JPH0447894Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Purpose of the Invention] (Field of Industrial Application) The present invention relates to a bent fluorescent lamp in which the mercury vapor pressure within the tube is controlled by an amalgam.

(Prior Art) In general, when a fluorescent lamp has a curved discharge path, a long discharge length can be achieved in a small space, and this has the advantage of being able to be made smaller and more compact.

However, when high input is applied to this type of bent fluorescent lamp or when the bulb diameter is narrowed, the tube wall load increases, heat dissipation becomes insufficient, and the bulb temperature rises. Therefore, when pure mercury is used as the mercury vapor source, the mercury vapor pressure inside the bulb exceeds the optimum value, causing problems such as a decrease in luminous flux.

On the other hand, when a fluorescent lamp is operated under the above-mentioned severe temperature conditions, it is known that using amalgam instead of pure mercury makes it easier to control the mercury vapor pressure within an appropriate range. It is being

However, the method of controlling mercury vapor pressure using amalgam utilizes the property that the vapor pressure of amalgam is lower than that of pure mercury at the same temperature. If the temperature of the amalgam itself is low,
The temperature at which the lamp exhibits the optimum mercury vapor pressure cannot be reached, and the temperature at which mercury is released becomes slow. As a result, there is a drawback that the rise characteristics of the luminous flux are poor and it takes time to reach a stable state.

For this reason, as described in Japanese Patent Application No. 59-73973 filed by the present applicant, in addition to the main amalgam that controls the mercury vapor pressure during steady lighting, it has been proposed to adsorb floating mercury in the pipe when the lights are turned off. In addition, it has been proposed to use an auxiliary amalgam that releases the adsorbed mercury during the initial stage of lighting, including during startup.
In the above-mentioned prior application, the auxiliary amalgam is installed near the electrode at the end of the valve, and the main amalgam is housed in an exhaust thin tube protruding from the end of the valve.

(Problem to be solved by the invention) However, in the past, since the auxiliary amalgam was installed near the electrode at the end of the bulb, the mercury vapor released from this auxiliary amalgam diffused throughout the discharge space. There is a problem with slow speed. In other words, in this type of bent fluorescent lamp, the discharge path has a complicated meandering shape, so the diffusion of mercury vapor is suppressed in some parts due to gravity and the narrowing of the inner diameter, and in some parts, the diffusion of mercury vapor is suppressed. Since the rate of increase in tube wall temperature is slow, phenomena such as excess mercury being adsorbed on the tube wall occur, and therefore it takes time for mercury vapor to diffuse, especially to the center. For this reason, there was a drawback that the luminous flux rise time was long.

The present invention promotes the rapid diffusion of mercury vapor released from the auxiliary amalgam at the time of startup, shortens the time for the mercury vapor pressure within the bulb to reach a predetermined pressure as a whole, and shortens the luminous flux rise time. The purpose of this invention is to provide a bendable fluorescent lamp that can be used.

[Structure of the invention] (Means for solving the problem) The present invention installs an auxiliary amalgam in the middle of the discharge path between both electrodes, and heats the auxiliary amalgam for a certain period of time near the auxiliary amalgam at the time of startup. It is characterized by the installation of a heater.

(Function) According to the present invention, an auxiliary amalgam is installed in the middle of the discharge path between both electrodes, and the auxiliary amalgam is heated for a certain period of time by a heater at startup.
Mercury vapor is supplied from the auxiliary amalgam to the middle of the discharge path, and the mercury vapor is rapidly diffused throughout the bulb. Therefore, the time required for the mercury vapor pressure within the bulb to reach a predetermined pressure as a whole is shortened, and the luminous flux rise time is shortened.

(Embodiment of the invention) The present invention will be described below based on an embodiment shown in the drawings.

In the fluorescent lamp device shown in FIG. 4, 1 is a bent fluorescent lamp, 2 is a base made of synthetic resin, and 3, 3 are base pins. The base 2 is closed by a closing plate 4, and the bent fluorescent lamp 1 is attached to this closing plate 4. In addition,
Inside the cap 2, lighting circuit components such as a ballast 25, a lighting tube 26, and a capacitor 27 shown in FIG. 5 are accommodated.

The bent fluorescent lamp 1 is made up of three U-shaped bulbs 5a, 5b and 5c joined together at their ends, and will be described below with reference to FIGS. 1 to 3.

FIG. 1 shows the bent fluorescent lamp 1 unfolded, and the U-shaped bulbs 5a, 5b and 5c are
By blowing out the side wall at the end and fusing the blow-through parts to each other, they are interconnected through these welded parts 6, 6, forming a single meandering discharge path as a whole. .

Note that a phosphor coating 7 is applied to the inner surface of each U-shaped bulb 5a, 5b, and 5c.

U-shaped valves 5a and 5c located at both ends
have electrode mounts 8, 8 sealed to one end of each.

As one of these electrode mounts 8, 8 is shown in FIG. 2, lead wires 10, 10 are sealed to a stem 9 sealed at the open end of the bulb.
0 and 10 with a coil filament 11 wrapped around them. In addition, the coil filament 11
Although not shown in the figure, an emitter is applied.

An auxiliary amalgam 12 is welded to one of the lead wires 10 as in the conventional case. The auxiliary amalgam 12 is made by depositing an amalgam-forming metal such as indium on the surface of a metal foil such as stainless steel or nickel, or a high melting point metal foil made of molybdenum, tantalum, or niobium, by plating or vapor deposition.

An exhaust tube 13 is connected to the stem 9, and the exhaust tube 13 is sealed after filling the lamp with an inert gas such as argon. Note that this exhaust thin tube 13 is connected to the valve 5a.
It is also used for blowing air or inert gas into the valves 5a and 5c when blowing over the end side walls of the valves 5a and 5c to fuse the overburdens together.

An exhaust capillary 13 connected to at least one of the stems 9, 9 located at both ends of the lamp protrudes outward, and a main amalgam 14 is housed in this protrusion. This main amalgam 14 is held by a constricted portion 15 formed at the root of the exhaust thin tube 13, and is supported so as not to enter the valve. In addition, the main amalgam 14
is composed of indium, bismuth, tin, lead, and an alloy of these metals mixed appropriately with mercury, and is housed in the exhaust capillary tube 13 as a substantially spherical lump.

In addition, the central portion U that does not have the electrode mount 8
The length of both ends of the U-shaped bulb 5b is the same as that of the U-shaped bulbs 5a and 5 on both sides, which enclose the electrode mount 8.
Both ends of the U-shaped bulb 5b, which is longer than the welded portions 6, 6 and therefore have no electrode mount 8, are provided with extensions 16, 16 that are longer than the fused portions 6, 6.

One extension 16 is sealed by a stem 17 as shown in FIG.
An exhaust thin tube 18 is connected to the exhaust tube 18. Exhaust tube 1
Reference numeral 8 is used to blow air or inert gas into the valve 5b when the end side wall of the U-shaped valve 5b is blown out, and the three U-shaped valves are connected by the fused parts 6, 6. After 5a, 5b and 5c are joined, they are sealed and cut.

The stem 17 has a pair of lead wires 19, 19.
are sealed, and a coil heater 20 is wrapped around these lead wires 19, 19. In addition,
The coil heater 20 may have a similar structure to the coil filament 11 provided at both ends of the lamp, but the emitter is not applied to the coil heater 20.

Another auxiliary amalgam 21 is welded to one lead wire 19 close to the coil heater 20. This auxiliary amalgam 21 may be similar to the auxiliary amalgam 12 described above.

In this embodiment, the auxiliary amalgam 21 is located inside the U-shaped bulb 5b than the coil heater 20, and is located in the vicinity of the fused portion 6 in the U-shaped bulb 5b, and interacts with the arc (positive column) area during lighting. It is placed in a certain position.

In the bent fluorescent lamp 1 having such a structure, when the lamp is started, the coil heater 20 is energized for a certain period of time to generate heat, and the circuit structure thereof is shown in FIG. .
That is, the coil heater 20 is connected to the timer circuit 22.
The series circuit is connected in series with lamp 1.
are connected in parallel to the

The operation of the bent type fluorescent lamp 1 thus constructed will now be described.

When the lamp is off, the ambient temperature is low, so the floating mercury inside the tube is absorbed by the auxiliary amalgams 12, 12 and 2.
1, and the mercury vapor pressure inside the tube is also low.

Then, when the power is turned on and the lamp lights up, the filament 1 installed at both ends of the bulb
1 and 11 generate heat, and these filaments 11 and 1
Arc discharge occurs within 1 hour. At this time, the auxiliary amalgams 12, 12 installed near each filament 11, 11 are heated by the radiant heat from the filaments 11, 11, and therefore release the mercury adsorbed when the light is turned off.

In addition, when the power is turned on, the timer circuit 22 is activated, and the coil heater 20 provided in the middle of the discharge path is activated.
When the coil heater 20 is energized, the coil heater 20 generates heat. Therefore, the other auxiliary amalgam 21 is heated and releases the mercury that was adsorbed when the light was turned off. At this time, in this embodiment, since the other auxiliary amalgam 21 is placed in the area of the arc (positive column) generated between the filaments 11, 11, it is also heated by this arc. That will happen.

Therefore, since the auxiliary amalgams 12, 12 and 21 release mercury at both ends and in the middle of the arc tube, the mercury vapor is quickly diffused throughout the arc tube. Therefore, the time required for the mercury vapor pressure within the bulb to reach a predetermined level and uniformity is shortened, the luminous flux rise time is shortened, and the brightness distribution of the bulb is also made uniform.

Note that the timer circuit 22 operates for a predetermined period of time after the power is turned on, and automatically stops energizing the coil heater 20 after this period of time has elapsed.

Furthermore, since the coil heater 20 is not coated with an emitter, no arc discharge occurs between the coil heater 20 and the filaments 11, 11.

In addition, if the mercury released from the auxiliary amalgam 12, 12, 21 into the discharge space is excessive,
The main amalgam 14 adsorbs mercury and controls the mercury vapor pressure within the bulb.

That is, since the main amalgam 14 is accommodated in the exhaust tube 13 of the U-shaped valve 5c located at the end, it is away from the arc, and therefore the temperature rise of the main amalgam 14 is gradual and low. Therefore, a pressure gradient is created between the mercury vapor pressure determined by the temperature of the tube wall and the mercury vapor pressure determined by the temperature of the main amalgam 14, and the main amalgam 14 draws back excess mercury. As a result, the mercury vapor pressure can be quickly controlled to an optimal state, and the characteristics become stable within a short time.

The results of an experiment regarding the above embodiment are shown in FIG. 6 and FIGS. 7A and 7B.

FIG. 6 shows a comparison of the rise speed of light output between a conventional system without any other auxiliary amalgam 21 and heater 20 (characteristics shown in broken lines) and that of the above embodiment (characteristics shown in solid lines). . From this characteristic diagram, it can be seen that in the case of the structure of the example, the optical output rises quickly, and therefore the luminous flux rise time is shortened.

FIG. 7 shows the luminance distribution according to the position of the arc tube over time after starting. FIG. 7A shows the example, and FIG.
and a conventional one that does not include a heater 20.
As can be seen by comparing these characteristics, in the above example, another auxiliary amalgam 21 was installed in the middle of the arc tube, so the luminance of the middle part of the arc tube was reduced by the release of mercury from this auxiliary amalgam 21. The brightness rises quickly, and the time it takes for the entire brightness to reach the same level is also shortened.

In the above embodiment, three U-shaped bulbs 5a, 5b, and 5c are connected by a welded part 6 as the bent fluorescent lamp 1. , or four or more U-shaped valves connected together.

When four or more U-shaped valves are connected, an auxiliary amalgam may be installed in each of the two intermediate U-shaped valves.

In addition, the present invention has auxiliary amalgam 1 at both ends.
The present invention is not limited to installing the auxiliary amalgams 2 and 12, and may be implemented only with the auxiliary amalgam 21 in the middle. In this case, it is desirable to install the main amalgam near the auxiliary amalgam 21 via a thin tube.

Further, the electric circuit that supplies current to the coil heater 20 may connect the coil heater 20 and the lighting tube 26 in series.

Further, the bent fluorescent lamp may be a W-shaped fluorescent lamp or a saddle-shaped fluorescent lamp (which becomes approximately W-shaped when unfolded).

[Effects of the invention] As explained above, according to the invention, the auxiliary amalgam is installed in the middle of the discharge path between both electrodes, and at startup, the auxiliary amalgam is heated for a certain period of time by the heater. Since mercury vapor is supplied from the auxiliary amalgam, the mercury vapor is rapidly diffused throughout the bulb. Therefore, the diffusion of mercury vapor released from the auxiliary amalgam during startup is promoted quickly, the time required for the mercury vapor pressure within the bulb to reach a predetermined pressure as a whole is shortened, and the luminous flux rise time is reduced. It has the advantage of being shorter.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 shows a bent fluorescent lamp in an expanded state, Fig. 2 is an enlarged sectional view of the middle part of Fig. 1, and Fig. 3 shows an enlarged sectional view of the middle part of Fig. An enlarged sectional view, FIG. 4 is a perspective view of the entire fluorescent lamp device, FIG. 5 is a circuit configuration diagram, FIG. 6 is a characteristic diagram showing light output rise characteristics, and FIGS. 7A and B.
7A shows the characteristic diagram of the present embodiment, and FIG. 7B shows the characteristic diagram of the conventional method. 1...Bent fluorescent lamp, 2...Base, 5
a, 5b, 5c... U-shaped bulb, 6... Fusion part, 7... Fluorescent coating, 8... Electrode mount,
9...Stem, 10...Lead wire, 11...Filament, 12...Auxiliary amalgam, 13...Exhaust tube, 14...Main amalgam, 17...Stem, 19...Lead wire, 20...Coil heater ,
21...Auxiliary amalgam, 22...Timer circuit.

Claims (1)

[Claims for Utility Model Registration] (1) A main amalgam and an auxiliary amalgam are placed in a bulb having electrodes sealed at both ends, a phosphor coating formed on the inner surface, and a curved discharge path filled with rare gas. In the accommodated bent fluorescent lamp, the auxiliary amalgam is installed in the middle of the discharge path between the two electrodes, and a heater is installed near the auxiliary amalgam to heat the auxiliary amalgam for a certain period of time at the time of startup. A bent fluorescent lamp. (2) The bent fluorescent lamp according to claim 1, which is characterized in that other auxiliary amalgams are installed near the electrodes at both ends of the bulb. (3) The bulb forming the bent discharge path has a plurality of U-shaped bulbs joined together at their ends, a stem provided at the end on the joining side, and a pair of lead wires sealed in the stem; 3. The bent fluorescent lamp according to claim 1 or 2, wherein a heater is connected to these lead wires and an auxiliary amalgam is attached to one of the lead wires.