JP2933610B1 - Plasma display panel manufacturing equipment - Google Patents

Abstract

A PDP for sealing front and back substrates at a peripheral portion of a PDP assembly and exhausting and discharging a discharge gas inside the assembly.
The operation of attaching the working head to the tip tube in the manufacturing apparatus is omitted. A vacuum heating furnace for accommodating a PDP assembly.
In addition, a lamp house 25 is provided so as to be able to ascend and descend in an airtight manner by a bellows 3, a work head 15 is supported on the lamp house 25, and the work head 15 has a heat-resistant glass window 1 whose upper surface is airtight.
9, a relay chamber 16 having an opening 18 on the lower surface, a cooling water jacket 21 and an annular packing 17 surrounding the opening 18 are provided.
6 is connected to a vacuum evacuation system and a discharge gas supply source, and a heat-resistant glass window 27 for sealing the lower surface of the lamp house 25 airtightly, a heat ray radiation source 28
Is provided with a reflecting mirror 29 which is concentrated at the tip of the mirror.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for manufacturing a plasma display panel (hereinafter abbreviated as "PDP"), and more specifically, to sealing of a peripheral portion of a PDP assembly, evacuation of the inside, introduction of gas, and sealing. The present invention relates to an apparatus for continuously performing steps.

[0002]

2. Description of the Related Art In a PDP, a front substrate and a rear substrate are sealed at their peripheral edges, and the inside of the PDP is evacuated via a chip tube provided at an appropriate position on the rear substrate. After the discharge gas is introduced into the chip tube, the chip tube is melted and sealed. Conventionally, for example, FIG.
And an apparatus as shown in FIG.

In FIG. 5, reference numeral 60 denotes a PDP assembly,
The front substrate 61 and the rear substrate 62 are overlapped with a frit adhesive 63 sandwiched between both peripheral portions, and the state is held by a clip 64. Small holes 6 in place on rear substrate 62
5 is drilled and a tip tube 6 having a flange 66 therein
7 are placed with frit adhesive 68 in between, and clips 69
Is held by

Prior to the work, a work head 70 is manually attached to the tip tube 67. The working head 70 includes a short cylindrical main body 71, an annular packing 73 and a piston-like member 74 housed in a lumen 72 thereof, and a screw cap 75 attached to an upper portion of the main body 71. Inside the main body 71, there is a cooling water jacket 76 surrounding the lumen 72, from which a water supply pipe 77 and a drain pipe 78 extend to the outside world, and a chip pipe 67 can pass through the center of the bottom of the lumen 72. A small hole 79 is drilled, and a screw cap 75 is provided on the outer peripheral surface of the main body 71.
Is provided. A supply / exhaust pipe 81 that opens at the center of the lower surface of the piston 74 extends from the center of the upper surface of the piston-like member 74. The screw cap 75 has a hole 82 at the center of the upper surface through which the supply / exhaust pipe 81 passes.
Of the piston-like member 74
Is pressed down, thereby pressing the annular packing 73 to make it tightly adhere to the tip tube 67.

When the working head 70 is attached to the tip tube 67 as shown in FIG.
.. Are accommodated in a heating furnace 83,
Each of the supply / exhaust pipes 81 is connected to a total supply / exhaust pipe 85 via a flexible pipe and an on / off valve 84, 84,. And a discharge gas supply source via an on-off valve 88. Although not shown, the water supply pipe 77 and the drainage pipe 78 of each working head 70 are also connected to appropriate cooling water pipes outside the furnace via flexible pipes.

An electric heater 89 and a blower 90 are provided in the heating furnace 83 to circulate hot air to heat the PDP assemblies 60, 60.
Are melted to seal between the front substrate 61 and the rear substrate 62, and the chip tube 67 is fused to the rear substrate 62. During this time, the annular packing 73 is cooled by the cooling water in the water jacket 76 and is protected from heat. Next, the temperature inside the furnace was appropriately lowered, and the evacuation system was operated to operate the PDP.
After sufficiently exhausting the interior of the assemblies 60, 60,..., Discharge gas is introduced, the heating furnace 83 is opened, and the tip tubes 67, 67,. Stop.

[0007]

In the above-mentioned operation, the tip tube 67 has a diameter of, for example, 5 to 7 mm and a length of 80 to 10 mm.
Since it is as long as 0 mm, it cannot stand alone at a predetermined position unless the clip 69 is used, and the mounting of the working head 70 to this requires a skilled manual operation so that the tip tube 67 does not move or fall down. Since it is necessary, automation is difficult, and since the tip tube remaining in the sealed PDP assembly is too long, it has been necessary to re-short it again manually by hand.

Further, since the working head 70 is connected to a flexible tube for supplying and discharging the cooling water and for exhausting the inside of the PDP assembly and for introducing a discharge gas, the tip tube 67 falls down due to stress received from the tube. The temperature distribution of the PDP assembly 60 is likely to be non-uniform because the working head 70, which is water-cooled, cuts off the radiant heat from the heater.
To the rear substrate 62. The present invention seeks to solve these problems at once.

[0009]

In the present invention, a vacuum heating furnace having a heating heater inside and connected to a vacuum exhaust system is used. A lamp house is provided in the heating furnace so as to be able to move up and down, and a working head is supported at a lower end of the lamp house. The PDP assembly in which the tip tube is set on the back substrate is placed in a vacuum heating furnace with the tip tube being right under the working head.

[0010] A relay chamber is provided inside the work head. The upper part of the relay chamber is closed by a heat-resistant glass window provided on the upper surface of the work head in an airtight manner, and the lower part is opened to the lower surface of the work head. An annular packing is supported on the lower surface of the working head surrounding this opening, and a cooling jacket is present inside the working head to protect the packing from heat. The inside of the relay room is connected to a vacuum exhaust system and a discharge gas supply source. In the lamp house, there are a radiation source of heat rays and a reflector for concentrating the heat rays in the relay room through the heat-resistant glass window.

In the above-mentioned apparatus, the working head is placed in the ascending position together with the lamp house, the PDP assembly in which the chip tubes are erected on the back substrate is put into a vacuum heating furnace, and the heating heater is operated under atmospheric pressure. Then, the PDP assembly is heated to seal the peripheral portion and join the chip tube to the back substrate. After this, the furnace temperature is lowered to a predetermined temperature, and when the temperature is stabilized, the occluded gas inside the PDP assembly is sufficiently discharged.

When the temperature in the furnace is further reduced and the temperature of the PDP assembly has dropped to such an extent that the annular packing is not damaged, the working head is lowered together with the lamp house. Then, the chip tube enters the relay chamber, the annular packing surrounds the chip tube, and comes into close contact with the rear substrate surface, and the relay chamber becomes airtight. Therefore, if the inside of the relay chamber is evacuated and outside air is introduced into the vacuum heating furnace, the working head is strongly pressed against the rear substrate due to the pressure difference, and the airtightness of the relay chamber is further improved. In addition, by returning the inside of the vacuum heating furnace to the atmospheric pressure in this way, when the discharge gas is introduced into the PDP assembly in the next step, it is possible to prevent the PDP assembly from being expanded and damaged by the internal pressure. it can.

When the temperature of the PDP assembly drops to near room temperature, the evacuation of the relay room is stopped and a discharge gas is introduced.
When the heat ray radiation source in the lamp house is turned on, the heat rays are concentrated by the reflector at the tip of the tip tube in the relay room, and this is instantaneously heated to several hundred degrees Celsius and melted and sealed.

As described above, since the exhaust inside the PDP assembly, the discharge gas introduction and the sealing can be performed without bringing the working head into contact with the chip tube at all, the chip tube can be made small in diameter and extremely short. As a result, the exhaust resistance inside the PDP assembly can be reduced, and a step of re-cutting the sealed chip tube shortly is not required. Then, since the unnecessary portion of the chip tube does not remain in the working head after the sealing of the chip tube, a step of eliminating the unnecessary portion can be omitted.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS It is desirable to provide a water jacket in the inside of the working head to circulate cooling water, whereby the temperature of the packing between the back substrate and the packing which keeps the heat-resistant glass window tight is kept. The rise can be suppressed.
As a result, the work head can be coupled to the tip tube while the temperature of the PDP assembly is fairly high, so that the inside can be cleaned with an inert gas or more completely evacuated.

It is desirable to close the front of the lamp house with an airtight heat-resistant glass window, so that the lamp house can be placed outside the vacuum space of the heating furnace.
Vacuum discharge of the power circuit of the heat radiation source can be prevented.
Also, in order to place the lamp house outside the vacuum space, a bellows is provided around the lamp house, the upper end of which is hermetically connected to the furnace wall of the heating furnace, and the lower end of which is connected to the lower end of the lamp house. Advantageously, it is hermetically bonded around the heat-resistant glass window.

Further, when the PDP assembly is heated to a high temperature in a heating furnace for sealing the peripheral portion of the PDP assembly or joining the chip tube to the rear substrate, the work head and the chip tube at the elevated position are required. Move the movable heater into the space between the
It is desirable to help increase the temperature near the tip tube. The movable heater can be retracted to a position where it does not hinder the work head when it is lowered. Also,
It is preferable that a cooling water jacket is provided on the upper surface of the movable heater, that is, on the side opposite to the tip tube, so that the working head is not heated when the movable heater is in the forward position.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, 1 is a PDP assembly, 2 is its front substrate, and 3 is its back substrate. As shown in FIG. 4, a small hole 56 is formed in the rear substrate 3 at an appropriate position, and a counterbore 57 is formed around the small hole 56 on the rear surface (the upper surface in the figure).
The tip tube 4 made of low-melting glass is planted here. The dimensions of the tip tube 4 are, for example, an outer diameter of 2 to 3 m.
m, 15 to 25 mm in length. Reference numeral 58 denotes a frit adhesive ring placed on the back substrate 3 surrounding the chip tube 4.

The PDP assembly 1 is housed in a vacuum heating furnace 5 as shown in FIG. The heating furnace 5 has electric heaters 6, 7, 8, and 9 arranged along its inner wall, and has a movable electric heater 10 described later. The inside of the heating furnace 5 is evacuated by an evacuation system 12 via an on-off valve 11 and communicates with the outside world via a leak valve 13. As shown in FIG. 1, a work head 15 is arranged so as to face the chip tube 4 erected on the PDP assembly 1.

As shown in FIG. 1, the working head 15 has a relay chamber 16 inside, and an opening 18 surrounded by a packing 17 exists below the relay chamber 16.
A heat-resistant glass window 19 is hermetically provided on the upper surface of 6. The inside of the relay chamber 16 is connected from a supply / exhaust pipe 20 to a supply / exhaust pipe line 42 shown in FIG. 2 via a flexible pipe (not shown). Tube 2
2 and a flexible tube (not shown) from the outflow tube 23 (not shown)
Are connected to a cooling water supply pipe 43 and a drain pipe 44 shown in FIG. The working head 15 is fixed to the lamp house 2 by rods 24, 24 penetrating it loosely.
5 and is lightly pushed down by springs 26, 26 loosely wound around rods 24, 24.

A heat-resistant glass window 27 is provided on the lower end surface of the lamp house 24 so as to face the work head 15.
A heat source 2 such as a halogen lamp is provided in the lamp house 25.
8 and a reflecting mirror 29 are provided. The reflecting mirror 29 forms a spheroid having a focal point in the heat ray source 28 and the inside of the relay chamber 16.

From the lower part of the lamp house 25, a bellows 30 surrounding the lamp house 25 extends upward. A support tube 31 extends upward from the ceiling of the vacuum heating furnace 5, and an upper end of the bellows 30 is connected to a support seat 32 provided at an upper end thereof. The airtightness of the vacuum heating furnace 5 is determined by the support tube 31, the bellows 30, and the heat-resistant glass window 27 at the lower end of the lamp house 25.
And the inside of the lamp house 25 is placed outside this airtight.

A column 33 is erected on the support seat 32, and a ceiling member 34 of the lamp house 25 is connected to a guide cylinder 35 movably fitted to the column 33. An electric motor 3 having a small gear 37 is provided on a support arm 36 provided at an upper end of a support 33.
8 and a large gear 39 are supported, and the small gear 37 and the large gear 39 are connected by a toothed belt 40. A screw rod 41 rotatably connected to the center of the lamp house ceiling member 34 is screwed into a center hole of the large gear 39. The pipes 42, 43, 44 of the working head 15 leading to the supply / exhaust pipe 20, the cooling water inflow pipe 22, and the outflow pipe 23.
Passes through the interior of the lamp house 25 and its ceiling member 34
Through to the outside world.

As shown in FIG. 3, the movable electric heater 10 has a cooling water jacket 45 on the upper surface, and one end is supported on a rotating shaft 46 which passes through the ceiling of the vacuum heating furnace 5 in an airtight manner.
A crank 47 provided at an outer part of the rotating shaft 46 is connected to a piston rod 49 of an air cylinder 48. Cooling water supply pipe 51 and discharge pipe 52 communicating with a conducting wire 50 for supplying heating power to the movable electric heater 10 and a water jacket 45.
Is airtightly passed through the center of the rotating shaft 46 and is led to the outside.

In manufacturing the PDP, first, the front substrate 2
And a frit adhesive is sandwiched between the peripheral edges of the rear substrate 3 and clipped, and a small hole 4 is formed on the rear substrate 3 as shown in FIG.
The chip tube 4 is placed so as to coincide with 1 and is put into the heating furnace 5 shown in FIG. At this time, the working head 15 and the lamp house 25 are pulled up, and the movable electric heater 10 is positioned above the chip tube 4 instead.

While maintaining the inside of the furnace at atmospheric pressure, each heater 6-
When the furnace is heated to about 450 ° C. by applying a current to 10, the frit adhesive melts and the front substrate 2 and the rear substrate 3 are sealed between the peripheral portions. The tip tube 4 is also a movable electric heater 1
0 so that the frit adhesive 58
Is bonded to the back substrate 3 by melting. At this time, since the upper surface of the movable electric heater 10 is cooled by the cooling water jacket 45, it is possible to prevent the work head 15 located above the heater from being heated and adversely affecting the packing 17 and the like.

When the sealing between the substrates and the welding of the chip tube 4 are confirmed, the temperature in the furnace is lowered to about 350 ° C., the valve 11 is opened, and the vacuum exhaust system 12 is operated to remove the occluded gas in the space between the substrates. Discharge enough. When this is completed, the temperature in the furnace is further lowered, and when the temperature reaches about 200 to 250 ° C., the air cylinder 48 is made differential to move the movable electric heater 10 away from the position above the chip tube 4, and the electric motor 38 is replaced instead. Is driven to lower the lamp house 25. Then, the chip tube 4 enters the relay chamber 16 through the opening 18 of the working head 15, and the packing 17 on the lower end face of the working head 15
The chips 5 and 25 surround the chip tube 4 and are reliably pressed against the back substrate 3 with an appropriate pressing force.

When the outside air is introduced into the furnace with the leak valve 13 opened, the working head 15 is strongly pressed against the back substrate 3 due to the pressure difference between the furnace and the relay chamber 16, and a complete airtight state is established. The on-off valve 53 is opened, and the furnace temperature is further lowered while continuing the evacuation of the inside of the PDP assembly 1 for about 5 seconds.
When the temperature reaches about 0 ° C., the on-off valve 53 is closed to stop the exhaust of the PDP assembly 1, and the on-off valve 54 is opened instead to open the PD.
A discharge gas is introduced into the P assembly 1 to a predetermined pressure.

Then, when the heat ray source 28 is turned on, the heat rays are concentrated on the tip portion of the tip tube 4 by the reflecting mirror 29, and this is heated to several hundred degrees Celsius, and the end of the tip tube is instantly sealed. Finally, the valve 54 is closed to stop the supply of the discharge gas,
After opening the valve 55 and returning the inside of the working head 15 to atmospheric pressure,
The electric motor 38 is operated to raise the lamp house 25 and the work head 15, and the furnace 5 is opened to complete the completed PDP assembly 1.
To the outside world.

[0030]

As is apparent from the above description, according to the present invention, the steps of attaching a working head for exhaust and discharge gas introduction to the tip tube of the PDP assembly, sealing the tip tube, and sealing are performed. After finishing, there is no need to remove any remaining portion of the tip tube from the working head. As a result, the number of processes is reduced, the productivity is improved, and the accident caused by the tip tube during the work is almost eliminated, so that the product yield is improved, and it is possible to contribute to the automation of all the processes and the flow operation. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a working head and a lamp house according to an embodiment of the present invention.

FIG. 2 is an overall configuration diagram of the embodiment.

FIG. 3 is a vertical sectional view of the movable electric heater in the embodiment.

FIG. 4 is a longitudinal sectional view showing an attached state of the tip tube in the embodiment.

FIG. 5 is a longitudinal sectional view showing a state of attachment of a tip tube and a state of attachment of a working head to the tip tube in a conventional PDP assembly.

FIG. 6 is an overall configuration diagram of a conventional PDP manufacturing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 PDP assembly 3 Back substrate 4 Chip tube 5 Vacuum heating furnace 6-9 Electric heater 10 Movable electric heater 12 Vacuum exhaust system 15 Work head 16 Relay room 17 Annular packing 18 Opening 19 Heat-resistant glass window 20 Supply / exhaust pipe 21 Cooling water jacket Reference Signs List 24 rod 25 lamp house 26 spline 27 heat-resistant glass window 28 heat ray radiation source 29 reflector 30 bellows 33 support post 38 motor 41 screw rod 42 supply / exhaust line 45 cooling water jacket 46 rotation axis 47 crank 48 air cylinder

Continuation of the front page (51) Int.Cl. ⁶ identification code FI H04N 5/66 101 H04N 5/66 101Z (58) Investigated field (Int.Cl. ⁶ , DB name) H01J 9/40 G09F 9/30 309 H01J 9/385 H01J 9/26 H01J 11/02 H01J 17/18

Claims (6)

(57) [Claims] 1. A vacuum heating furnace which is configured to accommodate a plasma display panel assembly having a chip tube planted on its rear substrate, has a heating heater therein, and is connected to a vacuum exhaust system. A lamp house is supported inside the heating furnace so as to be able to advance and retreat by movement in a direction perpendicular to the rear substrate, and a working head supported on a surface of the lamp house facing the rear substrate. The working head has a relay chamber inside which is connected to a vacuum exhaust system and a discharge gas supply source, and has a heat-resistant glass window on the surface on the lamp house side for hermetically closing the relay chamber. A side surface has an opening through which the chip tube can be introduced into the relay chamber, and an annular packing surrounding the opening and allowing airtight contact with the back substrate. The lamp house has heat inside. An apparatus for manufacturing a plasma display panel, comprising: a radiation source and a reflector for concentrating a heat ray of the radiation source through the heat-resistant glass window in the relay room. 2. The plasma display panel manufacturing apparatus according to claim 1, wherein a cooling water jacket for cooling the annular packing is provided inside the working head. 3. The lamp house according to claim 1, wherein a surface facing the work head is constituted by a heat-resistant glass window, and an inside of the lamp house is airtightly shut off from an inner space of the heating furnace. Plasma display panel manufacturing equipment. 4. A bellows is provided surrounding the lamp house, one end of the bellows is hermetically connected to a periphery of a window provided on a wall of the heating furnace, and the other end is a periphery of a heat-resistant glass window of the lamp house. The plasma display panel manufacturing apparatus according to claim 3, wherein the plasma display panel manufacturing apparatus is hermetically coupled to the panel. 5. An advanced position between the work head and the back substrate when the work head is located away from the back substrate together with the lamp house in the heating furnace; 2. The plasma display panel manufacturing apparatus according to claim 1, wherein a movable heater is provided so as to be able to advance and retreat between a retracted position which does not hinder the contact with the rear substrate. 6. The plasma display panel manufacturing apparatus according to claim 1, wherein the movable heater has a cooling water jacket for cooling a surface opposite to the rear substrate.