Molding flask for a molding machine and a molding process using the molding flask

A method for molding using a flask unit to be incorporated in a flaskless molding machine that has a pair of pressing members for pressing molding sand, wherein the flask unit is adapted to be the flaskless molding machine for simultaneously making an upper mold and a lower mold, wherein said flask unit has two flasks for holding said molds, respectively, such that said flasks are turnable in the vertical plane while each flask approaches, and retreats from, the other one, each flask comprising a body that defines an opening in which a sand mold is to be molded and each having an inlet for introducing said molding sand into said opening, two mounting members, each integrally provided on opposite sides of each body of each flask for mounting said flasks on a pair of connecting arms that integrally connect one flask to another flask to form said flask unit so that the one flask and the other flask can be moved between a position where they are opposed to, and a position spaced apart from, each other by sliding the mounting members of each body of each flask along the connecting arms, while the bodies are supported at both their opposite sides by said connecting arms, wherein said connecting arms are arranged on a centerline of said opposite sides of said bodies of said flasks such that the connecting arms are opposed to each other, and

• wherein each body or each mounting member of each flask has an engaging member for engaging an actuator outside of said flask such that a force or forces from said actuator can be transmitted to said flask, said method comprising the steps of:
• moving the flasks of the flask unit toward each other from the spaced apart position to the opposed position by sliding said opposed mounting members of the body of each flask along said connecting rods of the flask unit;
• defining a pair of molding spaces by inserting each pressing member into each opening of the body of said two flasks of said flask unit;
• introducing molding sand into said pair of molding spaces through said inlets of said bodies;
• moving said flask unit back and forth between a position where said defining step is carried out and a position where said introducing step is carried out;
• and
• molding a half-mold in each flask of said flask unit to form a pair of half-molds by pressing said introduced molding sand with said pressing members,
• wherein said molding step is carried out while said flask unit is being moved back to said defining step position.