| 摘要 |
A transfer roller driving unit and an image forming apparatus having the same are provided to prevent a defective transfer by uniformly maintaining the pressure of a transfer roller with respect to a transfer belt even though a driving motor is overrun. A driving unit includes a driving motor, a driving cam(91) rotated by the driving motor, a position sensor(85) for detecting a position of the driving cam, and an ON/OFF driver for turning on or off the driving motor according to a signal of the position sensor and a printing command. A driving lever(101) is formed such that one side thereof is provided to be rotatable centering around a certain rotation axial line and the other side thereof is able to contact with the driving cam, and has one region combined with a transfer roller(60). An elastic member presses the driving lever to allow the transfer roller to come in contact with a transfer belt(40). A movement restricting unit(110) restricts movement of the driving lever such that the driving cam does not contact with the driving lever at a certain contact section where the transfer roller contacts with the transfer belt. |
