JPH0388255A - Fluorescent lamp - Google Patents

Abstract

PURPOSE:To unify brightness in connection end parts of a plurality of bulbs to be connected to a connection member by making a plane center of gravity of a discharge hole of a connection member decentralized on the outer peripheral side than the cross section peripheral center of gravity of the bulb. CONSTITUTION:Since a positive column passes round the axes of the center of gravity Oa, Ob of both bulbs 21, 22, a discharge path 27 is formed as shown by a broken line of the illustration. Then, in the respective connection terminal parts 21b, 22b of the respective bulbs 21, 22 the positive columns enter a metal cab 23 from the respective axes of the center of gravity Oa, Ob after being bent outside so as to pass through the respective centers Ox, Oy of the respective discharge holes 23d, 23e positioning on the outer peripheral side than these while being here bent almost in a U-shape so that the positive columns of the respective bulbs 21, 22 are integrally connected in the U-shape. In the respective connection end parts 21b, 22b of the respective bulbs 21, 22, the positive columns are deflected to the outside from their axes of the center of gravity. Brightness in the inner and outer peripheral parts in these connection terminal parts 21b, 22b can be therefore unified.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention relates to a fluorescent lamp in which a plurality of straight or inverted U-shaped bulbs are integrally connected by a metal cap or the like. In particular, the present invention relates to a fluorescent lamp with an improved connecting member such as a metal cap.

(Prior Art) A conventional inverted U-shaped fluorescent lamp 1 shown in FIG. 4 is formed by bending a single glass bulb having a flattened cross section such as an oval axis cross section into an inverted U shape. However, in this fluorescent lamp I, the positive column 3 formed between the pair of left and right electrodes 2a and 2b in the figure was deviated toward the inner circumferential side at the U-shaped bent portion 4 thereof.

For this reason, while the UV (ultraviolet rays) intensity is high at the inner circumferential portion of the bent portion 4, the UV intensity is low at the outer circumferential portion, and there is a difference in brightness between the inner circumferential portion and the outer circumferential portion.

Therefore, in order to solve this problem, we
Generally speaking, in the fluorescent lamp 5 disclosed in Publication No. 358, when the cross-sectional shape of the bulb is circular, the sunlight column passes through approximately the center of the bulb, whereas when the cross-sectional shape of the bulb is flat, it passes approximately through the center of gravity. Focusing on this, a constricted portion 6 is provided on the inner circumferential side of the bent portion 4 of the U-shaped fluorescent lamp 1 shown in FIG. It is eccentric to the outer circumferential side from the center of the cross section of the straight part.

As a result, the axial center portion of the bent portion 4 near the outer periphery is passed through the positive column 3, and brightness at the inner and outer periphery portions of the bent portion 4 is made equal.

However, in such a fluorescent lamp 5, although it is possible to equalize the brightness at the inner and outer circumferences of the bent portion 4,
There is a problem in that coating unevenness occurs in the fluorescent film applied to the inner circumferential surface of the bent portion 4.

That is, in the case of the fluorescent lamp 5, when the glass bulb is bent into an inverted U shape as shown in FIG. 5, and then the phosphor is applied to the inner peripheral surface, the phosphor is There are areas 7 where the color is uniformly applied, dark areas 8 and thin areas 9, and uneven coating occurs.

In addition, in the fluorescent lamp 5, after coating the inner circumferential surface of the straight part of the glass bulb with phosphor, an inverted U-shape is applied as shown in FIG.
When molded into a letter shape, there is a problem in that the phosphor film sinks into the bulb, reducing the strength of the bulb.

On the other hand, the fluorescent lamp 10 shown in FIG.
This is described in Publication No. 843.

This 10 has both connecting ends 11a of, for example, two straight glass bulbs 11 and 12 having a flat cross section such as an oval shape.
, 12a, a metal cap 1 which is a connecting member.
For example, an inverted U-shaped discharge path 1
4 is formed.

This fluorescent lamp 10 has a pair of left and right electrodes 15a, 15.
A high-frequency lighting circuit 17 having a high-frequency oscillator 16 is electrically connected to b, and high-frequency lighting is performed to achieve high brightness and high efficiency.

The metal cap 13 is constructed as shown in FIG. 8, which shows the upper and lower sides of the metal cap 13 being turned upside down.
3b is fitted and fixed inside to form an airtight seal.

As shown in FIG. 7, the upper lid 13b has, for example, two connecting ends 11a of fluorescent lamps 11 and 12 each having a flat cross section.
The bulbs 12a are fixed in an upright state with frit glass or the like, and discharge holes 13c and 13d are formed in alignment with the axis of each bulb 11.12, respectively.

Furthermore, annular rising side walls 13e and 13f are provided protrudingly on the opening peripheries of these discharge holes 13c and 13d, respectively.
In FIG. 8, 13g is an exhaust pipe that exhausts the inside of the valves 11 and 12 and the metal cap 13.

The metal cap 13 is coated with an insulating film such as a glass film on at least its entire inner peripheral surface, and is electrically connected to a high frequency lighting circuit 17 as shown in FIG. It is configured as an auxiliary electrode to which a starting voltage and a lighting maintenance voltage are sometimes applied from the high frequency lighting circuit 17.

(Problem to be Solved by the Invention) However, in the conventional fluorescent lamp 10 shown in FIG.
The planar center of the bulbs 11.12 almost coincides with the axes of both bulbs 11.12, and the cross-sectional shape of each bulb 11.12 is a flat shape such as an oval. Similarly, the curved portion 10a of the discharge path 14 inside the metal cap 13 is deviated so that the discharge path 14 approaches the inner circumference side.

For this reason, both bulbs 1 whose discharge paths 14 are deviated toward the inner circumferential side
At both connection ends 11a and 12a of 1.12, the UV intensity (ultraviolet light intensity) is higher on the inner circumference side, but lower on the outer circumference side, and the brightness is brighter on the inner circumference side and darker on the outer circumference side. There is a problem that this difference in brightness occurs.

Therefore, the present invention has been made in consideration of the above circumstances, and its purpose is to provide a fluorescent lamp that can equalize the brightness at the connecting ends of a plurality of bulbs connected to a connecting member. be.

[Structure of the Invention] (Means for Solving the Problems) The present invention solves the problem of the conventional fluorescent lamp 10 shown in FIG. This was done by focusing on the fact that the plane centers of the discharge holes 13c and 13d coincide with each other, and are constructed as follows.

That is, in the present invention, each connecting end of a plurality of bulbs arranged in parallel is fixed to a connecting member having a plurality of discharge holes communicating with each of these connecting ends, and a discharge path in this connecting member is connected. In the fluorescent lamp in which the discharge paths in each bulb are integrally connected to each other and a bent portion is formed in the discharge path, the connecting member is arranged such that the planar center of gravity of the discharge hole is set to be lower than the cross-sectional center of gravity of the bulb. It is characterized by being eccentric towards the outer periphery.

(Function) The center of gravity of the planar shape of each discharge hole of the connecting member is eccentric to the outer circumferential side with respect to the axis of each bulb.

Therefore, the discharge path in the connection end of each bulb that is close to these discharge holes is formed on the outer peripheral side of the axis of the bulb.

For this reason, at the connection end of each bulb, it is possible to prevent the positive column passing through the internal discharge path from shifting toward the inner circumference.

Therefore, according to the present invention, it is possible to prevent the positive column at the connection end of each bulb from being deviated toward the inner circumference and to cause a difference in brightness between the inner and outer circumferences, and to equalize the light distribution. I can do it.

(Example) Examples of the present invention will be described below based on FIGS. 1 to 3.

FIG. 1 is a perspective view showing the overall configuration of an embodiment of the present invention.
Book straight valve 21.22 with metal cap 2
It is installed on top of 3.

Each bulb 21, 22 has a straight glass bulb body 21a with a flattened cross section, such as an oval shape.

A pair of left and right electrodes 24a and 24b are respectively sealed at the upper end of 22a in the figure, and a pair of left and right caps 25a and 25b are externally fitted and fixed on the outer periphery of the electrode sealed ends.

Each bulb body 21a, 22a has a fluorescent film coated on its inner circumferential surface over almost its entire length.

On the other hand, the entire metal cap 23 is made of Fe-42%.
The main body 23a is an elongated cylindrical body 23a made of this alloy, and the upper cover 23c in the form of an elongated disk is fitted into the upper flange 23b of the main body 23a to form an air-tight seal. It's sealed.

The upper lid 23c is formed of the alloy into a substantially oval shape,
Connection end 21b of each valve 21.22.

For example, circular discharge holes 23d and 23e communicating with 22b are formed, respectively.

The center of gravity of these discharge holes 23d and 23e, that is, the center Ox
, Oy is the center of gravity axis 0@ of each bulb 21.22 communicating with these discharge holes 23d and 23e, respectively.

The center of gravity axis O
a and Ob are set on the upper lid 23c inside the outer periphery of each of the discharge holes 23d and 23e.

Each of the centroid axes Oa and Ob forms a central axis of a discharge path through which a positive column generated between the pair of electrodes 24a and 24b passes.

However, each discharge hole 23d of the metal cap 23.

Since each center Ox, Oy of 23e is eccentric to the outer circumferential side from each center of gravity axis Oa, Ob, each valve 21.22
At each connection end 21a, 22b, the discharge path is deflected to the outer circumferential side, and then each discharge hole 23d,
23e each center Ox.

It passes through Oy and is bent into a U-shape within the metal cap 23.

That is, each connecting end 21b, 22 of each valve 21.22
In b, the discharge path through which the positive column passes is slightly deviated toward its outer circumference, so that each connection end 21
b, 22b to the inner periphery side, it is possible to prevent brightness and darkness from occurring on the inner and outer peripheries, and to equalize the brightness.

Note that the reference numeral 26 in FIG. 1 is an exhaust pipe, and this exhaust pipe 2
The air inside both valves 21 and 22 and the metal cap 23 is exhausted through the valve 6, and after the exhaust, mercury and rare gas are filled in. After this filling, the air is pinched off with a required pitch tool. .

Next, the operation of this embodiment will be explained.

Between the pair of electrodes 24a and 246 of both valves 21 and 22,
For example, when a required high frequency voltage is applied from a high frequency lighting circuit (not shown), a discharge occurs between the pair of electrodes 24a, 24b, and a positive column is generated.

This column of sunlight is the center of gravity axis of both bulbs 21 and 22, which is 0! .

Since it passes around the ob, the discharge path 2 is the path of the positive column.
7 is formed as shown by the broken line in FIG.

And each connection end 21b, 22 of each valve 21.22
In b, it is bent toward the outer circumferential side from each center of gravity axis Oa, Ob so as to pass through each center Ox, Oy of each discharge hole 23d, 23e located on the outer circumferential side, and then enters the metal cap 23, where it enters the metal cap 23. Each valve 21. is bent into a substantially U-shape.
22 positive pillars are connected together in a U-shape.

Therefore, according to this embodiment, at each connection end 21b, 22b of each bulb 21, 22, the positive column is aligned with its center of gravity axis Oa.
, Ob is deviated toward the outer periphery, so that it can be prevented from deviating toward the inner periphery.
It is possible to equalize the brightness of the inner and outer peripheral portions in b.

In addition, in the above embodiment, the connection end 2 of each valve 21, 22
Although the case where 1b and 22b are fixed onto the upper lid 23c of the metal cap 23 with frit glass has been described,
The present invention is not limited to this, but may be configured so that the metal cap 23 made of metal is heated by high frequency induction using a high frequency heating coil 30 as shown in FIG.

That is, in this embodiment, each valve 2 in contact with the upper lid 23C of the metal cap 30 is heated by high-frequency induction heating of the metal cap 23 by the high-frequency heating coil 30.
1.22 connection end 21b.

22b is heated and melted. Thereafter, by cooling and solidifying these, each of the connecting ends 21b and 22b is fixed on the upper lid 23c of the metal cap 23 in an upright state.

However, in this case, as shown in Figure 3, each valve 21.2
The lower end portions 21c, 2 in the figure of the connection ends 21b, 22b of 2
2c, a required width of the fluorescent film is removed in advance, and when each connecting end 21b, 22b is heated and melted, the fluorescent film is removed from each connecting end 21.
b, to prevent melt from penetrating into the glass of 22b.

According to this, the frit glass is attached to each bulb 21.22.
Since the process of coating the connecting ends 210, 22c of the metal cap 23 and the upper lid 23c of the metal cap 23 is not necessary, each valve 2
The work of fixing 1.22 and the metal cap 23 becomes easier.

〔Effect of the invention〕

As explained above, in the present invention, since the planar center of gravity of each discharge hole of the connecting member that connects the discharge paths of a plurality of bulbs is eccentric to the outer circumferential side than the cross-sectional center of gravity of these bulbs, the discharge Since the positive column passing through the connection end of each bulb on the periphery of the hole is deflected toward its outer circumference, it is possible to prevent it from shifting toward its inner circumference.

Therefore, according to the present invention, the positive column at the connection end of the bulb at the opening periphery of each discharge hole of the connecting member is deflected to the inner circumferential side, and a difference in brightness occurs between the inner and outer circumferences. It is possible to prevent this, and it is possible to equalize the brightness of the connection end.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the overall configuration of an embodiment of the fluorescent lamp according to the present invention, FIG. 2 is a plan view of the top cover of the connecting member shown in FIG. 1, and FIG. A perspective view showing another example of fixing the connecting end of the valve to the metal cap,
Figures 4 and 5 are front views of conventional fluorescent lamps;
The figure is a schematic vertical cross-sectional view showing uneven coating of the fluorescent film of the conventional fluorescent lamp shown in Fig. 5, Fig. 7 is a configuration diagram of another conventional fluorescent lamp, and Fig. 8 is the metal cap shown in Fig. 7. FIG. 20...Fluorescent lamp, 21.22...Bulb, 21
b, 22b...connection end, 23...metal cap (connecting member), 23d, 23e...-discharge light, 24a. 24b...Pair of electrodes, Oa, Ob...Gravity center axis, O
x. Oy...center. Figure 2 Figure 4 Figure 5 Figure 6 Figure 8

Claims (1)

[Claims] Each connecting end of a plurality of bulbs arranged in parallel is fixed to a connecting member having a plurality of discharge holes communicating with these connecting ends, and the inside of each of the bulbs is connected through a discharge path in this connecting member. In a fluorescent lamp that integrally connects two discharge paths with each other and forms a bent portion in the discharge path, the connecting member makes the planar center of gravity of the discharge hole eccentric to the outer circumferential side than the cross-sectional center of gravity of the bulb. A fluorescent lamp that is characterized by