Abstract: An electrostatic powder coating unit utilizes a tubular cloud of charged particles moving helically within a generally cylindrical porous member, for coating workpieces conveyed therethrough. The electrode assembly, by which ionized air is produced for charging the particles, may be mounted to rotate about the cylindrical porous member, for optimal efficiency and effectiveness.

Abstract: An electrostatic fluidized bed coating method, apparatus and system utilize a vortex effect within the particle cloud to produce coatings of exceptional uniformity upon a workpiece. The vortex effect produces a secondary particle cloud and a secondary electrostatic field, which contribute to the uniformity of the deposit, and the amount of metal structure included in the unit may be minimized, also to enhance uniformity. Operation can be carried out at voltages that are significantly reduced from those required for similar systems known in the art.