A belt conveyor device for construction machines such as road finishing machines with a continuous conveyor belt that is carried in a conveying plane in a conveying duct by drive and tail pulleys situated inside the conveyor belt, and optionally by support rolls, which are installed in a frame structure defining the conveying duct. The drive and tail pulleys can be moved out of the conveyor belt for replacement with an adjustment arrangement that can be installed or integrated into the frame structure.