Method and apparatus for producing heat-strengthened glass sheets having improved break patterns

Apparatus for heat strengthening glass sheets comprising:

• a furnace;
• a quenching station mounted adjacent an exit end of the furnace wherein said quenching station includes:
• first means mounted on each side of the path of travel for directing tempering medium toward the path of travel;
• baffle means mounted between said first directing means and adjacent side of the path of travel, said baffle means including a plate comprising:
• an imperforate portion facing only a center portion of the path of travel to restrict flow of tempering medium toward the center portion of the path, and
• an apertured portion having apertures beyond each transverse end of said imperforate portion facing lateral side portions of the path of travel to permit flow of quenching medium through said apertures toward the lateral side portions only of the path of travel to establish a temperature gradient in the sheet moving between said first directing means transverse to the path of travel;
• second means mounted on each side of the path of travel downstream of said first directing means for directing quenching medium toward the path of travel between said second directing means to provide heat strengthened glass with a predetermined break pattern;
• and
• means for moving a glass sheet along a path of travel through the furnace and said quenching station.

Apparatus for establishing a desired temperature gradient in glass sheets comprising:

• a furnace;
• a quenching station mounted adjacent an exit end of the furnace wherein said quenching station includes:
• means mounted on each side of the path of travel for directing tempering medium toward the path of travel,
• baffle means mounted between said directing means and adjacent side of the path of travel, said baffle means including a plate comprising:
• an imperforate portion facing only a center portion of the path of travel to restrict flow of tempering medium toward the center portion of the path;
• and
• an apertured portion having apertures beyond each transverse end of said imperforate portion facing lateral side portions of the path of travel to permit flow of quenching medium through said apertures toward the lateral side portions only of the path of travel to establish a temperature gradient in the sheet moving between said directing means transverse to the path of travel;
• and
• means for moving a glass sheet along a path of travel through the furnace and said quenching station.