FLASKLESS MOLDING MACHINE

A flaskless molding machine 1 includes: an upper flask 15 and a lower flask 17 capable of clamping a match plate; a drive unit (37) moving the lower flask in a vertical direction; a lower filling frame 41 capable of communicating with the lower flask; an upper plate 25 capable of entering and being retracted from the upper flask; a lower plate 40 capable of entering and being retracted from the lower filling frame; an upper flask oil-hydraulic cylinder (16) coupled to the upper flask; a first oil-hydraulic circuit (81) of the upper flask oil-hydraulic cylinder; a lower filling frame oil-hydraulic cylinder (42) coupled to the lower filling frame; a second oil-hydraulic circuit (83) of the lower filling frame oil-hydraulic cylinder; and drive units (37, 80) performing a squeeze process by moving the lower plate in an upward direction. The first oil-hydraulic circuit includes a back pressure circuit (82) applying, to the upper flask oil-hydraulic cylinder, a first back pressure serving as a resistance against an upward movement of the upper flask toward the upper plate during the squeeze process. The second oil-hydraulic circuit includes a back pressure circuit (84) applying, to the lower filling frame oil-hydraulic cylinder, a second back pressure serving as a resistance against a downward movement of the lower filling frame toward the lower plate during the squeeze process.