JP3903706B2 - Lamp power supply structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a power supply structure for a lamp, and more particularly to a power supply structure for a light source lamp of a projector apparatus.
[0002]
[Prior art]
In a discharge lamp such as a short arc type mercury lamp or a metal halide lamp, a metal base (usually also referred to as a base) is fixed to an end of a sealing portion of a lamp made of quartz glass.
FIG. 3 shows such a conventional power feeding structure.
A metal base 20 is attached to the end of the lamp sealing portion 10. The lamp sealing portion 10 is made of quartz glass, and a metal foil 11 is embedded therein, and a lead rod 12 made of molybdenum or the like is welded to the metal foil 11. The lead bar 12 is connected to a metal wire 14 such as nickel using a white copper ribbon 13 or the like. The base 20 includes a large-diameter portion 20a and a small-diameter portion 20b, and the large-diameter portion 20a is connected using such a white copper ribbon. The reason for using the metal wire 14 using the white copper ribbon is that the lead bar 12 is usually hard, and if it is projected too long, the sealing part 10 may be damaged due to unnecessary heavy weight in the manufacturing process. Because there is.
Then, the metal wire 14 connected to the lead bar 12 is electrically contacted by plasma welding or the like at the tip of the small diameter portion 20 b of the base 20. That is, the small-diameter portion 20b of the base 20 has a through-hole enough to allow the metal winding wire to pass through, and the side surface of the metal winding wire is electrically connected to the inner surface of the small-diameter portion 20b of the base by welding. It is possible to configure a power feeding structure capable of electrical conduction from the outer peripheral surface. Normally, in an optical device, the base 20 and the lamp sealing portion 10 must be firmly fixed in order to position the lamp by holding the base 20 in an accurate position. For this reason, the adhesive 15 is filled in the base 20 as a fixing means.
[0003]
However, in such a base feeding structure, the adhesive may leak from the tip of the base (indicated by A in the figure). Such adhesive leakage means that the adhesive is flowing in the small-diameter portion 20b, and weakens the electrical contact between the metal wound wire 14 and the base 20. As a result, even if an electrical connection line from a power source is attached to the base 20, the power feeding function is insufficient. As a result, a lamp lighting failure is caused.
Particularly, since a light source lamp used for a liquid crystal projector or a DLP (digital light processor) is required to be extremely small, it is naturally required that a base attached to the light source lamp is also small.
On the other hand, the sealing part of the discharge lamp requires a power supply metal foil having a desired width in order to obtain predetermined electrical characteristics. It cannot be made smaller. That is, the base is required to have a diameter as small as possible, but the gap between the two is inevitably small due to the fact that the diameter of the lamp sealing portion is increased to some extent.
This causes a decrease in electrical conductivity due to the leakage of the adhesive, together with the difficulty of the adhesive injection work. This is because the adhesive that should originally be injected only into the large-diameter portion 20a of the base leaks into the small-diameter portion 20b of the base due to the difficulty of the injection work.
Such poor lighting of the lamp as the adhesive leaks from the base causes a problem such as darkening the image of the projector device, which is a serious problem.
[0004]
In order to solve such a problem, a structure in which a ceramic washer is provided as a partition plate 16 for the adhesive 15 in the base 20 has been proposed. (See JP-A-9-45227)
FIG. 4 shows a structure using such a ceramic washer. That is, a ceramic washer is provided as a partition plate 16 for the adhesive 15 in the base 20, and even if the adhesive 15 is injected into the base by the ceramic washer, the adhesive 15 remains at the tip of the base 20 (lamp sealing). The other side).
[0005]
However, a new problem occurred. It was found that the adhesive that should be stopped by the ceramic washer still leaked to the tip of the die, and sufficient electrical characteristics were not obtained.
[0006]
[Problems to be solved by the invention]
The problem to be solved by the present invention is to provide a power feeding structure for a lamp in which the adhesive injected into the base for fixing to the lamp does not interfere with the power feeding function due to leakage from the base. It is.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the power feeding structure of the lamp of the present invention includes a lead bar extending from the sealing portion of the lamp, a power feed wire connected to the lead bar, and a tip of the power feed twist line exposed. A disk-like partition plate that covers the power supply lead wire and the lead bar and is made of a base fixed to the end of the lamp sealing portion with an adhesive, and has a through hole for the lead bar, The lead bar is joined to the metal winding wire by a ribbon through the through hole of the partition plate, and the partition plate is arranged at a substantially right angle with the lead rod at the position where the lead rod exists inside the base. The adhesive is filled on the lamp side from the partition plate.
[0008]
Furthermore, the power supply structure of the lamp of the present invention is suitable as a power supply structure of a discharge lamp in which mercury is enclosed in an amount of 0.15 mg / cc or more.
[0009]
[Action]
In the power supply structure described in the prior art, the adhesive leaks regardless of using a ceramic washer. As a result of pursuing this cause, it was found that the metal penetrated into the metal wire in the cap by capillary action and reached the tip of the cap.
The invention of the present application is characterized in that a partition plate is provided at the position of the lead bar in order to prevent entry into such a metal wire by capillary action.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an example of a power feeding structure for a lamp according to the present invention. The same reference numerals as those shown in FIGS. 3 and 4 denote the same members.
That is, the adhesive 15 filled in the base 20 is filled on the sealing portion side of the lamp, that is, on the right side in the drawing with respect to the partition plate 16, and the partition plate 16 is on the portion where the metal winding wire 14 does not exist. That is, it is characterized in that it is arranged in the lead bar portion.
That is, the lead rod 12 extending from the lamp sealing portion 10 is joined to the metal winding wire 14 by the white copper ribbon 13 through the through hole of the disk-shaped partition plate 16. Then, the adhesive 15 is filled closer to the lamp sealing portion 10 than the partition plate 16.
As an example, the base 20 is made of nickel-plated brass and has an inner diameter of the large-diameter portion 20a. The inner diameter is 8 mm, the length is 11 mm, the inner diameter of the small diameter portion 20 b is 1.5 mm, and the length is 7 mm. The partition plate 16 is made of a heat-resistant ceramic and has a thickness of 1 mm and a diameter of 7.5 mm. A thermosetting inorganic adhesive is used as the adhesive 15.
[0011]
FIG. 2 shows a discharge lamp and a concave reflecting mirror using the feeding structure of the present invention.
The discharge lamp 1, the concave reflecting mirror 2, and the front glass 3 constitute a light source device. In the figure, a discharge vessel 4 of a short arc type high-pressure mercury discharge lamp 1 is a substantially spherical body made of quartz glass, and a pair of electrodes, that is, an anode 5 and a cathode 6 are arranged opposite to each other inside the discharge vessel 4. Yes. In addition, mercury and a rare gas are sealed inside the discharge vessel 4. And the sealing part 6 is integrally connected by the both ends of the discharge vessel 4 integrally. The sealing part 6 is formed by depressurizing the inside of a fused quartz glass pipe body extending from both ends of the discharge vessel 4, that is, formed by a shrink seal method. A molybdenum foil (not shown) for electrically connecting the electrodes 5, 6 and the external lead 8 is embedded in the portion 6.
Note that the polarity of the direct current lighting type anode 5 and the negative electrode 6 may be opposite to the state shown in FIG. 1, and may be the alternating current lighting type. The sealing portion 12 may be formed by a pinch seal method in which a quartz glass pipe body is melted and crushed.
A base 9 is connected to a sealing portion on the neck side of the concave reflecting mirror 2 in the sealing portion 6. The base 9 has the structure shown in FIG.
[0012]
As a specific numerical example of the short arc type high-pressure mercury lamp 1, the amount of mercury enclosed is 0.20 mg / mm ³ , and argon gas is enclosed as a rare gas at a pressure of 10 KPa. The distance between the electrodes is 1.5 mm, the inner volume of the discharge vessel 11 is 260 mm ³ , the rated voltage is 82V, and the rated power consumption is 200W. Naturally, numerical examples are not limited to these, but in order to use the short arc type high-pressure mercury discharge lamp 1 as a light source lamp for a liquid crystal projector apparatus, it is necessary to enclose mercury in an amount of 0.15 mg / mm ³ or more. There is.
[0013]
The concave reflecting mirror 2 is made of glass, for example, borosilicate glass, and the front opening has an inner diameter of about 120 mm. The reflecting surface 21 of the concave reflecting mirror 2 is a rotating curved surface, and a deposited film such as titania-silica having excellent reflection characteristics is formed on the surface thereof. A support tube 22 is formed on the top of the concave reflecting mirror 20, and one sealing portion 6 of the discharge lamp 10 is inserted into the support tube 22. The discharge lamp 1 is in a state where its axis coincides with the optical axis of the concave reflecting mirror 2 and the arc bright spot formed between the electrodes 5 and 6 at the time of lighting is located at the first focal point of the concave reflecting mirror 2. The concave reflecting mirror 2 is fixed by an adhesive 23 filled in the support cylinder 22.
The front opening of the concave reflecting mirror 20 is covered with a light-transmitting front glass 3 made of, for example, borosilicate glass so that, if the high-pressure mercury lamp 10 is broken, the fragments are not scattered from the front opening. Yes.
[0014]
As described above, according to the power feeding structure of the present invention, the partition plate for the adhesive is provided in the base at the position where the lead bar is present instead of the position where the metal winding line exists. It does not cause troubles in the welding of the metal wire and the base by flowing through the capillary phenomenon.
[Brief description of the drawings]
FIG. 1 shows a power feeding structure of a lamp according to the present invention.
FIG. 2 shows a discharge lamp using the power feeding structure of the present invention.
FIG. 3 shows a conventional lamp feeding structure.
FIG. 4 shows a conventional lamp feeding structure.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Sealing part 11 Metal foil 12 Lead rod 13 White copper ribbon 14 Metal winding wire 15 Adhesive 16 Partition plate 20 Base

Claims (2)

A lead rod extending from the sealing portion of the lamp, a feed wire connected to the lead rod, and a tip of the feed cord is exposed to cover the power feed wire and the lead rod; and In the power feeding structure of the lamp consisting of a base fixed with an adhesive to the end of the sealing part,
Having a disc-shaped partition plate having a through hole for the lead rod;
The lead bar is joined to the metal wire by a ribbon through the through hole of the partition plate,
This partition plate is arranged at a substantially right angle to the lead bar at the position where the lead bar exists in the base.
A power feeding structure for a lamp, wherein an adhesive is filled on the lamp side from the partition plate. The lamp power feeding structure according to claim 1, wherein the lamp power feeding structure is used for a discharge lamp in which mercury of 0.15 mg / mm ³ or more is enclosed.

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