JP5332555B2 - Method for manufacturing double tube fluorescent lamp and double tube fluorescent lamp - Google Patents

Description

  The present invention relates to a method of manufacturing a double tube fluorescent lamp used for a light source of a general lighting device, a light source of a backlight device, and a light source of an ultraviolet irradiation device, and a double tube fluorescent lamp.

  Conventionally, a light source used in a backlight device such as a liquid crystal display device is formed on the outer surface of a discharge vessel, in which a rare gas is enclosed in a discharge vessel made of an elongated glass tube and a phosphor is applied on the inner surface. An external electrode type fluorescent lamp is known in which a voltage is applied to the pair of strip-shaped external electrodes to generate excimer discharge in a discharge vessel, and phosphors are excited with ultraviolet rays to obtain visible light.

In recent years, with regard to general lighting devices and backlight devices, it has been desired to further increase the light output. Using a conventionally known double-tube structure excimer lamp, the entire inner surface of the discharge vessel is fluorescent. A double-tube fluorescent lamp with a coated body has been developed.
This double tube type fluorescent lamp has a structure having a phosphor on the inner surface of the outer tube and the outer surface of the inner tube, so that it is fluorescent compared with a conventional cylindrical single tube type external electrode type fluorescent lamp. The body formation area increases and the light output increases.

In addition, a double tube fluorescent lamp in which a phosphor is applied to the entire inner surface of a discharge vessel has also been developed for an ultraviolet irradiation device. This double-tube fluorescent lamp emits ultraviolet rays using a phosphor that emits ultraviolet light such as 311 nm or 340 nm, for example, using excitation light of 172 nm ultraviolet light, for example.
For such an ultraviolet irradiation device, further enhancement of light output has been desired.

FIG. 5 is an explanatory diagram of a double tube fluorescent lamp.
In this double tube fluorescent lamp 10, a cylindrical outer tube 12 and a cylindrical inner tube 13 made of silica glass are coaxially arranged, and melted and joined at both ends to be joined to the outer tube 12. A discharge vessel 11 having a double tube structure in which a cylindrical discharge space S is formed between the inner tube 13 and a mesh-like external electrode 16 made of a conductive material such as a wire mesh is provided on the outer tube 12. An inner electrode 15 made of, for example, aluminum is provided in close contact with the inner surface of the inner tube 13, and a rare gas such as xenon gas is enclosed in the discharge space S. The phosphor 17 is provided on the inner surface of the outer tube 12 and the outer surface of the inner tube 13.
In the figure, reference numerals 18 and 19 denote exhaust pipe remaining portions formed at both ends of the discharge vessel 11.
JP 2001-023578 A

The process of providing the phosphor in the discharge vessel 11 of the double tube fluorescent lamp 10 is as follows.
As shown in FIG. 6A, the outer tube 12 and the inner tube 13 are sealed at both ends to form the discharge vessel 11, and connected to the discharge space S composed of a part of the outer tube 12 and the inner tube 13. A structure having the exhaust pipes 18a and 19a is manufactured.

  As shown in FIG. 6B, the discharge vessel 11 is erected so that the exhaust pipes 18a and 19a face in the vertical direction, and the lower phosphor pipe 19a is used as a phosphor for this structure. The fluorescent material 17a is sucked up by sucking the gas in the discharge vessel 11 from the upper exhaust pipe 18a, and the discharge vessel 11 is filled with the fluorescent material 17a.

  Thereafter, the suction of the gas in the discharge vessel 11 is stopped, whereby the phosphor material 17a sucked up in the discharge vessel 11 flows downward, and the phosphor material on the inner surface of the outer tube 12 and the outer surface of the inner tube 13. Will be applied.

  Then, as shown in FIG. 6 (c), in a state where the discharge vessel 11 is set up so that the exhaust pipes 18a, 19a face the vertical direction, a dry nitrogen gas is flowed from the upper exhaust pipe 18a, The phosphor 17 is discharged from the lower exhaust pipe 19a, and the phosphor raw material 17a is dried to form the phosphor 17 on the inner surface of the outer tube 12 and the outer surface of the inner tube 13.

However, in such a method, the nitrogen gas flowing into the discharge vessel 11 flows linearly from the upper exhaust pipe 18a toward the lower exhaust pipe 19a as shown by the arrow in FIG. 6 (c). It is.
As a result, the nitrogen gas flows favorably in the discharge space S1 formed along the arrow, but does not flow into the discharge space S2 formed away from the arrow, or is small even if it flows. .
Thus, the nitrogen gas does not flow uniformly and uniformly in the discharge vessel 11, and in the region where the nitrogen gas flows well, the phosphor raw material 17a can be quickly dried to obtain a phosphor having a predetermined thickness. In the region where the nitrogen gas is difficult to flow, the phosphor raw material 17a flows down before drying, resulting in a phosphor thinner than a predetermined thickness.

  That is, the phosphor 17 formed on the inner surface of the outer tube 12 and the outer surface of the inner tube 13 has a non-uniform thickness, and light is emitted in the tube axis direction of the double tube fluorescent lamp 10 and in the circumferential direction with respect to the tube axis. There was a problem that the output became non-uniform.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a method for manufacturing a double-tube fluorescent lamp in which the light output is uniform in the tube axis direction and the circumferential direction with respect to the tube axis, and The object is to provide a double-tube fluorescent lamp.

Method of manufacturing a double tube fluorescent lamp of claim 1 has a discharge vessel of a cylindrical double pipe structure according to the outer tube and the inner tube, the outer surface of the inner tube and the inner surface of said outer tube In the method of manufacturing a double-tube fluorescent lamp having a fluorescent material in the outer tube and the inner tube, a step of forming a protrusion toward the inner space of the discharge vessel in at least one of the outer tube and the inner tube; Forming a discharge vessel and providing an exhaust pipe, a step of pouring a phosphor material as a phosphor from the exhaust pipe into the discharge vessel, and the one exhaust pipe to the other exhaust pipe. Flowing the gas toward the surface, changing the direction in which the gas collides with the protrusion and flowing, and drying the phosphor material, and sealing off each of the exhaust pipes. To do.

Double tube type fluorescent lamp according to claim 2 has a discharge vessel of a cylindrical double pipe structure according to the outer tube and the inner tube, the phosphor on the inner surface and the outer surface of the inner tube of said outer tube A rare gas is sealed in a cylindrical discharge vessel formed between the outer tube and the inner tube, and electrodes are disposed on the outer surface of the outer tube and the inner surface of the inner tube, respectively. A double-tube fluorescent lamp having a discharge tube remaining portion in which the exhaust tube is cut off at both ends of the discharge vessel, and at least one of the outer tube and the inner tube is provided with a discharge vessel A protrusion is formed toward the internal space, and the protrusion is formed at a position where a gas for drying the phosphor raw material for forming the phosphor collides, and the tip of the protrusion and the outer tube Between the inner surface or between the tip of the protrusion and the inner tube Between the surface, characterized in that the air gap is formed.

  The double-tube fluorescent lamp according to claim 3 is the double-tube fluorescent lamp according to claim 2, and in particular, the protrusion is along the tube axis in the longitudinal direction of the discharge vessel. A plurality is formed.

According to the method for manufacturing a double tube fluorescent lamp of the present invention, the phosphor can be formed with a uniform thickness on the inner surface of the outer tube and the outer surface of the inner tube.
Furthermore, according to the double tube fluorescent lamp of the present invention, the light output can be made uniform in the tube axis direction and the circumferential direction with respect to the tube axis.

The double tube fluorescent lamp of the present invention will be described below with reference to the drawings.
FIG. 1 is an explanatory diagram of a double tube fluorescent lamp of the present invention.
In this double tube fluorescent lamp 10, a cylindrical outer tube 12 and a cylindrical inner tube 13 made of silica glass are coaxially arranged, and melted and joined at both ends to be joined to the outer tube 12. A discharge vessel 11 having a double tube structure in which a cylindrical discharge space S is formed between the inner tube 13 and a mesh-like external electrode 16 made of a conductive material such as a wire mesh is provided on the outer tube 12. The inner electrode 15 made of, for example, aluminum is provided in close contact with the inner surface of the inner tube 13, and a rare gas such as xenon gas is provided in the discharge space S of the discharge vessel 11. The phosphor 17 is provided on the inner surface of the outer tube 12 and the outer surface of the inner tube 13.

In this double tube fluorescent lamp 10, exhaust pipe remaining portions 18 and 19 are formed at both ends of the discharge vessel 11, respectively, and the exhaust tube is cut off. The inner tube 13 has a discharge space S in the discharge vessel 11. A protrusion 20 is formed toward a certain internal space.
The tip of the projection 20 is not in contact with the inner surface of the outer tube 12, and a gap is formed between the tip of the projection 20 and the inner surface of the outer tube 12.

Next, the manufacturing method of the discharge vessel of the double tube fluorescent lamp of the present invention will be described.
As shown in FIG. 2A, a projection 20 is formed by welding a columnar body made of silica glass to the inner tube 13 among the outer tube 12 and the inner tube 13 constituting the discharge vessel 11. The protrusion 20 is provided on the inner tube 13 so as to protrude toward the internal space of the discharge vessel 11.

  Next, as shown in FIG. 2B, the outer tube 12 and the inner tube 12 are sealed at both ends to form the discharge vessel 11, and the outer tube 12 and the inner tube 13 are formed at both ends of the discharge vessel 11. Exhaust pipes 18a and 19a connected to a part of the discharge space S are provided to manufacture a discharge vessel structure.

  As shown in FIG. 2 (c), the discharge vessel structure is constructed such that the discharge vessel 11 is set up so that the exhaust pipes 18a and 19a face in the vertical direction, and the lower exhaust pipe 19a is used as a phosphor. By sinking in the raw material 17a and sucking the gas in the discharge vessel 11 from the upper exhaust pipe 18a, the phosphor raw material 17a is sucked up, the phosphor raw material 17a is poured into the discharge vessel 11, and the inside of the discharge vessel 11 is fluorescent. Fill with body material 17a.

  Thereafter, the suction of the gas in the discharge vessel 11 is stopped, whereby the phosphor material 17a sucked up in the discharge vessel 11 flows downward, and the phosphor material on the inner surface of the outer tube 12 and the outer surface of the inner tube 13. Will be applied.

  Furthermore, as shown in FIG. 2 (d), in a state where the discharge vessel 11 is set up so that the exhaust pipes 18a and 19a face in the vertical direction, a nitrogen gas, which is a dried gas, is caused to flow from the upper exhaust pipe 18a. Nitrogen gas is discharged from the lower exhaust pipe 19a, and the phosphor raw material 17a is dried to form the phosphor 17 on the inner surface of the outer tube 12 and the outer surface of the inner tube 13.

  Then, as shown in FIG. 2 (e), one exhaust pipe 18a is cut off, the gas in the discharge vessel 11 is exhausted from the other sealing pipe 19a, and xenon gas, which is a rare gas, is exhausted after the exhaust process is completed. An appropriate amount is sealed in the discharge vessel 11, the sealing tube 19a is sealed, and the discharge vessel is completed.

In the above process, the step of directly applying the phosphor raw material 17a to the inner surface of the outer tube 12 and the outer surface of the inner tube 13 has been described, but before applying the phosphor raw material 17a, You may add the process of apply | coating and drying the liquid glass film constituent raw material for forming a glass film on the surface and the outer surface of the inner tube 13.
Further, the outer tube 12 and the inner tube 13 constituting the discharge vessel 11 are not limited to silica glass, but use glass such as borosilicate glass or aluminosilicate glass as hard glass, and soda lime glass as soft glass depending on applications. It is also possible to do.
This step is the same as the steps shown in FIGS. 2C and 2D, and uses a glass film constituting material instead of the phosphor material 17a.

As shown in FIG. 2 (d), in the step of drying the phosphor raw material 17a, the nitrogen gas flowing into the discharge vessel 11 flows into the discharge vessel 11 from the upper exhaust pipe 18a as indicated by an arrow. Flows into the discharge space S1. Then, the nitrogen gas travels through the discharge space S1, collides with the protrusion 20, and part of the gas also flows into the discharge space S2.
In other words, the protrusion 20 allows the nitrogen gas to flow uniformly and evenly in the discharge vessel 11, and the phosphor raw material 17a is dried at substantially the same speed at any position, so that the thickness of the phosphor is uniform. be able to.

  According to the double tube fluorescent lamp completed by such a manufacturing method, the phosphors 17 formed on the inner surface of the outer tube 12 and the outer surface of the inner tube 13 have a uniform thickness as a whole, and the double tube The light output is uniform in the tube axis direction of the fluorescent lamp 10 and in the circumferential direction with respect to the tube axis.

FIG. 3 is an explanatory view of another embodiment of the double tube fluorescent lamp of the present invention.
In this embodiment, the protruding portion 21 formed on the inner tube 13 is formed by heating and melting the inner tube 13 so as to protrude toward the inner space of the discharge vessel 11.
The tip of the projection 21 is not in contact with the inner surface of the outer tube 12, and a gap is formed between the tip of the projection 21 and the inner surface of the outer tube 12, and gas flows.

  Also in this embodiment, in the step of drying the phosphor material, the nitrogen gas flowing into the discharge vessel 11 flows into the discharge vessel 11 from the exhaust pipe shown as the exhaust pipe remaining portion 18, and first, into the discharge space S1. Flows in. Then, the nitrogen gas travels through the discharge space S1, collides with the protrusion 21, and part of the gas also flows into the discharge space S2, so that the nitrogen gas flows uniformly and evenly in the discharge vessel 11. The phosphor material can be dried at substantially the same speed at any position to make the thickness of the phosphor 17 uniform.

  According to such a double tube fluorescent lamp, the phosphors 17 formed on the inner surface of the outer tube 12 and the outer surface of the inner tube 13 have a uniform thickness as a whole. The light output is uniform in the tube axis direction and in the circumferential direction with respect to the tube axis.

Then, as in the double tube fluorescent lamp shown in FIG. 3, a plurality of protrusions 21 are formed along the tube axis in the longitudinal direction of the discharge vessel 11, whereby the flow of nitrogen gas flowing into the discharge vessel 11. Can be made even more random, the nitrogen gas flowing into the discharge vessel 11 can flow more uniformly, and the thickness of the phosphor can be made uniform with certainty.
As a result, the light output is more uniform in the tube axis direction of the double tube fluorescent lamp 10 and in the circumferential direction with respect to the tube axis.

  In the above embodiment, an example in which the protrusion is formed on the inner tube is shown, but the protrusion may be formed on the outer tube toward the inner space of the discharge vessel, and the inner portion of the discharge vessel is formed on both the inner tube and the outer tube. A protrusion may be formed toward the space.

FIG. 4 is an explanatory diagram of another embodiment of the double tube fluorescent lamp of the present invention.
In this embodiment, the right end of the inner tube 13 in the drawing is joined to the end of the outer tube 12, and the left end of the inner tube 13 in the drawing is sealed only by the inner tube 13, and the outer tube is sealed. 12 is sealed with only the outer tube 12 to form a discharge vessel 11.
Further, a columnar body made of silica glass is welded to the outer tube 12 to form the protruding portion 20. The protrusion 20 is provided on the outer tube 12 so as to protrude toward the inner space of the discharge vessel 11.
The tip of the projection 20 is not in contact with the inner surface of the inner tube 13, and a gap is formed between the tip of the projection 20 and the inner surface of the inner tube 13 so that gas flows.

  Also in this embodiment, nitrogen gas flows into the discharge spaces S1, S2. The nitrogen gas that has flowed into the discharge spaces S1 and S2 collides with the protrusions 20 and part of the gas also flows into the discharge space on the opposite side. In the step of drying the phosphor material, The nitrogen gas flowing into the container 11 flows evenly from the exhaust pipe shown as the exhaust pipe remainder 18 into the discharge container 11, and the phosphor material is dried at almost the same speed at any position, and the fluorescent material is dried. The thickness of the body 17 can be made uniform.

  According to such a double tube fluorescent lamp, the phosphors 17 formed on the inner surface of the outer tube 12 and the outer surface of the inner tube 13 have a uniform thickness as a whole. The light output is uniform in the tube axis direction and in the circumferential direction with respect to the tube axis.

Then, as in the double tube fluorescent lamp shown in FIG. 4, the plurality of protrusions 20 are formed along the tube axis in the longitudinal direction of the discharge vessel 11, whereby the flow of nitrogen gas flowing into the discharge vessel 11. Can be made even more random, the nitrogen gas flowing into the discharge vessel 11 can flow more uniformly, and the thickness of the phosphor can be made uniform with certainty.
As a result, the light output is more uniform in the tube axis direction of the double tube fluorescent lamp 10 and in the circumferential direction with respect to the tube axis.

It is explanatory drawing of the double tube | pipe type fluorescent lamp of this invention. It is explanatory drawing of the manufacturing process of the double tube | pipe type fluorescent lamp of this invention. It is explanatory drawing of the double tube | pipe type fluorescent lamp of the other Example of this invention. It is explanatory drawing of the double tube | pipe type fluorescent lamp of the other Example of this invention. It is explanatory drawing of the conventional double tube | pipe type fluorescent lamp. It is manufacturing process explanatory drawing of the conventional double tube | pipe type fluorescent lamp.

Explanation of symbols

11 Discharge vessel 12 Outer tube 13 Inner tube 15 Electrode 16 Electrode 17 Phosphor 18 Remaining exhaust pipe 19 Remaining exhaust pipe 20 Protrusion 21 Protrusion

Claims (3)

In a manufacturing method of a double tube fluorescent lamp having a discharge vessel of a cylindrical double tube structure with an outer tube and an inner tube, and having a phosphor on the inner surface of the outer tube and the outer surface of the inner tube,
Forming a protrusion on at least one of the outer tube and the inner tube toward the internal space of the discharge vessel;
Forming a discharge vessel with the outer tube and the inner tube, and providing an exhaust tube;
Pouring a phosphor raw material to be a phosphor from the exhaust pipe into the discharge vessel;
Flowing a gas from the one exhaust pipe toward the other exhaust pipe, changing the direction in which the gas collides with the protrusion and flows, and drying the phosphor material;
Sealing off each of the exhaust pipes;
A method for producing a double-tube fluorescent lamp, comprising: A discharge vessel having a cylindrical double-tube structure composed of an outer tube and an inner tube; a phosphor is provided on the inner surface of the outer tube and the outer surface of the inner tube; and between the outer tube and the inner tube A double tube fluorescent lamp in which a rare gas is enclosed in a cylindrical discharge vessel formed on the electrode, and electrodes are respectively disposed on the outer surface of the outer tube and the inner surface of the inner tube,
Exhaust pipe remainders are formed by sealing off the exhaust pipe at both ends of the discharge vessel,
At least one of the outer tube and the inner tube is formed with a protrusion toward the inner space of the discharge vessel,
The protrusion is formed at a position where a gas for drying the phosphor material at the time of forming the phosphor collides,
A space is formed between the tip of the projection and the inner surface of the outer tube, or between the tip of the projection and the inner surface of the inner tube. Double tube fluorescent lamp.   The double tube fluorescent lamp according to claim 2, wherein a plurality of the protrusions are formed along a tube axis in a longitudinal direction of the discharge vessel.

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