Juice extraction press with concentric pistons esp. for grapes

摘要

Press comprises: (a) drainage system consisting of a normally cylindrical grill limiting the usable vol. of the pressure chamber, filling port and discharge port; (b) pressure system consisting of a normally cylindrical piston occupying the entire cross section of the pressure chamber; and (c) retention system consisting of an adjustable door at the level of the discharge port, capable of controlling extraction pressure. The pressure system consists of at least two sections, one cylindrical (4) and one annular (5), whose total cross section occupies the total cross section of the pressure chamber (8) and which are capable of longitudinal displacement within the chamber, simultaneously or independently, in the same or opposite direction, dependant on the stage of the process.