JPS6424034A - Method for bending sheet glass - Google Patents

Abstract

PURPOSE:To easily and precisely bend sheet glass by press-forming the heated sheet glass between the lower die consisting of a peripheral die and a central die and the upper die, lowering the central die to hold the sheet glass with the peripheral die, and allowing the sheet glass to cool in the air. CONSTITUTION:The thin sheet glass G heated by a heating furnace 2 to a temp. close to the softening point is carried into a forming device 1 by a carrier roller 10. The upper die 3 with the lower surface as a forming surface is lowered by a cylinder unit 7. The lower die 4 consisting of the peripheral die 4a and the central die 4b and with the upper surface as the forming surface is simultaneously raised by cylinder units 8 and 9. By this process, the thin sheet glass G is bent between the upper and lower dies 3 and 4. The upper die 3 is then raised, the central die 4b is lowered to hold the bent thin sheet glass G by the peripheral die 4a of the lower die 4, and the sheet glass G is allowed to cool in the air or cooled at a rate close to the natural cooling. By this method, the thin sheet glass is accurately press-formed into a three- dimensional bent shape without causing the transfer of a cross mark, etc.