method and device for tauchbeschichten an object by wirbelsintern

摘要

PICT:0852638/III/1 Pre-heated articles are dip-coated by immersing them in a fluidized mass of powdered thermoplastic material having a melting point below the temperature to which the articles are heated, the material being fluidized by a gas which flows thereinto in a direction which is changed from instant to instant, whereby the tendency of the gas to flow in relatively few discrete paths through the material is substantially avoided. The powdered material e.g. polyethylene may be contained in an upper compartment 1 which is separated from a lower compartment 2 by porous tiles 3, or other suitable porous material, compressed air being supplied through a pipe 5 and passing through the tiles 3 to maintain the powder in suspension. Paddles 6 are reciprocated across the gas stream by means of a link 7, slide 8, connecting rod 9 and crank 10, which is driven by an electric motor; or a pneumatic device coupled to the fluidizing gas supply, may be used. The paddles, which may be plain, corrugated or perforated, may be arranged in tiers which may be reciprocated or given a rotary movement in the same or different directions. A honeycomb structure may replace the paddles. Alternatively, the container may be rocked about a vertical axis, the body of the fluidized mass remaining approximately stationary. The method may be operated continuously for dip-coating articles in succession and for treating elongated articles. p Reference has been directed by the Comptroller to Specification 759,214.