GB916837A - Improvements in or relating to apparatus for forming multilayer molded pulp articles - Google Patents

Abstract

916,837. Moulding laminated pulp. DIAMOND NATIONAL CORPORATION. July 11, 1961, No. 25119/61. Class 87(2). In a process for moulding laminated pulp articles, separate slurries of pulp are caused to successively immerse a moulding screen in sealed chambers of variable volume. A plurality of moulding screens 12 each surrounded by side plates 13 and divider plates 14 are carried around the periphery of a revolving drum 10. Each screen 12 is in turn immersed by slurry in tanks 16 and 18, of flexible wall construction, by raising the level of slurry by diminishing the tank volume upon pressing between fixed abutment plate 32 and movable plate 34, operated by piston rod 36 of jack 38. A seal is effected during immersion by inflating elements 44 and a vacuum is applied to screens 12 to result in adherence thereto of a layer of pulp. After immersion jack 38 is retracted and seals 44 deflated and the level of pulp in the tanks replenished by suitable means e.g. a float valve. The drum 10 is revolved one step to place the screen previously immersed in tank 18 over receptacle 40 where slight drying occurs, and thence similarly immersed in the slurry of tank 16. In further embodiments immersion is obtained by air pressure over one arm of a U-shaped tank of rigid construction, Fig. 4 (not shown) or by air pressure acting directly upon the flexible walls of a tank, Fig. 5 (not shown).