Die and punch assembly for compacting powder material

A unitary punch and die assembly for mounting on a powder compacting press, said assembly comprising a die plate, a pocket in said die plate a removable die bushing disposed in said pocket, at least one guidepost supported by said die plate and extending substantially parallel to the axis of said assembly, a pair of spaced apart plates slidably reciprocable in unison relative to said die plate and being supported and guided by said guidepost, a recess in one of said plates most proximate to said die plate, a punch member normally slidably engaged in a die bore in said die bushing and having an enlarged foot portion in said recess in said plate, means for clamping said punch on said plate, coupling means disposed below the other of said plates for connection to an actuating member dependent from said press, linking means interconnecting said plates for reciprocating said plates in unison, and a die bushing retainer in the form of a cylindrical member provided with a peripheral thread engageable with an internal thread formed in the pocket in said die plate, said thread being of an assymetrical shape with the driving side of said thread forming an acute angle with a plane perpendicular to the axis of said thread.