Atomization of liquids

Claim 2

A spraying apparatus for spraying a liquid onto a plant comprising at least two spraying devices mounted on a boom each such spraying device comprising: a spray-head having an at least electrically semi-conducting surface; means for electrically charging the spray-head surface to a potential of the order of 1-20 kilovolts; means for delivering spray liquid to the surface; a field intensifying electrode mounted adjacent to the spray-head surface; and means for connecting the field intensifying electrode to earth; the electrode being so sited relative to the spray-head surface that when the spray-head surface is charged, the electrostatic field thereat causes liquid thereon to atomise without substantial corona discharge to form electrically charged particles which are projected past the electrode and into contact with the plant.

Claim 3

A tractor attachment for atomising liquid pesticide to form charged atomised spray particles and to project them along trajectories determined primarily by electrostatic forces to contact plants growing in the earth, said attachment comprising: a boom attachable to a tractor; sprayheads mounted on said boom each having an at least semi-conducting external surface defining a spray orifice; means for electrically charging each sprayhead surface to a potential of the order of 20 kilovolts; means to flow liquid to and through each orifice under gentle hydrostatic pressure; a field-intensifying electrode mounted adjacent to each orifice and aside from and asymmetrically with respect to each said trajectory; and means for electrically connecting said field-intensifying electrode to the earth in which the electrode being so sited relative to the surface that when the surface is charged by the charging means the electrostatic field thereat is sufficient without substantial corona discharge to draw the liquid out into a regular pattern of ligaments, which ligaments break up into a cloud of charged atomised spray particles which follow said trajectories to the plants so that the cloud wraps around the leaves of the plants and coats both the upper and lower surfaces of the leaves.

Claim 4

A tractor attachment for atomising liquid pesticide to form charged atomised spray particles and to project them along trajectories determined primarily by electrostatic forces to contact plants growing in the earth, said attachment comprising: a boom attachable to a tractor; sprayheads mounted on said boom each having an at least semi-conducting external surface defining a spray orifice; means for electrically charging each sprayhead surface to a potential of the order of 20 kilovolts; means to flow liquid to and through each orifice under gentle hydrostatic pressure; a field-intensifying electrode mounted adjacent to each orifice and aside from and asymmetrically with respect to each said trajectory; and means for electrically connecting said field-intensifying electrode to the earth in which the electrode being so sited relative to the surface that when the surface is charged by the charging means the electrostatic field thereat is sufficient without substantial corona discharge to draw the liquid out into a regular pattern of ligaments, which ligaments break up into a cloud of charged atomised spray particles which follow said trajectories to the plants so that the cloud wraps around the leaves of the plants and coats both the upper and lower surfaces of the leaves.

Claim 5

In combination with a powered vehicle a boom mounted on the vehicle and at least two spraying devices mounted on the boom for spraying a liquid onto a plant, each such spraying device comprising: a spray-head having an at least electrically semi-conducting surface; means for electrically charging the spray-head surface to a potential of the order of 1-20 kilovolts; means for delivering spray liquid to the surface; a field intensifying electrode mounted adjacent to the spray-head surface; and means for connecting the field intensifying electrode to earth; the electrode being so sited relative to the spray-head surface that when the spray-head surface is charged, the electrostatic field thereat causes liquid thereon to atomise without substantial corona discharge to form electrically charged particles which are projected past the electrode and into contact with the plant.

Claim 6

In combination with a powered vehicle a boom mounted on the vehicle and at least two spraying devices mounted on the boom for spraying a liquid onto a plant, each such spraying device comprising: a spray-head having an at least electrically semi-conducting surface; means for electrically charging the spray-head surface to a potential of the order of 1-20 kilovolts; means for delivering spray liquid to the surface; a field intensifying electrode mounted adjacent to the spray-head surface; and means for connecting the field intensifying electrode to earth; the electrode being so sited relative to the spray-head surface that when the spray-head surface is charged, the electrostatic field thereat causes liquid thereon to atomise without substantial corona discharge to form electrically charged particles which are projected past the electrode and into contact with the plant.

Claim 7

In combination with a tractor an attachment for atomising liquid pesticide to form charged atomised spray particles and to project them along trajectories determined primarily by electrostatic forces to contact plants growing in the earth, said attachment comprising: a boom attached to the tractor; sprayheads mounted on said boom each having an at least semi-conducting external surface defining a spray orifice; means for electrically charging each sprayhead surface to a potential of the order of 20 kilovolts; means to flow liquid to and through each orifice under gentle hydrostatic pressure; a field-intensifying electrode mounted adjacent to each orifice and aside from and asymmetrically with respect to each said trajectory; and means for electrically connecting said field-intensifying electrode to the earth in which the electrode being so sited relative to the surface that when the surface is charged by the charging means the electrostatic field thereat is sufficient without substantial corona discharge to draw the liquid out into a regular pattern of ligaments, which ligaments break up into a cloud of charged atomised spray particles which follow said trajectories to the plants so that the cloud wraps around the leaves of the plants and coats both the upper and lower surfaces of the leaves.

Claim 8

In combination with a tractor an attachment for atomising liquid pesticide to form charged atomised spray particles and to project them along trajectories determined primarily by electrostatic forces to contact plants growing in the earth, said attachment comprising: a boom attached to the tractor; sprayheads mounted on said boom each having an at least semi-conducting external surface defining a spray orifice; means for electrically charging each sprayhead surface to a potential of the order of 20 kilovolts; means to flow liquid to and through each orifice under gentle hydrostatic pressure; a field-intensifying electrode mounted adjacent to each orifice and aside from and asymmetrically with respect to each said trajectory; and means for electrically connecting said field-intensifying electrode to the earth in which the electrode being so sited relative to the surface that when the surface is charged by the charging means the electrostatic field thereat is sufficient without substantial corona discharge to draw the liquid out into a regular pattern of ligaments, which ligaments break up into a cloud of charged atomised spray particles which follow said trajectories to the plants so that the cloud wraps around the leaves of the plants and coats both the upper and lower surfaces of the leaves.