Rotor and motor having the same

A motor comprising:

• a rotating shaft;
• a rotor through which the rotating shaft passes;
• and
• a stator disposed at an outside of the rotor, wherein the rotor includes:
• a first rotor core and a second rotor core that are axially stacked;
• the first rotor core includes a first core body and a first teeth protruding from an outer circumferential surface of the first core body;
• and
• the second rotor core includes a second core body and a second teeth protruding from an outer circumferential surface of the second core body,
• wherein each of the first teeth includes a first extension protruding axially in a first direction past a first surface of the first core body, and each of the second teeth includes a second extension protruding axially in a second direction opposite the first direction past a first surface of the second core body,
• wherein the first extension includes a first protrusion provided on a first inner circumferential surface of the first extension,
• wherein the second extension includes a second protrusion provided on a second inner circumferential surface of the second extension,
• wherein the first protrusion includes a third inner circumferential surface of the first protrusion,
• wherein the second protrusion includes a fourth inner circumferential surface of the second protrusion,
• wherein a distance from a center of the second core body to the third inner circumferential surface of the first protrusion is a first radial distance, a distance from a center of the first core body to the second inner circumferential surface of the second extension is a second radial distance, and the first radial distance is less than the second radial distance,
• wherein a distance from the center of the first core body to the fourth inner circumferential surface of the second protrusion is a third radial distance, a distance from the center of the second core body to the first inner circumferential surface of the first extension is a fourth radial distance, and the third radial distance is less than the fourth radial distance.