US Patent 7731322 Image forming apparatus

An image forming apparatus can form a high-quality image while acquiring a stable conveyance performance. A conveyance belt (21) conveys a recording medium (12) by attracting the recording medium (12) by an electrostatic force. A recording head (7) discharges liquid droplets toward the recording medium (12) being conveyed by the conveyance belt (21). Alternating positive and negative electric charges are applied onto the conveyance belt (21). A conveyance speed is controlled in accordance with a charge period length of the alternating positive and negative electric charges applied onto the conveyance belt (21).