Image forming apparatus having guides for installation and removal of a removal unit

An image forming apparatus, comprising:

• a main frame that comprises:
• a first guide that extends in a first direction;
• a second guide that extends diagonally from the first guide, the second guide having a proximal end located closer to the first guide and a distal end located farther away from the first guide, the distal end of the second guide being located on one side in a second direction perpendicular to the first direction with respect to the first guide;
• a groove recessed from the second guide and having a bottom, the bottom of the groove being located on another side in the second direction with respect to the distal end of the second guide;
• and
• a frame-side connector movably held by the main frame;
• and
• a unit installable in an installation position in the main frame from outside of the main frame, the unit comprising:
• a first reference portion that is received in the groove in a state where the unit is located in the installation position;
• and
• a unit-side connector configured to be connected with the frame-side connector in a state where the unit is located in the installation position,
• wherein the unit is installed in the main frame by:
• a first process in which the first reference portion moves from one side in the first direction to another side in the first direction while being guided by the first guide;
• a second process following the first process, in which the first reference portion moves toward the one side in the second direction while being guided by the second guide;
• and
• a third process following the second process, in which the first reference portion moves toward the another side in the second direction into the groove and the unit is located in the installation position, and
• wherein the unit-side connector engages the frame-side connector in the first process, the frame-side connector moves as the unit-side connector moves in the second process, and the frame-side connector moves as the unit-side connector moves in the third process.