An image forming apparatus includes an imaging assembly capable of forming an image on a copy sheet; a sheet inverting path disposed downstream of the image assembly and capable of transporting the copy sheet in a first direction; an intermediate tray unit arranged downstream of the sheet inverting path...http://www.google.com/patents/US5857138?utm_source=gb-gplus-sharePatent US5857138 - Image forming apparatus capable of double-sided copying and provided with intermediate tray on which feed direction of copy sheet is inverted
