JPH02262231A - Single seal type metal vapor discharge lamp - Google Patents

Abstract

PURPOSE:To prevent the displacement of an arc center, stabilize the luminescent characteristic, and extend the life by arranging and connecting a pair of electrode shaft sections to side faces of respective metal foil conductors on opposite sides to each other. CONSTITUTION:One electrode shaft section 4 is welded to one face of one metal foil conductor 6, the other electrode shaft section 4 is welded to the other face of the other metal foil conductor 6. The electrode shaft sections 4 and 4 are inclined in opposite directions to each other. Even if electrode coil sections 5 and 5 are displaced, they are faced to the bulb center at symmetrical positions, and the arc center nearly coincides with the bulb center. Detective sealing is reduced, yield is improved, and the luminescent characteristic is stabilized. The arc is not moved near the bulb wall eccentrically, a bulb 1 is not locally heated, and the life is extended.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object 1] (Industrial Application Field) The present invention relates to a single-sealed metal vapor discharge lamp that is applied to small metal halide lamps and the like.

(Prior art) High-intensity discharge lamps, that is, high-pressure metal vapor discharge lamps (HID), which were traditionally used for outdoor lighting and factory lighting, are now increasingly being used for low-input indoor lighting such as stores. It's here.

The reason why lamps came to be used in stores, etc. was that arc tubes were made smaller, and along with this, the outer tube of the lamp was changed from hard glass to quartz, which has higher heat resistance, and the external shape was also made smaller and more compact. In addition to this, the conventional characteristics of high efficiency, high color rendering, high output, and long life can be utilized, so it is possible to save power by using it in place of incandescent light bulbs and 10-gen light bulbs. There are reasons.

In particular, metal halide lamps are becoming more popular because they are superior to other discharge lamps in terms of high efficiency and color rendering, and are extremely suitable for illuminating displayed products.

By the way, in order to miniaturize the arc tube, if we use a conventional valve structure with both ends sealed, it not only takes time and effort to mold, but also the sealing part becomes large, resulting in a large shape. There are disadvantages such as increased heat loss from the arc tube through the arc tube.

For this reason, in this type of small lamp, the arc tube shape is a) single-sealed type, in which a crushed seal is formed at only one end of the bulb, and a pair of electrodes are sealed to the crushed and heavy end. It uses a light structure.

In this way, since there is only one sealing part, the loss of 1 µ of heat is smaller than that of a bulb with both ends sealed, which makes it possible to improve luminous efficiency and eliminates the need for molding. Moreover, since there is only one sealing part, which tends to be relatively large in shape compared to the size of the discharge space, there is an advantage that the whole can be made smaller.

(Three problems to be solved by the invention) By the way, in such a piece = 1 stop type light tube, a pair of metal foil conductors are sealed to the crushing sealing part, and an electrode shaft part is attached to each of these metal foil conductors. These electrode shaft portions are connected to each other and guided into the discharge space, and electrode coil portions are provided at the tips of these electrode shaft portions so as to face each other.

In a lamp with such a structure, electrode shaft parts are welded to the side surfaces of the metal foil conductor, and when the sealing part is crushed and sealed, it is pressed in the direction of arrow A in Fig. 3. Since the electrode shaft is pushed through the metal foil conductor, a phenomenon in which the electrode shaft tilts as shown by the imaginary line in FIG. 3 is observed.

In this case, if the electrode shafts are joined to the surfaces of the respective metal foil conductors in the same direction, the direction of inclination of the picture electrode shafts will be the same, so the position of the electrode coil will deviate from the center of the bulb. It ends up.

For this reason, the center of the arc during lighting deviates from the center of the bulb, making the light emission characteristics unstable, and the wall of the bulb near which the arc approaches is excessively heated, resulting in problems such as a shortened lifespan.

The present invention was made under these circumstances, and it prevents the arc center from becoming one position, stabilizes the light emission characteristics, and
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[Structure of the Invention] (Means for Solving the Problems) In the present invention, a pair of electrode shaft portions are arranged and connected to the side surfaces of each metal foil conductor so that they are opposite to each other. It is characterized by

(Function) According to the present invention, even if the respective electrode shaft portions are tilted, they are tilted in opposite directions, so that the electrode coil portions at the tips are positioned symmetrically to each other, preventing the center of the arc from being tilted. . Therefore, the light emitting characteristics are stabilized and the life span is extended.

(Example) The present invention will be described below based on an example shown in the drawings.

The drawing shows an arc tube of a metal halide lamp with a lamp power of 150 W. In the drawing, reference numeral 1 indicates an arc tube bulb made of quartz glass, which is formed into a substantially elliptical spherical shape with an internal volume of 0.5 cc. In such an elliptical spherical valve l, the long axis direction is the valve axis, and a flat crushing sealing part 2 is formed at one end in a direction perpendicular to the valve axis.

A pair of electrodes 3.3 are arranged inside the bulb 1, spaced apart from each other in the axial direction of the bulb, and both of these electrodes 3.3 are sealed to the crushing sealing portion 2 on one side.

The electrode 3.3 is composed of an electrode shaft part 4 and an electrode coil part 5. For example, the electrode shaft part 4 is made of pure rhenium wire with a wire diameter of 0451111, and the electrode coil part 5 is made of a thoriated rhenium wire with a wire diameter of 0.5+u. It is made of tungsten wire and is wound three to four times around the bent tip of the electrode shaft section 4.

These electrode coil portions 5.5 are opposed to each other at a distance of about 61111 mm along the valve axis direction.

The electrode shaft portions 4.4 are respectively connected to metal foil conductors 6.6, such as Mo or the like, sealed to the crushing seal portion 2.

In this case, each electrode shaft part 4, 4, as shown in FIG.
The metal foil conductors 6, 6 are arranged so that their surfaces are opposite to each other.

That is, one electrode shaft portion 4 is welded to one surface of one metal foil conductor 6, while the other electrode shaft portion 4 is welded to the other surface of the other metal foil conductor 6. It is something.

These metal foil conductors 0 and 6 are connected to external lead wires 7 and 7, respectively.
It is connected to the.

In addition, in the valve l, there is a starting rare gas, a predetermined amount of mercury, and 5n12, Nal, Tp I, and lnl.

Metal halides such as NaBr and LiBr are sealed.

In addition, in such single-sealed optical metal halide lamps, the lamp current during stable operation! is 18A, and the lamp power W at this time is set to be 150W. The inner surface area S of the arc tube is approximately 3.5 cm, and the lamp load per unit surface area of the arc tube is approximately 43 W.
It has become aj.

The operation of the embodiment with such a configuration will be explained.

When forming the crushing sealing part 2 at the end of the bulb l, the metal foil conductors G, 0 to which the electrodes 3, 3 and the external lead wires 7, 7 are connected in advance are inserted into the opening of the bulb that is still open. The valve opening wall is heated with a burner or the like to soften it. Next, the softened bulb wall is crushed as shown by arrows A and A in FIG. 3 using pinchers (not shown), thereby closing the opening and sealing the metal foil conductors 7, 7 at the same time.

In this case, the metal foil conductors 7.7 are sandwiched between the glasses, and there is a tendency for the electrode shaft portion 4 bonded to one side of the metal foil conductors 7.7 to be tilted in the direction shown by the imaginary line.

In this embodiment, one electrode shaft portion 4 is connected to one metal foil conductor 6.
7 on one side and 7 on the other side.
Since the polar shaft portion 4 is welded to the other surface of the other metal foil conductor 6, the inclination directions of these electrode shaft portions 4.4 are opposite to each other.

Therefore, even if the electrode coil portions 5.5 are displaced, they will face each other in a symmetrical position with respect to the center of the bulb, so that the center of the arc will substantially coincide with the center of the bulb.

This reduces sealing defects, improves yield, stabilizes the light emitting characteristics, and since the arc does not approach the bulb wall unevenly, the bulb 1 is not locally heated and has a long service life. become.

It should be noted that the present invention is not limited to metal halide lamps, but may be any discharge lamp in which a crushed seal is formed only at one end of the bulb; therefore, it is applicable to other small metal vapor discharge lamps such as high-pressure mercury lamps, etc. It may be.

[Effects of the Invention] As explained above, according to the present invention, since the inclinations of the electrode shaft portions are staggered, sealing defects are reduced, yield is improved, and the light emitting characteristics are stabilized and the lifespan is extended. .

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a cross-sectional view of a small metal halide lamp, FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG. 1, and FIG. It is a sectional view of a line. l... Arc tube bulb, 2... Crushing sealing part, 3...
Electrode, 4... Electrode shaft part, 5... Electrode coil part, 6...
...Metal foil conductor, 7...External lead wire. Portion 1 Applicant's agent Patent attorney Takehiko Suzue Figure 3

Claims (1)

[Claims] A crushed sealing portion is formed at one end of the arc tube, a pair of metal foil conductors is sealed to this crushing sealing portion, an electrode shaft portion is connected to these metal foil conductors, and these electrodes are In a single-sealed metal vapor discharge lamp in which an electrode coil portion is provided at the tip of the shaft portion and these electrode coil portions are opposed to each other in the discharge space, the electrode shaft portion is attached to the side surface of each metal foil conductor. A single-sealed metal vapor discharge lamp characterized in that the lamps are arranged and connected so that the opposite sides are connected.