US Patent 7281441 Media thickness detector

A media thickness detector includes a driving force transmission part for removing vibration generated from a driving source. A sensing roller feeds media by receiving the driving force through the driving force transmission part. Sensing bearings are installed on bearing holders and rotate about a central shaft under an elastic force so that they are brought into close contact with the sensing roller. A damper member is connected to the central shaft at a position between the bearing holders and absorbs vibration generated in the central shaft. A thickness sensor detects the thickness of media passing between the sensing bearings and the sensing roller based on a rotating amount of the bearing holders.