US 12,319,606 B2
Device and method for length cutting in ultrathin glasses
Holger Wegener, Alfeld (DE); Rainer Schwertfeger, Eschershausen (DE); Michael Maedje, Grünenplan (DE); Christian Diekmann, Grünenplan (DE); and Markus Langer, Grünenplan (DE)
Assigned to SCHOTT AG, Mainz (DE)
Filed by SCHOTT AG, Mainz (DE)
Filed on Jul. 14, 2021, as Appl. No. 17/376,076.
Claims priority of application No. 10 2020 118 532.4 (DE), filed on Jul. 14, 2020.
Prior Publication US 2022/0017401 A1, Jan. 20, 2022
Int. Cl. C03B 33/023 (2006.01); C03B 33/03 (2006.01); C03B 33/033 (2006.01); C03B 33/037 (2006.01); C03B 35/14 (2006.01)
CPC C03B 33/0235 (2013.01) [C03B 33/03 (2013.01); C03B 33/033 (2013.01); C03B 33/037 (2013.01); C03B 35/14 (2013.01)] 23 Claims
OG exemplary drawing
 
22. A method for producing glass ribbon portions comprising:
a) hot forming a continuous glass ribbon with a ribbon thickness (d) in a range from 15 μm to 150 μm from a glass melt in a hot forming device, wherein the ribbon has edgings of thickened edge regions and an interior flat region;
b) cooling the glass ribbon at a cooling rate that is dependent on the ribbon thickness (d), wherein the cooling rate lies in the range from (1/d)*5 K/min*μm to (1/d)*280 K/min*μm;
c) transporting the glass ribbon at a velocity (v1);
d) redirecting the glass ribbon into a first plane E1 and transporting the glass ribbon along the first plane E1 in a transport direction at the velocity v1, wherein the transport direction having the velocity v1 is parallel to the edges of the glass ribbon;
e) inserting a score only in a thickened edge region made by a scoring tool at an angle (α) to the transport direction of the glass ribbon in at least one of the thickened edge regions, and wherein the score does not extend over the entire width of the glass ribbon;
f) deflecting the glass ribbon from the first plane E1 to a second plane E2, wherein the glass ribbon is transported in the second plane E2 at a velocity v2>0, wherein the first and second planes are angled with respect to one another and/or have a height difference with respect to one another, so a zone with bending stress with a main stress line is introduced in the glass ribbon, when the glass ribbon is transferred from the first plane E1 to the second plane E2, wherein the bending stress is set by the difference in position between the first plane E1 and the second plane E2 and/or the difference between the velocities v1 and v2, and wherein when the score enters the zone having the bending stress, a spontaneous cracking at the score occurs and a crack runs along the main stress line and forms edges, thereby separating a portion of the glass ribbon edges in the extension of the score across the glass ribbon in a lateral direction.