Abstract: An electrostatic spraying apparatus for spraying liquid has a spraying edge 8 provided with teeth 12. No parts of the apparatus provide a low potential influence near the spraying edge, keeping leakage losses to a minimum. At the voltage provided by a high voltage supply, the field strength at the tips of the teeth 12, is sufficient to form one ligament of liquid per tooth. The ligaments break up into droplets which have a size largely independent of fluctuations in field strength caused by varying the distance from the target to be sprayed.

Abstract: A sprayer, particularly for use in agricultural crop-spraying, has a rotary atomizer comprising a rotary frusto-conical part, a slotted cylindrical liquid distribution member fixed centrally in the rotary part, and a liquid distributor of frusto-conical form but inverted relative to the rotary part. The distributor is fixed to the slotted liquid distribution member, surrounding and substantially enclosing it. The rotary part is arranged to rotate in bearings in a bearing housing in a fixed part of the sprayer and a stationary liquid feed tube supplies liquid to the member. The interior surface of the distributor is smooth and the interior surface of the rotary part is grooved. In use, the rotary part is caused to rotate by the rotation of a turbine and liquid supplied to the member is ejected by centrifugal force through the slots onto the smooth interior surface of the distributor at or near the smaller diameter portion thereof.

Abstract: A rotary atomizer suitable for spraying crops with liquid in the shape of a hollow truncated cone having a toothed periphery and internal radial grooves has asymmetric teeth, one side of each tooth being radial and the other side of each tooth being disposed at an angle, preferably 30.degree.-60.degree. to the radius. The grooves lead to the gaps between teeth and may be similarly assymmetrical.The atomizer is unidirectional being rotated so that the radial teeth edges are the leading edges. It may be used singly, or as a stack of cones.

Abstract: A rotary atomizer suitable for spraying crops with liquid is driven by the liquid itself. The atomizer comprises a hollow, truncated cone, a central axial shaft extending through the interior of the cone, a liquid jet driven turbine on the shaft, and an opening in the turbine so that liquid flows from the turbine to the interior of the cone.The liquid may be used at pressure of 0.7 to 10 bars gauge and feed rates of 10 to 1,000 ml/min, with the rate of feed being equal to the rate of discharge so that there is no liquid recycle.

Abstract: A rotary atomizer suitable for spraying crops with liquid comprising a stack of hollow truncated cones with internal grooves spaced apart by ribs mating with some of the grooves and held together on a central, stationary spindle by thrust bearings at either end.The central spindle may be hollow with holes from the interior to the exterior for feeding liquid to the cones.