Abstract: The machine is designed particularly for molding plastics and includes two mold locking units, each having a stationary yoke and a mobile yoke, associated with a turntable used for transporting an open mold between first and second working stations. The turntable is mounted for rotation about an axis parallel to the direction of operation of the mold locking units and between the stationary and mobile yokes, to extend between the working stations. A rotary piston drive is mounted on a stationary yoke coaxially with the turntable axis to rotate the turntable. A spring is provided to exert a lifting effect on the turntable to provide a slight clearance between the turntable and the stationary yokes, and a hydraulic pressure mechanism acts coaxially of the turntable in opposition to the spring so that, when supplied with pressure, the turntable is forced against the lower or stationary yokes.