Patent ID: 8208846

Claim:
An image forming apparatus, comprising: an apparatus main body; an image forming assembly arranged in the apparatus main body for transferring a toner image formed based on image information to a sheet; a sheet tray on which a sheet to be subjected to an image transfer process is to be placed; a conveyance unit detachably insertable into the apparatus main body, provided between the sheet tray and the image forming assembly and adapted to convey the sheet on the sheet tray toward the image forming assembly, the conveyance unit having an engaging portion; an openable and closable cover member provided on a wall of the apparatus main body facing a downstream end of the conveyance unit in a sheet conveying direction, the cover member having a contact surface; a vertical conveyance path defined at an inner side of the cover member by closing the cover member for further conveying the sheet conveyed by the conveyance unit upward; and a locking mechanism for preventing the conveyance unit from being pulled out from the apparatus main body with the cover member closed, wherein the locking mechanism includes a locking rod that is arranged between the cover member and the conveyance unit and that operates as the cover member is opened and closed, the locking rod including a first end located at a side toward the cover member, a second end located at a side toward the conveyance unit and a first biasing member for biasing the locking rod in a direction toward the first end, wherein the contact surface of the cover member pushes the first end to move the locking rod in a direction toward the second end against a biasing force of the first biasing member, thereby engaging the second end of the locking rod with the engaging portion with the cover member closed, whereas the biasing force of the first biasing member moves the locking rod in the direction toward the first end of the locking rod to release the engagement between the second end with the engaging portion with the cover member opened so that the locking rod interferes with the conveyance unit with the cover member closed and does not interfere with the conveyance unit with the cover member opened.