Medium loading device, feeding device, image reading device, and image forming device

A medium loading device comprising:

• a placement part where a medium is placed;
• a first regulating part and a second regulating part configured to be able to adjust a position of the medium placed on the placement part in a width direction intersecting a feeding direction of the medium;
• and
• an interlocking mechanism configured to move the first regulating part and the second regulating part in an interlocking manner, wherein
• the interlocking mechanism includes:
• a first rack part coupled to the first regulating part;
• a second rack part coupled to the second regulating part;
• a first pinion gear meshing with the first rack part;
• a second pinion gear disposed in a first direction of the first pinion gear and meshing with the second rack part;
• an energizing part configured to energize the first pinion gear and the second pinion gear in a direction away from each other along the first direction;
• a first rotating part located between the first pinion gear and the energizing part in the first direction and configured to be rotatable together with the energizing part;
• and
• a second rotating part located between the second pinion gear and the energizing part in the first direction and configured to be rotatable together with the energizing part, and
• when the second regulating part is fixed and the first regulating part is moved in the width direction, the second pinion gear stops, the first pinion gear rotates, and the first rotating part, the second rotating part, and the energizing part rotate or stop in a unified manner.