VALVE-GATED HOT RUNNER SYSTEM HAVING REDUCED VALVE-STEM DROOL

摘要

Disclosed is a valve-gated hot-runner system (100; 200; 300; 400), having: (i) a back-up sealing arrangement (117), including: (i) a plurality of radial gaps (116A; 116B; 116C) associated with a valve stem (106) of a valve actuator (108), and (ii) a cooling system (114) being positioned relative to the plurality of radial gaps (116A; 116B; 116C), the cooling system (114) being configured to freeze a drool (109) being made to enter, under pressure, into the plurality of radial gaps (116A; 116B; 116C), so that the drool (109) that becomes frozen substantially reduces flow of the drool (109) along the valve stem (106) and toward the valve actuator (108).