JPH0687403B2 - Method for manufacturing low-pressure mercury vapor discharge lamp - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to the manufacture of a low-pressure mercury vapor discharge lamp in which an amalgam for controlling the mercury vapor pressure during lighting is housed in a thin tube protruding from the end of a bulb. Regarding the method.

[Conventional technology]

In low-pressure mercury vapor discharge lamps typified by fluorescent lamps, in order to prevent a decrease in luminous efficiency at high temperatures,
A means for accommodating an amalgam in the valve and controlling the mercury vapor pressure in the tube within an appropriate range by the amalgam is adopted.

Amalgam is conventionally housed in a thin tube protruding from the end of the valve because it is easy to install and the temperature is relatively low.

By the way, when manufacturing a valve accommodating such an amalgam, conventionally, the other end of the valve is sealed, and the inside of the valve is exhausted through a thin tube protruding from one end of this valve. The method of accommodating the amalgam in the used thin tube was adopted.

In this case, a small tube for accommodating the amalgam and used for exhausting is formed in advance with a small diameter part for holding the amalgam, and the small diameter part holds the amalgam contained in the thin tube so as not to fall inside the valve. is doing.

[Problems to be solved by the invention]

However, according to the above method, in the thin tube sealed after exhausting and containing the amalgam, since the pressure of the inert gas sealed inside the valve is lower than the atmospheric pressure, the sealing end portion is directed inward. It has a concave shape, and its thickness is thin. As a result, during manufacturing or transportation, the amalgam housed in the thin tube moves and hits the thin sealing end portion,
It may cause cracks or cracks in the thin tubes.

In addition, since the thin tube has a small diameter portion for holding the amalgam, it becomes a resistance to gas flow when exhausting the inside of the valve, and there is also a problem that exhaust efficiency is not good.

Furthermore, when viewed from the exhaust device, an amalgam charging head must be attached to the exhaust system, which complicates the structure of the exhaust system, and also has the drawbacks that maintenance is troublesome.

Therefore, the present invention is intended to provide a method of manufacturing a low-pressure mercury vapor discharge lamp which can reduce the occurrence of cracks and cracks in thin tubes and can improve the exhaust efficiency.

[Means for solving problems]

According to the present invention, an amalgam is housed in a thin tube protruding from one end of a valve, the thin tube is sealed, and then the inside of the valve is exhausted through another thin tube protruding from the other end of the valve. is there.

[Action]

According to the method of the present invention described above, since the amalgam is housed in the thin tube on one end side that is sealed under atmospheric pressure, the thin tube does not have a thin wall thickness, and therefore even if the amalgam moves inside. The thin tube is less likely to break or crack. Further, since the valve is exhausted through a thin tube on the other end side different from the thin tube containing the amalgam, not only a large exhaust passage is secured but also evaporation from the amalgam already stored in the thin tube on the one end side. The generated mercury vapor pushes out the residual air in the bulb, so-called mercury vapor pumping action occurs, and the exhaust efficiency is improved.

Example of Invention

An embodiment of the present invention will be described below with reference to the drawings.

In the fluorescent lamp shown in FIG. 1, the arc tube bulb 1 has a substantially saddle shape. That is, the arc tube bulb 1 is formed by bending a straight tube bulb into a U-shape at its substantially middle portion, and further bending each of the middle portions into a U-shaped shape. Therefore, this type of fluorescent lamp is called a saddle type fluorescent lamp.

On the inner surface of the bulb 1, a phosphor coating 2 is formed as shown in the enlarged sectional view of FIG. Mounts 3 are sealed at both ends of the bulb 1.

As shown in FIG. 4, only one side of the mount 3 is formed by sealing the lead wires 5 and 5 to the stem tube 4 and laying the filament 6 between these lead wires 5 and 5. The part is sealed to the open end of the valve 1.

A thin tube 7 is projected from the stem tube 4, and the inside of the thin tube 7 is connected to the inside of the valve 1 through a communication hole 8 formed in the stem tube 4.

Such a mount 3 is also provided at the other end of the valve 1, and therefore a thin tube is also provided so as to project at the other end of the valve 1. The thin tube is numbered 9 to distinguish it from the thin tube 7.

An amalgam 10 is housed in the one thin tube 7.
In order to hold this amalgam 10, the thin tube 7 is formed with a small diameter portion 11 at the base thereof.

A method of supplying the amalgam 10 and a method of exhausting the amalgam 10 to the fluorescent lamp having such a configuration will be described with reference to the drawings starting from FIG.

The bulb 1 shown in FIG. 2 is formed by forming a phosphor coating 2 on the inside and mounting mounts 3 and 3 on both ends, respectively. The thin tube 7 protruding at one end has a small diameter. The part 11 is formed.

For such a valve 1, an amalgam 10 is introduced into the one thin tube 7 through the opening. As shown in FIG. 3, the amalgam 10 is hooked on the small diameter portion 11 and held in the thin tube 7.

In this state, an inert gas supply pipe 20 is connected to the thin tube 7 as shown in FIG. Then, while feeding an inert gas such as nitrogen gas into the thin tube 7 from the inert gas supply pipe 20, the burner 21 seals and cuts the upper portion of the thin pipe 7 above the portion where the amalgam 10 is housed.

In this case, heat is shielded by the shield plate 22 so that the root side of the thin tube 7 with respect to the burner 21 is not heated, and the root side of the shield plate 22 is cooled with cooling air injected from the nozzle 23.

By doing so, the amalgam 10 contained in the thin tube 7 is not heated by the flame of the sealing burner 21, and the thin tube 7
Since the inert gas is flown therein, the amalgam 10 is not oxidized and mercury in the amalgam is not wastefully released.

In this way, the valve 1 whose sealing of one thin tube 7 is completed
The inside and outside are communicated with each other through the other thin tube 9, and as shown in FIG. 5, the amalgam 10 is accommodated in the thin tube 7 which is a blind path to the other thin tube 9.

As shown in FIG. 6, an exhaust pipe 30 of an exhaust system is connected to the other thin tube 9 of the valve 1 as described above, and the inside of the valve 1 is exhausted through the exhaust pipe 30.

At the time of this exhaust, since the thin tube 9 has no small diameter portion or the like, it has a sufficient thickness, and the gas in the valve 1 smoothly flows out. Moreover, one thin tube 7 which is the above-mentioned dead end
Since the amalgam 10 stored in 1 can vaporize mercury even at room temperature, mercury vapor exists on the side of the thin tube 7, and this mercury vapor is drawn to the side of the other thin tube 9. While the mercury vapor is flowing through the bulb 1, the air or suspended matter inside the bulb 1 is pushed, and so-called mercury vapor serves as a pumping action. Therefore, the inside of the valve 1 is evacuated in a short time, moreover, the residue is less left and the evacuation capacity is improved.

When the predetermined exhaustion is completed in this way, the inert gas for starting is inserted into the valve 1 through the exhaust pipe 30, and when the amount of mercury is insufficient with the amalgam 10 alone, the predetermined amount is put into the valve 1 through the exhaust pipe 30. Of mercury.

After this, the thin tube 9 is sealed and cut by the sealing burner 31.

In this way, the fluorescent lamp shown in FIGS. 7 and 1 can be obtained.

According to the above method, the thin tube 7 containing the amalgam 10
However, since it is sealed in the atmosphere, the thin tube 7 is not formed with a thin portion or a recessed portion, and therefore even if the amalgam 10 moves in the thin tube 7, the thin tube 7 may break or crack. There is no.

Moreover, since the inside of the valve 1 is exhausted through the other thin tube 9, the exhaust capability is improved.

The experimental results comparing the method according to the present invention with the conventional method of exhausting from a narrow tube containing amalgam will be described.

The table below shows the incidence of thin tube cracking.

In addition, the following table shows the exhaust performance by the pumping action of mercury, and the exhaust performance was examined by the relative starting voltage.

The results of these experiments also show that the method of the present invention is excellent.

Although the saddle type fluorescent lamp has been described in the above embodiment, the present invention is not limited to this, and the present invention can be applied to a straight tube type, a U-shaped type and other multi-flex type fluorescent lamps.

〔The invention's effect〕

As described above, according to the present invention, the amalgam is housed in the thin tube protruding from one end of the valve, the thin tube is sealed, and the inside of the valve is exhausted through the other thin tube protruding from the other end of the valve. Therefore, since the amalgam is housed in the thin tube on one end side that is sealed under atmospheric pressure, the thin tube does not have a thin wall, and therefore the thin tube does not move even if the amalgam moves inside. It is less likely to break or crack. Further, since the valve is exhausted through a thin tube on the other end side different from the thin tube containing the amalgam, not only a large exhaust passage is secured, but also the amalgam already stored in the thin tube on the one end side is evaporated. Further, the mercury vapor pushes out the residual air in the bulb, and the so-called mercury vapor pumping action is added, so that the exhaust efficiency is improved.

[Brief description of drawings]

The drawings show one embodiment of the present invention. FIG. 1 is a perspective view of a saddle type fluorescent lamp, and FIGS. 2 to 7 are explanatory views showing the manufacturing steps in order. 1 ... Bulb, 2 ... Fluorescent film, 3 ... Mount, 6 ... Filament, 7 ... One thin tube, 9 ... Other thin tube, 10 ... Amalgam, 11 ... Small diameter part.

Claims (2)

[Claims] 1. A method of manufacturing a low-pressure mercury vapor discharge lamp in which an amalgam for controlling the mercury vapor pressure during lighting is housed in a thin tube projecting at the end of a bulb, and in a thin tube projecting at one end of the bulb. A method of manufacturing a low-pressure mercury vapor discharge lamp, comprising the steps of accommodating an amalgam, sealing the thin tube, and then exhausting the inside of the bulb through another thin tube protruding from the other end of the bulb. 2. The method for manufacturing a low-pressure mercury vapor discharge lamp according to claim 1, wherein the thin tube containing the amalgam is sealed while flowing an inert gas into the thin tube.