Method and apparatus for singulating particles in a stream

A method for separating particles into a plurality of paths in response to a detected condition of the particles, the method comprising:

• carrying particles to be sorted in a supply conduit;
• forming the particles from the supply conduit into a stream of the particles in a row in at least one duct;
• said at least one duct being shaped and arranged so that the particles are accelerated as they pass from an inlet end of said at least one duct to a discharge end of said at least one duct so as to cause the particles separated into said at least one duct to be aligned one after another in a singulated row of the particles in said at least one duct as they move toward the discharge end;
• locating a first particle separating device at the stream operable to direct each particle into a selected one of first and second paths of said plurality of paths;
• wherein the first particle separating device comprises a first separating head having a front edge lying generally along the stream so that particles in the stream move toward the front edge, at least first and second side surfaces diverging away from the front edge and an actuator for moving the front edge;
• detecting the condition of the particles in the stream to determine a required separation of the particles by said first particle separating device between said first and second paths and operating the actuator to direct the particles;
• providing in at least one of the first and second paths a second particle separating device in the path operable to direct each particle into a selected one of third and fourth paths of said plurality of paths;
• wherein the second particle separating device comprises a second separating head having a front edge lying generally along the stream so that particles in the stream move toward the front edge, at least first and second side surfaces diverging away from the front edge and an actuator for moving the front edge;
• detecting the condition of the particles in said one of the paths to determine a required separation of the particles by said second particle separating device between said third and fourth paths and operating the actuator to direct the particles.