TWI588101B - Apparatus and methods for providing a clean glass-making environment - Google Patents

Description

Apparatus and method for providing a clean glass manufacturing environment [Cross-reference to related applications]

The present application claims priority to U.S. Provisional Application No. 61/563,927, filed on Nov. 28, 2011, the content of which is hereby incorporated by reference.

This invention relates to apparatus and methods for making glass, and more particularly to apparatus and methods for making glass segments by a pull-down process.

Due to its ability to produce excellent glass surface quality, the melting process of glass sheet production has become a preferred method of forming glass. In the melt process, the glass overflows the shaped body to fuse the two separate melt streams into one glass ribbon and thereby maintain the surface quality of the two outer surfaces. Glass surface quality is extremely important to customers who use glass to manufacture displays such as flat panel displays, liquid crystal displays (LCDs), OLED displays, plasma displays, and field emission displays. Even small surface defects can cause delay differences or other problems that end users (eg, television viewers) may consider to be defects (eg, Dark spots or highlights in the picture). A typical liquid crystal cell gap is in the range of <5 μm, so even a surface artificial factor of 1 μm causes a 20% change in the path length of light from the surrounding area. In extreme cases, surface defects may be large enough to completely bridge the cell gap, causing a short circuit. High quality LCD panels require excellent surface quality of the glass components. The effects of surface defects are extremely significant for large-scale (Gen) size panels (eg, 8th and 10th generations) in which even one defect can cause the entire sheet to be unusable. One type of this glass defect is referred to as "onclusion".

The attached fused particles are particle type defects that adhere to the surface of the molten glass during the formation of the glass ribbon and may be partially embedded in the glass. Adhesion fusion particles are a general term for the nature of defects and may have many sources. A fusion draw machine (FDM) for making glass is open at the bottom and air is freely circulated upward from the bottom of the draw machine. This air can transport the particulate matter (the particulate matter causes defects) upward and transfer it to the molten glass. Additionally, the general refractory components of the FDM itself may be detached or agitated by vapor or temperature, thereby creating particulate matter that entrains the air stream within the FDM or otherwise forms defects on the glass surface. All of these particulate materials conform to the class of adherent fused particles and cause glass loss. The location of such particulate matter on the surface of the sheet makes the attachment of the fused particles an important class of defects.

Attempts have been made to reduce the amount of air that floats upward from the bottom of the FDM by the so-called chimney effect, thereby attempting to reduce the amount of adhering fused particles. In general, such attempts involve controlling the pressure in the FDM.

The inventors have discovered that merely controlling the pressure within the FDM is insufficient to maintain a low level of adherent fused particles on the glass surface. Additionally, the manner in which the pressure within the FDM is controlled affects the pressurization to reduce the ability to adhere to the fused particles while maintaining thickness control (i.e., maintaining a low thickness variation across the glass width). In particular, the inventors have discovered that pressurization at the point of forming a clean air environment within the FDM at the point where adhesion of the fused particles is likely to be formed is a robust and sustainable way to achieve a reduction in adherent fused particles. A clean air environment can be formed in the FDM by appropriately selecting a device through which the transfer gas is pressurized to press the FDM, a quality of the gas itself according to the particulate matter contained in the gas, and a position at which the gas is delivered to the FDM, the device, This quality and each of the locations affects the ability to reduce the attachment of fused particles. The present disclosure is directed to an apparatus and method for increasing the pressure within an FDM, and thereby reducing adhesion of the fused particles while maintaining thickness control, suitably (i.e., when forming a clean air environment).

Additional features and advantages will be set forth in the <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; Those skilled in the art will recognize some of these features and advantages. The above general description and the following detailed description are merely illustrative of the various aspects of the invention, and are intended to provide an overview or a framework to understand the nature and features of the invention as claimed.

The drawings are included to provide a further understanding of the principles of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiments and are used to illustrate the principles and operation of the invention. It should be understood that in this specification and The various features disclosed in the figures can be used in any or all combinations. By way of non-limiting example, as set forth in the following aspects, various features may be combined with one another: according to a first aspect, a drop-down glass manufacturing apparatus is provided, the apparatus comprising: a casing; a shaped body, the shaped body setting In the outer casing; an inlet pipe disposed to convey molten glass to the shaped body; and a conduit having an outlet, and the conduit is configured to deliver fluid to the outer casing, whereby the outer casing can be pressurized, wherein the conduit is Made of a material that does not react or is not corroded at temperatures in the FDM above the shaped body.

According to a second aspect, there is provided apparatus according to aspect 1, wherein the conduit is made of ceramic, glass ceramic, glass, platinum, rhodium, palladium, rhodium or nickel.

According to a third aspect, there is provided apparatus according to Aspect 1 or Aspect 2, the apparatus further comprising a source of gas coupled to the conduit, wherein the source of gas is configured to deliver a level of airborne particulate cleanliness class 100 or cleaner.

According to a fourth aspect, there is provided an apparatus according to any one of Aspect 1 to Aspect 3, wherein the conduit is located at the same height as the shaped body.

According to a fifth aspect, there is provided an apparatus according to any one of Aspect 1 to Aspect 4, wherein the outer casing is a muffle chamber including a muffle door at the bottom of the muffle chamber The glass formed by the shaped body exits the muffle chamber via the muffle door, wherein the outlet of the conduit is located within the muffle chamber and outside the muffle door.

According to a sixth aspect, there is provided apparatus according to aspect 5, wherein the muffle door comprises a front panel facing the root, wherein the front panel is made of a material having a high thermal conductivity, and the apparatus further comprises a muffle door chamber, The muffle door chamber is disposed on one side of the front panel, and the root is disposed on the side of the front panel opposite the side.

According to a seventh aspect, there is provided a method of producing a glass segment, the method comprising the steps of: flowing molten glass above a shaped body disposed within a casing such that molten glass flows downwardly from the shaped body in the form of a belt; The conduit delivers fluid to the outer casing to pressurize the outer casing, wherein the conduit is made of a material that does not react or is not corroded at temperatures above the shaped body in the FDM.

Passing the tape out of the outer casing; and cutting the tape to form a glass segment.

According to an eighth aspect, the method of aspect 7, wherein the conduit is made of ceramic, glass ceramic, glass, platinum, rhodium, palladium, iridium or nickel.

According to a ninth aspect, there is provided a method of aspect 7 or aspect 8, wherein the flow system air-floating particles are cleaned to a grade 100 or cleaner gas.

According to a tenth aspect, there is provided a method of any one of Aspect 7 to Aspect 9, the method further comprising the step of delivering a fluid at a height of the shaped body.

According to an eleventh aspect, there is provided a method of any one of aspect 7 to aspect 10, wherein the outer casing has a muffle chamber of a muffled door, the belt exiting the muffle chamber via the muffle door, and The method further includes the following steps Step: Transfer fluid in the muffle chamber and outside the muffle door.

According to a twelfth aspect, the method of aspect 11, wherein the muffle door comprises a front panel facing the root, wherein the front panel is made of a material having a high thermal conductivity, and the apparatus further comprises a muffle door chamber, The muffle door chamber is disposed on one side of the front panel, and the root is disposed on the side of the front panel opposite the side.

According to a thirteenth aspect, a pull-down glass manufacturing apparatus is provided, the apparatus comprising: an outer casing; a shaped body disposed within the outer casing; an inlet pipe configured to convey molten glass to the formed body; and a conduit The conduit has an outlet, and the conduit is configured to deliver fluid to the outer casing, whereby the outer casing can be pressurized; and a source of gas coupled to the conduit, wherein the gas source is configured to deliver an empty particle cleanliness class 100 or cleaner gas.

According to a fourteenth aspect, there is provided an apparatus according to aspect 13, wherein the conduit is located at the same height as the shaped body.

According to a fifteenth aspect, there is provided apparatus according to aspect 13 or aspect 14, wherein the outer casing is a muffle chamber comprising a muffle door at the bottom of the muffle chamber formed by the shaped body The glass exits the muffle chamber via the Mavage door, with the outlet of the conduit located inside the muffle chamber and outside the Ma Fu door.

According to a sixteenth aspect, there is provided a method of manufacturing a glass segment, the method comprising the steps of: flowing a molten glass over a shaped body disposed within the outer casing to melt The molten glass flows downwardly from the shaped body in the form of a belt; the fluid is delivered to the outer casing via a conduit to pressurize the outer casing, wherein the flow system floats the particles to a level 100 or cleaner gas; the strip is discharged out of the outer casing; and the cutting belt is Form a glass segment.

According to a seventeenth aspect, the method of aspect 16 is provided, the method further comprising the step of delivering a fluid at a height of the shaped body.

According to an eighteenth aspect, a method of aspect 16 or aspect 17, wherein the outer casing has a muffle chamber of a muffled door, the belt exits the muffle chamber via the muffle, and the method further comprises the following Step: Transfer fluid in the muffle chamber and outside the muffle door.

4‧‧‧glass ribbon

6‧‧‧ thickness

8‧‧‧Stainless glass

10‧‧‧FDM

12‧‧‧Maff room

13‧‧‧ arrow

14‧‧‧ Lower casing

16‧‧‧ opening

20‧‧‧Muffle door shell

22‧‧‧ front panel

24‧‧‧Muffle door chamber

26‧‧‧ tube

28‧‧‧ Fluid source

30‧‧‧Formed body

32‧‧‧ Contraction side

34‧‧‧ Root

36‧‧‧ Entrance

40‧‧‧ catheter

42‧‧‧Export

44‧‧‧ Fluid source

100‧‧‧Glass manufacturing system

110‧‧‧fusion vessel

112‧‧‧ arrow

115‧‧‧Clarification container

120‧‧‧Mixed container

122‧‧‧Connecting tube

125‧‧‧Transport container

126‧‧‧Solid glass

127‧‧‧Connecting tube

130‧‧‧ downflow tube

140‧‧‧Drawing roller assembly

Figure 1 is a schematic view of a melt drawing machine.

Figure 2 is a graphical representation of the relationship between the number of attached fused particles and the pressure in the muffle shell.

Fig. 3 is a schematic diagram showing the relationship between the amount of thickness variation and the pressure in the muffle.

Figure 4 is a schematic view of a glass manufacturing facility.

In the following detailed description, exemplary embodiments of the present invention However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments. In addition, well-known devices, methods, and materials may be omitted. Description of the material in order to avoid obscuring the description of the various principles of the invention. Finally, in any applicable case, the same component symbols refer to the same components.

The directional terminology (eg, up, down, right, left, front, back, top, bottom) as used herein is made with reference only to the figures as illustrated, and is not intended to imply an absolute orientation.

Unless expressly stated otherwise, it is not intended that any of the methods set forth herein require that the steps of the method be performed in a particular order. Thus, the order in which the method claims are not actually described in the steps of the method, or in the case of the claims or the description. This applies to any possible basis for non-clear interpretation, including: logical matters relating to the arrangement of steps or operational flows; common meanings derived from grammatical organization or punctuation; number or type of embodiments described in the specification .

As used herein, the singular forms """ Thus, for example, reference to "a component" includes the aspect of having two or more such components unless the context clearly dictates otherwise.

The present disclosure relates to apparatus and methods for pressurizing while forming a clean air environment within a fusion draw machine (FDM) at points where adhesion of fused particles is likely to be formed, and the apparatus and method provide for obtaining adhesion fusion A robust and sustainable way to reduce particles.

One way to create a clean air environment in an FDM involves gas delivery via the device, which itself does not produce particles that will form adherent fused particles. This can be done by appropriate selection of the material used to make the catheter The gas is delivered to the FDM via the conduit to pressurize the area of the FDM. The entire catheter need not be made of this material as long as the fluid delivery lumen of the catheter is made of this material. The present inventors have discovered that a conduit made of a high melting point material, when in contact with a nitrogen-rich or oxygen-rich fluid source, is not present in the vicinity of the shaped body at temperatures typically present in the FDM (e.g., 900 ° C to 1300 ° C). A reaction, degradation or corrosion that would result in the generation of particles would occur, the conduit being very suitable for transporting gas without the conduit itself producing particles that would cause adhesion of the fused particles. For example, the conduit can be made of ceramic, glass ceramic or glass. Also, the conduit can be made of a metal such as platinum, rhodium, ruthenium, palladium or nickel.

A second way to create a clean air environment in FDM involves the use of a gas that does not itself include a large amount of particles that cause attachment of the fused particles. The inventors have discovered that it conforms to the US Federal Standard 209E by the name "Airborne Particulate Cleanliness Classes" (available from Northwest Highway 60056, Mount Prospekt, Illinois, USA). Airborne Particle Cleanliness Level 100 (M3.5) measured by the Institute of Environmental Sciences and Technology, 940 East Northwest Highway (Mount Prospect, IL, 60056, USA) A cleaner gas is suitable to increase the pressure within the FDM, which is not itself a source of particles that cause adhesion of the fused particles.

A third way to create a clean air environment in the FDM involves the location of the gas delivered to the FDM. More specifically, the inventors have discovered that in the muffle chamber but outside the muffle, delivery of gas to the FDM at the level of the shaped body results in a low level of adherent fused particles.

The fusion of the clean air environment will be explained with reference to Figure 1. An embodiment of a machine (FDM). The FDM 10 includes an upper casing or a muffle chamber 12 and a lower casing 14, in which the glass ribbon 4 is formed, through which the glass ribbon 4 is drawn and thermally adjusted until the glass ribbon 4 is under The FDM 10 exits the opening 16. The glass sheet 8 is then separated from the lower end of the strip 4 using techniques known in the art. Although the sheet 8 is illustrated as being self-contained in 4 divisions, the strip 4 of any length may be formed before the glass sheet 8 is separated from the remainder of the strip 4 (e.g., when the glass is wound). Therefore, it should be understood that the "glass sheet" is used in the specification for convenience of reference only, and the term may also include a wrapped glass segment.

The muffle chamber 12 surrounds the formed body 30 forming the glass ribbon 4. The formed body 30 receives molten glass from the inlet pipe 36. The glass flows over the opposite contracting side 32 of the shaped body 30 in two separate streams which are recombined at the root 34 of the shaped body 30 to form a glass ribbon 4 having a thickness of 6.

A pair of muffle door housings 20 are located at the bottom of the muffle chamber 12, and the pair of muffle door housings 20 are used to control the thickness across the glass ribbon 4 (i.e., in the direction of entering and exiting the plane of Figure 1). 6 changes. A muffle door housing 20 is provided on each side of the belt 4, whereby the muffle door housing 20 is formed with an opening through which the glass ribbon 4 extends to the lower outer casing 14. Each of the muffle door housings 20 has the same structure, and thus only one muffle door housing 20 will be described in detail. Similarly, the various principles can be illustrated in conjunction with one of the illustrated MacPherson housings 20, while it is understood that the same principles can be equally applied to other Mavage door housings 20. The muffle door housing 20 is disposed to face the formed body 30, and faces the glass ribbon 4 when the glass ribbon 4 has a viscosity higher than the softening point of the glass ribbon 4. The muffle door housing 20 includes a front panel 22, a muffle door chamber 24, and a plurality of tubes 26. Each of the tubes 26 includes an outlet within the muffle door chamber 24.

The front panel 22 is formed of a material having a constant high electrical conductivity, a low thermal expansion rate, and a high emissivity under time and temperature changes. Preferably, the front panel 22 is formed from a silicon carbide crucible, and the back surface of the front panel 22 does not contact any support structure that may cause thermal discontinuities on the face of the panel, except for the demarcated edges.

Fluid source 28 is coupled to deliver fluid to tube 26. Although only one tube 26 is illustrated on each side of the shaped body 30, there are typically a plurality of tubes 26 disposed along the width of the glass ribbon 4; any suitable number of tubes can be used on each side of the shaped body 30. 26, wherein the number generally depends on the width of the glass ribbon 4. The fluid can be, for example, air, compressed air, any other suitable gas. Throughout the specification, the terms "air" or "air flow" are used for convenience, but such terms are intended to include all suitable types of gases or other fluids. Fluid is delivered from fluid source 28 via tube 26 into Marvel gate chamber 24 to cause fluid to impinge on front panel 22 and locally control the temperature of front panel 22. The local temperature at the fixed point on the front panel 22 then affects the temperature of the adjacent portion of the glass ribbon 4, thereby affecting the viscosity of the adjacent portions of the glass ribbon 4 and the corresponding thickness. The flow of fluid through each tube 26 can be individually adjusted in a manner known in the art to control the thickness gradient across the strip 4.

In the lower casing 14, there are various structures for moving and/or guiding the glass ribbon 4 in the downward direction, but such structures are not illustrated for the purpose of simplification of illustration. Again, there may be various other structures present in the outer casing 14 for heat loss of the thermal conditioning belt 4 or the control belt 4 as the belt 4 moves through the outer casing 14.

Within the muffle chamber 12 and the lower outer casing 14, there are various openings that allow air to leak from the FDM 10. Such openings may include (eg, for electrical connections, for fluid connections, for accessing and/or accessing equipment within the FDM 10, For water cooling crucibles, for electric resistance heaters, coil windings for heat coupling use and/or for openings 26 and/or unwanted cracks or holes. Even when a seal is provided for the device inserted through the desired opening, there may still be a leak at the seal that allows fluid to flow out of the FDM 10. Because of the air leaking from the FDM 10 and the thermal gradient within the FDM 10 itself, there is a flow that flows upward in the direction of the arrow 13. This stream draws air through the bottom opening 16 and may cause the air to carry particles from the outer region of the FDM 10 or from the source of particulates within the lower outer casing 14. If the particles travel up through the FDM 10 to the area of the muffle door housing 20, the particles may adhere to the glass ribbon 4 or otherwise be embedded within the glass ribbon 4, thereby forming the adherent fused particles as set forth above. It is therefore desirable to minimize the upflow in the FDM 10, particularly in the region of the Marvel door housing 20.

One way to minimize flow in the FDM 10, particularly in the region of the Mavage door housing 20, is to pressurize the muffle chamber 12. However, merely pressing the muffle chamber 12 is not sufficient to reduce the attachment of the fused particles. In addition, a clean air environment should be formed. A pressurized clean air environment can be formed within the muffle chamber 12 by appropriate selection of equipment through which gas is delivered to pressurize the muffle chamber 12; the quality of the gas itself; and the location of the gas delivery, Each of the device, the quality, and the location affects the ability to reduce the attachment of the fused particles.

One way to create a clean air environment in an FDM involves gas delivery via the device, which itself does not produce particles that will form adherent fused particles. This can be accomplished by appropriate selection of the material used to make the catheter, through which gas is delivered to the FDM to pressurize the area of the FDM. The entire catheter need not be made of this material as long as the fluid delivery lumen of the catheter is This material can be made. The present inventors have discovered that a conduit made of a high melting point material, when in contact with a nitrogen-rich or oxygen-rich fluid source, is not present in the vicinity of the shaped body at temperatures typically present in the FDM (e.g., 900 ° C to 1300 ° C). A reaction, degradation or corrosion that would result in the generation of particles would occur, the conduit being very suitable for transporting gas without the conduit itself producing particles that would cause adhesion of the fused particles. For example, the conduit can be made of ceramic, glass ceramic or glass. Also, the conduit can be made of a metal such as platinum, rhodium, ruthenium, palladium or nickel. The actual situation is that materials with a melting point higher than the highest expected temperature in the FDM should be chosen; however, this requirement is the lowest. Additionally, as noted above, the selected material should be a material that does not react, degrade, or corrode when contacted with a nitrogen-rich or oxygen-rich fluid source, as such reactions, degradation, or corrosion will result in the formation of adherent fused particles. particle. By using a conduit that does not itself produce particles that will form adherent fused particles, the device for conditioning and/or filtering the fluid to be delivered (to ensure that the fluid does not include particles that result in the formation of adherent fused particles) can be placed in the FDM Outside the high temperature environment. This not only extends equipment life, but it also makes it easier to perform maintenance services on the equipment.

Referring to Figure 1, a catheter 40 having an outlet 42 extends into the muffle chamber 12, according to one embodiment. The other end of the conduit 40 is disposed outside of the high temperature environment within the FDM. An outlet 42 is disposed within the muffle chamber 12 to deliver gas from the fluid source 44. The conduit 40 can be made of, for example, ceramic, glass ceramic, glass, platinum, rhodium, ruthenium, palladium or nickel. Although only one conduit 40 is illustrated on each side of the shaped body 30, any suitable number of such conduits can be used to effect the desired pressurization of the muffle chamber 12. The duct 40 may be disposed at various points along the width direction of the muffle chamber 12 (extending perpendicular to the plane of Fig. 1). Additionally, the conduit 40 can be disposed at the end of the muffle chamber, that is, in a direction parallel to the width of the muffle chamber 12. The gas pressurized into the muffle chamber 12 pressurizes the muffle chamber 12 to reduce the effect of the upward flow in the direction of the arrow 13 and thereby reduce the probability of particles in the ascending flow forming the fused particles on the glass ribbon 4. In addition, since the apparatus for delivering pressurized air (i.e., the conduit 40) is made of a material that does not itself form particles that adhere to the fused particles, a clean air environment is formed within the muffle chamber 12.

A second way to form a clean air environment in FDM involves pressurizing the FDM with a gas that does not itself include a large amount of particles that cause attachment of the fused particles. The present inventors have discovered that a gas that meets the cleanliness rating of Class 100 (M3.5) or cleaner, as measured by US Federal Standard 209E, is suitable for increasing the pressure within the FDM, which gas itself does not cause adhesion. A source of particles that fuse the particles. The fluid source 44 is configured to deliver the cleanliness (i.e., a gas having a Class 100 (M3.5) or cleaner air clean rating) to the conduit 40. Fluid source 44 can be, for example, an air compressor, pump, fan, supercharger, or other air treatment device having a sufficient degree of high efficiency particle attraction (HEPA) filtration at the outlet of fluid source 44 for delivery. The cleanliness of the gas. Alternatively, fluid source 44 need not include a filtration device at the outlet of fluid source 44 if a gas system suitable for cleanliness is readily available. Although fluid source 44 is illustrated as being coupled to only one conduit 40, one such fluid source 44 can be coupled to a plurality of conduits 40 that are as practical as possible to deliver a desired amount of pressurized gas to the muffle chamber 12. For example, a fluid source 44 can be coupled to the conduit 40 on either side of the shaped body 30. Moreover, although fluid source 44 is illustrated as being separated from fluid source 28, this need not be the case. That is, the fluid source 44 can be coupled to the conduit 40 and Both tubes 26 are.

A third way to create a clean air environment in the FDM involves the location of the pressurized gas delivered to the FDM. More specifically, the inventors have discovered that transporting gas to the FDM near the same height as the shaped body in the muffle chamber but outside the muffle chamber results in a low level of adherent fused particles.

According to one aspect of the third way of forming a clean air environment, referring to Fig. 1, a conduit 40 is provided to position the outlet 42 within the FDM 10, substantially at the same height as the shaped body 30. That is, the formed body 30 is disposed within the FDM 10 at a height above the lower opening 16. The supply of air at the height of the shaped body 30 increases the pressure near the root 34 and the side 32, thereby minimizing the amount of particles reaching the glass at the point where the particles can form a fused particle on the glass surface.

According to another aspect of the third way of forming a clean air environment, referring again to Figure 1, the outlet 42 is disposed within the muffle chamber 12 and outside of the muffle door chamber 24.

Supplying air into the muffle door chamber 24 to pressurize the muffle chamber 12 is undesirable. In particular, as the total volume of air in the muffle door housing 20 increases, the pressure in the muffle chamber 12 increases, which promotes a reduction in the level of adherent fused particles, as schematically illustrated in FIG. However, the additional air supplied into the muffle door housing 20 causes the pressure in the muffle door chamber 24 to increase, whereby air leaks into the glass ribbon 4 in an uncontrolled manner, resulting in localized thickness variations, such as the third The figure shows the schematic diagram. That is, the pressure within the muffle door housing 20 (i.e., within the muffle door chamber 24) is used to increase the total within the muffle chamber 12. Thickness changes are negatively affected by pressure. On the other hand, an increase in the level of the attached fused particles is observed when the muffle door chamber 24 is actively emptied to prevent air from leaking into the belt 4. Thus, in order to increase the pressure within the muffle chamber 12 (to reduce adhesion of the fused particles) without increasing the pressure inside the muffle door housing 20 (this increase results in undesirable thickness variations), it may be within the muffle chamber 12 Air is supplied outside the muffle door chamber 24. In addition, this position (outside the muffle door housing in the muffle chamber) minimizes the effects on other airflow units in the muffle.

In order to retrofit existing FDMs to practice the concepts described herein, existing tubes 26 that are not required for thickness control can be used to assist in reducing adherent fusion particles in accordance with the above concepts. In particular, the tubes 26 can be retracted from the starting position of the tubes 26 such that the outlets of the tubes 26 are external to the Mavage chamber 24, but are still within the muffle chamber 12. The fluid from source 28 can then be delivered to the muffle chamber 12 to increase the pressure in the muffle chamber 12. Additionally, without the use of fluid from source 28, fluid source 44 (i.e., a fluid source that delivers 100 grade or cleaner airborne particulate clean grade air) can be coupled to such existing tubes 26, such tubes 26 have The outlets of these tubes 26 themselves are outside the muffle door chamber 24 but are still within the muffle chamber 12. With this arrangement, air having a clean grade of airborne particles of level 100 or cleaner can be delivered to the muffle chamber 12. Thus, the existing tube 26 can be used to assist in creating a clean environment within the FDM 10.

A method of making a glass sheet 8 using the concepts described herein will now be described.

FIG. 4 illustrates an exemplary glass manufacturing system 100 using a melt process, and in the exemplary glass manufacturing system 100, the above concepts can be used to fabricate a glass sheet 8. The glass manufacturing system includes a melting vessel 110 and a clarification vessel 115 (eg, a clarification tube), a mixing vessel 120 (eg, a mixing chamber), a delivery vessel 125 (eg, a bowl cavity), and an FDM 10. A glass material is introduced into the melting vessel 110 as illustrated by arrow 112 and the glass material is melted to form molten glass 126. The clarification vessel 115 includes a high temperature treatment zone (not shown) that receives the molten glass 126 from the smelting vessel 110, and in the high temperature treatment zone, bubbles are removed from the molten glass 126. The clarification vessel 115 is connected to the mixing vessel 120 by a connecting pipe 122. The mixing container 120 is connected to the conveying container 125 by a connecting pipe 127. The delivery container 125 transports the molten glass 126 into the FDM 10 via a downcomer 130 that includes an inlet 36, a shaped body 30, and a pulling roll assembly 140. The molten glass flows from the downflow tube 130 into the inlet 36, which is directed to the shaped body 30. The shaped body 30 includes a recess that receives the molten glass 126, which then overflows and flows down the sides 32 of the formed body 30, and then fuses together at the root 34. The root portion 34 is joined at both sides 32, and at the root portion 34 the two overflow or walls of the molten glass 126 are recombined (e.g., refused) to form a glass ribbon 4 by means of a pulling roller Component 140 is pulled down. The details of FDM 10 are as set forth above in connection with Figure 1. It should be noted that while certain details of an exemplary glass manufacturing system are described, shaped bodies and glass manufacturing systems are known in the art, and one of ordinary skill in the art can readily select suitable shaped bodies and/or glass making systems.

Referring back to Figure 1, as the molten glass is delivered to the shaped body 30, FDM is formed by appropriately pressurizing the regions within the FDM 10 to reduce the probability that the particles reaching the glass may form points at which the fused particles are attached. 10 clean air environment. In particular, any one or more of the following concepts may be used alone or in any or all combinations to produce this within the FDM Clean air environment: Gas can be delivered to FDM 10 via conduit 40 to pressurize FDM 10 from a low particulate emissive material (i.e., in contact with a nitrogen-rich or oxygen-rich fluid source) Made of a material (such as ceramic, glass ceramic, glass, platinum, rhodium, ruthenium, palladium or nickel) that is not reactive, degraded or corroded at temperatures (900 ° C to 1300 ° C) that are usually present in FDM; Gas is delivered to the FDM 10 at the same height as the shaped body 30 to pressurize the FDM 10; gas can be delivered to the muffle chamber 12, but outside the muffle door outer casing 24, to pressurize the FDM 10; The FMD 10 gas can have a class 100 or cleaner airborne particle cleanliness rating.

It should be emphasized that the above-described embodiments of the present invention, and in particular, the preferred embodiments of the present invention are only possible examples of the embodiments of the present invention. Many variations and modifications of the above-described embodiments of the invention are possible without departing from the spirit and scope of the invention. All such modifications and variations are intended to be included herein, within the scope of the present disclosure and the scope of the invention, and

For example, although the above description has been made in accordance with the fusion drawing, the slit-drawn body can also be used as the formed body 30.

4‧‧‧glass ribbon

6‧‧‧ thickness

8‧‧‧Stainless glass

10‧‧‧FDM

12‧‧‧Maff room

13‧‧‧ arrow

14‧‧‧ Lower casing

16‧‧‧ opening

20‧‧‧Muffle door shell

22‧‧‧ front panel

24‧‧‧Muffle door chamber

26‧‧‧ tube

28‧‧‧ Fluid source

30‧‧‧Formed body

32‧‧‧ Contraction side

34‧‧‧ Root

36‧‧‧ Entrance

40‧‧‧ catheter

42‧‧‧Export

44‧‧‧ Fluid source

Claims (12)

A pull-down glass manufacturing apparatus comprising: a casing; a forming body disposed in the casing; an inlet pipe disposed to convey molten glass to the forming body; and a conduit having An outlet and the conduit is configured to deliver fluid to the outer casing whereby the outer casing can be pressurized, wherein the conduit is made of a material that is in contact with a nitrogen-rich fluid source or an oxygen-rich fluid source Does not react, degrade or corrode at temperatures in the range of 900 ° C to 1300 ° C. A pull-down glass manufacturing apparatus comprising: a casing; a forming body disposed in the casing; an inlet pipe disposed to convey molten glass to the forming body; and a conduit having An outlet and the conduit is configured to deliver fluid to the outer casing, whereby the outer casing can be pressurized; and a gas source coupled to the conduit, wherein the gas source is configured to deliver an airborne particulate cleanliness level (airborne Particulate cleanliness class) Class 100 or cleaner gas. The device of claim 1, wherein the conduit is made of ceramic, glass ceramic, Made of glass, platinum, rhodium, ruthenium, palladium or nickel. The apparatus of claim 1 or claim 3, further comprising a gas source coupled to the conduit, wherein the gas source is configured to deliver an airborne particulate clean grade 100 or cleaner gas. The apparatus of claim 1 or claim 2, wherein the conduit is located at the same height as the shaped body. The apparatus of claim 1 or claim 2, wherein the outer casing is a muffle chamber, the muffle chamber including a muffle door, the muffle door being located in the muffle chamber At the bottom, the glass formed by the shaped body exits the muffle chamber via the muffle door, wherein the outlet of the conduit is located within the muffle chamber and outside the muffle door. A method of making a glass segment, comprising the steps of: flowing molten glass over a shaped body disposed within a housing such that molten glass flows downwardly from the shaped body in a strip; the fluid is delivered via a conduit to The outer casing pressurizes the outer casing, wherein the conduit is made of a material that does not react at temperatures in the range of 900 ° C to 1300 ° C when in contact with a nitrogen-rich fluid source or an oxygen-rich fluid source, Degrading or corroding; causing the strip to flow out of the outer casing; and cutting the strip to form a glass segment. A method of making a glass segment, comprising the steps of: flowing molten glass over a shaped body disposed within a housing such that molten glass flows downwardly from the shaped body in a strip; the fluid is delivered via a conduit to The outer casing pressurizes the outer casing, wherein the flow system cleans the gas of class 100 or cleaner by air-dried particles; causes the strip to flow out of the outer casing; and cuts the strip to form a glass segment. The method of claim 7, wherein the conduit is made of ceramic, glass ceramic, glass, platinum, rhodium, ruthenium, palladium or nickel. The method of claim 7 or claim 9, wherein the flow system is a floating particle cleansing class 100 or cleaner gas. The method of claim 7 or claim 8, further comprising the step of delivering the fluid at a height of the shaped body. The method of claim 7 or claim 8, wherein the outer casing is a muffle chamber, the muffle chamber having a muffle door, the belt leaving the muffle chamber via the muffle door, and the The method further includes the step of delivering the fluid within the muffle chamber and outside the muffle.