Patent ID: 7990084

Claim:
A linear stepping motor comprising: a plate-shaped stator having a plurality of teeth symmetrically formed on upper and lower surfaces thereof at regular pitch; a movable member which includes a plurality of upper cores disposed above the stator, a plurality of lower cores disposed below the stator in symmetrical with the upper cores, and yoke parts connecting the upper and the lower cores around the stator, wherein the upper and lower cores have upper and lower coils individually wound around thereof, respectively; at least one non-contact type gap sensor to detect the gap between the stator and the upper or lower core; a controller calculating voltages for levitation and linear movement of the movable member, based on the gap variation; and a multi-channel voltage-to-current power amplifier having a plurality of channels, each channel being connected to each coil of the upper and lower cores, respectively, thereby achieving an independent levitation of the movable member and linear driving of the linear motor.