Machine for molding optical element

An optical element molding machine adapted for use with a molding block having upper and lower molding dies with a glass blank placed therebetween and a sleeve die supporting the upper and lower molding dies, comprising:

• a chamber having an inlet for loading the molding block thereinto, and an outlet for discharging the molding block therefrom;
• an inlet shutter for opening and closing said inlet;
• an outlet shutter for opening and closing said outlet;
• gas supply means for introducing nonoxidizing gas into said chamber;
• a plurality of lower heating plates mounted in said chamber;
• a plurality of upper heating plates mounted in said chamber opposite said plurality of lower heating plates, respectively, to form a plurality of heating plate pairs, one of said upper and lower heating plates of each of said heating plate pairs being movably mounted in said chamber for movement relative to the other of said upper and lower heating plates of each of said heating plates pairs, respectively;
• wherein each of said upper and lower heating plates has a molding block pressing portion for contacting a respective one of the upper and lower molding dies of the molding block;
• wherein heat insulating plate means are mounted on each of said plurality of upper and lower heating plates for covering substantially all surfaces of said upper and lower heating plates except for said molding block pressing portions thereof;
• wherein a heating zone is defined in said chamber by a first plurality of said heating plate pairs, a cooling zone is defined in said chamber by a second plurality of said heating plate pairs, and a deformation zone is defined in said chamber by at least one other of said heating plate pairs;
• and
• wherein a transport means is provided for sequentially moving the molding block through said heating zone, said deformation zone, and said cooling zone.