JP2008251425A - Fluorescent-film forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluorescent-film forming device capable of suppressing a heat loss at a small value and performing a temperature control easily. <P>SOLUTION: The fluorescent-film forming device 1 forms a fluorescent film by heating a lamp tube 2 with a fluorescent material coated on its inner periphery. An air containing oxygen is introduced from the outside towards one end in the longitudinal direction of the internal lamp tube 2. The forming device 1 has a lamp-tube heating part 3 constituted to externally exhaust the air from the another end in the longitudinal direction of the lamp tube 2 after it is thermally treated. Further, the device has a circulatory pathway 15 to repeatedly introduce a volume of the air exhausted to the outside of the lamp-tube heating part 3 towards one end in the longitudinal direction of the lamp tube 2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fluorescent film forming apparatus that forms a fluorescent film by heat-treating a lamp tube having an inner peripheral surface coated with a phosphor.

  Conventionally, in order to manufacture a lamp tube such as a cold cathode tube used as a light source for a backlight of a liquid crystal display, for example, a fluorescent film is formed by heat-treating a lamp tube coated with a phosphor on its inner peripheral surface. A fluorescent film forming apparatus 1 as shown is known (for example, Patent Document 1).

  The fluorescent film forming apparatus 1 includes a lamp tube heating unit 3 that heats the lamp tube 2, a lamp tube supply unit 4 that supplies the lamp tube 2 to the lamp tube heating unit 3, and heating by the lamp tube heating unit 3. And a lamp tube collecting unit 5 for collecting the processed lamp tube 2. Further, the fluorescent film forming apparatus 1 is provided with transport means 6 for transporting the lamp tube 2 from the lamp tube supply unit 4 through the lamp tube heating unit 3 to the lamp tube recovery unit 5.

  The conveying means 6 conveys the lamp tube 2 along its width direction. The transport means 6 is an endless transport device that circulates the lamp tube supply section 4, the lamp tube heating section 3, and the lamp tube collection section 5, and specifically includes a chain 7 (see FIG. 3) and A plurality of lamp tube holding members 8 provided on the chain 7 are provided.

  In addition, as shown in FIG. 3, the conveyance means 6 in the fluorescent film forming apparatus 1 passes through the lamp tube heating part 3 in the upper half of the circuit and passes through the base part 9 in the lower half. The base unit 9 accommodates a transport driving unit that transports and drives the transport unit 6.

  The lamp tube holding member 8 is a cylindrical body that accommodates the lamp tube 2 along the longitudinal direction, and is formed by opening both ends. The lamp tube holding member 8 is configured to be rotatable about the central axis of the tube, and the lamp tube 2 accommodated in the lamp tube holding member 8 is rotated by the rotation of the lamp tube holding member 8. To do. Thereby, the heat treatment of the lamp tube 2 is performed uniformly.

  Further, the lamp tube holding member 8 is formed to have a larger diameter than the diameter of the lamp tube 2 and has a size capable of accommodating at least two lamp tubes 2 and 2 in the case shown in FIG. Note that quartz is used as the material of the lamp tube holding member 8.

  The lamp tube supply unit 4 supplies the lamp tube 2 with its width direction coincident with the transport direction of the transport means 6, and the lamp tube aligning unit 10 for adjusting the direction of the lamp tube 2. Is provided adjacent to the lamp tube supply unit 4. Further, the lamp tube 2 collected from the lamp tube collection unit 5 is received by a lamp tube storage unit 11 provided adjacent to the lamp tube collection unit 5.

  The lamp tube heating unit 3 is provided with a heater 12 (see FIG. 3), and the phosphor applied to the inner peripheral surface of the lamp tube 2 is baked by the heat of the heater 12, Oxygen is needed. For this reason, the fluorescent film forming apparatus 1 is further provided with an oxygen supply unit 13 for supplying oxygen.

  The oxygen supply unit 13 supplies oxygen into the lamp tube 2 through an opening at one end in the longitudinal direction, and is opposed to one end in the longitudinal direction of the lamp tube 2 passing through the lamp tube heating unit 3. Are arranged as follows. Specifically, the oxygen supply unit 13 includes a plurality of nozzle bodies 14 that discharge oxygen, and the nozzle bodies 14 are arranged along the longitudinal direction of the lamp tube 2 (that is, the direction orthogonal to the transport direction). The oxygen is intermittently supplied to and from the inside of the tube heating unit 3. More specifically, the nozzle body 14 is inserted into the lamp tube holding member 8 that holds the lamp tube 2 and supplies oxygen.

By the way, the lamp tube heating unit 3 needs to heat the lamp tube 2 at a predetermined high temperature (for example, about 700 ° C.). On the other hand, the lamp tube heating unit 3 is open on the upstream side and the downstream side in the transport direction so as to always receive the lamp tube 2 supplied from the lamp tube supply unit 4. In addition, the lamp tube heating unit 3 is closed on both sides along the transport direction by walls, and the wall is formed with a plurality of holes that can receive the nozzle body 14 of the oxygen supply unit 13. Yes.
JP 2001-351517 A

  For this reason, the heat inside the lamp tube heating section 3 is always released from these open portions, and the conventional phosphor film forming apparatus 1 has a problem that heat loss is very large. For this reason, the heater 12 of the lamp tube heating unit 3 is set to a temperature (for example, about 1000 ° C.) sufficiently higher than the actual temperature at which the lamp tube 2 is heated in consideration of the loss of heat released to the outside. I have to.

  In addition, when the temperature of the lamp tube 2 is increased, the emission color deviates from the original color. On the other hand, when the temperature for the heat treatment is lowered, the impurities remain without being burned and abnormal discharge occurs, or the phosphors are peeled off without being well fixed on the inner peripheral surface of the lamp tube 2. is there. Such a situation is particularly likely to occur in the recent lamp tube 2 having a long overall length. Thus, the conventional fluorescent film forming apparatus 1 has a problem that it is difficult to control the temperature in the lamp tube heating unit 3.

  Therefore, an object of the present invention is to provide a fluorescent film forming apparatus that can suppress heat loss to a small level and can easily perform temperature control.

  A fluorescent film forming apparatus according to the present invention is a fluorescent film forming apparatus that forms a fluorescent film by heat-treating a lamp tube having an inner peripheral surface coated with a phosphor, and includes one end in the longitudinal direction of the lamp tube existing inside. A lamp tube heating section configured such that a gas containing oxygen is introduced from the outside toward the side, and the gas after heat-treating the lamp tube is discharged from the other longitudinal end of the lamp tube to the outside. And a circulation path for introducing a part of the gas discharged to the outside of the lamp tube heating unit into the lamp tube heating unit again toward one end in the longitudinal direction of the lamp tube.

  According to the fluorescent film forming apparatus having the above-described configuration, since there is a circulation path for introducing a part of the gas discharged to the outside of the lamp tube heating unit into the lamp tube heating unit again, the inside of the lamp tube heating unit The heat of can be reused effectively. In addition, by introducing a part of the high-temperature gas discharged from the lamp tube heating unit into the lamp tube heating unit again, a change over time in the temperature inside the lamp tube heating unit can be reduced.

  Further, since a part of the gas discharged to the outside of the lamp tube heating unit is introduced into the lamp tube heating unit toward one end side in the longitudinal direction of the lamp tube, the flow of gas circulating through the circulation path (Airflow) is not disturbed, and oxygen can be put into the airflow smoothly into the lamp tube.

  The phosphor film forming apparatus preferably includes an oxygen supply unit that supplies oxygen, and oxygen supplied from the oxygen supply unit is drawn into the circulation path by a gas flow circulating in the circulation path. .

  In this way, oxygen is automatically drawn in by the air flow, so that oxygen can be fed efficiently and the configuration of the oxygen supply unit can be simplified compared to the conventional one. The loss of heat due to the provision of the supply unit can be suppressed to be smaller than in the past.

  Moreover, in the said fluorescent film formation apparatus, the structure by which the heater which heats the said lamp tube is provided in the said lamp tube heating part is preferable.

  In this way, the heat generated by the heater can be efficiently used for the heat treatment of the lamp tube.

  As described above, according to the phosphor film forming apparatus of the present invention, heat loss can be suppressed to a low level, and temperature control can be easily performed.

  Hereinafter, an embodiment of a fluorescent film forming apparatus according to the present invention will be described with reference to the drawings.

  A fluorescent film forming apparatus 1 according to this embodiment forms a fluorescent film by heat-treating a lamp tube 2 having an inner peripheral surface coated with a phosphor, and a basic configuration is a conventional fluorescent film forming apparatus. 1 is characterized in that the lamp tube heating section 3 for heat-treating the lamp tube 2 and the surrounding configuration are used. Therefore, hereinafter, the basic configuration will be described with reference to FIGS. 2 and 3 used in the description of the conventional phosphor film forming apparatus 1, and the characteristic configuration will be described with reference to FIG.

  First, as shown in FIGS. 2 and 3, the fluorescent film forming apparatus 1 has a configuration common to the conventional one, as shown in FIGS. 2 and 3, and a lamp tube that supplies the lamp tube 2 to the lamp tube heating unit 3. A supply unit 4 and a lamp tube recovery unit 5 for recovering the lamp tube 2 heated by the lamp tube heating unit 3 are provided. Further, the fluorescent film forming apparatus 1 is provided with transport means 6 for transporting the lamp tube 2 from the lamp tube supply unit 4 through the lamp tube heating unit 3 to the lamp tube recovery unit 5. Here, the lamp tube 2 is heat-treated in a state where both ends in the longitudinal direction are opened in order to fire the phosphor applied on the inner peripheral surface.

  The conveying means 6 conveys the lamp tube 2 along its width direction. The transport means 6 is an endless transport device that circulates the lamp tube supply unit 4, the lamp tube heating unit 3, and the lamp tube collection unit 5, and specifically includes a chain 7 and a plurality of chains 7. And a lamp tube holding member 8 provided.

  The lamp tube holding member 8 is a cylindrical body that accommodates the lamp tube 2 along the longitudinal direction, and is formed by opening both ends. The lamp tube holding member 8 is configured to be rotatable about the central axis of the tube, and the lamp tube 2 accommodated in the lamp tube holding member 8 is rotated by the rotation of the lamp tube holding member 8. To do. Thereby, the heat treatment of the lamp tube 2 is performed uniformly.

  Further, the lamp tube holding member 8 is formed to have a larger diameter than the diameter of the lamp tube 2 and has a size capable of accommodating at least two lamp tubes 2 and 2 in the case shown in FIG. Note that quartz is used as the material of the lamp tube holding member 8.

  The lamp tube supply unit 4 supplies the lamp tube 2 with its width direction coincident with the transport direction of the transport means 6, and the lamp tube aligning unit 10 for adjusting the direction of the lamp tube 2. Is provided adjacent to the lamp tube supply unit 4. Further, the lamp tube 2 collected from the lamp tube collection unit 5 is received by a lamp tube storage unit 11 provided adjacent to the lamp tube collection unit 5.

  Next, the characteristic part of the fluorescent film forming apparatus 1 according to the present embodiment will be described. The lamp tube heating unit 3 is configured such that a gas containing oxygen is introduced from the outside toward one end in the longitudinal direction of the lamp tube 2 existing inside, and the gas after the heat treatment of the lamp tube 2 is performed on the lamp tube 2. It is configured to be discharged to the outside from the other end in the longitudinal direction. Further, the fluorescent film forming apparatus 1 introduces a part of the gas discharged to the outside of the lamp tube heating unit 3 into the lamp tube heating unit 3 again toward the one end side in the longitudinal direction of the lamp tube 2. A circulation path 15 is provided.

  The phosphor film forming apparatus 1 includes an oxygen supply unit 16 that supplies oxygen, and oxygen supplied from the oxygen supply unit 16 is drawn into the circulation path 15 by a gas flow that circulates in the circulation path 15. It is. The oxygen supply unit 16 may supply only oxygen, or may actually supply air to supply oxygen contained in the air.

  Further, in the fluorescent film forming apparatus 1, a heater 12 for heating the lamp tube 2 is provided in the lamp tube heating unit 3.

  Specifically, the lamp tube heating unit 3 is provided in a lamp tube heater 17 provided in the phosphor film forming apparatus 1. The lamp tube heater 17 will be described below.

  The lamp tube heater 17 includes the lamp tube heating unit 3 and a return unit 20 formed from an exhaust port 18 of the lamp tube heating unit 3 to an intake port 19 of the lamp tube heating unit 3. The The circulation path 15 is a path that goes around the lamp tube heating unit 3 and the return unit 20.

  The return unit 20 bends upward from the vicinity of the exhaust port 18 of the lamp tube heating unit 3, passes above the lamp tube heating unit 3, and extends toward the intake port 19 of the lamp tube heating unit 3, It is provided as a space that rises upward from a predetermined position and inclines obliquely downward toward the vicinity of the inlet 19 of the lamp tube heating unit 3.

  The intake port 19 is arranged to face the opening of the lamp tube holding member 8 that passes through the lamp tube heating unit 3. For this reason, the gas introduced into the inside from the intake port 19 is smoothly supplied to the lamp tube 2 held by the lamp tube holding member 8. Similarly, the exhaust port 18 is disposed so as to face the opening of the lamp tube holding member 8 that passes through the lamp tube heating unit 3. For this reason, the gas after heat-treating the lamp tube 2 is smoothly discharged from the exhaust port 18.

The oxygen supply unit 16 is provided in the lamp tube heater 17, and the oxygen supply unit 16 is configured to supply oxygen to the return unit 20. Preferably, the oxygen supply unit 16 is arranged so that the supply port 21 faces the intake port 19 of the lamp tube heating unit 3.
A blower 22 is disposed at a predetermined location of the return unit 20. The air blower 22 is disposed at a connecting portion between a portion rising above the return portion 20 and a portion inclined obliquely downward. Specifically, the air blower 22 includes a fan 23 and a fan rotation driving unit 24 that rotationally drives the fan 23. More specifically, the fan 23 includes a plurality of blades arranged annularly around and around the rotation axis, and the gas flowing into the space defined by the plurality of blades is radially A so-called sirocco fan that is sent outward is used.

  Furthermore, the lamp tube heater 17 includes a discharge unit 25 that discharges a part of the gas flowing through the return unit 20 to the outside. Further, the lamp tube heater 17 is provided with an intake part 26 for taking outside air into the return part, and the exhaust part 25 and the intake part 26 constitute a ventilation means 27 for ventilating the return part 20. Prepare. The intake portion 26 is disposed on the upstream side of the circulation path 15 with respect to the discharge portion 25.

  By the way, the lamp tube heating unit 3 is provided over a predetermined length along the conveying direction of the conveying means 6, and the lamp tube 2 conveys the inside of the lamp tube heating unit 3 from the upstream side to the downstream side. It is heat-treated while being done. Accordingly, the lamp tube heating unit 3 is provided with six intake ports 19 and six exhaust ports 18 along the transport direction. The lamp tube heater 17 is provided with two air blowers 22 along the transport direction.

  The return unit 20 extends along the transport direction in correspondence with all the exhaust ports 18 in the vicinity of the exhaust port 18 of the lamp tube heating unit 3. In the vicinity of the intake port 19, it extends along the transport direction corresponding to all the intake ports 19. In addition, since the number of the air blowers 22 is less than the number of the exhaust ports 18 and the air intake ports 19, the return unit 20 converges from the vicinity of the exhaust ports 18 to the portion where the air blowers 22 are provided, It is provided in a shape that diverges from a portion where the blower 22 is provided to a portion near the air inlet 19.

  In addition, the conveyance means 6 in the fluorescent film forming apparatus 1 passes through the lamp tube heating unit 3 in the upper half of one round as shown in FIG. 1 (also shown in FIG. 3 for reference), It passes through the base part 9 in the lower half. The base unit 9 accommodates a transport driving unit 28 that transports and drives the transport unit 6.

  As described above, according to the phosphor film forming apparatus according to the present embodiment, heat loss can be suppressed to a low level, and temperature control can be easily performed.

  That is, according to the fluorescent film forming apparatus 1 having the above-described configuration, since it includes the circulation path 15 for introducing a part of the gas discharged to the outside of the lamp tube heating unit 3 into the lamp tube heating unit 3 again, The heat inside the lamp tube heating unit 3 can be effectively reused. In addition, by introducing a part of the high-temperature gas discharged from the lamp tube heating unit 3 into the lamp tube heating unit 3 again, a change with time in the temperature inside the lamp tube heating unit 3 can be reduced. .

  Further, a part of the gas discharged to the outside of the lamp tube heating unit 3 is introduced into the lamp tube heating unit 3 toward one end in the longitudinal direction of the lamp tube 2, and thus circulates in the circulation path 15. The gas flow (air flow) is not disturbed, and oxygen can be put on the air flow and smoothly fed into the lamp tube 2.

  Further, the phosphor film forming apparatus 1 includes an oxygen supply unit 16 that supplies oxygen, and oxygen supplied from the oxygen supply unit 16 is supplied to the circulation path 15 by a gas flow that circulates in the circulation path 15. Be drawn. That is, since oxygen is automatically drawn by the air flow, oxygen can be efficiently fed, and the configuration of the oxygen supply unit 16 can be simplified as compared with the conventional one. The heat loss due to the provision of 16 can be suppressed to be smaller than in the prior art.

  In the fluorescent film forming apparatus 1, a heater 12 for heating the lamp tube 2 is provided in the lamp tube heating unit 3. Therefore, the heat generated by the heater 12 can be efficiently used for the heat treatment of the lamp tube 2.

  The fluorescent film forming apparatus according to the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

  For example, in the above-described embodiment, the transport unit 6 has been described as an endless transport device including the chain 7 and a plurality of lamp tube holding members 8 provided on the chain 7, but the present invention is not limited thereto. It may be configured by a plurality of transport rollers arranged in the transport direction, and the mounted lamp tube may be transported from the upstream side to the downstream side by rotating the transport roller.

  In the above embodiment, the intake unit 26 for taking in outside air and the oxygen supply unit 16 for supplying oxygen are provided separately in the return unit 20, but the present invention is not limited to this. Only one of the inlet part and the oxygen supply part may be provided, and the outside air may be taken from only one of them.

  In addition, the present invention describes a fluorescent film forming apparatus, but a glass bulb not coated with a fluorescent solution is similarly passed through the lamp tube heating unit 3 while rotating the lamp tube 2 with the lamp tube holding member 8. Therefore, it is possible to correct the bending at the time of purchasing the lamp tube, and even in this case, there is an effect that heat loss can be suppressed small.

  The phosphor film forming apparatus according to the present invention can suppress heat loss to a small level and can easily perform temperature control. Therefore, it is particularly useful for manufacturing a lamp tube such as a cold cathode tube used as a light source of a backlight of a liquid crystal display.

Sectional side view which shows the fluorescent film forming apparatus which concerns on embodiment of this invention Plan view showing a conventional phosphor film forming apparatus Sectional front view showing a conventional phosphor film forming apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fluorescent film forming apparatus 2 Lamp tube 3 Lamp tube heating part 4 Lamp tube supply part 5 Lamp tube collection | recovery part 6 Conveying means 7 Chain 8 Lamp tube holding member 9 Base part 10 Lamp tube alignment part 11 Lamp tube storage part 12 Heater 15 Circulation Route 16 Oxygen supply unit 17 Lamp tube heater 18 Exhaust port 19 Intake port 20 Return unit 21 Supply port 22 Blower 23 Fan 24 Fan rotation drive unit 25 Discharge unit 26 Intake unit 27 Ventilation means 28 Transport drive unit

Claims (3)

A fluorescent film forming apparatus that forms a fluorescent film by heat-treating a lamp tube having an inner peripheral surface coated with a phosphor,
A gas containing oxygen is introduced from the outside toward one end in the longitudinal direction of the lamp tube existing inside, and the gas after heat-treating the lamp tube is discharged to the outside from the other end in the longitudinal direction of the lamp tube. A lamp tube heating section configured as follows,
A fluorescent film forming apparatus comprising a circulation path for introducing a part of the gas discharged to the outside of the lamp tube heating unit into the lamp tube heating unit again toward one end in the longitudinal direction of the lamp tube . An oxygen supply unit for supplying oxygen;
The phosphor film forming apparatus according to claim 1, wherein oxygen supplied from the oxygen supply unit is drawn into the circulation path by a gas flow circulating in the circulation path.   The fluorescent film forming apparatus according to claim 1, wherein a heater for heating the lamp tube is provided in the lamp tube heating unit.

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