Glass forming apparatuses having infrared-transparent barriers and methods of cooling glass using the same

Patent metadata

Field	Value
Publication number	US-2021355015-A1
Application number	US-201917282252-A
Country	US
Kind code	A1
Filing date	Sep 30, 2019
Priority date	Oct 5, 2018
Publication date	Nov 18, 2021
Grant date	—

Abstract

Embodiments of glass forming apparatuses are disclosed herein. In one embodiment, a glass forming apparatus may include a forming body defining a draw plane extending from the forming body in a draw direction. An actively-cooled thermal sink may be positioned below the forming body in the draw direction and spaced apart from the draw plane. An infrared-transparent barrier may be positioned between the actively-cooled thermal sink and the draw plane. The infrared-transparent barrier may comprise an infrared-transparent wall positioned proximate the actively-cooled thermal sink or an infrared-transparent jacket positioned around the actively-cooled thermal sink.

First claim

What is claimed is:

1 . A glass forming apparatus, comprising:
a forming body defining a draw plane extending from the forming body in a draw direction; an actively-cooled thermal sink positioned below the forming body in the draw direction and spaced apart from the draw plane; and an infrared-transparent barrier positioned between the actively-cooled thermal sink and the draw plane.

2 . The glass forming apparatus of claim 1 , further comprising:
a thickness control member positioned below the forming body in the draw direction; and a baffle positioned in the draw direction from the actively-cooled thermal sink, the actively-cooled thermal sink and the infrared-transparent barrier positioned between the thickness control member and the baffle.

3 . The glass forming apparatus of claim 2 , wherein the baffle extends toward the draw plane.

4 . The glass forming apparatus of claim 2 , wherein the thickness control member comprises a slide gate and a cooling door positioned in the draw direction from the slide gate.

5 . The glass forming apparatus of claim 1 , wherein the infrared-transparent barrier comprises an infrared-transparent wall positioned between the actively-cooled thermal sink and the draw plane.

6 . The glass forming apparatus of claim 1 , wherein the infrared-transparent barrier comprises an infrared-transparent jacket positioned around at least a portion of the actively-cooled thermal sink.

7 . The glass forming apparatus of claim 1 , wherein the infrared-transparent barrier comprises a material with an infrared transmittance greater than or equal to 30% at wavelengths from about 0.5 μm to about 6 μm.

8 . The glass forming apparatus of claim 1 , wherein the infrared-transparent barrier is spaced apart from the actively-cooled thermal sink.

9 . A method of forming a glass ribbon comprising:
drawing the glass ribbon from a forming body in a draw direction; cooling the glass ribbon by passing the glass ribbon past an actively-cooled thermal sink positioned below the forming body in the draw direction, an infrared-transparent barrier positioned between the actively-cooled thermal sink and the draw plane; and stabilizing eddies of air that circulate adjacent to the glass ribbon.

10 . The method of claim 9 , wherein the eddies of air are stabilized by reducing cooling of air in the eddies of air with the infrared-transparent barrier.

11 . The method of claim 9 , wherein the infrared-transparent barrier comprises an infrared-transparent wall positioned between the actively-cooled thermal sink and the glass ribbon.

12 . The method of claim 9 , wherein the infrared-transparent barrier comprises an infrared-transparent jacket positioned around at least a portion of the actively-cooled thermal sink.

13 . The method of claim 9 , wherein the infrared-transparent barrier comprises a material with an infrared transmittance greater than or equal to 30% at wavelengths from about 0.5 μm to about 6 μm.

14 . The method of claim 9 , wherein the infrared-transparent barrier is spaced apart from the actively-cooled thermal sink.

15 . The method of claim 9 , wherein the actively-cooled thermal sink is maintained at a temperature less than a temperature of the infrared-transparent barrier.

16 . The method of claim 9 , wherein:
a thickness control member is positioned below the forming body in the draw direction; a baffle is positioned in the draw direction from the actively-cooled thermal sink, the actively-cooled thermal sink and the infrared-transparent barrier positioned between the thickness control member and the baffle, the baffle and the thickness control member bounding a partially enclosed region; and the eddies of air circulate in the partially enclosed region.

17 . The method of claim 16 , wherein the thickness control member comprises a slide gate and a cooling door positioned below the slide gate in the draw direction from the slide gate.

18 . The method of claim 16 , wherein the glass ribbon is in a viscous or a viscoelastic state within the partially enclosed region.

19 . The method of claim 16 , wherein a temperature variation of air measured at a fixed location in the partially enclosed region is less than 0.4° C. over 10 seconds.

20 . The method of claim 16 , wherein a temperature variation of air measured at a fixed location in the partially enclosed region is less than 0.2° C. over 10 seconds.

Assignees

• Corning Inc

Inventors

• Aburada Tomohiro
• Agrawal Anmol
• Meng Jiandong
• Peng Gaozhu

Classifications

• C03B17/067 Primary

  combined with thermal conditioning of the sheets · CPC title

• C03B25/087

  being in a vertical position · CPC title

• C03B17/064 Primary

  by the overflow downdraw fusion process; Isopipes therefor · CPC title

• Y02P40/57

  Improving the yield, e-g- reduction of reject rates · CPC title

• C03B15/12

  Construction of the annealing tower · CPC title