Float-bath ribbon-width control method and system
AssigneeNippon Sheet Glass Co., Ltd.
InventorsMasaharu Okafuji, Junichi Noguchi, Tomizo Otsuki
Life of this patent
Estimating the term…
Abstract
The width of glass ribbon at the hot end of a float bath is controlled to a constant value by raising and lowering a tweel for adjusting the flow of molten glass blank from a smelting furnace to the float bath. The controlled value of the tweel is obtained from predetermined control variables through fuzzy inference. This method is carried out in a float-bath ribbon-width control system using a fuzzy inference means that obtains the controlled value of the tweel from predetermined control variables through fuzzy inference.
Claims8
In a glass manufacturing system in which molten glass, having a temperature, flows from a canal into a float bath, said float bath having first and second sides, at a rate determined by a tweel, to produce a ribbon of molten glass, which ribbon has first and second edges that define a width, a method for controlling the width of the glass ribbon in the float bath to maintain the width of the ribbon at a substantially constant value by raising and lowering the tweel to adjust the flow of the molten glass into said float bath, characterized in that the tweel is controlled through fuzzy inference using predetermined control variables including:
- deviation of the first edge of the ribbon from a first desired position relative to the first side of the float bath,
- deviation of the second edge of the ribbon from a second desired position relative to the second side of the float bath, and
- the temperature of the molten glass in the canal.
In a glass manufacturing system in which molten glass, having a temperature, flows from a canal into a float bath, said float bath having first and second sides, at a rate determined by a tweel, to produce a ribbon of molten glass, which ribbon has first and second edges that define a width, apparatus for controlling the width of the glass ribbon in the float bath to maintain the width of the ribbon at a substantially constant value by raising and lowering the tweel to adjust the flow of the molten glass into said float bath, the apparatus comprising:
- means for providing a measure of deviation of the first edge of the ribbon from a first desired position relative to the first side of the float bath as a first predetermined control variable,
- means for providing a measure of deviation of the second edge of the ribbon from a second desired position relative to the second side of the float bath as a second predetermined control variable,
- means for providing a measure of the temperature of the molten glass in the canal as a third predetermined control variable, and
- control means, including fuzzy inference means, which is responsive to the first, second and third predetermined control variables for determining when the tweel is to be raised or lowered.
Dependencies are inferred from the claim text.