Molding machine

A molding machine comprising:

• an injection container unit configured to store a foamed mixed material;
• a lid member configured to open and close an opening at a top of the injection container unit;
• and
• an air supplying section configured to supply air into the injection container unit to thereby eject the foamed mixed material through an ejection port in the injection container unit,
• the lid member having a circumferential surface on which a sealing body is provided, the sealing body being configured to (i) inflate when supplied with a fluid and thereby make close contact with an inner circumferential surface of the injection container unit and (ii) deflate when the fluid stops being supplied while the sealing body having inflated due to supply of the fluid is in close contact with the inner circumferential surface, and thereby break the close contact and detach from the inner circumferential surface of the injection container unit,
• supply of the fluid to the sealing body being stopped while the lid member is being moved in a case of closure, by the lid member, of the opening of the injection container unit and in a case of removal, from the opening, of the lid member having closed the opening of the injection container, the lid member and the sealing body moving without sliding on the inner circumferential surface of the injection container unit in the closure and in the removal,
• the lid member including an upper partial member and a lower partial member,
• the lower partial member having a surface facing toward an inside of the injection container,
• the upper partial member having a first recess in a first surface of the upper partial member, the lower partial member having a second recess in a second surface of the lower partial member, the first surface and the second surface facing each other, the first recess and the second recess joining together to form a recess on the circumferential surface of the lid member,
• the sealing body including (i) a sealing portion which, in cross-section, is convex toward the inner circumferential surface of the injection container unit, the sealing portion being exposed on the circumferential surface of the lid member, and (ii) mounting portions located at opposite edges of the sealing portion, the mounting portions abutting on the recess.