Armature of motor, manufacturing method of the same and motor using the same and motor having the same

A motor armature comprising:

• a plurality of pole pieces each comprising a coil wound around a rod formed of a magnetic material;
• an inner cylinder formed of a magnetic material and having an outer peripheral surface fixed to a first end of the plurality of pole pieces so that the pole pieces are disposed radially at equal intervals outside the inner cylinder;
• and
• an outer cylinder fixed to a second end of each of the pole pieces so that the pole pieces are disposed radially at equal intervals to an inner peripheral surface of the outer cylinder, each cylinder being comprised of a hoop member made of a magnetic material curled into a cylinder, and the rod being comprised of a wire piece formed by cutting a wire made of a magnetic material.

A motor armature, comprising:

• a plurality of pole pieces each comprising a coil wound around a rod formed of a magnetic material;
• and
• a cylinder made of a magnetic material fixed to the plurality of pole pieces so that the pole pieces are disposed radially at equal intervals at a position distant from the center of the cylinder by a predetermined distance on at least one of an inner and outer peripheral surface of the cylinder;
• wherein the rod of each of the pole pieces comprises an inner core formed of a magnetic material having a high saturation magnetic flux density and a skin layer formed around the inner core comprising a magnetic material having a lower saturation magnetic flux density than the core and having higher magnetic permeability than the core.

A motor armature comprising:

• a plurality of pole pieces each comprising a coil wound around a rod formed of a magnetic material;
• an inner cylinder formed of a magnetic material and having an outer peripheral surface fixed to a first end of the plurality of pole pieces so that the pole pieces are disposed radially at equal intervals outside the inner cylinder;
• and
• an outer cylinder fixed to a second end of each of the pole pieces so that the pole pieces are disposed radially at equal intervals to an inner peripheral surface of the outer cylinder, wherein the rod of each of the pole pieces comprises an inner core formed of a magnetic material having a high saturation magnetic flux density and a skin layer formed around the inner core comprising a magnetic material having a lower saturation magnetic flux density than the core and having higher magnetic permeability than the core.