JP2002203517A - Double-tube fluorescent lamp and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a double-tube fluorescent lamp superior in a strength against a thermal impact/mechanical impact. SOLUTION: As for an inner tube 10 of a structure wherein lead-in wires 4, 4' are respectively protruded to the outside from respective electrodes 3, 3' arranged at both inner ends after penetrating respective sealing end parts 11, 11', a bead glass 8 for an outer tube is mounted on only one of the lead-in wires 4, 4' protruded from the both respective sealing end parts 11, 11', and the inner tube 10 is inserted into a glass tube 6 for the outer tube, and one outer tube sealing end part 22 is constituted by directly sealing and fixing the lead-in wire 4' by the glass tube 6 for the outer tube wherein the bead glass 8 for the outer tube is not mounted, and the other outer tube sealing end part 21 is constituted by sealing and fixing the lead-in wire 4 by the glass tube 6 for the outer tube together with the bead glass for the outer tube wherein the bead glass 8 for the outer tube is mounted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-tube fluorescent lamp and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, a double tube fluorescent lamp has a structure shown in FIG. First, the inner tube 10 is formed by forming a phosphor coating 2 as a luminous body on the inner surface of the glass tube 1, and forming both ends 1 of the glass tube 1.
Electrodes 3, 3 'and lead wires 4, 4' are arranged at 1, 11 ', and these lead wires 4, 4' are connected by bead glass 5, 5 'to both ends 11, 11' of glass tube 1. The glass tube 1 has a structure in which both tube ends 11, 11 'are hermetically sealed. And inside the glass tube 1, both tube ends 1
1,11 'to bead glass 5,5' to lead wire 4,
When the 4 'is fixedly integrated, a Ne-Ar mixed gas is sealed.

The outer tube 20 is provided with the outer tube bulb 6 covering the glass tube 1 of the inner tube 10 with a gap 7 therebetween, and the same introduction projecting from both tube end sealing portions 11, 11 'of the inner tube 10. Line 4,
Both ends 21 and 21 'of the outer tube are fixedly integrated with the outer tube beads 4 and 8' by bead glass 8 and 8 'for the outer tube, and both ends of the outer tube valve 6 are sealed in a confidential manner. The gap 7 between the inner tube 10 and the outer tube 20 is in a vacuum state or a state in which a small amount of rare gas is sealed.

[0004] A manufacturing process of the conventional double tube fluorescent lamp will be described with reference to FIG. As shown in FIGS. 7A and 7B, the already assembled inner tube 10 is attached to the outer tube beads 4 and 4 'projecting from both tube end sealing portions 11 and 11', respectively. Glasses 8, 8 'are mounted. In this state, the inner tube 10 is inserted into the straight outer glass tube 60 that becomes the outer tube bulb 6.

[0005] Next, as shown in FIGS.
The end of the outer glass tube 60 corresponding to the portion where the outer tube bead glass 8 ′ is mounted is heated to fix and integrate the outer tube glass beads 8 ′ with the heated portion of the outer glass tube 60. One of the tube ends 21 'is formed.

Next, as shown in FIGS. 1 (c) and 1 (d),
The getter 30 is inserted into the other surplus portion 61 of the outer glass tube 60, and the getter 3 is evacuated while the outer glass tube 60 is evacuated.
Both ends of the insertion portion 2 are heated, so that one end of the extra portion 61 of the outer glass tube 60 near the inner tube 10 of the getter 30 is squeezed, and the other end is sealed with the getter 30.

Subsequently, as shown in FIG. 1E, a portion of the outer glass tube 60 corresponding to the bead glass 8 for the outer tube attached to the introduction line 4 of the inner tube 10 is heated to bead glass. 8 and fixed to the outer tube end portions 21 and 21 '.
Form the outer bulb 6 sealed together. At this time, the impurity gas generated by the heating is adsorbed by the getter 30, and the impurities in the gap 7 between the outer pipe valve 6 and the inner pipe 10 are removed.

Thereafter, as shown in FIGS. 1E and 1F, the extra glass tube surplus portion 61 is cut off from the outer tube sealing end portion 21 to obtain the conventional double tube fluorescent light shown in FIG. A lamp will be obtained.

[0009]

However, in the conventional double-tube fluorescent lamp having the above-described structure, the introduction wires 4, 4 'projecting from the sealing portions 11, 11' at both ends of the inner tube 10 in the manufacturing process. The bead glasses 8, 8 'for the outer tube are mounted and fixedly integrated at both ends of the outer tube bulb 6, so that the axes of the bead glasses 4-8 for the inner tube and 4'-8' are easily displaced. In some cases, the inner tube 10 cannot be inserted smoothly into the tube 60. As a result, the resulting conventional double tube fluorescent lamp is structurally weak against thermal shock and mechanical shock. There was a problem that could be done.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and an object of the present invention is to provide a double-tube fluorescent lamp excellent in thermal shock and mechanical shock strength. I do.

Another object of the present invention is to provide a method for manufacturing a double-tube fluorescent lamp capable of manufacturing a double-tube fluorescent lamp excellent in thermal shock and mechanical shock strength.

[0012]

The double-tube fluorescent lamp according to the first aspect of the present invention has an electrode disposed at both ends of the inner tube, and has a lead-in wire protruding outside through a sealing end.
The outer glass bead glass is attached to only one of the introduction lines protruding from both the sealing ends of the inner tube, the inner tube is inserted into the outer tube bulb, and the outer tube bead glass is attached. An introductory line is directly sealed to one end of the outer tube bulb, and the introductory line to which the outer tube bead glass is mounted is sealed to the other end of the outer tube valve together with the outer tube bead glass.

In the double tube fluorescent lamp according to the first aspect of the present invention,
The structure of one of the sealed ends of the outer tube is a structure in which the introduction line to which the bead glass for the outer tube is not attached is directly sealed to one end of the outer tube valve, and the structure of the other sealed end is Since the lead wire attached with the outer tube bead glass is sealed to the other end of the outer tube valve together with the outer tube bead glass,
In the manufacture, the bead glass for the outer tube is attached to each of the introduction lines at both ends, and the glass tube for the outer tube is sealed with the glass tube for the outer tube. The end that needs to be aligned with the bead glass for the inner tube and the bead glass for the outer tube that is sealed to the sealed end of the inner tube in the part becomes only one end, and that much,
The probability of misalignment between the inner and outer bead glasses is also halved. Therefore, structurally, it is possible to reduce the probability of manufacturing a product having a low strength against thermal shock and mechanical shock, and to manufacture a product having good quality.

According to a second aspect of the present invention, there is provided a method of manufacturing a double tube fluorescent lamp, comprising: an inner tube having a structure in which an introduction wire projects outward from a respective electrode disposed at both ends through a sealing end; Attach the bead glass for the outer tube to only one of the guide lines projecting from each of the sealing ends, insert the inner tube into the glass tube for the outer tube, and insert the bead glass without the bead glass for the outer tube into the guide tube. The outer tube is directly sealed with an outer tube glass tube to form one outer tube sealed end, and the lead wire to which the outer tube bead glass is attached is sealed together with the outer tube bead glass by the outer tube glass tube. To constitute the other outer tube sealing end.

According to the method of manufacturing a double-tube fluorescent lamp of the second aspect of the present invention, a double-tube fluorescent lamp having the structure of the first aspect of the present invention can be manufactured. The probability of manufacturing a double-tube fluorescent lamp that is weak against the mechanical impact strength is reduced, and a high-quality square bequest lamp can be manufactured.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows the structure of a double-tube fluorescent lamp according to one embodiment of the present invention. In the double tube fluorescent lamp of the present embodiment, the structure of the inner tube 10 is the same as that of the conventional inner tube 10 shown in FIG. Therefore, common elements are denoted by the same reference numerals.

The feature of this embodiment is that the outer tube 20
In the structure of the sealing ends 21 and 22 of the inner tube 10.
That is, the outer pipe valve 6 is provided with a gap 7 so that the inner pipe 10
And the introduction line 4 protruding from one of the sealing ends 11 of the inner tube 10 is fixedly integrated with one end of the outer tube bulb 6 by the bead glass 8 for the outer tube to form an airtight sealing end. The unit 21 is constituted. On the other hand, the introduction line 4 'protruding from the other sealing end 11' of the inner tube 10 is not attached with the bead glass for the outer tube as in the conventional example,
It is directly fixed and integrated with the other end of the outer pipe valve 6 to form an airtight sealing end 22.

Thus, in the double-tube fluorescent lamp of the first embodiment, in the manufacture thereof, the introduction wires 4 at both ends are used.
The conventional structure in which bead glasses 8 and 8 'for the outer tube are attached to each of the tubes 4' and sealed by the glass tube 60 for the outer tube.
Compared with the method of manufacturing a double tube fluorescent lamp, the bead glass 5 'for the inner tube and the bead glass 8' for the outer tube, which are sealed at one end to the sealing end 11 'of the inner tube 10, are provided. The need for alignment is eliminated, and the probability of misalignment of the inner and outer bead glass is reduced by half, and the probability of manufacturing a structure that is weak against thermal shock and mechanical shock strength is reduced. Then, high quality products can be manufactured.

Next, a method of manufacturing a double tube fluorescent lamp according to a second embodiment of the present invention will be described with reference to FIG. As shown in FIGS. 3A and 3B, the already assembled inner tube 10 is connected to only one of the introduction lines 4 and 4 'projecting from both tube end sealing portions 11 and 11'. Attach bead glass 8 for outer tube. In this state, the inner tube 10 is inserted into the straight outer glass tube 60 that becomes the outer tube bulb 6.

Next, as shown in FIGS.
The end of the outer glass tube 60 corresponding to the end of the introduction wire 4 'to which the bead glass for an outer tube is not attached is heated to be fixedly integrated with the introduction wire 4', and one of the sealing ends 22 of the outer tube 20 is sealed. To form

Next, as shown in FIGS.
The getter 30 is inserted into the other surplus portion 61 of the outer glass tube 60, and the getter 3 is evacuated while the outer glass tube 60 is evacuated.
The both ends of the 0 insertion portion are heated, and one end of the extra portion 61 of the outer glass tube 60 near the inner tube 10 of the getter 30 is squeezed to seal the other end of the getter 30.

Subsequently, as shown in FIG. 2E, a portion of the outer glass tube 60 corresponding to the bead glass 8 for the outer tube attached to the introduction line 4 of the inner tube 10 is heated to bead glass. 8 is fixedly integrated to form an outer tube sealing end 21 and both ends 21 and 22 are sealed together.
To form At this time, the impurity gas generated by the heating is adsorbed by the getter 30, and the impurities in the gap 7 between the outer pipe valve 6 and the inner pipe 10 are removed.

Thereafter, as shown in FIGS. 3 (e) and 3 (f), the outer glass tube surplus portion 61 is cut off from the outer tube sealing end portion 21 to obtain a double tube fluorescent light having the structure shown in FIG. Get the ramp.

The double tube fluorescent lamp obtained by this manufacturing method has the structure of the embodiment shown in FIG. 1, but as described above, unlike the method of the conventional example, one end portion Since the lead-in wire 4 'is directly sealed at the end of the outer tube bulb 6 without mounting the bead glass 8' for the outer tube,
There is no need to center the bead glass 5 'for the inner tube and the bead glass 8' for the outer tube sealed at one end at the sealing end 11 'of the inner tube 10, so that the inner and outer beads are correspondingly reduced. The probability of misalignment of the glass is also halved, and the probability of manufacturing a structure that is weak against thermal shock and mechanical shock strength is reduced, so that a high-quality double-tube fluorescent lamp can be manufactured.

<Examples> The thermal shock strength and the mechanical shock strength of the double-tube fluorescent lamp manufactured by the manufacturing method of the conventional example shown in FIG. 6 and the manufacturing method of the embodiment of the present invention shown in FIG. Was measured, and the results are shown.

1. The comparison of thermal shock strength was performed for the conventional product and the product of the present invention with the following specifications.

(A) Lamp outer diameter: Inner tube bulb = φ1.8
mm (t0.2 mm), outer bulb = φ2.4 mm (t
0.2 mm).

As shown in FIG. 3, the test method was such that the temperature of the molten solder in the solder bath was changed to 300, 350, and 380 ° C.
1 s for 5 mm from the tube end of the lamp sealing parts 21 ′ and 22
After immersion for 5 seconds with ec, the process of leaving at room temperature for 10 seconds or more and performing cold water immersion at 25 ° C. or less was defined as one cycle, and the generation of cracks in the sealing portions 21 ′ and 22 was confirmed.
The remaining number is compared. Confirmation of crack is 1,
Performed at 3, 5, and 10 cycles.

The results are shown in Table 1 below.

[0030]

[Table 1] From this test result, it can be seen that the temperature of the molten solder liquid is 3 in the case of the conventional product.
When the temperature reached 50 ° C., after 10 cycles, cracks were observed in 2 out of 10 tubes. When the temperature of the molten solder liquid reached 380 ° C., two more cracks were observed after the first cycle. On the other hand, in the example of the present invention, the temperature of the molten
At ℃, no damage was seen in one of the ten products. From this, it was found that the thermal shock resistance of the example product of the present invention was improved as compared with the conventional product.

3. The mechanical impact strength of the conventional product and the product of the embodiment of the present invention were measured for the following specifications.

(A) Lamp outer diameter: Inner bulb = φ1.8
mm (t0.2 mm), outer bulb = φ2.4 mm (t
0.2 mm).

(B) Lamp length: 50 mm, 100 m
m, 150mm, 200mm, 250mm, 300m
m.

The test method is to measure the mechanical load limit value. For the conventional product and the product of the present invention, fix the lamp of each of the above-mentioned lamp lengths on the base plate, and set the lower one to the height at which 500G works. While changing the height from the base plate, it was dropped with the base plate facing down to check whether it was damaged.

FIG. 4 shows the test results. From this test result, in the case of the conventional product, a lamp with a lamp length of 200 mm is broken by a shock of 500 G, a lamp with a length of 250 mm is broken by a shock of 450 G, and a lamp with a length of 300 mm is broken by 400 G.
It was damaged by the impact of G. On the other hand, in the case of the products of the examples of the present invention, none of these lamp lengths was broken by the impact of 500G. Thus, it was found that the mechanical shock resistance of the example product of the present invention was improved as compared with the conventional product.

[0036]

As described above, according to the double-tube fluorescent lamp of the present invention, in the manufacture thereof, the lead-in wire to which the bead glass for the outer tube is not attached is directly sealed to one end of the outer-tube bulb. It is possible to adopt a method of sealing the lead wire on which the bead glass for a tube is mounted together with the bead glass for the outer tube to the other end of the outer tube valve. 2 of conventional structure in which bead glass for a tube is attached and sealed with a glass tube for an outer tube
Compared to the method of manufacturing a double tube fluorescent lamp, it is necessary to align the bead glass for the inner tube and the bead glass for the outer tube sealed at one end with the sealing end of the inner tube. Only one end is used, and the probability of misalignment of the bead glass inside and outside is halved by that amount, which reduces the probability of manufacturing a structure that is weak against thermal shock and mechanical shock strength. , Can increase the yield.

According to the double tube fluorescent lamp manufacturing method of the second aspect of the present invention, the double tube fluorescent lamp having the structure of the first aspect of the present invention can be manufactured with a high yield.

[Brief description of the drawings]

FIG. 1 is a sectional view of a double-tube fluorescent lamp according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a method for manufacturing a double-tube fluorescent lamp according to a second embodiment of the present invention.

FIG. 3 is an explanatory diagram of a thermal shock strength test method performed on a product of the present invention and a conventional product.

FIG. 4 is a graph showing test results of mechanical impact strength according to lamp length of a product of the present invention and a conventional product.

FIG. 5 is a cross-sectional view of a conventional double tube fluorescent lamp.

FIG. 6 is an explanatory diagram of a method for manufacturing a conventional double tube fluorescent lamp.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inner tube glass 2 Phosphor coating 3, 3 'Electrode 4, 4' Introducing line 5, 5 'Bead glass 6 Outer tube valve 7 Clearance 8 Bead glass for outer tube 10 Inner tube 11, 11 Sealing end part 20 Outer tube 21 Sealed end 22 Sealed end

Claims (2)

[Claims] 1. An introduction line protruding outside from each of electrodes disposed at both ends of an inner tube through a sealing end, and one of the introduction lines protruding from each of the sealing ends of the inner tube. Only the bead glass for the outer tube is attached, the inner tube is inserted into the outer tube valve, and the lead wire without the bead glass for the outer tube is directly sealed to one end of the outer tube valve. A double-tube fluorescent lamp comprising a guide wire having a bead glass for a tube mounted thereon and the other end of the outer tube bulb sealed together with the bead glass for an outer tube. 2. An inner tube having a structure in which a lead wire protrudes to the outside through a sealing end from each of electrodes disposed at both inner ends, and one of the lead wires protruding from each of the two sealing ends. Only the bead glass for the outer tube is attached, the inner tube is inserted into the glass tube for the outer tube, and the lead-in wire not fitted with the bead glass for the outer tube is directly sealed by the outer tube glass tube to one of the outer tubes. Forming an outer tube sealing end portion, and sealing the introduction line to which the outer tube bead glass is attached together with the outer tube bead glass by the outer tube glass tube to form the other outer tube sealing end portion. Characteristic 2
Manufacturing method of double tube fluorescent lamp.