Coating method for small items containing recesses

摘要

The items are delivered into a drum rotating slowly to apply the coating, after which centrifugal force is used to remove surplus coating material. The drum is of spiral cross-section, and after receiving the items it is rotated at a constant slow speed on a horizontal axis in a first direction in which the radius vector of the spiral curve increases, while at the same time it is at least partly immersed in a bath (46) of coating material. The drum (27) is then lifted out of the bath and rotated slowly in the opposite direction, so that the items drop out of its inlet opening (26) and into a centrifugal drum open at the top and rotating at high speed on a vertical axis.