| 摘要 |
PROBLEM TO BE SOLVED: To prevent skew of a belt member to obtain excellent belt traveling property by play on a driven roller side in relation to a drive roller in a separation state and holding of parallelism between the drive roller and the driven roller in a mounting state.SOLUTION: An image forming apparatus includes: a belt member 10 wound between a drive roller 8 and a driven roller 9; frame members 51 and 52 for supporting a shaft portion 80 of the drive roller 8; and support means 130 for supporting a shaft portion 90 of the driven roller 9 to be movable in an oscillating direction C parallel to an axis direction of the shaft portion 80 of the drive roller 8 and different from the axis direction. The image forming apparatus further includes: a transfer device 50 detachable from an image forming apparatus body 100; a positioning section 104 which is provided in the image forming apparatus body 100 and holds the shaft portion 80 of the drive roller 8 in parallel when mounting the transfer device 50 in the image forming apparatus body 100; and a regulation section 105 which is provided in the image forming apparatus body 100, regulates the movement of the driven roller 9 in the oscillating direction C when mounting the transfer device 50 in the image forming apparatus body 100 and holds the shaft portion 80 of the drive roller 8 and the shaft portion 90 of the driven roller 9 in parallel. |
