Patent ID: 7257339

Claim:
An image forming apparatus, comprising: at least one image carrying member configured to form a toner image on a surface thereof; a transfer member having a surface facing the at least one image carrying member and configured to transfer the toner image to a recording medium; a plurality of support rollers supporting the transfer member; and a detecting mechanism configured to detect a speed of the transfer member, comprising: a detection roller including at least one support roller selected from the plurality of support rollers; a roller shaft provided to the detection roller; a moving member configured to rotate with the detection roller and directly fixed to the roller shaft; a sensor configured to detect a moving speed of the detection roller with the moving member; and a controller configured to control a traveling speed of the transfer member to a target speed based on a detection result of the sensor, wherein a moment of inertia of the detection roller is substantially 35 (kgf·cm 2 ) or less.