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One of the main elements of safe operation of gravity conveyors used in gravity racks for pallets is the brake roller. The most promising design is a brake roller of magnetic (eddy current) type. A mathematical model of the process of moving pallets on a magnetic brake roller is developed. The equation of the speed of movement of the pallets on the brake magnetic roller obtained. The main parameter that determines the braking functions of the brake magnetic roller, and therefore the speed of movement of the pallet on the gravity roller conveyor is the coefficient of roller, experimental studies have been carried out to determine the magnetic viscosity coefficient. It was found that the coefficient of magnetic viscosity decreases with increasing air gap between the conductive body and the permanent magnets, and this dependence has a power-law character; decreases by 10... 25% with increasing speed of the conductive body; independent of changes in the distance between the centers of the conductive body and the permanent magnet; decreases when an edge effect appears in accordance with the air gap.

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Pallet flow rack are widely used in intralogistics to maximize warehouse capacity and to reduce the travel by fork-lifts. However, the use of pallet flow racks is associated with increased danger due to the use of gravity conveyors in their design. For this purpose, the gravity conveyors of pallet flow rack have a two safety elements – brake rollers and a stopping mechanism with pallet separator, which are working as a system. Brake rollers limit the speed of pallets, while the stopping mechanism allows exuding a pressure on the unloading pallet from the following behind it. A pallet should have such a speed, controlled by the brake rollers, so that it could be stopped by a stopping mechanism without damaging it. Based on the Cox impact theory, an original method for determining the allowable speed of a pallet in a pallet flow rack is proposed. The method ensures safe operation of the stopping mechanism with pallet separator and takes into account the mechanical properties and design parameters of the pallet separator stopper. A calculation example is provided for the most commonly used types of pallets – Euro pallet (1200 mm × 800 mm) and Industrial pallet (1200 mm × 1000 mm). The obtained results agree well with the pallet speed range of 0.2 to 0.3 m/s recommended by the manufacturers of pallet flow racks.

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