Patent ID: 6299690
Filing Date: 2001-10-09
Classification: B22F,B30B

Abstract:
Apparatus for lubricating a wall surface of a die cavity in which a powder will be compacted to form a three-dimensional article and from which the article will be ejected, the die cavity having walls defining the shape of the article, said apparatus comprising: a plug member having a three-dimensional shape generally conforming to that of said article, said plug member being insertable into said die cavity with a narrow gap between the walls of said cavity and adjacent outer wall surfaces of said plug member; a closing plate to which said plug member is secured; means for moving said plug member into said cavity and outwardly therefrom, said closing plate closing said die cavity when said plug member is within said die cavity; a plurality of tubes spaced apart adjacent the periphery of said plug member, extending therethrough and exiting at one or more of said outer wall surfaces of said plug member; means for supplying tribocharged particles of a lubricant material to said tubes using a pressurized inert gas; and venting means in said plate; whereby lubricant material is fed under pressure to said tubes and into said gap when said plug member is within said die cavity so that the lubricant material is electrostatically attracted to all wall surfaces of said cavity and excess gas and lubricant is vented from said gap via said venting means.