Methods for producing a glass ribbon

Patent metadata

Field	Value
Publication number	US-2016016838-A1
Application number	US-201414334108-A
Country	US
Kind code	A1
Filing date	Jul 17, 2014
Priority date	Jul 17, 2014
Publication date	Jan 21, 2016
Grant date	—

Abstract

Methods for producing a glass ribbon include the step of drawing a glass ribbon from a quantity of molten glass and detecting an instability in the glass ribbon. In response to the detected instability, the method can further include the step of automatically adjusting an operating variable for each of a plurality of stabilizing elements simultaneously with a controller to at least partially counter the detected instability.

First claim

What is claimed is:

1 . A method for producing a glass ribbon comprising:
(I) drawing a glass ribbon from a quantity of molten glass in a draw direction, wherein the glass ribbon includes a width extending along a profile axis perpendicular to the draw direction between a first edge and a second edge of the glass ribbon, the glass ribbon further includes a thickness extending between a first major surface and a second major surface of the glass ribbon, and a plurality of thermal elements positioned along the profile axis, wherein each thermal element includes an adjustable operating variable; (II) providing the glass ribbon with a first temperature profile along the profile axis; and (III) automatically adjusting the adjustable operating variable of each thermal element simultaneously with a controller based on an input into the controller to maintain the first temperature profile or automatically change the first temperature profile to a second temperature profile that is predetermined.

2 . The method of claim 1 , wherein step (III) adjusts the adjustable operating variable of each thermal element to automatically change the first temperature profile to a second temperature profile that is predetermined.

3 . The method of claim 2 , wherein the input of step (III) represents an instability in the process of drawing the glass ribbon.

4 . The method of claim 3 , wherein the instability comprises a discontinuity of the glass ribbon.

5 . The method of claim 2 , wherein the second temperature profile is higher in temperature than the first temperature profile.

6 . The method of claim 2 , wherein the controller is in communication with a plurality of predetermined temperature profiles and, during step (III), the controller selects the second temperature profile from the plurality of predetermined temperature profiles based on the input.

7 . The method of claim 1 , wherein the plurality of thermal elements comprise a plurality of heating elements and the adjustable operating variable of each heating element comprises a heating parameter of the heating element.

8 . A method for producing a glass ribbon comprising:
(I) drawing a glass ribbon from a quantity of molten glass; (II) detecting an instability in the glass ribbon; and in response to detecting the instability, (III) automatically adjusting an operating variable for each of a plurality of stabilizing elements simultaneously with a controller to at least partially counter the detected instability.

9 . The method of claim 8 , wherein during step (I), the controller operates the stabilizing elements with a first operating profile.

10 . The method of claim 9 , wherein during step (III), the first operating profile of the stabilizing elements is automatically switched by the controller to a second operating profile to at least partially counter the detected instability.

11 . The method of claim 10 , wherein the controller is in communication with a plurality of predetermined operating profiles and, during step (III), the controller selects the second operating profile from the plurality of predetermined operating profiles based on the input.

12 . The method of claim 10 , wherein the first operating profile facilitates maintenance of a first thickness of the glass ribbon and the second operating profile facilitates maintenance of a second thickness of the glass ribbon that is predetermined and greater than the first thickness.

13 . The method of claim 10 , wherein after step (III), further comprising,
(IV) detecting a stability in the glass ribbon; and then in response to detecting the stability, (V) automatically switching the second operating profile of the stabilizing elements back to the first operating profile with the controller.

14 . The method of claim 8 , wherein step (III) at least partially counters the detected instability by adjusting the operating variable for each of the plurality of stabilizing elements to increase a thickness of the glass ribbon.

15 . The method of claim 8 , wherein the instability detected during step (II) comprises a discontinuity in the glass ribbon.

16 . The method of claim 8 , wherein the stabilizing elements each comprise a thermal element.

17 . The method of claim 16 , wherein the operating variable for each of the stabilizing elements comprises a heating parameter of the thermal element, and step (III) at least partially counters the detected instability by adjusting the heating parameter of the thermal element to increase a temperature of the glass ribbon.

18 . The method of claim 8 , wherein the stabilizing elements each comprise a pulling roll.

19 . The method of claim 18 , wherein the operating variable for each of the stabilizing elements comprises a contact status of the pulling roll with the glass ribbon, wherein during step (III) the contact status of the pulling roll is automatically switched by the controller from an engaged position wherein the pulling roll contacts the glass ribbon to a disengaged position wherein the pulling roll is not in contact with the glass ribbon.

20 . The method of claim 18 , wherein the operating variable for each of the stabilizing elements comprises a pulling roll speed of the pulling roll.

Assignees

• Corning Inc

Inventors

• Aburada Tomohiro
• Amadon Jeffrey Robert
• Berkey Adam Charles
• Horsfall Terrence Richard
• Kudva Gautam Narendra
• Nishimoto Michael Yoshiya

Classifications

• C03B17/064 Primary

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

• C03B17/067 Primary

  combined with thermal conditioning of the sheets · CPC title

• C03B17/068

  Means for providing the drawing force, e.g. traction or draw rollers · CPC title

• Y02P40/57

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