The University of Western Ontario

Quebec Metal Powders Limited

Southwest Electrostatic Sprayers, Inc.

James D Brown

Ion I Inculet

G S Castle

Thomas E Doyle

Richard B Dobbins

Paul F Wynen

Peter Hansen

An apparatus for tribocharging particles of electrically insulating materials has a rotatable drum (), made of a metallic material, for containing the particles. The drum has an inlet (), for charging material, and an outlet (), for discharging material. The drum further has means () for rotating the drum about an axis of rotation, the orientation of the axis of rotation being such that, in operation of the apparatus, the particles tumble against each other and against the walls of the vessel, thereby becoming tribocharged. A fines removal mesh screening means () is attached to an outer surface of the drum, allowing fines to escape from the drum. An electrostatic separation tower (), having tapering walls and at least one pair of electrodes () arranged on opposite walls of the tower, is aligned to receive discharged material from the drum. The tower separates the particles, falling from the drum into the tower (), in an electric field generated between the electrodes ().

Tribocharging and electrostatic separation of mixed electrically insulating particles

A method of making a metal composite part by compacting a metal powder composition in a die whose wall surfaces have been electrostatically coated with a lubricant, thereby eliminating or reducing a lubricant in the metal powder composition, resulting in a metal composite having greater density and strength. The method further includes providing an electrostatic charge to the metal powder composition. A powder metallurgy apparatus is also provided.

Powder metallurgy apparatus and process using electrostatic die wall

A mixture of particles of plastic materials having different work functions is fed through a rotating tube. The tube rotates about an axis which is inclined slightly to the horizontal. The tube is of plastic or metallic material, preferably having a rib for stirring the mixture. As the particles pass progressively down the length of the tube, the triboelectrically induced charge progressively increases, whereby the particles are highly charged upon emerging from the tube. The tube may be made of the same material as a minority component of the mixture to bring up the level of the charge on the majority component.

Electrostatic separation of mixed plastic waste

A portable electrostatic liquid sprayer including a small internal combustion engine with a magneto-type ignition system providing a high voltage source to inductively charge atomized droplets being sprayed onto crops or plants. A conductive voltage tap is coupled between a spark plug boot from the magneto and the high voltage terminal of a spark plug for access to the high voltage provided by the magneto. A wire is connected to the voltage tap and routed and connected to an RC filter and rectifier circuit mounted in the sprayer head. A ground wire is electrically coupled to the chassis of the engine and also routed and connected to the RC filter and rectifier circuit. An electrode mounted near the outlet of the sprayer head and connected to the RC filter and rectifier circuit establishes an electrostatic field within the sprayer head effective to inductively charge the atomized droplets as they are being ejected from the sprayer head.

Growing community of inventors

London, Canada

James D Brown