JPS6219016B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for manufacturing a stem in the manufacture of bulbs, particularly fluorescent lamps and light bulbs. The present invention relates to a stem manufacturing method suitable for suppressing the occurrence of cracks in a sealed portion.

[Conventional technology]

Conventionally, in the production of stems for fluorescent lamps and light bulbs, as shown in FIG. has been done. According to such a device, as shown in FIG. 2, the stem 4 on the stem machine 1 is positioned so that the straight line connecting the lead wires 5 is normal to the direction of circular movement of the intermittent transfer of the stem machine 1. It is common to do so. Then, in order to inflate the sealed portion between the flare 6 and the lead wire 5 and give it a predetermined roundness, heating air is blown at a position perpendicular to the straight line connecting the lead wires 5, as shown by arrow A in FIG. A common method is to spray. However, according to this method, the softened sealing glass is sufficiently swollen by the air pressure in the direction perpendicular to the straight line connecting the lead wires 5, and can be given a predetermined roundness as shown in FIG. However, the air pressure diffuses in the direction in which the lead wires 5 are connected, and sufficient air pressure is not applied.As shown in FIG. A problem arises in that the glass contacts the composite wire 7 and the outer lead 8 forming a ridge. Even with such a shape of the sealed portion, the degree of occurrence of cracks is relatively low because sufficient distortion can be removed even with the annealing device 2 with a relatively slow tact. but,
In order to speed up production, the stem process 9 and the mounting process 10 are integrated as shown in Figures 5 and 6, and in this case, the direction of transport of the stem 4 and the lead wire are changed as shown in Figure 7. It is common to match the straight line connecting 5. However, with such an apparatus configuration, there is a problem in that sufficient annealing time cannot be secured in order to increase the speed. Therefore, if the stem is manufactured in the same manner as shown in Figures 1 and 2, that is, by blowing heated air at a position perpendicular to the straight line connecting the lead wires 5, sufficient distortion can be removed. Since this is not possible, cracks occur at a much higher frequency in the sealing portion, resulting in lower production yields. In order to prevent this crack, it is possible to make the summary wire 7 longer, but since making it longer increases the cost and is disadvantageous, some kind of countermeasure has been desired.

[Purpose of the invention]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for manufacturing a tube stem with good yield and good shape, that is, less likely to cause cracks.

[Summary of the invention]

In order to achieve the above object, in the present invention, in the step of manufacturing a stem by heating and sealing the flare and the lead wire, the flare portion is expanded outward from the lead wire in the vicinity of the sealed portion. The tube stem is characterized in that the tube stem is manufactured by blowing heated air from just above the outside of the lead wire toward the root of the lead wire inside the flare in order to separate the lead wires from each other.

With this unique manufacturing method, it is possible to prevent the molten glass from coming into contact with the lead wire in a so-called wet state in the vicinity of the lead wire and flare sealing portion, thereby eliminating the starting point of cracks caused by distortion. I can do it. As a result, the yield of stem manufacturing can be increased.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail with reference to Examples.

FIG. 5 shows a schematic configuration of a stem manufacturing apparatus to which the method for manufacturing a tube stem according to the present invention is applied, and FIG.
The figure shows its side.

As mentioned above, this device is a device that integrates the stem process 9 and the mounting process 10, and the upper link 11 is provided with a flare 6 and a holder (not shown) for the exhaust pipe 13, and the lower link 12 is equipped with a lead. A holder (not shown) for the wire 5 is provided, and as shown in FIG. 7, the linear direction connecting the two lead wires 5 is aligned with the direction in which the stem 4 is transferred, and the parts constituting the stem 4 are removed from the IN. The stem is manufactured while the upper link 11 and the lower link 12 are aligned. At the station where only the link 11 is installed, the mount is manufactured in the mounting process 10, and the completed mount is discharged from the OUT. . In this apparatus, during the stem step 9, heated air is blown toward the base of the lead wire 5 from just above the outside of the lead wire 5 in the direction of arrow B, as shown in FIGS. 7 and 8.

By the above method, the flare 6 and the lead wire 5 are
As shown in part C in Figure 8, the inside of the sealed part with
It can be molded to expand outward, prevent the molten glass from coming into contact with the lead wire 5 in a so-called wet state, and eliminate the annealing process.
It has become possible to eliminate the starting point of crack occurrence just by dispersing the distortion appropriately.

〔Effect of the invention〕

As explained above, the method of the present invention prevents molten glass from coming into contact with the lead wire in a so-called wet state in the vicinity of the lead wire and the flare sealing part in manufacturing a tube stem. This makes it possible to eliminate the origin of cracks caused by distortion, thereby increasing the yield of stem production and furthermore, the reliability of finished lamps against leaks. In addition, by eliminating areas that are likely to cause cracks, cracks are less likely to occur even without complete distortion removal, making it possible to eliminate the annealing process, reducing equipment costs, and
Furthermore, it becomes possible to reduce the number of times of delivery, and it becomes possible to reduce the defective rate. Further, by reducing the wetted area of the lead wire, it is possible to shorten the length of the expensive composite wire portion, resulting in cost reduction.

[Brief explanation of the drawing]

Figure 1 is a diagram for explaining the conventional stem and mount manufacturing process, Figure 2 is a diagram showing the conventional air blowing direction, and Figures 3 and 4 are diagrams showing the shape of the stem manufactured by the conventional method. Figures 5 and 6 are diagrams for explaining the process when the stem and mount manufacturing processes are integrated, Figure 7 is a diagram showing the air blowing direction according to the method of the present invention, and Figure 8 is a diagram for explaining the process of manufacturing the stem and mount. It is a figure showing the shape of the stem manufactured by the invention method. 1... Stem machine, 2... Annealing device, 3...
Mounting machine, 4... Stem, 5... Lead wire, 6
...Flare, 7...Dimension wire, 8...Outer lead, 9...Stem process, 10...Mount process, 11...Upper link, 12...Lower link, 13...Exhaust pipe.

Claims (1)

[Claims] 1. In a method of manufacturing a stem by aligning the stem transfer direction with the straight line connecting the two lead wires and integrating the stem process and mounting process, the flare and the lead wires are sealed by heating and sealing. Heat is applied from almost directly above the outside of the lead wire toward the root portion of the lead wire inside the flared portion in order to separate the flare portion from the lead wire by inflating the flare portion near the attachment portion to the outside. A method of manufacturing a tube stem characterized by blowing air.