JP2004063284A - Luminescent bulb for electrodeless lamp, electrodeless lamp and manufacturing method of luminescent bulb for electrodeless lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a luminescent bulb for an electrodeless lamp capable of preventing adhesion of slurries on a protection layer at a part where an inner tube and an outer tube are to be sealed. <P>SOLUTION: The luminescent bulb is provided with an outer tube having an opening and an inner tube of a shape of a bottomed cylinder, and an end part of the inner tube at an opening side is sealed to an extended part 18 of the outer tube 16 in a state in which the inner tube is insertion-coupled from the opening of the outer tube 16 down to the bottom of the inner tube. The outer tube 16 has a storage part 19 formed extended outside from the vicinity of a sealing part 13. The formation of the protection layer on the inside face of the outer tube 16 is carried out through a process of applying the slurries 41 of the protection layer on the inside face with the opening directed upward, a process of absorbing and draining the slurries 41 after the application with the upward direction kept, and a process of drying while storing the slurries 41 dripping down at the storage part 19 with the opening of the outer tube 16 directed downward. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-emitting bulb for an electrodeless lamp having a protective layer formed on the inner surface of an outer tube, an electrodeless lamp provided with the light-emitting bulb, and a method of manufacturing a light-emitting bulb for an electrodeless lamp. About.
[0002]
[Prior art]
Since the electrodeless fluorescent lamp does not have a filament and an electrode that determine the life of the general fluorescent lamp, it has a longer life characteristic than the general fluorescent lamp. This electrodeless fluorescent lamp (hereinafter simply referred to as “electrodeless lamp”) has, for example, a glass light-emitting bulb having a cylindrical concave portion and an excitation coil buried in the concave portion. When an AC magnetic field is generated in the light-emitting bulb by passing an alternating current of the same, a gas plasma of an inert gas and mercury sealed in the light-emitting bulb is formed. The layer is excited to generate visible light.
[0003]
The light emitting bulb includes an outer tube including a spherical container having an opening, an extending portion extending outward from the opening, and a bottomed cylindrical inner tube for forming the recess. The end on the opening side of the inner tube is sealed to the extending portion of the outer tube. Thereby, a sealed discharge space is formed between the outer tube and the inner tube.
A glass material is used for the container portion as described above, and a protective layer is formed between the inner surface of the container portion and the fluorescent layer in order to prevent sodium from being eluted from the glass material during lighting. . The reason for preventing the elution of sodium is that when the sodium elutes, it combines with mercury in the light emitting bulb to form amalgam, and the amount of mercury in the discharge space decreases, thereby reducing the luminous flux.
[0004]
FIG. 3 is a view for explaining a conventional method for forming a protective layer on the inner surface of an outer tube.
First, with the opening 57a of the extending portion 57 of the outer tube 52 facing upward, as shown in FIG. 3A, the outflow nozzle 60 for flowing out the suspension 61 for the protective layer is moved in the X direction. Then, the tip is inserted from the opening 57a of the extension portion 57 to a predetermined position in the outer tube 57.
[0005]
The outflow nozzle 60 allows the suspension 61 to flow downward from the tip. Then, the suspension 61 flows out from the outflow nozzle 60 until the suspension 61 in the outer tube 57 reaches a predetermined position. Thus, the suspension 61 is applied to a predetermined range of the container portion 56, for example, the entire inner surface. The suspension 61 is composed of alumina particles and pure water.
[0006]
Next, as shown in FIG. 3B, the outer tube 52 is inclined, and the suspension 61 is discharged from the opening 57a of the extending portion 57. When the suspension is completed, the opening 57a of the extending portion 57 is closed. The outer tube 52 is turned upside down. Then, in this state, the drying nozzle 62 is inserted into the outer tube 52 from below. The drying nozzle 62 blows hot air from the tip thereof, and the suspension 61 in the outer tube 52 is dried by the hot air.
[0007]
Finally, when the suspension 61 is discharged and the suspension 61 is dried, the protective layer (alumina particles) adhered to the inner surface of the extending portion 57 is, for example, as shown in FIG. The cleaning is performed by the ultrasonic cleaning device 63. That is, the alumina particles are washed and removed by using ultrasonic vibration in a state where the stretched portion having the alumina particles adhered to the inner surface is immersed in the cleaning liquid 65 in the cleaning tank 64. The removal of the alumina particles is not easy even if the extended portion 57 is wiped or washed with water because the particles are very fine, and the ultrasonic cleaning device 63 is used.
[0008]
When the washing and removal are completed, the suspension 61 is dried again to form a fluorescent layer on the formed protective layer, and thereafter, the extending portion 57 of the outer tube 52 and the end of the inner tube are sealed. . When the extending portion 57 of the outer tube 52 is directed upward when the suspension 61 is dried, the suspension 61 accumulates at the head (end opposite to the extending portion 57) of the outer tube 52, The formed protective layer becomes thicker, and the transmittance of visible light deteriorates.
[0009]
Further, the reason why the protective layer (alumina particles) attached to the inner surface of the extending portion 57 is removed is that when the glass material is melted by the heat at the time of sealing with the inner tube and the alumina particles enter the glass material, This is because the inert gas in the light emitting bulb leaks (leaks) when the lamp is turned on.
[0010]
[Problems to be solved by the invention]
In the conventional method of manufacturing a light emitting bulb, there is a problem that productivity is poor because a step of removing alumina particles attached to the extending portion 57 is always required.
When the ultrasonic cleaning device 63 is used for removing the alumina particles, the alumina particles removed from the extending portion 57 are scattered in the cleaning liquid 65. Although the cleaning liquid 65 is circulated and filtered to recover the alumina particles in the liquid, the alumina particles cannot be completely removed from the extending section 57 as long as the extending section 57 is immersed in the cleaning liquid 65. For this reason, there is a problem that the reliability of the sealing portion is reduced.
[0011]
The present invention has been made in view of the above-described problems, and has been made for an electrodeless lamp that can prevent a suspension for a protective layer from adhering to a portion to be sealed between an inner tube and an outer tube. An object of the present invention is to provide a method for manufacturing a light emitting bulb, a light emitting bulb used in the method for manufacturing the same, and an electrodeless lamp including the light emitting bulb manufactured by the method for manufacturing the same.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, a light-emitting bulb according to the present invention has an outer tube having an opening and a protective layer formed on an inner surface, which is sealed to a peripheral portion of the opening in a state where the inner tube is inserted. A light-emitting bulb for an electrodeless lamp, wherein the outer tube has a dripping protection liquid reservoir near the sealing portion and on the protective layer side.
[0013]
According to this, for example, when the protective liquid applied to the inner surface of the outer tube is dried, even if the opening of the outer tube is turned downward, the protective liquid drooping along the inner surface of the outer tube can be stored in the reservoir. it can. For this reason, it is possible to prevent the protection liquid from flowing into the portion to be sealed with the inner tube.
Further, the outer tube has a substantially axially symmetric shape, and is characterized in that one end in the axial direction is open. For this reason, for example, when the protective liquid is applied or dried, the outer tube is rotated around its axis, thereby reducing the variation in the thickness of the protective liquid in the outer tube.
[0014]
Furthermore, a part of the drooping protection liquid reservoir is characterized by extending outward from the vicinity of the sealing portion, and in particular, the drooping protection liquid reservoir is formed in a direction substantially perpendicular to the axis. It is characterized by having a substantially flat portion. According to this, for example, the amount of the protection liquid stored in the storage unit can be increased. Therefore, it is possible to more reliably prevent the protection liquid from flowing into the portion to be sealed with the inner tube.
[0015]
In addition, a fluorescent layer is formed on the inner layer of the protective layer. In particular, a fluorescent layer is also formed on the inner surface of the drooping protection liquid reservoir, and the thickness of the fluorescent layer is larger than that of the fluorescent layer formed in other portions. For this reason, the luminous flux at the time of light emission can be increased.
Further, a light-emitting bulb according to any one of claims 1 to 6 is provided. For this reason, since there is a light-emitting bulb that can be manufactured efficiently, an electrodeless lamp that can be manufactured efficiently can be obtained as a whole.
[0016]
In particular, the electrodeless lamp includes a holding member that holds the light emitting bulb, and a cover that covers the outer surface of the dripping protective liquid reservoir of the arc tube bulb held by the holding member so as to be invisible. It is characterized by: By increasing the thickness of the fluorescent layer on the inner surface of the reservoir, the amount of visible light increases. On the other hand, since the reservoir is covered with the cover, there is no problem even if the amount of visible light transmitted through the fluorescent layer decreases.
[0017]
Further, in a method for manufacturing a light-emitting bulb for an electrodeless lamp, the inner tube is inserted into an outer tube having an opening and a protective layer is formed on the inner surface, and the inner tube is sealed to a peripheral portion of the opening. In the outer tube, a reservoir is formed in the vicinity of the sealing portion and on the side where the protective layer is to be formed, and a reservoir is formed on the inner surface of the outer tube. Applying the suspension for the protective layer to the, and applying the suspension while suspending the suspension hanging down the inner surface of the outer tube with the opening of the outer tube facing downward in the storage portion. And a drying step.
[0018]
According to this, for example, when drying the suspension applied to the inner surface of the outer tube, even if the opening of the outer tube is directed downward, the suspension hanging down along the inner surface of the outer tube is stored in the storage portion. Can be. Therefore, it is possible to prevent the suspension from flowing into the portion to be sealed with the inner tube.
Furthermore, a step is provided between the application step and the drying step, in which the suspension after application is sucked and discharged with the opening facing upward. For this reason, the suspension in the outer tube can be discharged without causing the suspension in the outer tube to adhere to the portion to be sealed with the inner tube.
[0019]
Further, the drying step is performed while rotating the outer tube around the tube axis, and the upside down of the outer tube is performed while rotating the outer tube around the tube axis. It is characterized by: For this reason, variation in the thickness of the suspension on the inner surface of the outer tube can be reduced.
In addition, the application and discharge of the suspension are performed by a nozzle having a function of ejecting the suspension and a function of sucking and discharging the suspension. Therefore, the application and discharge of the suspension can be performed efficiently.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of an electrodeless fluorescent lamp according to the present invention will be described with reference to the drawings.
1. Configuration of electrodeless fluorescent lamp
FIG. 1 is a front view showing the entire structure of the electrodeless fluorescent lamp according to the present invention, in which a part is cut away. The electrodeless fluorescent lamp (hereinafter simply referred to as "electrodeless lamp") 10 utilizes a so-called electromagnetic induction coupling type discharge (H discharge).
[0021]
The electrodeless lamp 10 has a light emitting bulb 12 made of translucent glass. Mercury (Hg) and an inert gas, for example, a krypton (Kr) gas, are sealed in a discharge space 34 in the light emitting bulb 12 as a discharge substance.
The light-emitting bulb 12 has a bottomed cylindrical recess 14 in which an excitation coil unit 20 is embedded. The excitation coil unit 20 includes a core 21 and an excitation coil 22 turned around the core 21. The light emitting bulb 12 will be described later in detail.
[0022]
A circular extension 26 of a heat sink 25 made of aluminum is inserted on the inner peripheral side of the excitation coil unit 20 as a heat radiation means for preventing a temperature rise of the core 21 when a current flows through the excitation coil 22. . The heat sink 25 has a cup-shaped portion 27 extending from the circular extending portion 26, and the cup-shaped portion 27 is fixed to a case 28 made of synthetic resin.
[0023]
A high-frequency drive circuit 30 connected to the excitation coil 22 for flowing a high-frequency alternating current through the excitation coil 22 is housed in the case 28. A base 31 having the same standard as that of a general incandescent lamp is attached to the case 28, and electric power from a commercial power supply is supplied to the high-frequency drive circuit 30 via the base 31.
The light-emitting bulb 12 has, for example, the shape of a light-emitting bulb used in a general incandescent light bulb or a bulb-shaped fluorescent lamp, for example, an A-shape. And an inner tube 15. The outer tube 16 includes a spherical container 17 having an opening 17a,
A tubular extension 18 extending outward from the peripheral edge of the opening 17a in the direction of the tube axis A of the outer tube 16; The opening 17a of the container 17 is provided on one end side of the container 17 in the direction of the tube axis A.
[0024]
The inner tube 15 has a cylindrical shape with a bottom so that the excitation coil unit 20 can be housed therein, and an end opposite to the bottom is sealed to the extending portion 18 of the outer tube 16. As a result, a sealed discharge space 34 is formed between the inner tube 15 and the outer tube 16. On the inner surface of the light emitting bulb 12, that is, on the inner surface of the outer tube 16 and the outer surface of the inner tube 15, a protective layer described in the related art is formed, and a fluorescent layer is formed on this protective layer. The protective layer is formed by applying a suspension for the protective layer to the inner surface of the light emitting bulb 12 and drying the applied suspension.
[0025]
As will be described later with reference to a manufacturing method, the outer tube 16 is formed with a reservoir 19 extending outward from the vicinity of the sealing portion 13 in the discharge space 34 in a direction orthogonal to the tube axis A. The reservoir 19 is formed over the entire periphery of the opening 17 a of the container 17, and is flattened in a direction perpendicular to the tube axis A (hereinafter, simply referred to as “flat portion 19 a”). )have.
[0026]
The reason why the sealing portion 13 for sealing the outer tube 16 and the inner tube 15 is separated from the peripheral edge of the opening 17a of the container portion 17 as shown in FIG. Is transmitted to the reservoir 19 to prevent the fluorescent layer formed on the inner surface of the reservoir 19 from wrinkling or, in severe cases, from peeling off the fluorescent layer.
2. About the manufacturing method of the light emitting bulb
An outer tube 16 for a light emitting bulb having the above configuration is prepared. The outer tube 16 is before being sealed to the inner tube, and the extending portion 18 extends long in the direction of the tube axis A as shown in FIG. The length of the extending portion 18 may be longer than the distance from the end of the container portion 17 on the opening 17a side to the portion to be sealed with the inner tube 15 (the sealing portion 13 in FIG. 1). However, in the present embodiment, since the outer tube 16 is rotated or inverted, the outer tube 16 is long enough to hold the extending portion 18 at that time.
[0027]
Now, a method for manufacturing a light emitting bulb, particularly a method for forming a protective layer on the inner surface of the outer tube 16 will be described. First, the outer tube 16 is arranged such that the opening 18a of the extending portion 18 is on the upper side, and the coating nozzle 40 is moved in the X direction, and the coating nozzle 40 is inserted into the outer tube 16 from the opening 18a of the extending portion 18. Then, the suspension is applied and discharged.
Here, the application nozzle 40 will be described. The application nozzle 40 has a liquid ejection unit 40a that ejects the suspension 41 from the lower end thereof, and a liquid suction unit 40b that sucks and discharges the suspension 41 from the lower end thereof. In the present embodiment, the application nozzle 40 has a double-pipe structure. For example, the suspension is sucked and discharged through an inner tube, and the suspension is ejected through an outer tube. . The liquid ejecting unit 40a ejects the suspension 41 from a position separated from the tip of the liquid suction unit 40b by a predetermined distance upward.
[0028]
The distance between the lower end of the liquid suction unit 40b and the lower end of the liquid ejection unit 40a is substantially equal to the distance between the upper limit position of the application range where the suspension 41 is to be applied in the container 17 and the bottom of the container 17. That is, when the front end (lower end) of the liquid suction unit 40b reaches the bottom of the container 17, the suspension 41 ejected from the liquid ejection unit 40a just reaches the upper limit position where the suspension 41 is applied. Has become.
[0029]
In addition, the liquid ejection part 40a ejects the suspension 41 from the lower end in four directions (for example, four directions at 90 ° intervals) when viewed from the axis A direction of the nozzle (in plan view). Further, the direction in which the suspension 41 is jetted is a direction substantially orthogonal to the axis of the nozzle.
As shown in FIG. 2A, the application nozzle 40 having such a configuration is inserted into the outer tube 16 such that the tip of the liquid suction part 40 b reaches the bottom of the container part 17, The suspension 41 is ejected from 40a.
[0030]
At this time, the outer tube 16 is rotated around its tube axis A in the Y direction. The reason for rotating the outer tube 16 is to apply the suspension 41 to the inner surface of the container 17 so as to be substantially uniform. The suspension 41 is composed of alumina particles and pure water, as in the prior art, and has a viscosity similar to that of pure water.
Next, when the application of the suspension 41 to the inner surface of the container portion 17 by jetting is completed, as shown in FIG. 2B, the outer tube 16 is kept as it is (with the extending portion 18 facing upward). Then, the suspension 41 accumulated in the container section 17 is sucked and discharged from the liquid suction section 40. The discharged suspension 41 is collected in a tank through a filter (not shown). The recovered suspension 41 is sent out again from the tank to the liquid ejection part 40a.
[0031]
As described above, since the suspension 41 ejected from the liquid ejection unit 40a and accumulated in the outer tube 16 is discharged through the liquid suction unit 40b, the suspension 41 is discharged as in the related art. It does not adhere to the extending portion 18 at the time of discharge. Further, since the application nozzle 40 can eject and discharge the suspension 41, the suspension 41 can be continuously collected after the ejection of the suspension 41, so that the application can be performed efficiently.
[0032]
Next, when the suspension 41 is discharged from the outer tube 16, as shown in FIG. 2C, the outer tube 16 is rotated around the tube axis A in the Y direction while the extending portion 18 is simultaneously lowered. And turn it around Z direction (direction perpendicular to the tube axis A) to turn it upside down. Then, in a state where the extending portion 18 is down, the outer tube 16 is rotated around the tube axis A in the Y direction while hot air is blown from the outside of the outer tube 16 as shown in FIG. Then, the suspension 41 in the container section 17 is dried. Thereby, a protective layer is formed on the inner surface of the outer tube 16. During the drying of the suspension 41, the suction nozzle 42 is inserted into the outer tube 16 to suck and exhaust the vapor generated from the suspension 41.
[0033]
In addition, since the outer tube 16 is turned upside down before drying while rotating the outer tube 16 around the tube axis A, the suspension 41 remaining in the container portion 17 bottoms the inner surface at the time of inversion. Instead of flowing straight from the side to the opening 17a side, it flows evenly over a wide range.
Thereby, the thickness of the suspension 41 applied in the container 17 can be made substantially uniform. Further, since the outer tube 16 has a reservoir 19 as shown in FIG. 1, the suspension 41 hanging down from the bottom of the container portion 17 along the inner surface to the extending portion 18 is stored in the reservoir 19. , And does not flow (hang) into the extending portion 18 as in the related art.
[0034]
In addition, since the outer tube 16 is rotating around the tube axis A at a predetermined rotation speed, the suspension 41 in the container portion 17 stays on the inner surface above the opening 17a of the container portion 17 due to centrifugal force and moves downward. It is hard to flow to.
The outer tube 16 on which the protective layer is formed as described above has a fluorescent layer formed on the protective layer. Finally, with the inner tube inserted into the outer tube 16 so that the bottom of the inner tube 15 comes to the top from the opening 18a of the extending portion 18 of the outer tube 16, the extending portion 18 of the outer tube 16 is The light emitting bulb 12 is formed by sealing the end of the inner tube 15 opposite to the bottom at a predetermined position and cutting off an excess portion of the extension 18 of the outer tube 16. Although a description is omitted, a protective layer and a fluorescent layer are also formed on the outer periphery of the inner tube 15, and a rare gas, mercury, or the like is sealed in the light emitting bulb 12.
[0035]
In the above-described manufacturing process of the light-emitting bulb 12, particularly, in the process of forming the protective layer on the inner surface of the outer tube 16, the suspension in the outer tube 16 with the opening 18 a of the extending portion 18 of the outer tube 16 down. Although the outer tube 16 is dried, the outer tube 16 is formed with the reservoir 19 at the periphery of the opening 17 a of the container 17, so that the suspension 41 hanging down along the inner surface of the container 17 is formed. Is accumulated in the reservoir 19, and the suspension 41 for the protective layer flows (adheres) into the extending portion 18 of the outer tube 16 and particularly into a portion (to be sealed) to be sealed with the end of the inner tube 15. There is no.
[0036]
For this reason, the conventional step of removing the protective layer (alumina particles) attached to the stretching portion 18 is not required, and the productivity can be improved. In addition, since the suspension 41 for the protective layer does not adhere to the extending portion 18, there is no danger that the alumina particles may melt into the molten glass when sealing with the inner tube. Therefore, the reliability of the sealing portion 13 can be significantly improved.
[0037]
3. Lamp performance
In the electrodeless lamp 10 having the above-described configuration, a high-frequency excitation current flows from the high-frequency drive circuit 30 to the excitation coil 22, so that a plasma discharge is formed by the mercury sealed in the light emitting bulb 12 and the sealed gas (Hg + Kr). Due to this discharge, ultraviolet rays are emitted from the mercury, and the ultraviolet rays excite the fluorescent layer formed on the inner surface of the light emitting bulb 12 to generate visible light.
[0038]
As described above, the electrodeless lamp 10 having the reservoir 19 in the light-emitting bulb 12 and having the fluorescent layer formed on the inner surface thereof is more luminous when the lamp is turned on than the electrodeless lamp having no reservoir 19. The luminous flux is improved.
That is, in the step of forming the fluorescent layer, when the applied suspension for the fluorescent layer is dried, the drying is performed with the opening 18a of the extending portion 18 of the outer tube 16 down, so that the flat portion of the reservoir 19 is formed. The suspension accumulates on the inner surface of the portion 19a. As a result, the fluorescent layer formed on the inner surface of the reservoir 19 becomes thicker than the fluorescent layers at other portions. Thereby, the amount of visible light excited by ultraviolet rays can be increased.
[0039]
Also, when forming the fluorescent layer, the opening 18a of the extending portion 18 is set downward when drying after applying the suspension for the fluorescent layer so that the fluorescent layer at the head of the outer tube 16 is not thickened. I have. When the fluorescent layer on the head is thick, the transmittance of visible light at the head becomes poor, and when the electrodeless lamp 10 is turned on, the illuminance immediately below the lamp may decrease. Hereinafter, the difference in the luminous flux when the lamp is turned on depending on the presence or absence of the reservoir 19 in which the fluorescent layer is formed will be described. An electrodeless lamp having the same configuration as the electrodeless lamp and having a reservoir 19 formed in the light emitting bulb 12 (hereinafter referred to as "the invention") and a conventional lamp having no reservoir 19 formed therein ( Hereafter, the luminous flux at the time of lighting both of them was measured using “conventional product”).
[0040]
Here, the configurations of the invention product and the conventional product used for the measurement will be described.
The invention product and the conventional product have the same configuration, and the different part is the presence or absence of the above-mentioned reservoir 19. Therefore, both will be described with reference to FIG. 1 for convenience. The maximum outer diameter D of the light emitting bulb 12 in both cases is 65 mm, the total length L is 71 mm, and in FIG. 1, the thickness of the fluorescent layer at the position B is approximately 15 μm and the thickness at the position C is 18 μm. Both have substantially the same thickness. Further, in the product of the present invention, the thickness at the position E in FIG. 1 is 80 μm, whereas the thickness of the position of the conventional product (G in FIG. 23 μm. The width F of the flat portion 19a in the reservoir 19 of the invention is 8 mm. The other configurations, for example, the dimensions of the high-frequency drive circuit, the excitation coil, and the inner tube are the same.
[0041]
These invention products and conventional products were respectively lit with their bases facing upward. At this time, the luminous flux of both of them is about 760 lm for the invention product and about 710 lm for the conventional product, and the luminous flux of the invention product is increased by 50 lm (7%) with respect to the conventional product.
The light-emitting bulb of the lamp used for the measurement of the emitted light flux had a maximum outer diameter D of 65 mm, but in order to confirm whether or not the emitted light flux could be improved by changing the size of the light-emitting bulb, By changing the maximum outer diameter D of the light emitting bulb to 70 mm, a second invention product having a reservoir and a second conventional product having no reservoir are manufactured (other configurations are the same as those of the above invention and the conventional product). The same measurement of the emitted luminous flux was performed. As a result, it was confirmed that the second invention product was increased by 5% with respect to the second conventional product.
[0042]
From these results, a reservoir 19 is formed in the outer tube 16 irrespective of the size (maximum outer diameter) of the outer tube, and the thickness of the fluorescent layer formed in the flat portion 19a of the reservoir 19 is changed to another value. It is considered that the light emission luminous flux is improved by making it thicker than the part (for example, the above-mentioned B position and C position). In addition, by increasing the thickness of the fluorescent layer in the flat portion 19a, visible light generated from the inner surface of the reservoir 19 increases, but conversely, visible light transmitted through the reservoir 19 decreases. However, since the reservoir 19 is hidden in the case 28, there is no problem even if the amount of visible light transmitted through the reservoir 19 decreases.
[0043]
On the other hand, comparing the measurement results of the invention using the light emitting bulbs having different maximum outer diameters D of the outer tube 16 and the second invention, the maximum outer diameter D of the outer tube 16 is increased (from 65 mm to 70 mm). Then, the increase ratio (7% → 5%) of the luminous flux of each invention product to each conventional product is small.
In the above measurement, the size (area) of the flat portion 19a of the reservoir 19 is made constant and only the maximum outer diameter D of the outer tube 16 is increased. It is considered that the ratio of the size of 19a was reduced, and the increase ratio of the luminous flux was also reduced. Therefore, regardless of the diameter of the outer tube 16, if the area of the flat portion 19a is increased, it is considered that the luminous flux at the time of lighting increases.
[0044]
4. Other
1) Rotational speed of outer tube during drying
If the rotation speed of the outer tube 16 is high when the suspension 41 for the protective layer is dried, the suspension 41 may be centrifugally moved to substantially the center of the outer tube 16 in the tube axis A direction, that is, the outer tube 16 Gather at the portion where the outer diameter becomes maximum, and the protective layer at that portion becomes thicker. Conversely, when the rotation speed is low, the protective layer in the lower portion of the container 17 becomes thick.
[0045]
On the other hand, the thicker the protective layer, the more difficult the visible light generated when the lamp is turned on to pass. Usually, the lamp is often turned on with the base up, and it is preferable that the visible light emitted from the lamp be larger at the lower side of the light-emitting bulb (the side opposite to the base) because the illuminance immediately below the lamp increases. .
From this, it can be said that the rotation speed of the outer tube 16 is preferably such that the suspension 41 accumulates below the opening 17 a of the container 17. Note that the rotation speed of the outer tube 16 is determined by the viscosity of the suspension 41 for the protective layer, the drying temperature, and the like. In the present embodiment, an appropriate test is performed by performing a test in an actual process. The rotation speed is determined.
[0046]
2) Application nozzle
The application nozzle 40 in the above embodiment is configured to eject the suspension 41 in four directions, but is not limited to four directions. For example, even if it is ejected to only one side, the suspension 41 can be uniformly applied by adjusting the rotation speed and time of the outer tube 16. However, it goes without saying that the application of the suspension 41 can be performed more efficiently by ejecting the suspension 41 in a plurality of directions.
[0047]
Further, the application nozzle 40 may be one that simply causes the suspension 41 to flow into the outer tube 16. That is, when the suspension 41 of the protective layer is applied to the inner surface of the outer tube 16, the outer tube 16 is prevented from adhering to the portion to be sealed to the inner tube 15 (the sealing portion 13). It is sufficient that the suspension 41 can flow into the inside.
The application nozzle 40 has a function of ejecting the suspension 41 and sucking and discharging (recovering). For example, the ejection of the suspension 41 uses a dedicated ejection nozzle. A dedicated suction / discharge nozzle may be used for recovery. Also in this case, the suspension 41 can be applied and discharged without attaching the suspension 41 to a portion to be sealed to the inner tube 15, and after the suspension 41 is dried, a conventional stretching unit is used. The step of removing the protective layer (suspension) attached to 18 can be eliminated.
[0048]
(Modification)
As described above, the present invention has been described based on the embodiments. However, it goes without saying that the content of the present invention is not limited to the specific examples shown in the above embodiments. can do.
1. Light emitting bulb shape
In the above-described embodiment, the shape of the light emitting bulb is a shape, that is, an A shape. This is because, for example, it is assumed that it is used as a substitute for an existing incandescent lamp or a bulb-shaped fluorescent lamp. Therefore, even if the shape of the light emitting bulb is, for example, a G type, a D type, or a T type, it can be implemented in the same manner as in the above embodiment.
[0049]
2. About the shape of the reservoir
In the above embodiment, the reservoir has a flat portion formed in a direction substantially perpendicular to the tube axis of the outer tube, but may have another shape. In other words, as described in the above manufacturing method, the shape of the reservoir portion, when the opening of the outer tube is turned downward during the drying of the suspension, stores the suspension hanging down the inner surface of the outer tube, Any shape may be used as long as the suspension can be prevented from flowing into a portion to be sealed with the inner pipe downstream (lower side).
[0050]
As such an example, in the reservoir in the embodiment, the end on the sealing portion side is substantially perpendicular to the tube axis A, but the end on the sealing portion side approaches the tube axis. Therefore, the flat portion in the embodiment may be formed in a concave shape (a groove shape over the entire circumference) so as to enter the inside. In order to form such a concave shape, an outer tube valve is formed in the same manner as in the prior art, and then the flat portion of the reservoir is heated and softened, and a forming jig or the like corresponding to the concave shape is pressed from the outside. What is necessary is just to shape.
[0051]
Even if the reservoir is concave as described above, even if the outer tube is turned upside down after the suspension for the protective layer is applied and discharged into the outer tube, the suspension remaining inside the outer tube remains in the outer tube. Even if it hangs down along the inner surface, it accumulates in the accumulating portion, so that it does not flow into the sealing portion (extended portion) with the inner tube.
When the reservoir portion is formed in a concave shape, the shape may be a “V” shape or a “S” shape.
[0052]
3. About sealing part
In the above embodiment, the end of the inner tube is formed so as to spread outward, and the tip is sealed to the extension of the outer tube. The shape may be changed and sealing may be performed. As an example of such a shape change, the reservoir of the outer tube is further extended inward, and the end of the inner tube on the opening side is formed into a straight tube without expanding outward. May be sealed. That is, a reservoir may be formed at the periphery of the opening of the outer tube to seal the periphery of the opening to the inner tube.
[0053]
In the present invention, the position of the reservoir is determined by the sealing position between the inner tube and the outer tube, the shape of the outer tube near the sealing position, and the like. That is, in the embodiment, the reservoir portion is separated from the sealing portion, while the reservoir portion may start from the sealing portion as in the modification in this section. Therefore, the term "in the vicinity of the sealing portion" in the present invention includes a case where the sealing portion is slightly apart from the sealing portion and a case where the sealing portion becomes an end of the storage portion, as described above.
[0054]
4. Suspension application
In the above embodiment, the opening of the outer tube is directed upward or downward when the protective layer is formed, that is, when the suspension is applied and then dried. At this time, the tube axis of the outer tube matches the direction in which gravity acts (hereinafter, referred to as “vertical axis”), but the tube axis of the outer tube may be inclined with respect to the vertical axis.
[0055]
That is, when the suspension is ejected from the application nozzle toward the inner surface of the outer tube (FIG. 2 (a)), the suspension that accumulates in the outer tube after the ejection is applied to the application site on the inner surface of the outer tube. The outer tube can be inclined to such an extent that it does not exceed it. On the other hand, when the outer tube is turned over and its opening is turned downward after discharging the suspension in the outer tube, the suspension hanging down along the inner wall of the outer tube accumulates on a portion of the reservoir portion. Can be tilted to a degree.
[0056]
Therefore, in the present invention, the state in which the “opening of the outer tube is upward” or “downward” does not mean only the state in which the tube axis of the outer tube coincides with the vertical axis, as described above. This also includes a state in which the tube axis of the outer tube is inclined with respect to the vertical axis.
[0057]
【The invention's effect】
As described above, the light-emitting bulb according to the present invention is sealed in the outer tube having the opening and the protective layer formed on the inner surface at the periphery of the opening in a state where the inner tube is inserted. A light-emitting bulb for an electrodeless lamp, wherein the outer tube has a dripping protective liquid reservoir near the sealing portion and on the protective layer side, for example, on the inner surface of the outer tube. When the protective liquid is applied and dried, the protective liquid hanging down along the inner surface of the outer pipe can be stored in the reservoir even if the opening of the outer pipe is turned downward, and the protective liquid is sealed with the inner pipe. It can be prevented from flowing into the planned site. Therefore, the step of removing the protective layer, which is required in the conventional manufacturing method, can be omitted, and the productivity can be improved.
[0058]
According to the method for manufacturing a light-emitting bulb according to the present invention, the outer tube having an opening and a protective layer formed on the inner surface is sealed to the peripheral portion of the opening in a state where the inner tube is inserted. A method of manufacturing a light-emitting bulb for an electrodeless lamp, comprising: forming a reservoir in the outer tube in the vicinity of the sealing portion and on the side where the protective layer is to be formed; The formation of the protective layer on the inner surface of the tube includes a step of applying a suspension for the protective layer to the inner surface, and the step of suspending the outer tube inner surface with the opening of the outer tube facing downward. And the step of drying the applied suspension while being stored in the storage portion, for example, when drying after applying the suspension to the inner surface of the outer tube, the opening of the outer tube is directed downward The suspension hanging down along the inner surface of the outer tube can be stored in the reservoir, and the suspension It can be prevented from flowing into wearing the proposed site.
[Brief description of the drawings]
FIG. 1 is a front view illustrating an entire configuration of an electrodeless fluorescent lamp according to an embodiment of the present invention, in which a part of the electrodeless fluorescent lamp is cut away.
FIG. 2 is a diagram illustrating a step of forming a protective layer on the inner surface of the outer tube according to the embodiment of the present invention.
FIG. 3 is a diagram illustrating a conventional process of forming a protective layer on the inner surface of an outer tube.
[Explanation of symbols]
10 lamps
12 Light-emitting bulb
13 Sealing part
15 outer tube
16 Inner tube
17 Container part
18 Extension
19 Reservoir
19a Flat part

Claims (13)

A light-emitting bulb for an electrodeless lamp, which is sealed in a peripheral portion of the opening in a state where the inner tube is inserted and fitted in an outer tube having an opening and a protective layer formed on the inner surface,
The light-emitting bulb for an electrodeless lamp, wherein the outer tube has a dripping protection liquid reservoir near the sealing portion and on the side of the protection layer. The light-emitting bulb for an electrodeless lamp according to claim 1, wherein the outer tube has a substantially axially symmetric shape and one end in the axial direction is open. The light-emitting bulb for an electrodeless lamp according to claim 1, wherein a part of the drooping protection liquid reservoir extends outward from the vicinity of the sealing portion. The light-emitting bulb for an electrodeless lamp according to claim 2, wherein the drooping protection liquid reservoir has a substantially flat portion formed in a direction substantially orthogonal to the axis. The light emitting bulb for an electrodeless lamp according to any one of claims 1 to 4, wherein a fluorescent layer is formed on an inner layer of the protective layer. 6. The fluorescent layer according to claim 5, wherein a fluorescent layer is also formed on an inner surface of the drooping protection liquid reservoir, and a thickness of the fluorescent layer is larger than a fluorescent layer formed in another portion. Light emitting bulb for electrode lamp. An electrodeless lamp comprising the light-emitting bulb according to claim 1. The electrodeless lamp includes a holding member that holds the light emitting bulb, and a cover that covers an outer surface of the dripping protective liquid reservoir of the arc tube held by the holding member so as to be invisible. The electrodeless lamp according to claim 7, characterized in that: A method for manufacturing a light-emitting bulb for an electrodeless lamp, wherein the light-emitting bulb is sealed in a peripheral portion of the opening in a state where the inner tube is inserted into an outer tube having an opening and a protective layer formed on an inner surface. ,
In the outer tube, a reservoir is formed in the vicinity of the sealing portion and on the side where the protective layer is to be formed,
Formation of the protective layer on the inner surface of the outer tube,
Applying a suspension for the protective layer to the inner surface,
Drying the applied suspension while the suspension suspending in the reservoir with the opening of the outer tube facing downward and hanging down the inner surface of the outer tube. A method for manufacturing a light-emitting bulb for a lamp. Between the coating step and the drying step,
The method for manufacturing a light-emitting bulb for an electrodeless lamp according to claim 9, wherein a step of sucking and discharging the suspension after application is performed with the opening facing upward. The method according to claim 9 or 10, wherein the drying step is performed while rotating the outer tube around the tube axis. The method of manufacturing a light-emitting bulb for an electrodeless lamp according to any one of claims 9 to 11, wherein the upside-down of the outer tube is performed while rotating the outer tube around the tube axis. . The method according to any one of claims 10 to 12, wherein the application and discharge of the suspension are performed by a nozzle having a function of ejecting the suspension and a function of suctioning and discharging the suspension. A method for producing a light-emitting bulb for an electrodeless lamp as described above.

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