JPS59148259A - Discharge lamp - Google Patents

Abstract

PURPOSE:To improve the outside view of a discharge lamp and evenly decompose an electrode and then improve the lamp characteristics by forming a bridge section that connect together both opening ends of a U-shaped inner tube provided at the inner part of an outer tube and providing a capillary for exhaust that connects with the inner part of the outer tube on the surface of an end plate that is opposed to the bridge section. CONSTITUTION:A pair of electrodes are implanted on an end plate 2 that is made to adhere to an outside tube 1 by airtightly closing the opening of the outer tube 1 with optical permeability whose bottom is opened. Two inner tubes 4 whose one end airtightly encloses an electrode 3 and other end has an opening end that connects with the inner part of the outer tube 1 near the end plate 2 are connected together at their opening ends through a bridge section 5. In addition, a capillary 6 for exhaust sealed so as to connect with the inner part of the outer tube 1 is provided on the surface of the end plate 2 that is opposed to the bridge section 5. As a result, since the bridge section 5 receives all dropped mercury that passes through the capillary 6 for exhaust and introduces it in the inner part of the inner tube 4, the mercury that is made to adhered to the inner wall of the outer tube 1 will not damage the outside view. In addition, the electrode 3 sealed on the one end of each inner tube 4 permits the impure gas emitted from electron emission material to evenly be exhausted from the opening end of each inner tube 4 and the uneven decomposition of the electron emissive material to be also eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a discharge lamp, and more particularly to a discharge lamp having two U-shaped inner tubes arranged within an outer tube.

As disclosed in JP-A-57-61241, it is customary for this type of discharge lamp to have an exhaust thin tube arranged on the central axis of the discharge lamp. This is because the open end of the exhaust a-pipe and the open end of the exhaust a-pipe are not formed coaxially.

There was a problem in that the mercury dripped through the exhaust tube adhered to the inner wall of the outer tube, creating black stains that spoiled the appearance of the discharge lamp.

On the other hand, there is a discharge lamp disclosed in Japanese Patent Laid-Open No. 57-61242, in which the exhaust thin tube is offset from the center axis of the discharge lamp. This has a thin exhaust tube that opens both at one end of the inner tube and into the outer tube, and the center axis of the discharge lamp and the center axis of the exhaust tube #1 are necessarily offset from each other. There is. However, a discharge lamp with such a configuration still has the problem that mercury dripping through the exhaust thin tube falls into the outer tube with a probability of 50 cm, damaging the appearance of the discharge lamp.Furthermore, the inside of the inner tube -m (Because the air is exhausted from the flit, a pressure difference occurs between the "electrode" sealed at one end and the electrode close to the evacuation tube when the electron emitting material is decomposed, causing the two electrodes to become uneven. Decomposed.

This did not have a negative effect on the lamp characteristics and had some drawbacks.

This invention has been made in consideration of the above points, and includes forming a bridge section connecting the open ends of the U-shaped inner tube disposed inside the outer tube, and forming an end plate opposite to this Ia bridge section. A thin exhaust tube communicating with the inside of the outer tube is provided to improve the appearance and ensure uniform disassembly of the electrode.

It is an object of the present invention to provide a discharge lamp having the same characteristics as those described above.

Hereinafter, this invention will be explained using the drawings. FIG. 1 is an exploded perspective view of a discharge lamp showing an embodiment of the present invention.
(1) is a light-transmitting outer tube with an open bottom; (21 is an end plate made of metal or ceramic attached to the outer tube (1) to airtightly close the opening of +1; (31)゜(3) is a pair of electrodes implanted in the end plate (21, +41. +
41 has an electrode at one end +31. +31 in an airtight manner, and the other end has an open end (41) near the end plate (21) that communicates with the inside of the outer tube (1), (5) is the inner tube f41.
This is a bridge connecting the +41 open ends (41) and is formed by melting a part of the periphery of the open ends (41). (61 is a thin exhaust tube sealed to the end plate (2) surface facing the bridge portion (5) so as to communicate with the inside of the outer tube +11; +
71. (71, 471, +71 are ballasts (not shown)
These are electrode lead wires connected to electrical components such as the 1000 yen, etc., and power supply lines (not shown).

FIG. 2 is a schematic development view showing the discharge lamp of the above embodiment, and characteristically shows the positional relationship between the bridge portion (5) and the exhaust thin tube (61).

With such a configuration, the bridge portion (5).

All of the dripping mercury that has passed through the exhaust tube fGI is introduced into the inner tube (41, +41). Therefore, since no mercury falls into the outer tube (1), the mercury attached to the inner wall of the outer tube (11) is This solves the problem of damaging the appearance of the product and 1~.Also, the electrodes F3+, +31&':r, which are sealed at one end of each inner tube (4+, +41), impurity gas emitted from the electron emitting material, Open end of each inner tube f41.t4+ (4
1) will be uniformly exhausted, and non-uniform decomposition of the electron emitting substance will also be eliminated.

As explained above, this invention includes an outer tube with an open bottom;
an end plate having a pair of electrodes implanted therein and airtightly closing the opening of the outer tube;
It is disposed within the outer tube, one end encloses the electrode in an airtight manner, and the other end communicates with the inside of the outer tube near the end plate to form openings 1 to 2.
It has several U-shaped inner tubes.

By forming a bridge connecting the open ends of the inner tube and sealing a thin exhaust tube communicating with the inside of the outer tube on the end plate surface facing this bridge, mercury can be removed from inside the inner tube. This prevents mercury from adhering to the inner wall of the outer tube.
This has the effect of improving the appearance of the product, and also enabling uniform decomposition of the electron emitting material deposited on the electrode, and improving lamp characteristics.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a discharge lamp showing one embodiment of the present invention, and FIG. 2 is a schematic developed view of the discharge lamp showing one embodiment of the present invention. In the figure, (IJ is the outer tube, (2) is the end plate, (3), (
3) is an electrode, +41. (4) is the inner pipe, (5) is the bridging part, and (61 is the exhaust tube. The same reference numerals in each figure indicate the same or equivalent parts. Agent Nobu Kuzuno - 1st figure

Claims (1)

[Claims] an outer tube with an open bottom; an end plate in which a pair of electrodes are implanted and hermetically closes the opening of the outer tube; an end plate disposed within the outer tube, one end of which encloses the electrode in an airtight manner, and the other end of which is an end plate; It has a U-shaped inner tube of 2I@ which is connected to the inside of the outer tube and has a gateway in the vicinity, and a bridge section connecting the open ends of the inner tube is formed in the inner tube, and it is opposite to the bridge section between the inner tube and the inner tube. A discharge lamp characterized in that an exhaust thin tube communicating with the inside of the outer bulb is sealed on the end plate surface of the discharge lamp.