Image reader and image forming apparatus

An image reader comprising:

• a transparent plate configured to support an original document on which an image is recorded;
• a scanner that is disposed inside a housing, wherein the scanner is configured to read an image of the original document supported by the transparent plate while the scanner moves in a movement direction;
• a guide shaft that extends in the movement direction and is configured to guide the scanner to move in the movement direction;
• and
• an endless belt that is wound around a driving pulley configured to perform rotational driving and a driven pulley configured to be driven to rotate,
• wherein the endless belt is configured to rotate around the driving pulley and the driven pulley to move the scanner guided by the guide shaft,
• wherein at least one of the driving pulley and the driven pulley is attached to the guide shaft, and
• wherein the at least one of the driving pulley and the driven pulley is attached to the guide shaft so that a rotational axis of the at least one of the driving pulley and the driven pulley extends in an up-and-down direction.