JPH03280329A - Manufacture of fluorescent lamp - Google Patents

Abstract

PURPOSE:To easily seal quick silver in a bulb by inserting a tablet provided with a quick silver getter in a pore of the bulb with a room, and by preferentially heating the tablet and the quick silver getter in turn. CONSTITUTION:A pore 14 is bored in a bulb. A tablet 17 is then inserted into the pore 14 with play, and then, the bulb is put in a vacuum atmosphere, and the air in the bulb 20 is vacuum-exhausted through a very fine gap between the tablet 17 and the pore 14. The bulb is then put in a rare gas atmosphere, and rare gas is guided into the bulb thorugh the very fine gap around the tablet 17. The tablet 17 is then preferentialy heated and melted, and after the pore 14 is airtightly closed, a quick silver getter 18 is preferentially heated and is ejected into the quick silver bulb 20. The quick silver can thus be sealed in the bulb very easily, and manufacturing workability of a fluorescent lamp can be improved thereby.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Field of Application) The present invention relates to a method for manufacturing a fluorescent lamp suitable for a chipless flat fluorescent lamp omitting an exhaust pipe. This invention relates to a method of manufacturing a fluorescent lamp that improves the method of encapsulating mercury.

(Prior Art) Conventionally, this type of flat fluorescent lamp has an exhaust pipe 2 protruding from one end of a flat bulb 1 as shown in FIG. After the air is exhausted, a rare gas is sealed in the valve 1.

However, in this flat fluorescent lamp, the exhaust pipe 2 protrudes outward, so when this flat fluorescent lamp is installed as a backlight for a liquid crystal display panel, for example, the area around the exhaust pipe 2 becomes a dead space. This goes against miniaturization.

Therefore, in recent years, a chipless flat fluorescent lamp without the exhaust pipe 2 has been desired.

In this chipless flat fluorescent lamp, it is not possible to exhaust the air inside the bulb 1 and fill it with a rare gas through the exhaust pipe 2, so this evacuation and filling of the rare gas are carried out by housing the bulb 1 in a vacuum chamber (not shown). This is done by vacuum sealing.

However, even with such a vacuum sealing method, mercury particles cannot be dripped into the bulb 1.

Therefore, a method was considered in which a mercury getter that releases mercury by heating is fixed inside the bulb 1, the bulb 1 is sealed, and then the mercury getter is selectively heated using high-frequency induction heating, and the mercury is released into the bulb 1. It will be done.

The following method can be considered as a method for fixing such a mercury getter inside the bulb 1.

(1) The electrode (not shown) built into the bulb 1 itself is composed of a mercury getter.

(2) Fix the mercury getter to a part of the electrode by spot welding or the like.

(3) As shown in FIG. 10, a small chamber 5 for accommodating a mercury getter 4 is provided in the planar bulb 3.

(Problems to be Solved by the Invention) However, in such a method, in the case of (1) above, it is extremely difficult to construct the electrode itself from a mercury getter in terms of molding process. In addition, due to the heating when the lamp is lit,
When the mercury getter operates, the mercury getter adsorbs impurity gases generated during lamp manufacturing and impurity gases released from the phosphor film and other parts during lamp life, and releases them into the bulb 1 again. There is a problem that this causes instability of equal discharge.

Regarding (2) above, there is also a problem that it is difficult to spot weld the mercury getter to a part of the electrode, and the mercury getter is more likely to peel off than the electrode.

Furthermore, in case (3), the small chamber 5 is provided in the valve 3, which is contrary to miniaturization.

Furthermore, it is not preferable to fix the mercury getter within the effective light emitting part of the bulb 1 because the mercury getter will form a shadow and cause uneven brightness.

The present invention has been made in consideration of the above circumstances, and its object is to provide a method for manufacturing a fluorescent lamp that allows mercury to be easily sealed in a chipless bulb.

[Structure of the invention]

(Means for Solving the Problems) In order to solve the above problems, the present invention is configured as follows.

That is, in the present invention, a vent hole is provided in a bulb having a phosphor film coated on the inner peripheral surface and a pair of electrodes built therein, and a mercury getter that releases mercury by heating is provided in the vent hole. The mercury getter is accommodated in the bulb by inserting a tablet with a melting point lower than that of the bulb with some play during or after the bulb is assembled, and then the bulb is evacuated in a vacuum atmosphere. exhaust,
After that, a rare gas is introduced into the valve in a rare gas atmosphere, and then the tablet is selectively heated and melted to airtightly close the vent hole, and then the mercury getter is selectively heated. mercury is discharged into the bulb.

(effect) First, a vent hole is drilled in the valve.

Next, the tablet is inserted into the vent hole with some play, and then the valve is placed in a vacuum atmosphere, and the air inside the valve is evacuated through the minute gap between the tablet and the vent hole.

Next, the valve is placed in a rare gas atmosphere, and the rare gas is introduced into the valve through the microgap around the tablet.

Thereafter, the tablet is selectively heated to melt and the vent is hermetically closed, and the mercury getter is then selectively heated to release the mercury into the bulb.

Therefore, according to the present invention, mercury is very easily sealed in the bulb by inserting a tablet provided with a mercury getter with play into the vent hole of the bulb and selectively and sequentially heating these tablets and the mercury getter. This makes it possible to improve the workability of manufacturing fluorescent lamps.

(Example) An example of the present invention will be described below based on FIGS. 1 to 8.

FIG. 3 is an exploded perspective view of an embodiment of the present invention, in which a spacer 2 made of a rectangular frame made of glass having the same shape and size as the outer peripheral edge of the back plate 11 is placed on the back plate 11 made of rectangular plate glass.
As shown in Fig. 6, the frit glass 1 with a low melting point
3, and a ventilation hole 14 is cut out in one short side of the spacer 12 to penetrate the inside and outside of the spacer 12.

Next, a pair of electrodes 15a and 15b, such as a hollow cathode type cold cathode, on the left and right sides in FIG. These pair of electrodes 15a
, 15b are bent with a nickel plate or the like into a U-shape, for example, and these U-shaped openings are made to face each other.

Further, the pair of electrodes 15a, 15b has a pair of band-shaped lead pieces 16a, 16b integrally provided at one end in the axial direction to protrude outward in the axial direction, and the tip portions of these lead pieces 16a, 16b As shown in FIG. 6, it extends outward from the mating surface of the back plate 11 and the spacer frame 12, and is connected to a lighting circuit (not shown).

Thereafter, the tablet 17 shown in FIG. 2 is inserted into the ventilation hole 14 with some play as shown in FIG. 4.

The tablet 17 is made by press-molding low-melting-point frit glass into a convex shape, and the width of the convex upper protrusion 17a is formed to be slightly smaller than the opening width of the vent hole 14.
a is inserted into the ventilation hole 14 with some play.

Further, a T-shaped vertical leg portion 18a of a substantially T-shaped mercury getter 18 is implanted at the tip of the protrusion 17a.

The horizontal portion 18b of the mercury getter 18 has mercury 18c attached to the outer surface of a strip-shaped thin plate made of, for example, an alloy of zirconium and aluminum. By heating the mercury getter 18, the phosphor film, the back plate 11, the spacer 12, etc. The substrate 18b absorbs impurity gas emitted from parts such as the mercury 18c, and mercury gas is emitted from the mercury 18c.

After the tablet 17 configured in this way is loosely inserted into the ventilation hole 14 from above in the figure as shown in FIG. 4, it is placed on the spacer 12 with approximately the same external shape as shown in FIG. A bulb 20 is constructed by coaxially sealing a front plate 19 made of a transparent glass plate of the same size with a frit glass 13 as shown in FIGS. 5 and 6.

However, at this time, as shown in FIG. 5, the upper and lower ends of the tablet 17 are not adhered to the front plate 19 and the back plate 11 by the frit glass 13, but are simply inserted loosely into the ventilation hole 14. .

Then, the valve 20 assembled in this way is
A high-frequency induction heater in a vacuum chamber 21 shown in the figure is fixed to a heater/fixing jig 22 made of carbon, and so-called vacuum sealing is performed.

That is, first, when the inside of the vacuum chamber 21 is evacuated,
Air within the valve 20 is exhausted to the outside of the valve 20 through a minute gap between the vent hole 14 of the valve 20 and the tablet 17 loosely inserted therein.

Next, the vacuum chamber 21 is filled with a rare gas such as argon.

Then, this rare gas such as argon is introduced into the valve 20 through the minute gap around the tablet 17.

Next, in this state, the tablet 17 is selectively heated by the infrared image furnace 23 located above it.

As a result, the front and back plates made of glass 19°11,
The entire tablet 17, which has a lower melting point than the spacer 12, is melted and welded to the spacer 12 as shown in FIG. At the same time, the mercury getter 18 is fixed within the bulb 20.

After that, the mercury getter 18 inside the bulb 20 is heated by the high frequency induction heater (not shown) of the heater/fixing jig 22.
When heated by high frequency induction, mercury 18 of mercury getter 18
Mercury is released into the bulb 20 from c.

Therefore, according to this embodiment, the vent hole 14 of the valve 20
Mercury can be sealed in the bulb 20 by a simple method of loosely inserting the tablet 17 inside and selectively heating the tablet 17 and the mercury getter 18.

Further, as shown in FIG. 1, the mercury getter 18 is fixed behind one electrode, for example 15b, and is located outside the effective light emitting surface of the bulb 20, so that it is possible to prevent the mercury getter 18 from being in the shadow. Furthermore, since a small chamber or the like for storing the mercury getter 18 is not provided protrudingly, generation of dead space can be prevented.

In addition, in the above embodiment, the spacer 1 is placed on the back plate 11.
Although the case has been described in which the tablet 17 is loosely inserted into the vent hole 14 during the assembly process of the valve 20 after the valve 20 is sealed, the present invention is not limited to this (for example, when the tablet 17 is loosely inserted into the vent hole 14). After completing the assembly of the valve 20 by sealing the front plate 19, the protrusion 17a of the tablet 17 and the mercury getter 18 may be loosely inserted into the vent hole 14 from the outside. getter 1
It is necessary that the length in the longitudinal direction of the ventilation hole 8 is shorter than the width direction of the ventilation hole 14.

[Effects of the Invention] As explained above, the present invention is capable of selectively heating and melting the tablet by inserting the mercury getter into the valve by inserting the tablet provided with the mercury getter into the vent hole of the valve. By doing this, the mercury getter can be easily fixed inside the bulb.

Therefore, the work of fixing the mercury getter inside the bulb is simplified, and the workability of fluorescent lamp manufacturing can be improved.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a flat fluorescent lamp to which the method for manufacturing a fluorescent lamp according to the present invention is applied, with the front plate thereof omitted; FIG. 2 is a perspective view of the tablet shown in FIG. 1 before melting; Fig. 3 is an exploded perspective view of the bulb of the fluorescent lamp shown in Fig. 1, Fig. 4 is a partial plan view of the tablet shown in Fig. 2 loosely inserted into the vent hole shown in Fig. 3, and Fig. 5. is a side view of the tablet inserted into the valve vent;
Fig. 6 is a front view of the valve shown in Fig. 3 after assembly is completed, Fig. 7 is a front view showing the state when the valve is vacuum sealed in a vacuum chamber, and Fig. 8 is a front view of the valve shown in Fig. 1. FIG. 9 is a perspective view of a conventional flat fluorescent lamp having an exhaust pipe, and FIG. 10 is a partly omitted plan view of another conventional flat fluorescent lamp. 14... Ventilation hole, 17... Tablet, 18...
Mercury getter, 20... valve, 21... vacuum chamber.

Claims (1)

[Claims] A vent hole is provided in a bulb that has a phosphor film coated on its inner circumferential surface and a pair of electrodes built therein, and a mercury getter that releases mercury by heating is provided in the vent hole, and the temperature is lower than that of the bulb. The mercury getter is accommodated in the bulb by inserting a melting point tablet with some play during or after assembly of the bulb, and then the interior of the bulb is evacuated in a vacuum atmosphere. In a rare gas atmosphere, a rare gas is introduced into the valve, and then the tablet is selectively heated and melted to airtightly close the vent hole, and then the mercury getter is selectively heated. A method for manufacturing a fluorescent lamp, comprising: releasing mercury into the bulb.