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AssigneeSiemens Aktiengesellschaft
InventorJoseph Knott
Estimating the term…
In a developing station functioning on the principle of cross-blending in an electrophotographic printing device, two mixing screws running in opposite directions are arranged at a distance from one another. The first mixing screw is situated in a mixing trough provided with a plurality of oblique slots and comprises two mixing strips in the delivery region of the developer mix which are offset by 180.degree. and which neighbor one another. A scraper strip having an actual scraping region and scraping teeth is situated above the two mixing screws. A metering baffle is arranged at an angle relative to this scraper strip, this metering baffle extending through the teeth of the scraper strip and including baffles at its lower end for controlling the flow of the developer mix.
In a mixing device for blending a developer composed of carrier particles and toner for developing charge images applied to a charge image carrier in a developing station including a first mixing screw in a mixing chamber arranged parallel to a developing drum, said first mixing screw moving the developer from a delivery region parallel to said developing drum in a mixing through while blending it, a second mixing screw arranged below said first mixing screw for returning said developer along said developing drum, whereby said developing drum constantly conveys a part of said developer from said developing drum to said charge image carrier, and wherein a scraper strip arranged above said mixing screw picks up developer adhering to said developing drum and supplies it at least partially to said first mixing screw via a guide means, the improvement comprising wherein at least in the delivery region, said mixing trough of said first mixing screw includes axially extending mixing strips located at the circumference of the mixing screw extending over a plurality of spirals of said mixing screw for fast blending of the supplied developer and said mixing trough includes a plurality of openings via which said developer is supplied to said second mixing screw essentially over the full width of said mixing screw.
In a mixing device for blending a developer composed of carrier particles and toner for developing images applied to a charge image carrier in a developing station including a first mixing screw in a mixing chamber arranged parallel to a developing drum, said first mixing screw moving the developer from a delivery region parallel to said developing drum in a mixing trough while blending it, a second mixing screw arranged below said first mixing screw for returning said developer along said developing drum, whereby said developing drum constantly conveys a part of said developer from said developing drum to said charge image carrier, and wherein a scraper strip arranged above said mixing screw picks up developer adhering to said developing drum and supplies it at least partially to said first mixing screw via a guide means, the improvement comprising wherein at least in the delivery region, said mixing trough has a trough height decreasing in a conveying direction of said developer, so that developer passes over the edge of said mixing trough into said mixing chamber beginning with a prescribed filling degree, and includes mixing strips located at the circumference of the mixing screw extending over a plurality of spirals of said mixing screw for fast blending of the supplied developer and said mixing trough includes a plurality of openings via which said developer is supplied to said second mixing screw essentially over the full width of said mixing screw.
Dependencies are inferred from the claim text.