A rotor core is provided with a pole piece portion holding a magnet and a balance weight portion, wherein said hub fitting hole is inserted a metal hub having a tapered axis hole and part fitting portion so as to be fixed each other, and said rotor core is coated with synthetic resins, thereby the use of metal can be limited only to parts where mechanical strength is required so that the whole rotor weight can be reduced and can be assembled easily, and be allow various parts can be fitted stably, and the degradation of magnetic properties of the magnet can be prevented.
A reluctance motor is provided that reduces leaking magnetic flux. To generate magnetic flux between adjacent magnetic poles in a rotor 2, permanent magnets 4 are disposed in approximate centers of split magnetic paths near a borderline area between two magnetic poles in an internal portion of the rotor. Further, each of slots 8 in a stator 1 is wound with a coil of a corresponding phase such that the vector phase and amplitude expressed by the products of the number of coil turns and the amount of passing current, namely, ampere-turns, become almost identical for each of the slots. By reducing leaking magnetic flux according to this arrangement, generated torque can be increased. As the rotor mechanical strength is enhanced, the rotor can be safely driven at a higher speed. A practical motor is obtained that simultaneously achieves improved motor characteristics and reduced torque ripples.
A rotor core, rotating in the vicinity of a generating coil, comprises a balance weight section and a pair of magnetic poles, provided on opposite sides of the balance weight section 2 with respect to a center of rotation O of the rotor core 1 to sandwich a magnet, and confronting through a magnetic gap G. A magnet holding section 9 for preventing the magnet 5 flying out through the magnetic gap G due to centrifugal force, is provided integrally contiguous to each of the magnetic poles so as to connect between the two magnetic poles.
An electric stepper motor includes a thru-hole, a rotor and a stator. The rotor consists of a pair of hollow magnetic metal flange-shaped laminations arranged within a hollow magnetic sleeve. The motor can be field-converted from rotary to lineal translation by attachment of a threaded nut to the motor shaft mounting face. The thru-hole allows use with a chamber and provides transport of hardware and elements into the chamber.