Method for increasing the injection speed of a plastic injection device

Abstract

A method for increasing the injection speed of a melted plastic injection device for injecting said melted plastic into a molding cavity (51), said injection device comprising a first cylinder (1) provided with a tubular casing (2) defining a first inner diameter d1, and a first piston (3) slidable inside said tubular casing (2), adapted to be loaded with melted plastic and to inject said melted plastic toward the molding cavity (51); a second cylinder (21) constrained to the first cylinder (1) and provided with a second piston (23) which rod (24) is connected to the first piston (3) and is adapted to actuate said first cylinder (1) during an injection operation; the method comprising the steps of: —releasing second cylinder (21) and first cylinder (1) by extracting the first piston (3) from the tubular casing (2); —coaxially inserting a tubular body (12), defining a second inner diameter d3 which is smaller than the first inner diameter d1, into the tubular casing (2); —disconnecting the first piston (3) from the rod (24); —connecting a third piston (13) to the rod (24), said third piston (13) being sized to slide inside said tubular body (12); —constraining second cylinder (21) and first cylinder (1) by inserting the third piston (13) into the tubular casing (2).

Dependencies are inferred from the claim text.