To improve motor performance and lower manufacturing costs, rotor-embedded flat NdFeB magnets replace surface-mounted curved magnets. The design effectively doubles the magnet's power volume providing flux for higher torque to inertia, and reduced size and weight.
Stainless-steel center shaft, non-magnetic-retainer rings and glass-fiber rods prestress the rotor assembly. The prestressed rotor cage delivers torque allowing center-shaft elimination in small-diameter motors. High mechanical stiffness allows increased current-loop gains.
The design secures magnets even at high speeds, eliminating the need for special rotor banding. Schlenker Enterprises has designed the synchronous ac servo motor in four diameters rated from 1 Nm to 147 Nm.
Schlenker Enterprises Ltd., 5143 Electric Ave., Hillside, IL 60162-1099, Fax: (708) 449-5703.