A rotor comprising: a rotor core; a cover disposed above the rotor core, the cover being an annular plate shaped cover with a central opening which is axially arranged on one side of the rotor core; magnets disposed on an outer circumferential surface of the rotor core; and a can member which accommodates the rotor core and the magnet and is combined with the cover, wherein the cover comprises a plurality of guides extending downward, the guides being inserted axially between the magnets which are adjacent to each other, wherein the guides are arranged on the outer circumferential surface of the rotor core and arranged inside the can member, wherein the can member comprises at least one protrusion portion in a quadrangular shape which protrudes from an edge and is combined with the cover, the protrusion portion being combined with the cover and fixing the can member to the rotor core, the protrusion portion being formed axially on an edge of a top and of a cylindrical body of the can member, wherein the cover comprises a stopper and a cover body including an annular inner portion and an annular outer portion formed outside the inner portion, wherein the protrusion portion is formed to be bent along the outer portion and be combined with the cover, wherein the outer portion is formed to be higher than the inner portion on the basis of an axial direction of the rotor core, wherein the height of the inner portion of the cover body is formed to be lower than the height of the outer portion, wherein the top surface of the outer portion includes an inclined surface which is formed to be inclined toward a center of the rotor core, so that an outside of the outer portion forms a step portion on which the protrusion portion can move, an inside of the outer portion being configured to be connected to the inner portion through the inclined surface, wherein the stopper includes a column portion and a fixing portion, the column portion protruding from a top surface of the inner portion of the cover, the column portion being formed to be vertical to the top surface of the inner portion, the fixing portion being formed to extend horizontally from a fore end of the column portion, the fixing portion being disposed while being spaced apart from a top surface of the cover, and wherein the length of the bottom surface of the fixing portion is formed to be longer than the length of the top surface of the fixing portion, so that in an outward direction, the position of a fore end of the fixing portion is located farther out than the position of a fore end of the protrusion portion on a basis of a radial direction of the cover, wherein the fore end of the fixing portion is formed to tilt so that it induces an end of the protrusion portion to slide on the fore end of the fixing portion and be located below the fixing portion. a rotor core; a cover disposed above the rotor core, the cover being an annular plate shaped cover with a central opening which is axially arranged on one side of the rotor core; magnets disposed on an outer circumferential surface of the rotor core; and a can member which accommodates the rotor core and the magnet and is combined with the cover, wherein the cover comprises a plurality of guides extending downward, the guides being inserted axially between the magnets which are adjacent to each other, wherein the guides are arranged on the outer circumferential surface of the rotor core and arranged inside the can member, wherein the can member comprises at least one protrusion portion in a quadrangular shape which protrudes from an edge and is combined with the cover, the protrusion portion being combined with the cover and fixing the can member to the rotor core, the protrusion portion being formed axially on an edge of a top and of a cylindrical body of the can member, wherein the cover comprises a stopper and a cover body including an annular inner portion and an annular outer portion formed outside the inner portion, wherein the protrusion portion is formed to be bent along the outer portion and be combined with the cover, wherein the outer portion is formed to be higher than the inner portion on the basis of an axial direction of the rotor core, wherein the height of the inner portion of the cover body is formed to be lower than the height of the outer portion, wherein the top surface of the outer portion includes an inclined surface which is formed to be inclined toward a center of the rotor core, so that an outside of the outer portion forms a step portion on which the protrusion portion can move, an inside of the outer portion being configured to be connected to the inner portion through the inclined surface, wherein the stopper includes a column portion and a fixing portion, the column portion protruding from a top surface of the inner portion of the cover, the column portion being formed to be vertical to the top surface of the inner portion, the fixing portion being formed to extend horizontally from a fore end of the column portion, the fixing portion being disposed while being spaced apart from a top surface of the cover, and wherein the length of the bottom surface of the fixing portion is formed to be longer than the length of the top surface of the fixing portion, so that in an outward direction, the position of a fore end of the fixing portion is located farther out than the position of a fore end of the protrusion portion on a basis of a radial direction of the cover, wherein the fore end of the fixing portion is formed to tilt so that it induces an end of the protrusion portion to slide on the fore end of the fixing portion and be located below the fixing portion.