Method and System for an Improved Voltage Block

摘要

A method and system for supplying electrically conductive coating materials to an electrostatic dispenser (12) with a parallel arrangement of subsystems selectably coupled to the dispenser (12) by a four-port system voltage blocking valve (VBV1) which electrically isolates the subsystems. The subsystems each include first and second piston cylinders (24, 34) that alternatingly receive a selected coating material from a corresponding manifold and supply the coating material to the dispenser by a subsystem voltage blocking valve (VBVA) which isolates the dispenser from the manifold (MA2, MB2), when coupled to the dispenser (12). The first and second piston cylinders (C1, C2) of each subsystem also alternatingly receive a solvent from the corresponding manifold and direct the solvent to a waste receptacle by a corresponding subsystem voltage blocking valve (VBVA) when the subsystem is not coupled to the dispenser (12). The solvent removes previously supplied coating material from the non-selected subsystem and readies the non-selected subsystem for supplying a next selected coating material to the dispenser (12).