JPH05325899A - Tubular bulb - Google Patents

Abstract

PURPOSE:To provide a tubular bulb which does not generate a leakage, a foil removal, a center slippage of discharge electrode or filament, a reduction of a good appearance, and the like, in a tubular bulb using a leading-in body in which a separator glass is placed between plural sheets of metal foils. CONSTITUTION:While plural sheets of metal foils 4A and 4B are connected to an inner conductor 2, a leading-in body 1 composed by placing a separator glass 5 which has a recess 51 to house the end of the above conductor 2, between the metal foils 4A and 4B, is sealed at the end of a quartz glass bulb 6 to form this tubular bulb.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high pressure discharge lamp or a halogen bulb, and more particularly to a structure of an introduction body of a sealing portion thereof.

[0002]

2. Description of the Related Art Short arc metal halide lamps,
High-pressure discharge lamps such as ultra-high-pressure mercury lamps and xenon lamps, or halogen bulbs that use quartz glass as a bulb are used in various applications as a compact light source consisting of an arc tube without an outer tube. ..

In order to maintain the airtightness of these tubes with quartz glass, a metal foil made of molybdenum foil or the like is used as an introduction body in the sealing portion. Usually, this molybdenum foil has a thickness of 20 to 30 μm. If it is thicker than this, the quartz glass bulb may crack due to the thermal expansion coefficient or the airtightness may not be maintained. Not only foil breakage occurs during sealing work and lighting, but also the current is limited.

Therefore, with this kind of lamp, 10 ampere, 2
Lamps of 0 ampere and large current type use multiple sheets of this metal foil. As shown in FIG. 3, the introduction body 1 using a plurality of metal foils, for example, two metal foils, includes an internal conductor 2
Also, molybdenum foils 4A and 4B are welded to the flat portions 21 and 31 formed by cutting the upper and lower surfaces of the outer conductor 3, respectively. A separator glass 5 made of rectangular flat quartz glass is interposed between them as shown by an arrow.

The introduction body 1 having such a structure is arranged at the open end of the quartz glass bulb 6 shown in FIG. 2, and if the end of the bulb 6 is heated and melted to form the sealing portion 61, The molybdenum foils 4A and 4B are hermetically sealed in the sealing portion 61.

However, when the conductors 2 and 3 are welded to the molybdenum foils 4A and 4B, the introduction body 1 having such a structure is
Molybdenum foil 4A, which has no conductors 2 and 3 below,
The welding electrode may inadvertently press the corner portion 41 of 4B due to lateral displacement or the like, and the corner portion 41 of the extremely thin molybdenum foils 4A and 4B may be bent downward. Further, the corner portions 41 of the molybdenum foils 4A and 4B are subjected to the same pressing action as above by the glass of the valve 6 which is melted and contracted during the sealing work, and the separator glass 5 is locked. Since there is no means, the separator glass 5 may be displaced and protrude from the side edges of the molybdenum foils 4A and 4B.

[0007]

When the corners of the metal foil are bent downward as described above, the fused silica glass may not enter the bent inner side, which may cause a cavity to cause a leak. is there. Also, when pressed by molten glass, tension is applied to the metal foil to cut this foil, and when tension remains locally, the foil is cut during lighting due to heat expansion and contraction due to lighting and extinguishing of the lamp. I have something to do. Furthermore, if the separator glass is displaced from the center axis, the discharge electrodes and filaments connected to the inner conductor will bend from the center axis of the bulb, and the light center will shift when the bulb is attached to a device and turned on. There are problems such as not being able to obtain a light distribution, and having an uneven thickness part in the sealing part, resulting in a poor appearance.

The present invention has been made in view of the above circumstances, and in a tube using an introduction body in which a separator glass is interposed between a plurality of metal foils, leakage, foil breakage, discharge electrode or filament center deviation, It is an object of the present invention to provide a tube having no risk of appearance deterioration.

[0009]

A tube according to claim 1 of the present invention has a recess for connecting a plurality of metal foils to an inner conductor and accommodating an end portion of the conductor between the metal foils. It is characterized in that the introduction body with the separator glass interposed is sealed at the end of the quartz glass bulb.

The tube according to claim 2 of the present invention is characterized in that the metal foil does not protrude from the edge of the separator glass.

[0011]

[Function] Since the inner glass or the outer metal is formed in the end portion of the separator glass to accommodate the inner conductor and the outer conductor, the center axes of the conductor and the metal foil are accurately aligned when welding the inner conductor and the outer conductor to the metal foil. It can be matched and the work becomes easier. In addition, since the metal foil does not protrude from the edge of the separator glass, the molten glass does not strongly press the corner portion of the metal foil when sealing the introduction body in the valve,
Since undesired stress is not applied to the metal foil, it is possible to prevent the metal foil from being cut, and it is possible to prevent the occurrence of a leak without forming a gap between the metal foil and the glass.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an introduction body 1 according to the present invention, and FIG. 2 shows a short arc metal halide lamp. The same parts as those in FIG. 3 described above are designated by the same reference numerals and the description thereof will be omitted.

Recesses 51 and 52 for accommodating the ends of the electrode rod 2 and the outer conductor 3 which are inner conductors are formed at the centers of both ends of the separator glass 5 in the longitudinal direction. This separator glass 5 is made up of metal foils 4A and 4B that are stacked one above the other.
The metal foils 4A and 4B do not protrude from the edge of the separator glass 5 by the same size or larger. In addition, 53, ...
Is a convex portion formed on the side of the concave portions 51 and 52, and 22 is a coil wound around the internal conductor 2.

In order to assemble such an introduction body 1, metal foil such as molybdenum foil 4A is formed on and under the separator glass 5.
4B are stacked and housed in one of the recesses 51 until the tip of the electrode rod 2 hits the inner bottom of the recess 51, and the welding electrodes are formed on the upper and lower molybdenum foils 4A and 4B where the flat portion 21 of the electrode rod 2 exists. Weld the three by applying a current. Next, the flat portion 31 of the outer conductor 3 is inserted and housed in the other recess 52, and welding electrodes are applied to the upper and lower molybdenum foils 4A and 4B where the flat portion 31 of the outer conductor 3 is present in the same manner as above. Then, the three are welded together.

The introduction body 1 is sealed in the same manner as before at both ends of a substantially oval valve 6 made of quartz glass, and the inside of the valve 6 is exhausted from an exhaust pipe (not shown).
3, HoBr3, TmBr3, CsI, ScI3, Na
After filling a halogen compound such as I, an inert gas such as mercury and argon, the exhaust pipe is sealed to complete the lamp.

In the introducer 1 thus constructed, the ends of the electrode rod 2 and the outer conductor 3 are housed in the recesses 51 and 52 of the separator glass 5, so that the introduction can be prevented. In addition, even when the welding electrode is slightly displaced from the center of the electrode rod 2 and the outer conductor 3 and the corner portion 41 of the molybdenum foil 4A, 4B is pressed when handling the introduction body 1 or during welding work, the electrode rod 2, Since the convex portions 53 of the separator glass 5 are present on the left and right portions of the end portion of the outer conductor 3, the corner portion 41 is not bent inward.

Next, a specific example will be described.

Concrete Example 1 Lamp rating 2 Kw (lamp voltage 120 V, lamp current 20 A) Elliptical bulb Minor diameter part inner diameter 36 mm, long diameter part inner diameter 50 mm Discharge electrode distance 30 mm Lamp (sealing part end) total length 140 mm Encapsulation DyBr3 3 mg, HoBr3 3 mg, TmBr3 3 mg, CsI 10 mg, Hg 90 mg, Ar 100 torr, metal foil (molybdenum foil) thickness 26 μm, width 6 mm, length 125 mm, inner conductor (electrode rod) outer diameter 2 mm, length 25 mm, flat Part thickness 1 mm, length 5 mm, separator glass (present invention) thickness 1 mm, width 6 mm, length 125 mm, recess width 2.1 mm, length 4 mm, (conventional) thickness 1 mm, width 6 mm, length 115 mm, No recesses Only the product of the present invention and the separator glass part differ from the product of the present invention We made 20 pieces each of the product and a blinking test (lighting 5.5 hours, extinguishing 0.5 hours) for 3000 hours. With the conventional product, 7 lamps were provided with molybdenum foil near the electrode rod welding part. Although the lamp melted, the lamp of the present invention had no melted molybdenum foil.

Concrete Example 2 Lamp rating 1 Kw (lamp voltage 120 V, lamp current 10 A) Elliptical bulb Minor diameter part inner diameter 25 mm, Major diameter part inner diameter 40 mm, Discharge electrode distance 20 mm Lamp (sealing part end) total length 100 mm Encapsulation ScI3 3mg, NaI 15mg, Hg 70mg, Ar 100 torr, metal foil (molybdenum foil) thickness 26μm, width 5mm, length 100mm, inner conductor (electrode rod) outer diameter 1.5mm, length 20mm, flat part thickness 1 mm, length 4 mm, separator glass (invention) thickness 1 mm, width 5 mm, length 100 mm, recess width 1.55 mm, length 3 mm, (conventional) thickness 1 mm, width 5 mm, length 92 mm, recessless book Each of the invention product and the conventional product, which differs from the invention product only in the separator glass portion, are manufactured in 20 pieces. When a time flashing test (lighting 5.5 hours, extinguishing 0.5 hours) was performed, the molybdenum foil in the vicinity of the electrode rod welded part melted down to 5 lamps in the conventional product, but the molybdenum foil in the present invention product No lamp was blown.

The present invention is not limited to the above embodiment. For example, the bulb is not limited to a metal halide lamp, but may be an ultra-high pressure mercury lamp, a xenon lamp, a halogen bulb, or the like, and the bulb shape is not limited to the substantially elliptical shape shown.
The lamp may have a spherical shape, a straight tube shape, a curved tube shape or the like, and needless to say, it is not limited to the both-ends-sealed type, but one having a plurality of sets of introduction bodies sealed at one end is also applicable.

Further, in the above embodiment, the concave portions are formed at both ends of the separator glass, but the concave portions may be at least only on the side of the internal conductor connected to the metal foil. This is indispensable because the inner conductor side is close to the discharge electrode and the filament so that the temperature rises and the thermal influence is large.

In the above embodiment, the case where two metal foils are used has been described, but it goes without saying that the present invention can be applied to the case where three or more metal foils are used depending on the current capacity and shape. In addition, one metal foil is not limited to one electrode rod and one external conductor connected, but a plurality of conductors may be connected to one metal foil depending on the current capacity.
In this case, a separator glass having a plurality of recesses may be used. Further, the outer conductor is not limited to the above-mentioned one, and may be a metal foil for glass sealing extended to the outside of the sealing portion of the bulb.

Further, in the above embodiment, the electrode shaft is sandwiched between two metal foils from above and below and welded at once, but the welding of these three members is not limited to one, and, for example, the electrode rod and the metal foil on the upper side. After welding and, place separator glass 5 and
It does not matter if the lower metal foil is welded.

[0024]

As described in detail above, according to the present invention, since the separator glass is laminated so as to cover the entire surface of the thin metal foil, an undesired stress is applied to the metal foil during welding of the metal foil and the conductor. It is possible to prevent the metal foil from being blown out in the flashing cycle of the lamp. Also, since the inner conductor such as the electrode rod can be guided and welded into the recess of the separator glass, the discharge electrode and the filament can be easily aligned with the central axis of the lamp, and the light distribution characteristic is deteriorated due to the deviation of the light center of the lamp. Can be achieved. Further, when the concave portion is formed on the outer conductor side as well, the outer conductor can be accurately connected to the base terminal so that the base is not bent, so that the deterioration of the light distribution characteristic due to the light center deviation can be prevented as in the above. .. Furthermore, since the glass wall cannot be locally accumulated in the sealing portion, the appearance of the lamp can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an introduction body of the present invention.

FIG. 2 is a partial sectional front view showing a short arc metal halide lamp.

FIG. 3 is a perspective view showing an example of a conventional introducing member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Introduction body 2 Internal conductor (electrode rod) 21, 31 Flat part 3 External conductor 4A, 4B Metal foil (molybdenum foil) 5 Separator glass 51, 52 Recessed part 53 Convex part 6 Quartz glass valve 61 Sealed part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideki Ito 1-4-2 Mita, Minato-ku, Tokyo Toshiba Lighting & Technology Corporation

Claims (2)

[Claims] 1. A quartz glass bulb end portion is provided with an introduction body formed by connecting a plurality of metal foils to an inner conductor and interposing a separator glass having a concave portion accommodating an end portion of the conductor between the metal foils. A tube characterized by being sealed in. 2. The tube according to claim 1, wherein the metal foil does not protrude from the edge of the separator glass.