Image forming apparatus having a locking mechanism for a unit

An image forming apparatus, comprising:

• a first unit dismountable mounted on a main body frame;
• and
• a locking mechanism releasably holding the first unit in a state mounted on the main body frame,
• wherein
• the locking mechanism incudes:
• a handle portion disposed on the first unit, the handle portion being movable to and fro in mounting and dismounting directions of the first unit;
• a lock member swingably disposed on the first unit, the lock member having a hook portion engageable with an engaged portion formed on the main body frame;
• and
• a preloading member preloading the lock member in a first direction in which the hook portion engages with the engaged portion,
• as the handle portion is moved in the dismounting direction, the lock member swings in a second direction opposite to the first direction against a preloading force of the preloading member so as to disengage the hook portion from the engaged portion, thereby enabling the first unit to be dismounted from the main body frame,
• the image forming apparatus, further include a second unit mounted on top of the first unit, and
• the lock member has an elevated portion
• that, with the hook portion and the engaged portion in engagement, permits mounting of the second unit and
• that, with the hook portion and the engaged portion out of engagement, restrain mounting of the second unit.

An image forming apparatus, comprising:

• a first unit dismountably mounted on a main body frame;
• and
• a locking mechanism releasably holding the first unit in a state mounted on the main body frame,
• wherein
• the locking mechanism incudes:
• a handle portion disposed on the first unit, the handle portion being movable to and fro in mounting and dismounting directions of the first unit;
• a lock member swingably disposed on the first unit, the lock member having a hook portion engageable with an engaged portion formed on the main body frame;
• and
• a preloading member preloading the lock member in a first direction in which the hook portion engages with the engaged portion,
• as the handle portion is moved in the dismounting direction, the lock member swings in a second direction opposite to the first direction against a preloading force of the preloading member so as to disengage the hook portion from the engaged portion, thereby enabling the first unit to be dismounted from the main body frame, and
• the first unit is an intermediate transfer unit including:
• an intermediate transfer belt which is endless and on which toner images to be transferred to a recording medium are formed sequentially;
• and
• a plurality of suspension rollers around which the intermediate transfer belt is stretched.