GB1137893A - Method and apparatus for dividing glass sheets - Google Patents

Abstract

1,137,893. Dividing glass sheets. GLAVERBEL. 4 March, 1966 [5 March, 1965], No. 9685/66. Heading C1M. In a method of breaking glass sheets along pre-scored lines, one side of the sheet, over an area containing such lines, is subjected to an elastic pressure in excess of any pressure prevailing on the other side of the sheet, while restraining movement of the sheet at the periphery of said area, so that the sheet flexes and breaks. Preferably the sheet is clamped around the whole of the periphery of said area. Pre-scored glass sheets 14 are fed off delivery rolls 26 on to a flexible continuous belt 20 and are conveyed above the perforated top wall 2 of a chamber 1. The chamber is connected to a source of air under pressure and is also vented to atmosphere. As the sheet 14 leaves rolls 26 it contacts a sensing device 41 which initiates the breaking sequence through a control circuit. The sheet is halted above the chamber 1 and then a rigid membrane 32 mounted upon a vertically movable frame is lowered into contact with the sheet thereby rigidly holding the sheet, at its margins only, against the perforated wall 2 and conveyer 20. Air is then introduced into chamber 1 and this causes the sheet 14 to flex away from chamber 1 and thus break along the scored lines. The chamber 1 is then vented to atmosphere, membrane 32 raised and the divided glass sheets conveyed away. Other simpler forms of apparatus are also disclosed in one of which the perforated wall 2 is flexible. The control circuit essentially comprises a magnetic disk rotating at a constant angular velocity on which a signal is recorded when a sensing device detects the leading edge of a glass sheet. This signal is then moved in sequence past a plurality of reading heads which activate circuits controlling the various operations. At the end the signal is erased.