COATING OF ARTICLES WITH OPTIONAL PULSING AND RECYCLE OF COATING MATERIAL

摘要

A powder coating apparatus capable of applying powder coating material into articles at high production rates while recovering oversprayed powder is provided. The apparatus may include a powder coating applicator that may form part of a circulation loop for powder coating material from a supply, through the applicator, and back to the supply. The powder coating apparatus may rapidly switch between applying powder coating material and circulating the powder coating back to the supply. In one embodiment, the applicator includes an inlet and a diverter having a first operating mode during which powder coating material flows from the inlet to a first coating material outlet for a coating operation, and a second operating mode during which powder coating material flows from the inlet to a second coating material outlet for a non-coating operation. The coating applicator may be reciprocated into and out of a container such as a tube, with powder sprayed by the applicator into the tube as the applicator is lanced into the tube, and with oversprayed powder which does not adhere to the interior of the tube being pulled back through the applicator as the applicator is withdrawn back out of the tube, for example. A densifier, or condensing device, may be used to remove air from the air entrained powder, and increase the powder to air ratio before the powder is sprayed from the applicator into the container.