JP2000021352A - Single cap discharge lamp, shield beam device and shield beam lighting device using the same - Google Patents

Abstract

(57) Abstract: In a single-cap discharge lamp, an arc tube and an external power supply arranged along the side surface of the arc tube vibrate integrally, and the arc tube and the external power supply are connected to each other. Prevents the peeling of the joint between the external power supply and the metal foil in the arc tube, which is caused by different vibrations, and improves the durability against vibration. SOLUTION: An outer tube 8 is fixed around the outer periphery of an arc tube 1, and an external power supply 7a arranged along the outer surface of the outer tube 8 is connected to the outer surface of the outer tube 8 by a connecting means 10. I do.
When an external vibration is transmitted to the single-cap discharge lamp, the arc tube 1, the outer tube 8, and the external power supply 7a vibrate integrally, and the external power supply 7a and the metal foil 6a in the arc tube 1 are vibrated.
Peeling off of the joint portion is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-sided discharge lamp, a shield beam device using the same, and a shield beam lighting device.

[0002]

2. Description of the Related Art In recent years, one-piece metal halide lamps, which are one type of one-piece discharge lamps, have high efficiency and high color rendering characteristics. Widely used. An example of a conventional example of such a one-piece metal halide lamp will be described with reference to FIG.

[0003] This one-base metal halide lamp includes an arc tube 1 formed of quartz glass and a base 2 for holding the arc tube 1. The arc tube 1 has a discharge vessel part 3 formed in a hollow elliptical sphere shape, and a pair of sealing parts 4a, 4b formed at both ends of the discharge vessel part 3.

In the discharge vessel 3, xenon (Xe), krypton (Kr), argon (A)
r), a starting gas selected from scandium (Sc), sodium (Na), lithium (Li), and other rare earths; cadmium (C)
d), magnesium (Mg), cobalt (Co), chromium (Cr), zinc (Zn), nickel (Ni), manganese (Mn), aluminum (Al), antimony (S
b), beryllium (Be), rhenium (Re), gallium (Ga), and a second group of metal halides selected from mercury (Hg) are enclosed. Further, the distal ends of the pair of electrodes 5a and 5b are opposed to each other at both ends of the discharge vessel portion 3.

The sealing portions 4a and 4b have rear ends of the electrodes 5a and 5b, metal foils 6a and 6b spot-welded to the rear ends of the electrodes 5a and 5b, and one end spots on the metal foils 6a and 6b. The welded external power supplies 7a and 7b are sealed. The other ends of the external power supplies 7a and 7b are drawn out of the sealing portions 4a and 4b, respectively.

[0006] One external power supply 7a includes a sealing portion 4a.
After being pulled out of the sealing portion 4a,
4b and along the side of the discharge vessel part 3.
The external power supply 7a and the other external power supply 7b extend in the same direction and are held by the base 2. In addition,
The sealing portion 4b is also held by the base 2 together with the external power supply 7b.

[0007]

When the one-piece metal halide lamp having such a structure is used as a headlight of an automobile or the like, vibration occurs during traveling to cause the light emitting tube 1 and the sealing portion 4a in the external power supply 7a to move. Vibration different from that of the part being pulled out may occur, and the junction between the external power supply 7a and the metal foil 6a may be peeled off, resulting in a failure in energization.

Japanese Utility Model Application Laid-Open Publication No. 48-69587 discloses an invention in which an arc tube and an external power supply are fixed by a band so that the arc tube and the external power supply do not generate different vibrations. I have. However, in the present invention, the heat of the arc tube is easily radiated through the band and the external power supply, and the discharge is hardly stabilized. Therefore, an outer tube that surrounds the entire arc tube and the external power supply is required, and it is difficult to reduce the size.

Therefore, the present invention provides a structure in which an arc tube and an external power supply arranged along the side of the arc tube vibrate integrally, and the arc tube and the external power supply generate different vibrations. Provided is a single-ended discharge lamp capable of preventing peeling of a generated joint between an external power supply and a metal foil and maintaining the temperature of an arc tube, a shield beam device and a shield beam lighting device using the same. The purpose is to:

[0010]

According to a first aspect of the present invention, there is provided a single-cap discharge lamp having a discharge vessel in which a discharge medium is sealed and a pair of electrodes arranged opposite to each other, and formed at both ends of the discharge vessel. And a sealing portion in which a metal foil connected to the electrode is sealed, and the other end of the external power supply body having one end connected to the metal foil is drawn out of the sealing portion. When;
An outer tube surrounding the outer periphery of the arc tube and fixed to the arc tube; one external power supply and another external power supply arranged along the outer peripheral surface of the outer tube being the same And a coupling means for coupling the external power supply body disposed along the outer peripheral surface of the outer tube to the outer peripheral surface of the outer tube.

The outer tube is made of quartz glass or ceramics, and stabilizes the discharge in the discharge vessel by keeping the arc tube warm.

The connecting means includes various mechanical means in addition to bonding and welding.

Therefore, in this single-ended discharge lamp, the outer tube is fixed to the arc tube, and an external power supply disposed along the outer peripheral surface of the outer tube is coupled to the outer peripheral surface of the outer tube by coupling means. Therefore, when vibration from the outside is transmitted to the single-cap discharge lamp, the arc tube, the outer tube, and the external power supply vibrate integrally. For this reason, peeling of the joint between the external power supply and the metal foil, which is caused by the occurrence of different vibrations between the arc tube and the external power supply, is prevented. Also, collision between the outer tube and the external power supply caused by different vibrations of the outer tube and the external power supply, and damage to the outer tube due to the collision are prevented.

Further, since the arc tube is surrounded by the outer tube and the outer tube and the external power supply are coupled by the coupling means, heat radiation from the arc tube through the coupling means and the external power supply is provided. Is prevented.

According to a second aspect of the present invention, in the one-sided discharge lamp according to the first aspect of the present invention, the coupling means is provided on an outer periphery of the external power supply provided along an outer peripheral surface of the outer tube. It comprises a fixed sleeve, and an adhesive bonding the outer peripheral surface of the sleeve and the outer peripheral surface of the outer tube.

The sleeve is made of quartz glass or ceramics. When the sleeve is installed around the external power supply, the potential difference between the external power supply and the inside of the discharge container causes the discharge medium sealed in the discharge container to be sucked toward the external power supply and the minute amount of the discharge container is reduced. It is possible to prevent the discharge vessel from slipping out of the gap.

Since the temperature rise of the outer tube when the arc tube is turned on is lower than that of the arc tube, an adhesive having low heat resistance can be used as an adhesive for adhering the outer tube and the sleeve.

Therefore, by bonding the outer peripheral surface of the sleeve and the outer peripheral surface of the outer tube, when the vibration from the outside is transmitted to the one-sided discharge lamp, the arc tube, the outer tube, the sleeve and the sleeve are fixed. The external power supply vibrates together,
Peeling of the joint between the external power supply and the metal foil and collision of the outer tube and the sleeve to prevent damage to the outer tube and the sleeve are prevented.

According to a third aspect of the present invention, in the single-ended discharge lamp according to the first aspect of the present invention, the coupling means includes the external power supply body and the external power supply disposed along an outer peripheral surface of the outer tube. It is a band wound so as to fix the tube.

The band is preferably made of a metal that does not loosen the fixed state of the outer tube and the external power supply even when external vibration is transmitted. It is preferable that the band is mounted near a location where the amplitude becomes largest when vibration from the outside is transmitted, for example, near an end of the outer tube opposite to the side where the base is provided.

Therefore, the outer tube and the external power supply are fixed by winding the band, and when vibration from the outside is transmitted, the light emitting tube, the outer tube and the external power supply vibrate integrally, and It is possible to prevent the joint between the power supply and the metal foil from being peeled off or the outer tube from being hit by the outer tube and the outer power supply from being damaged.

According to a fourth aspect of the present invention, there is provided a shielded lamp device according to any one of the first to third aspects, and a one-sided discharge lamp which holds the base side of the one-sided discharge lamp. And a light-transmitting cover that is disposed in front of the direction of travel of the light reflected by the reflector and fixed to the reflector.

Therefore, in this shield beam device, when an external vibration is transmitted, the joint between the external power supply and the metal foil is peeled off, or the outer tube hits the external power supply or the sleeve and is damaged. And the durability is improved.

According to a fifth aspect of the present invention, there is provided a shielded beam lighting device comprising: the shielded beam device according to the fourth aspect; and a lighting circuit for controlling lighting of the discharge lamp.

Therefore, in this shield beam lighting device, when vibration from the outside is transmitted, the joint between the external power supply and the metal foil is peeled off or the outer tube hits the external power supply or the sleeve. Damage is prevented and durability is improved.

[0026]

FIG. 1 shows a first embodiment of the present invention.
A description will be given based on FIG. Note that the same portions as those described in FIG. 5 are denoted by the same reference numerals, and description thereof is omitted (the same applies hereinafter). FIG. 1 is a front view showing a one-piece metal halide lamp which is one of the one-piece discharge lamps, and FIG.
FIG. 2 is a perspective view showing a shield beam device and a shield beam lighting device using the one-base discharge lamp shown in FIG.

First, a one-piece metal halide lamp will be described. This one-piece metal halide lamp is shown in FIG.
As with the single-ended metal halide lamp shown in FIG. 1, the light emitting tube 1 includes a discharge vessel portion 3 and a pair of sealing portions 4a and 4b. The discharge vessel part 3 has an inner diameter of 4 in the short diameter direction.
mm, and a discharge medium similar to that described in the conventional example shown in FIG. 5 is sealed therein. Distal end portions of the pair of electrodes 5a and 5b are arranged opposite to each other at both ends of the discharge vessel portion 3.

The electrodes 5a, 5b are provided in the sealing portions 4a, 4b.
, The metal foils 6a, 6b spot-welded to the rear ends of the electrodes 5a, 5b, and the external power supply bodies 7a, 7b, one end of which is spot-welded to the metal foils 6a, 6b, are sealed. I have. The electrodes 5a and 5b are made of thorium-containing tungsten and have a shaft diameter of 0.4 mm and a length of 6 mm. The metal foils 6a and 6b are made of molybdenum and have a width of 1.5 mm, a length of 15 mm, and a thickness of 22 μm.
m. One external power supply 7a is formed by connecting a molybdenum wire having a shaft diameter of 0.5 mm and a length of 25 mm to a nickel wire having a shaft diameter of 0.5 mm and a length of 50 mm. I have. The side connected to the metal foil 6a is a molybdenum wire. The other external power supply 7b has a shaft diameter of 0.5 mm and a length of 25 mm.
Of molybdenum.

A cylindrical outer tube 8 surrounding the arc tube 1 is provided on the outer periphery of the arc tube 1. The outer tube 8 is welded to the outer periphery of the sealing portions 4a and 4b at both ends. I have. Outer tube 8
Is made of quartz glass and has an inner diameter of 9 mm and a length of 4
It is formed at 0 mm.

A cylindrical sleeve 9 extending along the longitudinal direction of the outer tube 8 is bonded to the outer peripheral surface of the outer tube 8 with an adhesive. The sleeve 9 is made of quartz glass and has an inner diameter of 2 mm. The outer tube 8 and the sleeve 9 are bonded to each other at least at two positions on both ends of the outer tube 8.

One external power supply 7a is connected to the sealing portion 4a.
After being pulled out of the sleeve 9, it is bent into a U-shape and inserted into the sleeve 9. Thereby, the external power supply 7a is connected to the outer peripheral surface of the outer tube 8, and the sleeve 9 and the adhesive are
Forming means 10 for connecting the external power supply 7a to the outer tube 8 is formed.

The end of the sleeve 9 into which the one external power supply 7a is inserted and the end of the sealing portion 4b in which the other external power supply 7b is sealed are inserted into the base 11, and a ceramic It is fixed with an inorganic adhesive. The base 11 is made of epoxy resin and has a hole diameter of 18 mm and a depth of 15 mm.
mm.

Here, the assembling process of the one-piece metal halide lamp will be described. First, a quartz glass pipe in which the sealing portions 4a and 4b are not completely sealed and a hole communicating with the space in the discharge vessel portion 3 is opened in the sealing portions 4a and 4b is prepared. Electrode 5a, metal foil 6a and external power supply 7
a, which is integrated by spot welding, is inserted from the sealing portion 4a side, the tip of the electrode 5a is positioned in the discharge vessel portion 3, and the sealing portion 4a is heated and melted using an oxyhydrogen burner. And pinch hermetically.

Next, in an atmosphere of an inert gas such as nitrogen gas, a mixture ratio of 1: 5 selected from the first group of metal halide compounds described in the prior art is introduced into the discharge vessel section 3 from the sealing section 4b side. 0.6mg of ScI ₃ -NaI,
ZnI ₂ selected from the second group of metal halides
0 mg is enclosed. After that, the electrode 5b, the metal foil 6b, and the external power supply 7b, which are integrated by spot welding, are inserted from the side of the sealing portion 4b, and the distance between the electrodes 5a and 5b is 4.
Position it so that it becomes 2 mm.

Then, using a normal vacuum device, 400 xtorr of xenon gas is introduced into the discharge vessel part 3 so that the internal pressure after completion is 5 atm, and then the end of the sealing part 4a of the discharge vessel part 3 is introduced. While cooling with liquid nitrogen, the sealing portion 4b is heated and melted using an oxyhydrogen burner to pinch it in an airtight state.

Next, the sleeve 9 is bonded to the outer peripheral surface of the outer tube 8 with an adhesive. The welding may be performed using an oxyhydrogen burner without using an adhesive.

Next, after one external power supply 7a is bent in a U-shape, the outer tube 8 is placed on the outer periphery of the arc tube 1 and the external power supply 7a bent in a U-shape is connected to the distal end thereof. Through the sleeve 9.

Next, both ends of the outer tube 8 are welded to the sealing portions 4a and 4b, respectively, using an oxyhydrogen burner.

Next, the end of the sealing portion 4b in which the external power supply 7b is sealed and the end of the sleeve 9 into which the external power supply 7a is inserted are positioned in the base 11, and By filling the ceramics 11 with the inorganic adhesive of ceramics, the assembly of the one-sided metal halide lamp is completed.

Next, a shield beam device and a shield beam lighting device using the one-piece metal halide lamp having the above-described structure will be described.

As shown in FIG. 2, the shield beam device includes a one-piece metal halide lamp having the above-described structure, a reflecting plate 12, and a light-transmitting cover 13. The reflecting plate 12 holds the base 11 side of the one-base metal halide lamp, is formed in a concave shape that reflects light emitted from the one-base metal halide lamp in a predetermined direction, and has an opening at the front side in the traveling direction of the reflected light. ing.
The translucent cover 13 is fixed to an opening surface of the reflection plate 12.

The shield beam lighting device comprises the above-described shield beam device and a lighting circuit 15 connected to the lead wire 14 drawn out of the base 11 and controlling the lighting of a single-base metal halide lamp.

In such a configuration, according to the single-base discharge lamp, the outer tube 8 is welded to the arc tube 1 and the outer tube 8 is welded.
Since the external power supply 7a is inserted through the sleeve 9 when the external vibration is transmitted to the one-piece metal halide lamp, the arc tube 1, the outer tube 8, the sleeve 9, and the external power The supply body 7a vibrates integrally. Therefore, the luminous tube 1 and the external power supply 7a do not generate different vibrations, and the luminous tube 1 and the external power supply 7a generate different vibrations. Separation of the bonding portion can be prevented, and an energization failure due to the occurrence of such separation can be prevented.

When an external vibration is transmitted,
The external power supply 7a and the sleeve 9 do not hit the outer tube 8, and it is possible to prevent the outer tube 8 and the sleeve 9 from being damaged by such collision.

Since the external power supply 7a is connected to the outer tube 8 surrounding the outer periphery of the arc tube 1, the heat generated in the discharge vessel 3 is hard to be radiated from this connection portion. Discharge can be stabilized.

Here, the inventor of the present invention has a single-ended metal halide lamp having the above-described structure and a rated output of 35.
A prototype of 30 W-types was tested, and 15 of them were actually mounted on a headlight of a car and tested on a general road all day and night. With respect to the remaining fifteen pieces, a test in which the light source was turned on for one hour and turned off for ten minutes while applying vibration equivalent to the vibration in the automobile running in a horizontal direction was performed.
Time went.

After the end of each test, for each one-sided metal halide lamp, the presence or absence of peeling of the joint between the external power supply 7a and the metal foil 6a, damage to the outer tube 8, and damage to the sleeve 9 were visually observed. . As a result, no peeling or breakage occurred.

Next, a second embodiment of the present invention will be described with reference to FIG.
It will be described based on. The one-piece metal halide lamp according to the present embodiment has the same basic structure as the one-piece metal halide lamp shown in FIG. 1, and external power supply 7 a provided along the outer peripheral surface of outer tube 8 is removed. The structure of the coupling means for coupling to the tube 8 is different. In the present embodiment, a band 16 wound so as to fix the outer tube 8 and the sleeve 9 is used as the coupling means. The band 16 is formed of a nickel plate having a width of 2 mm and a thickness of 0.3 mm. The band 16 is attached to an end of the outer tube 8 on a side away from the base 11.

In such a configuration, the band 16 is wound around the outer tube 8 and the sleeve 9 so as to fix the outer tube 8 and the sleeve 9, so that when an external vibration is transmitted to the one-piece metal halide lamp, the arc tube 1 and the outer tube The sleeve 8, the sleeve 9, and the external power supply 7a vibrate integrally. For this reason, as in the case described in the first embodiment, the joint between the external power supply 7a and the metal foil 6a is peeled off,
The outer tube 8 and the sleeve 9 are prevented from being damaged due to the collision between the outer tube 8 and the sleeve 9.

A prototype was also manufactured for the single-ended metal halide lamp of the present embodiment, and the same test as the test described in the first embodiment was performed. According to the test results, in any one-piece metal halide lamp,
Peeling of the joint between the external power supply 7a and the metal foil 6a,
The outer tube 8 and the sleeve 9 were not damaged.

Next, a third embodiment of the present invention will be described with reference to FIG.
It will be described based on. The one-piece metal halide lamp of the present embodiment has the same basic structure as that of the one-piece metal halide lamp shown in FIG. 1 or 3, and an external power supply provided along the outer peripheral surface of the outer tube 8. The structure of the connecting means for connecting 7a to the outer tube 8 is different. In the present embodiment, three projections 17a, 17b, 1 formed on the outer peripheral surface of the outer tube 8 are provided.
7c and a pair of bent projections 18a and 18b formed on the external power supply 7a constitute a coupling means 19.

The three projections 17a, 17b, 17c are connected to the external power supply 7a, which is in contact with the outer peripheral surface of the outer tube 8 by the upper and lower two projections 17a, 17b and the central projection 17b.
It is arranged so that it can be inserted. Bending projection 18a,
18b, when the external power supply 7a is brought into contact with the outer peripheral surface of the outer tube 8 and is sandwiched between the projections 17a, 17b, 17c,
The outer tube 8 is formed so as to be hooked on a step formed at both ends.

In such a configuration, the external power supply 7a provided along the outer peripheral surface of the outer tube 8 is
17b, 17c and bent projections 18a, 1
The external power supply 7a can be fixed to the outer peripheral surface of the outer tube 8 by mechanical means by hooking the outer tube 8b on the steps at both ends of the outer tube 8.

With such mechanical means, the external power supply 7
When vibration from the outside is transmitted to the one-piece metal halide lamp in which a is connected to the outer tube 8, the light emitting tube 1, the outer tube 8 and the external power supply 7a vibrate integrally. Therefore, the first
In the same manner as described in the second embodiment or the second embodiment, the external power supply 7a and the metal foil 6a
Of the outer tube 8 due to the peeling of the joint between the outer tube 8 and the outer tube 8 and the external power supply 7a.

[0055]

According to the single lamp discharge lamp of the first aspect of the present invention, the outer tube is fixed to the arc tube, and the external power supply body disposed along the outer peripheral surface of the outer tube is connected to the outer tube. Since the outer peripheral surface is coupled to the outer peripheral surface by the coupling means, when an external vibration is transmitted to the single-cap discharge lamp, the arc tube, the outer tube, and the external power supply vibrate integrally. For this reason, it is possible to prevent the joint between the external power supply and the metal foil in the arc tube, which is caused by the occurrence of different vibrations between the arc tube and the external power supply. The durability against vibration can be improved. Furthermore, it is possible to prevent collision between the outer tube and the external power supply caused by different vibrations of the outer tube and the external power supply, and damage to the outer tube due to the collision. Furthermore, since the arc tube is surrounded by an outer tube and an external power supply is coupled to the outer tube by a coupling means, heat radiation from the arc tube through the coupling means and the external power supply can be prevented, and discharge can be prevented. The discharge in the container can be stabilized.

According to the second aspect of the present invention, in the single-ended discharge lamp according to the first aspect of the present invention, the sleeve fixed to the outer periphery of the external power supply provided along the outer peripheral surface of the outer tube. Since a connecting means comprising an adhesive bonding the outer peripheral surface of the sleeve and the outer peripheral surface of the outer tube is provided, when external vibration is transmitted to the single-cap discharge lamp, the arc tube, the outer tube and the sleeve are provided. And the external power supply fixed to the sleeve vibrates integrally to prevent peeling of the joint between the external power supply and the metal foil and damage to the outer tube and the sleeve caused by the collision between the outer tube and the sleeve. be able to.

According to a third aspect of the present invention, in the one-sided discharge lamp according to the first aspect of the present invention, the external power supply and the outer tube are disposed along the outer peripheral surface of the outer tube as the coupling means. When the external vibration is transmitted to the one-sided discharge lamp, the arc tube, the outer tube and the external power supply vibrate integrally, and the external power supply Peeling of the joint between the body and the metal foil and breakage of the outer tube caused by the external power supply colliding with the outer tube can be prevented.

According to the shielded beam apparatus of the present invention, when the vibration is transmitted from the outside by using the one-sided discharge lamp according to any one of the first to third aspects, the one-sided discharge lamp is used. It is possible to prevent the joint between the external power supply and the metal foil from being peeled off, or to prevent the outer tube from hitting the external power supply or the sleeve and being damaged, thereby improving the durability.

According to the shielded-beam lighting device of the fifth aspect of the present invention, since the shielded-beam device of the fourth aspect is used, when the vibration is transmitted from the outside, the external power supply of the single-ended discharge lamp can be used. It is possible to prevent the joint portion with the metal foil from being peeled off, or to prevent the outer tube from being damaged by colliding with the external power supply or the sleeve, thereby improving the durability.

[Brief description of the drawings]

FIG. 1 is a front view showing a one-piece metal halide lamp according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a shield beam device and a shield beam lighting device using the one-base metal halide lamp.

FIG. 3 is a front view showing a one-piece metal halide lamp according to a second embodiment of the present invention.

FIGS. 4A and 4B show a part of a one-piece metal halide lamp according to a third embodiment of the present invention, wherein FIG.
(B) is a side view.

FIG. 5 is a front view showing a conventional one-piece metal halide lamp.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Arc tube 3 Discharge container part 4a, 4b Sealing part 5a, 5b Electrode 6a, 6b Metal foil 7a, 7b External power supply 8 Outer tube 9 Sleeve 10, 16, 19 Coupling means 11 Base 12 Reflector 13 Translucency Cover 15 Lighting circuit

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Mikio Matsuda 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Toshiba Lighting & Technology Corporation F-term (reference) 5C043 AA10 AA14 AA17 CC03 CD05 DD02 DD03 DD17 DD18 DD19 DD20 DD22 DD24 EA01

Claims (5)

[Claims] 1. A discharge vessel section in which a discharge medium is sealed and a pair of electrodes are arranged to face each other, and a sealing section formed at both ends of the discharge vessel section and sealed with a metal foil connected to the electrodes. A light-emitting tube having one end connected to the metal foil and the other end of the external power supply body drawn out of the sealing portion; and fixed to the light-emitting tube around the outer periphery of the light-emitting tube. Outer tube;
A base for holding one of the external power supply units and the other of the external power supply units disposed along the outer peripheral surface of the outer tube at positions extending in the same direction; Coupling means for coupling the external power supply disposed along the outer peripheral surface of the outer tube. 2. The coupling means comprises: a sleeve fixed to an outer periphery of the external power supply disposed along an outer peripheral surface of the outer tube; and an outer peripheral surface of the sleeve and an outer peripheral surface of the outer tube. 2. The discharge lamp according to claim 1, wherein the discharge lamp comprises an adhesive. 3. The one-sided mouth according to claim 1, wherein the coupling means is a band wound so as to fix the external power supply body and the outer tube disposed along an outer peripheral surface of the outer tube. Gold discharge lamp. 4. A one-sided discharge lamp according to claim 1, wherein said one-sided discharge lamp is held on said base side and light emitted from said one-sided discharge lamp is reflected in a predetermined direction. A shield beam device, comprising: a reflecting plate to be illuminated; and a translucent cover disposed forward of the light reflected by the reflecting plate and fixed to the reflecting plate. 5. A shield beam device according to claim 4,
A lighting circuit for controlling lighting of the discharge lamp;