Abstract: A fan includes a fan frame and an impeller. The fan frame has a housing, a base and at least one supporting element. The inner wall of the housing has at least one guiding portion for increasing an airflow intake of the fan, and the base is disposed within the housing and has a bottom portion and a pressurizing portion. The pressurizing portion is disposed around the bottom portion for increasing an air pressure of the fan. The supporting elements are connected to the housing and the pressurized portion of the base. The impeller is disposed within the housing and supported by the base.

Abstract: A passive heat-dissipating fan system comprises an air-providing device, a cold-end passive heat-dissipating assembly, a hot-end passive heat-dissipating assembly, a separation device capable of guiding airflow to the cold-end and hot-end passive heat-dissipating assemblies, and a cooling device which is disposed in the separation device and has cold and hot ends. When the airflow from the air-providing device passes through the separation device and cooling device, airflow from the air-providing device is separated and then partially directed to the cold-end passive heat-dissipating assembly and partially directed to the hot-end passive heat-dissipating assembly respectively, expelling the heated airflow to an exterior of an electronic system.

Abstract: A brushless DC motor and a stator thereof. The stator comprises an upper magnetic pole piece and a lower magnetic pole piece. The upper magnetic pole piece comprises a plurality of upper protruding portions extending toward the lower magnetic pole piece, and the lower magnetic pole piece comprises a plurality of lower protruding portions extending toward the upper magnetic pole piece. The upper protruding portions and the lower protruding portions are substantially spaced apart and alternately arranged. A positioning portion extending from a distal end of each upper protruding portion is located below the magnetic ring of the rotor, to increase the magnetic force therebetween. Alternatively, a positioning portion can be formed between the lower protruding portions of the lower magnetic pole piece and extended to the bottom of the rotor; thus, an axial attraction force can be generated to stabilize the rotor.

Abstract: A current control device for a fan motor includes a current sampling module, a signal generating module, a current detecting module and a current controlling module. The current sampling module samples an operating current of the fan motor to generate a sampled current signal. The operating current is controlled according to a driving signal. The signal generating module generates a threshold current signal. The current detecting module receives the sampled current signal and the threshold current signal and generates a motor protecting signal according to the sampled current signal and the threshold current signal. The current controlling module receives the motor protecting signal and stops generating or decreases the driving signal according to the motor protecting signal.

Abstract: A fan housing and a fan have stationary blades for guiding airflow. Each stationary blade has at least one airflow-guiding element extending therefrom along the circumference of the fan. The side wall of the airflow-guiding element changes the direction of the airflow so that the airflow at the outlet is fully introduced toward the heat source. Furthermore, the airflow-guiding element regulates the airflow, restrains the turbulent flow at the outlet and on the curved surface of the stationary blade, decreases the noise arising from the turbulent flow, and prevents foreign matter from entering the fan housing so as to protect the inside elements thereof.

Abstract: A fan includes a fan housing and an impeller. The fan housing includes a frame, a base disposed in the frame, a plurality of stationary blades disposed between the frame and the base, and a plurality of airflow-guiding elements extending inward from the frame and toward the base. The airflow-guiding elements and the stationary blades are alternately arranged. The impeller is disposed in the fan housing.

Abstract: A permanent magnet (PM) stepping motor includes a rotor structure and a stator. The rotor structure includes an axis, multipolar yoke stacks, and at least one spacer. Each of multipolar yoke stacks includes an N multipolar yoke, a permanent magnet and an S multipolar yoke combined as a hamburger-like structure, and each N pole of the N multipolar yoke and each S pole of the S multipolar yoke are alternately aligned. One of the spacer is sandwiched between each pair of the multipolar yoke stacks. The stator circumnavigates the axis and the multipolar yoke stacks, and provides a magnetic field for the multipolar yoke stacks to make the axis rotating. This PM stepping motor has the advantage of a minimized magnetic pole pitch and a high torque, which cannot be achieved in conventional stepping motors.

Abstract: The invention provides a motor driving device including a converter receiving and converting a non-electrical power source, such as light, heat, mechanical or chemical energy, to a first electrical power, and a selector electrically connected between the converter and a motor, for receiving the first electrical power and a second electrical power from a power source, such as an electrical power generator, and outputting the first or second electrical power according to a rotation speed of the motor.

Abstract: A method of manufacturing a dynamic bearing comprises providing a bearing having a through hole. A photoresist is coated on an inner wall of the through hole. An ultraviolet lamp capable of inserting into the through hole is provided. A mask having patterns of pressure-generating grooves is attached to the surface of the ultraviolet lamp. The ultraviolet lamp is inserted into the through hole to perform an exposure process with the mask. The exposed portions of photoresist are developed to appear portions of the inner wall underneath. The appeared portions of the inner wall are etched to form grooves on the bearing, and finally, the photoresist remaining on the inner wall of the through hole is stripped.

Abstract: A dynamic bearing manufacturing method including steps as follow. A plate is provided and a plurality of grooves is formed on a surface of the plate. The plate formed with grooves is rolled into a hollow cylinder. The grooves are located on the inner surface of the hollow cylinder, and thus to reduce cost of manufacturing process.

Abstract: A fan includes a frame and an impeller. The impeller is disposed in the frame and the impeller has a plurality of blades. Each blade has a wing part and a flap part, and the wing part and the flap part form a predetermined angle. A blade is also disclosed.

Abstract: A passive fan assembly includes an impeller and a plurality of guide blades disposed in front of the impeller. The impeller includes a plurality of blades extending at about 90 degrees relative to the guide blades. Thus, when airflow enters the passive fan assembly, the guide blades guide the airflow to effectively impact on blades of the impeller.

Abstract: This specification discloses a heat sink for coolers. The heat sink contains a heat conductive element, a heat dissipating shell covering over the heat conductive element, and a plurality of heat dissipating fins installed on the heat dissipating shell. The heat conductive element is comprised of a heat conductive plate and a heat conductive block installed at the center thereof. The area of the lower surface of the heat conductive block is greater than that of the upper surface thereof. When the lower surface of the heat conductive plate is in contact with a device that needs heat dissipation, the heat conductive block increases the heat conducting volume at the center of the heat conductive plate, so that the heat produced by the device can be released at an optimal rate.

Abstract: A winding method of a motor stator comprises the steps of serially winding a wire on a plurality of odd poles along a first direction; pulling out a common terminal from the wire to serve as a first power terminal; serially winding the wire on a plurality of even poles along a second direction; and knotting a start and an end of the wire to form a second power terminal. A single-phase motor comprises a stator and a rotor. The stator has a plurality of poles and a wire, and the rotor cooperates with the stator. The wire serially winds odd poles of the plurality of poles along a first direction and then serially winds even poles of the plurality of poles along a second direction.

Abstract: A driving apparatus for fan motors, electrically connected between a pulse width modulation (PWM) signal generator and a controller, includes a converter electrically connected to the PWM signal generator, generating a first reference voltage according to the duty cycle of a PWM signal generated by the PWM signal generator; a reference voltage generator electrically connected to an external power source, generating a second reference voltage according to the external power source; and a comparator having a first and second input terminal and an output terminal; wherein the first input terminal is electrically connected to the converter, the second input terminal is connected to the reference voltage generator and the output terminal is connected to the controller, and when the first reference voltage is greater than the second reference voltage, a driving signal is output from the output terminal to the controller to control the rotation speed of the fan motor.

Abstract: A dual motor structure of a dual fan includes a first stator structure, a first rotor structure, a first bearing, a second stator structure, a second rotor structure and a second bearing. The first stator structure has a first bearing tube. The first rotor structure has a first shaft inserted into the first bearing tube. The first bearing is telescope onto the first shaft, and is mounted in the first bearing tube. The second stator structure has a second bearing tube. The second rotor structure has a second shaft inserted into the second bearing tube. The second bearing is telescope onto the second shaft, and is mounted in the second bearing tube. The first shaft is postioned corresponding to the second shaft to generate a magnetic interaction therebetween.

Abstract: A power monitoring apparatus of a fan is for receiving an input voltage from external. The power monitoring apparatus includes a starting unit and a voltage detecting unit. The starting unit receives the input voltage and starts the fan according to the input voltage. The voltage detecting unit is electrically connected to the starting unit and generates a warning signal when the input voltage is not equal to a reference value.

Abstract: A motor control method and device. The motor control device includes a programmable integrated circuit (IC) receiving a phase signal, the phase of which is consistent with the rotation phase of a coil of the motor. The programmable IC generates a duty-cycle signal in accordance with the period of the phase signal. The duty-cycle signal comprises a rising segment and a falling segment and when the phase signal changes phase, the duty cycle represented by the duty-cycle signal is a first duty cycle, allowing the input power of the motor remain at a minimum. The duty-cycle signal is input to the coil, controlling the coil on and off and, thereby rotating the motor.

Abstract: An under voltage protection device is for cooperating with a fan. The under voltage protection device includes a voltage detective unit and a starting unit. The voltage detective unit is for receiving an input voltage and a reference voltage. The starting unit is electrically connected to the voltage detective unit and the fan, and starts the fan according to the input voltage. The voltage detective unit shuts the starting unit down if the input voltage is lower than the reference voltage.