JPH0660849A - Fluorescent lamp - Google Patents

Abstract

PURPOSE: To improve luminous efficiency, and delay the speed of blackening phenomenon to improve cooling efficiency in a glass tube by reducing the absorptivity of ultraviolet ray in the glass tube in the center part to be smaller than in a conventional glass tube, and controlling the rise of inside temperature in a pair of glass tubes to be wider than the conventional glass tube diameter. CONSTITUTION: In this fluorescent lamp, a diameter D2 of a fine glass tube 19 is formed smaller than a conventional glass tube diameter, so that the self- absorptivity of ultraviolet ray in the center portion can be small, in order to increase luminous efficiency. A diameter D1 of a glass tube 11 is formed wider than the conventional glass tube diameter, in order to restrain the rise in the inside temperature of the fine tube 19, to improve cooling efficiency. Blackening speed can be delayed because of the increase in the distance between a cathode 12 and the glass tube wall 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent lamp, and more particularly, to a pair of glass tubes having a wider self-absorption rate of ultraviolet rays in a central glass tube smaller than a conventional glass tube diameter, which is wider than the conventional glass tube diameter. In the above, the present invention relates to a fluorescent lamp in which not only the luminous efficiency is improved by suppressing the rise of the internal temperature, but also the speed of the blackening phenomenon is delayed to improve the cooling efficiency in the glass tube.

[0002]

2. Description of the Related Art Generally, light sources for illumination are roughly classified into an incandescent lamp system and a discharge lamp system, of which the discharge lamp system is roughly classified into a fluorescent lamp, a mercury lamp, a high-pressure sodium lamp, a halogen lamp and the like. The fluorescent lamp is mainly used as a home lighting fixture.

As shown in FIG. 5, a conventional straight tube fluorescent lamp has a base 5 attached to both ends of a hollow glass tube 1 having a length L2 and a diameter D, and a space between pins 10 is L1. It The transparent glass tube 1 is a cylindrical type having a constant tube diameter D and is coated so as to form a thin film of the phosphor 2 on the inner surface, and a base 5 of a pin 10 is provided at both ends thereof to form a double coil type tungsten filament. Cathode 3 coated with electron emitting material
And a positive electrode 4 is attached respectively. Then, mercury and argon or krypton-based glass having a pressure of several mmHg for facilitating electric discharge are sealed in a certain cylindrical glass tube 1.

The base 5 of the glass tube 1 for lighting the conventional straight tube fluorescent lamp of the finished product thus constructed
A corresponding voltage is applied between the pins 10 fixedly attached to the negative electrode 3, that is, between the negative electrode 3 and the positive electrode 4. At this time, a current flows through the filament of the negative electrode 3 in the enclosed glass tube 1 and is preheated, so that thermoelectrons are emitted.
The thermoelectrons are moved to the filament of the positive electrode 4 by the electric field and the discharge is started. The electrons 6 generated by such a discharge collide with the mercury atoms 7 of the vaporized mercury vapor due to the temperature rise in the enclosed glass tube 1, and the mercury atoms 7 are excited thereby, so that the side walls of the glass tube 1 are excited. UV light 8
Will be emitted. The ultraviolet rays 8 radiated on the side wall of the glass tube 1 coated with the fluorescent material 2 are absorbed by the thin film fluorescent material 2 and then converted into visible rays 9 to be emitted to the outside of the glass tube 1. The visible light 9 of the fluorescent lamp is obtained.

[0005]

As described above, the ultraviolet rays 8 radiated by the excitation phenomenon of the mercury atoms 7 in the glass tube 1 enclosed so as to obtain an appropriate visible ray 9 are applied to the inner wall of the glass tube 1. When the radiation distance to the stored phosphor 2 increases, self-absorption often occurs before the phosphor 2 arrives at the thin film, so that the self-absorption of the ultraviolet rays 8 in the enclosed glass tube 1 is reduced. As long as you can
The diameter D of the glass tube 1 needs to be small.

However, in order to reduce the self-absorption rate of the ultraviolet rays 8, if the diameter D alone is made smaller than the existing diameter while maintaining the entire length L2 of the glass tube 1, the phosphor 2 thinly applied to the inner wall of the glass tube 1 is heated. Therefore, the emission intensity is reduced due to the influence of the temperature characteristics of the phosphor 2. Also,
As the temperature of the phosphor 2 rises, the internal temperature of the glass tube 1 rises, so that the pressure of mercury vapor also rises. This is because if the mercury vapor pressure in the glass tube 1 becomes higher than the optimum value, a small amount of the ultraviolet rays 8 will be radiated, and a small amount of visible light 9 will reduce the luminous efficiency of the fluorescent lamp.

On the other hand, when the conventional fluorescent lamp is turned on, the glass tube 1 is attached to the filament of the negative electrode 3 at both ends of the glass tube 1 enclosed.
Since the cations in the inside collide with each other as a large energy, the electron emitting material applied to the filament of the negative electrode 3 is gradually scattered, and the electron emitting material thus scattered is around the filament of the negative electrode 3. It is adsorbed on both end walls of the glass tube 1 and appears in a blackened state. In such a state, if the lighting time is long, the blackened portion is diffused on both end walls of the glass tube 1. This causes a problem that not only the blackened portion of the glass tube 1 becomes electrically conductive and disturbs the discharge, but also the blackened portion lowers the luminous efficiency of the fluorescent lamp.

The object of the present invention is not only to reduce the self-absorption rate of ultraviolet rays in the enclosed glass tube but also to delay the rate of the blackening phenomenon at both ends of the glass tube and to enhance the cooling efficiency and the luminous efficiency in the glass tube. As the center of the glass tube can be made smaller, the glass tube having a diameter smaller than that of the conventional glass tube is welded to the glass tubes at both ends which are wider than the diameter of the conventional glass tube. An object of the present invention is to provide a fluorescent lamp capable of delaying the scattering phenomenon speed of the electron emitting material applied to the negative electrode filament by a sufficient space between the side wall of the cylinder and the negative electrode filament.

[0009]

SUMMARY OF THE INVENTION A fluorescent lamp according to the present invention comprises a pair of glass tubes having a diameter D1 in which one opening is contracted inward and the other opening is contracted in a side wall and a hole is formed in the center thereof. A base that adheres to one opening of the glass tube,
The diameter D of the glass tube is fitted and welded to the hole of the glass tube.
It has a diameter D2 smaller than 1 and is composed of a glass capillary tube having an inner wall coated with a thin film phosphor.

[0010]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a straight tube type fluorescent lamp according to an embodiment of the present invention. The fluorescent lamp of the present invention is designed to have a small self-absorption rate of ultraviolet rays in the central portion in order to improve luminous efficiency. With a length of L6, the diameter D of the glass capillary 19
2 is formed to be smaller than the diameter of the conventional glass tube, and the glass tube 19
A glass tube 1 having a predetermined length L5 and a diameter D1 wider than a conventional glass tube diameter D so as to suppress an internal temperature rise.
By welding the glass capillary tube 19 to the glass tube 11 at the end of 1, the glass tube 11 has a large space and a large wall area, so that the cooling efficiency of the glass tube 19 can be improved.

Further, according to the present invention, as shown in FIG. 2, a sufficient space can be formed between one side wall C1 of the glass tube 11 and the negative electrode 12, and electron emission applied to the filament of the negative electrode 12 can be achieved. The speed of the material scattering phenomenon can be delayed. This is because the speed of the scattering phenomenon is Ve / P · D (where Ve is the negative electrode drop voltage, P is the gas pressure, and D is the distance between the negative electrode) and is inversely proportional to the distance between the negative electrode 12 and the glass tube 11 wall. Therefore, the distance between the negative electrode 12 and the wall of the glass tube 11 becomes wider, and the blackening phenomenon speed can be delayed.

The glass tube 11 shown in FIG. 2 is a cylindrical glass tube having a diameter of D1 and larger than the D diameter of the conventional glass tube 1 shown in FIG. Pin 1
The base 17 on which 8 is formed can be easily fitted. Also,
The other opening of the glass tube 11 is contracted by the side wall C1 and a hole C3 into which the above-mentioned glass capillary tube 19 can be inserted is formed in the center thereof, so that the glass capillary tube 19 can be easily welded around the hole C3. The outer edge is formed in a B2 shape. The edge B2 of the glass tube 11 and the glass capillary 1
9 are overlapped and the joint portion is firmly welded.

As shown in FIG. 3, the glass tube 11 is inserted and welded on both sides of a glass capillary tube 19 having a diameter D2 smaller than the conventional fluorescent lamp diameter D, and the glass tube 11 and the both side glass tube 11 are welded together. The inner wall is formed by applying a conventional thin film phosphor 20. In this manner, the base 17 is adhered to one opening of the glass tube 11 with the glass tubes 11 welded on both sides of the glass capillary tube 19, and the negative electrode 12 (or the positive electrode 13) is formed as in the conventional fluorescent lamp. And the exhaust pipe 14 is attached. As shown in FIG. 2, the stems 16 of the both electrodes 12 and 13 are made by widening the wing portion of the portion A and welding with a stem wider than the conventional stem, and then the glass capillary tube 19 and both sides welded in the same manner as the conventional one. The inside of the glass tube 11 is evacuated to fill mercury and an inert gas, and the bases 17 are adhered to the glass tube 11 to complete the fluorescent lamp according to the present invention.

Therefore, the fluorescent lamp of the present invention has a total length of L2 (where L2 = 2L5 + L6, and L2>L6> 2).
At L5, the glass tube 11 has the length of L5 and most of the blackened portion is present. It is the same as the total length L2 of the conventional fluorescent lamp, and the spacing between the pins 18 of the base 17 is L3 and the conventional pin 10 is used. Since it is the same as the distance L1, it can be replaced with a conventional lighting fixture using a fluorescent lamp.

The space L4 between the filament of the negative electrode 12 and the side wall C1 in the enclosed glass tube 11 is as shown in FIG. 2 from the assembled state of the fluorescent lamp of the present invention as described above. It is formed wider than the filament of the electrode 12 and the glass tube wall C2, and the speed is delayed due to the scattering phenomenon of the electron emitting material generated in the conventional filament of the negative electrode 12.

The fluorescent lamp of the present invention is a straight tube type glass capillary tube 19
However, the present invention is not limited to this, and as shown in FIGS. 4 (A) and 4 (B), the glass capillary tube 19 may be formed into a ring shape or a U shape and welded to the glass tube 11 for use. .

A lighting operation of the fluorescent lamp of the present invention having the above-mentioned structure will be described.

The negative electrode 12 between the pins 18 on the base 17 of the glass tube 11 for lighting the fluorescent lamp of the present invention.
A corresponding voltage is applied between the positive electrode 13 and the positive electrode 13, but this causes the same electrical phenomenon as in a conventional fluorescent lamp, and detailed description thereof is omitted and the enclosed glass capillary tube 19 is omitted.
Only the operations that occur in the glass tubes 11 on both sides will be described.

First, due to the electrical phenomenon of the fluorescent lamp, the self-absorption rate of ultraviolet rays is reduced in the tube enclosed by the glass capillary tube 19 having a diameter D2 smaller than the conventional glass tube diameter, so that the light emitting effect is improved. However, the small diameter is D2
The heat generated by the phosphor 20 applied to the wall of the glass capillary 19 is conducted in the glass tube 11 having a diameter D1 wider than the diameter of the conventional glass tube welded on both sides of the glass capillary 19. Therefore, this large surface area enhances cooling efficiency. The enclosed glass tube 11 and glass tube 19 on both sides are enclosed.
As described above, the internal pressure of the internal gas of the glass tube 11 on both sides of the gas pressure is large so that the pressure adjusting effect can be enhanced.

The radiation scattering phenomenon generated from the filament of the negative electrode 12 provided in the enclosed glass tube 11 is caused by the space inside the glass tube 11 having a diameter D1 wider than the conventional glass tube diameter. Since it is wide, the time can be delayed and the blackening phenomenon that occurs around the filament of the negative electrode 12 is caused. Therefore, the fluorescent lamp of the present invention gradually reduces the life due to the blackening phenomenon in the glass tube 11 and the decrease in the luminous efficiency due to the blackening phenomenon.

Further, since the gap between the filament of the negative electrode 12 inside the enclosed glass tube 11 and the inner wall C2 of the tube is formed wide, heat loss due to heat radiation at the negative electrode 12 is reduced. Since the temperature rise of the glass tube 11 having the wide diameter D1 is reduced, the thermal efficiency of the fluorescent lamp is improved. Therefore, the fluorescent lamp of the present invention has a glass tube 19 at the center.
Since the self-absorption rate of ultraviolet rays is reduced inside and the rise of the internal temperature can be suppressed by the glass tubes 11 at both ends, the luminous efficiency is increased and the speed of the blackening phenomenon is also delayed.

[0023]

As described above, according to the present invention, not only the self-absorption rate of ultraviolet rays is reduced in the enclosed glass tube, but also the rate of the blackening phenomenon is delayed at both ends of the glass tube to reduce the rate of blackening. In order to improve the cooling efficiency and the luminous efficiency, the central portion of the glass tube is smaller than the conventional glass tube diameter, and the glass tube is welded to the glass tubes at both ends wider than the conventional glass tube diameter. A fluorescent lamp capable of delaying the scattering phenomenon speed of the electron emitting material applied to the negative electrode filament by a sufficient space between the side wall of the glass tube and the negative electrode filament while suppressing the internal temperature rise. I will provide a.

The present invention is not limited to the above-mentioned contents, but includes all the modifications, changes and improvements included in the contents described in the claims without departing from the phenomenon and principle of the present invention.

[Brief description of drawings]

FIG. 1 is a diagram showing a straight tube fluorescent lamp according to an embodiment of the present invention.

FIG. 2 is an exploded cross-sectional view of main parts of the fluorescent lamp shown in FIG.

FIG. 3 is an exploded perspective view of essential parts of the fluorescent lamp of the present invention.

FIG. 4 is an outline view showing a ring-shaped and U-shaped fluorescent lamp of another embodiment of the fluorescent lamp of the present invention.

FIG. 5 is a diagram showing an internal structure of a conventional straight tube fluorescent lamp.

[Explanation of symbols]

 1 glass tube 2,20 phosphor 3,12 negative electrode 4,13 positive electrode 5,17 base 6 electron 7 mercury atom 8 ultraviolet ray 9 visible light 10,18 pin 11 glass tube 14 exhaust pipe 15 lead wire 16 stem 19 glass tube

Claims (3)

[Claims] 1. A pair of glass cylinders having a diameter D1 in which one opening is shrunk inward and the other opening is shrunk by a side wall, and a hole is formed in the center thereof, and the glass tube is bonded to the one opening. It is composed of a base and a glass capillary tube fitted and welded to the hole of the glass tube, having a diameter D2 smaller than the diameter D1 of the glass tube and having an inner wall coated with a thin film phosphor. Fluorescent lamp to do. 2. The fluorescent lamp according to claim 1, wherein a stem having an enlarged wing portion is welded to one opening of the glass tube adhered to the base. 3. The fluorescent lamp according to claim 1, wherein the glass thin tube is formed in a straight tube type, a ring type or a U shape.