Transfer roller device
US5075731A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 1991 |
| Grant date | Dec 24, 1991 |
| Priority date | — |
| Expiry date | Mar 12, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/1605
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A transfer roller device for transferring onto a copy paper sheet a full color toner image formed on an intermediate transfer belt. A rear-surface electrode roller disposed at the opposite side to a transfer roller with the intermediate transfer belt positioned in between, is divided into a plurality of cylinder members, and at least one of the cylinder members corresponding to the size of a copy paper sheet is separately connected to ground. With the arrangement, occurrence of an excess current through a portion of the intermediate transfer belt carrying no copy paper sheet thereon is eliminated, thereby preventing a filming phenomenon. In another arrangement, a plurality of rear-surface electrode rollers are disposed at respective positions associated with a plurality of respective copying speeds which are set according to copy paper sheets. Thus, a voltage to be applied between the transfer roller and the rear-surface electrode roller is maintained constant regardless of different copying speeds.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.