JPH0224955A - Arc lamp - Google Patents

Abstract

PURPOSE:To prevent an angular section from being formed in a seal section by continuously connecting a cylindrical supporter corresponding to the shape of the seal section to a cylindrical electrode and proving a conducting piece or the like on the outer periphery of them. CONSTITUTION:When a cylindrical electrode 2 is continuously connected to a cylindrical supporter 3 and a conducting piece 4 and a lead wire 5 are provided on the outer periphery of them, they are formed in a shape corresponding to the cylindrical shape of a seal section 7, a rectangular section is prevented from being formed in the seal section 7. As a result, no residual stress is concentrated, the occurrence of explosion during lighting is prevented. No cut machining of the electrode is required, thus productivity is improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an arc lamp such as a short arc lamp used as a point light source in ultraviolet precision exposure equipment, optical applied analysis equipment, solar simulators, etc. .

[Conventional technology]

A conventional short arc lamp, for example, generally has a structure shown in FIGS. 6 and 7. That is, the electrodes 2 are placed oppositely close to both ends of a tube 1 whose central portion is approximately spherical, the ends of the electrodes 2 are cut to form a flat plate part 9, and the flat plate part 9 is provided with a foil-like shape. Conductive pieces 4 made of molybdenum are overlapped and welded, and lead wires 5 are overlapped and welded to the outer ends of the conductive pieces 4, and placed inside the tube 1.
The interior is vacuumed, heated, and sealed using atmospheric pressure. The bulb 1 is filled with an inert gas such as xenon gas, mercury, or a metal halide in order to radiate the wavelength necessary for discharge light emission.

[Problem to be solved by the invention]

The biggest drawback of conventional arc lamps, particularly short arc lamps, is that the internal pressure within the bulb 1 reaches several tens to 100 atmospheres during one lighting operation, and the bulb 1 often explodes during lighting.

The location where this explosion is most likely to occur is on tube 1.

■Corner part 8 with cutting process at the end of electrode 2. Alternatively, the connecting portion between the end portion and the conductive piece 4, (2) the portion where the conductive piece 4 is connected, and (2) the connecting portion between the conductive piece 4 and the lead wire 5, etc. This is because the sealing part 7 has a cylindrical shape, whereas the electrode 2 sealed in the sealing part 7 has a cylindrical shape. Since the conductive piece 4 does not have a corresponding cylindrical shape, when the sealing part 7 is heated and melted to seal the electrode 2 and the conductive piece 4 under atmospheric pressure, and when the electrode 2 and the conductive piece 4 are cooled after sealing, this occurs in the sealing part 7. This is because residual stress concentrates on the corner portions 8 and the like. This residual stress is 5X107N/n (
As described above, this corresponds to about half of the absolute tensile strength of the quartz glass forming the bulb 1. These areas where residual stress is concentrated are also areas where distortions and cracks are likely to occur frequently.

The explosion of the tube would not only halt the manufacturing process, but also cause the lens to explode, which is a high-quality optical component.

This can also damage filters, shutters, etc., causing great damage. Furthermore, explosions can lead to contamination within the factory, which can also endanger the health of workers.

The present invention was devised in view of these problems, and an object of the present invention is to provide an arc lamp that does not explode during one lighting period.

[Means to solve the problem]

Therefore, the tube 1, the electrode 2, and the support 3.

It is composed of a conductive piece 4 and a lead wire 5.

The bulb 1 was formed by continuously forming a cylindrical sealing part 7 at both ends of a spherical or egg-shaped light-emitting part 6, and sealing mercury or the like in the interior set to a vacuum. The electrodes 2 have a cylindrical shape and are provided in the tube 1 in close opposition to each other.

The pillar body 3 has a cylindrical shape corresponding to the shape of the sealing part 7 , and its outer circumferential surface is connected to the outer end of the electrode 2 in a substantially smooth continuous manner with the outer circumferential surface of the electrode 2 . It was supposed to be enclosed in. The conductive piece 4 is positioned with its inner surface in contact with the outer peripheral surface of the glass column, and its inner end is connected to the outer end of the electrode 2. The lead wire 5 has its inner end connected to the column. 3 Connected to the outer end.

[Effect]

In the present application, as described above, a cylindrical columnar support 3 having the same shape as the electrode 2 is provided continuously to the outer end of the cylindrical electrode 2, and the continuous outer peripheral surface of the two is set to be smooth. Since the conductive piece 4 is provided along the axial direction of the outer peripheral surface of the electrode 2, it is necessary to form a flat plate part 9 at the outer end of the electrode 2 to achieve connection with the conductive piece 4, as in the conventional case. There is no. Therefore, the electrode 2, the conductive piece 4. And the lead wires 5 can be connected linearly without forming the corner portions 8.

As a result, when sealing the sealing part 7 to the part of the tube 1 that contacts the corner part 8 of the electrode 2, or when cooling after sealing, the electrode 2 etc. and the sealing part 7 can be sealed. There is no concentration of residual stress caused by the difference in shrinkage rate of quartz glass, and there is no risk of explosion during lighting.
Its safety is significantly improved. Incidentally, in the arc lamp according to the present invention, the residual stress generated in the sealing portion 7 is less than IXIO''N/i.

Further, cutting of the outer end of the electrode 2, which was conventionally required, can be eliminated, and as a result, productivity can be improved.

〔Example〕

One embodiment is shown in FIGS. 1 and 2. This is a short arc lamp, and FIG. 1 shows the state before the sealing portion 7 is heat-sealed, and FIG. 2 shows the state after heat-sealing. In the short arc lamp shown in this embodiment, one light emitting part 6 is approximately oval shaped, and the sealing part 7 is cylindrical. The electrodes 2 whose inner ends are located close to each other are each set to have a cylindrical shape. The support column 3 connected to the electrode 2 has a cylindrical shape with a diameter equal to that of the electrode 2.

The material is the same quartz glass as the bulb 1 (see Figure 3). In addition to quartz glass, for example, transparent ceramics can also be used. The conductive piece 4 located on the support column 3 is made of foil-like molybdenum.

Its shape is approximately a semicircle whose inner surface abuts the outer circumferential surface of the support column 3 (see FIG. 4). A lead wire 5 is connected to the outer end of the conductive piece 4, and is connected to an external power source.

Incidentally, a plurality of conductive pieces 4 may be provided as shown in FIG. By doing so, the heat generated in the conductive piece 4 can be dispersed throughout the sealing part 7.

There is no risk of explosion occurring due to residual stress acting on weakened parts due to localized heat concentration.

This example was formed as follows. Namely.

Foil-shaped molybdenum is welded to the outer peripheral surface of the cylindrical columnar support 3, and the inner end of the foil-shaped molybdenum is slightly protruded from the support 3, and the assembly of the support 3 and the foil-shaped molybdenum is assembled. , the inner end of the foil molybdenum is butted against the outer end surface of the electrode 2 and welded (spot welded) to the outer peripheral surface of the outer end of the electrode 2.

At this time, be careful not to create a step on the welding surface.

Lead cotton 5 is welded to the outer end of the conductive piece 4.

After this welding process is completed, the sealing part 7 is heated and melted, and the electrode 2.
Strut body 3. Conductive piece 4. The lead wire 5 is sealed.

Note that the present invention is not limited to the short arc lamps shown in the embodiments, but includes arc lamps such as compact arc lamps and long arc lamps.

〔Effect of the invention〕

In this way, the present invention connects a cylindrical support body corresponding to the shape of the sealing part to two cylindrical electrodes in succession, and provides a conductive piece on the outer circumferential surface of the support pillar body. Since corners are prevented from being formed in the lamp, residual stress will not be concentrated, and explosions during lighting can be prevented.

In addition, since cutting of the electrode, which was conventionally required, is no longer necessary, this greatly contributes to improved productivity.

Moreover, by preventing explosions.

It has many excellent effects, such as allowing stable production to be carried out in a planned manner and not having any negative impact on the environment within the factory or the health of employees.

[Brief explanation of the drawing]

Figures 1 to 5 show a short arc lamp which is an embodiment of the present invention. Figure 1 is a cross-sectional view showing the state before the sealing part is sealed by heating. 3 is a sectional view taken along the line A-A in FIG. 1, FIG. 4 is a sectional view taken along the same line B-B, and FIG. 6 is a sectional view showing the prior art, and FIG. 7 is a sectional view taken along the line CC in FIG. 6. Explanation of symbols 1: Tube, 2: Electrode, 3: Strut. 4: conductive piece, 5: lead wire, 6: light emitting section 7: sealing section, 8: corner section, 9: flat plate section. pumpsy

Claims (3)

[Claims] (1) A substantially spherical light emitting part (6) A tube body (1) in which cylindrical sealing parts (7) are continuously formed at both ends, and mercury or the like is sealed in the vacuumed interior; A substantially cylindrical electrode (2) is provided in the tubular body (1) with its tips facing each other; A cylindrical columnar support (3) that is continuously connected and enclosed within the tube (1);
) a conductive piece (4) connected to the outer end and the electrode (2);
An arc lamp consisting of a lead wire (5) whose inner end is connected to the outer end. (2) The arc lamp according to claim 1, comprising a plurality of conductive pieces (4) connected to the electrode (2). (3) The arc lamp according to Claims 1 and 2, wherein the distance between the electrodes (2) is set short, so as to form a so-called short arc lamp.