Abstract: A fiber bale opener includes a truck arranged for back-and-forth movement along a traveling path, for removing fibers from bales arranged along the traveling path. The bale opener further includes a stationary suction duct extending in the direction of the travelling path and having a throughgoing slot on one side thereof, extending parallel to the traveling path. A flexible cover belt extends over the slot for sealing the inside of the duct from the environment and defining an interstice within the truck. The interstice travels with the truck and provides a passage for the fiber to pass inside of the suction duct. A deflection roller is fixed to the truck and the cover belt is positioned above the slot and is divided into an upper and lower section with the lower section covering the longitudinal slot. The cover belt has one end fixed at one end of the traveling path and is guided around the deflection roller.