TWI856032B - Glass forming apparatus and methods - Google Patents

Abstract

A glass forming apparatus includes a cooling tube including a first tube including a closed first sidewall and a closed first end, and a second tube including a closed second end and a second sidewall defining an orifice. The second tube is positioned within the first tube. The cooling tube includes a channel between the closed first sidewall and the second sidewall. The cooling tube receives a cooling fluid within one of the second tube or the channel and passes the cooling fluid through the orifice. Additionally, methods of forming a ribbon with a glass forming apparatus are disclosed.

Description

Glass forming apparatus and method

This application claims the benefit of priority to U.S. Provisional Patent Application No. 62/753,272 filed on October 31, 2018, the entire contents of which are hereby attached and incorporated herein by reference as if fully set forth below.

The present disclosure relates generally to methods for forming a glass ribbon, and more particularly to methods for forming a glass ribbon using a glass forming apparatus including a cooling tube.

It is known to cool a glass ribbon with a cooling tube located below the forming wedge. The cooling tube is maintained at a low temperature, which can cool the glass ribbon as it moves past the cooling tube. However, maintaining the cooling tube at too low a temperature can result in undesirable convection chambers and inconsistent cooling of the glass ribbon. As a result, thickness variations of the glass ribbon can occur in the transverse draw and down draw directions.

The following presents a simplified summary of the disclosure in order to provide a basic understanding of some embodiments described in the detailed description.

According to some embodiments, a glass forming apparatus may include a cooling tube including a first tube including a closed first sidewall and a closed first end; and a second tube including a closed second end and a second sidewall defining an orifice. The second tube may be positioned within the first tube. The cooling tube may include a channel between the closed first sidewall and the second sidewall. The cooling tube may receive a cooling fluid in one of the second tube or the channel and pass the cooling fluid through the orifice.

In some embodiments, one or more of the first tube or the second tube can include a cylindrical shape.

In some embodiments, the second tube is coaxial with the first tube.

In some embodiments, the orifice includes a plurality of orifices.

In some embodiments, the orifice can extend along 50% or more of the length of the second tube.

In some embodiments, the orifice may extend along 50% or less of the length of the second tube.

In some embodiments, the cooling fluid may include a gas.

In some embodiments, a glass forming apparatus may include an upper housing portion, a travel path defined by the glass forming apparatus may extend within the upper housing portion. The upper housing portion may include a cooling tube. A first free path may extend between the cooling tube and the travel path in a first free path direction, and the first free path direction may be orthogonal to the travel path.

In some embodiments, the cooling tube may include a first tube, the first tube may include a closed first sidewall and a closed first end. The cooling tube may include a second tube, the second tube may include a closed second end and a second sidewall defining an orifice. The second tube may be positioned within the first tube. The cooling tube may include a channel between the closed first sidewall and the second sidewall. The cooling tube may be configured to receive a cooling fluid in one of the second tube or the channel and pass the cooling fluid through the orifice.

In some embodiments, the travel path may extend into a lower housing portion positioned below the upper housing portion. The lower housing portion further includes a lower cooling tube and a second free path extending between the lower cooling tube and the travel path in a second free path direction.

In some embodiments, the first free path direction can be substantially parallel to the second free path direction.

In some embodiments, the temperature difference between the strip at the location where the strip passes through the cooling tube and the outer surface of the cooling tube can be less than about 649°C.

In some embodiments, a method of forming a ribbon using the glass forming apparatus may include the steps of moving the ribbon in a travel direction along a travel path through the cooling tube. The method may include the steps of receiving the cooling fluid in the second tube. The method may include the steps of directing the cooling fluid through the orifice and through the channel to cool the closed first sidewall.

In some embodiments, the step of directing the cooling fluid through the orifice may include the step of maintaining the temperature of the outer surface of the cooling tube at from about 400°C to about 600°C.

In some embodiments, a method may include the step of removing the cooling fluid from the channel along a first direction, which may be opposite to a second direction along which the cooling fluid may flow within the second tube.

In some embodiments, the step of removing the cooling fluid may include the step of directing the cooling fluid along a removal path that is substantially parallel to an axis along which the second tube extends.

In some embodiments, a method of forming a ribbon using the glass forming apparatus may include the step of moving the ribbon through a cooling tube along a travel path in a travel direction. The method may include the step of flowing a cooling fluid through the cooling tube such that a temperature difference between the ribbon and an outer surface of the cooling tube at a location where the ribbon passes through the cooling tube is less than about 649°C.

In some embodiments, the method may include the step of preventing the cooling fluid from passing through the outer surface of the cooling tube.

In some embodiments, the step of flowing the cooling fluid through the cooling tube causes the temperature difference between the strip at the location where the strip passes through the cooling tube and the outer surface of the cooling tube to be less than about 553°C.

In some embodiments, the step of flowing the cooling fluid through the cooling tube causes the temperature difference between the strip at the location where the strip passes through the cooling tube and the outer surface of the cooling tube to be less than about 459°C.

Additional features and advantages of the embodiments disclosed herein will be described in the detailed description that follows, and those skilled in the art will understand a portion of these features and advantages from this description, or recognize these features and advantages by practicing the embodiments as described herein, which include the detailed description that follows, the claims, and the accompanying drawings. It is to be understood that the foregoing general description and the following detailed description present embodiments that are intended to provide an overview or framework for understanding the nature and characteristics of the embodiments disclosed herein. The accompanying drawings are included to provide further understanding, and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate various embodiments of the disclosure and, together with the specification, explain the principles and operation of the disclosure.

Embodiments will now be described more fully below with reference to the accompanying drawings, in which example embodiments are shown. The same reference numerals are used throughout the drawings to refer to the same or similar components wherever possible. However, this disclosure may be implemented in many different forms, and this disclosure should not be construed as limited to the embodiments described herein.

The present disclosure relates to glass forming apparatus and methods for forming glass. Methods and apparatus for forming glass will now be described by way of example embodiments for forming a glass ribbon from a quantity of molten material. As schematically illustrated in FIG . 1 , in some embodiments, an exemplary glass manufacturing apparatus 100 may include a glass melting and delivery apparatus 102 and a forming apparatus 101 , the forming apparatus including a forming vessel 140 , the forming vessel being configured to produce a ribbon 103 from a quantity of molten material 121 . In some embodiments, the ribbon 103 may include a center portion 152 , the center portion being positioned between opposing edge portions (e.g., edge beads) formed along a first outer edge 153 and a second outer edge 155 of the ribbon 103 , wherein the edge beads may have a thickness greater than a thickness of the center portion. Additionally, in some embodiments, the separated glass ribbon 104 can be separated from the ribbon 103 along the separation path 151 by a glass separator 149 (e.g., a scribe, a scribing wheel, a diamond tip, a laser, etc.). In some embodiments, before or after the separated glass ribbon 104 is separated from the ribbon 103 , edge beads formed along the first outer edge 152 and the second outer edge 155 can be removed to provide the center portion 152 as a high-quality separated glass ribbon 104 having a uniform thickness.

In some embodiments, the glass melting and delivery apparatus 102 may include a melting vessel 105 oriented to receive a batch material 107 from a storage rack 109. The batch material 107 may be introduced by a batch delivery device 111 , which is powered by a motor 113. In some embodiments, an optional controller 115 may be operated to activate the motor 113 to introduce a desired amount of the batch material 107 into the melting vessel 105 , as indicated by arrow 117. The melting vessel 105 may heat the batch material 107 to provide a molten material 121. In some embodiments, a melt probe 119 may be used to measure the level of the molten material 121 within the vertical tube 123 and transmit the measured information to the controller 115 via a communication line 125 .

Additionally, in some embodiments, the glass melting and delivery apparatus 102 may include a first conditioning station including a fining vessel 127 located downstream of the melting vessel 105 and coupled to the melting vessel 105 via a first connecting conduit 129. In some embodiments, the molten material 121 may be gravity fed from the melting vessel 105 to the fining vessel 127 via the first connecting conduit 129. For example, in some embodiments, gravity may drive the molten material 121 from the melting vessel 105 through the internal path of the first connecting conduit 129 to the fining vessel 127. Additionally, in some embodiments, bubbles may be removed from the molten material 121 within the fining vessel 127 by various techniques.

In some embodiments, the glass melting and delivery apparatus 102 may further include a second conditioning station including a mixing chamber 131 that may be located downstream of the fining vessel 127. The mixing chamber 131 may be employed to provide a uniform composition of the molten material 121 , thereby reducing or eliminating inhomogeneities that may otherwise exist in the molten material 121 exiting the fining vessel 127. As shown, the fining vessel 127 may be coupled to the mixing chamber 131 via a second connecting conduit 135. In some embodiments, the molten material 121 may be gravity fed from the fining vessel 127 to the mixing chamber 131 via the second connecting conduit 135. For example, in some embodiments, gravity may drive the molten material 121 from the fining vessel 127 through the internal path of the second connecting conduit 135 to the mixing chamber 131 .

Additionally, in some embodiments, the glass melting and delivery apparatus 102 can include a third conditioning station including a delivery vessel 133 that can be located downstream of the mixing chamber 131. In some embodiments, the delivery vessel 133 can condition the molten material 121 to be fed into the inlet conduit 141. For example, the delivery vessel 133 can act as an accumulator and/or a flow controller to regulate and provide a consistent flow of the molten material 121 to the inlet conduit 141. As shown, the mixing chamber 131 can be coupled to the delivery vessel 133 via a third connecting conduit 137. In some embodiments, the molten material 121 can be gravity fed from the mixing chamber 131 to the delivery vessel 133 via the third connecting conduit 137 . For example, in some embodiments, gravity can drive the molten material 121 from the mixing chamber 131 through the internal path of the third connecting conduit 137 to the delivery container 133. As further shown, in some embodiments, the delivery tube 139 can be positioned to deliver the molten material 121 to the forming device 101 (e.g., the inlet conduit 141 of the forming container 140 ).

The forming apparatus 101 may include various embodiments of a forming vessel in accordance with features of the present disclosure, including a forming vessel having a wedge for melt-drawing a glass strip, a forming vessel having narrow grooves for groove-drawing a glass strip, or a forming vessel equipped with a rolling roller to roll a glass strip from the forming vessel. By way of illustration, a forming vessel 140 shown and disclosed below may be provided to melt-draw a molten material 121 off a bottom edge (defined as a root 145 ) of a forming wedge 209 to produce a strip of molten material 121 that may be drawn into a strip 103. For example, in some embodiments, the molten material 121 may be delivered from an inlet conduit 141 to the forming vessel 140. The molten material 121 may then be formed into a strip 103 based in part on the structure of the forming vessel 140 . For example, as shown, the molten material 121 can be pulled away from a bottom edge (e.g., root 145 ) of the forming vessel 140 along a draw path extending in a draw direction 154 of the glassmaking apparatus 100. In some embodiments, edge guides 163 , 164 can direct the molten material 121 away from the forming vessel 140 and partially define a width " W " of the strip 103. In some embodiments, the width " W " of the strip 103 extends between a first outer edge 153 of the strip 103 and a second outer edge 155 of the strip 103 .

In some embodiments, the width " W " of the strip 103 (which extends between the first outer edge 153 of the strip 103 and the second outer edge 155 of the strip 103 ) can be greater than or equal to about 20 millimeters (mm), such as greater than or equal to about 50 mm, such as greater than or equal to about 100 mm, such as greater than or equal to about 500 mm, such as greater than or equal to about 1000 mm, such as greater than or equal to about 2000 mm, such as greater than or equal to about 3000 mm, such as greater than or equal to about 4000 mm, although other widths less than or greater than the above widths may also be provided in other embodiments. For example, in some embodiments, the width " W " of the strip 103 can be from about 20 mm to about 4000 mm, such as from about 50 mm to about 4000 mm, such as from about 100 mm to about 4000 mm, such as from about 500 mm to about 4000 mm, such as from about 1000 mm to about 4000 mm, such as from about 2000 mm to about 4000 mm, such as from about 3000 mm to about 4000 mm, such as from about 20 mm to about 3000 mm, such as from about 50 mm to about 3000 mm, such as from about 100 mm to about 3000 mm, such as from about 500 mm to about 3000 mm, such as from about 1000 mm to about 3000 mm, such as from about 2000 mm to about 3000 mm, such as from about 2000 mm to about 2500 mm, and all ranges and sub-ranges therebetween.

FIG. 2 shows a cross-sectional perspective view of a forming apparatus 101 (e.g., a forming vessel 140 ) along line 2-2 of FIG . 1. In some embodiments, the forming vessel 140 can include a launder 201 oriented to receive molten material 121 from an inlet conduit 141. For purposes of illustration, the cross-hatching of the molten material 121 is removed from FIG . 2 for clarity. The forming vessel 140 can further include a forming wedge 209 including a pair of downwardly inclined converging surface portions 207 , 208 extending between opposite ends 210 , 211 (see FIG . 1 ) of the forming wedge 209. The pair of downwardly inclined converging surface portions 207 , 208 of the forming wedge 209 can converge along the draw direction 154 to intersect along the root 145 of the forming vessel 140 . A drawing plane 213 of the glassmaking apparatus 100 can extend through the root 145 along the drawing direction 154. In some embodiments, the strip 103 can be drawn in the drawing direction 154 along the drawing plane 213. As shown, the drawing plane 213 can bisect the root 145 to form a wedge 209 , however, in some embodiments, the drawing plane 213 can extend in other orientations relative to the root 145 .

Furthermore, in some embodiments, the molten material 121 can flow in the direction 156 into and along the flow channel 201 forming the container 140. The molten material 121 can then overflow the flow channel 201 by simultaneously flowing over the corresponding weirs 203 , 204 and flowing downward over the outer surfaces 205 , 206 of the corresponding weirs 203 , 204. The corresponding stream of the molten material 121 can then flow along the downwardly inclined converging surface portions 207 , 208 of the forming wedge 209 and be drawn away from the root 145 forming the container 140 , where the stream converges and merges into the strip 103. The strip 103 of molten material can then be drawn away from the root 145 on the draw plane 213 along the draw direction 154 . In some embodiments, the strip 103 includes one or more material states based on the vertical position of the strip 103. For example, at one position, the strip 103 may include a viscous molten material 121 , and at another position, the strip 103 may include an amorphous solid in a glass state (e.g., a glass strip).

The strip 103 includes a first major face 215 and a second major face 216 that face in opposite directions and define a thickness " T " (e.g., average thickness) of the strip 103. In some embodiments, the thickness " T " of the strip 103 can be less than or equal to about 2 millimeters (mm), less than or equal to about 1 mm, less than or equal to about 0.5 mm, such as less than or equal to about 300 micrometers (µm), less than or equal to about 200 µm, or less than or equal to about 100 µm, although other thicknesses may be provided in other embodiments. For example, in some embodiments, the thickness " T " of the strip 103 can be from about 50 µm to about 750 µm, from about 100 µm to about 700 µm, from about 200 µm to about 600 µm, from about 300 µm to about 500 µm, from about 50 µm to about 500 µm, from about 50 µm to about 700 µm, from about 50 µm to about 600 µm, from about 50 µm to about 500 µm, from about 50 µm to about 400 µm, from about 50 µm to about 300 µm, from about 50 µm to about 200 µm, from about 50 µm to about 100 µm, including all thickness ranges and thickness sub-ranges therebetween. Additionally, the strip 103 may include a variety of compositions including, but not limited to, sodium calcium glass, borosilicate glass, aluminum borosilicate glass, alkali-containing glass, or alkali-free glass.

In some embodiments, a glass separator 149 (see FIG. 1 ) can then separate the glass pieces 104 from the strip 103 along a separation path 151 as the strip 103 is formed from the forming container 140. As depicted, in some embodiments, the separation path 151 can extend along a width “ W ” of the strip 103 between a first outer edge 153 and a second outer edge 155. Additionally, in some embodiments, the separation path 151 can extend perpendicular to a draw direction 154 of the strip 103. And, in some embodiments, the draw direction 154 can define a direction along which the strip 103 can be pulled from the forming container 140 .

In some embodiments, a plurality of separated glass ribbons 104 may be stacked to form a stack of separated glass ribbons 104. In some embodiments, an interlayer material may be disposed between adjacent pairs of separated glass ribbons 104 to help prevent contact and thereby preserve the original surfaces of the pair of separated glass ribbons 104 .

In another embodiment, although not shown, the strip 103 from the glass manufacturing device can be wound onto a storage drum. Once the wound strip of the desired length is stored on the storage drum, the strip 103 can be separated by the glass separator 149 so that the separated glass strips are stored on the storage drum. In another embodiment, the separated glass strip can be separated into another separated glass strip. For example, the separated glass strip 104 (e.g., from a stack of glass strips) can be further separated into another separated glass strip. In other embodiments, the separated glass ribbon stored on the storage drum may be unrolled and further separated into another separated glass ribbon.

The separated glass strips may then be processed into a desired application (e.g., a display application). For example, the separated glass strips may be used in a wide range of display applications, including liquid crystal displays (LCDs), electrophoretic displays (EPDs), organic light emitting diode displays (OLEDs), plasma display panels (PDPs), and other electronic displays.

3 , an example of a glass cooling apparatus 301 of the glass forming apparatus 101 along line 3-3 of FIG . 2 is illustrated. In some embodiments, the glass cooling apparatus 301 can include one or more cooling doors 303. The cooling doors 303 can be positioned near the root 145 of the forming wedge 209 , with one cooling door 303 positioned to face the first major face 215 of the strip 103 and another cooling door 303 positioned to face the second major face 216 of the strip 103. In some embodiments, a travel path 305 defined by the glass forming apparatus 101 (e.g., a travel path along which the strip 103 travels) can extend between the cooling doors 303. The cooling doors 303 can include a cooling tube 307 and a hot plate 309 . The cooling tube 307 can receive the cooling fluid and direct the cooling fluid toward the hot plate 309. In some embodiments, the cooling fluid impinging on the hot plate 309 can cool the hot plate 309 to a desired temperature. Such cooling of the hot plate 309 can thus cool the strip 103 below the forming wedge 209 .

The glass cooling apparatus 301 can include a housing 311 that can be positioned downstream of the forming wedge 209 and below the cooling doors 303. In some embodiments, the housing 311 can include an upper housing portion 313 and a lower housing portion 315. The upper housing portion 313 can be positioned below and directly downstream of the cooling doors 303. The upper housing portion 313 can define a hollow upper housing chamber 317 through which the strip 103 can move. For example, the travel path 305 defined by the glass forming apparatus 101 can extend within the upper housing portion 313 (e.g., within the upper housing chamber 317 ). The strip 103 can move through the upper housing portion 313 along the travel path 305 in the travel direction 319 .

The upper shell portion 313 can include one or more upper shell walls 321. In some embodiments, the upper shell walls 321 can be positioned on opposite sides of the travel path 305 , with one of the upper shell walls 321 positioned to face the first major face 215 of the strip 103 (e.g., as the strip 103 moves along the travel path 305 ) and another upper shell wall 321 positioned to face the second major face 216 of the strip 103. The upper shell walls 321 can be spaced apart from each other to define an upper shell chamber 317 therebetween. In some embodiments, the upper shell walls 321 can include a refractory insulating material to reduce heat conduction through the upper shell walls 321 . The refractory insulating material of the upper shell wall 321 may include, for example, a non-metallic material including chemical and physical properties of a structure that makes the upper shell wall 321 suitable for exposure to an environment equal to or greater than about 500°C, equal to or greater than about 700°C, or equal to or greater than about 800°C.

The upper housing portion 313 may include one or more cooling tubes 325. The one or more cooling tubes 325 may be positioned within the upper housing chamber 317 between the travel path 305 and the upper housing wall 321. For example, the upper housing portion 313 includes the cooling tubes 325 within which the travel path 305 defined by the glass forming apparatus 101 extends. In some embodiments, the upper housing portion 313 may include one or more cooling tubes 325 positioned on one side of the travel path 305 and one or more cooling tubes 325 positioned on an opposite side of the travel path 305 . For example, one or more cooling tubes 325 may be positioned to face the first major face 215 of the strip 103 (e.g., as the strip 103 moves along the travel path 305 ), and one or more cooling tubes 325 may be positioned to face the second major face 216 of the strip 103. The one or more cooling tubes 325 facing the first major face 215 may be spaced apart from the one or more cooling tubes 325 facing the second major face 216 to define a gap therebetween, wherein the travel path 305 extends through the gap and between the one or more cooling tubes 325 facing the first major face 215 and the one or more cooling tubes 325 facing the second major face 216. In this manner, the strip 103 may travel between the one or more cooling tubes 325 as it moves along the travel path 305 . In some embodiments, the one or more cooling tubes 325 may include three cooling tubes positioned on one side of the travel path 305 and three cooling tubes positioned on an opposite side of the travel path 305. However, such a configuration is not intended to be limiting, and in some embodiments, the one or more cooling tubes 325 may include more than three cooling tubes 325 positioned on each side of the travel path 305 .

In some embodiments, the one or more cooling tubes 325 may be arranged along a vertical axis (e.g., one cooling tube positioned above another cooling tube), wherein the vertical axis extends substantially parallel to the travel path 305 or does not extend parallel to the travel path 305. In some embodiments, the one or more cooling tubes 325 may be arranged along a non-vertical axis, such as by staggering (e.g., some cooling tubes 325 are positioned closer to the travel path 305 than other cooling tubes 325 ). In some embodiments, the one or more cooling tubes 325 may be spaced apart from adjacent cooling tubes 325 along a vertical direction, such that the cooling tubes 325 may not contact each other. In some embodiments, the distance separating adjacent cooling tubes 325 along the vertical direction may be constant. For example, the distance separating adjacent cooling tubes 325 (e.g., the distance separating one cooling tube from the nearest cooling tube) may be the same as another distance separating another pair of adjacent cooling tubes 325 along the vertical direction. In some embodiments, the distance separating adjacent cooling tubes 325 along the vertical direction may not be constant. For example, the distance separating adjacent cooling tubes 325 (e.g., the distance separating one cooling tube from the nearest cooling tube) can be different from another distance separating another pair of adjacent cooling tubes 325 in the vertical direction.

In some embodiments, the one or more cooling tubes 325 can be positioned to extend in a width direction relative to the strip 103 moving along the travel path 305. For example, the one or more cooling tubes 325 can extend along a tube axis 326 (e.g., where the tube axis 326 extends into and out of the page in FIG . 3 ), which can be orthogonal to the direction of travel 319 and orthogonal to the travel path 305. In some embodiments, the one or more cooling tubes 325 can be attached within the upper housing portion 313 , such as by attaching to the upper housing wall 321 , so that the one or more cooling tubes 325 can be fixed relative to the travel path 305 . In some embodiments, the one or more cooling tubes 325 can be coupled to one or more of a valve, a gasket, or a fluid supply so that cooling fluid can be delivered to and exhausted from the cooling tubes 325 .

In some embodiments, the free path may extend between the one or more cooling tubes 325 and the travel path 305 in a free path direction. For example, the one or more cooling tubes 325 may include cooling tube 327. A first free path 329 may extend between cooling tube 327 and travel path 305 in a first free path direction 331 , which may be orthogonal to travel path 305. In some embodiments, the free path may be unobstructed without any intervening structure between cooling tubes 325 , 345 and travel path 305. For example, the free path may include a first free path 329 and a second free path 349 . The first free path 329 is unobstructed and does not have any intervening structure between the cooling tube 327 and the travel path 305. As such, the cooling tube 327 and the strip 103 may define an unoccupied space therebetween. It will be appreciated that the first free path 329 is not limited to extending between the cooling tube 327 and the travel path 305. Rather, in some embodiments, the free path may extend between other cooling tubes 325 and the travel path 305 in a free path direction that is orthogonal to the travel path 305 and parallel to the first free path 329 .

In some embodiments, the glass cooler 301 can include one or more spacer members 335 separating the upper housing portion 313 and the lower housing portion 315. For example, the spacer members 335 can extend from the upper housing wall 321 toward the travel path 305. The spacer members 335 can be spaced apart from each other to define a gap through which the travel path 305 extends. The spacer members 335 can increase or decrease the direct "view" of the molten glass near the root 145 to the cooler area of the glass cooler 301 (e.g., within the lower housing portion 315 ). For example, in some embodiments, the separator member 335 may include a baffle extending into the upper shell portion 313 or the lower shell portion 315 and may be able to rotate about a hinge end to thereby increase or decrease the line of sight between the root 145 and the structure within the lower shell portion 315. In other words, the line of sight between the root 145 and the structural members of the lower shell portion 315 may be varied. Although FIG. 3 illustrates the separator member 335 as being positioned in the upper shell portion 313 , the separator member 335 may also be positioned in other locations, such as within the lower shell portion 315 or between the upper shell portion 313 and the lower shell portion 315 .

The lower housing portion 315 can be positioned directly below the upper housing portion 313. As such, the lower housing portion 315 can be positioned downstream of the upper housing portion 313 along the travel path 305 relative to the direction of travel 319 of the strip 103. The lower housing portion 315 can define a hollow lower housing chamber 341 through which the strip 103 can move. For example, the travel path 305 of the glass forming apparatus 101 can extend within the lower housing portion 315 (e.g., within the lower housing chamber 341 ), which is positioned below the upper housing portion 313. The strip 103 can move through the lower housing portion 315 along the travel path 305 in the direction of travel 319 . In some embodiments, the strip 103 moves along the travel path 305 in the travel direction and passes through the upper shell portion 313 before passing through the lower shell portion 315 .

The lower shell portion 315 can include one or more lower shell walls 343. In some embodiments, the lower shell walls 343 can be positioned on opposite sides of the travel path 305 , with one of the lower shell walls 343 positioned to face the first major face 215 of the strip 103 (e.g., as the strip 103 moves along the travel path 305 ) and another lower shell wall 343 positioned to face the second major face 216 of the strip 103. The lower shell walls 343 can be spaced apart from each other to define a lower shell chamber 341 therebetween. In some embodiments, the lower shell walls 343 can include a refractory insulating material to reduce heat conduction through the lower shell walls 343 . The refractory insulation material of the lower shell wall 343 may include, for example, a non-metallic material including chemical and physical properties of a structure that makes the lower shell wall 343 suitable for exposure to an environment equal to or greater than about 500° C., equal to or greater than about 700° C., or equal to or greater than about 800° C. In some embodiments, the refractory insulation material of the lower shell wall 343 may be the same as the refractory insulation material of the upper shell wall 321 .

The lower housing portion 315 may include one or more lower cooling tubes 345. The one or more lower cooling tubes 345 may be positioned within the lower housing chamber 341 between the travel path 305 and the lower housing wall 343. In some embodiments, the lower housing portion 315 may include one or more lower cooling tubes 345 positioned on one side of the travel path 305 and one or more lower cooling tubes 345 positioned on an opposite side of the travel path 305. For example, the one or more lower cooling tubes 345 may be positioned to face the first major face 215 of the strip 103 (e.g., as the strip 103 moves along the travel path 305 ), and the one or more lower cooling tubes 345 may be positioned to face the second major face 216 of the strip 103 . The one or more lower cooling tubes 345 facing the first major face 215 can be spaced apart from the one or more lower cooling tubes 345 facing the second major face 216 to define a gap therebetween, wherein the travel path 305 extends through the gap and between the one or more lower cooling tubes 345 facing the first major face 215 and the one or more lower cooling tubes 345 facing the second major face 216. In this way, the strip 103 can travel between the one or more lower cooling tubes 345 as it moves along the travel path 305. In some embodiments, the one or more lower cooling tubes 345 can include four lower cooling tubes positioned on one side of the travel path 305 and four lower cooling tubes positioned on an opposite side of the travel path 305 . However, such a configuration is not intended to be limiting, and in some embodiments, one or more lower cooling tubes 345 may be positioned on one side of the travel path 305 , while one or more lower cooling tubes 345 may be positioned on an opposite side of the travel path 305 .

In some embodiments, the one or more lower cooling tubes 345 can be positioned to extend in a width direction relative to the strip 103 moving along the travel path 305. For example, the one or more lower cooling tubes 345 can extend along a lower axis 348 (e.g., where the lower axis 348 extends into and out of the page in FIG. 3 ), which can be orthogonal to the direction of travel 319 and parallel to the travel path 305. In some embodiments, the one or more lower cooling tubes 345 can be attached within the lower housing portion 315 , such as by attaching to the lower housing wall 343 , so that the one or more lower cooling tubes 345 can be fixed relative to the travel path 305 . In some embodiments, the one or more lower cooling tubes 345 can be coupled to one or more of a valve, a gasket, or a fluid supply source so that cooling fluid can be delivered to and discharged from the lower cooling tubes 345 .

In some embodiments, the free path can extend between the one or more lower cooling tubes 345 and the travel path in a free path direction. For example, the one or more lower cooling tubes 345 can include a lower cooling tube 347. A second free path 349 can extend between the lower cooling tube 347 and the travel path 305 in a second free path direction 351 , which can be orthogonal to the travel path 305. In some embodiments, the second free path 349 is unobstructed and there is no intervening structure between the lower cooling tube 347 and the travel path 305. As such, the lower cooling tube 347 and the strip 103 can define an unoccupied space therebetween. In some embodiments, the first free path direction 331 can be substantially parallel to the second free path direction 351. It will be understood that the free path is not limited to extending between the lower cooling tube 347 and the travel path 305. Rather, in some embodiments, the free path can extend between other lower cooling tubes 345 and the travel path 305 in a free path direction that is orthogonal to the travel path 305 and parallel to the second free path 349 .

In some embodiments, a method of forming a strip 103 with a glass forming apparatus 101 can include moving the strip 103 along a travel path 305 in a travel direction 319 through a cooling tube 327 of the one or more cooling tubes 325. For example, the travel path 305 can be oriented substantially vertically such that the travel direction 319 of the strip 103 can be in a downward direction. The strip 103 can move along the travel path 305 through an upper housing portion 313 and a lower housing portion 315. In some embodiments, the travel path 305 is flat and extends through the upper housing portion 313 and the lower housing portion 315 . In some embodiments, the strip 103 may move past the cooling tube 327 and the one or more cooling tubes 325 as the strip 103 moves through the upper housing portion 313. The strip 103 may move past the lower cooling tube 347 and the one or more lower cooling tubes 345 as the strip 103 moves through the lower housing portion 315. In some embodiments, the step of moving the strip 103 may include the step of cooling the strip 103 as the strip 103 moves through the cooling tube 327. For example, the cooling tube 327 may be maintained at a lower temperature relative to the temperature of the strip 103 as the strip 103 passes through the cooling tube 327 . As such, the cooling tubes 327 can reduce the temperature of the air surrounding the travel path 305 and the strip 103. The cooling tubes 327 can thus cool the strip 103 as the strip 103 moves past the cooling tubes 327 .

4-5 , FIG4 illustrates a cross-sectional view of the cooling tube 327 along line 4-4 of FIG3 , and FIG5 illustrates a cross-sectional view of the cooling tube 327 along line 5-5 of FIG4 . An embodiment of the cooling tube 327 in the one or more cooling tubes 325 and/or the one or more lower cooling tubes 345 is illustrated. The cooling tube 327 can be positioned along the travel path 305 of the strip 103 and can reduce the temperature of the strip 103 as the strip 103 moves past the cooling tube 327 in the travel direction 319 . In some embodiments, the cooling tube 327 may include a radiant type cooling tube when not exhausted from the cooling tube 327 except through fittings that may be designed to supply cooling fluid to and/or remove cooling fluid from the cooling tube 327. For example, the cooling tube 327 may not include an orifice in an outer surface to exhaust cooling fluid from the cooling tube 327 to the upper shell chamber 317. Instead, the cooling fluid may be contained within the cooling tube 327 such that the cooling fluid may be prevented from escaping from the cooling tube 327 and into the upper shell chamber 317 and/or the lower shell chamber 341 .

In some embodiments, the cooling tube 327 may include a first tube 401 and a second tube 403 , wherein the first tube 401 and/or the second tube 403 extend along a tube axis 326. For example, the first tube 401 may extend longitudinally along the tube axis 326 between a proximal end 405 and a distal end 407. The tube axis 326 may include a central tube axis of the first tube 401 and/or the second tube 403. The first tube 401 may include a closed first sidewall 409 and a closed first end 411. The closed first sidewall 409 and the closed first end 411 may not contain openings, orifices, gaps, vents, etc., so that the cooling fluid may be prevented from leaving the first tube 401 by passing through the closed first sidewall 409 or the closed first end 411 . The closed first sidewall 409 and the closed first end 411 may define a hollow first tube interior 413. In some embodiments, the first tube 401 may include a thermally conductive material, such as one or more of stainless steel, nickel alloy, titanium alloy, molybdenum alloy, tungsten alloy, or cobalt alloy.

By configuring the first tube 401 with the closed first sidewall 409 and the closed first end 411 , several benefits can be achieved. For example, the cooling fluid flowing through the cooling tube 327 can be contained within the cooling tube 327 and prevented from leaving the first tube 401 by passing through the closed first sidewall 409 and the closed first end 411. In some embodiments, when the cooling fluid leaves the cooling tube 327 and flows within the upper shell chamber 317 , air flows may be generated within the upper shell chamber 317. These air flows may cause temperature fluctuations within the upper shell chamber 317 , wherein different areas of the upper shell chamber 317 have relatively large temperature differences. As a result of these temperature differences, thickness and viscosity variations may occur within the strip 103. Thus, when the first tube 401 is closed (e.g., by including a closed first sidewall 409 and a closed first end 411 ), these temperature variations may be reduced, and therefore thickness and viscosity variations in the strip 103 may be reduced.

The second tube 403 can be positioned within the first tube 401. For example, the second tube 403 can be received within the first tube interior 413 of the first tube 401 , wherein the second tube 403 is coaxial with the first tube 401. In some embodiments, the second tube 403 can extend longitudinally along the tube axis 326 between the proximal end 415 and the distal end 417. In some embodiments, one or more fittings can be coupled to the proximal end 405 of the first tube 401 and/or the proximal end 415 of the second tube 403. The one or more fittings can be configured to deliver cooling fluid through the proximal end 415 of the second tube 403 and receive cooling fluid from the proximal end 405 of the first tube 401 . In this way, the proximal end 405 of the first tube 401 and the proximal end 415 of the second tube 403 may define an opening, while the distal end 407 of the first tube 401 and the distal end 417 of the second tube 403 may be closed.

The second tube 403 may include a closed second end 421 and a second sidewall 419 defining an orifice. The closed second end 421 may be free of openings, orifices, gaps, vents, etc., so that the cooling fluid may be prevented from leaving the second tube 403 by passing through the closed second end 421. The second sidewall 419 and the closed second end 421 may define a hollow second tube interior 422. In some embodiments, the second tube 403 may include a thermally conductive material, such as one or more of stainless steel, a nickel alloy, a titanium alloy, a molybdenum alloy, a tungsten alloy, or a cobalt alloy. In other embodiments, the second tube 403 may include a non-thermally conductive material, such as a non-metallic material (e.g., ceramic, etc.). In some embodiments, the second sidewall 419 may be concentric with the closed first sidewall 409 . For example, one or more of the closed first side wall 409 of the first tube 401 or the second side wall 419 of the second tube 403 may include a cylindrical shape (e.g., a circular cross-sectional shape on a plane orthogonal to the tube axis 326 ), wherein the second side wall 419 is separated from the closed first side wall 409 by a certain distance along the length of the second tube 403 . The closed first side wall 409 of the first tube 401 and the second side wall 419 of the second tube 403 are not limited to including a cylindrical shape (for example, a circular cross-sectional shape on a plane orthogonal to the tube axis 326 ), and in some embodiments, one or more of the closed first side wall 409 of the first tube 401 or the second side wall 419 of the second tube 403 may include an elliptical cross-sectional shape, a quadrilateral cross-sectional shape (for example, a square, rectangle, etc.), a triangular cross-sectional shape, or other shapes.

In some embodiments, the second sidewall 419 may define one or more orifices 423. For example, the one or more orifices 423 may extend through the second sidewall 419 of the second tube 403 and may be arranged along the length of the second tube 403. Although a plurality of orifices are shown in FIG . 4 , the second sidewall 419 is not limited thereto. In some embodiments, the second sidewall 419 may include one orifice (e.g., 425 ) or the orifice may include a plurality of orifices 423. The one or more orifices 423 may define a fluid path through which the cooling fluid may exit the second tube 403. For example, the cooling fluid may exit the second tube interior 422 of the second tube 403 by passing through the one or more orifices 423 . In some embodiments, the orifice 425 can extend along about 50% or less of the length of the second tube 403 , or 40% or less of the length of the second tube 403 , or 30% or less of the length of the second tube 403 , or 20% or less of the length of the second tube 403 , or 10% or less of the length of the second tube 403. In some embodiments, the orifice 425 can include an area that is about 50% or less of the area of the second tube 403 , or 40% or less of the area of the second tube 403 , or 30% or less of the area of the second tube 403 , or 20% or less of the area of the second tube 403 , or 10% or less of the area of the second tube 403 . The one or more orifices 423 can include several shapes, such as a circular cross-sectional shape, a quadrilateral cross-sectional shape (e.g., square, rectangular, etc.), a rounded, non-circular cross-sectional shape, etc. In some embodiments, the one or more orifices 423 can be arranged in a linear alignment (e.g., parallel to the tube axis 326 ), however, in other embodiments, other arrangements are also contemplated. In some embodiments, an orifice 425 of the one or more orifices 423 can extend along an axis 429 (e.g., between the inner and outer surfaces of the second sidewall 419 ), which intersects the closed first sidewall 409 , wherein the axis 429 extends intersectingly with the tube axis 326. In some embodiments, the axis 429 extends parallel to the travel path 305 .

In some embodiments, the cooling tube 327 can include a channel 431 between the closed first sidewall 409 and the second sidewall 419. For example, the second tube 403 can include a second cross-sectional dimension that is smaller than the first cross-sectional dimension of the first tube 401. In some embodiments, when the first tube 401 and the second tube 403 include a circular cross-sectional shape, the second tube 403 can include a second diameter that can be smaller than the first diameter of the first tube 401. The second sidewall 419 can be spaced a distance from the closed first sidewall 409 to define the channel 431 therebetween. As such, the channel 431 can be in fluid communication with the one or more orifices 423 and the second tube interior 422 . In some embodiments, the cooling tube 327 can be positioned to receive the cooling fluid 433 within the second tube 403 and pass the cooling fluid 433 through the one or more orifices 423 to the channel 431. For example, the second tube 403 can initially receive the cooling fluid 433 within the second tube interior 422. The cooling fluid can pass from the second tube interior 422 to the orifices 423. In some embodiments, as the cooling fluid 433 passes through the orifices 423 , the cooling fluid 433 can travel substantially parallel to the axis 429 , which can be orthogonal to the closed first sidewall 409 . Thus, after the cooling fluid 433 passes through the orifice 423 , the cooling fluid 433 can impact the inner surface of the closed first sidewall 409. Due in part to such impact of the cooling fluid 433 on the inner surface of the closed first sidewall 409 , the cooling fluid 433 can cool the closed first sidewall 409. In some embodiments, the cross-sectional dimensions of the orifice 425 and the one or more orifices 423 can be relatively small, so that the speed at which the cooling fluid 433 travels through the orifice 425 and the one or more orifices 423 can be relatively high, thereby ensuring that the cooling fluid 433 impacts the closed first sidewall 409 along the axis 429 . In contrast, when the orifice 425 and the one or more orifices 423 include a larger cross-sectional dimension, the velocity at which the cooling fluid 433 travels through the orifice 425 and the one or more orifices 423 can be relatively small, which can reduce the likelihood that the cooling fluid 433 will impact the closed first sidewall 409 along the axis 429. In some embodiments, the cooling tube 327 can receive the cooling fluid 433 within one of the second tube interior 422 or the channel 431 and pass the cooling fluid 433 through the orifice 425 of the one or more orifices 423 . For example, the cooling tube 327 can receive the cooling fluid 433 in the second tube interior 422 and pass the cooling fluid 433 through the orifice 425 to the channel 431 , or the cooling tube 327 can receive the cooling fluid 433 in the channel 431 and pass the cooling fluid 433 through the orifice 425 to the second tube interior 422 .

In some embodiments, more orifices 423 may be arranged along an axis parallel to the tube axis 326. For example, a first set of orifices 423 may be arranged at the top of the second tube 403 along an axis parallel to the tube axis 326. A second set of orifices 423 may be arranged at the bottom of the second tube 403 along another axis parallel to the tube axis 326. The second tube 403 is not limited to such a configuration. In some embodiments, the orifices 423 may be staggered along the second tube 403 between the proximal end 415 and the distal end 417 so that an axis may not intersect all of the orifices 423 at the top of the second tube 403 or another axis may not intersect all of the orifices 423 at the bottom of the second tube 403 . Additionally or alternatively, in some embodiments, an axis orthogonal to the tube axis 326 (e.g., axis 429 ) may intersect one of the orifices 423 but not both orifices 423. For example, as shown in FIG4 , the orifices 423 on opposite sides of the second tube 403 are arranged relative to each other such that the axis orthogonal to the tube axis 326 (axis 429 ) intersects two orifices, one orifice 423 located at the top of the second tube 403 and one orifice located at the bottom of the second tube 403 . However, such alignment of the orifices is not intended to be limiting, and in some embodiments, the orifices 423 on one side of the second tube 403 (e.g., such as at the top side) may be staggered relative to the orifices 423 on the opposite side of the second tube 403 (e.g., such as at the bottom side). In these embodiments, an axis (e.g., axis 429 ) orthogonal to the tube axis 326 may intersect one orifice (e.g., such as at the top side) but not the orifice on the opposite side (e.g., such as at the bottom side). Additionally or alternatively, in some embodiments, the orifices 423 are not limited to including the same size (e.g., as shown), and rather, some of the orifices 423 may include one size while other orifices 423 may include other sizes, and so on.

In some embodiments, a method of forming a strip 103 with a glass forming device 101 can include receiving a cooling fluid 433 within a second tube 403. For example, the second tube 403 can be coupled to a cooling fluid source, wherein the cooling fluid source delivers the cooling fluid source 433 to the second tube 403 in a second direction 439. The second tube 403 can include a second tube interior 422 , wherein the cooling fluid 433 is delivered through a proximal end 415 of the second tube 403 and into the second tube interior 422. In some embodiments, the cooling fluid 433 can include a gas, such as air, helium, and the like.

In some embodiments, a method of forming a strip 103 using a glass forming apparatus 101 may include directing a cooling fluid 433 through the one or more orifices 423 and through the channel 431 to cool the closed first sidewall 409. For example, the cooling fluid 433 may pass through the one or more orifices 423 when the cooling fluid 433 is received within the second tube interior 422. By passing through the one or more orifices 423 , the cooling fluid 433 may flow from the second tube interior 422 to the channel 431 , which may be located between the closed first sidewall 409 and the second sidewall 419 . As the cooling fluid 433 passes through the orifices 423 , the cooling fluid 433 may travel along the axis 429 so that the cooling fluid 433 may impact the inner surface of the closed first sidewall 409. In some embodiments, the step of directing the cooling fluid 433 through the one or more orifices 423 may include the step of maintaining the temperature of the outer surface 437 of the cooling tube 327 at from about 400° C. to about 600° C. For example, the cooling fluid 433 that may be delivered by the cooling fluid source may initially be at room temperature. As the cooling fluid 433 impinges upon the inner surface of the closed first sidewall 409 and flows through the channel 431 along the closed first sidewall 409 , the cooling fluid 433 may cool the outer surface 437 of the cooling tube 327. The method of forming the strip 103 using the glass forming device 101 may include the step of preventing the cooling fluid 433 from passing through the outer surface 437 of the cooling tube 327. For example, the cooling fluid 433 may be prevented from passing through the outer surface 437 of the cooling tube 327 because the closed first sidewall 490 and the closed first end 411 do not contain openings, orifices, gaps, vents, etc.

The effect of the cooling tube 327 on the temperature of the strip 103 (in °C) is shown below in Table 1. Column 1 shows the temperature of the strip 103 entering the upper housing portion 313 (e.g., entering at the top of the upper housing portion 313 ), while Column 2 shows the temperature of the strip 103 leaving the upper housing portion 313 (e.g., leaving at the bottom of the upper housing portion 313 ). Column 3 shows the average temperature of the strip 103 within the upper housing portion 313 , which is determined by the average of the temperatures of the strip 103 entering and leaving the upper housing portion 313 . The average temperature indicates the temperature of the strip 103 at the location where the strip 103 passes through the cooling tube 327 (e.g., where the first free path 329 intersects the location where the strip 103 passes through the cooling tube 327 ). Column 4 shows the temperature of the outer surface 437 of the cooling tube 327. Column 5 shows the difference between columns 3 and 4, i.e., the temperature difference between the average temperature of the strip 103 at the location where the strip 103 passes through the cooling tube 327 and the temperature of the outer surface 437 of the cooling tube 327. Column 5 shows whether unwanted strip 103 fluctuations are exhibited. Column 1 shows the effect when the temperature of the outer surface 437 of the cooling tube 327 is 200°C. Column 2 shows the effect when the temperature of the outer surface 437 of the cooling tube 327 is 300°C. Column 3 shows the effect when the temperature of the outer surface 437 of the cooling tube 327 is 400° C. Column 4 shows the effect when the temperature of the outer surface 437 of the cooling tube 327 is 500° C. Column 5 shows the effect when the temperature of the outer surface 437 of the cooling tube 327 is 600° C. Strip temperature (℃) Strip temperature (℃) leaving Strip temperature (℃) average Cooling tube outer surface temperature (℃) Temperature (℃) difference Band fluctuations? 1065 824 945 200 745 yes 1065 833 949 300 649 yes 1065 841 953 400 553 Sometimes 1065 853 959 500 459 no 1065 870 967 600 367 no Table 1

As shown in Table 1, when the outer surface 437 of the cooling tube 327 is maintained at a relatively low temperature (e.g., 200° C. or 300° C.), there may be fluctuations in the strip 103. In some embodiments, these fluctuations include thickness and/or viscosity changes in the strip 103. For example, when the outer surface 437 of the cooling tube 327 is maintained at 200° C., the temperature difference between the outer surface 437 of the cooling tube 327 and the average temperature of the strip 103 at the location where the strip 103 passes through the cooling tube 327 is 745° C., and there are strip fluctuations in the strip 103 . When the outer surface 437 of the cooling tube 327 is maintained at 300° C., the temperature difference between the outer surface 437 of the cooling tube 327 and the average temperature of the strip 103 at the location where the strip 103 passes through the cooling tube 327 is 649° C., and strip fluctuations exist in the strip 103. Table 1 further shows that when the outer surface 437 of the cooling tube 327 is maintained at a higher temperature (e.g., 400° C., 500° C., or 600° C.), there may be no fluctuations in the strip 103 . For example, when the outer surface 437 of the cooling tube 327 is maintained at 400° C., the temperature difference between the outer surface 437 of the cooling tube 327 and the average temperature of the strip 103 at the position where the strip 103 passes through the cooling tube 327 is 553° C., and strip fluctuations sometimes exist in the strip 103. When the outer surface 437 of the cooling tube 327 is maintained at 500° C., the temperature difference between the outer surface 437 of the cooling tube 327 and the average temperature of the strip 103 at the position where the strip 103 passes through the cooling tube 327 is 459° C., and no strip fluctuations exist in the strip 103 . When the outer surface 437 of the cooling tube 327 is maintained at 600° C., the temperature difference between the outer surface 437 of the cooling tube 327 and the average temperature of the strip 103 at the location where the strip 103 passes through the cooling tube 327 is 367° C., and there is no strip fluctuation in the strip 103. Therefore, in some embodiments, as the temperature difference between the outer surface 437 of the cooling tube 327 and the average temperature of the strip 103 at the location where the strip 103 passes through the cooling tube 327 decreases, the strip 103 is less likely to exhibit fluctuations while still being cooled within the upper housing portion 313 .

In some embodiments, a method of forming a strip 103 using a glass forming apparatus 101 may include flowing a cooling fluid 433 through a cooling tube 327 such that a temperature difference between the strip 103 and an outer surface 437 of the cooling tube 327 at a location where the strip 103 passes through the cooling tube 327 is less than about 649° C. For example, as shown in FIG3 , a first free path 329 may intersect a travel path 305 at a location where the strip 103 passes through the cooling tube 327. In some embodiments, an outer surface 437 of the cooling tube 327 may be maintained at a temperature of from about 400° C. to about 600° C. due to the cooling fluid 433 flowing through the second tube 403 , the one or more orifices 423 , and the channel 431 of the first tube 401 . For example, flowing the cooling fluid 433 through the cooling tube 327 may include receiving a gas within the cooling tube 327. As a result, the temperature of the cooling tube 327 may be lower than the temperature of the strip 103 where the strip 103 passes through the cooling tube 327 , wherein the temperature difference is less than about 649° C. In some embodiments, flowing the cooling fluid 433 through the cooling tube 327 causes the temperature difference between the strip 103 where the strip 103 passes through the cooling tube 327 and the outer surface 437 of the cooling tube 327 to be less than about 553° C. In some embodiments, the cooling fluid 433 is flowed through the cooling tube 327 such that the temperature difference between the strip 103 at the location where the strip 103 passes through the cooling tube 327 and the outer surface 437 of the cooling tube 327 is less than about 459°C.

In some embodiments, a method of forming a strip 103 using a glass forming apparatus 101 may include removing a cooling fluid 433 from a channel 431 along a first direction 435 that is opposite to a second direction 439 along which the cooling fluid 433 flows within the second tube 403. For example, directing the cooling fluid 433 through the channel 431 may include directing the cooling fluid 433 along a removal path 441 that may be substantially parallel to the axis 326 along which the second tube 403 extends. In some embodiments, the removed cooling fluid 433 may be collected and reinjected through the second tube 403 , for example, after filtering and/or cooling. In some embodiments, the cooling fluid 433 is not limited to flowing within the second tube interior 422 before passing through the orifices 423 to the first tube interior 413. Rather, in some embodiments, the cooling fluid 433 can flow in an opposite direction than as previously described. For example, the cooling fluid 433 can initially enter the cooling tube 327 by flowing in the second direction 439 and flowing into the first tube interior 413. The cooling fluid 433 can then flow from the first hollow tube interior 413 through the one or more orifices 423 to the second hollow tube interior 422. The cooling fluid 433 can then flow along the first direction 435 during removal from the second hollow tube interior 422 .

6 , an additional embodiment of a cooling tube 601 in the one or more cooling tubes 325 along line 4-4 of FIG . 3 is illustrated. The structure and function of the cooling tube 601 can be similar to the cooling tube 327. For example, the cooling tube 601 can include a first tube 401 and a second tube 403 , wherein the second tube 403 includes an orifice 425. In some embodiments, the orifice 425 can extend between the proximal end 415 and the distal end 417 along about 50% or more of the length of the second tube 403 . For example, the orifice 425 may include a single high aspect ratio slot that extends along a portion of the length of the second tube 403 , such as 50% or more of the length, 60% or more of the length, 70% or more of the length, 80% or more of the length, or 90% or more of the length. In some embodiments, the width of the orifice 425 may be relatively small (e.g., where the length of the orifice 425 may be 50% or more of the length of the second tube 403 , but the width is relatively small and/or thin), such that the velocity at which the cooling fluid 433 travels through the orifice 425 may be relatively high. In contrast, when the orifice 425 includes a larger width, the velocity at which the cooling fluid 433 travels through the orifice 425 may be relatively low.

7 illustrates the relationship between time and temperature fluctuation of strip 103. The x -axis (e.g., horizontal axis) represents time (e.g., seconds), and the y-axis (e.g., vertical axis) represents temperature fluctuation (e.g., °C). A first line 701 represents the temperature fluctuation of strip 103 across the width of strip 103 when the cooling tubes (e.g., 325 , 327 ) in upper housing portion 313 are maintained at approximately 200°C. A second line 703 represents the temperature fluctuation of strip 103 across the width of strip 103 when the cooling tubes (e.g., 325 , 327 ) in upper housing portion 313 are maintained at approximately 500° C . In these embodiments, when the cooling tubes (e.g., 325 , 327 ) are maintained at a relatively cool temperature, the strip 103 exhibits a relatively high degree of temperature fluctuation, as represented by the first line 701. That is, when the cooling tubes (e.g., 325 , 327 ) are maintained at approximately 200°C, the strip 103 will exhibit a relatively high degree of temperature fluctuation over time. In contrast, when the cooling tubes (e.g., 325 , 327 ) are maintained at a relatively high temperature, the strip 103 exhibits a relatively low degree of temperature fluctuation, as represented by the second line 703 . That is, when the cooling tubes (eg, 325 , 327 ) are maintained at approximately 500°C, the strip 103 will exhibit a relatively low degree of temperature fluctuation over time.

In some embodiments, the glass cooling device 301 can provide improved cooling of the strip 103 with the one or more cooling tubes 325. For example, by maintaining the one or more cooling tubes 325 at a temperature of from about 400° C. to about 600° C. and by providing a free path between the one or more cooling tubes 325 and the strip 103 , certain negative effects can be reduced. For example, these effects can include temperature fluctuations within the upper housing chamber 317 , air flow around the strip 103 , convection drums, etc. As a result of reducing these effects, the likelihood of thickness and viscosity variations occurring within the strip 103 can likewise be reduced. Additionally or alternatively, the structure of the one or more cooling tubes 325 may similarly produce improvements with respect to maintaining the temperature within the upper housing chamber 317. For example, the one or more cooling tubes 325 may include a closed first sidewall 409 and a closed first end 411 , thereby restricting the cooling fluid 433 from escaping the one or more cooling tubes 325 and flowing into the upper housing chamber 317. Thus, by containing the cooling fluid 433 within the one or more cooling tubes 325 , air flow within the upper housing chamber 317 may be further reduced. The type of cooling fluid 433 used within the one or more cooling tubes 325 is also beneficial in a number of ways. For example, the cooling fluid 433 may include a gas, which does not evaporate when exposed to relatively high temperatures like water. Similarly, since the cooling fluid 433 includes a gas, wear and tear of the first tube 401 (e.g., the closed first sidewall 409 and the closed first end 411 ) and the second tube 403 (e.g., the second sidewall 419 and the closed second end 421 ) can be reduced, which wear and tear can be amplified by using a liquid or water as the cooling fluid 433. For example, compared to using a gas as the cooling fluid 433 , using a liquid or water as the cooling fluid 433 may cause additional corrosion of the first tube 401 and/or the second tube 403 .

Therefore, the following non-limiting examples are exemplary of the present disclosure.

Embodiment 1. A glass forming apparatus may include: a cooling tube, including: a first tube including a closed first sidewall and a closed first end; and a second tube including a closed second end and a second sidewall, the second sidewall defining an orifice, the second tube being positioned within the first tube, the cooling tube including a channel between the closed first sidewall and the second sidewall, the cooling tube being configured to receive a cooling fluid in one of the second tube or the channel and pass the cooling fluid through the orifice.

Embodiment 2. The glass forming apparatus of Embodiment 1, wherein one or more of the first tube or the second tube comprises a cylindrical shape.

Embodiment 3. The glass forming apparatus of any one of Embodiments 1-2, wherein the second tube is coaxial with the first tube.

Embodiment 4. The glass forming device of any of Embodiments 1-3, wherein the orifice comprises a plurality of orifices.

Embodiment 5. The glass forming device of any of Embodiments 1-3, wherein the orifice extends along about 50% or more of the length of the second tube.

Embodiment 6. The glass forming device of any of Embodiments 1-3, wherein the orifice extends along about 50% or less of the length of the second tube.

Embodiment 7. The glass forming apparatus of any one of Embodiments 1-6, wherein the cooling fluid comprises a gas.

Embodiment 8. A glass forming apparatus may include an upper housing portion, a travel path defined by the glass forming apparatus extending within the upper housing portion, the upper housing portion including a cooling tube, wherein a first free path extends between the cooling tube and the travel path in a first free path direction orthogonal to the travel path.

Embodiment 9. The glass forming apparatus of embodiment 8, wherein the cooling tube comprises: a first tube including a closed first sidewall and a closed first end; and a second tube including a closed second end and a second sidewall, the second sidewall defining the orifice, the second tube being positioned within the first tube, the cooling tube including a channel between the closed first sidewall and the second sidewall, the cooling tube being configured to receive a cooling fluid within one of the second tube or the channel and to pass the cooling fluid through the orifice.

Embodiment 10. The glass forming device as described in any one of Embodiments 8-9, wherein the travel path extends into a lower shell portion positioned below the upper shell portion, the lower shell portion further includes a lower cooling tube and a second free path, the second free path extending between the lower cooling tube and the travel path in a second free path direction.

Embodiment 11. The glass forming device as described in Embodiment 10, wherein the first free path direction is substantially parallel to the second free path direction.

Embodiment 12. A glass forming apparatus as described in any of Embodiments 9-11, wherein the temperature difference between the strip and the outer surface of the cooling tube at the location where the strip passes through the cooling tube is less than about 649°C.

Example 13. A method of forming a strip using the glass forming apparatus described in Example 1 may include the steps of moving the strip through the cooling tube along a travel path in a travel direction. The method may include the steps of receiving the cooling fluid in the second tube. The method may include the steps of directing the cooling fluid through the orifice and through the channel to cool the closed first side wall.

Embodiment 14. The method of embodiment 13, wherein the step of directing the cooling fluid through the orifice comprises the following steps: maintaining the temperature of the outer surface of the cooling tube at from about 400°C to about 600°C.

Embodiment 15. The method as described in any one of Embodiments 13-14 further includes the following step: removing the cooling fluid from the channel along a first direction, the first direction being opposite to a second direction along which the cooling fluid flows in the second tube.

Embodiment 16. The method as described in Embodiment 15, wherein the step of removing the cooling fluid comprises the following steps: guiding the cooling fluid along a removal path, the removal path being substantially parallel to the axis along which the second tube extends.

Example 17. A method of forming a strip using the glass forming apparatus may include the steps of moving the strip through a cooling tube along a travel path in a travel direction. The method may include the steps of flowing a cooling fluid through the cooling tube so that the temperature difference between the strip and the outer surface of the cooling tube at the location where the strip passes through the cooling tube is less than about 649°C.

Embodiment 18. The method as described in Embodiment 17 further includes the following step: preventing the cooling fluid from passing through the outer surface of the cooling tube.

Embodiment 19. The method of any one of Embodiments 17-18, wherein the step of flowing the cooling fluid through the cooling tube causes the temperature difference between the strip at the position where the strip passes through the cooling tube and the outer surface of the cooling tube to be less than about 553°C.

Embodiment 20. The method of any one of Embodiments 17-19, wherein the step of flowing the cooling fluid through the cooling tube causes the temperature difference between the strip at the position where the strip passes through the cooling tube and the outer surface of the cooling tube to be less than about 459°C.

As used herein, the terms "the" or "an" mean "one or more" and should not be limited to "only one" unless clearly indicated to the contrary. For example, reference to "an element" therefore includes embodiments having two or more such elements unless the context clearly indicates otherwise.

As used herein, the term "about" means that quantities, dimensions, formulations, parameters, and other quantities and characteristics are not or need not be exact, but may be approximate and/or larger or smaller as desired reflecting tolerances, conversion factors, rounding, measurement errors, etc., and other factors known to those skilled in the art. When the term "about" is used to describe a value or an endpoint of a range, the disclosure should be understood to include the specific value or endpoint referred to. Regardless of whether a value or a range endpoint in this specification is stated as "about," the value or range endpoint is intended to include two embodiments: one modified by "about" and one not modified by "about." It will be further understood that each of the endpoints in the range is significant compared to the other endpoint and is significant independently of the other endpoint.

As used herein, the terms "substantial," "essentially," and variations thereof are intended to describe that a characteristic is equal to or nearly equal to a value or description. For example, a "substantially flat" surface is intended to indicate a flat or nearly flat surface. And, as defined above, "substantially similar" is intended to indicate that two values are equal or nearly equal. In some embodiments, "substantially similar" may indicate values that are within about 10% of each other, such as values that are within about 5% of each other, or values that are within about 2% of each other.

As used herein, the terms "include" and variations thereof should be interpreted as being synonymous and open-ended unless otherwise indicated.

It should be appreciated that although various embodiments have been described in detail with respect to certain illustrative and specific embodiments of the embodiments, the present disclosure should not be considered limited thereto, since many variations and combinations of the disclosed features are contemplated without departing from the scope of the following claims.

100: Glass manufacturing device 101: Forming device 102: Glass melting and delivery device 103: Strip 104: Glass sheet 105: Melting container 107: Batch material 109: Storage rack 111: Batch delivery device 113: Motor 115: Controller 117: Arrow 119: Melt probe 121: Molten material 123: Vertical pipe 125: Communication line 127: Clarifying container 129: First connecting conduit 131: Mixing chamber 133: Delivery container 135: Second connecting conduit 137: Third connecting conduit 139: Delivery pipe 140: Forming container 141: inlet conduit 145: root 149: glass separator 151: separation path 152: center portion 153: first outer edge 154: drawing direction 155: second outer edge 156: direction 163: edge guide 164: edge guide 201: flow channel 203: weir 204: weir 205: outer surface 206: outer surface 207: downwardly inclined convergent surface portion 208: downwardly inclined convergent surface portion 209: forming wedge 210: opposite end 211: opposite end 213: drawing plane 215: first main surface 216: second main surface 301: Glass cooling device 303: Cooling door 305: Travel path 307: Cooling tube 309: Impact hot plate 311: Shell 313: Upper shell part 315: Lower shell part 317: Upper shell chamber 319: Travel direction 321: Upper shell wall 325: Cooling tube 326: tube axis 327: cooling tube 329: first free path 331: first free path direction 335: partition member 341: lower shell chamber 343: lower shell wall 345: lower cooling tube 347: lower cooling tube 348: lower tube axis 349: second free path 351: first free path direction Two free path directions 401: First tube 403: Second tube 405: Proximal end 407: Distal end 409: Closed first side wall 411: Closed first end 413: Inside of first tube 415: Proximal end 417: Distal end 419: Second side wall 421: Closed second end 422: Inside of second tube 423: Orifice 425: Orifice 429: Axis 431: Channel 433: Cooling fluid 435: First direction 437: External surface 439: Second direction 441: Removal path 601: Cooling tube 701: First line 703: Second line T: Thickness W: Width

These and other features, embodiments and advantages will be better understood upon reading the following detailed description with reference to the accompanying drawings, in which:

FIG. 1 schematically illustrates an exemplary embodiment of a glass forming apparatus according to an embodiment of the present disclosure;

FIG. 2 illustrates a perspective cross-sectional view of a glass forming apparatus along line 2-2 of FIG . 1 according to an embodiment of the present disclosure;

FIG. 3 depicts a cross-sectional view along line 3-3 of FIG . 2 of an exemplary embodiment of a glass cooling device according to an embodiment of the present disclosure;

FIG. 4 depicts a cross-sectional view along line 4-4 of FIG . 3 of an exemplary embodiment of a cooling tube according to an embodiment of the present disclosure;

FIG. 5 illustrates a cross-sectional view of the cooling tube of FIG . 4 along line 5-5 of FIG. 4 according to an embodiment of the present disclosure;

FIG6 illustrates a cross-sectional view along line 4-4 of FIG3 of an additional embodiment of a cooling tube according to an embodiment of the present disclosure ; and

FIG. 7 is a graph showing some embodiments of time and temperature fluctuations of a glass strip.

Domestic storage information (please note the storage institution, date, and number in order) None

Overseas storage information (please note the storage country, institution, date, and number in order) None

101: forming device

103: Stripe

145: Roots

201: Flow channel

209: Forming a wedge

215: First main aspect

216: Second main aspect

301: Glass cooling device

303: Cold Door

305: Travel path

307: Cooling tube

309: Hot plate

311: Shell

313: Upper shell part

315: Lower shell part

317: Upper shell chamber

319: Direction of travel

321: Upper shell wall

325: Cooling tube

326: Pipe shaft

327: Cooling tube

329: First free path

331: Path direction

335:Separating member

341: Lower housing chamber

343: Lower shell wall

345: Lower cooling tube

347: Lower cooling tube

348: Lower tube shaft

349: Second free path

351: Second free path direction

Claims (9)

A glass forming device, comprising: at least one cooling tube, arranged in a shell of a glass cooling device, extending in the shell through a path defined by the glass forming device; wherein the at least one cooling tube comprises: a first tube, comprising a closed first side wall and a closed first end; and a second tube, comprising a closed second end and a second side wall, the second side wall defining an orifice, the second tube being positioned in the first tube, the at least one cooling tube comprising a channel between the closed first side wall and the second side wall, the at least one cooling tube being configured to receive a cooling fluid in one of the second tube or the channel and to pass the cooling fluid through the orifice. A glass forming device as described in claim 1, wherein one or more of the first tube or the second tube comprises a cylindrical shape. A glass forming device as described in claim 1, wherein the second tube is coaxial with the first tube. A glass forming device as described in claim 1, wherein the orifice extends along about 50% or more of a length of the second tube. A glass forming device, comprising: a forming wedge; a cooling door positioned adjacent to a root portion of the forming wedge and including a first cooling tube and a hot plate, the first cooling tube being configured to contain a cooling fluid and direct the cooling fluid toward the hot plate; an upper shell portion positioned below the cooling doors, a travel path defined by the glass forming device extending within the upper shell portion, the upper shell portion including a second cooling tube, wherein a first free path extends between the second cooling tube and the travel path in a first free path direction orthogonal to the travel path, and wherein the first free path is unobstructed and is located between the second cooling tube and the travel path. There is no intervening structure between the travel path; and wherein the second cooling tube comprises: a first tube including a closed first sidewall and a closed first end; and a second tube including a closed second end and a second sidewall, the second sidewall defining an orifice, the second tube being positioned within the first tube so that the second tube is coaxial with the first tube extending along a tube axis parallel to the travel path, the second cooling tube comprising a channel between the closed first sidewall and the second sidewall, the second cooling tube being configured to receive a cooling fluid within one of the second tube or the channel and to pass the cooling fluid through the orifice, the first tube comprising a thermally conductive material. A glass forming device as described in claim 5, wherein the travel path extends into a lower shell portion positioned below the upper shell portion, the lower shell portion further comprising a lower cooling tube and a second free path, the second free path extending between the lower cooling tube and the travel path in a second free path direction. A glass forming device as described in claim 6, wherein the first free path direction is substantially parallel to the second free path direction. A method of forming a strip using a glass forming apparatus as described in claim 1, the method comprising the steps of: moving the strip through the cooling tube along a travel path in a travel direction; receiving the cooling fluid in the second tube; and directing the cooling fluid through the orifice and through the channel to cool the closed first side wall. The method as described in claim 8 further includes the following steps: removing the cooling fluid from the channel along a first direction, the first direction being opposite to a second direction along which the cooling fluid flows in the second tube.