Device for pressing heterogeneous mixtures with regulated pressing force for separating liquid and solid fractions thereof, in particular fruit juices

An apparatus for pressing a heterogenous mixture for separating therefrom solid and liquid fractions intimately associated therein, comprising;

• a longitudinal vessel having side walls pierced with a plurality of fine openings for passing liquid therethrough, said vessel having opposite open ends, one end of said vessel being an upstream inlet end and provided with an opening for admission into said vessel of a heterogenous mixture of intimately associated solid and liquid fractions, the other end of said vessel being an open downstream outlet end for the evacuation of solid fractions from said vessel;
• a piston means situated at the upstream inlet end opening of the vessel and coaxially with respect to a longitudinal axis of said vessel, for imparting axial pressing forces upon said heterogenous mixture in said vessel;
• and
• central conical shield means accommodated coaxially in the downstream outlet end opening of the vessel, for receiving and reacting thrust forces acting upon said heterogenous mixture in said vessel and, in conjunction with said vessel, for providing an annular discharge passage around said shield means at said downstream outlet end opening for evacuation of said solid fractions therethrough;
• said piston means, said shield and said vessel being mounted for relative movement between said piston means and said shield and vessel for pressing the liquid and solid fractions in said heterogenous mixture between the shield and the piston means for forcing the liquid fractions of said mixture to pass through the vessel side walls via the fine openings therethrough and for forcing the solid fractions of said mixture to be discharged around said shield means through said annular discharge passage.