| 摘要 |
PCT No. PCT/US93/12391 Sec. 371 Date Jun. 7, 1995 Sec. 102(e) Date Jun. 7, 1995 PCT Filed Dec. 16, 1993 PCT Pub. No. WO94/13405 PCT Pub. Date Jun. 23, 1994A powder coating system for difficult to handle powders includes a powder hopper containing fluidized powder particles, a pump body connected to the hopper and having an inlet in communication with the hopper, an ejector nozzle mounted to the pump body and aimed at an outlet thereof, a second nozzle mounted to the pump body and aimed at the inlet thereof and a powder application device for receiving powder particles from the outlet of the pump body and spraying them onto an article to be coated. The ejector nozzle sprays pressurized air toward the outlet to transport powder particles along a flow path which extends from the powder hopper into the pump body via the inlet and then out of the pump body via the outlet. The second nozzle sprays air pulses at the inlet in a direction opposite the particle flow along the flow path caused by the ejector nozzle. This spray from the second nozzle creates microvibrations in the inlet of the pump body to eliminate powder particle adherence and cohesion thereat. The pump body may have separate, spaced intake and ejector portions, with the ejector nozzle mounted in the ejection portion and the second nozzle mounted on the intake portion.
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