Developing station for developing charge images generated on a charge image carrier

摘要

In a developer station for an electrophotographic printing or copying machine, there is provided apparatus which effects a more reliable uniform inking of charge images contained on a charge image carrier and which prevents spotting of printed images due to the unintended presence of carrier particles on the charge image carrier. The apparatus includes an evacuator device disposed at the air gap between the developer drum and charge image carrier preceding the inking gap formed therebetween for removing toner deposits which may accumulate at that portion of the developer station housing. A magnetic drum is disposed at the carrier exit end of the station housing for removing carrier particles from the charge image carrier which may have unintentionally become attached to the carrier surface in the area of the inking gap. Devices including an adjustable doctor strip and narrow developer transport channel along the developer drum are provided to control the layer thickness of mix being transported from the mix supply pile in the housing to the inking gap. A mixing screw arrangement is disposed in the developer station housing for blending fresh toner with used developer mix and conducting the enriched mix through the developer station in such a manner that sufficient toner concentration is maintained in the mix throughout developer operation. A sealing plate is disposed along the carrier exit end of the developer station housing to prevent toner dust from emerging from the housing to contaminate the charge image carrier. A plate is disposed between the body of mix in the housing and the developer drum to keep the mix from pressing against the drum and interfering with its rotation.