DIE MOULD TO PRESS POWDER-BASED ITEMS WITH OUTER SURFACE OF COMPLEX SHAPE Russian patent published in 1994 - IPC

FIELD: die mould to press powder-based items with outer surface of complex shape. SUBSTANCE: on filling moulding cavity with powder opening is covered with split top die 1. On applying press forces top die pushes sliding ring 4 ahead of it and powder enters top die cavity. Top die split parts enter stationary ring 3 which prevents expansion of wedges. First, powder is compacted under floating pressure of punch 8 and partially flows into spherical cavity of the top die. Powder being compacted is entrained by friction forces under action of sliding ring 4 into space between the ring and rod 7. Floating punch 8 comes down under elastic forces being subjected to counterforces from lower spring element 10. Top die 12 expels sliding ring 4 beyond moulding cavity by the end of pressing. The punch squeezes powder finally into the item of desired shape. Die-mould is applied for pressing items of changeable shape along height and curve surfaces. EFFECT: production of items of complex outer surfaces. 1 dwg