Accumulating conveyor

A conveyor comprising:

• a helical track having an inner rail and an outer rail surrounding the inner rail;
• and
• a conveyor belt which is drivable along the helical track, the conveyor belt comprising:
• a flexible conveyor line;
• and
• a plurality of slats mounted to the conveyor line, wherein each of the slats includes a guide roller mounted thereto to move with each associated slat, each guide roller having an axis of rotation including a vertical component, wherein each guide roller is upwardly, downwardly and radially supported by the inner rail, wherein an upper contact location between each guide roller and the inner rail where each guide roller is radially supported lies above a line along which a resultant radial force of the conveyor line towards a centerline of the inner rail acts, and wherein each of the slats is upwardly supported by the outer rail and movable in upward direction with respect to the outer rail.