Patent ID: 6321045
Filing Date: 2001-11-20
Classification: G03G

Abstract:
In an electrostatographic printing system in which there is provided a primary supply of developer material, the developer material comprising toner and carrier and having a toner to carrier ratio (T/C) associated therewith, wherein the developer material in the primary supply of developer material is used for developing electrostatic latent images on a charge receptor,a method of operating the system comprising the steps of:calculating, according to an algorithm, a range of likely change of T/C for a predetermined number of prints made with the system, the range including at least one limit value of T/C, the algorithm including as an input at least one of a limit rate of dispense of new developer into the primary supply and an assumed limit mass per unit area developed by the system;outputting the predetermined number of prints;measuring, after outputting the predetermined number of prints, the T/C in the primary supply;if the measured T/C is outside the calculated range, substituting a substitute value for the measured T/C in a subsequent calculation relating to T/C; andoutputting a print using the substitute value.