Patent · US Expired

Thermal treatment of glass sheets

US4221579A · kind A · utility

3Cited by
2References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 19, 1979
Grant dateSep 9, 1980
Priority date
Expiry dateApr 19, 1999

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC03B27/052
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A glass sheet is thermally treated, for example thermally toughened, by heating the glass sheet, and lowering the sheet into a gas-fluidized bed of particulate material which is at a glass-treatment temperature, for example quenching temperature. Extraction of gas from a localized upper region of the bed is commenced prior to the lowering of the hot glass sheet into the bed in order to produce gradually an unfluidized static packed condition of the material in that upper region of the bed. The glass sheet is lowered into the bed at a time after commencement of gas extraction which is such that the lower edge of the sheet passes through that upper region prior to full attainment of the static packed condition.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.