초록 ▼

An electrographic copier/duplicator has a development station with a sump for holding a supply of two-component developer material. A magnetic brush applies the developer material to a photoconductor moved past the magnetic brush. The developer material may comprise carriers of hard, magnetic materi

An electrographic copier/duplicator has a development station with a sump for holding a supply of two-component developer material. A magnetic brush applies the developer material to a photoconductor moved past the magnetic brush. The developer material may comprise carriers of hard, magnetic material. A ribbon blender mixes the developer material in the sump. The blender includes first and second ribbons with each ribbon having a first, relatively large diameter helical end portion and a second relatively small diameter helical end portion. The second end portion of each ribbon is located substantially within the first end portion of the other ribbon. Because the two end portions of the ribbon are connected, there is good axial mixing of developer material in the area between the two portions of each ribbon, and the level of the developer material tends to remain level throughout the length of the ribbon blender. Replenishment of depleted toner particles can occur in the area between the first and second end portions of the ribbons.

대표청구항 ▼

In development apparatus having a sump for developer material comprising hard magnetic carrier particles and toner particles, a ribbon blender for mixing developer material in the sump, and means for transporting developer material from the sump to a latent image on a photoconductor, an improved rib

In development apparatus having a sump for developer material comprising hard magnetic carrier particles and toner particles, a ribbon blender for mixing developer material in the sump, and means for transporting developer material from the sump to a latent image on a photoconductor, an improved ribbon blender comprising: a rotatable shaft, first and second continuous elongate ribbons coiled around the shaft, each of the ribbons having first and second generally cylindrical helical portions with the first helical portion being larger in diameter than the second helical portion, the first ribbon having its second portion located within the first portion of the second ribbon, the second ribbon having its second portion located within the first portion of the first ribbon, and means for supporting the ribbons from the shaft so that rotation of the shaft effects rotation of the ribbons.