JPS6212052A - Fluorescent lamp - Google Patents

Abstract

PURPOSE:To reduce the size of high output fluorescent lamp while to uniform the ambient brightness distribution by arranging five foot sections of the three U-shaped light emission tubes around the remaining foot section to form a regular pentagon then communicating through discharge path. CONSTITUTION:In three U-shaped light emission tubes 6-8 having two foot sections 6a, 6b, 7a, 7b and 8a, 8b respectively, five foot sections 6a, 6b, 7a, 7b, 8a are closely arranged around the remaining foot section 8b to form a regular pentagon while respective tube 6-8 is fixed on circular ceramic endboard 4. Discharge current will flow in the order of electrode 3a, light emission tube 6, a communicating section 9, light emission tube 7, communicating section 9, light emission tube 8 and the electrode 3b or in reverse order thus to light respective light emission tube. Consequently, the entire size of light emission tube can be reduced while ambient brightness of lamp can be uniformed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fluorescent lamp having a plurality of U-shaped arc tubes.

[Conventional technology]

In recent years, compact fluorescent lamps called compact fluorescent lamps have been developed. Such fluorescent lamps include those that have a U-shaped arc tube further bent into a U-shape, and those that have an outer tube outside the U-shaped arc tube and have an airtight interior inside the outer tube. There is something called space. In the latter type of fluorescent lamp, a part of the arc tube is open to the outer bulb, so the mercury vapor pressure is properly controlled in the coldest part of the outer bulb, and the luminous efficiency is improved even if the arc tube is housed inside the spherical outer bulb. This type of fluorescent lamp is called a double tube type.

For example, Japanese Utility Model Application Publication No. 58-182259 discloses a double-tube type fluorescent lamp as described above, which uses multiple arc tubes in order to increase the length of light emitted from the arc tube and to make it more compact. There is something.

6 and 7 are an external view and a plan view of the fluorescent lamp shown in the above publication, in which 1 is an outer tube that forms an airtight space inside, and 2 is a plurality of tubes housed in the outer tube 1. It is an arc tube with one part open to the airtight space. 3 is an electrode provided on the arc tubes 2a and 2C, 4 is an end plate to which the arc tube 2 is attached, and 5 is a case part in which a ballast (not shown) for lighting the arc tube 2 is housed. . Incidentally, although not shown in the drawings, there is provided a communication section inside the end plate 4 for discharging between the arc tubes 2a and 2b and between 2b and 2C.

[Problem that the invention seeks to solve]

The fluorescent lamp constructed as described above uses three light emitting tubes to increase the output, and in order to widen the airtightness, the outer tube is narrower, and the spacing between the light emitting tubes 3 is wide. Therefore, there are problems such as it is difficult to miniaturize and the structure is complicated.

This invention was made in order to solve the above problems, and it is a fluorescent lamp that eliminates the need for an outer tube, has a large output, has a uniform luminance distribution to the surrounding area, and can be miniaturized. Aim to get a lamp.

[Means for solving problems]

The fluorescent lamp according to the present invention has three arc tubes bent in a U-shape, with one arc tube leg at the center and the other five arc tubes bent in a U-shape.
The legs of the arc tubes are arranged at the vertices of a regular pentagon, and the arc tubes are connected by a discharge path.

[For production]

In the fluorescent lamp according to the present invention, the arc tubes are connected by a discharge path, so that a discharge current flows from one arc tube through the discharge path to light the arc tube.

[Embodiments of the invention]

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

In FIGS. 1 and 2, reference numerals 6 and 7.8 indicate U-shaped legs 6a and 6b, each having two legs.

7a, 7b and 8a, 8b, these arc tubes are connected to the leg 8b of one of the arc tubes 8.
with the other five legs 6a and 6b at the center.

7a, 7b, and 8a are arranged close to or in contact with each other so as to form the vertices of a substantially regular pentagon, and each arc tube 6, 7.8 is mounted on a disk-shaped end plate 4 made of ceramic or the like. 3
a, 3b, electrodes 9 provided on one leg 6a of the arc tube 6 and the center leg 3a of the arc tube 8;
is a connecting portion serving as a discharge path connecting the leg portion 6b of the arc tube 6 and the leg portion 7a of the arc tube 7, and the leg portion 7b and the leg portion 8a of the arc tube 8 in series.

In the fluorescent lamp configured as described above, the discharge current flows from the electrode 3a to the arc tube 6. Communication part 99 arc tube 7. Liaison department 9
The light flows in the order of the two arc tubes 8 and the electrodes 3b or in the reverse order of the above, and each arc tube lights up.

Therefore, in the fluorescent lamp according to the present invention, the entire arc tube can be miniaturized, and the lamp luminance to the surrounding area can be made uniform.

In another embodiment of the fluorescent lamp of the present invention, as shown in FIG. 3, the outer diameter of the central arc tube leg 8b is made smaller than that of the other surrounding arc tube legs, so that the entire arc tube can be made even thinner. Can be placed in a smaller size. Furthermore, as shown in FIG. 4, by making the outer diameter of the central arc tube leg 8b larger than the other surrounding arc tube legs, the light from the leg 8b is directed not only toward the top but also toward the sides. Luminous efficiency increases because it can also emit light to the outside. Further, as shown in FIG. 5, the central arc tube leg 8b
By making the leg protrude longer than the other surrounding legs, the leg 8
The coldest part is formed at the top of b to optimize the mercury vapor pressure, and the luminous efficiency of the arc tube can be measured. This example is also applicable to those shown in FIGS. 3 and 4, and the shape of the top of the central arc tube leg may be hemispherical or other shapes.

Note that the inner diameter or outer diameter of the top of each arc tube 6 to 8 may be changed compared to the side closer to the end plate 4 (straight portion of the arc tube), and the shape of the U-shaped bent bottom may also be different from that of the embodiment. However, the present invention is not limited to this, and means for providing the coldest part for controlling mercury vapor pressure may be added. Further, although only the arc tube is shown in the embodiment, a case for a ballast may be attached, and a socket having a cap pin for supplying power to the electrode may be provided on the end plate 4. The shape of the end plate 4 may be circular, oval, or square.

In addition, in the embodiment, the arc tubes were attached to the end plate 4 and connected by the connection part 9 as a discharge path, but in order to make the arc tube airtight to the end plate 4, only the electrode part was attached, and the end of the arc tube was attached to the end plate 4. The portion may have a structure similar to the top portion of a U-shape and may be used as a discharge path of an arc tube. Alternatively, it is possible to seal only the end of the lamp where the electrode is located, as in a general fluorescent lamp, and do the same for the other arc tubes, without using end plates. Furthermore, the arc tubes 6 and 8 have a connecting portion 9 only on the leg portions 5b and 8a on one side, whereas the electrode side leg portion 6a of the arc tube 6 and one of the leg portions 3a of the arc tube 8 have a connecting portion 9.

The mechanical strength of the entire arc tube can be increased by simply melting and bonding the arc tube without forming a full discharge path with the arc tube 8b.

〔Effect of the invention〕

As explained above, according to the present invention, among the three arc tubes layered in a U-shape, one of the arc tube legs is centered on one side of the arc tube, and the other five arc tube legs are Since the arc tubes are arranged at the vertices of a regular pentagon and connected through a discharge path, it is possible to downsize a high-output fluorescent lamp, and since the arc tubes are clustered in a circle, the luminance distribution to the surrounding area is improved. This has the effect of making the arc tube uniform, making it easier to hold and handle the arc tube, and improving the strength of the arc tube.

[Brief explanation of drawings]

1 and 2 are an external view and a plan view of a fluorescent lamp according to one embodiment of the present invention, FIGS. 3 to 5 are plan views showing other embodiments, and FIGS. The figure shows an external view and a plan view of a conventional fluorescent lamp. 3a, 3b...electrode, 4...end plate, 6-8...
Arc tube, 6a, 6b, 7a, 7b
, 8 m, 8 b-leg, 9... communication part. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (5)

[Claims] (1) In a fluorescent lamp in which three arc tubes bent into a U-shape having two legs are connected in series through a discharge path, the center of the leg is one of the legs of the arc tube. A fluorescent lamp characterized in that the other five legs are arranged at each vertex of a regular pentagon. (2) The fluorescent lamp according to claim 1, wherein the other five arc tube legs surrounding one central arc tube leg are arranged so as to be close to or in contact with each other. (3) The fluorescent lamp according to claims 1 and 2, wherein one central arc tube leg is longer than the other five legs. (4) Claim 1, characterized in that the outer diameter of the central arc tube leg is larger than the outer diameter of the other five legs.
The fluorescent lamp according to any one of items 1 to 3. (5) Claim 1, characterized in that the outer diameter of the central arc tube leg is smaller than the outer diameter of the other five legs.
The fluorescent lamp according to any one of items 1 to 3.