JP2009238380A - Device for manufacturing plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make easy manufacturing of a plurality of species of plasma display panels different in composition of a discharge gas to be sealed in. <P>SOLUTION: A device for manufacturing the plasma display to be used for a discharge gas sealing process includes a carriage, a head for piping coupled with a workpiece, a first vacuum pump, a first joint, a first tube passage connected to the head, the first vacuum pump, and the first joint, and having a branch, a first valve to open/close a flow passage between the branch in the first pipe line and the first vacuum pump, a second valve to open/close the flow passage between the branch in the first tube passage and the first joint, the second joint capable of coupling with the first joint, the second tube passage connected to the second joint, a gas cylinder to eject a discharge gas into the second pipe line, a third valve to open/close the second tube passage, and a vacuum exhaust circuit for exhausting the flow passage connected to both the second valve and the third valve formed by coupling the first joint and the second joint. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a plasma display panel manufacturing apparatus, and more particularly to an apparatus used in a discharge gas sealing process.

  The plasma display panel has an internal space sandwiched between a front plate and a back plate and filled with a discharge gas. The front plate and the back plate are glass substrates on which electrodes are arranged. The manufacturing process of the plasma display panel consists of sealing the peripheral parts of the front plate and the back plate, which are produced separately, with sealing material, evacuating the residual gas from the internal space, and introducing discharge gas into the internal space. Including gas filling. In order to perform evacuation and gas filling, a glass substrate in which air holes are formed in advance is used as a material for the back plate.

  For mass production of plasma display panels, an apparatus that continuously performs sealing, evacuation and gas filling is suitable. This apparatus has a heating furnace with a total length of several tens of meters for melting a sealing material and then evacuating it in a heated state, and a plurality of carriages that move in series with a workpiece to be processed. Is provided. A discharge gas cylinder is mounted on each of the plurality of carriages together with a vacuum pump, and vacuum evacuation for a predetermined time and gas filling at a constant pressure are automatically performed in each carriage (Patent Document 1).

A generally used discharge gas is a Penning gas in which a small amount of xenon (Xe) is mixed with neon (Ne). In addition, helium (He) or argon (Ar) -containing three-component gas (Ne + Xe + He, Ne + Xe + Ar), helium-xenon two-component gas (He + Xe), helium-argon-xenon three-component gas (He + Ar + Xe), xenon Instead, a gas in which krypton (Kr) is mixed with xenon is known.
Japanese Patent Laid-Open No. 11-25862

  In the manufacture of a wide variety of plasma display panels, when conventional devices are used, it is difficult to implement a method for optimizing the composition of the discharge gas for each type. This is because every time the type to be manufactured is switched, an operation of exchanging the discharge gas cylinder must be performed for each of the plurality of carriages, and a large number of discharge gas cylinders must be prepared. The greater the number of trolleys, the greater the labor required for the work, and the greater the number of cylinders required. For example, when an apparatus having 300 carriages is used for the production of four types, 1200 cylinders are required. If the number of varieties increases, more cylinders must be prepared. If multiple types of cylinders are loaded on each cart, the burden of cylinder transshipment work is reduced. However, the trolley must be made large.

  If the method of switching the composition of the discharge gas for each product type is implemented, the luminous efficiency can be further increased within a range in which the plasma display panel of each product type can be stably driven. Different types of discharge cells having different sizes and applied drive waveforms have different drive margins, which are acceptable drive voltages, so that the optimum discharge gas composition is different. For example, when a mixed gas of Ne / Xe is sealed, a gas having a relatively high Xe partial pressure is preferable for a product having a wide driving margin and having a high luminous efficiency. A gas having a relatively low Xe partial pressure, which is excellent in discharge easily, is preferable for a product having a narrow driving margin. The method of sealing discharge gas with the same composition for multiple products with different driving margins must use a gas with a composition suitable for products with a narrow driving margin. It is disadvantageous in making it high.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a manufacturing apparatus useful for a discharge gas sealing process of a plurality of types of plasma display panels having different compositions of the discharge gas to be sealed.

  A plasma display panel manufacturing apparatus that achieves the above-described object is an apparatus used in a discharge gas sealing process, in which a workpiece that is a plasma display panel being manufactured is loaded and moved on a predetermined circulation path, A head for piping connected to a work loaded on a carriage, a first vacuum pump attached to the carriage, a first joint for coupling that moves together with the carriage, and the head attached to the carriage And the first vacuum pump and the first joint, a first pipe having a branch point for the connection, and a flow path between the branch point in the first pipe and the first vacuum pump A first valve that opens and closes, a second valve that opens and closes a flow path between the branch point in the first pipe and the first joint, and a second coupling for coupling that can be connected to the first joint. A hand, a second pipe connected to the second joint, a gas cylinder for discharging discharge gas to the second pipe, a third valve for opening and closing the second pipe, the first joint, and the second A vacuum exhaust circuit for exhausting a flow path connected to both the second valve and the third valve formed by coupling with a joint.

  In a preferred aspect, the evacuation circuit includes a second vacuum pump and a third pipe line in which a valve connected to both the second vacuum pump and the second pipe line and opening and closing the flow path is arranged. The

  In another preferred aspect, the evacuation circuit includes the first vacuum pump, a valve included in the first pipe and opening and closing a flow path between a branch point in the first pipe and the workpiece. The first conduit is composed of a portion from the second valve to the first vacuum pump.

  In another preferred embodiment, the discharge gas sealing device includes a plurality of carts having the same configuration.

  The carriage on which the workpiece is loaded and the gas cylinder filled with the discharge gas can be connected and disconnected by connecting and disconnecting the first joint and the second joint. Since it is not necessary to mount the gas cylinder on the carriage, the gas cylinder can be switched to another gas cylinder without transshipment to the carriage.

  Since the discharge gas sealing device has an evacuation circuit, when the carriage and the gas cylinder are separated from each other, undesired gas mixed in a part of the pipeline in the discharge gas sealing device and residual gas other than the discharge gas are removed from the carriage. And a gas cylinder connected to each other, the discharge gas can be sealed in the workpiece. The second valve and the third valve are closed over a period in which the carriage and the gas cylinder are disconnected. In response to the connection between the first joint and the second joint, the vacuum exhaust circuit exhausts the non-target gas. After exhausting by the vacuum exhaust circuit, the second valve and the third valve are opened.

  According to the present invention, it is possible to manufacture a plurality of types of plasma display panels having different compositions of the enclosed discharge gas without changing the gas cylinders with respect to the carriage that loads and moves the workpiece. In addition, since a part of the pipeline from the gas cylinder to the work can be exhausted with the carriage and the gas cylinder connected, when the carriage and the gas cylinder are separated, a part of the pipeline is outside air. Even if it is exposed to (environmental atmosphere), it is possible to prevent unnecessary substances from being mixed into the workpiece by sealing the discharge gas after exhaust.

  A discharge gas sealing apparatus 1 exemplified as an embodiment of the present invention in FIGS. 1 and 2 is equipment for manufacturing a plasma display panel that continuously performs sealing, evacuation, and gas sealing. FIG. 1 shows the outline of the overall configuration of the discharge gas sealing device 1 as viewed from above, and FIG. 2 shows the configuration of the main part.

  In FIG. 1, the discharge gas sealing device 1 includes an annular track 4 that defines a circulation path, a heating furnace 5 that extends along the track 4, a plurality of carriages 10 that are guided by the track 4, and a position adjacent to the track 4. A discharge gas supply unit 30 that is fixedly arranged and a control unit 60 that is a controller for controlling the discharge gas sealing device 1 are provided. The heating furnace 5 has a heating area, a constant temperature area, and a slow cooling area. Each carriage 10 is loaded with a workpiece to be processed before it reaches the entrance of the heating furnace 5. Sealing and evacuation are performed while the work loaded on the carriage 10 passes through the inside of the heating furnace 5. Thereafter, gas is sealed by the discharge gas supply unit 30, and then a process for completely sealing the internal space of the work is performed by a mechanism (not shown).

  The discharge gas supply unit 30 is disposed in the vicinity of the outlet of the heating furnace 5 and has a plug 52 as a second joint that is a part of a coupler for pipe connection with the carriage 10. And the socket 51 as a 1st coupling which can be connected with this plug 52 is attached to each cart 10 directly or indirectly via piping. The plug 52 and the socket 51 can be easily attached and detached. Each carriage 10 is controlled to stop at a position where the socket 51 and the plug 52 face each other. After the carriage 10 is stopped, the socket 51 and the plug 52 are connected automatically or manually, and after the unintended gas remaining in the pipe line near the connected socket 51 and the plug 52 is exhausted, the discharge gas is discharged. Encapsulation is performed.

  When the discharge gas is sealed in the workpiece and the internal space of the workpiece is sealed, the carriage 10 separated from the discharge gas supply unit 30 moves to a position for reloading the workpiece. The cart 10 loaded with a new workpiece instead of the workpiece filled with the discharge gas goes to the heating furnace 5. A drive system (not shown) for moving the carriage 10 is controlled by the control unit 60.

  In this example, the configuration of the plurality of carriages 10 is the same. In FIG. 2, one truck 10 is drawn as a representative. With reference to FIG. 2, the structure of the principal part of the discharge gas sealing apparatus 1 is demonstrated in detail.

  In FIG. 2, the carriage 10 has a multi-stage work support portion 11 that passes through the inside of the heating furnace 5. In the figure, a work 70 is mounted on each of the three shelves. The work 70 is a front plate and a back plate that are stacked and temporarily fixed with clips. These plates sandwich an annular seal material. In the figure, the work 70 is arranged so that the outer surface of the back plate to which the glass chip tube (also referred to as an exhaust pipe) 75 is attached faces upward, but the arrangement is not limited to this. The arrangement may be such that the outer surface of the back plate faces downward. A head (also referred to as a vacuum head) 12 for connecting a pipe to the tip tube 75 is attached to each shelf of the work support unit 11. The plurality of heads 12 are connected to a first pipe line 23 extending across the inside and the bottom of the heating furnace 5.

  The first pipeline 23 is connected to the first vacuum pump 18 assembled to the carriage 10 and the socket 51, and is branched for this connection. A first valve 25 and a second valve 26 are arranged in the first pipe line 23. The first valve 25 opens and closes the flow path between the branch point 230 and the first vacuum pump 18 in the first pipeline 23, and the second valve 26 opens and closes the flow path between the branch point 230 and the socket 51. To do.

  The discharge gas supply unit 30, which is a fluid circuit for sending the discharge gas to the carriage 10, is connected to the above-described plug 52 that can be connected to the socket 51 of the carriage 10, the second conduit 32 connected to the plug 52, and the second conduit 32. A plurality of gas cylinders 41, 42, 43, 44 for discharging discharge gas, and an evacuation circuit 40 are provided. In the second conduit 32, valves 45, 46, 47, and 48 individually corresponding to the gas cylinders 41, 42, 43, and 44, and a third valve 35 that opens and closes the second conduit 32 in the vicinity of the plug 52 are arranged. Has been. A vacuum pump 37 is connected to the second conduit 32 with a valve 36 interposed. The evacuation circuit 40 includes a second vacuum pump 39 and a third conduit 33 in which a valve 38 is disposed. The third conduit 33 connects the portion of the second conduit 32 between the plug 52 and the third valve 35 to the second vacuum pump 39.

  The exemplary discharge gas supply unit 30 can switch between four types of discharge gases. The gas cylinders 41, 42, 43, and 44 are filled with a mixed gas of Ne / Xe as a discharge gas, and the mixing ratio of Ne / Xe is different between the gas cylinders 41, 42, 43, and 44. The gas cylinders 41, 42, 43, 44 are alternatively selected according to the type of work 70 loaded on the carriage 10. In the figure, two gas cylinders correspond to each of the four types of discharge gas. You may change suitably the number of gas cylinders and the number of types of gas to prepare. The discharge gas is not limited to a mixed gas of Ne / Xe, but may be other two-component gas or a gas in which three or more components are mixed.

  The fluid circuit elements provided in the carriage 10 and the discharge gas supply unit 30 are controlled by the control unit 60 (see FIG. 1) according to a predetermined control program. The control unit 60 obtains information necessary for control in a timely manner from various sensors that indicate the position of the carriage 10 and the pressure in the pipeline and a timer that measures the processing time.

  When the work 70 enters the inside of the heating furnace 5 and a predetermined time elapses, the sealing material is softened and the gap between the front plate and the back plate is made airtight. After the time when it is estimated that the inside of the work 70 has become airtight, the first vacuum pump 18 evacuates the inside of the work 70 through the vent hole formed in the back plate in advance and the tip tube 75 connected thereto. Is started. The exhaust path extends from the tip tube 75 through the head 12 and the first conduit 23 to the first vacuum pump 18. By this evacuation, the gas containing impurities remaining inside the work 70 and the inside of the first pipe 23 is exhausted. The second valve 26 is closed during evacuation.

  While the work 70 moves in the slow cooling area of the heating furnace 5, the sealing material hardens and the sealing between the front plate and the back plate is completed. When the work 70 cooled to a predetermined temperature comes out of the heating furnace 5, the process proceeds to preparation for gas filling while continuing the vacuum evacuation.

  When the gas is sealed, the plug 52 of the discharge gas supply unit 30 in a state where the third bulb 35 and the bulb 38 are closed is connected to the socket 51 of the carriage 10 in an environmental atmosphere. The gas flow path in the vicinity of the coupler 50 is exposed to the outside air until just before the connection, and therefore, this gas flow path is cleaned prior to gas filling. For this purpose, the control unit 60 opens the valve 38 of the vacuum exhaust circuit 40. At this time, the second vacuum pump 39 is already operating. The second vacuum pump 39 exhausts the non-target gas remaining in the flow path from the second bulb 26 of the carriage 10 to the third bulb 35 of the discharge gas supply unit 30 and part of the third conduit 33. The valve 38 is closed when exhausting for a predetermined time when the gas flow path near the coupler 50 is sufficiently evacuated is completed. The arrangement interval and the moving speed of the carriages 10 are selected so that the carriages 10 are stopped over the required time for exhaust and gas filling so that the sequential movement of the carriages 10 is not hindered.

  At the start of gas filling, the first valve 25 is closed, the second valve 26 and the third valve 35 are opened, and the valves 45, 46 corresponding to a selected one of the gas cylinders 41, 42, 43, 44. , 47, 48 are opened. For example, if the gas cylinder 41 is selected, the discharge gas flows from the gas cylinder 41 into the workpiece 70. When the pressure measured by a pressure gauge (not shown) provided in the first conduit 23 reaches a set pressure (for example, 67 kPa), the second valve 26 and the third valve 35 are immediately closed. At this point, the discharge gas filling of the work 70 of the cart 10 ends. The carriage 10 that has been filled with the discharge gas is disconnected from the discharge gas supply unit 30 by automatic or manual disconnection of the coupler 50.

  On the other hand, in the carriage 10 that has finished the discharge gas sealing, the tip tube 75 is sealed with the discharge gas remaining in the first conduit 23. The internal space of the work 70 is completely sealed by the sealing, and the first pipeline 23 is also a closed space. The tip tube 75 may be sealed after gas filling, and may be before or after the connection between the carriage 10 and the discharge gas supply unit 30 is released.

  When the carriage 10 that has been sealed and sealed with gas moves and instead the unsealed carriage 10 stops at the position where the discharge gas supply unit 30 is disposed, the plug 52 is connected to the socket 51 of the unfilled carriage 10, and The discharge gas is sealed in the work 70 in the same procedure as in FIG. This series of operations is repeated in synchronization with the movement of the carriage 10.

  When the type of discharge gas supplied to the carriage 10 by the discharge gas supply unit 30 is switched, the discharge gas remaining in the second pipe 32 of the discharge gas supply unit 30 is vacuumed before starting the first gas filling after the switching. It is exhausted by the pump 37. When exhausting, the valve 36 is opened with the third valve 35 closed and all the valves 45, 46, 47, 48 corresponding to the gas cylinders 41, 42, 43, 44 are closed.

  In the above embodiment, there is a modification in which the carriage 10 takes on the function of the vacuum exhaust circuit 40. This modification is shown in FIG. In the example of FIG. 3, elements corresponding to the example of FIG. 2 are denoted by the same reference numerals as in the example of FIG. 2.

  In FIG. 3, the discharge gas sealing device 2 includes a carriage 10 b having an evacuation circuit 40 b and a discharge gas supply unit 30 b connected to the carriage 10 b via a coupler 50. Although one carriage 10b is illustrated in the figure, the discharge gas sealing device 2 includes a plurality of carriages 10b that move while being guided by an annular track as in the configuration of FIG. The discharge gas supply unit 30b is fixedly disposed at a position adjacent to the track.

  The evacuation circuit 40b provided in the carriage 10b includes a first vacuum pump 18, a valve 27 disposed in the first conduit 23b, and a second valve 26 in the first conduit 23b to the first vacuum pump 18. It consists of parts. The first pipe line 23 b is a flow path having a branch point 230 and is connected to the head 12, the first vacuum pump 18, and the socket 51. The valve 27 is disposed between the head 12 and the branch point 230.

  In evacuation for cleaning the inside of the work 70, the second valve 26 is closed and the first valve 25 and the valve 27 are opened. When this evacuation is finished, the valve 27 is closed and the first valve 25 is also closed once. The second valve 26 remains closed.

  When the coupler 50 is connected for gas filling, the first valve 25 and the second valve 26 are opened with the valve 27 of the carriage 10b and the third valve 35 of the discharge gas supply unit 30b closed. Thereby, the non-target gas remaining in the flow path from the third valve 35 to the second valve 26 is exhausted by the first vacuum pump 18, and the flow path related to the discharge gas sealing is cleaned.

  There are other variations in the configuration of the evacuation circuit for cleaning the coupler 50 and its vicinity. In this configuration, the vacuum pump 37 used when switching the gas type is also used when the coupler 50 is connected. When this modification is employed, a valve is provided at, for example, the position p1 in FIG. 3 so as to minimize the portion of the second pipe 32 through which the residual gas in the coupler 50 flows. It is desirable to define the pipe line 32.

  For automating the coupling of the coupler 50, for example, a pipe connection device disclosed in Japanese Patent Laid-Open No. 5-180382 can be used. If the structure of the socket 51 of the coupler 50 is a structure having a tapered surface 511 that guides the tip of the plug 52 to a concentric position as shown in FIG. 4, the connection between the carriages 10 and 10b and the discharge gas supply parts 30 and 30b. Positioning accuracy is relaxed. The structure in which the plug 52 is screwed into the socket 51 to obtain airtightness with the sealing material 515 is excellent in connection reliability as compared with the structure in which the plug is simply pushed. In order to screw the plug 52, the plug 52 and the socket 51 may be relatively rotated after the plug 52 is guided to the concentric position.

  An unmanned operation of the discharge gas sealing devices 1 and 2 requires an automatic coupling mechanism of the coupler 50, but a configuration in which an operator manually connects and disconnects the coupler 50 may be employed. The valves provided in the discharge gas supply units 30 and 30b are preferably valves that can be automatically controlled. However, all or a part of these valves may be manual valves. A sensor for notifying the controller 60 of the open / close state of the manual valve may be provided, or an operator may perform a switch operation to notify the controller 60 of the open / close state of the manual valve.

  Various changes can be made to the configuration of the discharge gas sealing devices 1 and 2. For example, instead of the tip tube 75, an introduction tube made of a material other than glass may be used to connect the head 12 and the work 70. Further, a technique of closing the vent hole of the back plate with a known frit washer can be applied. A pulling track may be connected to the track 4 to fill the gas on the pulling track. Discharge gas supply parts 30 and 30b can be arranged to be movable. There is no limitation on the number of carriages 10 and 10b. The discharge gas supply units 30 and 30b do not necessarily have to include a plurality of gas cylinders 41, 42, 43, and 44 that store discharge gases having different compositions, and include a single or a plurality of gas cylinders that store at least one kind of discharge gas. It only has to be. This is because the cylinder may be replaced when the type of the discharge gas is switched. Compared to the effort required for cylinder replacement when a gas cylinder is mounted on each of the plurality of carriages 10 and 10b, the labor required for cylinder replacement only in the discharge gas supply units 30 and 30b is small.

It is a figure which shows the outline | summary of the whole structure which looked at the manufacturing apparatus of sealing, exhaust_gas | exhaustion / discharge gas enclosure which concerns on embodiment of this invention from upper direction. It is a figure which shows the structure of the discharge gas enclosure apparatus which concerns on embodiment of this invention. It is a figure which shows the modification of a structure of a discharge gas enclosure device. It is a figure which shows an example of the structure of a coupler.

Explanation of symbols

1, 2 Discharge gas sealing device 4 Track (circulation path)
70 Work 10, 10b Dolly 12 Head 18 First vacuum pump 51 Socket (first joint)
23, 23b First pipe line 230 Branch point 25 First valve 26 Second valve 32 Second pipe line 52 Plug (second joint)
41, 42, 43, 44 Gas cylinder 35 Third valve 40, 40b Vacuum exhaust circuit 60 Control unit (controller)
33 3rd pipe line 511 Tapered surface 50 Coupler

Claims (6)

An apparatus used in a discharge gas sealing process of a plasma display panel,
A truck that carries a workpiece that is a plasma display panel in the middle of manufacture and moves on a predetermined circulation path,
A piping head connected to the workpiece loaded on the carriage;
A first vacuum pump attached to the carriage;
A first coupling for coupling that moves with the carriage;
A first pipe line attached to the carriage, connected to the head, the first vacuum pump and the first joint, and having a branch point for the connection;
A first valve for opening and closing a flow path between a branch point in the first pipe line and the first vacuum pump;
A second valve for opening and closing a flow path between the branch point in the first pipe line and the first joint;
A second coupling for coupling that can be coupled to the first coupling;
A second pipe connected to the second joint;
A gas cylinder for discharging a discharge gas to the second conduit;
A third valve for opening and closing the second conduit;
And a vacuum exhaust circuit for exhausting a flow path connected to both the second valve and the third valve formed by connecting the first joint and the second joint. Display panel manufacturing equipment. When the first joint and the second joint are not connected, the second valve and the third valve are closed, and the vacuum exhaust is performed in response to the connection between the first joint and the second joint. 2. The plasma display according to claim 1, further comprising a controller that causes the circuit to perform evacuation for a predetermined time and performs control for opening the second valve and the third valve after the evacuation by the vacuum evacuation circuit is completed. Panel manufacturing equipment. The vacuum evacuation circuit includes a second vacuum pump and a third pipe having a valve connected to both the second vacuum pump and the second pipe and opening and closing the flow path. 2. An apparatus for manufacturing a plasma display panel according to 1. The evacuation circuit includes the first vacuum pump, a valve that opens and closes a flow path between a branch point in the first pipeline and the workpiece, and the second valve of the first pipeline from the second valve. The apparatus for manufacturing a plasma display panel according to claim 2, comprising a portion up to the first vacuum pump. The first joint is a socket having a tapered surface for guiding the second joint to a concentric position;
The apparatus for manufacturing a plasma display panel according to claim 1, wherein the second joint is a plug having a tip portion that engages with the first joint. The apparatus for manufacturing a plasma display panel according to claim 2, comprising a plurality of carts having the same configuration as the cart.

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