JPH1069889A - Variable color fluorescent lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a variable color fluorescent lamp, ensuring a life utilizable for main illumination, obtainable in the same light color even a peripheral condition is changed, less in the fluctuation of the light color in a peripheral direction, and big in mechanical strength when manufactured and used. SOLUTION: An external tube 1 has a tubular state, a phosphor having a color temperature of 2,800K is applied to the inner side of the external tube 1, both the ends of it are sealed by end plates 6a and 6b, and electrodes 4a, 5a, 4b, and 5b are provided on the end plates 6a and 6b. A rare gas and mercury vapor are sealed in the external tube 1. An inner tube 2 has spiral structure and is arranged in the external tube 1, and a blue-green phosphor having a chromatically of (0.248 and 0.346) and a phosphor having a color temperature of 2,800K, are applied t the inner surface and the outer surface, respectively. A pair of electrodes 5a and 5b are arranged in the vicinity of both the end parts of the internal tube 2 inside, and the inner tube 2 is fixed by internal tube supporting plates 3 so that the lower point of the spiral structure can abut on the inner surface of the external tube 1 at every one turn.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable color fluorescent lamp capable of changing the light color of a light source.

[0002]

2. Description of the Related Art Conventionally, many lamps for changing the light color of a light source have been proposed. These lamps can be roughly divided into two types, that is, by changing the energy of electrons in discharge plasma to change the ratio of excited species. It is divided into two types: one that attempts to change the color, and one that provides several types of discharge paths and switches them to emit light, or changes the light emission ratio to change the light color. However, the former has poor color rendering properties due to the use of the emission color of atoms and is difficult to use as main illumination, and the latter is generally used as main illumination.

The variable color fluorescent lamp disclosed in Japanese Patent Application Laid-Open No. Sho 61-42852 has one outer tube and two inner tubes, both ends of which are sealed by stems. In the formed airtight space, a rare gas and mercury of several Torr are sealed to form a discharge space. Then, three electrodes are arranged on one stem so as to be located at the vertices of an equilateral triangle, and a common electrode is arranged on the other stem. Further, the two inner tubes disposed in the hermetic space of the outer tube are hermetically sealed at one end around one electrode so that discharge does not cause crosstalk between adjacent electrodes. The other end on the electrode side is open to an airtight space formed by the outer tube. Further, a blue phosphor is applied to the inner surface of the outer tube, and a red phosphor and a green phosphor different from the phosphor of the outer tube are applied to the inner surface of the inner tube.

[0004] The variable color fluorescent lamp thus configured is lit by direct current, and controls the discharge in three discharge paths formed between the common electrode and the three electrodes independently of each other, thereby controlling the discharge. By changing the intensity of the luminescent color, a desired light color is obtained as a whole.

Further, the variable color fluorescent lamp disclosed in the microfilm of Japanese Utility Model Application Laid-Open No. 55-137664 has an outer tube in which one phosphor is coated on the inner surface and an inner tube in which a different phosphor is coated on the inner surface. , And electrodes are provided inside the respective ends.

[0006] This variable color fluorescent lamp first has a number inside.
A rare gas and mercury of Torr are sealed to produce an inner tube without a base at the end, and the inner tube is a stem that seals both ends of the outer tube. Into the fitting hole of the stem provided with
It is manufactured by sealing a rare gas and mercury of Torr and providing caps for electrodes in the outer tube and electrodes for the inner tube at both ends of the outer tube. That is, the outer tube and the inner tube have completely separate hermetic spaces, respectively, and this variable color fluorescent lamp is configured by mechanically connecting two independent lamps.

In the variable color fluorescent lamp thus constructed, the outer tube and the inner tube form completely separate hermetic spaces, and the discharge inside the outer tube and the inner tube can be controlled independently. Therefore, a desired light color is obtained as a whole by controlling the outer tube and the inner tube independently and changing the intensity of each emission color.

[0008]

However, in the variable color fluorescent lamp disclosed in Japanese Patent Application Laid-Open No. Sho 61-42852, a so-called cataphoresis phenomenon occurs when a high-output type is used because it is a DC discharge. There is a problem, when lighting with AC, the common electrode becomes too hot at the time of anode cycle, shortens the life,
There was a problem that it could not be used as main lighting.

In the variable color fluorescent lamp disclosed in the microfilm of Japanese Utility Model Publication No. 55-137664, two outer lamps and two inner lamps each having a completely independent hermetic space are mechanically connected to each other. The outer tube and the inner tube form completely separate hermetic spaces, so that the mercury vapor pressure inside the outer tube and the inner tube is reduced. Is determined independently of each other, and even when dimming control is performed under the same conditions, the mercury vapor pressure of the outer tube and the inner tube changes differently with the change in the ambient temperature where the lamp is installed. Therefore, it is difficult to obtain the same light color. Further, there is a problem that the light color changes in the circumferential direction of the outer tube depending on the position of the inner tube with respect to the outer tube.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to secure a life span usable as main illumination and to maintain the same light even when ambient conditions change. It is an object of the present invention to provide a variable color fluorescent lamp which is easy to obtain a color, has less variation in light color in a circumferential direction, and has a large mechanical strength at the time of manufacture and use.

[0011]

According to the present invention, in order to solve the above-mentioned problems, metal vapor is sealed in an airtight space formed by hermetically sealing both ends, and a phosphor is coated on the inner surface. And an inner tube, which is accommodated in the outer tube and is coated with a phosphor different from the phosphor on the inner surface, and disposed at both ends of the outer tube and the inner tube. A variable color fluorescent lamp comprising an electrode, and causing independent discharge in each of the outer tube and the inner tube, and wherein the space in the inner tube forms the same hermetic space as the space in the outer tube. According to the present invention, the inner tube has a spiral structure, and a lower point of the inner tube of the spiral structure abuts on the inner surface of the outer tube every turn. The life span of the main lighting While it is easily obtained the same light color even when the ambient conditions change, less circumferential direction of the light color variations, and can provide a large variable color fluorescent lamp of mechanical strength during manufacturing and during use.

For a variable color fluorescent lamp having a total lamp length exceeding 1 m, it is desirable that the length of one turn of the spiral structure be 1/8 to 1/10 of the total lamp length.

[0013]

FIG. 1 shows an embodiment according to the present invention. This variable color fluorescent lamp comprises an outer tube 1, an inner tube 2, an inner tube support plate 3, and electrodes 4a, 4b, 5a, and 4a. 5b.

The outer tube 1 is made of, for example, glass, which is a light-transmitting member, and is formed in a cylindrical shape having an inner diameter of about 30 mm and a length of about 1200 mm, and has a fluorescent material (shown in FIG. Is applied. Further, both ends of the outer tube 1 are sealed by end plates 6a, 6b.
6b are electrodes 4a, 5a and electrodes 4b, 5b, respectively.
Is provided. In the airtight space inside the outer tube 1, several To
A rare gas of rr and mercury vapor which is a metal vapor are sealed.

The inner tube 2 is made of a light-transmitting member, for example, glass, like the outer tube 1, and has a spiral structure.
It is arranged inside the outer tube 1. The inner pipe 2 has an outer diameter of 12m
m cylindrical body with a winding inner diameter of 5 mm, length per turn of 15
A blue-green phosphor (not shown) having a chromaticity of (0.248, 0.346) on the inner surface and a phosphor applied to the outer tube 1 on the outer surface. A phosphor (not shown) having the same color temperature of 2800K is applied. A pair of electrodes 5 is provided near both ends in the inner tube 2.
a, 5b are provided. Further, the inner tube 2 is fixed by the inner tube support plate 3 so that the lower point of the spiral structure comes into contact with the inner surface of the outer tube 1 every turn. The space in the inner tube 2 is configured to form the same hermetic space as the space in the outer tube 1.

In the variable color fluorescent lamp thus constructed, as shown in FIG. 2, the outer tube 1 and the inner tube 2 are provided with a dimming device 7,
The lights are turned on in parallel via the respective LEDs 8 and light control is performed independently of each other, so that a desired light color can be obtained. In this embodiment, a color temperature of 2800 K was obtained when only the outer tube 1 was turned on, and a color temperature of 6000 K was obtained when the outer tube 1 and the inner tube 2 were turned on simultaneously.

Further, since the space in the inner tube 2 is configured to form the same hermetic space as the space in the outer tube 1,
The same light color can be easily obtained even when the ambient conditions change, and there is little variation in the light color in the circumferential direction.

[0018]

According to the present invention, as described above, the inner tube has a spiral structure, and the lower point of the inner tube of the spiral structure comes into contact with the inner surface of the outer tube every turn. As long as the service life that can be used as the main lighting is ensured, it is easy to obtain the same light color even if the surrounding conditions change.
It is possible to provide a variable color fluorescent lamp that has less variation in the light color in the circumferential direction and has high mechanical strength during manufacture and use.

[Brief description of the drawings]

FIG. 1 is a simplified diagram showing one embodiment of a variable color fluorescent lamp according to the present invention.

FIG. 2 is a block diagram of a lighting circuit of the variable color fluorescent lamp according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 outer tube 2 inner tube 2 3 inner tube support plate 4a, 4b, 5a, 5b electrode 6a, 6b end plate 7, 8 dimmer

Claims (2)

[Claims] An outer tube having a metal vapor sealed in an airtight space formed by hermetically sealing both ends and a phosphor applied to an inner surface thereof, and an outer tube housed in the outer tube. An inner tube in which a phosphor different from the phosphor is applied to the inner surface, and electrodes disposed at both ends of the outer tube and the inner tube, wherein the outer tube and the inner tube are independent of each other. And a variable-color fluorescent lamp configured such that the space inside the inner tube forms the same hermetic space as the space inside the outer tube, wherein the inner tube has a spiral structure. The lower point of the inner tube is 1
A variable color fluorescent lamp characterized in that it comes into contact with the inner surface of the outer tube every turn. 2. The length per turn of the spiral structure, for a lamp whose total length exceeds 1 m,
2. The variable color fluorescent lamp according to claim 1, wherein the total length of the lamp is 1/8 to 1/10.