Patent ID: 8779382

Claim:
A corona-wire unipolar aerosol charger, comprising: a charging chamber; at least one aerosol inlet channel in communication with the charging chamber for introducing an aerosol flow comprising a plurality of particles into the charging chamber; a corona wire, axially disposed on a central line of the charging chamber, the corona wire being adapted to electrically connect to a high voltage direct current source and create a region of plasma for charging at least a part of the particles of the aerosol flow, the corona wire having a leading edge adjacent to the aerosol inlet channel and a distal end; an annular sheath air inlet opening in communication with the charging chamber for radially introducing a sheath air flow into the charging chamber, the sheath air inlet opening being radially corresponding to the corona wire; a porous tube, disposed about the corona wire and covering the sheath air inlet opening for the sheath air flow to pass therethrough; an annual sheath air outlet opening in communication with the charging chamber for redirecting at least a part of the sheath air flow out off the charging chamber; and an aerosol outlet channel in communication with the charging chamber for directing the aerosol flow with the charged particles out off the charging chamber; wherein the aerosol inlet channel, the sheath air inlet opening, the sheath air outlet opening and the aerosol outlet channel are sequentially arranged in an axial direction of the charging chamber, and wherein the aerosol inlet channel is adapted for guiding the aerosol flow into the charging chamber at an angle of 45 degrees with respect to the axial direction of the charging chamber.