Image forming apparatus having variable transfer and attraction voltage
US5799225A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 1995 |
| Grant date | Aug 25, 1998 |
| Priority date | — |
| Expiry date | Sep 29, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G2215/1657
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An image forming apparatus includes a transfer drum which attracts and holds a transfer paper electrostatically. A toner image formed on a photosensitive drum is transferred onto the transfer paper when the transfer paper is wound around the transfer drum and brought into contact with the photosensitive drum. A variable voltage is applied to a conductive layer provided on an inner side of the transfer drum so as to either transfer the image onto the transfer paper or attract the transfer paper to the transfer roller. The transfer voltage is lower than the attracting voltage. The voltage applied to the transfer drum for both transfer and attraction will be variable depending on a detected humidity or type of transfer paper. In addition, a manual adjusting device is capable of adjusting the transfer or attraction voltage. A grounded conductive electrode roller is pressed against a dielectric layer provided on an outer side of the transfer drum for providing potential difference between the conductive layer and the transfer paper.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.