Patent ID: 8223386

Claim:
An image forming apparatus comprising: an image forming device for forming a reference image at a position which is away from a leading edge of a first surface of a sheet by a prescribed length, and for forming an image for the first surface with reference to the position of the formed reference image; a reversing device for reversing the sheet on which the reference image and the image for the first surface are formed by the image forming device; a first detecting device for detecting a leading edge of a second surface of the sheet reversed by the reversing device; and a second detecting device for detecting the position of the formed reference image of the sheet with reference to the leading edge of the second surface detected by the first detecting device, wherein a reverse sheet conveyance path for reversing the sheet in terms of front and rear surfaces is provided on the reversing device, wherein the first and the second detecting devices are provided on the reverse sheet conveyance path, and the first detecting device is arranged at a location on a downstream side and in a vicinity of a first conveyance roller from among a plurality of conveyance rollers in a straight path of a sheet re-supply section of the reverse sheet conveyance path, and wherein the image forming device forms an image on the second surface of the sheet with reference to the position of the formed reference image on the sheet detected by the second detecting device, a reference point of the position of the formed reference image being the leading edge of the second surface of the sheet.