JPS6111886Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a discharge lamp equipped with a metal capsule for supplying the required amount of mercury to the space inside the bulb.

Generally, during the evacuation process of discharge lamps, a certain amount of mercury is sealed inside the bulb through the exhaust pipe from the exhaust head, but because the temperature of the bulb is high during the evacuation operation, a large amount of mercury is filled in the bulb immediately after it is filled into the bulb. of mercury evaporates. The mercury vapor then dissipates into the vacuum system (exhaust system), and most of it is condensed in the trap, but some of it is released from the vacuum pump to the outside and tends to contaminate the working environment.

In addition, the amount of mercury sealed in the bulb is about 3 to 5 times greater than the required amount, taking into account dissipation into the vacuum system, which is not preferable from the point of view of effective use of resources.

Therefore, as shown in FIGS. 1 and 2, the applicant previously connected an electrode D to the tips of two strut lines C and C extending from a stem B sealed at the end of a bulb A. A ring-shaped metal member F having a space E is disposed near this electrode D, and a metal capsule G is formed by incorporating a required amount of mercury in this metal member F and crushing and sealing the opening. proposed a discharge lamp in which the space E is positioned so as to be bridged, and one crushed part H is welded to a metal member F.

According to this discharge lamp, the mercury in the metal capsule G is supplied to the space inside the bulb by high-frequency heating of the metal member F and the metal capsule G after the exhaust operation is completed, so that mercury vapor is released from the exhaust system to the outside. Therefore, there is no contamination of the working environment, and since the metal capsule G already contains the minimum amount of mercury necessary for a discharge lamp, resources can be used effectively. Furthermore, when the metal member F and the metal capsule G are heated with high frequency, the metal capsule G is smaller than the metal member F and is welded so as to bridge the space E. Since G is heated intensively, excellent effects such as being able to quickly supply mercury to the space inside the bulb can be obtained.

By the way, this metal capsule G has a width of 2, for example.
Although it has an extremely small structure with a total length of ~3 mm, a total length of 5 mm, and a length of the crushed part H of approximately 2 mm, the mercury vapor pressure inside the metal capsule must be high enough to release the built-in mercury into the bulb interior space by high-frequency heating. It must be heated to a sufficiently high temperature so that the sealing force is greater than the sealing force of the crushed portion H. In this respect, since the metal capsule G is welded to the metal member F so that the crushed part H at one end bridges the space E, it is heated more efficiently than the metal member F, and the mercury is heated in a relatively short time. can be supplied to the space inside the valve.

However, since the portion of the metal capsule G other than the crushed portion H is also in contact with the metal member F adjacent to the space E, the high frequency current flowing during high frequency heating is dispersed throughout the metal capsule, and the metal member Although it is heated more efficiently than F, the heating efficiency of the metal capsule G tends to decrease and the time for releasing mercury into the space inside the bulb tends to become longer. For this reason, the heating time of the metal member F becomes longer, and H ₂ , CO ₂ , N ₂ , H ₂ O, O ₂ is released from the metal member F, metal capsule G, etc.
This results in the release of even more impure gases.

These impure gases are successively adsorbed by the phosphor, electrodes, etc. as the lighting time progresses, but especially during the initial period of lighting up to about 100 hours, they act directly or indirectly on the mercury, phosphor, etc. This has the disadvantage that the initial luminous flux, initial starting voltage, and appearance characteristics are affected.

On the other hand, in recent years, extremely high-speed equipment with a working index of about 1 second/unit has been used in the manufacture of discharge lamps. Since it takes a long time, it is necessary to install many heads for high frequency heating, and there is also the disadvantage that the device becomes complicated and it is difficult to apply it to the same device.

In view of these points, the present invention provides a discharge lamp that can supply mercury to the interior of the bulb more quickly during high-frequency heating of a metal capsule, and can reduce the emission of impure gases as much as possible. , Examples will be described below.

In FIGS. 3 to 5, numeral 1 denotes a bulb, and a phosphor 2 is coated on the inner surface of the bulb. 3 is a stem sealed at the end of the valve 1; 4, 4 is a strut line implanted in the stem 3 and extending into the interior space of the valve;
Reference numeral 5 denotes an electrode such as a filament coil connected to the tips of the strut wires 4, 4. Reference numeral 6 denotes a ring-shaped metal member disposed near the electrode 5; in the illustrated example, it is disposed so as to surround the electrode 5;
It can also be arranged so as to be more distant from the non-discharge space side. Reference numeral 7 denotes a non-volatile getter made of, for example, zirconium-aluminum, which is coated on the inner surface of the metal member 6, and may be coated on the outer surface of the metal member 6 and the support wire 4, or may be omitted. 8
is a space formed between the ends 6a and 6b of the metal member 6. Reference numeral 9 denotes a support wire that supports the metal member 6 while electrically insulating it from the support wires 4, 4, and is implanted in the stem 3. In addition, when the metal member 6 is disposed closer to the non-discharge space than the electrode 5, it can be supported by either one of the support wires 4, 4 instead of the support wire 9. Reference numeral 10 denotes a metal capsule welded to the ends 6a and 6b of the metal member 6 so that a space 8 is bridged therein, and includes a bottomed, cylindrical, uncollapsed portion 11, and a crushed portion 12 wider than the uncrushed portion 11. It has a structure in which a required amount of mercury 13 is stored in an uncollapsed portion 11. Incidentally, this metal capsule 10 is manufactured, for example, as shown in FIG. 6. That is, first, as shown in FIG.
0' is made into an inert gas atmosphere, for example, an argon gas atmosphere, and a required amount of mercury 13 is stored in the bottomed cylindrical portion 11. Next, as shown in Figures b and c, a cylindrical opening 12' having a diameter larger than that of the bottomed cylindrical portion 11 is crushed and sealed. After that, the crushed part 1
The two ends are welded to complete the fabrication. 14 is the crushed portion 12 of the metal capsule 10 and the end portion 6 of the metal member 6
A separated part formed between the metal capsule part and the metal member 6 excluding the welded parts with a and 6b, and the crushed part 1
A portion near the non-squashed portion 11 of No. 2 is bent such that the non-squashed portion forms an inclination angle of θ=20 to 70° with respect to the metal member 6.

Next, a method of fixing the metal capsule 10 to the metal member 6 and a method of supplying the mercury 13 to the interior space of the bulb in the metal capsule 10 will be explained. First, a non-volatile getter 7 is applied to the inner surface of an elliptical metal member 6 having a major diameter part and a minor diameter part, and the electrode 5 is surrounded by this metal member 6, and the end of the support wire 9 is attached to a part of the metal member 6. Weld. Then, after bending the portion of the crushed portion 12 of the metal capsule 10 close to the uncrushed portion 11 with respect to the horizontal plane so that θ=20 to 70° (see FIG. 5), The end portion 6 of the metal member 6 is positioned so that the collapsed portion 12 faces the discharge space side and the crushed portion 12 faces the non-discharge space side.
The crushed portions 12 are overlapped and welded to a and 6b so that the space portion 8 is bridged. As a result, a separation part 14 is formed between the uncrushed part 11 of the metal capsule 10 and the metal member 6. Note that the separating portion 14 can also be formed by separating the unsquashed portion 11 from the metal member 6 after welding the metal capsule 10 to the metal member 6. The mount thus constructed is sealed to the end of a bulb 1 whose inner surface is coated with a phosphor 2.

Next, connect this discharge lamp to the exhaust system of the exhaust device,
Exhaust impure gas from the space inside the valve. Then, fill the valve with a certain amount of inert gas, such as argon gas.
Fill to a pressure of 1.5 to 3.5 mmHg and seal the exhaust pipe with a burner. Thereafter, a high-frequency heating coil is arranged around the outer circumference of the bulb 1 so that a loop current flows through a closed circuit consisting of the metal member 6 and the metal capsule 10, and high-frequency heating is performed. Then, a loop current flows through the metal member 6 and the metal capsule 10, but the space 8 of the metal member 6 collapses into the collapsed portion 12.
The loop current is concentrated in the crushed portion 12 because it is bridged by the bridge. For this purpose, the crushing part 12
is heated extremely rapidly compared to the metal member 6 and reaches a high temperature. At the same time, the uncollapsed portion 11 also collapses to the collapsed portion 1.
The temperature becomes high due to heat conduction from 2, etc., and the vapor pressure of the built-in mercury 13 becomes extremely high. When the mercury vapor pressure exceeds the sealing force of the collapsed portion 12,
The crushed portion 12 is formed with an opening that substantially coincides with the axial direction of the bulb 1 and faces toward the non-discharge space, and the mercury 13 in the unsqueezed portion 11 is discharged into the bulb interior space through this opening. This mercury release takes place for about 1 to 2 seconds after high-frequency heating. At this time, if tension is applied to the crushing portion 12 of the metal capsule 10, the capsule can be opened more stably. Impure gas released during high-frequency heating of the metal member 6 and metal capsule 10 is quickly adsorbed by the non-volatile getter 7.
The space inside the valve is kept clean.

In this way, the metal capsule 10 is welded to the ends 6a and 6b of the metal member 6 so that the crushed portion 12 bridges the space 8, but in particular, the non-welded portion of the metal capsule 10 to the metal member 6 ( Since the separation portion 14 is mainly formed in the unsquashed portion 11), the loop current concentrates on the crushed portion 12 during high-frequency heating. For this reason, the crushed portion 12 is heated to a high temperature in an extremely short time compared to the metal member 6, and the uncrushed portion 11 is similarly heated by heat conduction, etc., and the vapor pressure of mercury 13 in the uncrushed portion 11 is heated. is increased to a pressure sufficient to form an opening in the collapsed portion 12 in a short period of time. Therefore, after high frequency heating, approximately 1 to 2
The mercury 13 can be reliably supplied to the bulb interior space in about seconds.

Furthermore, since the time for supplying mercury 13 to the space inside the bulb can be reduced to less than half that of the discharge lamp shown in FIGS. You can achieve your goals. Therefore, for example, if the working index is 1 second/
The present invention can be easily applied to a discharge lamp manufacturing apparatus as high-speed as this without complicating the apparatus.

Further, the end portion 6 of the metal member 6 adjacent to the space portion 8
Since the metal capsule 10 is welded to a and 6b, the metal member 6 is heated by the loop current during high frequency heating, but the metal capsule 10
Because the heating ends in a short time, it is not heated like the metal capsule 10. For this reason, the amount of impure gas generated is reduced, which not only improves the characteristics at the initial stage of lighting, but also effectively improves the luminous flux, appearance characteristics, etc. during the life of the lamp. In particular, if a member that releases less gas is used as the metal member 6, the non-volatile getter 7 can be omitted in addition to the above-mentioned effect of suppressing the release of impurity gas.

Furthermore, when welding the metal capsule 10 to the metal member 6, the crushed portion 12 close to the uncrushed portion 11 of the metal capsule 10 is
is bent in advance at an angle of θ=20 to 70° with respect to the horizontal plane, so that the uncrushed portion 11 is bent against the metal member 6.
The uncollapsed portion 11 is not damaged by the welding electrode and can be easily mounted on the stem. However,
If θ is less than 20°, the uncollapsed portion 11 will come into contact with the metal member 6, and the release of mercury 13 will be significantly impaired. It is not preferable to deviate from this range because the crushed portion 11 may be damaged and the mercury inside will leak, making it impossible to supply the required amount of mercury to the space inside the bulb, and the characteristics of the discharge lamp will be significantly impaired.

Note that the present invention is not limited to the above-mentioned embodiments; for example, the crushing portion of the metal capsule may be configured so that the opening of the bottomed cylindrical body before crushing is wider (larger in diameter) than the cylindrical portion. It can also be made wider by a crushing operation. In addition to having the same thickness throughout, the cylindrical portion can also be made thicker than the collapsed portion. Furthermore, the direction in which the metal capsule is fixed to the metal member can be reversed by 180 degrees, and can be appropriately selected depending on the shape of the metal member.

As described above, according to the present invention, it is possible to provide even more prompt supply of mercury to the space inside the bulb during high-frequency heating of the metal capsule, and it is also possible to improve the characteristics by suppressing the release of impure gas as much as possible. However, in particular, by bending the crushed portion of the metal capsule before fixing it to the metal member, the ease of assembly can be significantly improved.

[Brief explanation of the drawing]

Figure 1 is a cutaway side view of the main parts of a discharge lamp that is the premise of this proposal, Figure 2 is a cross-sectional view of Figure 1, Figure 3 is a cutaway side view of the main parts showing an embodiment of the proposal, and Figure 4. is a cross-sectional view of Fig. 3, and Fig. 5 is a - cross-sectional view of Fig. 4.
The cross-sectional view and FIG. 6 are a front cross-sectional view and a side cross-sectional view for explaining the method of manufacturing the metal capsule. In the figure, 1 is a valve, 3 is a stem, 4 is a strut line,
5 is an electrode, 6 is a metal member, 8 is a space, 10 is a metal capsule, 10' is a bottomed cylindrical body, 11 is an uncollapsed part (cylindrical part), 12 is a crushed part, 12' is an opening, 1
3 is mercury, and 14 is a separation part.

Claims (1)

[Scope of utility model registration request] Electrodes are connected to two strut wires extending from the stem at the end of the bulb, a ring-shaped metal member with a space is disposed near the electrodes, and a bottomed cylindrical member containing mercury is installed in the metal member. A metal capsule made by crushing and sealing the opening of the body wider than the cylindrical part,
The crushed part is fixed so as to bridge the space, and the crushed part close to the uncrushed part is fixed against the metal member for 20 minutes.
A discharge lamp characterized in that an uncollapsed portion bent at an inclination angle of ~70° is separated from a metal member.