Toner control system and method for electrographic printing
US5369476A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 1992 |
| Grant date | Nov 29, 1994 |
| Priority date | — |
| Expiry date | Jan 28, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G2215/00067
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Toner control system and method for an electrographic printer in which toner is delivered from a reservoir to a toner fountain and there applied to an electrostatically charged sheet to form an image. The visual quality of the image is monitored, and toner concentrate is added to the toner in response to the monitored quality to increase the amount of pigment particles in the toner and thereby maintain a substantially constant image quality. The concentrate is added to the toner in a return line between the fountain and the reservoir in relatively small, predetermined amounts, and it is mixed before being added. In the disclosed embodiments, a test image is formed outside the main image on the sheet, and the brightness of one or more predetermined colors in the test image is monitored. This system and method are applicable both to monochrome images and to multicolor images.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.