An electrostatic paint atomizer connected to a discharge station at high voltage is supplied, via an isolating conveying line, with individual divided-off quantities of paint enclosed between two pigs from a loading station at the other end of the conveying line. The paint is conveyed by a transport device supplying a thrust medium (compressed air or insulating liquid) to discharge the paint in the discharge station. A reverse transport device operating with compressed air transports the pigs back to the loading station. The length (L) of the conveying line between the loading and the discharge stations and the length (l) of a divided-off quantity of paint, are dimensioned to provide a sufficiently long isolating path (L-l) to avoid a voltage flashover. A continuous supply of paint is achieved with two parallel conveying lines, through which quantities of paint are metered with an offset from each other.

The paint-spraying apparatus exhibits a supply line 7 for coating material, extending from the color changer to the atomizer. Cut-off valves 26, 27 installed in the supply line delimit an insulating section 25 of said supply line, which insulating section is associated with means 28 to 32 for emptying and flushing said insulating section 25. A voltage divider 16 is connected in parallel to said insulating section 25. When colors are changed, the residual coating material present in said voltage divider 16 can be moved into the empty insulating section 25, after which it is forced by means of slugs back through the entire supply line 7 to the color changer 1, and is thus reclaimed.