Patent ID: 8622495

Claim:
A paper floating detection apparatus which detects floating of paper conveyed along a prescribed conveyance path on a prescribed conveyance surface, the paper floating detection apparatus comprising: a paper floating detection device which includes a light emission unit and a light reception unit disposed so as to be mutually opposing across the conveyance path, and detects whether the paper floats or not according to whether a detection beam emitted parallel to the conveyance surface from the light emission unit toward the light reception unit in a position at a prescribed height from the conveyance surface is received by the light reception unit or not; a light emission parallel flat plate which is disposed in front of the light emission unit in such a manner that the detection beam emitted from the light emission unit passes through the light emission parallel flat plate, and which is provided rotatably about an axis parallel to the conveyance surface and perpendicular to the detection beam in such a manner that the height of the detection beam emitted from the light emission parallel flat plate after passing inside the light emission parallel flat plate varies according to rotation of the light emission parallel flat plate; and a light emission parallel flat plate rotation driving device which drives the rotation of the light emission parallel flat plate.