METHOD OF AND APPARATUS FOR ELECTROSTATIC POWDER SPRAY COATING AND RESULTING COATED PRODUCT

摘要

An electrostatic powder spray coating method and apparatus for producing evenly coated continuous films of thermoplastic and thermosetting powders on substrates or parts having electrically conductive geometric complex surfaces, is described. The method and apparatus of this invention enables the use, without the occurrence of "cobwebbing," of significantly higher charging voltages for the spray gun in the spray coating of preheated substrates and parts, thus allowing faster coating lines. The invention features the use of a grounded electrically conductive ring for grounding the ionized field in the powder discharge region of the spray gun.