Image forming apparatus and tandem image forming apparatus

Abstract

An image forming apparatus has a photoconductive drum or belt supporting a toner image, a transfer member transferring the toner image onto a recording medium, a transportation device transporting the recording medium to between the photoconductor and the transfer member, a charger charging a surface of the transfer member to the anti-polarity of the electric charge of the toner image, a rotation drive unit rotating the transfer member to the same direction of the recording medium transportation, a contacting/removing unit that contacts the transfer member to the image supported member for printing and removes the transfer member from the image supported member when not printing, and a drive force transferring/blocking unit that transfers the drive force from the rotation drive unit to the transfer member before print starting-up and blocking the drive force during printing.