Apparatus for making miniature capsules

Abstract

Apparatus for making miniature capsules having a capsule-forming orifice defined by the open ends of two coaxial conduits. The inner conduit defines a central opening in the orifice and the outer conduit defines an annulus circumferentially of the central opening. Filter-content material for the individual capsules is extruded as a stream through the central opening and a settable coating liquid material is extruded as a thin film sleeve circumferentially of the filler-content material stream. The film sleeve and the stream of filler-content material pass through a cooling liquid which is flowed through a fixed nozzle downstream of the extruding orifice. The nozzle has an inlet section with converging inner surfaces and a uniform diameter downstream of the inlet section. The cooling fluid, the film sleeve and filler-content stream therein all pass through the nozzle. A driven annular vibrator is disposed within the nozzle and develops vibrations in the cooling fluid parallel to the direction of the path of travel of the flow to form discrete droplets of the filler-content material enclosed in a film of the settable material. The droplets are recovered as miniature capsules.