JPS6358734A - Manufacture of bent bulb shaped fluorescent lamp - Google Patents

Abstract

PURPOSE:To approximately uniformize film thickness of a welded part so that mechanical strength is prevented from falling, by heating and welding the extending side walls of the welded part in such a state that they are turned in the gravity direction when glass bulbs are swung to become nearly parallel to each other. CONSTITUTION:When projecting parts 4 and 4 formed on glass bulbs 1 and 1 are fused to each other, narrow sides of 8-shaped glass bulbs 1 and 1 are turned downwards. Therefore, the upper side of the fused part 6 becomes larger in film thickness than the lower side. when the glass bulbs 1 and 1 are swung in such a state, the fused part 6 are bent outside with the eccentric amount l. when the fused part 6 is bent, extension occurs caused by tension generated outside the central line of this extension. Because this extension occurs on the lower side of the side wall, where the film thickness becomes larger, the film thickness of the fused part 6 is uniformized approximately over the whole surface when the extension due to bending is generated. As a result, mechanical strength can be prevented from locally falling.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to a method for manufacturing a curved tube-shaped fluorescent lamp having a meandering electrical path.

(Prior Art) Recently, compact fluorescent lamps have been developed as power-saving light sources, and these lamps are made by connecting a plurality of glass bulbs, which are arranged approximately parallel to each other, at their ends, so that the lamp as a whole becomes one. A meandering discharge path is formed, a phosphor coating is provided on the inner surface, and discharge electrodes are provided at both ends of the discharge path.

A specific example will be described based on FIGS. 10 to 12. Reference numeral 50 denotes a bulb body, which is composed of two U-shaped glass bulbs 51 and 52. These U-shaped glass bulbs 51 and 52 are connected at one lower end by a welded portion 53, whereby each of the glass bulbs 51 and 52 are electrically connected to each other, thereby forming one meandering electric path as a whole.

Electrodes 54.54 are sealed at the other ends of the glass bulbs 51 and 52 via stem tubes 55.55.

A phosphor coating (not shown) is formed on the inner surface of the bulb body 50, and mercury and a starting rare gas are sealed inside the bulb body 50.

Note that one end of the valve body 50 is attached to a cap 57, and the electrodes 54, 54 are connected to cap bottles 59 through leads 1158.

Fluorescent lamps with this configuration are compact and
Since it is a high-load, high-efficiency type, it is effective as a power-saving light source.

By the way, in a compact fluorescent lamp having such a structure, it is extremely difficult to form the bulb body 1 by discharging oil from a single long glass tube, and therefore, conventionally, it has been developed as shown in FIG. 11. It is constructed by connecting glass bulbs 51 and 52 formed in advance into a U-shape.

When connecting these glass bulbs 5L and 52, conduction is made through the fused portion 53, but! ! The wearing part 53 is the 12th
As shown in the figure, an ejection opening 56.56 is formed at the end of the glass bulb 51.52 by blowing, and these ejection openings 56.56 are fused together. It has become.

In order to form the ejection opening portion 56.56 by blowing, the portion is heated and softened using a burner or the like, and the glass bulb 5 is heated and softened.
Air or inert gas is blown into the tube 1.52 to increase the pressure inside the tube, and this pressure blows out the softened area.

Also, the protruding opening portions 56 and 56 formed in this way are mutually connected! ! In order to do this, a method is adopted in which the protruding openings 56, 56 are butted against each other and then heated with a burner to fuse them together.

Incidentally, since this type of fluorescent lamp is required to be compact, the approximately U-shaped glass bulbs face each other approximately in parallel and are close to each other, as shown in Figure 7. It is important that the parts are joined together.

However, if the glass bulbs face each other substantially parallel to each other and are close to each other, the protrusion openings 56, 56
Since the burner for fusing them cannot enter between the glass bulbs, it is not possible to heat the protrusion openings 56 and 56 evenly over the entire circumference, and many cracks appear, reducing the yield. There is a bad problem.

Therefore, the present inventors are currently researching a method in which a burner for fusing the ejection openings with each other can be inserted between the glass bulbs to heat the ejection openings evenly over the entire circumference. It is.

In this method, the glass bulbs with the protruding openings are connected to each other.
The protruding opening portions are opposed to each other in a figure eight shape,
In this state, simultaneously heat the above protrusion part with a burner! ! Then, the glass bulbs facing each other in the figure eight shape are swung so as to be substantially parallel to each other so as to face each other.

According to this method, since the glass bulbs face each other in a figure-eight shape, a large space is created between the glass bulbs, so that the burner for making the protrusion openings look R can easily enter between the glass bulbs, and the protrusion The mouth can be heated evenly around the entire circumference.

(Problem to be Solved by the Invention) However, as described above, the glass bulbs are faced to each other in a figure eight shape, and in this state, the above-mentioned protruding openings are simultaneously heated and fused with a burner, and then the glass bulbs are bonded to each other. In the method of swinging them so that they are almost parallel and facing each other, a! The fitting portion will be bent and deformed.

When bending deformation occurs in the fused portion, the side wall located on the outside with respect to the center of the curve is stretched, and the wall thickness of the side wall where this stretch occurs becomes thinner, resulting in a problem that the strength becomes weaker.

The present invention aims to provide a method for manufacturing a curved tube fluorescent lamp in which the thickness of the welded part becomes substantially uniform even if the welded part elongates due to swinging, thereby preventing a decrease in mechanical strength. It is something to do.

[Structure of the Invention] (Means for Solving the Problems) The present invention involves swinging the glass pulps facing each other in the figure eight shape so that they are substantially parallel to each other when heat-sealing the ejection openings to each other. When this is done, the side wall on which the m attachment part extends is heated and fused in a posture facing downward, in the direction of gravity.

(According to this method, when the ejection openings are heated and fused together, the molten glass flows downward due to gravity, making the lower side wall thicker and making the glass pulp almost parallel to each other.) When the fused portion is bent and deformed when they are swung to face each other, the m-wall that is within the above-mentioned thickness is stretched, so that the fused portion becomes approximately uniform in thickness.

(Embodiment of the Invention) The present invention will be described below based on an embodiment shown in FIGS. 1 to 9. Figures 1 to 7 show the glass bulb bonding method step by step.
In each of Figures 1 to 7, (a) is due to perspective view, (b)
The figure is a front view.

In the figure, 1.1 is a glass bulb, which is made by bending straight glass pulp into a U-shape in advance, and has a stem 5 at one end, as shown in FIGS. 11 and 12.
5 is sealed and the other end is closed. An electrode 54 is mounted on the stem 55, and an exhaust pipe 2 is attached to the stem 55. A phosphor coating (not shown) is formed on the inner surface of the glass bulb 1.

The glass bulb 1.degree. 1, configured in advance as described above, is supported in a substantially horizontal position with the sealed end facing sideways, as shown in FIG. In this case, the glass bulbs 1, 1 are
As shown in Figure (b), the planes passing through the center line of the U-shape of each glass bulb 1.1 are opposed to each other so as to form an inverted V-shape. Note that this inverted V-shape is a posture in which the other closed end portions to which the stem 55 is not sealed are close to each other and located on the lower side.

As shown in FIG. 2, a blowout burner 3 is inserted between the glass bulbs 1.1, and the blowout burner 3 blows out the planned blowout portion of each glass bulb 1.1.
In other words, the side wall of the closed end is heated. At this time, air or inert gas is injected into the glass bulbs 1, 1 through the exhaust pipes 2, 2 to increase the pressure inside the bulbs 1, 1.

When the area heated by the blowout burner 3 becomes soft, it is pushed by internal pressure and swells, and is then blown out. Therefore, as shown in FIG. 3, an outwardly projecting opening 4.4 is formed at this blowout location.

Thereafter, the glass bulbs 1.1 are brought close to each other while maintaining the inverted V-shape, and the protruding openings 4.4 are welded as shown in FIG.

In this state, as shown in FIG. 5, a welding burner 5 is introduced between the glass bulbs 1.1 to heat the contact portions of the abutted protrusion openings 4.4.

In this case, since the glass bulbs 1, 1 face each other in an inverted V-shape, the donning burner 5 can be positioned between the glass bulbs 1.1, as shown in FIG. 5<b>.

The welding burners 5 are arranged radially around the abutted outlet 4.4 and can therefore heat the circumference of the outlet 4.4 evenly, avoiding 1! due to uneven heating. i
It is possible to prevent defects and cracks from occurring.

At this time, the planes passing through the center lines of the U-shaped curves of the respective glass bulbs 1, 1 are opposed to each other so as to form an inverted eight shape, and this inverted V shape is formed at the other end where the stem 55 is not sealed. It is important that the closed end sides are close to each other and positioned on the lower side.

As the protrusion opening portion 4.4 is heated and softened, the glass bulb 1.
1 are relatively brought into contact and separated several times by a certain amount, as shown in FIG. This improves the compatibility of the molten glass between the protruding openings 4.4, thereby allowing the protruding openings 4.4 to be fused together.

As a result, both glass bulbs 1.1 are electrically connected to each other through the fused portion 6 and are mechanically joined.

Thereafter, while the fused portion 6 is still softened, the glass bulb 1.1 is swung in the direction of arrows A and B in FIG.

The swing center of the glass bulb 1.1 at this time is shown as Olo in FIG. Ru.

Such swinging of the glass bulbs 1.1 bends the fused portion 6 while eccentrically outward by (q center ltλ).At this time, if the pressure inside the glass bulb 1.1 is slightly increased, 11 part 6 becomes thicker and becomes convenient as 1!i! space.

According to such a method, as shown in FIG.
t, the narrow side of the eight-shaped glass bulb 1°1 faces downward, so the wall thickness of the glass bulb 6 when fused is as shown in FIG. 8. That is, when the glass is melted, a flow is generated due to gravity, and the thickness of the lower side becomes larger than that of the upper side.

In this state, as shown in FIG. 7, the glass bulb 1.
When you swing 1,! ! The landing portion 6 is eccentrically outwardly bent by an amount of eccentricity m°C.

When the fused portion 6 is bent, tension is generated on the outside of the bending center line, resulting in elongation.

The side where this elongation occurs is the lower side wall, which has the wall thickness shown in Figure 8. Therefore, if the elongation due to the above-mentioned surface bulging occurs, the fusion bond will occur as shown in Figure 9. The wall thickness of the portion 6 is substantially uniform throughout.

As a result, it is possible to prevent a local decrease in mechanical strength, and there is no possibility that the welded portion 6 will break during the swing or that cracks will occur due to thermal strain during cooling.

In addition, in the above embodiment, the glass bulb was previously formed into a substantially U-shape, but the present invention uses two substantially straight glass tubes at one end. !
This method can also be used when bonding glass bulbs formed into a substantially H-shape together, or when bonding two linear glass tubes together.

In addition, it is necessary to make the glass bulbs 1.1 face each other in a figure-eight shape when fusing the protrusion opening 4.4, and in the processes up to that point, it is not always necessary to make both glass bulbs 1.1 face each other in a figure-eight shape. There isn't.

Furthermore, in order to create a thick wall part as shown in Fig. 8, the side wall on the extension side of the bend may be turned downward only when welding the protruding opening part 4.4, and in other processes, It is not restricted by direction.

Furthermore, when the protrusion openings 4.4 are fused together, it is not necessarily necessary to move the glass bulbs 1.1 toward and away from each other, and the process shown in FIG. 5 can be omitted if they fit well. .

Furthermore, when the glass bulbs 1.1 are arranged to face each other in a figure-eight shape, the angle formed by both glass bulbs 1.1 may be appropriately selected depending on the size of the rotary burner.

[Effects of the Invention] As explained above, according to the method of the present invention, when the protruding opening portions are heated and fused together, when the glass bulbs facing each other in a figure eight shape are swung so that they are substantially parallel to each other, Since the side wall, which is the extending side of the F & tube section, is heated and fused in the direction of gravity, that is, in a downward posture, the molten glass flows downward due to gravity, and the lower side becomes thicker, and the glass becomes thicker. When this fused portion is bent and deformed when the bulbs are swung so that they are substantially parallel to each other and face each other, the thick side wall is stretched.
a! The thickness of the cloth part is approximately equal. Therefore, the mechanical strength of the fused portion becomes uniform, tearing and cranking are prevented, and the yield can be improved.

[Brief explanation of the drawing]

1 to 9 show solid line examples of the present invention.
Figures 7 through 7 are explanatory diagrams showing the manufacturing method in the order of steps, respectively: (a) is a perspective view, (b) is a front view, and Figure 8 is a cross section taken along the line ■-■ in Figure 6(b). Figures 9 and 7 (b)
) is a sectional view taken along line IX-IX in FIG. FIGS. 10 to 12 are diagrams for explaining the conventional technology. 1...Glass bulb, 2...Exhaust pipe, 3...
・Blowout burner, 4...Blowout protrusion, 5.
... Burner required for fusion, 6... Fusion part. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2 <1)) Figure 3 @ Figure 4

Claims (2)

[Claims] (1) A protruding port is formed by heating and softening the side wall on the end side of the glass bulb and blowing it out, and the glass bulbs with the protruding port formed therein are placed in a V-shape with their protruding ports facing each other. In this state, the projecting openings are simultaneously heated and fused by a burner, and then the glass bulbs facing each other in the V shape are swung so as to be substantially parallel to each other so as to face each other. In the method for manufacturing a curved fluorescent lamp, when the protruding openings are heated and fused together, the glass bulbs facing each other in a V-shape are fused while swinging them so that they are substantially parallel to each other. A method for manufacturing a curved tube fluorescent lamp, characterized in that the side wall, which is the extending side of the tube, is heated and fused in a position facing the direction of gravity. (2) The method for manufacturing a curved tube-shaped fluorescent lamp according to claim 1, wherein the glass bulbs are slightly moved toward and away from each other when the projecting openings are fused together.