Abstract: A stator includes a stator core, two insulation frames, and a plurality of coils. The stator core includes a plurality of yokes stacked one on the other along an axial direction of the stator core. The stator core has a larger outer size at one end thereof than the other end thereof. The insulation frames respectively cover the one end and the other end of the stator core. Each coils wounds around the insulation frames and corresponding portions of the stack of yoke. Each of the yokes includes an annular plate and a plurality of arms extending outwardly from an outer periphery of the annular plate, outer edges of the arms of each yoke are located on a same imaginary circle which has a common center with the annular plate, and diameters of the imaginary circles of the yokes are different from each other.

Abstract: An exemplary heat dissipation fan includes a rotor and a stator. The rotor includes a hub, a central shaft extending down from a top end of the hub, the shaft having a free end far from the top end of the hub. A magnetic element attached to an inner periphery of the hub. The stator includes a stator core consisting layers of yokes, two insulation frames mounted at two opposite ends of the stator core and a coil wound around the insulation frames. An outer surface of the stator faces and is spaced from an inner surface of the magnetic element of the rotor with a clearance defined therebetween. A width of a bottom end of the clearance adjacent to the free end of the shaft being smaller than a width of a top end of the clearance.

Abstract: A charging battery unit includes a receiving unit and a battery. The receiving unit includes a fixing member and a coil fixed on the fixing member. The coil receives external electromagnetic signals to generate induction currents. The battery is electrically connected to the coil and receives the induction currents generated by the coil. The present disclosure also relates an electronic device with the charging battery unit.

Abstract: The present disclose relates to a wireless charging device for charging a portable electronic device. The wireless charging device includes a charging panel, a transmitting unit and a heat dissipation unit. The charging panel includes a first surface and a second surface opposite to the first surface, the first surface supports the portable electronic device, and the portable electronic device includes a top surface away from the charging panel. The transmitting unit includes a coil for generating electromagnetic signals for charging the portable electronic device. The heat dissipation unit includes a base and a pressing portion connected to the base. The base thermally contacts the second surface of the charging panel, and the pressing portion thermally contacts the top surface of the portable electronic device.

Abstract: A wire arrangement mechanism including a guiding slot and an arranging slot is formed on a fan frame. The guiding slot includes a bottom wall and two holding walls extending therefrom. The arranging slot is defined by an outer frame and a confining portion connected thereto. The arranging slot is staggered from and communicated with the guiding slot.

Abstract: An exemplary heat dissipation fan includes a rotor and a stator. The stator includes a stator core. The rotor is rotatably mounted around the stator. The rotor includes a hub and a magnet ring received in the hub. The hub includes a top wall and a peripheral side wall depending from the top wall. The magnet ring is attached to the side wall and surrounding the stator. The magnet ring has a larger thickness as measured in a radial direction at a first end which is far away from the top wall than a second end which is adjacent to top wall, such that an attracting force formed between the first end of the magnet ring and the stator core is larger than that formed between the second end of the magnet ring and the stator core.

Abstract: A cooling fan includes a fan housing and a rotor received in the fan housing. The fan housing has an air inlet and an outlet opposite to the air inlet. The rotor includes a shaft, a hub engaged with the shaft, and a plurality of rotary blades extending outwardly from the hub. The hub has an outer surface expanding along a direction parallel to a central axis of the shaft from the air inlet to the air outlet.

Abstract: An exemplary heat dissipation fan includes a rotor and a stator. The stator includes a stator core. The rotor is rotatably mounted around the stator. The rotor includes a hub and a magnet ring received in the hub. The hub includes a top wall and a peripheral side wall depending from the top wall. The magnet ring is attached to the side wall and surrounding the stator. The magnet ring has a larger thickness as measured in a radial direction at a first end which is far away from the top wall than a second end which is adjacent to top wall, such that an attracting force formed between the first end of the magnet ring and the stator core is larger than that formed between the second end of the magnet ring and the stator core.

Abstract: An exemplary heat dissipation fan includes a rotor and a stator. The rotor includes a hub, a central shaft extending down from a top end of the hub, the shaft having a free end far from the top end of the hub. A magnetic element attached to an inner periphery of the hub. The stator includes a stator core consisting layers of yokes, two insulation frames mounted at two opposite ends of the stator core and a coil wound around the insulation frames. An outer surface of the stator faces and is spaced from an inner surface of the magnetic element of the rotor with a clearance defined therebetween. A width of a bottom end of the clearance adjacent to the free end of the shaft being smaller than a width of a top end of the clearance.

Abstract: A cooling fan includes a fan housing, a stator and a rotor received in the fan housing. The rotor includes a shaft, a hub engaged with the shaft, a plurality of rotary blades extending outwardly from the hub, a connecting member and a magnet mounted in the connecting member. The hub includes a plurality of hooks. The connecting member has a flange clasping the hooks of the hub to mount the magnet in the hub.

Abstract: An oil sealing structure of a motor includes a cover and at least one sealing element. The motor has a shaft, a fluid bearing and a bushing. The fluid bearing mounts to the shaft and is accommodated in the bushing. The cover is disposed around the shaft and is connected with an opening of the bushing. The sealing element is disposed around the shaft and between the fluid bearing and the cover. A fan and a motor including the above-mentioned oil sealing structure are also disclosed.

Abstract: An exemplary sleeve bearing system includes a bearing housing, a sleeve bearing and a resilient washer. The bearing housing defines a receiving hole therein. The receiving hole has a first diameter. The sleeve bearing has a second diameter which is slightly less than the first diameter, and the sleeve bearing is received in the receiving hole of the bearing housing. The resilient washer is received in the receiving hole of the bearing housing and is fitted around the sleeve bearing. The resilient washer is sandwiched between the bearing housing and the sleeve bearing and resiliently abuts an outer circumferential surface of the sleeve bearing to thereby mount the sleeve bearing in the receiving hole of the bearing housing.

Abstract: A cooling fan includes a fan housing and a stator and an impeller received in the fan housing. The fan housing includes a frame and a mounting portion located in the frame. The stator is received in the frame and mounted to the mounting portion. The impeller is mounted to the stator and rotatable with respect to the stator. The impeller includes a hub and a plurality of blades extending radially and outwardly from the hub. Each of the blades includes an inner end connected with the hub and an outer end distant from the hub. Each of the blades forms a tab on the outer end at the end surface.

Abstract: An electronic device includes a casing, a centrifugal blower and sidewall received in the casing. The casing is adapted for accommodating electronic components therein, and includes a bottom cover and an opposite top cover. The centrifugal blower is surrounded by the sidewall and includes a sleeve directly mounted to the bottom cover, a bearing member mounted in the sleeve, a stator mounted to the sleeve and an impeller rotatably supported by the bearing member. The bottom cover of the electronic device functions as a bottom plate of the centrifugal blower.

Abstract: A motor control device includes a rotation speed control circuit, a voltage transforming circuit, a buffering circuit and a driving circuit. The rotation speed control circuit provides a rotation speed control signal. The voltage transforming circuit is electrically connected to the rotation speed control circuit and transforms the rotation speed control signal to a speed control voltage signal. The buffering circuit, electrically connected to the voltage transforming circuit, receives the speed control voltage signal and delays or buffers output of the speed control voltage signal. The driving circuit, electrically connected to the buffering circuit, receives the speed control voltage signal from the buffering circuit and generates a driving signal according to the speed control voltage signal so as to control the operation of the motor.

Abstract: A dynamic bearing manufacturing includes steps of: providing a bearing and a processing tool, the bearing having an axial hole, and the processing tool having at least one protruding pattern formed on an exterior wall of the processing tool; positioning the processing tool into the axial hole of the bearing; pressing the processing tool to contact with an inner wall of the bearing so as to transfer and print the protruding pattern of the processing tool onto the inner wall of the bearing; rotating the processing tool at a first rotation speed and driving the bearing to rotate at a second rotation speed; and forming at least one concave pattern on the inner wall of the bearing, and the at least one concave pattern being corresponding to the protruding pattern of the processing tool.

Abstract: An electronic device includes a casing, a centrifugal blower and sidewall received in the casing. The casing is adapted for accommodating electronic components therein, and includes a bottom cover and an opposite top cover. The centrifugal blower is surrounded by the sidewall and includes a sleeve directly mounted to the bottom cover, a bearing member mounted in the sleeve, a stator mounted to the sleeve and an impeller rotatably supported by the bearing member. The bottom cover of the electronic device functions as a bottom plate of the centrifugal blower.

Abstract: A cooling fan includes a fan housing and a stator and an impeller received in the fan housing. The fan housing includes a frame and a mounting portion located in the frame. The stator is received in the frame and mounted to the mounting portion. The impeller is mounted to the stator and rotatable with respect to the stator. The impeller includes a hub and a plurality of blades extending radially and outwardly from the hub. Each of the blades includes an inner end connected with the hub and an outer end distant from the hub. Each of the blades forms a tab on the outer end at the end surface.

Abstract: A sleeve bearing system includes a bearing housing, a sleeve bearing received in the bearing housing, and a wear-resistant pad received at a bottom of the bearing housing. The bearing housing defines a receiving recess therein for receiving the sleeve bearing. The wear-resistant pad is sandwiched between the sleeve bearing and a bottom of the bearing housing. The wear-resistant pad includes a central supporting portion aligning with the bearing hole of the sleeve bearing and a plurality of ears extending radially and outwardly from and an outer periphery of the supporting portion. A reservoir is defined between adjacent ears around the supporting portion.

Abstract: An exemplary sleeve bearing system includes a bearing housing, a sleeve bearing and a resilient washer. The bearing housing defines a receiving hole therein. The receiving hole has a first diameter. The sleeve bearing has a second diameter which is slightly less than the first diameter, and the sleeve bearing is received in the receiving hole of the bearing housing. The resilient washer is received in the receiving hole of the bearing housing and is fitted around the sleeve bearing. The resilient washer is sandwiched between the bearing housing and the sleeve bearing and resiliently abuts an outer circumferential surface of the sleeve bearing to thereby mount the sleeve bearing in the receiving hole of the bearing housing.