Patent ID: 8413707
Filing Date: 2013-04-09
Classification: B22C

Abstract:
1. A molding process for simultaneously making an upper mold and a lower mold, the process comprising the steps of: defining a lower molding space by a drag flask that can enter or leave a molding space in which molds are made, a match plate having patterns on upper and lower surfaces and mounted on an upper surface of the drag flask, a lower filling frame provided with a molding-sand introducing port on a surface of a sidewall thereof and being connectable to a lower end of the drag flask to allow the lower filling frame to ascend and descend, and an ascendable and descendable lower squeeze board, and defining an upper molding space by a cope flask provided with a molding-sand introducing port on a surface of a sidewall thereof and being mountable on the match plate to allow the cope flask to ascend or descend, and an upper squeeze board that is opposed to and fixedly provided above the match plate; simultaneously introducing molding sand into the upper molding space and the lower molding space; squeezing the molding sand in the upper and lower molding spaces by raising the lower squeeze board to simultaneously make an upper mold and a lower mold in said spaces; drawing the upper mold from the pattern on the upper surface of the match plate, while drawing the lower mold from the pattern on the lower surface of the match plate; and stripping the upper mold from the cope flask, while stripping the lower filling frame from the lower mold wherein the lower filling frame, the lower squeeze board, and a tower squeeze frame constitute a lower squeeze unit, in which the lower filling frame is ascendable and descendable independently of and simultaneously with the lower squeeze board, the lower squeeze frame is ascendably and descendably mounted on at least two columns, and wherein a plurality of cylinders of the lower filling frame are mounted on the lower squeeze frame in an upward direction such that leading ends of piston rods of the cylinders of the lower filling frame are attached to the lower filling frame, and wherein the lower squeeze unit is being defined while the lower squeeze unit ascends in unison or at an ascending end.