WO2004069757A2 - Appareil de formation de verre a vitre - Google Patents

Appareil de formation de verre a vitre Download PDF

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Publication number
WO2004069757A2
WO2004069757A2 PCT/US2004/002999 US2004002999W WO2004069757A2 WO 2004069757 A2 WO2004069757 A2 WO 2004069757A2 US 2004002999 W US2004002999 W US 2004002999W WO 2004069757 A2 WO2004069757 A2 WO 2004069757A2
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WO
WIPO (PCT)
Prior art keywords
glass
trough
sheet
pipe
molten glass
Prior art date
Application number
PCT/US2004/002999
Other languages
English (en)
Other versions
WO2004069757A3 (fr
Inventor
Richard B. Pitbladdo
Original Assignee
Pitbladdo Richard B
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Pitbladdo Richard B filed Critical Pitbladdo Richard B
Publication of WO2004069757A2 publication Critical patent/WO2004069757A2/fr
Publication of WO2004069757A3 publication Critical patent/WO2004069757A3/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B17/00—Forming molten glass by flowing-out, pushing-out, extruding or drawing downwardly or laterally from forming slits or by overflowing over lips
    • C03B17/06—Forming glass sheets
    • C03B17/064—Forming glass sheets by the overflow downdraw fusion process; Isopipes therefor
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B17/00—Forming molten glass by flowing-out, pushing-out, extruding or drawing downwardly or laterally from forming slits or by overflowing over lips
    • C03B17/06—Forming glass sheets
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B17/00—Forming molten glass by flowing-out, pushing-out, extruding or drawing downwardly or laterally from forming slits or by overflowing over lips
    • C03B17/06—Forming glass sheets
    • C03B17/067—Forming glass sheets combined with thermal conditioning of the sheets

Definitions

  • this invention introduces a precise thermal control system to redistribute the flow of molten glass at the weirs which is the most critical area of the forming process. This thermal control effectively counteracts the degradation of the sheet forming apparatus which inevitably occurs during a production campaign.
  • Another preferred embodiment creates a variable external cross-section which alters the direction and magnitude of the surface tension and body force stresses and thus, reduces the adverse influence of surface tension and body forces on sheet width.
  • the present invention employs a bead guide.
  • the bead guide is an adjustably shaped device located beneath the trough at each end of the trough. This device is easily removable for replacement or modification during a production run.
  • the molten glass flows over and attaches itself to the bead guide.
  • the device is optionally heated.
  • the bead guide provides hydraulic stresses that are in opposition to the surface tension stress and thus reduces the influence of surface tension on the formation of thick beads on the edges of the sheet.
  • a preferred embodiment of the present invention measures the temperature of the glass by immersing thermocouples in the glass, at locations from which any defects caused by the immersion are in the glass that forms the unusable edges of the sheet.
  • FIG 1 illustrates the principle parts of "The Overflow Process” glass sheet manufacturing system.
  • Figure 2A shows a side view of "The Overflow Process" as known in the prior art.
  • Figure 2C shows a cross-section across lines C-C of Figure 2 A, where the glass flow in the downcomer pipe appears in the sheet for "The Overflow Process".
  • Figure 5B shows the glass flow in the downcomer pipe across lines B-B of Figure 5A when a flow distribution device is used.
  • Figure 7A shows the top view of a bowl with side inflow which relocates the quiescent flow zone from the bowl nose to the bowl side in a preferred embodiment of the present invention.
  • FIG 8 illustrates a bowl in "The Overflow Process" as known in the prior art.
  • Figure 9A shows a downcomer pipe feeding the forming apparatus inlet with minimum quiescent flow in a preferred embodiment of the present invention.
  • Figure 9B shows a top view of Figure 9 A.
  • Figure 9C shows a detail of the downcomer pipe to trough inlet pipe connection showing the glass flow pattern in a preferred embodiment of the present invention.
  • Figure 10A shows the flow between the downcomer pipe and the forming apparatus inlet in "The Overflow Process" as known in the prior art.
  • Figure 11 A shows the principle parts of a typical "Overflow Process” manufacturing system.
  • Figure 13 A shows a revised single heating chamber muffle design in a preferred embodiment of the present invention.
  • Figure 13B shows a section of Figure 13A.
  • Figure 14B shows a section of Figure 14 A.
  • Figure 16A shows radiant coolers which effect localized cooling to the molten glass as it passes over the weirs in a preferred embodiment of the invention.
  • Figure 16B shows a section of Figure 16A.
  • Figure 18A shows the forming trough support system as known in the prior art.
  • Figure 20 A show a single shaped compression block on one end of the trough and multiple shaped compression blocks on the other end in a preferred embodiment of the present invention.
  • Figure 20B shows another view of Figure 20 A.
  • Figure 23 G shows a cross-section of the trough design shown in Figure 23 A across lines G-G.
  • Figure 24C shows a cross-section of the trough design shown in Figure 24A across lines C-C.
  • Figure 25D shows another view of Figure 25 A.
  • Figure 27C shows another view of Figure 27A.
  • Figure 27D shows another view of Figure 27 A.
  • Figure 31 A shows how the pressure in the transition zone may be controlled to minimize leakage in a preferred embodiment of the present invention.
  • Figure 38A shows a downcomer pipe with three downward extensions submerged in the inlet pipe glass in an embodiment of the present invention.
  • Figure 38B shows a downcomer pipe with three downward extensions partially submerged in the inlet pipe glass in an embodiment of the present invention.
  • Figure 39B shows the streamlines of glass flow in the embodiment of the present invention shown in Figure 39 A.
  • Figure 43B shows a cross-section of the trough shown in Figure 43 A across lines B-B.
  • Figure 47 A shows mounting for a rotating bead guide in an embodiment of the present invention.
  • Figure 47B shows mounting for a rotating bead guide in an alternative embodiment of the present invention.
  • Figure 52B shows a sectional view of Figure 52A.
  • Figure 54A shows an embodiment of present invention trough support system involving support blocks for the weight of the trough at each end and free-floating compression blocks at each end.
  • Figure 58A shows the inlet end and outlet end forces being equal in an embodiment of the present invention.
  • Figure 58C shows a partial view of Figure 58A.
  • the inlet pipe (8) is preferably shaped to control the velocity distribution of the incoming molten glass flow.
  • the glass sheet forming apparatus which is described in detail in both U.S. Patent No. 3,338,696 and Application Nos. 09/851,627 (filed May 9, 2001, U.S. Patent Publication No. US 2001/0039814) and 10/214,904 (filed August 8, 2002, U.S. Patent Publication No. US
  • FIGS 3 A and 3B show an embodiment of the glass sheet fonriing apparatus (31) with an inflow pipe (8), a flow distribution device (32) (which is a subject of this invention) located at the trough inlet surface, and the glass sheet forming apparatus body (9).
  • the flow distribution device (32) interrupts the glass surface flow and diverts it to the surface in the edge of the sheet. Glass from the center of the downcomer pipe flow stream then comes to the surface of the forming trough to form the surface of the useable portion of the glass sheet (11). Note that ten to twenty percent of the sheet at each edge is normally unusable for various reasons.
  • Figure 6 is an embodiment that shows the axis of the bowl (66) inclined at an angle such that the main process stream passes through the front of the bowl.
  • This active flow (60) entrains the surface glass (61), overcoming the surface tension forces that would normally create a quiescent zone of glass flow located at the bowl nose ( Figure 8).
  • a needle (13) is present to stop glass flow.
  • FIGS. 33B, 34B, 36B, 37B, 39B, 41B, and 42B in this application are calculated using a technology termed "computational fluid dynamics", which uses computers to predict the motion of gases and liquids.
  • the particular product used for the calculations herein was CFD2000®, which is one of several products that are commercially available.
  • Figures 10A through IOC and Figures 33 A and 33B show the prior art, where the downcomer pipe (7) has a flat bottom (94) which is immersed below the free surface of the glass (100) in the inlet pipe (8). There is a quiescent zone (101) between the two pipes which has a continuous vortex (102) which surrounds the bottom of the downcomer pipe (7).
  • Figures 37 A and 37B show a downcomer pipe (357) with a single downward extending tip (351) located off center with respect to the inlet pipe (8).
  • the glass exiting the vortices (370) is further concentrated into zone (26).
  • the invention also contemplates the use of two downward extensions. For each extension, or V shape, two vortices are formed. So, a total of four vortices would be formed if two downward extensions were utilized. The downward extensions would be oriented to concentrate the flow exiting the vortices in either both zones (24) or zone (26) and one zone (24).
  • Figure 12A shows the side view of the forming trough (9) with arrows showing the flow of molten glass (10) through the forming frough (9) to the side weirs (115).
  • Figure 12B shows a section through the center of the forming trough (9) which shows the different zones for the control of molten glass (10) as it flows through the forming apparatus.
  • Zone (121) is the flow from the inlet end of the trough to the far end
  • zone (122) is the flow over the weirs
  • zone (123) is the flow down the outside of the forming trough
  • zone (124) is the molten glass (11) being pulled off the root (116) and cooling into a solid sheet (12).
  • Zone (122) is important to return the glass to a uniform temperature distribution, substantially linear in the longitudinal direction, in order that the drawing process at the root (116) is consistent.
  • Differential cooling in zone (124) is the object of U.S. Patent No. 3,682,609 and is effective in making small thickness distribution changes. Cooling at given longitudinal location affects the thickness at that location in one direction and conversely to the glass on each side of the location. The effect is longitudinal redistribution of the glass over a distance on the order of centimeters.
  • FIGS 13 A and 13B show an embodiment of this invention whereby the top and sides of the muffle (132) are shaped more closely to the outside surface of the molten glass (10) that is flowing in and on the forming trough (9).
  • the muffle (132) is heated by heating elements in heating chamber (131).
  • the primary heat transfer medium in the muffle chamber (113) is radiation.
  • the heating elements in the heating chamber (131) have adequate power to balance the energy flux to the fomiing trough (9) and thus create suitable temperature conditions.
  • the two upper shaped support blocks (204) and (205) are attached to the inlet end of the weirs and are angled such that they exert an additional force on the weirs to counteract the affect of the hydrostatic forces which tend to spread the weirs apart.
  • the blocks (204) and (205) are shown with an inward angle in the figures, they also could be angled outward without deviating from the spirit of the invention.
  • the adjusting nut (524) is set such that the inlet end force (536) and the far end force (526) are substantially equal and opposite.
  • the trough (9) starts to deform via thermal creep under the influence of gravity and the applied horizontal compression forces.
  • the distance between surfaces (527) and (537) becomes less.
  • the force (538) at surface (539) between the inlet pipe (8) and the inlet end stracture (523) becomes greater as it absorbs a portion of the horizontal force from the force (526) applied at the far end of the frough.
  • force (536) at surface (537) decreases.
  • the first embodiment which may be used with a prior art apparatus, periodically adjusts the inlet end adjustment screw (524) to compensate for the shortening of the distance between surfaces (527) and (537).
  • the horizontal displacement of surface (537) may be measured and a corresponding adjustment of the screw (524) is made. Ideally the horizontal displacement of surface (537) will be halved and there will be a corresponding negative horizontal displacement of surface (527).
  • the torque on the adjustment screw (524) may also be monitored, however, the friction at surface (521) will degrade the accuracy of torque as a indicator of the force (536) actually applied to the trough (9).
  • This embodiment of the invention is counter intuitive as adjusting the adjustment screw (524) in a direction to lessen the integrity of the glass seal between the inlet pipe (8) and the trough (9) will make operating personnel nervous.
  • the far end compression force (526) is generated by the far end force motor (528).
  • the far end compression force (526) must be slightly greater than the inlet end compression forces (536) to compensate for the inlet pipe compression force (538).
  • the trough bottom compression forces (526) and (536) are applied friction free and can be maintained at the same and/or any preprogrammed level throughout a production campaign. Note that the cross-sectional shape of the inlet end compression block (543) and the far end compression block (544) is the same as that of the trough where the forces are applied to the trough. This minimizes the stress concentrations where the forces are applied.
  • There are keys (545) between the compression blocks and the frough to insure correct alignment of the compression blocks to the trough.
  • the compression block (554) is keyed to the trough at points (557) to insure correct alignment of the compression blocks to the trough.
  • a boss (559) is preferably formed into the inlet end of the trough to better distribute the inlet end compression force (556) into the trough.
  • the boss (559) is not in the glass contact area of the trough and therefore has no adverse effect on the glass flow.
  • the inlet end compression block (553) is reshaped to have the same cross-section shape as the boss (559) where the two contact each other.
  • Figures 57A through 57D show an embodiment of a sheet glass fomiing apparatus (570) whereby the inlet end adjusting screw (524) is retained and a force motor (578) is added to the inlet pipe at surface (539) to generate a constant sealing force (538) for the glass seal between the inlet pipe (8) and the frough (10).
  • Figures 23 A through 23 G show the width of the frough (211) and the angle of the inverted slope (210) being the same in the center of the trough ( Figures 21D through 21F and Figures 22D through 22F), whereas, the width of the trough (231) and the angle of the inverted slope (230) at each end are reduced.
  • This reduced width (231) and inverted slope (230) have a counterbalancing effect on the surface tension and body force stresses over the effect of Figures 22 A through 22G and thus further reduces the narrowing of the sheet (233).
  • U.S. Patent No. 3,338,696 considers only the glass flow in the forming trough and assumes that the drawn glass from the bottom of the forming trough will be of uniform thickness and flatness because of the uniform thickness of the flow of glass to the critical point of solidification.
  • glass must be preferentially cooled across its width to create forming stresses during solidification that create a flat sheet.
  • the present invention alters the forming stresses and cooling distribution such that the formed sheet is inherently flat.
  • This invention involves adjusting the internal pressure in each of the major components of the forming apparatus such that the pressure difference across any leakage path to the forming zone is essentially zero. Therefore, if an opening either exists or develops, no air leakage will occur as there is no differential pressure to force airflow.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)
  • Glass Melting And Manufacturing (AREA)

Abstract

La présente invention permet de modifier le chemin d'écoulement à l'entrée d'un appareil de formation de verre à vitre afin d'améliorer la qualité. La partie inférieure du tuyau de descente est de préférence profilée de façon à modifier le caractère de l'écoulement tourbillonnaire dans la zone de débit de repos entre les tuyaux. Dans un autre mode de réalisation, un guide bourrelets assure des contraintes hydrauliques qui sont opposées à la contrainte de tension superficielle et réduit ainsi l'influence de la tension superficielle sur la formation de bourrelets épais sur les arêtes de la vitre. La présente invention permet également de mesurer la température du verre par immersion de thermocouples dans le verre, à des emplacements où n'importe quels défauts entraînés par l'immersion sont dans le verre qui forme des arêtes inutilisables du volume. Dans un autre mode de réalisation, la structure de support de la goulotte est modifiée afin de réduire sensiblement le vieillissement de la goulotte dû à au fluage thermique.
PCT/US2004/002999 2003-02-04 2004-02-04 Appareil de formation de verre a vitre WO2004069757A2 (fr)

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
US44472803P 2003-02-04 2003-02-04
US60/444,728 2003-02-04
US44967103P 2003-02-24 2003-02-24
US60/449,671 2003-02-24
US50530203P 2003-09-23 2003-09-23
US60/505,302 2003-09-23
US53495004P 2004-01-08 2004-01-08
US60/534,950 2004-01-08

Publications (2)

Publication Number Publication Date
WO2004069757A2 true WO2004069757A2 (fr) 2004-08-19
WO2004069757A3 WO2004069757A3 (fr) 2004-11-04

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KR (1) KR101082712B1 (fr)
WO (1) WO2004069757A2 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1994944B (zh) * 2006-12-11 2010-08-11 河南安彩高科股份有限公司 一种成形砖
WO2014179291A1 (fr) * 2013-04-30 2014-11-06 Corning Incorporated Appareil et procédé destinés à la commande du flux de verre en fusion le long d'un déversoir d'isotube
JP2015199665A (ja) * 2012-09-28 2015-11-12 ＡｖａｎＳｔｒａｔｅ株式会社 ガラス基板の製造方法及びガラス基板製造装置
US20210300807A1 (en) * 2018-08-10 2021-09-30 Corning Incorporated Apparatus and methods for fabricating glass ribbon
WO2022225742A1 (fr) * 2021-04-21 2022-10-27 Corning Incorporated Appareil de fabrication de verre avec caractéristiques d'atténuation de fuite
US11702355B2 (en) 2017-11-22 2023-07-18 Corning Incorporated Apparatuses including edge directors for forming glass ribbons

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100724992B1 (ko) * 2006-02-13 2007-06-04 삼성전자주식회사 이종 통신 시스템 시스템에서의 핸드오버 방법 및 장치

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3338696A (en) * 1964-05-06 1967-08-29 Corning Glass Works Sheet forming apparatus
US3437470A (en) * 1966-06-17 1969-04-08 Corning Glass Works Constant force internal support for glass overflow wedge
US3723082A (en) * 1971-01-06 1973-03-27 Corning Glass Works Sheet glass thickness control

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3338696A (en) * 1964-05-06 1967-08-29 Corning Glass Works Sheet forming apparatus
US3437470A (en) * 1966-06-17 1969-04-08 Corning Glass Works Constant force internal support for glass overflow wedge
US3723082A (en) * 1971-01-06 1973-03-27 Corning Glass Works Sheet glass thickness control

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1994944B (zh) * 2006-12-11 2010-08-11 河南安彩高科股份有限公司 一种成形砖
JP2015199665A (ja) * 2012-09-28 2015-11-12 ＡｖａｎＳｔｒａｔｅ株式会社 ガラス基板の製造方法及びガラス基板製造装置
WO2014179291A1 (fr) * 2013-04-30 2014-11-06 Corning Incorporated Appareil et procédé destinés à la commande du flux de verre en fusion le long d'un déversoir d'isotube
CN105164070A (zh) * 2013-04-30 2015-12-16 康宁股份有限公司 用于沿着溢流槽堰的熔融玻璃流控制的设备和方法
US10421682B2 (en) 2013-04-30 2019-09-24 Corning Incorporated Apparatus and method for molten glass flow control along an isopipe weir
US11639305B2 (en) 2013-04-30 2023-05-02 Corning Incorporated Apparatus and method for molten glass flow control along an isopipe weir
US11702355B2 (en) 2017-11-22 2023-07-18 Corning Incorporated Apparatuses including edge directors for forming glass ribbons
US20210300807A1 (en) * 2018-08-10 2021-09-30 Corning Incorporated Apparatus and methods for fabricating glass ribbon
WO2022225742A1 (fr) * 2021-04-21 2022-10-27 Corning Incorporated Appareil de fabrication de verre avec caractéristiques d'atténuation de fuite

Also Published As

Publication number Publication date
KR20050112081A (ko) 2005-11-29
WO2004069757A3 (fr) 2004-11-04
KR101082712B1 (ko) 2011-11-15

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