Vacuum moulding and trimming appts - the mould carrying the article being pushed into a cutting die

摘要

Appts. for thermoforming hollow plastics articles includes a relatively reciprocable mould passing through a cutting die, the edges of which shear the flash projecting beyond the mould. Pref. the sheet to be formed is heated on an apertured plate interposed between the mould and die and blown into the mould by air passing through the apertures in the plate. The plate is withdrawn and the mould and die moved into contact to effect trimming. The article is ejected from the mould into a take-off chute. Such a trimming arrangement is comparatively simple and cheap and enables automatic stacking to be effected. In several embodiments >1 mould/die combination and/or >1 heating plate is used to increase output. In one embodiment a rotating take-off device takes articles alternately from two moulds first to one stacking chute and then, when that chute is full to a second chute.