JPH0877975A - Discharge lamp - Google Patents

Abstract

PURPOSE: To provide a discharge lamp having an airtight sealing structure, which is especially suitable for heavy-current, by combining a glass sealing body, a glass member, a metallic plate, an internal lead bar, an electrode, a glass cylinder, an external lead bar, and metallic foil so as to perform the specific action. CONSTITUTION: A column glass member l is provided with a tapered outer circumferential face, which tapers off to a point, on a circumferential wall 16 in the part continuing to one end face 11 on a light emission space surrounding part 82 side, and the part on one end face 11 side is formed into a truncated cone. In the other side face 12 on the outer end side of a sealing tube part 81, a hole 13 for arranging an external lead bar 5 is formed. On one end face 11 of the glass member 1, a disk metallic plate 3 provided with a diameter slightly smaller than that of the one end face 11 is arranged, while in the center of the metallic plate 3, an internal lead bar 4 is fixed extendingly in the axis direction of a sealing body 8 toward the light emission space surrounding part 82, and at the tip of the bar 4, an electrode 9 is arranged. In this discharge lamp, no metallic tube is cut in a sealing process of the sealing tube part 81 even though it is for heavy-current, and no accident occurs in a glass part in the sealing tube part 81, so that the discharge lamp provided with a long using life can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp, and more particularly to a discharge lamp having a hermetically sealed structure suitable for large currents.

[0002]

2. Description of the Related Art Discharge lamps, such as mercury lamps, are widely used in the fields of utilizing ultraviolet rays emitted from the lamps, such as the photochemical industry, the semiconductor device manufacturing field, and other fields.

For example, in a high-pressure or ultra-high-pressure mercury lamp for a large current, the amount of mercury, which is the main component of the luminous gas, is large, the gas pressure in the arc tube during lighting is very high, and the calorific value is large. The glass of the hermetically sealed portion is required to have high heat resistance and pressure resistance. Further, it is necessary that mercury in the arc tube is completely evaporated during lighting, and therefore, it is necessary that there is no low temperature portion where condensation of mercury occurs in the arc tube during lighting.

Therefore, in the conventional high-pressure or ultra-high-pressure mercury lamp, the so-called rod seal for achieving the hermetic sealing of the arc tube by directly welding the glass forming the arc tube to the lead rod for power supply. Instead of the structure, a so-called foil seal structure using a metal foil for sealing is adopted.

FIG. 4 is an explanatory view showing an example of a high pressure mercury lamp having a foil seal structure. In this high-pressure mercury lamp, the peripheral wall 16 of the bottomed cylindrical glass member 1 having a tapered outer peripheral surface on the peripheral wall portion continuing to the one end surface 11 on the bottom wall B side is separated from each other in the peripheral direction of the glass member 1. Then, the strip-shaped metal foil 2 is stretched in the axial direction of the glass member 1, for example, 4
It is arranged. One end 2 of each of these metal foils 2
1 is connected to a metal plate 3 arranged at a base end portion of an internal lead bar 4 arranged so as to extend from one end surface 11 of the glass member 1, while the other end portion 22 of each metal foil 2 is connected.
Are connected to the outer circumference of the external lead rod 5 inserted into the cylindrical hole of the glass member 1. An inner lead rod holding cylinder 6 made of glass is arranged on the outer periphery of the inner lead rod 4, and a glass member 6 is provided between the outer periphery of the outer lead rod 5 and the inner periphery of the cylindrical hole of the glass member 1. The outer lead rod holding cylinder 7 is arranged to form the sealing conductive portion S. Reference numeral 9 is an electrode fixedly provided on the tip of the internal lead rod 3.

The sealing conductive portion S constructed as described above is inserted and arranged in the sealing tube portion 81 of the glass sealing body 8 so that the electrode 9 is positioned inside the light emitting space surrounding portion 82 of the sealing body 8. Then, the sealing body 8 in which the conductive portion S for sealing is inserted and arranged,
For example, 100 r. p. m. While rotating in the circumferential direction at a moderate speed, heat treatment is performed from the outside of the sealing tube portion 81 using a burner or the like, and the sealing tube portion 81 is heated.
The inner circumference and the outer circumference of the glass member 1 are hermetically welded via the metal foil 2. On the base end side of the inner lead rod 4,
The glass in the portion of the sealing tube portion 81 facing the internal lead rod holding cylinder 6 is heated and pressed, or the sealing tube portion 8
By applying a negative pressure to the inside of the tube 1 and welding it to the inner lead rod holding cylindrical body 6 by this negative pressure, a narrowed portion K is formed, and at the outer end portion of the sealing tube portion 81, the outer end portion is formed. The exposed portion of the metal foil 2 is covered with the glass by heating and melting the part of the glass. Further, also in the other sealing tube portion, the sealing conductive portion configured similarly to the sealing conductive portion S is connected in the same manner as described above.

[0007]

However, the conventional high-pressure mercury lamp having the above-mentioned structure is usually used for a current of 50 to 150 A. For example, a high-pressure mercury lamp for a large current of 200 A or more is manufactured. Then, the following problems occur.

(1) In a high-pressure mercury lamp for large current, since the electrode 9 needs a large heat capacity, for example, an electrode of 500 g or more is used. Such an electrode 9
Since the weight of the electrode 9 side is larger than the weight of the external lead rod 5 side in the sealing conductive portion S where is installed, the external lead rod 5 side and the electrode 9 side cannot be balanced, and As shown, the electrode 9 side is arranged in the sealing tube portion 81 of the sealing body 8 with the electrode 9 side inclined downward with respect to the axial direction of the sealing body 8. When the sealing body 8 in which the sealing conductive portion S is arranged is rotated in the circumferential direction by the glass lathe in such a state, the centrifugal force causes the metal foil 2 to be pulled in the extending direction,
As a result, the metal foil 2 is cut.

(2) In the step of connecting the sealing tube portion 81 and the conductive portion S for sealing, the portion of the sealing tube portion 81 facing the internal lead rod holding cylinder 6 is heated uniformly over its entire area. The subsequent portion on the side of the light emitting space surrounding portion 82 is also similarly heated. For this reason, as shown in FIG. 6, the sealing tube portion 81 includes the internal lead rod holding cylindrical body 6
The deformed portion H is generated at the end portion of the light emitting space surrounding portion 82 side opposite to the portion, and in this state, the deformed portion H is welded to the internal lead rod holding cylinder. As a result, the high-pressure mercury lamp is not able to have a long service life due to cracks or the like in the sealing tube portion 81 during its lighting.

The present invention has been made in view of the above circumstances, and its purpose is to use a large current,
A discharge lamp capable of obtaining a long service life without the metal foil being cut in the step of connecting the conductive part for sealing and the sealing tube portion, and without causing an accident in the glass portion of the sealing tube portion. To provide.

[0011]

DISCLOSURE OF THE INVENTION The discharge lamp of the present invention comprises:
A glass envelope composed of a light emitting space surrounding portion and a sealing tube portion following the light emitting space, and arranged inside the sealing tube portion of the sealing body,
A columnar glass member in which the light emitting space surrounding portion side is narrowed in a tapered shape, a metal plate arranged on one side facing the light emitting space surrounding portion side of the glass member, and a base end is solidified on the metal plate, An inner lead rod whose tip is arranged to extend into the light emitting space surrounding portion, an electrode provided at the tip of the inner lead rod, an outer circumference of the inner lead rod and an inner circumference of the sealing tube portion of the envelope. A glass cylindrical body arranged between the glass member, an external lead rod arranged on the other side facing the outer end side of the sealing tube portion of the glass member, and extending along the outer periphery of the glass member, one end of which Part has a metal foil electrically connected to the external lead rod, and the other end has a metal foil electrically connected to the external lead rod, and the glass cylinder has an outer diameter of one end surface on the metal plate side. Is substantially the same as the diameter of the metal plate, and Its outer diameter upon which to cover the tapered portion of the lath member is characterized in that it conforms to the inner diameter of the sealed tube portion.

Further, the glass cylindrical body has a groove-like recess on the other end surface on the light emitting space surrounding portion side, and the outer diameter of the other end surface conforms to the inner diameter of the sealing tube portion. Characterize.

[0013]

With the glass cylinder disposed between the outer circumference of the inner lead rod and the inner circumference of the sealing tube portion of the sealing body, the outer diameter of the barrel portion matches the inner diameter of the sealing tube portion. When the sealing conductive part is arranged in the sealing tube part, the degree of inclination of the sealing body with respect to the axial direction is small, and as a result, of the metal foil in the connecting step between the sealing conductive part and the sealing tube part. It can prevent disconnection.

Further, since the outer diameter of the one end surface on the metal plate side of the glass cylindrical body is substantially the same as the diameter of the metal plate and covers a part of the outer peripheral surface of the glass member, both of them are assembled. The sealing tube portion of the sealing body can be welded while the temperature is stable.

Further, the glass cylinder body has a grooved recess on the other end surface on the light emitting space surrounding portion side, and since the outer diameter of the other end surface conforms to the inner diameter of the sealing tube portion, it is sealed. On the side of the light emitting space surrounding portion of the tube portion facing the glass tubular body, the glass tubular body can be welded even when heated with a smaller amount of heat compared to the outer end side, as a result,
It is possible to perform welding without deforming the end portion on the light emitting space surrounding portion side of the portion of the sealing tube portion that faces the glass tubular body.

[0016]

EXAMPLE An example of the discharge lamp according to the present invention will be described below for the case of constructing a high pressure mercury lamp. FIG. 1 is an explanatory diagram showing one end side of the discharge lamp according to the embodiment. In this figure, 1 is a cylindrical glass member, 2 is a strip-shaped metal foil, 3 is a disk-shaped metal plate, 4 is an internal lead rod holding cylinder, 51 is a dish-shaped metal member, and 6 is an internal lead rod. The holding tubular body 7 is an external lead rod holding tubular body, and these constitute the sealing conductive portion S. Further, 9 is an electrode,
Reference numeral 8 denotes a sealing body that includes a light emitting space surrounding portion 82 and a sealing tube portion 81 that follows it.

The cylindrical glass member 1 has a tapered outer peripheral surface on a peripheral wall 16 of a portion following the one end surface 11 on the side of the light emitting space 82, and a portion on the one end surface 11 side has a truncated cone shape. It is configured. In addition, a hole 13 for installing the external lead rod 5 is formed on the other side surface 12 of the sealing tube portion 81 on the outer end side.

A disk-shaped metal plate 3 having a diameter slightly smaller than the diameter of the one end face 11 is arranged on one end face 11 of the glass member 1, and an internal lead bar 4 is provided at the center of the metal plate 3. It is fixed so as to extend in the axial direction of the envelope 8 toward the light emitting space surrounding portion 82. An electrode 9 is provided at the tip of the internal lead rod 4.

The method of connecting the metal plate 3 and the inner lead bar 4 is not particularly limited, but for example, the metal plate 3 and the inner lead bar 4 may be used.
It is possible to use a method in which the and are welded together, or a method in which a hole is formed in the center of the metal plate 3 and the base end of the inner lead rod 4 is inserted into this hole and both are welded. As a material for forming the metal plate 3, tantalum, niobium,
Refractory metals such as tungsten and molybdenum can be used.

Between the outer circumference of the inner lead rod 4 and the inner circumference of the sealing tube portion 81 of the sealing body 8, a glass-made inner lead rod holding cylinder 6 is arranged.

FIG. 2 is an explanatory view showing an example of the internal lead rod holding cylinder 6. The internal lead rod holding cylinder 6 is
One end portion 65 continuing from the one end surface 61 on the metal plate 3 side is formed in a tapered shape that gradually spreads like a mortar, and a cylindrical body portion 62 formed following this is formed into the internal lead rod holding cylindrical body 6
To the end of the light emitting space surrounding portion 82 side.

The outer diameter D of the body portion 62 is adapted to the inner diameter of the sealing tube portion 81 of the sealing body 8, and preferably,
0.5 mm to 3.0 compared to the inner diameter of the sealing tube portion 81 of the sealing body 8.
The diameter is smaller by mm. The reason is that if the value is smaller than 0.5 mm, the insertion work becomes difficult, and if the value is larger than 3.0, the angle at which the electrode side tilts downward in the sealing work becomes large and the workability deteriorates. Further, it is preferable that the maximum diameter of the electrode is not larger than the outer diameter D of the body portion 62 by 2 mm. This is because the inner diameter of the sealing tube portion 81 should be as close as possible to the value of D, that is, 3 mm or less, so that the insertion becomes extremely difficult when the maximum value of the electrode is close to D + 3 mm. Considering the workability of insertion, the maximum diameter of the electrode is preferably D + 2 (mm) or less. Further, the outer diameter d of the one end surface 61 of the inner lead rod holding cylinder 6 on the metal plate 3 side is substantially the same as the diameter of the metal plate 3.

Further, the inner lead rod holding cylinder 6 has a groove-like recess 64 on the other end face 63 on the light emitting space surrounding portion 82 side, and in particular, the outer peripheral edge 66 of the other end face 63 has a knife edge shape. Is preferably formed.

A stopper 41 made of molybdenum wire, which is wound around the outer circumference of the inner lead rod 4, is provided at the end of the inner hole of the inner lead rod holding cylinder 6 on the side of the light emitting space surrounding portion 82. The internal lead rod holding cylinder 6
It is possible to prevent the displacement of the position.

An outer lead bar 5 having an outer diameter suitable for this is inserted into the hole 13 of the glass member 1, and the other end face 12 of the glass member 1 is provided at the bottom so as to be connected to the outer lead bar 5. A dish-shaped metal member 51 having holes is arranged,
The external lead rod holding cylinder 7 made of glass is arranged via the metal member 51. Examples of the material for forming the metal member 51 include molybdenum.

On the outer periphery of the glass member 1, for example, six strip-shaped molybdenum-made metal foils 2 extending in the axial direction of the glass member 1 are arranged apart from each other in the circumferential direction. Each one end 21 extends along the tapered portion of the peripheral wall 16 of the glass member 1, and is further connected to the metal plate 3 arranged at the base end of the inner lead rod 3 by means such as spot welding. . The other end 22 of each metal foil 2 is connected to the metal member 51.

As shown in FIG. 3 (a), the tip end edge of each one end 21 of the metal foil 2 has a notch shape having a radius of curvature substantially the same as the radius of curvature of the outer peripheral surface of the inner lead rod 4. An arcuate recess A is formed, and the metal foil 2 is welded to the metal plate 3 in a state where the arcuate recess A is brought into contact with the outer peripheral surface of the inner lead bar 4.

Further, each of the metal foils 2 has both side edges 23, 24 of one end side portion connected to the one end portion 21 connected to the metal plate 3.
Is formed as a hypotenuse portion L whose width becomes smaller toward the one end portion 21, and the hypotenuse portion L is formed as shown in FIG.
As shown in, it is formed in a knife edge shape. Moreover, as shown in FIG. 3C, the hypotenuse portion L is located on the tapered outer peripheral surface of the peripheral wall 16 of the glass member 1.

Then, the sealing tube portion 8 is rotated while rotating the sealing body 8 on which the conductive portion S for sealing is arranged by, for example, a glass lathe.
1 is heat-treated from the outside, the outer periphery of the glass member 1 and the inner periphery of the sealing tube portion 81 are hermetically welded via the metal foil 2, and the outer periphery of the inner lead rod holding cylindrical body 6 and the sealing tube. The inner periphery of the portion 81 is welded without forming the narrowed portion K. Also in the other sealing tube portion, although not shown, the sealing conductive portion configured similarly to the sealing conductive portion S is connected in the same manner as described above.

According to the above embodiment, the inner lead rod holding cylinder 6 arranged between the outer periphery of the inner lead rod 4 and the inner periphery of the sealing tube portion 81 of the sealing body 8 has the body portion 62 thereof. Since the outer diameter of the sealing tube portion 81 matches the inner diameter of the sealing tube portion 81, when the sealing conductive portion S is arranged in the sealing tube portion 81, even if the sealing body 8 is tilted with respect to the axial direction, the degree thereof is small. As a result, it is possible to prevent the metal foil 2 from being cut in the process of connecting the sealing conductive portion S and the sealing tube portion 81.

In addition, the inner lead rod holding cylinder 6 has an outer diameter of one end surface 61 on the metal plate 3 side which is substantially the same as the diameter of the metal plate 3, and is different from the tapered outer peripheral surface of the glass member 1. Since it has a shape that fills the space generated between the sealing tube portions 81, the glass member 1, the internal lead rod holding cylinder 6 and the sealing tube portion 81 can be welded together without a gap.

Further, the inner lead rod holding cylinder 6 has a recess 64 on the other end surface 63 on the light emitting space surrounding portion 82 side, and the outer diameter of the other end surface 63 is the inner diameter of the sealing tube portion 81. Therefore, on the light emitting space surrounding portion 82 side of the portion of the sealing tube portion 81 facing the inner lead rod holding cylinder 6, even if the inner lead rod holding portion 82 side is heated with a smaller amount of heat than the outer end side. The tube body 6 for sealing and the sealing tube portion 81 can be welded together, and as a result, the end of the sealing tube portion 81 on the side of the light emitting space surrounding portion 82 facing the internal lead rod holding tube body 6 is not deformed. Can be welded to.

Although one embodiment of the present invention has been described above, various modifications can be made in the present invention. For example, in the inner lead rod holding cylinder 6, the outer diameter d of the one end surface 61 is substantially the same as the diameter of the metal plate 3, and the outer diameter D of the body portion 62 is the sealing tube portion 81. If it matches the inner diameter,
Other shapes can be used.

The outer shape of the glass member 1 is not limited to a cylindrical shape, and may be appropriately selected depending on the number of the metal foils 2 to be used, and may be, for example, an octagonal pillar shape, a hexagonal pillar shape, or the like.
In addition, the other end 22 of the metal foil 2 is used without using the metal member 51.
May be directly connected to the outer circumference of the external lead rod 5.

The hermetically sealed structure described above can also be used for other lamps that require a large current.

[0036]

As described above, according to the present invention,
Provided is a discharge lamp capable of obtaining a long service life without breaking the metal foil in the sealing tube portion sealing process even in the case of a large current, without causing an accident in the glass portion of the sealing tube portion. be able to.

[Brief description of drawings]

FIG. 1 is an explanatory vertical sectional front view showing a main part of an embodiment of the present invention.

FIG. 2 is an explanatory view showing an example of an internal lead rod holding cylinder.

FIG. 3 is an explanatory diagram showing an example of a metal foil.

FIG. 4 is an explanatory vertical sectional front view showing the configuration of a conventional discharge lamp having a foil seal structure.

FIG. 5 is an explanatory view showing a state in which a sealing conductive portion is arranged in a sealing tube portion of a sealing body in a conventional discharge lamp having a foil sealing structure.

FIG. 6 is an explanatory view showing a deformed portion of a sealing tube portion which occurs in a conventional discharge lamp having a foil seal structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass member 11 One end surface 12 The other end surface 13 Hole 16 Circumferential wall 2 Metal foil 21 One end portion 22 The other end portion 3 Metal plate 4 Internal lead rod 41 Stopper 5 External lead rod 51 Metal member 6 Internal lead rod holding cylinder 61 One end face 62 Body 63 Other end surface 64 Recess 65 One end 66 Outer peripheral edge of the other end surface 7 External lead rod holding cylinder 8 Encapsulation 81 Sealing tube part 82 Light emitting space surrounding part 9 Electrode A Arc-shaped recess B Bottom wall D Body Outer diameter d Outer diameter of one end surface H Deformation part K Constriction part L Inclined part S Sealing conductive part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makichi Makichi 1194 Sado, Bessho-cho, Himeji-shi, Hyogo Ushio Electric Co., Ltd.

Claims (3)

[Claims] 1. A glass sealing body comprising a light emitting space surrounding portion and a sealing tube portion following the light emitting space surrounding portion, and a columnar column disposed inside the sealing pipe portion of the sealing body and tapered toward the light emitting space surrounding portion. Glass member, a metal plate disposed on one side of the glass member facing the light emitting space surrounding portion side, a base end is fixed to the metal plate, and a tip end is arranged so as to extend into the light emitting space surrounding portion. An inner lead rod, an electrode provided at the tip of the inner lead rod, and a glass tubular body arranged between the outer periphery of the inner lead rod and the inner periphery of the sealing tube portion of the sealing body, An external lead rod arranged on the other side facing the outer end of the sealing tube of the glass member, and extending along the outer periphery of the glass member, one end of which is connected to a metal plate, and the other end of which is A metal foil electrically connected to the outer lead bar The outer diameter of the one end surface of the glass plate side of the glass plate is substantially the same as the diameter of the metal plate, and the body portion following the one end surface is a tapered portion of the glass member. The discharge lamp is characterized in that the outer diameter thereof matches the inner diameter of the sealing tube portion. 2. The glass cylindrical body has a groove-like recess on the other end surface on the light emitting space surrounding portion side, and the outer diameter of the other end surface conforms to the inner diameter of the sealing tube portion. The discharge lamp according to claim 1. 3. The maximum diameter of the electrode is smaller than the inner diameter of the sealing tube portion and is equal to or less than a value obtained by adding 2 mm to the outer diameter of the glass tubular body, and the outer diameter of the glass tubular body and the inner diameter of the sealing tube portion. Difference from
The discharge lamp according to claim 1 or 2, which satisfies each condition of mm or less.