Patent ID: 8757390

Claim:
A separating device for concentrating ores and other particulate materials, the separating device comprising: a material feeder for carrying a feed material comprising a fraction of nonmagnetic feed material, a fraction of weakly paramagnetic feed material, and a fraction of moderately paramagnetic feed material, a metal traction roller that rotates in a direction to cause the feed material to fall from the material feeder, wherein a mantle of the metal traction roller is covered substantially completely by a multiplicity of permanent magnets, each having a magnetic axis and a polarity, wherein the permanent magnets are installed in proximity to each other, such that their magnetic axes are perpendicular to a radial axis of the fraction roller and their polarities are oriented at random, a sleeve of nonmagnetic plastic material that covers about 200 sexagesmial degrees of a cross section of the traction roller along the entire width of the traction roller, a first deflector that separates the fraction of moderately paramagnetic feed material from the fraction of weakly paramagnetic feed material during the fall of the feed material from the material feeder, a second deflector positioned on a plane that intersects the traction roller, such than an edge of the deflector is in a zone where the fraction of nonmagnetic feed material moves away from the traction roller during the fall of the feed material from the material feeder, and a tensioning roller positioned between a pulley and the traction roller, wherein the tensioning roller varies an angle of emergence of about 45 sexagesimal degrees from the vertical of the axis of the metal traction roller.