Image Number 5 for United States Patent #5031002.
A suction type sheet carrying mechanism for a high speed image forming apparatus, in which a sheet is separated from an electrophotosensitive drum by air suction performed by mechanically combining fixed air suction holes of a hollow shaft and rotated air suction holes of belt pulleys. The sheet is stuck onto rotating endless belts and carried along a curved route by air suction performed by combining moving air holes of moving endless belts. High speed air flows through ditches provided on a belt guide board placed under the endless belts. The sheet is carried through a fixing unit under high temperature circumstances by rotating air suction metal rollers arranged perpendicular to the direction in which the sheet is carried. Fixed air suction holes in a hollow shaft and rotating air suction holes at ring-shaped ridges of a cylinder rotated around the hollow shaft of each air suction metal roller combine to form suction to hold the sheet.