Moulding articles from pref. wood pulp material using mould - to which different suctions are applied to vary pulp density in different regions

摘要

A moulding device has pref. general moulding blocks mounted on a rotary support which rotates to immerse the blocks serially in a bath of pref. wood pulp. The moulding blocks are connected via valves and radial channels in the rotary support to a suction device whereby as the support rotates the valves are opened selectively to vary the suction applied to different regions of each moulding block when it is immersed in the pulp bath so that pulp is sucked onto the moulding block and different regions of the moulded pulp article formed on the moulding block have different densities or thicknesses. The device is partic. used for moulding egg boxes. Regions of inherent weakness of the moulded article can be strengthened by increasing the density or thickness.