JPH02295060A - Manufacture of tubular bulb - Google Patents

Abstract

PURPOSE:To simplify the manufacturing processes of a tubular bulb by carrying out sealing process using a gas mixture of an element having higher specific gravity than air and an element having lower specific gravity than air in O- group elements. CONSTITUTION:Sealing is carried out using a gas mixture of an element having higher specific gravity than air and an element having lower specific gravity than air among O-group elements. Since the gas mixture 6 which is led to a glass tube 2 through a gas discharging pipe 2a contains a heavier gas 6a and a lighter gas 6b, the heavier gas 6a flows to descending direction and the lighter gas 6b flows to ascending direction when the gas mixture comes to glass tube 2, and then a gas in the whole tube is replaced with the gas mixture. Due to inactivity of O-group elements, a filament 3, a molybdenum foil 4, and a leading wire 5 are neither oxidized by heating with a burner 10 for sealing nor formed into compounds and thus a process for vacuum heating as posttreatment is not needed.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a method of manufacturing a bulb such as a halogen lamp.

[Conventional technology]

3 and 4 show the conventional manufacturing method of this kind of tube 31 in the order of steps. First, as shown in FIG.
4. Hold the tube to which the lead-in wire 35 is connected, and heat the lower end of the glass tube 32 with the burner 10 to soften it. At this time, the filament 33, the molybdenum foil 34, and the lead-in wire are heated as described above. In order to prevent metal members such as 35 from being oxidized, nitrogen (N 2 ) and hydrogen (H
2) A single or mixed gas 36 such as argon (Ar) is introduced and heating is performed in this atmosphere. After the glass tube 32 has been softened, a pinch seal is performed in which the softened portion is pinched and pressurized with a mold, as shown in FIG. By performing this step, the sealing process of the tube 31 is completed.

[Problem to be solved by the invention]

However, in the conventional sealing process described above, depending on the type of gas 36 used, (1) Hydrogen gas (2) Because it is reducing, the solica in the glass tube 32 tends to sublimate, causing the glass tube 32 to become cloudy. This will adversely affect the characteristics. Further, the above-mentioned silica has a high melting point and is strongly bonded to the glass tube 32, so it is difficult to remove. @Hydrogen gas is adsorbed by glass or metal, or combines with metal, which adversely affects the lifespan of the tube 31, so a vacuum heat treatment process is required after the sealing process, but this process is added. However, it is difficult to completely eliminate the hydrogen gas. ○ Metal part reacts with oxygen in the moon to form water (H20). During this reaction, a small explosion occurs on the surface of the metal member, which causes unevenness on the surface of the metal member and deteriorates characteristics such as life. (2) The water (H20) generated above oxidizes the metal again and deteriorates its properties such as life. ■Nitrogen gas■ Due to the heat of the sealing process, it reacts with the above-mentioned metal members to form metal nitrides and deteriorate their characteristics. Since the crow is temporarily adsorbed to a metal member and emitted again, if the tube 31 is a discharge lamp, the discharge characteristics will be extremely deteriorated. For this reason, it is necessary to add a vacuum heat treatment step after the final step. ■Argon gas■ Since the specific gravity is heavier than air, it is difficult to fill the glass tube 32, and during the sealing process, oxidation occurs in the metal parts located on both sides. However, no matter which gas 36 is selected, there are problems such as loss of characteristics or complication of the process by requiring additional steps, so it is necessary to develop a sealing process that does not cause these problems. has become an issue.

[Means to solve the problem]

As a specific means for solving the above-mentioned conventional problems, the present invention provides a method for manufacturing a tube in which a gas is introduced into the tube, and a sealing process is performed by heating in this gas atmosphere.
By providing a method for manufacturing a tube, characterized in that the sealing step is performed using a gas that is a mixture of an element that is a group element and has a heavier specific gravity than air, and an element that is lighter than air, the above-mentioned conventional method can be improved. It is something that solves problems.

【Example】

Next, the present invention will be explained in detail based on an embodiment shown in the drawings. In Fig. 1, reference numeral 1 indicates a tube such as a halogen light bulb in the sealing process, and in this process, a filament 3, molybdenum foil 4, lead-in wire 5, etc. are connected to the glass tube 2. This is similar to the conventional example in that the object is held and one end of the glass tube 2, for example, the lower end side, is heated and softened with a burner 10 and pinch-sealed. The gas 6 introduced into the tube 2 to replace air is 0.
A gas 6 (hereinafter referred to as a mixed gas 6) is a mixture of a gas 6a (hereinafter referred to as heavy gas 6a) and a gas 6b (hereinafter referred to as light gas 6b) with a lighter specific gravity, which are group elements and have a heavier specific gravity than air. ). Specifically, the heavy gas 6a1, that is, a gas having a specific gravity heavier than air, includes argon (Ar), Kl'
)N xenon (Xe), and as light gas 6b with a specific gravity lighter than air, helium (He) is selected.
, neon (Ne). Next, the effects of the sealing process of the present invention explained above will be explained. The mixed gas 6 that is introduced into the glass tube 2 from the exhaust pipe 2a contains heavy gas 6a and light gas 6b. This means that when the heavy gas 6a passes through the exhaust pipe 2a and reaches the inside of the glass tube 2, the heavy gas 6a flows down and the other light gas 6b flows up. As a result, the entire inside of the glass tube 2 is replaced. Since the O group element is inert, the filament 3, molybdenum foil 4, lead-in wire 5, etc. will not be oxidized even when heated by the burner 10 for sealing, and the compound will not be oxidized. Since the filament 3, molybdenum foil 4, lead-in wire 5, etc. do not occur, subsequent steps such as vacuum heating are not required. Although the explanation has been given only to one end of the crow tube 2, it goes without saying that the same fiddling process is carried out at the other end as shown in Fig. 2. Moreover, since the operation and effect at that time are exactly the same as those described above, detailed explanation will be omitted here.

【Effect of the invention】

As explained in 2 below, according to the present invention, a manufacturing method is adopted in which the sealing process is performed using a gas that is a mixture of an element that is a Group 0 element and has a heavier specific gravity than air, and an element that is lighter than air.
Although substitution with inert gas is possible, problems such as precipitation of silica due to the reducing action of hydrogen gas or unevenness on the metal surface due to small explosions due to combination with oxygen, and metal damage due to bonding with oxygen and its re-decomposition occur. This eliminates the problem of oxidation of parts, which can shorten lifespan, and the need for an additional vacuum heating process to prevent characteristic deterioration due to adsorption of hydrogen and nitrogen gas into the glass tube and subsequent release. In addition to being effective in improving performance, such as by extending the length, it is also effective in simplifying the process.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing one embodiment of the sealing process of the tube manufacturing method according to the present invention, FIG. 2 is an explanatory diagram showing the sealing process of another side of the same embodiment, and FIG. FIG. 4 is an explanatory diagram showing the conventional sealing process in order of process. 1----1・Tube 2----Glass tube 2 a-----1 Exhaust pipe 3----Filament 4--111--Molybdenum foil 5----1 Leading wire e- ---One mixed gas e a---Single gas e b---One light gas 10---Burner

Claims (1)

[Claims] In a tube manufacturing method in which a gas is flowed into a tube and a sealing process is performed by heating in this gas atmosphere, a gas containing a mixture of an element that is a group 0 element and has a heavier specific gravity than air and an element that is lighter than air is used. A method for manufacturing a tube, characterized in that the sealing step is performed using a tube.