| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus which is capable of preventing the occurrence of wrinkles of a recording medium in a fixing process by stably conveying the recording medium separated in a transfer nip part up to a fixing nip part in a vertical conveyance path.SOLUTION: An image forming apparatus 1 includes an image carrier, a transfer roller, a separation needle provided in the vicinity of the exit of the transfer nip part and applying a separation bias to a recording paper after passing through the transfer nip part, to separate the recording paper from the image carrier, a fixing part arranged on the downstream side of the transfer nip part and in an upper position, a printing rate calculation part 101 calculating the printing rate of an area from the top end position of the recording paper in its conveyance direction to a position equivalent to a conveyance distance from the transfer nip part to the fixing nip part, a separation bias calculation part 102 calculating a separation bias value from the printing rate, and a separation bias control part 103 controlling separation bias application at the separation bias value during a period from when the top end of the recording paper passes through the transfer nip part to when the top end of the recording paper enters the fixing nip part. |
