An image forming apparatus includes a photoreceptor belt formed by either a belt
or a thin-walled cylinder. A charging unit that sets bias characteristics of the
photoreceptor belt has an arrangement to approach towards the photoreceptor belt.
A damper is provided on a side of the photoreceptor belt opposite to the side facing
the charging unit. The damper absorbs vibrations in the photoreceptor belt through
a supporting plate.