| 摘要 |
This invention relates to a process and a device for producing an even and homogeneous coating of liquids or powders on small free-falling objects that are not earthed. The process and the device according to the invention are primarily intended for surface coating of medicinal products and foodstuffs. According to the invention, the non-earthed objects are positively or negatively charged in a suitable manner or not at all and are then caused to fall freely and individually through a substantially cylindrically-shaped zone (2), mainly along its central axis, where the coating substance, having first, in a suitably manner, been charged with a charge of opposite polarity to that of the objects or if these are not charged, with a positive or negative charge, is sprayed onto the particles by means of at least one or preferably at least two spray nozzles (3) which are placed peripherally around the zone (2) and directed mainly towards the central axis thereof, whereby the coating substance is attracted to the object because of the potential difference between them, and an even, homogeneous surfrace coating is obtained. |
