Electrostatic powder coating
OwnerYashwant G. Ghaisasinventor
Life of this patent
Estimating the term…
Abstract
Electrostatic powder coating apparatus comprising a spray module located within a bight of a conveyor having suspended from it a plurality of articles to be coated with powder prior to heat treatment to convert the powder into an adherent coat of paint or the like. The spray module comprises a veined impeller able to rotate about a vertical axis and having charged powder projected towards its center from a stationary nozzle so that vanes on the impeller impart centrifugal force to the powder particles. The impeller and nozzle assembly may be reciprocated vertically so that the sprayed powder traverses the length of the suspended and moving articles.
Claims8
Apparatus for electrostatic powder coating, comprising a powder-spray module having (1) a substantially-vertical rotary shaft carrying an impeller at a lower end of said shaft, (2) a vertically movable sleeve surrounding in spaced relationship said rotary shaft and providing an air passageway in communication with said impeller, and (3) a non-rotatable nozzle assembly supported by the module and constructed and arranged to provide and transport a stream of electrostatically-charged powder downwardly to the center of the impeller;
- wherein the impeller comprises two parts, a lower part having an upwardly-facing concave inner surface, and an upper part having a downwardly-facing convex surface, and a plurality of substantially-vertical fins which are integral with either the upper part or the lower part, and the other part not integral with the fins is in contact with the fins in a manner so as to define therewith a plurality of upwardly-inclined powder-discharge passages;
- wherein air provided through said air passageway and centrifugal force provided by said impeller move said electrostatically-charged powder from said impeller to an article to be coated.
Dependencies are inferred from the claim text.