Pressurised mould filling system for feeding pre-expanded beads - e.g. of polystyrene, gives rapid, reproducible filling cycles

摘要

A pressurised pneumatic feed system is described for transferring pre-expanded thermoplastic (polystyrene) beads into one or more mould cavities in a closed tool. The beads are transferred by compressed air injection into a chamber isolated by a coarse valve from a gravity feed hopper and connected to a mould entry passage by one or more flexible pressure hoses. The pressure jet feed is more rapid and more reproducible than gravity or manual charging.