Image forming apparatus including positioning of suction belt conveyance unit

An image forming apparatus comprising:

• a transfer unit including a transfer nip portion configured to nip and convey a sheet, the transfer unit configured to transfer a toner image to the sheet;
• a fixing unit including a fixing nip portion configured to nip and convey the sheet, the fixing unit configured to fix the toner image transferred to the sheet by the transfer unit to the sheet;
• a suction belt conveyance unit arranged between the transfer unit and the fixing unit in a sheet conveyance direction, the suction belt conveyance unit including a belt portion, and a suction portion configured to suck the sheet to the belt portion by sucking air, the suction belt conveyance unit configured to convey the sheet sucked to the belt portion toward the fixing nip portion by rotating the belt portion;
• a first casing;
• a second casing connected to the first casing and configured to support the fixing unit;
• a first positioning portion disposed in the first casing and configured to perform positioning of the suction belt conveyance unit in a predetermined direction along a surface perpendicular to a width direction of the sheet orthogonal to the sheet conveyance direction;
• and
• a second positioning portion disposed in the second casing and configured to perform positioning of the suction belt conveyance unit in the predetermined direction.