JP4062646B2 - Method and apparatus for manufacturing metal halide lamp - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a metal halide lamp employed as a light source for a headlamp of an automobile or a light source for a liquid crystal projector, and particularly relates to a manufacturing method and a manufacturing apparatus for manufacturing the metal halide lamp.
[0002]
[Prior art]
FIG. 3 shows an example of a conventional metal halide lamp manufacturing method and manufacturing apparatus 80. In this state, metal halide grains 92 are placed in the discharge chamber 91 of the bulb 90 where the primary sealing portion 90a is formed. The discharge chamber 91 and the secondary sealing portion 90b are partitioned by a partition plate 81, liquid nitrogen N is blown from the supply device 82 to the discharge chamber 91 side to cool, and the secondary sealing portion 90b side is burner 83. It heats and fuse | melts, and it manufactures by performing the pinch seal process etc. to the secondary sealing part 90b with the pinch sealing machine 84 after that.
[0003]
[Problems to be solved by the invention]
However, in the above-described conventional manufacturing method, when the secondary sealing portion 90b is heated by the burner 83, the valve 90 must be rotated about the axis Z so that the entire circumference thereof is heated uniformly. Therefore, the metal halide grains 92 placed in the discharge chamber 91 move with the rotation of the bulb 90.
[0004]
At this time, if the movement of the metal halide grains 92 occurs in a direction approaching the partition plate 81, the metal halide grains 92 are melted and evaporated by the heat of the burner 83, and sealing is performed by the pinch sealer 84 as shown in FIG. The evaporated metal halide 92a adheres to the inner wall of the previous secondary sealing portion 90b, the electrode 93, the molybdenum foil 94, or the like, which causes a problem of impairing the airtight characteristics after the pinch seal is performed.
[0005]
Of course, when the transition to the secondary sealing portion 90b occurs in the metal halide grains 92 as described above, the amount of metal halide in the discharge chamber 91 becomes insufficient. As a result, there is a problem that the yield of the metal halide lamp is lowered, and the solution of these points has been a problem.
[0006]
In order to prevent movement of the metal halide grains 92 accompanying the rotation of the valve 90 from occurring in the direction of the secondary sealing portion 90b, the secondary sealing portion 90b is moved by the burner 91 in a state where the axis Z of the valve 90 is vertical. A method of heating has also been proposed. In this case, the purpose for the metal halide grains 92 is certainly achieved, but on the other hand, the secondary sealing portion 90b is caused by the convection action of the atmosphere. The uniform heating is extremely difficult, and a sealing failure is caused for this reason, which cannot be a radical solution.
[0007]
[Means for Solving the Problems]
The present invention provides a metal halide lamp manufacturing method in which a metal halide is placed in a discharge chamber of a primary sealed bulb and subjected to secondary sealing as a specific means for solving the above-described conventional problems. By providing a method for manufacturing a metal halide lamp, wherein a position regulating step for preventing the metal halide from moving to a position near the position where the secondary sealing is performed is performed before performing the next sealing. It solves the problem.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Below, this invention is demonstrated in detail based on embodiment shown in a figure. FIG. 1 shows a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a bulb. The bulb 1 has a primary sealing portion 1a already formed at one end, and a discharge chamber 2 is shown. As in the conventional example, the metal halide grains 3 are placed in the second sealing portion 1b to form the secondary sealing portion 1b.
[0009]
Here, in the present invention, when forming the secondary sealing portion 1b, the metal halide grains 3 are devised so as not to move in the vicinity of the secondary sealing portion 1b. This first embodiment In the method, a fixing process is performed on the metal halide grains 3 prior to the process of forming the secondary sealing portion 1b.
[0010]
In the fixing step, the metal halide grains 3 are heated and melted at a temperature at which evaporation does not occur, and are in close contact with the inner wall of the bulb 1 (discharge chamber 2). Fixing is performed so that no movement occurs at the degree of rotation applied to the valve 1 in the forming process.
[0011]
In this first embodiment, the heating method for the metal halide grains 3 is shown as an example using a YAG laser device 20 that can heat the target in a spot shape, but a partition plate 11 is provided as shown in the figure. If appropriate means such as cooling the primary sealing portion 1a with liquid nitrogen N is applied, for example, a heater or the like can be implemented without causing thermal distortion in the primary sealing portion 1a.
[0012]
In this way, after the metal halide grains 3 are temporarily fixed, the secondary sealing portion 1b is formed. At this time, the metal halide grains 3 do not move even when the valve 1 rotates. Therefore, as in the conventional example, when the secondary sealing portion 1b is heated with the central axis Z of the bulb 1 in a horizontal state, the inner wall of the bulb 1, the electrode 4 or the molybdenum foil 5 is also applied. The secondary sealing portion 1b can be formed without causing metal halide adhesion.
[0013]
Therefore, in this first embodiment, not only the occurrence of slow leak due to evaporation and adhesion of metal halide can be prevented, but also the horizontal state that is most favorable for the occurrence of slow leak due to thermal distortion of the valve 1 The secondary sealing portion 1b can be formed in the above-described manner, so that it is possible to reliably prevent the occurrence of an initial failure due to a slow leak that occurs after shipment to the market.
[0014]
Accordingly, although not shown, when forming the secondary sealing portion 1b such as a chuck for supporting the valve 1, a burner, a pinch sealing machine, a supply device of liquid nitrogen N, or an exhaust device in the valve 1. The manufacturing apparatus (refer to FIG. 3 of the conventional example) required for the conventional example can be the same as the conventional example.
[0015]
FIG. 2 shows a second embodiment of the present invention. In the first embodiment, the metal halide grains 3 are temporarily fixed through a process of heating and remelting the metal halide grains 3. In short, the metal halide grains 3 do not have to move to the vicinity of the secondary sealing portion 1b in the formation process of the secondary sealing portion 1b, and even if the movement occurs in other parts, it is substantially hindered. There is nothing.
[0016]
That is, as described in the section of the conventional example, if the central axis Z of the valve 1 is vertical with the secondary sealing portion 1b side upward, the condition is satisfied at least in terms of inhibiting evaporation of the metal halide grains 3b. Become. It was this second embodiment that was made paying attention to this point, and as a result of experiments and studies for achieving the present invention, the inventor determined the inclination angle α of the central axis Z of the valve as the secondary sealing portion. If it is kept in the range of 10 ° ± 5 ° with the 1b side facing upward, the metal halide grains 3 do not approach the vicinity of the secondary sealing portion 1b in the step of forming the secondary sealing portion 1b, and It has been found that irregular heat distortion does not occur in the formation process of the secondary sealing portion 1b.
[0017]
Also in the second embodiment, in forming the secondary sealing portion 1b, the partition plate 11 provided between the discharge chamber 2 and the secondary sealing portion 1b and the portion of the discharge chamber 2 with liquid nitrogen are used. A supply device 12 for cooling by injecting N or the like, a burner 13 for heating the portion of the secondary sealing portion 1b, a pinch sealing machine 14 for pinch-sealing the heated portion of the secondary sealing portion 1b, and the like The manufacturing apparatus 10 consisting of is similar to the previous first embodiment and the conventional example.
[0018]
Here, if the actual implementation of the process of forming the secondary sealing portion 1b is described, for example, a chuck, a burner for supporting the valve 1, conventionally used in this type of process, The entire manufacturing apparatus 10 required for forming the secondary sealing portion 1b, such as a pinch sealing machine, a supply device of liquid nitrogen N, or an exhaust device in the valve 1, is 10 ° ± 5 ° described above. What is necessary is just to incline so that the secondary sealing portion 1b is in the upper range, and other additional devices and additional processes such as the YAG laser device 20 described in the previous first embodiment are also required. It will be able to be implemented soon.
[0019]
【The invention's effect】
As described above, according to the present invention, a metal halide lamp manufacturing method in which a position regulating step for preventing the metal halide from moving to the vicinity of the position where the secondary sealing is performed is performed before the secondary sealing is performed. As a result, the metal halide grains move to the vicinity of the secondary sealing portion by the rotation given to the valve when performing the secondary sealing, the heating is performed, the melted and evaporated, and then the pinch seal should be closely contacted The metal halide adheres to the inner surface of the bulb, thereby reducing the sealing degree and preventing the occurrence of a defect at a relatively early time after shipment, which is referred to as the initial defect due to slow leaks, etc., and the reliability of the metal halide lamp It is very effective for improvement.
[0020]
In particular, the position regulating step is added by a step of inclining the inclination angle α in the range of 10 ° ± 5 ° so that the end of the valve shaft on the side where the secondary sealing is performed is upward. The apparatus can achieve the above-mentioned purpose without any additional process, and has an excellent effect of being able to supply products with excellent quality to the market at a low cost.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a main part of a first embodiment of a method for producing a metal halide lamp according to the present invention.
FIG. 2 is an explanatory view showing the main part of a second embodiment of the method for producing a metal halide lamp according to the present invention.
FIG. 3 is an explanatory diagram showing a conventional example.
FIG. 4 is an explanatory view showing a problem in a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Bulb 1a ... Primary sealing part 1b ... Secondary sealing part 2 ... Discharge chamber 3 ... Metal halide grain 4 ... Electrode 5 ... Molybdenum foil 10 ... Manufacturing apparatus 11 ... Partition plate 12 ... ... Supply device 13 ... Burner 14 ... Pinch seal machine 20 ... YAG laser device

Claims (2)

  A metal halide is placed in the discharge chamber of the primary sealed bulb, a partition plate is provided between the discharge chamber and the secondary sealing portion, and the discharge chamber is cooled while rotating around the bulb axis. In the method of manufacturing a metal halide lamp, wherein the secondary sealing portion is heated at the same time as the second sealing, and then the secondary sealing is performed with a pinch seal after the heating. The metal halide lamp manufacturing method is characterized in that a position restricting step for preventing movement to the vicinity of the position where the valve is performed is performed, wherein the position restricting step includes the secondary sealing of the axis of the bulb. A method of manufacturing a metal halide lamp, which is a step of tilting by 10 ° ± 5 ° so that an end portion to be performed is upward.   A metal halide is placed in the discharge chamber of the primary sealed bulb, a partition plate is provided between the discharge chamber and the secondary sealing portion, and the discharge chamber is cooled while rotating around the bulb axis. At the same time, in the metal halide lamp manufacturing apparatus that heats the secondary sealing portion and performs secondary sealing with a pinch seal after heating, the manufacturing apparatus has an end on the side where the secondary sealing is performed on the axis of the bulb An apparatus for producing a metal halide lamp, wherein the secondary sealing is performed by tilting 10 ° ± 5 ° so as to be upward.

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