JP2792933B2 - Incandescent light bulb - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an incandescent lamp using a metal foil as an intermediate conductor for electric input embedded in a hermetically sealed portion, and particularly to a halogen lamp.

[Prior art and its problems] A halogen bulb having a structure in which a connecting portion is formed by extending a wire constituting a filament wire, the connecting portion is welded to a metal foil, and the metal foil is embedded in a hermetically sealed portion. Has been known since the General Electric Company of the United States was commercialized in the 1955s.

In general, most of the constituent materials of this halogen bulb, even today, are made of quartz for bubble glass, tungsten for filament wire, molybdenum for metal foil, and molybdenum or tungsten for the outer conductor, and are buried in the hermetically sealed part. The structure as an intermediate conductor for electric input can be roughly classified as follows.

(B) A central part of a round bar made of molybdenum or the like as an intermediate conductor is press-formed and processed, and an inner conductor, a metal foil, and an outer conductor are integrated. There is an advantage that there is no assembly work by welding.

(B) An assembly obtained by welding an inner conductor and an integrated metal foil and outer conductor.

(C) An inner conductor, a metal foil, and an outer conductor, which are sequentially assembled by welding.

(D) In (b) and (c) above, the inner conductor is formed by extending the filament wire.

In the above structure, except for (a), a welding operation is performed somewhere. This operation naturally has advantages and disadvantages, and many improved inventions have been made to improve the defects.

For example, for the connection work between a metal foil and an outer conductor, an excellent invention is disclosed in Japanese Patent Publication No. Sho 63-40354 (title of invention "Structure of Conductor in Tube Sealing Part").
53-13251 (name of the invention "Structure of the conductor in the sealed portion of the tube") also discloses an excellent invention. The point of these inventions is to use the convex portion of the outer conductor or to form the convex portion of the outer conductor when connecting the two. It has gained.

However, since the outer conductor is generally a thick and independent part, it is easy to form a convex portion. Therefore, although the above-described invention has resulted in a path, as described above, the connection operation is performed by the inner conductor. In particular, when the inner conductor is formed by extending the filament wire, it is generally thin, even if it is thick, because it is integrated with the filament. It is difficult to form a convex part on the molded connection part. Very inconvenient to handle. Therefore, when connecting a thick inner conductor or an outer conductor to a metal foil as an independent part, the above-described invention can be used, but the filament wire is extended to form a connection part and connected to the metal foil. It is difficult to use the above-described invention for the connection work in the incandescent lamp having the configuration. Therefore, there are many failure accidents, such as a welding failure accident and a burning failure of a metal foil, as compared with the connection using the convex part.

(Object of the present invention)

An object of the present invention is to provide an incandescent lamp having a structure in which a connecting portion is formed by extending a wire constituting a filament wire, the connecting portion is welded to a metal foil, and the metal foil is embedded in a hermetically sealed portion. An object of the present invention is to provide a connector with reduced connection failure at the connection portion.

[Means for achieving the purpose]

An incandescent lamp having a structure in which a connecting portion is formed by extending a wire constituting a filament wire, the connecting portion is welded to a metal foil, and the metal foil is embedded in a hermetically sealed portion. The foil is sandwiched between the hard sphere and the cushion material and pressed to form a convex portion, and the convex portion and the connection portion are
Welding is performed via a brazing material such as platinum.

By the way, the thickness of the metal foil depends on the current of the bulb,
0.02 mm to 0.04 mm in many cases, in order to form a good convex part of a certain shape on such a thin foil, a metal foil is sandwiched between a hard sphere and a cushion material and pressed, and a spherical surface is formed on the metal foil. The method of forming the convex part in the shape of a circle is optimal.

[Action]

Since the brazing material such as platinum is welded to the convex portion on the metal foil side where the position and area are determined, the welding conditions are constant, and therefore, the brazing material fixed firmly to the metal foil corresponds to the convex portion. At the position where the filament wire is formed, a generally thin wire-like connecting portion, which is an extension of the filament constituting the filament wire, is welded. Thus, here also, the welding conditions are constant and a firm welding can be performed.

In addition, the shape of the convex portion is constant because the metal foil is pressed between the hard sphere and the cushion material and pressed.

〔Example〕

FIG. 1 is a schematic explanatory view of a halogen bulb adopting the present invention, wherein 1 is a quartz bulb, 2 is a press seal portion, 3 is a tungsten filament coil, and 4 is a connection formed by extending the coil. Reference numeral 5 indicates molybdenum metal foil, 6 indicates an external lead rod, and 7 indicates a platinum foil as a brazing material.

FIG. 2 is an enlarged cross-sectional view of the welding structure in the molybdenum metal foil 5, and the dimensions depend on the power consumption and current used of the halogen bulb, but the external lead rod is 0.8 mm in diameter and 2 mm in length.
A 0 mm molybdenum round bar, platinum foil 7 has a thickness of 0.03 mm, an area of 1 mm x 2 mm, and a molybdenum metal foil 5 has a thickness of 0.028 mm.
Width 3mm, length 8.5mm, diameter of coil wire is 0.13mm ~ 0.4m
m and the diameter of the connection formed by extending it is 0.1
3 mm to 0.4 mm.

The convex portion 8 has a diameter of 0.2 mm and a depth of 0.015 mm to 0.03 mm when described in terms of the size and shape of the recess formed on the opposite side.
It is.

FIG. 3 is an explanatory view of a method of forming the extremely small recess, wherein 9 is a hard ball, for example, a ball of a bearing,
Reference numeral 10 denotes a mounting bracket for the hard ball 9, and reference numeral 11 denotes a cushion material, for example, silicone rubber. When the molybdenum metal foil is sandwiched between these and pressed, a recess having a constant size and shape can be easily obtained. At first, I tried to make it by pressing a needle-shaped tool against molybdenum metal foil.
It was relatively large, such as 0.1 mm, the shape was not constant, and the foil sometimes broke. Therefore, the welding conditions of the platinum foil to the projections were not constant, and the accident of burning, detachment, etc. of the welds occurred, but when the projections were formed by the above-described method, it was small,
This is convenient because the dimensions and shape are constant.

By the way, if the method of manufacturing the intermediate conductor for electric input using the above metal foil is described again, as described above, since the shape and size of the convex portion of the metal foil are constant, in the operation of welding the platinum foil, It is easy to keep welding conditions constant, so that there is no spark accident or other defect during welding. As described above, in the present invention, the connection strength is remarkably large and the number of defects is small. In this way, the connection portion of the filament wire is welded to the platinum foil firmly fixed to the metal foil at a position corresponding to the convex portion of the metal foil, so that the welding conditions are stable and strong. Connection is possible. As a result, in the connection structure between the metal foil and the filament wire, it is possible to provide a halogen bulb free from accidental welding.

By the way, in the above-described embodiment, an example in which two convex portions are provided is shown, but the present invention is not limited to this, and even if one convex portion is sufficient for the purpose depending on the size of the metal foil. And conversely, three or more locations may be provided.

In the case where the protrusions are formed at the two places shown in the figure, the metal foil has a good “seat”, the workability is improved, and the connection strength is large, as compared with the case of the protrusion formed by the needle-shaped tool. Eight times the strength was obtained.

(Effect of the present invention)

As can be understood from the description of the above embodiment, the present invention uses a metal foil as an intermediate conductor for electric input buried in a hermetically sealed portion, and extends the filament wire of the filament wire to the metal foil. In the incandescent lamp having a configuration in which the connecting portions formed as described above are connected via a brazing material, not only an incandescent lamp that does not have an accident of welding failure at the connection portion can be provided, but also a condition of the welding operation in the bulb manufacturing process. Advantages such as improved yield and stable quality due to stability can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a halogen lamp, FIG. 2 is an enlarged sectional view of a welding structure, and FIG. 3 is an explanatory view of a method of forming a recess. In the figure, 1 is a quartz bulb, 2 is a press seal part, 3
Is a tungsten filament coil, 4 is a connecting portion, 5 is a molybdenum metal foil, 6 is an external lead rod, 7 is a platinum foil, 8
Indicates a convex portion, 9 indicates a hard ball, 10 indicates a hard ball mounting bracket, and 11 indicates a cushion material.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Sho 56-107664 (JP, U) Japanese Utility Model Sho 52-86293 (JP, U) Japanese Patent Publication No. Sho 63-40354 (JP, B2) (58) Field (Int.Cl. ⁶ , DB name) H01K 1 / 38,3 / 20

Claims (1)

(57) [Claims] An incandescent lamp having a structure in which a connecting portion is formed by extending a wire constituting a filament wire, the connecting portion is welded to a metal foil, and the metal foil is embedded in a hermetically sealed portion. The metal foil is sandwiched between a hard ball and a cushion material and pressed to form a convex portion, and the convex portion and the connection portion are welded to each other via a brazing material such as platinum. And incandescent bulb.