JPS6068546A - Straight-tubular fluorescent lamp - Google Patents

Abstract

PURPOSE:To decrease the amount of a phosphor used in making a straight-tubular fluorescent lamp having a length of 830+ or -30mm. so as to reduce its cost by decreasing the diameter of the lamp to within a specified range. CONSTITUTION:The length and the tube diameter of a straight-tubular fluorescent lamp charged with a gas consisting of argon at a pressure of 1.0-3.5Torr, are adjusted to 830+ or -30mm. and 25.5+ or -2.5mm. respectively. During the ignition in a commercial frequency, this lamp has a current of 250+ or -50mA and an electric power of 16-23W. By thus adjusting the diameter of the lamp to that of a straight-tubular fluorescent lamp of a lower by one, it is possible to decrease the amount of a phosphor used. This is advantageous in terms of the cost of the lamp. When a lamp is ignited with the same current as that for a one rank higher lamp, there is a general tendency that the temperature of the tube wall excessively increases resulting in a decreased brightness and that the lamp efficiency at aroung 25 deg.C is deteriorated. However, with the lamp of this invention, it is possible to increase the lamp efficiency while reducing the cost.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application This invention relates to a straight tube fluorescent lamp used for general indoor lighting, signage lights, and the like.

Conventional technology Straight tube fluorescent lamps used for indoor lighting and signboard lights in general households, shops, and offices have a rated power consumption of 20 watts.
40 watt and 110 watt types are the mainstream. Fluorescent lamps for general lighting have different tube lengths and diameters depending on the type, and each type has stable and efficient electrical characteristics, but there are cases where there is no suitable tube length for the purpose and there are unavoidable inconveniences. There is. For example, the signboard light of a 3-shaku signboard is 3
A straight tube fluorescent lamp with a tube length close to 900 m is desired, but the 20 watt type straight tube fluorescent lamp mentioned above has a tube length of 58 m.
Since it is too short at 0fl, if you use it, you have no choice but to use two of the same lamp in combination.

In order to eliminate this inconvenience, recently we have developed a 830±30 Tsuru pipe with a pipe length of nearly 3 shaku and a pipe diameter of 3"2.5±1.5N.
The Watt straight tube fluorescent lamp has been developed and put into practical use.

This 32 Watt fluorescent lamp is designed to have a lamp current of 435 mA, maximum lamp efficiency at an ambient temperature of 25°C, and stable characteristics.

C.8 Purpose of the Invention The object of the present invention is to improve the lamp efficiency and reduce the cost of a straight tube fluorescent lamp having the same tube length as the above-mentioned 32 Watt straight tube fluorescent lamp. Another object of the present invention is to provide a straight tube fluorescent lamp suitable for high frequency lighting, which is a recent trend.

That is, one possible way to reduce the cost of fluorescent lamps is to reduce the tube diameter to reduce the amount of fluorescent material coated on the inner surface of the bulb, thereby reducing material costs. When applying this to the above-mentioned 32 watt straight tube diameter fluorescent lamp, the amount of phosphor used can be reduced by changing the tube diameter to a standard 10 watt 15 watt tube diameter, which is one rank lower than the straight tube type fluorescent lamp. It is possible. It is advantageous in terms of cost. However, simply reducing the tube diameter causes the general problem that when the lamp is operated at the same lamp current (435 mA), the tube wall temperature rises too much and the brightness decreases, resulting in poor lamp efficiency at an ambient temperature of around 25°C. occurs. The present invention aims to satisfy both of the requirements of cost reduction and improvement of lamp efficiency, and has achieved this goal.

In addition, the lighting of fluorescent lamps for general lighting is usually 50H2 or 6
This is done with dual-frequency lighting using 0H2 commercial power supply, but recently, high-frequency lighting, which is more efficient and energy saving than commercial frequency lighting, has been considered, and has been put into practical use in some cases. This high frequency lighting uses commercial frequency as high frequency (approximately 20K).
Transistors and S
CR and the like have started to have practical value because they have been put into practical use due to recent advances in semiconductor technology. However,
Fluorescent lamps for general lighting, including the above-mentioned 32 Watt straight tube fluorescent lamp, have lamp currents that maximize lamp efficiency that are generally too large for semiconductor high-frequency conversion elements and devices in high-frequency lighting circuits. This makes practical application difficult. The present invention aims to solve this problem as well, and has achieved this goal.

20 Structure of the Invention The present invention has a tube length of 830±30 fins and a tube diameter of 25.5±2.
5m, the gas filling pressure is 1.0 to 3.5 Torr with 100% argon as the filling gas, and the electrical characteristics are that the lamp current is 250 ± 50 mA and the lamp power is 16 to 23 W when lit at commercial frequency. shall be. Details will be explained below in Examples.

E, Example pipe length is s3om, pipe diameter is 25.5m, argon 100%
A white fluorescent lamp with a gas filling pressure of 2 Torr and a calcium carophosphate phosphor coated on the inner surface of the bulb, a europium-activated yttrium oxide phosphor, and a cerium and terbium-activated lanthanum phosphate lamp. 60H2 using a test ballast at an ambient temperature of 25°C for a three-wavelength fluorescent lamp blended with a phosphor and a rare earth phosphor such as a eurobim-activated barium/magnesium aluminate phosphor. Lamp current during commercial frequency lighting (m
The experimental results of lamp efficiency (I!IIl/W), lamp power (W), and lamp voltage (V) for A) are shown in the drawing.

Graph a in the drawing is a graph showing the relationship between the lamp current and lamp efficiency of a white fluorescent lamp.
It can be seen that it peaks at 0iA and decreases as it increases beyond 200m8.

Graph b in the drawing is a graph of the relationship between the lamp current and lamp efficiency of a three-wavelength band fluorescent lamp, and the lamp efficiency peaks at a lamp current of about 250 mA.
It can be seen that the temperature gradually decreases when the temperature exceeds A and becomes below A.

Therefore, the lamp current that improves the lamp efficiency for both white and three-wavelength fluorescent lamps is around 225 mA, and it has been experimentally confirmed that 250±50- is a practical range. In particular, when it exceeds 300 mA, the lamp efficiency of the white fluorescent lamp increases (decreases), and in the case of high-frequency lighting, it becomes difficult to design the semiconductor frequency conversion element and device in the high-frequency lighting circuit, making high-frequency lighting difficult.

Graph C in the drawings is a graph of the relationship between lamp current and lamp power, and graph d is a graph of the relationship between lamp current and lamp voltage.

Next, in an experiment based on the above example, when considering the lamp efficiency when the lamp current was 250 mA and the lamp was lit for 100 hours, the white fluorescent lamp was 79. 511m /V/, 84. 41! A result of m/W was obtained. For comparison, a conventional 32 watt f&light lamp with a tube length of 830 m and a tube diameter of 32.5 m has a lamp current of 435 mA.
The lamp efficiency for white fluorescent lamps was 7.
2.1j2m/W, 79.0cm with 3 wavelength range fluorescent lamp.
A result of 6βm/W was obtained. In other words, the lamp efficiency of the present invention was improved by about 10% in white fluorescent lamps and by about 6% in tri-wavelength fluorescent lamps compared to conventional products.

By the way, in the present invention, the tube diameter is limited to 25.5±2.5 fl. This means that the valve with this pipe diameter is JIS standard IOW, 1
The bulb tube diameter of a 5W rank straight tube fluorescent lamp is the same as the center value of the standard, and the T8 rank (8
/8 inch), and if the length is thinner than 23.0 m, the lamp voltage will increase, which increases the possibility of difficulty in starting, unstable discharge, and difficulty in maintaining lighting.
8. This is because if it is made thicker than On, the lamp power decreases, leading to an increase in the lamp power. In addition, when the filled gas is 100% argon, the sealed pressure is 1.0 to 3.5 Torr. If it exceeds 3 or 5 Torr, it will be difficult to start and the brightness will decrease, and if it is less than 1.0 Torr, the lamp life will be shortened. This is based on reasons that may cause inconvenience, such as shortening the term.

Effects of the Invention As described above, according to the invention, it is possible to improve the lamp efficiency of a direct-acting fluorescent lamp with a tube length of 830±30 fins. 300mA
Since it can be made as small as below, it is possible to provide a device suitable for high frequency lighting, and by providing this, the placement of the fluorescent lamp can be made easier to put into practical use. In addition, by reducing the tube diameter of a straight tube fluorescent lamp with a tube length of 830±30 m, the amount of phosphor coated on the inner surface of the bulb can be reduced, making it possible to reduce the cost of the fluorescent lamp. This is particularly important in three-wavelength fluorescent lamps that use expensive rare earth phosphors.

[Brief explanation of the drawing]

The drawings are graphs of various characteristics of a single unit example of a straight tube fluorescent lamp according to the present invention.

Claims (1)

[Claims] (11 pipe length is 830±301 layers, pipe diameter is 25.5±2.
5 m, 100% argon as the filled gas, gas filling pressure 1.0 to 3,5 Torr, lamp current 250 ± 50 mA when lit at commercial frequency, lamp power 16
A straight tube type fluorescent lamp characterized by having a power of ~23W.