Abstract: An electrostatic coating apparatus is described comprising an applicator, means for supplying liquid to the applicator at a controlled rate, means for establishing an electrostatic field between the applicator and a target substrate to be coated and control means providing an output signal to the liquid supply means for setting the rate at which liquid is supplied to the applicator, the said control means also providing an output signal to the field establishing means which, in operation, sets the magnitude of the applied field, the said output signals being such that the applied field is varied in accordance with any change in the rate of supply of liquid to the applicator.

Abstract: A rotary atomizer for coating workpieces with a fine layer of liquid material, and a method of operating the said atomizer.A rotary atomizer (10) for coating workpieces with a fine layer of liquid material fed at very low flow rates includes a bell-type rotatable atomizing device (12) for dispensing the liquid from an edge (17) in an atomized condition under the effect of centripetal forces. The liquid fed into a tube (21) having an outlet (20) within the bell (12) appears as discontinuous drops (40) at the outlet (20). Air is also fed into the bell (12) via a tub (25) having an outlet (26) disposed adjacent the liquid outlet (20) such that the air jet (41) breaks up the drops (40) and forms a spray (42) directed at the internal wall of the bell (12). The spray (42) coalesces into a continuous film of liquid as it travels on the internal wall of the bell (12) to the discharge edge (17).