Abstract: A conveyor belt system having a drive pulley and a closed belt. The drive pulley has a plurality of pulley teeth thereon. The drive pulley has an axis of rotation. The closed belt has a pulley side which faces the drive pulley. The closed belt has a plurality of belt teeth and a plurality of recesses on the pulley side. Each of the recesses has two sides and a base. The drive pulley is configured to rotate about the axis of rotation in order to propel the belt in a drive direction by at least one of the pulley teeth pushing a corresponding one of the sides of one of the recesses. In a cross-sectional view of the drive pulley and the belt taken in a plane which is perpendicular to the axis of rotation, the one pulley tooth only partially fills the one recess.