JPH0211969B2 - - Google Patents

Description

[Detailed description of the invention]

[Object of the Invention] (Industrial Application Field) The present invention relates to a tube that improves the weldability between the current-carrying terminal of the cap and the external conductor led out from the stem. (Prior art) For example, in the case of a high-output fluorescent lamp, a recessed double-contact type cap is attached to both ends of a tubular bulb, and a synthetic resin fitting protrusion provided on the cap is attached to both ends of a tube-shaped bulb. It is known that by fitting into a socket, the energizing terminal in the fitting protrusion and the pin on the socket side are brought into contact with each other to conduct electricity. Incidentally, an external conducting wire led out from the stem of the valve is connected to the above-mentioned current-carrying terminal, and resistance welding is generally employed as this connection means. (Problem to be Solved by the Invention) However, conventionally, current-carrying terminals have been made of copper-based metals such as brass or brass with nickel plating; Weldability with the external conducting wire is poor, and there are problems such as peeling of the welded part after welding. In other words, the thermal conductivity of copper-based metals such as brass or their alloys is much better than that of the external conductor, so the heat generated at the mutual contact with the external conductor during resistance welding is easily diffused. Furthermore, this brass not only has low resistivity and high thermal conductivity, but also contains zinc, which has a low melting point, so it is difficult to handle the heat during welding. As a result, zinc evaporates and bubbles are generated in the welded area, causing welding defects and requiring high current. Therefore, the metals do not melt together at the welded portion between the external conductor and the current-carrying terminal, and the interface becomes loose, making it impossible to obtain a reliable welded portion. In other words, since the nuggets in resistance welding cannot be formed tightly, a reliable weld cannot be obtained. On the other hand, if a large current is applied, the heat generated by the contact area (welded area) becomes too high, which can lead to pin breakage. The present invention was made based on the above circumstances, and its purpose is to provide a tube that prevents the occurrence of welding defects and improves the reliability of the welded portion with the external conductor. It is something. [Structure of the Invention] (Means for Solving the Problems) The present invention comprises an external conductor made of either a aluminum wire, an alloy of iron and nickel, or a metal plated with nickel on iron, and the current-carrying terminal made of nickel or nickel. It is characterized by being made of either an alloy of iron and nickel or a metal plated with nickel on iron. (Function) According to the present invention, the nickel components of the external conductor and the current-carrying terminal are particularly well fused with each other at the joint between the two, making it possible to achieve a reliable and strong joint. (Embodiment) An embodiment of the present invention will be described below based on drawings in which it is applied to a high-output fluorescent lamp. In the figure, 1 is a straight tube type bulb, and a phosphor coating 2 is coated on the inner peripheral surface. The opening edges of a flared portion 4 of a stem 3 are sealed to both end openings (only one shown) of the valve 1, and lead wires 5, 5 are passed through and sealed in the stem 3. Lead wires 5, 5 are internal conductors 6, 6 located within valve 1.
and external conductors 7, 7 led outward from the stem 3.
are connected via the composite wires 8, 8,
The composite wires 8, 8 are sealed through the stem 3. As is known, the summary lines 8, 8 are
The core wire is made of an alloy of 58% iron Fe and 42% nickel nickel, and the outer periphery is coated with copper dioxide, and the outer surface is covered with a borax film.The coefficient of thermal expansion is close to that of stem glass, resulting in good sealing. I'm starting to have sex. The external conductors 7, 7 are made of an alloy of iron (Fe) and nickel (Ni), but they may be made by applying nickel plating to iron (Fe) or by extending the above-mentioned aluminum wires 8, 8 as they are and use this extended portion as the external conductor. . On the other hand, a recessed double contact type cap 10 is attached to both ends of such a straight pipe type valve 1 via an adhesive 9. The base 10 has an electrical insulator 11 made of alloy resin at the center of the end face, and a fitting protrusion 12 that can be fitted into a socket (not shown) is integrally provided at the center of the electrical insulator 11. The inside of this fitting protrusion 12 is formed hollow, and energizing terminals 13, 13 are attached to the inner wall surface of the fitting protrusion 12 so as to be spaced apart from each other and facing each other. The current-carrying terminals 13, 13 are made of iron Fe, nickel Ni, an alloy of iron Fe and nickel Ni, or iron Fe.
Constructed of either metal with nickel plating or stainless steel containing nickel,
These are metals that do not contain copper-based metals. The distal ends of the energizing terminals 13, 13 are integrally folded back to the outside to form connecting pieces 14, 14, respectively. Furthermore, the fitting protrusions 12, 12 have a current-carrying terminal 1 inside them.
Through-holes 15, 15 are provided outside of the wires 3, 13, and the corresponding conductive wires 7, 7 pass through these through-holes 15, 15. The insertion tip side of the external conductors 7, 7 is connected to the connecting piece portion 14,
14, and are resistance welded to the connecting pieces 14, 14, respectively. Note that 16 is a filament coil, and 17 is an exhaust pipe. Next, the effect of the above configuration will be explained based on experimental results. The present inventors prepared external conductors 7, 7 and current-carrying terminals 13, 13 made of various materials, performed welding in various combinations of these two, and examined the welded parts. As a result, the results shown in Table 1 are as follows. The implementation results shown were obtained.

[Table] As is clear from Table 1 above, energizing terminal 1
If a copper-based metal containing copper such as brass is used for the 3 and 13 sides, the external conductor 7,
It can be seen that the welding failure rate is extremely high due to poor compatibility with No. 7. On the other hand, if the current-carrying terminals 13, 13 are made of nickel, an alloy of iron and nickel (stainless copper containing nickel is also acceptable), or a metal plated with nickel on iron, the welded parts with the external conductors 7, 7 It was found that the two metals melted well together and a reliable weld was obtained. That is, since Ni has a low thermal conductivity, a low melting point, and a high electrical resistance, it has conditions suitable for resistance welding, and a sufficient amount of heat can be obtained even with a small current. Therefore,
The external conductors 7, 7 are made of either a aluminum wire, an alloy of iron and nickel, or a metal plated with nickel on iron, and the current-carrying terminal 1
If 3 and 13 are made of nickel, an alloy of iron and nickel (stainless copper containing nickel is also acceptable), or a metal plated with nickel on iron, the above-mentioned small current will be sufficient, and the occurrence of pin cracking will be reduced. It is believed that the contact surfaces of these two reach the melting temperature or a temperature close to it at the same time within a short period of time, thereby preventing the occurrence of welding defects. As can be seen from the above explanation, if both the external conductors 7, 7 and the current-carrying terminals 13, 13 are made of the above-mentioned metal that does not contain copper-based metals, the contact surfaces between these two can be Since defects such as the formation of bubbles and boundary layers can be prevented, weldability is improved, and the welded part does not peel off after welding, which has the advantage of preventing poor conduction. According to experiments, the peel strength when brass and aluminum wire were melted was 5.5 kg,
The peel strength when welding Ni and the composite wire was 9.1 kg. Note that the present invention is not limited to high-output fluorescent lamps, but is applicable to general fluorescent lamps in which a cap pin is protruded from the cap, and an external conductor is inserted into the cap pin and connected at the tip. It is possible to implement even if there is. The cap may also be of a screw-in type,
Therefore, the present invention is not limited only to fluorescent lamps, but can also be applied to incandescent lamps. [Effects of the Invention] As detailed above, according to the present invention, there is no possibility that air bubbles or a boundary layer will be formed on the contact surface between the external conductor and the current-carrying terminal during welding, unlike in the conventional case. Not only does this improve the properties of the weld, but the nickel components of both metals blend well with each other at the contact surface, so the welded part does not peel off after welding, and poor conductivity can be reliably prevented. .

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is an exploded perspective view, FIG. 2 is a sectional view, and FIG. 3 is a cross-sectional view of FIG.
It is an arrow view along a line. 1... Valve, 3... Stem, 7... External conductor, 10... Base, 13... Current-carrying terminal.

Claims (1)

[Scope of Claims] 1. A bulb in which a cap is attached to the end of the valve, and an external conductor led out from the stem of the valve is welded to a current-carrying terminal of the cap, wherein the external conductor is a composite wire or an iron wire. A tube comprising either a nickel alloy or a metal plated with nickel on iron, and wherein the current-carrying terminal is made of nickel, an alloy of iron and nickel, or a metal plated with nickel on iron.