Patent ID: 8502422

Claim:
A sorting system including a conveyor comprising a plurality of carts for carrying articles, a track along which the carts may be driven, a propulsion system for providing a driving force to the carts for moving the carts along the track, said propulsion system comprising at least one stationary stator having a plurality of coils arranged to generate magnetic fields when electrical power is applied, and reaction elements each respectively mounted on each of the carts, said reaction elements each comprising a plurality of permanent magnets connected to at least one plate-like carrier, and said reaction elements being arranged on the carts in order to interact with the magnetic fields generated by the coils of the stator, as well as a controller for controlling a supply of electrical power to the stator in order to provide a driving force via the reaction elements to the carts when power is applied, where the reaction elements each comprises a number of permanent magnets arranged with alternating polarity, and where the magnets on reaction elements of two adjacent carts are arranged to form a longitudinal row of magnets as seen in a transport direction of the carts, said row having two neighbouring magnets, at least one of said two magnets having, in the transport direction, a reduced dimension compared to other magnets of the reaction element, said two neighbouring magnets being located at each side of a transition between said two adjacent carts.