JPH0536356A - Sealing device and sealing method for tubular bulb - Google Patents

Abstract

PURPOSE:To provide the sealing device of a tubular bulb which satisfactorily heats the side wall on the inside between two straight line sections, prevents the breakage and defective sealing due to the dispersion of heating, and improves the yield. CONSTITUTION:A rotary chuck 10 holding a bulb 1 arranged in parallel with two straight line sections 2, 2 and rotating the bulb 1 around the center line passing through the intermediate point between the straight line sections 2, 2 used as the rotation center and burners 20, 20 installed on the outside in the radial direction of the rotated bulb 1 and heating and sealing the end sections of the straight line sections 2, 2 of the bulb 1 are provided, and the burners 20, 20 inject gas flames in the eccentric directions against the rotation center. The gas flames injected from the burners 20, 20 satisfactorily heat the side wall on the inside between the straight line sections 2, 2, and the straight line sections 2, 2 are heated uniformly in the peripheral direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for sealing a valve in which two straight portions are arranged in parallel by heating the ends of these straight portions by a burner.

[0002]

2. Description of the Related Art Recently, as fluorescent lamps have become smaller, U
B-shaped and W-shaped bent fluorescent lamps have been developed and are being sold as compact fluorescent lamps. These bent type fluorescent lamps have a structure in which two linear portions are arranged in parallel, and an electrode mount is sealed at the ends of these linear portions. With respect to the lamp having such a structure, the current state of mount sealing work will be described with reference to FIGS. 4 and 5.

FIG. 4A shows a U-shaped fluorescent lamp (F
It is a disassembled perspective view which shows the structure of DL-EX), 1 is a U-shaped glass bulb. The valve 1 has straight line portions 2 and 2 which are continuous with both ends of a bent portion in the central portion, and these straight line portions 2 and 2 are aligned with each other. A phosphor coating (not shown) is formed on the inner surface of the bulb 1.

The stems 3 and 3 of the mount are sealed at the open ends of the straight portions 2 and 2. The stems 3 and 3 are flare stems, which penetrate the pair of lead wires 4 and 4 airtightly,
A filament 5 is laid between these lead wires 4 and 4. An exhaust pipe 6 is connected to the stems 3 and 3.

The stems 3 and 3 are inserted into the openings of the linear portions 2 and 2 of the valve 1, and the openings of the linear portions 2 and 2 are heated by a burner described later to soften the stems. 3, 3 are welded to the valve 1. Therefore, the valve 1 is sealed by the stems 3 and 3. When such sealing is completed, the inside of the valve 1 is exhausted through the exhaust pipe 6 and mercury and an inert gas are enclosed to completely cut off the exhaust pipe 6. Then, the bulb 1 is covered with the base 7 on the ends of the linear portions 2 and 2, and the base 7 and the bulb 1 are bonded with an adhesive to complete the lamp. In such a lamp, when the stems 3 and 3 are sealed to the linear portions 2 and 2 of the bulb 1, a device as shown in FIG. 3B is used.

That is, 10 is a valve chuck, for example, which holds the central bent portion of the valve 1 and is rotated by the rotation of the drive shaft 11. A mount holder 12 supports the exhaust pipes 6, 6 of the stems 3, 3 and is rotated by the rotation of the drive shaft 13. The drive shaft 11 of the valve chuck 10 and the drive shaft 13 of the mount holder 12 are coaxial with each other and are adapted to rotate in the same direction in synchronization with each other.

In this case, the valve 1 is rotated with the center point between the linear portions 2 and 2 as the rotation center axis OO, and the linear portion 2 and
2 revolves around the central axis of rotation OO. At this time, the mount holder 12 also rotates around the rotation center axis O-O, and the stems 3 supported by the mount holder 12 integrally rotate while being inserted into the linear portions 2 and 2.

Outside the swirl area, the sealing burner 1 has the same height as the openings of the linear portions 2 and 2.
5, 15 are provided. The burners 15 and 15 face each other at an angle of 180 degrees with the rotation center axis O-O interposed therebetween, and horizontally inject the gas flame toward the rotation center axis O-O direction.

With the stems 3 and 3 inserted in the straight portions 2 and 2 of the valve 1, the valves 1 and the stems 3 and 3 are swiveled around the rotation center axis OO, and in this state, the burners 15 and 15 are rotated. Blow out a gas flame from.

Then, since the ends of the straight portions 2 and 2 of the valve 1 turn, they are heated by the burners 15 and 15, and the ends of the straight portions 2 and 2 are softened so that the stems 3 and 3 are melt-bonded. .

[0011]

However, in the case of the sealing device as described above, the burners 15, 15 are opposed to each other at an angle of 180 degrees with the rotation center axis OO interposed therebetween.
Moreover, as shown in FIG. 6, the flames of these burners have a temperature distribution that the temperature of the tip of the burner is the highest in the range of several mm, and since the tip of such a flame is directed to the center of rotation,
Heat unevenness occurs in the pair of straight portions 2 and 2.

That is, FIG. 5 shows a heating state of the valve, and a hatched area shows a heated area. FIGS. 5 (A) to 5 (E) show the heating state of each of the straight line portions 2 and 2 when it is turned clockwise, and the thicker the shaded area, the higher the temperature.

As can be seen from this figure, the conventional burner 1
Since 5 and 15 face each other at an angle of 180 degrees and the gas flame faces the center, in the case of Fig. (A), the gas flame hits the outer surfaces of the straight portions 2 and 2 facing each other at an angle of 180 degrees. The inner side wall is not heated, and the heat of the gas flame does not reach the inner side walls of the straight portions 2 and 2 sufficiently even if the valve 1 swirls as shown in FIGS. At the position shown in the figure, the flames of the burner start to flutter with each other.
Even if rotated, the side walls on the inner surface side of the linear portions 2 and 2 may not be sufficiently heated.

For this reason, uneven softening occurs due to uneven heating, the thickness becomes uneven, the glass is distorted, the bulb is damaged, and a hole is opened in the sealing portion to cause sealing failure.
There was a problem such as a decrease in yield.

The present invention has been made in view of the above circumstances. An object of the present invention is to satisfactorily heat an inner side wall between two straight line portions, and to prevent damage or defective sealing due to uneven heating. It is an object of the present invention to provide an apparatus and a method for preventing and improving the yield of a bulb valve.

[0016]

The first aspect of the present invention is to hold a valve in which two straight portions are arranged in parallel, and to swivel the valve with a center line passing through an intermediate point between these straight portions as a rotation center. And a burner that is installed outside in the radial direction of the valve that is swung and that heats and seals the end of the straight portion of the valve, and the burner is in a direction eccentric to the center of rotation. It is characterized in that it is installed so as to inject a gas flame toward it.

The second aspect of the present invention is to hold a valve having two linear portions arranged side by side, and to turn the valve around a center line passing through an intermediate point between the linear portions as a rotation center. A burner that is installed radially outward of the swirled valve and that heats and seals the end portion of the straight portion of the valve, and the burners are provided in a plurality spaced apart from each other in the circumferential direction with respect to the center of rotation. , 180 degrees opposite to each other are installed, and the plurality of burners are arranged so as to inject a gas flame toward the center of rotation.

The third aspect of the present invention is to hold a valve having two straight line portions arranged side by side, and to turn the valve around a center line passing through an intermediate point between the straight line portions as a rotation center. In a method for sealing a bulb valve, which heats and seals an end portion of a straight portion of the valve with a burner from the outside in the radial direction of the valve, while rotating the valve, the burner is eccentric with respect to the rotation center. It is characterized in that the gas flame is jetted in the above direction to heat-seal.

Further, in the fourth aspect of the present invention, a valve having two straight line portions arranged in parallel is held, and the valve is turned around a center line passing through an intermediate point between the straight line portions as a rotation center, and this turn is performed. In the method of sealing a bulb valve, wherein the end of the straight portion of the valve is heated and sealed by a burner from the outside in the radial direction of the valve, while rotating the valve,
It is characterized in that a plurality of burners are used to inject a gas flame toward the rotation center from a direction away from the rotation center in the circumferential direction so as to avoid an opposing position of 180 degrees, and heat sealing is performed.

[0020]

In general, the burner flame has a property that the heat propagation to the heated object increases as the burner flame hits the heated object at a right angle. According to the apparatus and method described in the first to fourth aspects of the present invention, the burner flame moves outward from the center of rotation. Since the temperature tends to rise in the facing part,
It is difficult to raise the temperature by applying a burner flame obliquely to this part, and it is easy for the burner flame to hit the inner side wall between the straight parts of the valve at a right angle. The temperature of the side wall can be increased, and the straight portions are evenly heated in the circumferential direction.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIG. Although FIG. 1 shows the heating state of the valve, the basic structure may be the same as that of the conventional one shown in FIG. 4, and therefore detailed description thereof will be omitted.

The difference of this embodiment from the conventional case is the direction of the burners 20, 20. That is, in this embodiment, the sealing burners 20 and 20 are provided outside the swirl region and have the same height as the openings of the straight portions 2 and 2 of the valve. These burners 20 and 20 have central axes of rotation OO.
They are arranged at positions facing each other at an angle of 180 degrees with respect to each other, and each is configured to inject a gas flame in the horizontal direction. However, in the case of the present embodiment, the injection holes of these sealing burners 20, 20 are oriented eccentrically with respect to the rotation center axis OO, and the gas flames ejected from these injection holes have the rotation center axis O-. They are installed so as to be eccentric to the -O direction and symmetrical to each other.

In the case of such a construction, as can be seen from FIG. 1, since the gas flames of the burners 20, 20 are oriented eccentrically with respect to the rotation center axis OO, FIGS. As can be understood from the figure, the heat of the gas flame reaches the outer side surfaces of the straight portions 2 and 2 and the inner side walls between them due to the turning of the valve, and after one rotation, the side walls of the straight portions 2 and 2 are circumferentially arranged. Is heated almost evenly.

As a result, uneven heating of the linear portions 2 and 2 is prevented, and unevenness in wall thickness due to uneven softening does not occur. Therefore, the glass is distorted and the bulb is damaged,
A defect such as a hole being opened in the sealing portion to cause a sealing failure is solved, and the yield is improved. Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 2 also shows the heating state of the valve, and the basic configuration may be the same as that of the conventional one shown in FIG. 4, so detailed description thereof will be omitted.

The difference of this embodiment from the first embodiment is the arrangement of the burners 30, 30. That is, in this embodiment,
Sealing burners 30 and 30 are provided outside the swirl region and have the same height as the openings of the linear portions 2 and 2 of the valve. −
They are arranged so as to avoid positions facing each other at an angle of 180 degrees with O interposed therebetween. That is, the sealing burners 30, 30 are arranged at an angle of, for example, 120 degrees, and the injection holes of the sealing burners 30, 30 are oriented in the rotation center axis OO direction.

In the case of such a configuration, as can be seen from FIG. 2, the gas flames of the burners 30, 30 are directed to the rotation center axis OO, so that it can be understood from FIGS. (A) to (E). In addition, the heat of the gas flame reaches the outer side surfaces of the linear portions 2 and 2 and the inner side walls between them due to the turning of the valve, and after one rotation, the side walls of the linear portions 2 and 2 are heated substantially evenly in the circumferential direction. It Therefore, also in the case of this embodiment, the straight line portion 2,
The heating variation of 2 is prevented.

In the present invention, the linear portions 2, 2 of the valve 1 are
The present invention is not limited to the case where the stems 3 and 3 are respectively sealed, and is also applicable to the sealing of the valve as shown in FIG. 3, for example.

That is, in the case of FIG. 3, the stem 3 is sealed in one straight line portion 2a of the U-shaped valve, and the other straight line portion 2b is
The end portion which is formed long in advance is heated and closed by a burner. Even in such a case, since both linear portions 2a and 2b are eventually closed, both can be simultaneously sealed by using the sealing device of the present invention. In addition,
Two such bulbs are used to make a double U-shaped fluorescent lamp by communicating with each other by melting and connecting the bulbs at their closed ends.

[0029]

As described above, according to the present invention, the gas flame injected from the burner can raise the temperature of the inner side wall between the straight portions, so that the straight portions are evenly distributed in the circumferential direction. Be heated. For this reason, uneven heating due to unevenness in the straight portion is prevented, and uneven thickness due to uneven softening does not occur. Therefore, defects such as distortion of the glass and breakage of the bulb, and holes in the sealing portion resulting in defective sealing are eliminated, and the yield is improved.

[Brief description of drawings]

FIG. 1 is a view showing a relationship between a burner arrangement and a heating state of a sealing device according to a first embodiment of the present invention, and FIGS.
The figure is an illustration of the heating state.

FIG. 2 shows the relationship between the arrangement of burners and the heating state of the sealing device according to the second embodiment of the present invention, and FIGS.
The figure is an illustration of the heating state.

FIG. 3 is a diagram illustrating a sealing device according to a third embodiment of the present invention.

FIG. 4 is a view for explaining a sealing process in a conventional case,
(A) is an exploded perspective view showing the configuration of the U-shaped fluorescent lamp, (B) is an explanatory view of the sealing device.

FIG. 5 shows the relationship between the arrangement of burners and the heating state in the conventional sealing device, and FIGS. 5A to 5E are explanatory views of the heating state.

FIG. 6 is a diagram showing a temperature distribution of a gas flame.

[Explanation of symbols]

1 ... Valve, 2 ... Straight part, 3 ... Stem, 5 ... Filament, 20, 30 ... Sealing burner, O ... Rotation center.

Claims (4)

[Claims] 1. A swivel chuck that holds a valve in which two straight portions are arranged in parallel, and swivels the valve around a center line passing through an intermediate point between the straight portions as a rotation center; In a bulb valve sealing device provided with a burner that is installed radially outward and that heats and seals the end of the straight portion of the valve, the burner is directed toward a direction eccentric to the center of rotation. A bulb valve sealing device, which is installed so as to eject a gas flame. 2. A swivel chuck that holds a valve in which two straight parts are arranged in parallel, and swivels the valve around a center line passing through an intermediate point between the straight parts, and a swivel valve that is swung. In a tube bulb sealing device provided with a burner that is installed radially outward and that heats and seals the end portion of the straight portion of the valve, the burner is circumferentially separated from the rotation center. A sealing device for a bulb valve, wherein a plurality of burners are provided so as not to face each other at 180 degrees, and the plurality of burners are arranged to inject a gas flame toward a rotation center. 3. A valve having two linear parts arranged in parallel is held, and the valve is turned around a center line passing through an intermediate point between the linear parts as a center of rotation, and the valve is rotated radially outside of the turned valve. In a method of sealing a bulb valve, in which a straight end of the valve is heated and sealed by a burner from one side, a gas flame is directed from the burner in a direction eccentric to the center of rotation while rotating the valve. A method for sealing a bulb valve, comprising: 4. A valve having two straight portions arranged in parallel is held, the valve is swung about a center line passing through an intermediate point between the straight portions as a rotation center, and the swiveled valve is radially outside. In a method for sealing a bulb valve, in which a straight end of the valve is heated and sealed by a burner from one side, the valve is swung while facing 180 degrees apart from the center of rotation in the circumferential direction. A method for sealing a bulb valve, wherein a plurality of burners are used to inject a gas flame toward the center of rotation from a direction away from the position to perform heat sealing.