Magnetic field-guided precision linear drive for sub-micrometer range

摘要

A precision drive for planar movement in cartesian or cylindrical coordinate directions has a stator (2) and a rotor (3) with a measurement system and air bearings (4). The stator is approximately square and made of thick ferromagnetic material in the effective working region of the magnet circuit (17). In the four corners are the bearing surfaces (5), acted upon by the air nozzles (6) of the rotor. The stator has pairs of coils (7) in the X- and Y- coordinate directions. The rotor has a frame(9) with the measurement system in a central opening (11). This system comprises a justification device with measuring bodies and a sensor. The frame has four air nozzles at it corners for the air bearings and permanent magnets in its sides.