Image forming apparatus having roller cleaning system and method
US5873019A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 3, 1997 |
| Grant date | Feb 16, 1999 |
| Priority date | — |
| Expiry date | Feb 3, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/0225
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An image forming apparatus of a type having a photoconductive drum surrounded by an exposure station, a toner dispenser, an image transfer roller, a pre-discharging lamp and a contact charging roller incorporates a novel apparatus and method for cleaning the transfer and charging rollers of toner and other contamination. The transfer roller first is cleaned by applying to it an electric bias of alternating polarity to repel toner to the photoconductive element. Charge induced on the photoconductive drum by the toner is neutralized by the contact charging roller, and thereafter, a cleaning element, such as a sponge, is moved into contact with the charging roller for cleaning it of toner. The transfer roller may be separated from the photoconductive drum during image exposure or in response to an exposure synchronization signal, to reduced image distortion caused by mechanical vibration of the drum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.