Plastics injection-moulding device with injection-moulding machine and injection mould

摘要

Such a device exists in which a runner (17) in the injection mould (2) opens out via a constantly open aperture (18) into a mould cavity (24) and a shut-off device is provided in order optionally to permit the passage of the material to be injected under pressure through the aperture or to prevent the passage of the material to be injected. It is desirable here if virtually sprue-less mouldings can be produced with improved handling of the liquid material to be injected. This is achieved by forming the shut-off by adhesion of the material to be injected in the runner (17) with the pressure shut off. Use is made of the fact that a liquid does not emerge from an open end of a runner if the viscosity of the liquid, shape of the runner and pressure conditions are matched to one another. Because of the adhesion shut-off, the runner is constantly open as far as the aperture, that is to say never blocked by means of slides or hardened material and the material to be injected is never sucked back and accelerated. <IMAGE>