Small-sized motor

Abstract

A small-sized motor includes a rotor, which, in turn, includes a shaft, a laminated core forming salient magnetic poles an odd number and mounted on the shaft, windings, each being wound around a plurality of salient magnetic poles, and a commutator mounted on the shaft. Each salient magnetic pole includes an arm portion and wing portions, which are integrated with ends of the arm portion and circumferentially extends symmetrically with respect to the arm portion. When core laminations of the laminated core each has a thickness u, the laminated core has a diameter D, and the wing portion has a thickness t as measured at its root in a radial direction, the thickness t falls within the range from 5.5% the core diameter D as an upper limit to the core-lamination thickness u as a lower limit. Thus, it becomes possible to solve a problem of a rotor having an odd number of poles in that vibration is likely to arise, to thereby suppress vibration, while maintaining a feature of the rotor that a large torque can be produced.

Dependencies are inferred from the claim text.