Continuous powder feed system for maintaining a uniform powder coating thickness on objects being coated by electrostatic fluidized beds

摘要

A continuous powder feed system for maintaining an essentially uniform powder cloud above an electrostatic fluidized bed coating unit is disclosed. The continuous powder feed system comprises a powder container and discharger for continuously feeding essentially non agglomerated powder into the coating bed of the electrostatic fluidized bed coating unit, powder retaining walls for containing the bed of such coating unit during fluidization, at least one powder retaining wall having a height such as to determine the powder level in the coating bed and permit overflow of excess powder from the coating bed, and a powder collection system for retrieving the overflowing powder from the coating bed.