Image forming apparatus to prevent air duct bending

An image forming apparatus comprising:

• a photosensitive member;
• a transfer unit including:
• a transfer belt onto which a toner image formed on a photosensitive member is transferred;
• a primary transfer roller that faces the photosensitive member via the transfer belt and forms a primary transfer nip portion for primarily transferring the toner image formed on the photosensitive member to the transfer belt;
• a secondary transfer inner roller that is provided below the primary transfer roller in a vertical direction and in contact with an inner circumferential surface of the transfer belt;
• and
• a stretching roller for stretching the transfer belt that is provided between the secondary transfer inner roller and the primary transfer roller in a rotation direction of the transfer belt;
• a secondary transfer outer roller configured to face the secondary transfer inner roller via the transfer belt and to form a secondary transfer nip portion for secondarily transferring the toner image formed on the transfer belt to a recording material;
• a support unit configured to support the transfer unit to move along a rotation axis direction of the secondary transfer inner roller;
• an air duct which includes a joint portion with a second duct and is provided in the transfer unit and is configured to move integrally with the transfer unit along with movement of the transfer unit from the support unit;
• and
• a sealing member provided between the joint portion of the air duct and the second duct to seal the joint portion of the air duct.