Belt conveyor device and image forming apparatus provided with the same

An image forming apparatus comprising:

• a main body;
• an image forming unit provided on the main body, and configured to form an image;
• a belt conveyor device that can be detachably attachable to the main body,
• the belt conveyor device including
• a belt of an endless shape,
• a plurality of rollers where the belt is stretched,
• a main body frame for rotatably supporting the plurality of rollers,
• a first grip portion provided on a first end side of the main body frame in a width direction intersecting a rotational direction of the belt,
• a second grip portion provided on a second end side of the main body frame in the width direction, and
• an electrical contact portion, provided on the second end side of the main body frame in the width direction, to be electrically connected to the main body,
• wherein a center of gravity position of the belt conveyor device is provided on a downstream side of a center of the belt conveyor device and a range where the center of gravity position of the belt conveyor device is provided in a range where the contact portion and the first grip portion are provided, and the second grip portion is provided on an upstream side of the center of gravity position of the belt conveyor device in an insertion direction of the belt conveyor device.