A corona charger includes a housing; a corona wire; and a wire replenisher located in the housing, the wire replenisher includes (i) a reversible motor; (ii) a rotatable shaft driven by the motor; (iii) a supply spool supporting a length of the corona wire; (iv) a tension mechanism tensioning corona...http://www.google.es/patents/US6108504?utm_source=gb-gplus-sharePatente US6108504 - Corona wire replenishing mechanism
