JPH0877973A - Metal halide lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve structure so as to reduce the number of insulating tubes without reducing performance by arranging a pair of band members for binding the both ends of a light emitting tube to a frame so that the light emitting tube is supported on the frame. SOLUTION: In the conventional metal halide lamp, although a light emitting part of a light emitting tube is interposed between facing two portions of a frame requiring insulation, in a metal halide lamp 100, the portion of a frame 70 requiring insulation, adjacent to a light emitting part 61 of a light emitting tube 60 is only a joining part 77. By arranging one insulating tube 55 for insulating the portion of the joining part 77, the insulating condition the same as the case that two insulating tubes are arranged in the conventional metal halide lamp can be obtained. Since first foot parts 71, 73 of the frame 70 of a metal halide lamp 100 are constituted with an integral member, structural strength is increased compared with the frame of the conventional metal halide lamp, and the light emitting tube 60 is more stiffly supported.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal halide lamp, and more particularly to a metal halide lamp having an improved frame structure for supporting an arc tube.

[0002]

2. Description of the Related Art Metal halide lamps are excellent in performance such as brightness and luminous efficiency and are mainly used in places where high brightness is required. A metal halide lamp generally has a structure as shown in FIG.

As shown in FIG. 2, a metal halide lamp 1 is a sealed oval glass case 10 and a cylindrical arc tube 2 located at the center of the glass case 10.
0, and a frame 30 that is fixed by a support member 40 and is inside the case 10.

A pair of electrodes 28 and 29 are fixed to both ends 22 and 23 of the arc tube 20. At the central portion of the arc tube 20, there is provided a light emitting portion 21 that discharges light by causing discharge inside when a predetermined voltage is applied between the electrodes 28 and 29. The frame 30 is located so as to be separated from the one end 23 of the arc tube 20 by a predetermined distance in the longitudinal direction of the arc tube 20. Frame 3
0 is a body portion 35 formed long in a direction intersecting with the longitudinal direction of the arc tube 20, and the arc tube 2 from both ends of the body portion 35.
A pair of leg portions 31 and 32 that extend long along the longitudinal direction of the arc tube 20 are provided on the side of the other end portion 22 of 0 to form a “U” shape as a whole. Legs 3 of the frame 30
1, 32 are located facing both sides of the light emitting portion 21 of the arc tube 20. The arc tube 20 is located between the legs 31, 32 of the frame 30 and the body portion 35, and
The both end portions 22 and 23 supporting 0 are fixed to the leg portions 31 and 32 of the frame 30 by a pair of band members 41 and 42 which further support them.

On the other hand, in order to prevent the frame 30 from being charged when a voltage is applied to the electrodes 28 and 29 of the arc tube 20, an insulating tube 50 is attached to the legs 31 and 32 of the frame 30. Two light emitting parts 21 of the arc tube 20 are fixed so as to be symmetrical along the outer peripheral surface. An expensive quartz tube is mainly used as the insulating tube 50.

If the insulation tubes 50 are not provided on the leg portions 31 and 32 of the frame 30 having the above-mentioned structure, the electrodes 28,
The frame 30 is charged when a voltage is applied to 29. As a result, the negative ions inside the light emitting portion 21 move to the side of the legs 31 and 32 of the frame 30 that faces the light emitting portion 21 and adhere to the inner wall of the case 10 and the legs 31 and 32 of the frame 30. Therefore, the luminous efficiency of the metal halide lamp 1 is reduced.

[0007]

However, as described above, the conventional structure that requires the use of two expensive insulating tubes 50 is excellent in performance such as luminous efficiency and brightness, but
There was a problem that the cost of the metal halide lamp increased.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an insulating tube such as a quartz tube for preventing electrification of an arc tube supporting frame without deteriorating the performance. It is to provide a metal halide lamp with an improved structure so as to reduce the number of the lamps.

[0009]

In order to achieve the above object, the metal halide lamp according to the present invention has a sealed case, a frame fixed to the inside of the case, and a light emitting portion between both ends. And a pair of band members for connecting both ends of the arc tube to the frame so that the arc tube is supported by the frame.

The frame is positioned so as to be separated from one end of the arc tube by a predetermined distance in the longitudinal direction of the arc tube.

The frame is separated from the first body portion elongated in the direction intersecting the longitudinal direction of the arc tube and the other end of the arc tube by a predetermined distance in the longitudinal direction of the arc tube. A second body portion that is located in a long direction in a direction intersecting the longitudinal direction of the arc tube, and a pair of bands extending from both ends of the first body portion toward the second body portion by a predetermined length. A pair of first leg portions to which any one of the band members is coupled, and a pair of first leg portions extending from both ends of the second body portion toward the first body portion by a predetermined length. A pair of second legs to which another one of the band members is coupled, and one of the pair of first legs and one of the pair of second legs are connected to each other. The point is that it does.

According to the present invention, conventionally, two insulating tubes are installed on both sides of the arc tube in the metal halide lamp, and the performance such as luminous efficiency and brightness is not deteriorated.

Further, by forming the frame structure in the body portion at the tip of the lamp with an integral member, the arc tube is firmly supported and the reliability of the product is improved.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

Referring to FIG. 1, a metal halide lamp 100 according to the present invention has a sealed oval glass case 9.
0 and a cylindrical arc tube 60 located at the center of the glass case 90. Both ends 6 of this arc tube 60
A pair of electrodes 68 and 69 are fixed to the electrodes 2 and 63.
A light emitting unit 61 is provided at the center of the light emitting tube 60 to radiate light when a predetermined voltage is applied to the electrodes 68 and 69 to discharge the light.

The metal halide lamp 100 includes a frame 70 fixed in a case 90 by a support member 80,
A pair of band members 81 and 82 for fixing the arc tube 60 to the frame 70 are provided.

The frame 70 includes a first body portion 78, a second body portion 79, first leg portions 71 and 73, and a second leg portion 7.
2, 74, and the first leg portions 71, 73
Are integrally formed via the first body portion.

The first body portion 78 is located at a predetermined distance from one end 62 of the arc tube 60 in the longitudinal direction of the arc tube 60, and extends in a direction intersecting with the longitudinal direction of the arc tube 60. Is formed long. Then, the second body portion 79 extends from the other end 63 of the arc tube 60 to the arc tube 60.
Are arranged so as to be separated from each other by a predetermined distance in the longitudinal direction, and are formed long in a direction intersecting with the longitudinal direction of the arc tube 60.

The first leg portions 71 and 73 are the first body portion 78.
A predetermined length from both ends toward the second body portion 79 (a length that does not reach the range facing the light emitting portion 61 of the light emitting tube 60)
Is formed by extending the first leg portion 71,
One end 62 of the arc tube 60 is coupled to 73 by a band member 81. The second leg portions 72 and 74 are formed to extend from both ends of the second body portion 79 toward the first body portion 78 to a predetermined length (a length that does not reach a range facing the light emitting portion 61 of the arc tube 60). The other end 63 of the arc tube 60 is connected to the second legs 72 and 74 by a band member 82.

The leg portion 73, which is one of the first leg portions, and the leg portion 74, which is one of the second leg portions, are connected to each other by a connecting portion 77. The connecting portion 77 may be formed of another member by welding both ends thereof to the first leg portion 73 and the second leg portion 74, respectively, but the first leg portion 73 or the second leg portion 74 may be used. Of these, it is preferable that an end portion obtained by extending one of the legs is welded to the second leg 74 or the first leg 73.

As shown in FIG. 1, the frame 70 has a "C" shape as a whole and surrounds the arc tube 60. Therefore, in the frame 70, the connecting part 71 is the only part facing the light emitting part 61 of the arc tube 60. In order to prevent the frame 60 from being charged, one insulating tube 50 is fitted into the connecting portion 77 and fixed at a position facing the light emitting portion 61 of the light emitting tube 60.

The basic function of the metal halide lamp 100 according to the present invention thus constructed is similar to the basic function of the conventional metal halide lamp 1 described with reference to FIG.

However, in the conventional metal halide lamp 1, there are two parts of the frame 30 that require insulation and that face each other with the light emitting part 21 of the arc tube 20 interposed therebetween.
Although it was a place, the metal halide lamp 100 of the present invention
Then, the portion of the frame 70 adjacent to the light emitting portion 61 of the light emitting tube 60 and requiring insulation is only the connecting portion 77. Therefore, by providing one insulating tube 55 that insulates the portion of the connecting portion 77, it is possible to achieve the same insulating state as when the two insulating tubes 50 are provided in the conventional metal halide lamp.

Further, since the first leg portions 71, 73 of the frame 70 of the metal halide lamp 100 according to the present invention are made of an integral member, the structural strength is improved as compared with the frame 30 of the metal halide lamp having the conventional structure. Then, the arc tube 60 is supported more firmly.

[0025]

As described above, in the metal halide lamp according to the present invention, the structural strength of the frame is increased because the first leg of the frame supporting the arc tube is an integral member. Improves reliability. Further, since the number of insulating tubes for insulating the frame is reduced by the improvement of the frame structure, it is possible to reduce the cost of parts and the assembly work.

[Brief description of drawings]

FIG. 1 is a schematic front view of a metal halide lamp according to the present invention.

FIG. 2 is a schematic front view of a conventional metal halide lamp.

[Explanation of symbols]

 60 arc tube 61 light emitting part 68,69 electrode 70 frame 71,73 first leg part 72,74 second leg part 78 first body part 79 second body part 80 support member 81,82 band member 90 glass case 100 metal halide lamp

Claims (2)

[Claims] 1. A hermetically sealed case, a frame fixed inside the case, an arc tube having a light emitting part in the center, and both ends of the arc tube so that the arc tube is supported by the frame. In a metal halide lamp comprising a pair of band members coupled to a frame, the frame is positioned so as to be separated from one end of the arc tube by a predetermined distance in the longitudinal direction of the arc tube, and the longitudinal direction of the arc tube. A first body portion elongated in a direction intersecting with the arc tube, and a direction extending from the other end of the arc tube in the longitudinal direction of the arc tube by a predetermined distance and intersecting the longitudinal direction of the arc tube. A second body portion that is formed to be long, and one band member of the pair of band members that is extended from both ends of the first body portion toward the second body portion by a predetermined length. A pair of A leg portion, and a pair of second leg portions extending from the both ends of the second body portion toward the first body portion by a predetermined length and to which another one of the pair of band members is coupled. And a metal halide lamp, wherein any one of the pair of first leg portions and any one of the pair of second leg portions are connected to each other. 2. The metal halide according to claim 1, wherein any one of the pair of first leg portions and any one of the pair of second leg portions are connected to each other by welding. lamp.