Device and method for the suction of air in injection molds and the subsequent expulsion of molded pieces

A device for the suction of air in injection molds and the subsequent expulsion of molded pieces, comprising

• a Venturi ejector,
• a first valve connected to the Venturi ejector configured to suction air in a mold cavity when the mold is closed thereby initiating an injection cycle,
• a pneumatic double-effect piston in fluid communication with the Venturi ejector and configured to close passage of air in a direction of the Venturi ejector when the first valve is closed;
• at least one insert made from porous material through which and by means of a communication duct defines a suction circuit, said at least one insert is in fluid communication with the pneumatic double-effect piston;
• and
• a second valve in fluid communication with the pneumatic double-effect piston, actuating the pneumatic double-effect piston to blow air towards the at least one insert after the solidification of the plastic material, thereby cleaning said at least one insert made of porous material,
• wherein upon ending the injection cycle, the first valve that causes the suction of air closes, and
• wherein upon expulsion of the mold, the second valve enters into operation by making the double-effect piston actuate, closing a passage in a direction of the Venturi ejector, concentrating a pressure only on cleaning the porous material.