Polystyrene moulding gas pressure regulator - esp. for adjusting press. to foaming pressure, used in mfr. of foam mouldings from expansible polystyrene beads

摘要

Gas-press. regulating device, used partic. in mfr. of polystyrene mouldings in double-walled moulds includes a pneumatic feed increaser (sic) with 2-membranes which are arranged inside the feed increaser and controlled via a duct and a spring loaded double cone. The membranes are connected by an element provided with holes. An axially mobile plunger acts upon the element and carries, at its end nearest the mould, =1 devices associated with the perforated inner wall of or outer wall of the mould. A line connects the mould with the feed increaser. Continuous monitoring of the foaming press. is possible during the cooling of the moulding until it is ejected from the mould. Direct heat transfer from the hot mould wall to the plastics foam is minimised. This reduces risk of surface flaws and gives prods. with uniform apparent density.