Abstract: A method for operating an electrophotographic proofing system for generating color proofs from image information during multiple imaging cycle proofing runs. Charge model information, development model information and toner replenishment model information are stored for each component color. Actual photoconductor charge characteristics are measured during the imaging cycles of the proofing runs. Actual toner characteristics from component color test patches developed during the imaging cycles are also measured. The photoconductor is charged during the imaging cycles as a function of the charge characteristics measured during a preceding imaging cycle for the same component color, and a as function of the charge model information for the color. The photoconductor is toned during imaging cycles as a function of toner characteristics measured from test patches during a preceding imaging cycle for the same component color and as a function of the development model information for the color.

Abstract: A calibration procedure for an electrophotographic proofing system of the type for generating color proofs during multiple image cycle proofing runs from imaging information representative of half-tone color patterns for each of a set of colors by sequentially, during the imaging cycle for each color of the set, charging a photoconductor as a function of a charge model representative of photoconductor contrast voltages as a function of a charging grid voltage, modulating a laser as a function of the color pattern information to expose the photoconductor, and toning the exposed photoconductor as a function of a development model representative of measured developed toner color densities as a function of development voltage.

Abstract: A liquid color toners handling network for an electrographic printer includes a plurality of developing modules. Each developing module in turn includes a toner handling system having a toner supply reservoir with a toner pump coupled to a reservoir outlet. A T-connector is coupled to the toner pump and is further coupled to a toner supply reservoir inlet. A three-way ball valve is coupled in series with the T-connector and an inlet of the developing module. An additional fluid line couples an outlet of the developing module back to the three-way ball valve. This arrangement allows toner to be trapped between the three-way ball valve and developing module inlet so that toner can be supplied to the developing module in an instant-on manner. The handling network further includes a toner carrier pumping module that can be coupled to any one of the supply reservoirs and a toner concentrate supply container associated with each supply reservoir.

Abstract: An apparatus for applying toner particles to a photoconductive surface having multiple magnetic brushes each of which consists essentially of a magnetic inner shaft and a nonmagnetizeable outer sleeve, with both the sleeve and the inner shaft of each brush being capable of independent rotation. The apparatus uses an adjustably mounted doctor blade to apply toner particles to one of the brushes.The rotation of the inner shafts and sleeves of the brushes, the spacings between the brushes, as well as the magnetic attraction between the brushes affords the transfer of toner from this first brush to the other brushes. Following the transfer of toner, each brush is able to apply toner to the photoconductive surface.