Abstract: An electric motor includes a stator having multiple magnetic poles and a rotor rotatably mounted to the stator. The rotor includes a shaft, a commutator and a rotor core fixed to the shaft; and windings wound on the rotor core and electrically connected to the commutator. The rotor core is formed by stacking a plurality of laminations. Each lamination includes an inner ring having a hole for fixing the shaft; an outer ring radially spaced from the inner ring; multiple teeth extending outwardly from the outer ring, and multiple ribs connecting the inner ring to the outer ring. Each rib has a width w measured in a circumferential direction of the lamination. The number of ribs is n. The width w and the number n satisfy the formula: 0.75?n×w2?64, where the width w is measured in millimeters.

Abstract: An electric motor includes a stator having multiple magnetic poles and a rotor rotatably mounted to the stator. The rotor includes a shaft, a commutator and a rotor core fixed to the shaft; and windings wound on the rotor core and electrically connected to the commutator. The rotor core is formed by stacking a plurality of laminations. Each lamination includes an inner ring having a hole for fixing the shaft; an outer ring radially spaced from the inner ring; multiple teeth extending outwardly from the outer ring, and multiple ribs connecting the inner ring to the outer ring. Each rib has a width w measured in a circumferential direction of the lamination. The number of ribs is n. The width w and the number n satisfy the formula: 0.75?n×w2?64, where the width w is measured in millimeters.

Abstract: A method for making device housing comprises: providing a transparent film; forming a coating on one surface of the film by printing ink containing metal powder on the film and ultrasonically treating the coating; and molding a substrate onto the coating.

Abstract: A housing comprises a transparent exterior coating, a photoelectric conversion coating bonded with the exterior coating and a substrate molded on the photoelectric conversion coating. The photoelectric conversion coating has electrode contacts thereon. The photoelectric conversion coating is used to convert light energy to electrical energy. The disclosure also describes an electronic device using the housing and a method for making the housing there.

Abstract: A method for making device housing comprises: providing a transparent film; forming a coating on one surface of the film by printing ink containing metal powder on the film and ultrasonically treating the coating; and molding a substrate onto the coating.