Abstract: A handheld electronic device includes a case, an electronic unit and a cooling fan. The case includes at least one rib, an air inlet and a heat outlet. The at least one rib delimits a heat chamber. The air inlet and the heat outlet intercommunicate with an outside of the case. The electronic unit includes a heat source located in the heat chamber. The cooling fan is located in the heat chamber and includes an air entrance and an air exit. The air entrance intercommunicates with the air inlet of the case, and the air exit intercommunicates with the heat outlet of the case.

Abstract: A handheld electronic device includes a case, an electronic unit and a cooling fan. The case includes at least one rib, an air inlet and a heat outlet. The at least one rib delimits a heat chamber. The air inlet and the heat outlet intercommunicate with an outside of the case. The electronic unit includes a heat source located in the heat chamber. The cooling fan is located in the heat chamber and includes an air entrance and an air exit. The air entrance intercommunicates with the air inlet of the case, and the air exit intercommunicates with the heat outlet of the case.

Abstract: A radial-winding stator of a motor including a core and eight poles is disclosed. Each pole has a magnetic pole and a pole piece. The magnetic pole is connected to the core and extends outwards from the core in a radial direction. The pole piece is formed at one end of the magnetic pole distant to the core. The pole piece includes a magnetic end face having an arc length along a circumferential direction of the core, as well as an axial height along an axial direction perpendicular to the radial direction. A ratio of the arc length to the axial height is between 2.05 and 10. In another embodiment, the radial-winding stator includes ten or twelve poles.

Abstract: A motor includes: a base having a shaft tube with a first opening and a second opening at two opposite ends respectively, with a bearing received in the shaft tube; a stator coupled with the base; a rotor having a shaft and a hub, the shaft extending through the first opening and coupling with the bearing, the hub coupling with the shaft and having a through hole for a positioning tool to insert, and the hub further having a permanent magnet, with a gap formed between the permanent magnet and the stator; and a bottom lid coupling with the shaft tube and covering the second opening.

Abstract: A radial-winding stator of a motor including a core and eight poles is disclosed. Each pole has a magnetic pole and a pole piece. The magnetic pole is connected to the core and extends outwards from the core in a radial direction. The pole piece is formed at one end of the magnetic pole distant to the core. The pole piece includes a magnetic end face having an arc length along a circumferential direction of the core, as well as an axial height along an axial direction perpendicular to the radial direction. A ratio of the arc length to the axial height is between 2.05 and 10. In another embodiment, the radial-winding stator includes ten or twelve poles.