Image forming apparatus
US9256188B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 19, 2015 |
| Grant date | Feb 9, 2016 |
| Priority date | — |
| Expiry date | Mar 19, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/065
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An image forming apparatus having image supporting members and developing devices provided for a plurality of colors respectively, and a developing bias source. The developing bias source includes DC power circuits provided for the colors respectively, an AC power circuit provided for use in common for all of the colors, and an element provided for at least one of the colors other than black. The developing bias source generates developing biases by superimposing an AC voltage output from the AC power circuit on DC voltages output from the DC power circuits and applies the developing biases to the respectively corresponding developing devices. The element maintains a constant voltage having a potential of an opposite polarity to a potential of charged toner used for the development. The developing bias source further superimposes the constant voltage on the developing bias for the at least one of the colors other than black.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.