Image forming apparatus having a heat insulation duct that discharges a cooling medium

An image forming apparatus comprising:

• an image former that includes an imaging part that forms a toner image, a transferrer that transfers the toner image onto a sheet, and a transfer belt;
• a fixing apparatus that fixes the toner image transferred to the sheet by a heating roller and a pressure roller extending in an axial direction,
• the transfer belt from the transferrer to the imaging part being disposed to at least partially surround an upper side of the fixing apparatus and an upstream side, relative to a sheet conveyance direction, of the fixing apparatus;
• and
• a first heat insulation duct that is disposed between the upper side of the fixing apparatus and the transfer belt and introduces a cooling medium therein along the axial direction and a second heat insulation duct that is used together with the first duct, is disposed between the upstream side of the fixing apparatus and the transfer belt, and introduces the cooling medium therein along the axial direction,
• wherein the second heat insulation duct has an opening portion that discharges the cooling medium introduced into the second heat insulation duct to a region between the image former and the fixing apparatus.