Patent ID: 8453478

Claim:
A method for manufacturing a glass sheet, the method comprising: running down molten glass along both side surfaces of a molded body arranged inside a molding chamber; joining and integrating the molten glass just under a lower edge part of the molded body; and drawing downward an integrated sheet-shaped glass ribbon out of an opening of the molding chamber, wherein a viscosity ratio (V 2 /V 1 ) of a viscosity (V 1 ) of a center in a width direction of the molten glass in an upper edge of the molded body to a viscosity (V 2 ) of a center in a width direction of the glass ribbon passing through the opening of the molding chamber is set in the range of 20 to 50000, a thickness of the center in the width direction of the glass ribbon passing through the opening of the molding chamber is set to 1.0 mm or less, a gap between a vertical plane including a lower edge of the molded body and the opening of the molding chamber, in a direction orthogonal to the vertical plane, is set in the range of 8 mm to 70 mm, and gaps between side surface portions in a width direction side of the glass ribbon of the opening of the molding chamber and respective ends in the width direction of the glass ribbon passing through the opening of the molding chamber are set in the range of 10 mm to 500 mm, wherein the opening of the molding chamber is formed of a first opening member and the first opening member includes plural blocks for molding chamber divided in a width direction of the glass ribbon passing through the opening of the molding chamber, and a shape dimension of the opening of the molding chamber is adjusted or changed by moving the one or plural blocks for molding chamber in a direction of moving near to or away from the vertical plane or by replacing the one or plural blocks for molding chamber.