Abstract: A synchronous motor including permanent magnets inserted in a rotor, said permanent magnets having azimuth positions within said rotor and having radial magnetization, said rotor co-operating with a stator so as to define an air gap, said rotor and said stator being defined by poles, wherein flux produced by said permanent magnets propagates within the rotor along a first magnetic path F3 situated between said poles, said first magnetic path F3 having a reluctance lying in the range 0.5 times to 10 times the reluctance offered to the flux produced by said permanent magnets and propagating via said air gap.

Abstract: A motor having flux-concentrating permanent magnets, the motor including a stator with windings and a rotor including a shaft, a sleeve surrounding the shaft for holding rotor laminations, and permanent magnets. The motor being characterized in that said sleeve is constituted by unitary sleeves (2) separated by disks (5), the sleeves and the disks being clamped together by tie bars (6) connected to at least one end cheek plate (7) which is fixed to the shaft (1).