JPH0831380A - Both base type high pressure sodium lamp - Google Patents

Abstract

PURPOSE:To provide a both base type high pressure sodium lamp, for which assembling of a light emitting tube and a lamp is easy, yield is high to be suitable for mass production, mechanical strength of the lamp against vibration is high, thus a long service life may be secured and the whole lamp can be made compact. CONSTITUTION:A emitting tube 5 structured by firmly sealing electrode supporting tubes 10a and 10b into both ends of a light transmissible aluminum tube is held in a straightway formed external tube 1 on both ends of which sealing parts are formed. This holding means if constructed in such a manner that one shut is bent in a V shape at the end part of the light emitting tube 6 via both end sealing parts of the external tube 1 and lead wires 12a, 12b are stretched on both ends of thus formed structs 11a, 11b so as to be connected to the center parts of electrode supporting tubes 10a, 10b and the tip part of the V shape part of the struct is connected to the metallic foil of the sealing and fixing part and also achieve integrate sealing thereto.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved arc tube holding structure for a double-barrel type high-pressure sodium lamp in which an arc tube is held in a straight tube-shaped outer tube, and both ends of which are caps.

[0002]

2. Description of the Related Art A conventional double-socket high-pressure sodium lamp has an arc tube holding structure as shown in FIG. In the figure, reference numeral 31 denotes an outer tube made of a quartz tube, and both ends of this outer tube 31 are sealed by crush seal portions 32a and 32b.
A metal foil 33 made of molybdenum or the like is provided on the crushed sealing portion.
The inner lead wires 34a, 34b such as a wire made of molybdenum and the outer lead wires 35a, 35b are welded to the metal foil. Further, power supply terminals 36a and 36b are fixed to the external lead wire to form a base. An arc tube 37 is housed in the outer tube 31. The arc tube 37 has a bulb 38 made of translucent alumina and a disk 39 made of ceramic at both ends.
It is configured by sealing with a and 39b. Also, the disc 39
Electrodes 40a and 40b are provided at the tips of the central portions of a and 39b.
41a, 41b made of niobium with attached electrodes
Is pierced and sealed.

Further, the inner lead wires 34a, 34 of the outer tube 31 are also provided.
An arc tube support 42a, 42b, which is substantially U-shaped, is provided at the tip of b.
Are welded together, and the lead wire 43a,
43b is stretched, and electrode supporting tubes 41a, 4 of the arc tube
It is welded so that the central portion of 1b is wound. In this way, the arc tube is mechanically and electrically held via the pair of substantially U-shaped columns at both ends in the outer tube. Further, a getter material 43 is integrally sealed to at least one sealing portion 32b in the outer tube.

[0004]

However, in the double-capped high-pressure sodium lamp having such a structure, the arc tube before the outer tube is sealed during manufacturing is held by one lead wire and molybdenum foil. As a result, the arc tube supporting structure including the arc tube may be tilted, and there is a problem that the yield of products is low. Further, there is a problem that the welding between the U-shaped column and the inner lead wire may come off or break due to vibration or the like during the lighting of the lamp, and the mechanical strength thereof is insufficient. Further, the getter material needs to be held in the outer tube in order to adsorb the impure gas. However, since the getter material is provided separately from the support column as described above, there is a problem in that an arrangement space is required and the entire lamp becomes large. .

The present invention has been made in view of the above, and by improving the arc tube supporting structure of the outer tube, the arc tube and the lamp can be easily assembled, the yield is good, and the lamp is suitable for mass production. It is an object of the present invention to provide a double-ended high-pressure sodium lamp which has a large mechanical strength against vibrations and the like and has a long life, and further can make the entire lamp compact.

[0006]

SUMMARY OF THE INVENTION According to the present invention, an arc tube having a transparent alumina tube and electrode supporting tubes sealed at both ends is held in a straight tube-shaped outer tube having sealing portions at both ends. Tena,
The holding means is formed by bending one end of the arc tube at both ends of the outer tube through both end sealing parts of the outer tube into a V-shape, and stretching lead wires at both ends of the V-shape support. It is characterized in that it is connected to the central part of the above, and the tip part of the pillar aV is connected to the metal foil of the sealing part and is integrally sealed. Further, a getter is connected to at least one end of the pillar.

[0007]

With the above construction, the tip of the V-shaped column is integrally sealed with the molybdenum foil at both ends of the outer tube without using an internal lead wire in the outer tube, which simplifies the manufacturing process. Not only can the lamp be used, but the arc tube can be supported on the central axis of the outer tube even while the lamp is in use, and the supporting strength of the column is increased so that it does not fall off. In addition, since the getter material can be attached to the tip of at least one of the columns to be integrated with the arc tube supporting structure, not only the manufacturing process can be simplified, but also the tube diameter of the lamp outer tube can be reduced. .

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing a first embodiment, in which 1 is an outer tube made of a quartz tube, and crush seal portions 2a and 2b are formed at both ends of the outer tube 1. Metal foils 3a and 3b made of molybdenum or the like are sealed in the crushed sealing portion,
External lead wire 4 such as a wire made of molybdenum for the metal foil
a and 4b are welded. Further, the power supply terminals 5a and 5b are fixed to the external lead wires to form a base. An arc tube 6 is housed in the outer tube 1. The arc tube 6 is constructed by sealing both ends of a bulb 7 made of translucent alumina with disks 8a, 8b made of ceramic. Further, an electrode support tube 1 made of niobium having electrodes 9a and 9b attached to the tips of the disks 8a and 8b at the center thereof.
0a and 10b are penetrated and sealed. Also, arc tube 6
Mercury and sodium are enclosed in the interior of the container together with xenon gas.

Such an arc tube 6 is held in the outer tube 1 via V-shaped arc tube columns 11a and 11b and lead wires 12a and 12b which are stretched between the tip ends on the opening side thereof. . The tip ends of the V-shaped columns 11a and 11b are integrally sealed to the molybdenum foils 3a and 3b of the sealing portions 2a and 2b of the outer tube 1, thereby omitting the conventional inner lead wire of the outer tube. Not only can it be done, but it can also be firmly attached by sealing a part of the column. Further, by winding the lead wires 12a and 12b around the central portions of the electrode supporting tubes 10a and 10b of the arc tube 6 or by welding them, the arc tube can be held on the central axis of the outer tube. Further, the alignment on the central axis is easy because of the V-shaped support. In this way, the arc tube is mechanically and electrically held via the pair of V-shaped columns at both ends in the outer tube. Further, a support body having a getter material 14 attached to the tip of at least one V-shaped column 11b is attached by welding or the like.

FIG. 2 shows a double-ended high-pressure sodium lamp according to the second embodiment. The same parts as those in FIG. 1 are designated by the same reference numerals and their description is omitted. The arc tube 6 is held in the outer tube 1 through substantially V-shaped arc tube supports 15a and 15b and lead wires 12a and 12b stretched between the tip ends on the opening side thereof. Since the opening side of the substantially V-shaped support is linearly formed, the getter mounting portion can be formed by extending the linear part as compared with the support of the first embodiment, and thus the manufacture thereof. Is even easier.

When the outer tube is sealed at both ends and exhausted,
Conventionally, the end of the outer tube on the side where the getter material is fixed must be sealed first, but in the present invention, one end of the outer tube is sealed and then the tip of the V-shaped support is attached. The other end of the welded getter material can be sealed, and the temperature of the sealed portion becomes high, so that the getter can be activated at the same time. For this reason, the getter can absorb a large amount of impure gas that hinders the discharge in the outer tube, and the life of the lamp is extended.

[0012]

As has been described above, the double-ended high-pressure sodium lamp according to the present invention can firmly hold the arc tube on the central axis of the straight tubular outer tube with a relatively simple structure. The advantage is that it is robust against vibrations and the like while the lamp is on. Further, since the getter material can be easily attached inside the outer tube, the impure gas inside the outer tube can be adsorbed and a long-life lamp can be obtained. Further, there are advantages that the lamp and the arc tube can be easily assembled, the yield is good, and the method is suitable for mass production.

[Brief description of drawings]

FIG. 1 is a side view of a double-ended high pressure sodium lamp according to a first embodiment of the present invention.

FIG. 2 is a side view of a double-ended high pressure sodium lamp according to a second embodiment of the present invention.

FIG. 3 is a side view showing a conventional double-ended high pressure sodium lamp.

[Explanation of symbols]

 1 outer tube 2a, 2b crushing sealing part 3a, 3b metal foil 4a, 4b external lead wire 5a, 5b power supply terminal 6 arc tube 7 bulb 8a, 8b disk 9a, 9b electrode 10a, 10b electrode support tube 11a, 11b V-shaped Supports 12a, 12b Lead wire 14 Getter material 15a, 15b V-shaped support

Claims (2)

[Claims] 1. A double-ended high-pressure sodium sodium container in which a light-emitting tube formed by sealing electrode supporting tubes at both ends of a translucent alumina tube is held in a straight tubular outer tube having sealing portions formed at both ends. In the lamp, the holding means bends one column into a V-shape at the end portion of the arc tube through the both end sealing portions of the outer tube,
Lead wires are stretched over both ends of the V-shaped support to connect to the central portion of the electrode support tube, and the tip of the support aV is connected to the metal foil of the sealing portion and integrally sealed. A double-ended high pressure sodium lamp that is characterized by stopping. 2. The double-socket high-pressure sodium lamp according to claim 1, wherein a getter is connected to at least one end of the column.