Closed-loop developability control in a xerographic copier or printer
US5559579A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 1994 |
| Grant date | Sep 24, 1996 |
| Priority date | — |
| Expiry date | Sep 29, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G2215/00042
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A developer control for enabling the use of developer and toner materials with widely varying At in high quality xerographic copying and printing. Pixel count data is combined with toner test patch reflectance data during a brief toner rundown to determine the rate of change of density per unit change in toner concentration. During toner rundown, dispensing of toner is suspended for a period of time for effecting toner concentration reduction by approximately 0.25%. The change in Toner Concentration (TC) is estimated using pixel counting. Additionally, toner test patches are created and the reflectance thereof is measured for determining the change in toner density. The estimated TC change and the change in toner density are processed using linear regression to find the average change in density sensor output for the estimated change in TC which is referred to as the rundown slope. The rundown slope is then compared to a target value. If it exceeds the target value by more than ? (a noise factor), the dispense setpoint is reduced by one unit. If the rundown slope is less than the target value by more than ?, the dispense point is increased by one unit. The noise factor, ? is attrib…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.