JPH11354076A - Discharge lamp and its sealing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the effects of degradation of a sealing glass material to seal an opening part of an arc tube and thereby improve the durability by forming an amorphous part, that is transformed into an amorphous state through quenching after being melted into the sealing glass material, thus sealing the opening part. SOLUTION: A sealing glass material 16a is provided with an amorphous part 16b transformed into an amorphous state by being quenched in a sealing process on the boundary relative to the peripheral part of a sealing base part 15a and the boundary relative to the inside wall of a small diameter part 13, and other parts are brought into a crystallized state. That is, the sealing glass material 16a is heated from ordinary temperature to its melting point by irradiating an infrared-ray and being quenched to its glass transition temperature, after the heating in a sealing process. Thereby, at least the sealing part of the molten sealing glass material 16a becomes the amorphous part 16b transformed into an amorphous state without being recrystallized. Thereafter, it is gradually cooled from the glass transition temperature to ordinary temperature, and a part between the opening of an arc tube and an electrode member is sealed through the sealing glass material 16a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp in which an electrode member is sealed at an opening in an arc tube containing a luminescent substance, and a method of sealing the same.

[0002]

2. Description of the Related Art Conventionally, in a discharge lamp of this type, an electrode member having a pair of electrodes is fixed to an opening of an arc tube made of a translucent ceramic, so that mercury, an inert gas, metal It is known to hermetically enclose a luminescent substance such as a halide. In such a discharge lamp, as a means for hermetically sealing the opening of the arc tube, for example, there is a means of melting a sealing glass material such as a glass frit in a gap between the electrode member and the opening of the arc tube and then solidifying the material.

[0003]

However, according to the prior art, when the discharge lamp is used for a long time, a part of the luminescent substance sealed in the arc tube chemically reacts with the sealing glass material to seal. There is a problem in that the glass material is deteriorated, which adversely affects the light emission characteristics of the arc tube.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and reduces the influence of deterioration of a sealing glass material for sealing an opening of an arc tube, thereby providing a discharge lamp having excellent durability. An object of the present invention is to provide a sealing method.

[0005]

Means for Solving the Problems and Action / Effect of the Invention According to a first aspect of the present invention, a luminous substance is introduced through an opening of an arc tube and the sealing glass material is melted. In the discharge lamp that seals the opening, the sealing glass material has an amorphous portion that is melted and rapidly cooled to be amorphous to seal the opening.

[0006] In the discharge lamp according to the first invention, a luminescent substance is put into the opening of the arc tube, and the opening is sealed with a sealing glass material. The sealing glass material is made amorphous by being rapidly cooled after being melted. The sealing glass material which has been made amorphous in this way has little thermal deterioration even when it is exposed to a high-temperature thermal cycle during the lighting operation of the discharge lamp. Therefore, a discharge lamp having excellent durability can be obtained.

In a preferred aspect according to the first invention, a large-diameter portion having a hollow chamber containing a luminous substance is provided in a discharge lamp for charging a luminous substance through an opening of an arc tube and sealing the opening. A light-emitting tube having a small-diameter portion extending from the large-diameter portion and forming a small-diameter chamber communicating with the hollow chamber; a sealing base inserted into an opening of the small-diameter portion; An electrode member having a lead portion facing the hollow chamber and having a gap between the inner wall of the small-diameter portion and an electrode portion provided at the other end of the lead portion; And a sealing glass material interposed between the inner wall of the base and the outer surface of the sealing base to seal the outside of the arc tube and the hollow chamber.

The entire sealing glass material may be made amorphous. However, since a portion particularly susceptible to a thermal cycle during the operation of the discharge lamp during lighting is a portion in contact with the opening of the small diameter portion. Is preferably formed at least in this portion.

In a second aspect of the present invention, there is provided a method for sealing a discharge lamp in which a luminescent substance is introduced through an opening of an arc tube and a sealing glass material is melted to seal the opening. A setting step of setting a sealing glass material in a peripheral portion, a melting step of melting the sealing glass material, and a quenching step of amorphously sealing the opening by rapidly cooling the melted sealing glass material, It is characterized by having.

The second invention is a method of manufacturing the first discharge lamp, which is a method of melting a sealing glass material and then rapidly cooling the glass material to make it amorphous.

As a step of melting the sealing glass material, it is preferable to use a step of melting only the sealing glass material by irradiating infrared rays concentrated only on the sealing glass material. Irradiation, the arc tube is heated to scatter the luminescent substance to the outside, and the sealing glass material can be easily heated and cooled rapidly, and can be easily made amorphous.

Here, the sealing glass material slightly varies depending on the type of glass, but it is necessary to rapidly cool at least the melting point to the glass transition temperature.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to further clarify the configuration and operation of the present invention described above, a preferred embodiment of the present invention will be described below.

FIG. 1 is a sectional view showing a discharge lamp 10 according to one embodiment of the present invention. In FIG. 1, a discharge lamp 10
Includes an arc tube 11, a light emitting substance filled in the arc tube 11, and an electrode member 15. The arc tube 11 has a large-diameter portion 12 having a hollow chamber 12a filled with a luminescent substance, and small-diameter portions 13 extending from both sides of the large-diameter portion 12, respectively.

The large diameter portion 12 is substantially elliptical spherical.
The thickness of the tube wall is formed to be constant. Small diameter part 13
Are formed continuously at both ends of the large diameter portion 12 as thin tubes, respectively, and the inner space thereof is a thin tube chamber 13a. Further, at both ends of the small-diameter portion 13, the capillary chamber 13 is provided.
An opening 13b that opens a to the outside is formed.

As a material of the arc tube 11, a translucent material such as alumina, alumina-yttria garnet, and quartz glass can be used. When DyI ₃ , CsI, TlI, NaI, or the like is used as the light-emitting substance, it is preferable to use alumina as a main raw material in consideration of its high reactivity. As a method for manufacturing such an arc tube 11, for example, a slurry containing alumina as a main raw material is formed, and this can be integrally formed with the large-diameter portion 12 and the small-diameter portion 13 by casting. It is easy to form the small-diameter portion 13 continuous with the large-diameter portion 12 by such casting.

FIG. 2 is an enlarged sectional view showing a main part of the discharge lamp 10 of FIG. As shown in FIG. 2, the opening 13b of the arc tube 11 is sealed with an electrode member 15 and a sealing glass material 16a. The electrode member 15 includes a sealing base 15a inserted into the opening 13b, a lead 15b provided from the end of the sealing base 15a to the hollow chamber 12a through the capillary chamber 13a, and a lead 15b. And an electrode portion 15c provided at the tip. The sealing base 15a
Is also used as a terminal connected to an external lead wire (not shown), and is supplied with power by being connected to the external lead wire. The lead portion 15b extends axially through the center of the capillary chamber 13a with a predetermined gap between the lead portion 15b and the inner wall surface of the small diameter portion 13. Further, the electrode portion 15c is connected to the lead portion 1
It is wound in a coil shape around the tip of 5b, and discharges at a discharge distance from the opposing electrode 15c.

The following materials can be used as the materials of the electrode member 15. That is, as the sealing base 15a,
Metals such as Nb and Re, alloys such as Nb-Zr, and metal-B
A material having a similar thermal expansion coefficient to that of the material of the arc tube 11, such as a cermet or a cermet such as a metal-C (N) -based metal or a metal-Si-based material can be used. The lead 15b and the electrode 15
As c, high melting point W, Mo or the like can be used.

The sealing base 15a of the electrode member 15 is
By sealing the sealing glass material 16a between the inner wall surface of the opening 13b and the inside, the inside of the arc tube 11 and the outside are sealed in an airtight state. As a material of the sealing glass material 16a, Si
O ₂ —Al ₂ O ₃ —MgO system, Al ₂ O ₃ —CaO—Y ₂ O ₃
Various types, such as an Al ₂ O ₃ —SiO ₂ —Dy ₂ O ₃ type, can be used in accordance with physical properties such as a coefficient of thermal expansion with the material of the arc tube 11. FIG. 3 is an enlarged sectional view showing a peripheral portion of the sealing glass material 16a. The sealing glass material 16a is
a at the boundary with the outer peripheral portion, and at the boundary with the inner wall of the small-diameter portion 13, an amorphous portion 16b that has been made amorphous by being rapidly cooled during a sealing step described later;
Other parts are in a crystallized state.

Next, such a process for sealing the end of the arc tube 11 is performed by a discharge lamp sealing device 30 shown in FIG. FIG. 4 is a schematic configuration diagram showing a discharge lamp sealing device 30 for sealing the end of the arc tube 11, and FIG. 5 is an enlarged sectional view showing a main part of the discharge lamp sealing device 30 of FIG. The discharge lamp sealing device 30 includes an operation box 31, a pass box 33, a heating device 40, an introduction mechanism 50, and a suction and exhaust mechanism 80.

The operation box 31 is provided with operation gloves 32, 32 into which arms are inserted in front of the operation box 31. Through the operation gloves 32, 32, work can be performed in an airtight state in the room. A pass box 33 is provided adjacent to the operation box 31. The pass box 33 and the operation box 31 communicate with each other via a door 31a, and various members carried into the pass box 33 can be carried in by putting hands in the operation gloves 32, 32. I have. The pass box 33 is provided with a door 33a communicating with the outside.
When opened, various members and materials can be carried in from the outside.

As shown in FIG. 5, the heating device 40 is disposed above the operation box 31 via a support plate 52. The heating device 40 includes a housing 4 that forms a heating chamber 41.
2 and an infrared lamp 43 arranged in the heating chamber 41, and a reflection surface 41 a having an infrared reflection function is provided facing the heating chamber 41. The reflecting surface 41a is formed as a concave mirror so as to reflect infrared rays from the infrared lamp 43 and collect the infrared rays from the infrared lamp 43 onto a focusing area, and use a method such as a thermal spraying method or a sputtering method to form platinum, gold, or nickel. Obtained by coating a metal. The reflection surface 41
a is configured to be cooled by a cooling device (not shown).

An introduction mechanism 50 is disposed below the heating device 40. The introduction mechanism 50 is a mechanism for exposing the arc tube 11 to the light-collecting region in the heating chamber 41 from the operation box 31 in an airtight state. The introduction mechanism 50 includes an introduction tube 51 formed of quartz glass or the like, and the operation box 3.
An upper mounting bracket 53 disposed on the upper surface of the mounting box 1 and supporting the introduction pipe 51; a lower mounting bracket 54 that screws the upper mounting bracket 53 to clamp the upper plate 31b of the operation box 31; Seal member 5 interposed between introduction pipe 51
5 and a nut 58 which is fastened by the sealing member 55 so as to seal between the upper mounting member 53 and the introduction pipe 51.
And

The lower mounting bracket 54 and the upper mounting bracket 53
Is formed with a through hole 56.
A support jig 57 can be inserted into and removed from 6. That is,
The support jig 57 has an O-ring 59 on the lower surface of the lower mounting member 54.
And a supporting portion 57b standing upright from the flange portion 57a. A support hole 57c is formed at the upper end of the support portion 57b, and one end of the arc tube 11 is supported by the support hole 57c. The support jig 57 is formed so as to be able to move up and down into the introduction pipe 51 so as to be able to move forward and backward. The mechanism for raising and lowering the support jig 57 can have various configurations such as a manual type, an electric type, and a pneumatic type.

An infrared shielding member 61 is provided on the outer peripheral side of the introduction pipe 51. This infrared shielding member 61
Is a cylindrical body made of Pt so as to reflect infrared light and prevent infrared light from entering the upper part of the arc tube 11, and is provided to a position slightly lower than the height of the electrode member 15 of the arc tube 11.

Returning again to FIG. 4, the discharge lamp sealing device 30
Is provided with a turbo pump P1 and rotary pumps P2, P3, P4 as an intake / exhaust mechanism 80. The turbo pump P1 is a pump for obtaining a high degree of vacuum (10 ^-5 to 10 ^-7 Torr), and the rotary pump P2 is connected in series with the turbo pump P1 to smoothly operate the turbo pump P1 at the time of starting. To do it. Further, the rotary pumps P3 and P4 are provided with a low vacuum (10 ^-1 Torr).
Degree) to obtain a pump.

The turbo pump P1 is connected to the valve V1
Is communicated with the inside of the introduction pipe 51 via a pipe L1 provided with The rotary pump P3 is connected to the pipe L1 via a pipe L2 provided with a valve V2. Also,
The rotary pump P4 is connected to the operation box 31 via a pipe L3 provided with a valve V3.
Is connected to the pass box 33 via a pipe L4 provided with

The pressure in the operation box 31 is measured by a pressure gauge G1, the pressure in the pass box 33 is measured by a pressure gauge G2, and the pressure in the introduction pipe 51 is measured by pressure gauges G3 and G4 attached to the pipe L1. You. Here, the reason why the pressure inside the introduction pipe 51 is measured by the two pressure gauges G3 and G4 is as follows.
The pressure in the chamber fluctuates greatly, so that the measurement range is widened. Further, the operation box 31 is provided with an oxygen concentration analyzer 37 and a moisture meter 38.

On the other hand, a gas circulation purification device 36 is provided adjacent to the operation box 31. The gas circulation purification device 36 is provided with a cooling device 39. The gas circulation purification device 36 and the operation box 31 are connected to the valve V7a,
It is connected by a supply pipe L7 provided with V7b and a return pipe L8 provided with valves V8a and V8b. In the supply pipe L7, a pipe L9 provided with a valve V9 branched from the middle thereof is connected to a pipe L1 connected to the introduction pipe 51.

The gas circulation purifier 36 supplies the Ar gas into the operation box 31 via the supply pipe L7, and takes in the supplied Ar gas into the gas circulation purifier 36 via the return pipe L8. , Incorporated Ar
The oxygen is removed from the gas by a catalytic reaction, and the operation box 31 is removed.
Dew point is -70 ° C or less and residual oxygen is 0.01pp
m so as not to cause a decrease in lamp characteristics.

A pipe L10 provided with a valve V1 and a pipe L11 provided with a valve V11 are connected to the gas circulation purifier 36, and several drops of alcohol are supplied into the gas circulation purifier 36 via the pipe L10. This reduces the residual oxygen in the gas circulation purification device 36, and supplies Ar as a cooling medium from the Ar cylinder 35 to the molecular tube via the pipe L11.

Next, the sealing step of the arc tube 11 will be described. First, the door 31a between the pass box 33 and the operation box 31 shown in FIG. 4 is closed, and the door 33a communicating with the outside of the pass box 33 is opened. Then, various members and materials, that is, luminescent substances such as mercury and iodide, and the luminous tube 11 are carried into the pass box 33 from the outside through the opening of the door 33a. Here, the arc tube 11 is sealed with an electrode member 15 having an electrode attached to one end opening, and the other end is kept open.

Subsequently, the door 33a between the pass box 33 and the outside is closed, the valve V4 is opened, and the inside of the pass box 33 is depressurized by the rotary pump P4.
6 is opened, and the inside of the pass box 33 is replaced with Ar gas.
Subsequently, the door 31a between the pass box 33 and the operation box 31 is opened, and the various members carried into the pass box 33 by the operation gloves 32 are taken into the operation box 31. At this time, the inside of the operation box 31 is set to about 1 atm in advance with Ar. Then, the door 31a between the pass box 33 and the operation box 31 is closed.

Next, with the support jig 57 of the introduction mechanism 50 shown in FIG.
The lower end, which is the lower end of the arc tube 11 and is already sealed with the electrode member 15, is inserted into c, and the arc tube 11 is supported on the support jig 57 in an upright state. After that, the arc tube 1
The luminous substance is weighed from the upper end opening of the luminous tube 1 and the
Inject into. Further, as shown in FIG. 6, an electrode member 15 with an electrode is inserted into the other end opening of the arc tube 11, and in this state, a ring-shaped glass is inserted between the other end opening of the arc tube 11 and the electrode member 15. Set the ring 16c. continue,
The support jig 57 shown in FIG. 5 is raised, the luminous tube 11 supported on the support jig 57 is inserted into the introduction tube 51, and the glass ring 16c is adjusted to the infrared light collecting region.

[0035] In this state, in the closed state of the valve V2 and valve V9 4, by opening the valve V1, to exhaust the Ar gas from the inlet pipe inside 51 in the turbo pump P1, 10 ^-1 ~ Degas to 10 ^-7 Torr, close the valves V1 and V2 and open the valve V9, and supply Ar gas until the inside of the introduction pipe 51 reaches about 30 to 300 Torr.

Subsequently, the infrared lamp 43 is turned on to reflect infrared rays on the reflecting surface 41a, thereby condensing the light on the ring-shaped glass ring 16c, melting the glass ring 16c, and cooling and solidifying the sealing step. (The state shown in FIG. 7). The sealing step is performed based on the timing chart shown in FIG. The solid line in FIG. 8 shows a heating step according to the present embodiment, and the broken line shows a conventional heating step as a comparative example. Irradiation is performed from room temperature by infrared rays to obtain the melting point (M
Heat to p) and maintain at this melting point (Mp) for 25 seconds. As a result, the molten glass ring 16c is placed in the opening 1
3b and between the sealing base 15a. At this time, the inside of the arc tube 11 is still set at 30 to 300 Torr, and when Ar gas is supplied until the outside of the introduction tube 51 reaches about 500 Torr, a pressure difference is generated between the two, and the pressure difference is caused by the pressure difference. Then, the glass ring 16 c melts and enters the gap between the electrode member 15 and the arc tube 11.

After heating at this melting point (Mp), the glass is rapidly cooled to a glass transition temperature Tg in 5 seconds. As a result, as shown in FIG. 3, at least the sealed portion of the molten sealing glass material 16a becomes an amorphous portion 16b that has been made amorphous without recrystallization. At this time, as a means for rapid cooling, a means such as turning off the infrared lamp 43 and spraying a cooling gas on the peripheral portion of the sealing glass material 16a can be used. Subsequently, the temperature is gradually cooled from the glass transition temperature Tg to room temperature. Thereby, the space between the opening of the arc tube 11 and the electrode member 15 is sealed via the sealing glass material 16a.

According to the above embodiment, the sealing glass material 1
6a is heated and melted by irradiating infrared rays, and when sealing the sealing base 15a and the small diameter portion 13 of the electrode member 15, the glass ring 16c is heated and melted, then rapidly cooled, and the sealing glass material 16a is cooled. By making at least the seal portion amorphous, even if a heat cycle is applied to the arc tube 11 at the time of lighting, the adhesive strength of the sealing glass member 16a does not decrease and the sealing force can be maintained.

The present invention is not limited to the above-described embodiment, but can be implemented in various modes without departing from the gist of the invention.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a discharge lamp 10 according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a main part of the discharge lamp 10 of FIG.

FIG. 3 is an enlarged sectional view showing a peripheral portion of a sealing glass material 16a.

FIG. 4 is a schematic configuration diagram showing a discharge lamp sealing device 30 for sealing an end portion of an arc tube 11;

FIG. 5 is an enlarged sectional view showing a main part of the discharge lamp sealing device 30 of FIG.

FIG. 6 is an explanatory view illustrating a sealing step of the arc tube 11;

FIG. 7 is a sectional view showing a state after the arc tube 11 is sealed.

FIG. 8 is a timing chart showing a heating step of the sealing glass material 16a.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Discharge lamp 11 ... Arc tube 12a ... Hollow chamber 12 ... Large diameter part 13 ... Small diameter part 13a ... Narrow tube chamber 13b ... Opening part 15 ... Electrode member 15a ... Sealing base 15b ... Lead part 15c ... Electrode part 16a ... Sealing Glass material 16b ... Amorphous part 16c ... Glass ring 30 ... Discharge lamp sealing device 31 ... Operation box 31a ... Door 31b ... Top plate 32 ... Operation glove 33 ... Pass box 33a ... Door 36 ... Gas circulation purification device 37 ... Oxygen concentration analysis Total 38 38 Moisture meter 39 Cooling device 40 Heating device 41 Heating chamber 41 a Reflective surface 42 Housing 43 43 Infrared lamp 50 Introduction mechanism 51 Introduction pipe 52 Support plate 53 Upper mounting bracket 54 Lower Mounting bracket 55 ... Seal member 56 ... Introduction hole 57 ... Support jig 57a ... Flange 57b ... Support 57c ... Support hole 58 ... Nut 61 ... Infrared shielding Wood 80 ... intake and exhaust mechanism P1 ... turbo pump P2, P3, P4 ... rotary pump V1~V6 ... valve V9, V11 ... valve V7a, V7b ... valve V8a, V8b ... valve L1~L11 ... piping G1~G4 ... pressure gauge

Claims (6)

[Claims] 1. A discharge lamp in which a luminescent substance is introduced through an opening of an arc tube and a sealing glass material is melted to seal the opening, wherein the sealing glass material is rapidly cooled after being melted. A discharge lamp having an amorphous portion which is made amorphous and seals an opening. 2. A discharge lamp in which a luminous substance is inserted through an opening of an arc tube and the opening is sealed, wherein a large-diameter portion having a hollow chamber containing the luminous substance; An arc tube having a small-diameter portion forming a small-diameter chamber communicating with the hollow chamber; a sealing base inserted into an opening of the small-diameter portion; and a sealing base extending from the sealing base toward the hollow chamber and including the small-diameter portion. An electrode member having a lead portion disposed so as to have a gap between the inner wall and an electrode portion provided at the other end of the lead portion; an inner wall of the small diameter portion and an outer surface of the sealing base portion A sealing glass material interposed between and sealing the outside of the arc tube and the hollow chamber, wherein the sealing glass material is amorphous by being cooled rapidly after being melted. Characterized by having an amorphous part sealing the opening Electric light. 3. The discharge lamp according to claim 1, wherein the amorphous portion is formed at least in a portion in contact with an inner wall surface of the opening of the discharge lamp. 4. A method for sealing a discharge lamp in which a luminescent substance is introduced through an opening of an arc tube and a sealing glass material is melted to seal the opening, wherein a sealing glass is provided around the opening. A discharge lamp comprising: a setting step of setting a material; a melting step of melting the sealing glass material; and a quenching step of rapidly cooling the molten sealing glass material to form an amorphous state and seal the opening. Sealing method. 5. The discharge lamp sealing method according to claim 4, wherein the melting step is a step of melting the sealing glass material by irradiating infrared rays to the sealing glass material. 6. The method for sealing a discharge lamp according to claim 4, wherein the cooling step is a step of rapidly cooling at least between a melting point and a glass transition temperature of the sealing glass material.