the above-mentioned heating for sealing is performed. It is possible to prevent the situation where the bead-shaped stem melts at the time of heating for sealing and is deformed to reduce the dimensional accuracy, and it is also effective for improving the dimensional accuracy of the cold cathode fluorescent lamp 10. The present invention can be applied to a light bulb if the closing plate 2 is made of ceramic.

[0020]

As described above, according to the present invention, the closing plate mounting body formed by mounting the lead wire and the electrode on the closing plate made of a metal plate member or ceramic in the sealing portion of the glass tube. By adopting a closed-plate sealing type bulb in which is embedded via glass wax and its manufacturing method, firstly, the length required for sealing is compared with that of the conventional bead type stem. It is extremely effective for miniaturization of cold cathode fluorescent lamps of this type, etc., where miniaturization is the most important issue.

Secondly, with the above configuration,
A space can be freely provided between the narrow portion of the glass tube and the closing plate mounting body to speed up the replacement cleaning, reduce the heating amount for the glass tube during the sealing step to improve the production efficiency, and It also reduces the generation of impure gas and is effective for extending the life. In addition, it also improves the heat resistance and the dimensional accuracy by configuring the closing plate mounting body with a metal or ceramic plate-shaped member. Will be effective.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a closing plate mounting body which is a main part of a closing plate sealed tube of the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of a closed-plate sealed tube of the present invention.

FIG. 3 is a cross-sectional view showing a sealing step of the method for manufacturing a closed-plate sealed tube according to the present invention.

FIG. 4 is a sectional view showing a scribing step of the method for manufacturing a closed-plate sealed tube according to the present invention.

FIG. 5 is a cross-sectional view showing a tip-off step of the method for manufacturing a closed-plate sealed tube according to the present invention.

FIG. 6 is a cross-sectional view showing a sealing step of a conventional method for manufacturing a tube.

FIG. 7 is a sectional view showing a scribing process in the same manner.

FIG. 8 is a cross-sectional view showing a chip-off process of the same.

[Explanation of symbols]

 1 ... Closure plate mounting body 2 ... Closure plate 3 ... Electrode 4 ... Lead wire 5 ... Glass wax film 10 ... Cold cathode fluorescent lamp 11 ... Glass tube 11a ... Narrow part 11b ... Exhaust pipe part 20 ... Exhaust head 21 ... Burner 22 ... Cutter

Claims (2)

[Claims] 1. A sealing plate mounting body formed by mounting a lead wire and an electrode on a blocking plate made of a metal or ceramic plate-like member is embedded in a sealing portion of a glass tube via glass wax. A closure plate-sealed tube characterized by the above. 2. A step of disposing a closing plate mounting body, in which glass wax is adhered, on a narrowing portion provided in a part of a glass tube at an apex thereof, and in the glass tube, the narrowing portion and the closing plate mounting body. A step of exhausting gas from the gap by gas displacement cleaning, and a step of heating the narrow portion from the outside of the glass tube while maintaining the glass tube inside at an atmospheric pressure or lower, and sealing the narrow portion and the closing plate mounting body. And a step of cutting off the exhaust pipe portion of the glass tube from the sealed portion.