US Patent 10581288 Rotor and rotary electrical machine

A rotor includes: a rotary member; permanent magnets in a plurality of columns which are arranged along the circumferential direction of the rotary member and each of which is divided into a plurality of permanent magnets in a rotary axis direction X of the rotary member; and a sheath tube which is fitted to the outer circumferential side of the permanent magnets, which covers the permanent magnets and which is formed of a fiber-reinforced plastic, and the sheath tube is divided, in the rotary axis direction X of the rotary member, by a division number which exceeds the division number of the permanent magnets.