Image forming apparatus

An image forming apparatus comprising:

• an image forming device configured to form an image on a sheet;
• a fixing device configured to heat and fix the image on the sheet;
• a first conveyance passage downstream from the fixing device in a sheet conveyance direction, the first conveyance passage including a sheet outlet from which the sheet is ejected to an outside of the image forming apparatus;
• a second conveyance passage downstream from the fixing device in the sheet conveyance direction, the second conveyance passage communicating with the first conveyance passage;
• a sheet reversing member configured to reverse a conveyance direction of the sheet and convey the sheet to the second conveyance passage;
• a divider configured to switch a conveyance route of the sheet between the first conveyance passage and the second conveyance passage;
• a cooled section including a board to be protected from heat;
• a suction device configured to introduce air into the image forming apparatus via the cooled section;
• a third conveyance passage between the suction device and the first and second conveyance passages;
• a sheet detection sensor downstream from the fixing device and upstream from the divider in the sheet conveyance direction;
• and
• a ventilation passage communicating with the outside of the image forming apparatus and configured to guide the air introduced by the suction device into the third conveyance passage from the cooled section, to pass the sheet detection sensor and to enter at least one of the first conveyance passage and the second conveyance passage, and
• wherein the ventilation passage communicates with the sheet outlet and is configured to vent the air from the sheet outlet.