JPH0573855U - Double tube incandescent light bulb - Google Patents

Abstract

(57) [Summary] [Objective] To provide a double-tube incandescent light bulb which is easy to assemble and has high mass productivity, requires a small number of members, and has a short distance from the base to the inner bulb. [Composition] An inner bulb having a light emitting filament disposed inside, and having a pair of inner conducting wires connected to the light emitting filament and extending outward from a pinch seal portion at one end,
In a double-tube incandescent light bulb that consists of an outer bulb that covers this inner bulb, and a pair of outer conductors connected to the inner conductor is extended outward by being held by the stem portion of the outer valve, the outer conductor is And the dumet wire and the lead wire are connected in a straight line, the charcoal wire is connected to the inner conductor wire by butt welding, and a part of the charcoal wire is embedded in the stem portion.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a double-tube incandescent light bulb used for studio lighting, store lighting, and temporary lighting at construction sites.

[0002]

[Prior Art]

 Double-tube incandescent light bulbs, in which the inner bulb with the luminous filament inside is covered by the outer bulb, are widely used for studio lighting, store lighting, and temporary lighting at construction sites.

A conventional internal structure of such a double-tube incandescent light bulb will be described with reference to FIG. 2. A light emitting filament (not shown) is arranged in the inner bulb 1, and a pair of inner conductors 2 are provided with a pinch seal portion 11. Growing from. The outer lead wire 6 is held by the stem portion 41 of the outer valve 4 that covers the inner valve 1 and electrically connected to the inner conductor wire 2. At least one of the outer lead wire 6 has a fuse at the end thereof. Separate wire rods are welded to form bent portions 61 and 62, and the ends of the bent portions 61 and 62 are connected to the inner conductor 2. An extended portion 63 at the tip of one of the outer lead wires 6 is welded to the metal sleeve 7 wound around the pinch seal portion 11 to hold the inner valve 1. An exhaust hole 42 is provided in the stem portion 41, and a screw-in base 5 is attached to the lower end of the outer valve 4.

[0004]

[Problems to be solved by the device]

 As described above, the conventional double-tube incandescent light bulb has a complicated structure for holding the inner bulb on the outer bulb, and there is a problem that the assembly process requires labor. That is, it takes a lot of time to wind the metal sleeve around the pinch seal part of the inner valve, and it takes time to weld the metal sleeve and the external lead wire to attach the fuse, resulting in lack of mass productivity. .. There is also a problem that many members are required and the distance from the mouthpiece to the inner valve becomes large.

The present invention has been made to solve the above problems, and its purpose is to easily assemble and mass-produce, and to reduce the number of required members. The objective is to provide a double-tube incandescent light bulb that shortens the distance from the inner bulb to the inner bulb.

[0006]

[Means for Solving the Problems]

 In order to achieve such an object, the present invention provides an inner bulb having a pair of inner conductive wires, which is provided with a light emitting filament inside and which is connected to the light emitting filament and extends outward from a pinch seal portion at one end. In a double-tube incandescent light bulb that consists of an outer bulb that covers the inner bulb, and a pair of outer conductors that are connected to the inner conductor and are extended outward by being held by the stem of the outer bulb, connect the outer conductor to the charcoal wire. It is constructed by connecting the dumet wire and the lead wire in a straight line. The charcoal wire is connected to the inner conductor wire by butt welding, and part of the charcoal wire is embedded in the stem part. Further, it is preferable that at least one of the lead wires of the outer conductive wire is made of a thin copper-nickel alloy wire and also serves as a fuse.

[0007]

[Action]

 Part of the charcoal wire that forms the outer conductor is embedded in the stem of the outer valve, and this charcoal wire that protrudes from the stem into the outer valve is connected by butt welding to the inner conductor that protrudes from the pinch seal of the inner valve. Therefore, the inner valve can be held accurately and easily, and the distance from the base to the inner valve can be shortened. Moreover, there is an advantage that the number of parts is small because no metal sleeve is required.

[0008]

【Example】

 The present invention will be described in detail below with reference to the embodiments shown in the drawings. In FIG. 1, a quartz glass inner bulb 1 in which a light emitting filament (not shown) is disposed is a 110V, 60W halogen incandescent bulb, and a pinch seal portion 11 is formed at one end thereof. A pair of inner conductors 2 made of molybdenum having a diameter of 0.7 mm extend from the pinch seal portion 11.

The outer bulb 4 that covers the inner bulb 1 is made of soda glass, and a bantam stem type stem portion 41 made of soda glass or lead glass is integrally provided below the outer bulb 4. Further, an exhaust hole 42 is formed in the stem portion 41. A screw-in type base 5 is attached to the lower end of the outer valve 4.

The outer conducting wire 3 is composed of a charcoal wire 31, a dumet wire 32, a lead wire 33 or a lead wire 34, which are connected in a straight line by butt welding. Here, the charcoal wire 31 is an Fe wire plated with Ni and has an outer diameter of 0.8 mmφ. The Dumet wire 32 is an Fe-Ni wire coated with a Cu pipe and has an outer diameter of 0.4 mmφ. Also, one of the lead wires 33 is made of a Ni-Cu alloy wire having an outer diameter of 0.2 mmφ and also serves as a fuse. Therefore, the fuse wire can be attached very easily as compared with the conventional example shown in FIG. The other lead wire 34 is a stranded wire of Cu having an outer diameter of 0.5 mmφ.

Of the outer conducting wire 3, a part of the charcoal wire 31 and almost all of the dumet wire 32 are embedded and held in the stem portion 41. The length of the charcoal wire 31 extending from the stem portion 41 is 5 mm, and the length of the charcoal wire 31 embedded in the stem portion 41 is 5 mm. The tip of the charcoal wire 31 extends into the outer valve 4, and the lead wire 33 and the lead wire 34 extend outside the outer valve 4. That is, the outer conductor 3 penetrates the stem portion 41. The tip ends of the lead wire 33 and the lead wire 34 are connected to each other at predetermined positions of the base 5 by brazing so as to be insulated from each other. The tips of the pair of charcoal wires 31 and the inner conductor 2 are welded by butt welding at the welded portion 21.

Next, a manufacturing process of such a double-tube incandescent light bulb will be described. [Step 1] The three wires of the charcoal wire 31, the dumet wire 32, and the lead wire 33 or the lead wire 34 are connected in a straight line by butt welding, and a pair of outer conductor wires 3 are manufactured in advance. [Step 2] The charcoal wire 31 of the outer conductor 3 is connected to the pair of inner conductors 2 protruding from the pinch seal portion 11 of the inner valve 1 by butt welding. [Step 3] The outer conductor 3 is made to penetrate the stem portion 41 in an airtight manner. At this time, the charcoal wire 31 is projected from the stem portion 41, and part of it is embedded in the stem portion 41. The dumet wire 32 is almost entirely buried, and airtightness is achieved at the portion of the dumet wire 32. [Step 4] The stem portion 41 is welded to the outer valve 4, and the inside of the outer valve 4 is exhausted through an exhaust pipe (not shown) connected to the exhaust hole 42 of the stem portion 41 and nitrogen gas is injected and exhausted. Seal the tube. Then, the ends of the lead wire 33 and the lead wire 34 are brazed to predetermined positions of the base 5, and the base 5 is fixed to the lower end of the outer valve 4 with an adhesive to complete the process.

Thus, in the double-tube incandescent lamp of the present invention, the outer conductor 3 including the charcoal wire 31, the dumet wire 32, and the lead wire 33 or the lead wire 34 is manufactured in advance, and the pinch seal portion 11 of the inner bulb 1 is formed. Since the charcoal wire 31 of the outer conductor wire 3 is connected by butt welding to the pair of inner conductor wires 2 protruding further, and a part of the charcoal wire 31 is embedded in the stem portion 41, the holding strength of the inner valve 1 is sufficiently secured. Moreover, the holding structure is extremely simple and can be held accurately. Since the mounting structure is simple, the distance between the base 5 and the inner bulb 1 can be shortened, and the lamp can be downsized. Further, since the lead wire 33 is a thin nickel-copper alloy wire, this lead wire 33 also serves as a fuse, and there is an advantage that a new fuse mounting mechanism is unnecessary.

[0015]

[Effect of the device]

 As described above, according to the present invention, the number of members required is small, the inner valve can be accurately and reliably held with a simple structure, and the assembling process is easy and mass productivity is improved. It is rich, and the distance from the base to the inner bulb is short, making it possible to make a double-tube incandescent light bulb that can be downsized.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 1 Inner valve 11 Pinch seal part 2 Inner conducting wire 21 Welding part 3 Outer conducting wire 31 Charcoal wire 32 Dumet wire 33, 34 Lead wire 4 Outer valve 41 Stem part 5 Base

Claims (2)

[Scope of utility model registration request] 1. An inner bulb having a pair of inner conductors, wherein a light emitting filament is disposed inside, and which is connected to the light emitting filament and extends outward from a pinch seal portion at one end, and an outer bulb covering the inner bulb. In the double-tube incandescent light bulb in which a pair of outer conductors connected to the inner conductor is held by the stem portion of the outer bulb and extends outward, the outer conductors are charcoal wire, dumet wire, and lead wire. Are connected linearly, the charcoal wire is connected to the inner conductor wire by butt welding, and a part of the charcoal wire is embedded in the stem portion. light bulb. 2. The double-tube incandescent light bulb according to claim 1, wherein at least one of the lead wires of the outer conductive wire is made of a thin copper-nickel alloy wire and also serves as a fuse.