METHOD FOR PRESSING POWDER MATERIALS AND APPARATUS FOR PERFORMING THE SAME Russian patent published in 2007 - IPC B22F3/02 B22F3/03 B30B15/02 

FIELD: manufacture of optical parts by pressing different type powder materials.

SUBSTANCE: surfaces of part parallel to pressing axis are formed by means of shaping surfaces of closed press-mold members made in the form of built-up die and two punches. Shaping members divided by portions along pressing axis may move one relative to other and normally relative to pressing axis. Process is realized at three stages in such a way that near-wall friction forces acting along shaped surface at first stage are directed opposite relative to acting pressing effort; at second stage resulting force is equal to zero and at third stage force acts in accordance with acting pressing effort. Calibrated springs are mounted along axis of stop secured to casing of press-mold at side of upper end for engaging with lower punch, between built-up portions of die and on upper end of stop and also at inner side of casing for engaging with lower portion of built-up die.

EFFECT: possibility for making parts with optically smooth surfaces corresponding to desired characteristics of refraction and absorption, small cost price of manufacturing process.

2 cl, 1 dwg, 1 tbl