Patent ID: 6138477
Filing Date: 2000-10-31
Classification: C03B

Abstract:
Process for the convex bending of a glass plate heated to a convex bending temperature in a horizontal furnace which it traverses carried by a flat conveyor which passes it into a convex bending cell where there is an ambient temperature substantially identical to the convex bending temperature and in which there is provided a convex, solid, male mold in a direction of which the glass plate is moved vertically by an annular, concave, female countermold, in order to be pressed, in a pressing phase, between the male mold and the female countermold, comprising the steps of:preheating the horizontal furnace to the convex bending temperature;placing a glass plate for forming by gravity on the female countermold before the glass plate comes into contact with the male mold, wherein the glass plate is a stack composed of two glass sheets which are superimposed on entering the horizontal furnace;keeping the glass plate in contact with the male mold following the pressing phase;obtaining suction by a vacuum created only in a vicinity of a periphery of the male mold; andproducing glazings locally having a nondevelopability criterion exceeding five.