Patent ID: 7592720

Claim:
A magnetic drive system for driving a door leaf of a sliding door in a driving direction, comprising: a carrying slide for carrying the door leaf; a row of magnets supported by the carrying slide and disposed in the driving direction, the row of magnets having a length L and a longitudinal direction, the magnets being arranged so that magnetizations of the magnets reverse at a predetermined interval in the longitudinal direction; a coil arrangement comprising a plurality of coil cores and a plurality of coils which are wound around respective coil cores, the carrying slide being movable relative to the coil arrangement along a travel path V; and a displacement measuring system cooperating with the row of magnets as a magnetic measuring scale for measuring a position of the carrying slide along the travel path V, the displacement measuring system comprising a first magnetically sensitive position sensor and a second, adjacent magnetically sensitive position sensor which is separated from the first position sensor by a distance A, the adjacent first and second position sensors being separated by at least one of the plurality of coils, wherein when energized, the coils interact with the magnets to generate a thrust force for driving the carrying slide in the driving direction along the travel path, wherein the distance A is larger than the difference between the length L and the travel path V and smaller than the length L, and wherein the first and second position sensors are disposed so that the travel path V is subdivided into two measuring ranges of the first and second position sensors.