A downwardly conveying conveyor installation, such as belt-conveyor installation, for transporting the conveyable articles along a conveying path from a geodetically higher location to a geodetically lower location. There is provided a motor drive, and a hydrodynamic coupling comprising a drive-side pump wheel and an output-side turbine wheel, which together form a toroidal operating space which is filled with operating medium. The pump wheel and the turbine wheel each have a blade arrangement with a multiplicity of blades which are arranged opposite one another such that the blades of the pump wheel are flush with the blades of the turbine wheel. The blades of the pump wheel, as seen in a circumferentially directed section through the operating space, are positioned obliquely, in the direction from the rotor base to the blade tip, counter to the driving direction of rotation of the pump wheel, and the blades of the turbine wheel are positioned obliquely, in the direction from the rotor base to the blade tip, in the driving direction of rotation of the turbine wheel.