JPS5916697B2 - How to manufacture fluorescent lamps - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a method for manufacturing a fluorescent lamp, and more particularly, a method for accurately enclosing a small amount of mercury without impairing the characteristics of the fluorescent lamp or contaminating the working environment. It is related to.

Traditional methods of filling mercury in fluorescent lamps are generally
This is done during the exhaust process as shown in the plan view of the figure.

That is, in the exhaust system having a plurality of rotating exhaust heads (not shown) shown in FIG. 1, the valve is connected to the exhaust system via the exhaust pipe at position 2.

As the exhaust head rotates, the air in the air pump starts to be discharged, and then enters the heating furnace 3.

The valve is heated to around 400°C in this heating furnace 3,
The storage gas (H2) of the phosphor coated on the inner wall of the bulb
O, 02, CO2, etc.) are discharged and then the valve enters the electrode treatment device 4, 4'.

Here, electricity is applied to the electrode filaments at both ends of the bulb to heat and decompose the carbonate, which becomes an electron radioactive substance, to activate it.

During this time, H2O is generated from the carbonate. CO2,C0,0
For the purpose of discharging gas such as After performing a so-called mercury flush to promote gas discharge and increase the degree of vacuum, an appropriate amount of mercury particles is dropped again from the mercury dropping device at position 6.

Next, at the position of the inert gas filling device 7 placed next to the electrode processing devices 4 and 4', the valve is isolated from the exhaust system and an inert gas such as argon gas is filled in the valve. Subsequently, the exhaust pipe is melt-sealed by the disposed exhaust pipe melt-sealing device 8, and the valve is taken out from the exhaust device at position 9.

In this conventional method, mercury is dropped midway through the electrode treatment device, vaporized, and discharged outside the bulb, which is highly effective in removing impurity gas inside the bulb, but the drawback is that the amount of mercury remaining inside the bulb varies widely. There is.

The amount of mercury vaporized and discharged outside the pulp varies depending on changes such as the temperature of the valve, the surface area of the mercury particles, the evacuation time, and the resistance of the evacuation system. The amount of mercury that ultimately remains in the bulb varies over a wide range because it condenses on the inner wall of the exhaust pipe, which has a relatively low temperature, and then falls back into the bulb due to mechanical vibrations.

In order to secure the minimum necessary amount of mercury in any bulb, taking the above fluctuations into consideration, the total amount of mercury required in the evacuation process must be 4 to 6 times the amount of mercury required to be sealed.

Therefore, depending on the lamp, the amount of mercury that needs to be filled may be about 3 to 4 times the amount that needs to be filled, which has the drawback of causing deterioration of the lamp characteristics due to the mercury.

In addition, from the perspective of contaminating the work environment due to mercury, there is a huge amount of work needed to recover the mercury discharged outside the valve during the mercury flush from the exhaust system, and a trap device to prevent mercury vapor from diffusing into the atmosphere from the exhaust system. It has the drawbacks of high cost and the need for careful attention.

Recently, as a method to solve these drawbacks, a mercury emitting element such as a mercury alloy or a mercury compound and a non-evaporable getter agent are installed near the electrodes in the bulb, and mercury is not dropped during the evacuation process, but after the evacuation process is completed. A method has begun to be put into practice in which the mercury emitting element and the non-evaporable getter agent are heated to release mercury into the tube and impurity gas released during heating is removed using the getter agent.

This method not only allows the lamp to be filled with the minimum amount of mercury required, but also eliminates the need to handle mercury during the exhaust process, which provides a major advantage over conventional methods in preventing mercury contamination in the working environment.

However, this method also has drawbacks compared to conventional methods.

In this method, mercury is not dropped during the electrode treatment with exhaust, so the mercury flooding effect that promotes the discharge of impure gas cannot be obtained, resulting in a melt-sealed valve that still contains a considerable amount of impure gas.

This impure gas is largely adsorbed by the phosphor on the tube wall by the time the mercury emitting element and getter are heated, and even if the getter is activated, its ability to remove impurity gas is limited by the time the mercury emitting element is heated. Impure gases (H2O, CO2
, C09H2, etc.), a getter installed in a normal electrode part is at full capacity and cannot remove all impurity gases.

Therefore, when a lamp is lit with this impure gas, there are drawbacks such as blackening of the end of the tube and deterioration of the luminous flux, which impairs the lighting characteristics.

In order to completely remove these impurity gases before lighting, it is possible to increase the surface area of the getter, but this would require installing the getter over a fairly large area other than the vicinity of the electrode. Complicating the manufacturing process,
This will reduce the yield.

In addition, the chemical activity of the getter changes depending on the processing conditions of the getter, making it impossible to control it sufficiently.There are also problems such as the getter's activity being too high, which can lead to early blackening of the end of the tube while the lamp is being lit. .

This invention was made in order to improve the above-mentioned drawbacks.A mercury-emitting element made of a mercury alloy or a mercury compound is provided near the electrode of a fluorescent lamp, and the mercury-emitting element is heated after the evacuation process is completed to release mercury. In this method, the heating activation treatment of the electrode material during the exhaust process is divided into two parts: the first half of the bulb heating process and the second half of the bulb heating process. By a simple and inexpensive method,
The present invention provides a method that eliminates the drawbacks of the method using a mercury emitting element and a getter agent, removes impurity gas within the lamp, and prevents blackening of the end of the lamp tube and deterioration of the luminous flux.

Next, the details of this invention will be explained using the drawings.

A mercury-emitting element, such as Ti (titanium)-Zr, is placed near the electrode.
A fluorescent lamp bulb equipped with a (zirconium)-Hg (mercury) compound and a non-evaporable getter, such as a Zr (zirconium)-At (aluminum) alloy, is used with the exhaust system shown in FIG. 2, which is an embodiment of the present invention. A case in which a fluorescent lamp is manufactured using this method will be explained.

In Figure 2, the numbers in the figure that are the same as those in Figure 1 used to explain the mercury dropping method are the same as the conventional exhaust equipment, and b, io, and 1o' are the heating furnaces. This is the electrode processing equipment installed in the first half of Section 3.

In FIG. 2, in position 2 of the exhaust system 1 having a plurality of exhaust heads (not shown) rotating in a counterclockwise direction, the valve is connected to the exhaust system through an exhaust pipe provided at one end. Connected.

As the exhaust head rotates, the air inside the valve starts to be discharged, and then the valve enters the heating furnace 3 and starts forced heating from the outside. The electrode processing device 10.10' starts energizing the electrode filaments at both ends of the bulb, and thermal decomposition of the electrode material begins.

However, according to experiments, it is important to start the thermal decomposition of the electrode material after the pressure inside the bulb is reduced to 6.0 Torr or less in order to prevent oxidation of the electrode filament.

Experiments have shown that when the temperature exceeds 6.0 Torr, oxidation of the electrodes occurs, causing blackening of the lamp and impairing its life characteristics.

As the temperature of the bulb increases, gases such as water, CO2, etc. stored in the phosphor applied to the inner wall of the bulb are released into the bulb, and the electrode material such as carbonate is heated. As the decomposition occurs, gases such as CO2, 02, and CO are released into the valve, and these gases are simultaneously exhausted to the outside of the valve by the exhaust system through the exhaust pipe.

At this time, since the phosphor is in a high temperature state, impurity gas from the electrode material is not adsorbed by the phosphor.

Electrode processing by the first electrode processing apparatuses 10 and 10' is completed before the bulb temperature reaches 300°C.

During this process, most of the carbonate is decomposed, most of the gas release from the electrode is completed, and the carbonate is converted into an oxide.

Continuing the first electrode treatment step to a temperature of 300'C or higher will cause oxidation of the electrode filament and lead material due to oxidizing impurity gas in the bulb, such as occluded impurity gas released from the bulb, and should be avoided.

Heating of the bulb continues further, and the temperature near the outlet of the heating furnace 3 reaches 400-450°C.

Next, a second electrode processing device 4, 4 connected to the heating furnace 3
When the valve is turned on, the electrode filament is energized again and the electrode material is processed.

This treatment is performed by heating the electrode material, which has almost changed to an oxide, in the first electrode treatment apparatus 10, 10' to activate it, and at the same time, the electrode material is heated during the inert gas filling process described later. This is done to prevent contamination with impure gases.

Therefore, less gas is released. In other words, in the method using a mercury emitting element and a getter agent, there is no step to release impure gas from the electrode material by mercury flushing, etc., and as a result, a considerable amount of impure gas is adsorbed by the phosphor. , this kind of thing could have been prevented.

Next, the valve is cut off from the exhaust system at the position of the inert gas filling device 7 arranged in series with the second electrode processing device 4, 4', and an inert gas such as argon gas at a pressure of several Torr is supplied. is included.

Next, the exhaust pipe of the valve is melt-sealed by the exhaust pipe melt-sealing device 8 disposed following the inert gas filling device T, and then the valve is taken out from the exhaust device 1 at position 9, and the next mercury In the heating process of the emitting element and the non-evaporable getter, for example, the mercury is sent to a high frequency induction heating device, and mercury is released by heating the mercury emitting element, and in order to adsorb impurity gas released into the lamp at the time of this mercury release. At the same time, the non-evaporable getter material is heat-activated and sent to the next process, and then the base frame undergoes the usual fluorescent lamp manufacturing processes such as process, aging process, and basing process to become a finished lamp.

The present invention is normally manufactured through this series of manufacturing steps, but if necessary, it is possible to simply fill in an inert gas during a certain step of the second electrode processing device or a step up to the exhaust pipe melt sealing device 8 that is connected thereto. The evacuation operation (equipment not shown) may be repeated.

Next, the effects of the present invention will be explained with reference to examples.

Example 1 An example of use in a 40 watt rabbit start type lamp will be explained.

Z as a non-volatile getter is placed in the center of a 0.12 mm thick, 6.0 mm wide iron plate over a width of 31 mm.
r −A as an alloy and T i as a mercury-releasing element.
-Hf alloy is crimped on the front and back sides to form an electrode part surrounding the electrode, and this is sealed to the bulb.

This sealed valve is heated in an exhaust furnace in the conventional manner, and the electrode is decomposed and activated after the heating furnace, and argon gas is sealed in and exhausted during that process, which is the so-called argon flush method (specification B). A method in which argon flushing is not performed (Specification A), and a method in which argon flush is performed and the subsequent exhaust capacity is increased (increasing the exhaust speed by 20 factors) (Specification C).
The exhaust process is completed by four methods: 1) and a method of activating the decomposition of the electrode in the first and second half of the exhaust heating furnace of this invention (specification D), and then the mercury releasing element and getter are heated to 950°C and 30°C using a high-frequency heating device. The lamp was heated for seconds to release mercury into the tube and activate the getter, and then a lamp was manufactured in the usual manner and its characteristics were measured. Table 1 shows the results.

In addition, mercury is added using a dropping machine (Rotsher) during electrode treatment.
Comparative measurements were also carried out on lamps manufactured by the conventional general method (specification E) of dripping and flashing mercury.

Note that argon was used as the filler gas in all cases.

In Table 1, the degree of blackening at the end of the tube is grade 0 at the initial stage of lighting;
The degree of occurrence of blackening at the end of life is set as 5.0 grade, and the degree of occurrence of blackening is divided into series.

Specification A has a large amount of residual impurity gas, so the discharge starting voltage
The initial luminous flux, luminous flux maintenance rate, and incidence of blackening are poor, and argon
Flushed products (Specification B has improved in all properties, but in order to achieve the characteristics of the conventional method using mercury dripping (Specification E), it is necessary to modify the equipment such as improving the evacuation property. (Specification C).

On the other hand, in the method (specification D) in which electrode decomposition is activated in the first and second halves of the exhaust heating furnace of the present invention, most of the electrode decomposition gas is released in the first half thermal decomposition process, and this gas is Most of the gas is evacuated during the heating process, and there is little gas released during electrode activation in the latter half, so there is almost no residual impurity gas at the filling position, so it was possible to obtain good characteristics despite being a simple method.

Example 2 A 110 Watt Rabbit Start type lamp was manufactured in the same manner as in Example 1.

In addition to Specifications C, D, and E in Example 1, the specifications are F, which is a method for activating electrode decomposition in the first half and second half of the exhaust heating furnace. The lamp was also manufactured using an argon flush method in the process.

The characteristic results are shown in Table 2.

In Table 2, the specifications are currently commonly used specifications C and E.
Although the performance was better, specification F had even less residual impurity gas, so it was possible to improve the characteristics even more than the specification.

In addition, in the above embodiment, T is used as the mercury supply element.
Although the i-Zr-Hg compound is used, other mercury compounds or mercury alloys may also be used. Furthermore, mercury particles may be placed in a container and sealed inside the lamp tube. In this case, the container may be exposed to high frequency All you have to do is heat it, cut it, and release the mercury into the tube.

As described above, in order to fill a fluorescent lamp with the minimum amount of mercury necessary for small variations and to prevent mercury vapor from being emitted at all during the lamp manufacturing process, the present invention installs a predetermined amount of mercury emitting elements in the lamp. In the method of manufacturing a fluorescent lamp by heating this after exhaust gas sealing and releasing mercury,
This method was used to improve the characteristics such as discharge starting voltage, luminous flux, and degree of blackening due to the increase in residual impurity gas during exhaust compared to the conventional mercury dropping method. The electrode decomposition activation process is carried out in two parts, the first half and the second half.It is an extremely simple method with great effects, as it does not require any special improvements to the exhaust system, etc. (the conventional mercury dripping method equipment can be used as is). This is something that can be obtained.

In addition, this invention can eliminate the drawbacks of the method using a mercury emitting element and getter, in that impurity gas generated in the blind electrode treatment process is adsorbed by the phosphor, and it is possible to stabilize the amount of encapsulated mercury. , it provides many effects such as improved characteristics and simplification of manufacturing equipment.

[Brief explanation of the drawing]

FIG. 1 is a plan view for explaining a conventional exhaust device, and FIG. 2 is a plan view for explaining the method of the present invention, showing an exhaust device and a high-frequency induction heating device connected thereto. In addition, the same reference numerals in the figures indicate the same or equivalent parts, and 1
is the exhaust system, 2 is the valve mounting position, 3 is the heating furnace, 4, 4
' is a second electrode processing device, 6 is a mercury dropping position, I is an inert gas filling device, 8 is an exhaust pipe melt sealing device, and 9 is a valve extraction position.

Claims (1)

[Claims] 1. Comprising a phosphor coated on the inner surface, an electrode provided at the inner end, a mercury emitting element and a non-evaporable getter installed near the electrode, and an exhaust pipe. An evacuation step in which gas is vented from the inside of a bulb equipped with a fluorescent lamp bulb via the exhaust pipe, and heating of the electron radioactive material deposited on the electrode is divided into a front stage and a rear stage of this exhaust step. an electrode treatment step for performing a decomposition activation treatment; a step for filling inert gas at a predetermined pressure into the valve after the exhaust step; a step for melt-sealing the exhaust pipe after filling the inert gas in the valve; A method for manufacturing a fluorescent lamp, comprising the steps of supplying mercury from the mercury emitting element into the bulb after the tube is melt-sealed, and activating the getter. 2. Manufacture of a fluorescent lamp according to claim 1, characterized in that an inert gas is sealed in the bulb at a predetermined time of the electrode treatment step in the latter stage of the exhaust step to promote exhaustion of the bulb. Method. 3 The start of the electrode treatment process in the first stage of the exhaust process is as follows:
3. The method of manufacturing a fluorescent lamp according to claim 1, wherein the method is performed when the pressure inside the bulb is 6 Torr or less. 4 At the end of the electrode treatment process in the first stage of the exhaust process,
A method for manufacturing a fluorescent lamp according to any one of claims 1 to 3, characterized in that the temperature of the bulb does not exceed 300°C.