Abstract: A fan system includes a stator magnetic pole, a driving unit and a real-time stopping unit. The driving unit is coupled with the stator magnetic pole and controls a polarity change of the stator magnetic pole in accordance with a driving signal. The real-time stopping unit is electrically connected with the driving unit. When the fan system is powered off, the driving unit enables two ends of the stator magnetic pole to have the same voltage level in accordance with a control signal generated by the real-time stopping unit so that the fan system stops operating immediately.

Abstract: A heat-dissipating fan with a plurality of upward rotor blades is provided. The heat-dissipating fan includes a housing, an impeller having a hub and a plurality of rotor blades disposed around the hub, and a base disposed inside the housing for supporting the impeller thereon. The rotor blades have at least one inclined edge with a first inclined angle relative to the horizontal line perpendicular to the axis of the heat-dissipating fan, respectively.

Abstract: A fan speed control circuit includes a pulse width modulation (PWM) signal generating circuit, a driving circuit and a phase compensation unit. The PWM signal generating circuit generates a PWM control signal with a sequence of alternating on-time and off-time, and the driving circuit outputs a driving signal according to the PWM control signal to a fan motor. The phase compensation unit is connected to the fan motor for delaying or advancing the PWM control signal by a phase angle to synchronize the acting period of the back electromotive force formed by the magnetic flux variation with the off-time of the PWM control signal. The present invention further provides a bi-power motor driving system including a motor rotating by receiving a first power from a first power generator, and a driving circuit for driving the motor according to a second power from a second power generator.

Abstract: A fan speed control device includes a controller, a switch and a voltage regulator. The controller detects a rotation speed signal of the fan to generate a first driving signal when the rotation speed signal is relatively higher than a predetermined rotation speed signal and generates the first driving signal and a second driving signal when the rotation speed signal is relatively lower than the predetermined rotation speed signal. The switch is electrically connected with the controller and receives the first driving signal. The voltage regulator, which is electrically connected with the controller, the switch and the fan, receives the second driving signal, and controls the rotation speed of the fan in accordance with the first driving signal and the second driving signal.

Abstract: A control system for a motor. The control system and the motor receive an external power. The control system comprises a driver and a switch device. The driver is electrically connected to the motor. The switch device is electrically connected between the external power and the driver and turned on or off according to a control signal. The driver drives the motor according to the external power when the switch device is turned on.

Abstract: A fan system and a stopping method for the fan system are provided. The fan system is electrically connected to a power supply and receives the power therefrom. The fan system includes an energy storage apparatus, a motor and a start-up device. The energy storage apparatus receives and stores the power. The motor is electrically connected to the energy storage apparatus and receives the power. The driver is coupled between the energy storage apparatus and the motor to form a control path and generates a driving signal to the motor according to received power. The start-up device is coupled between the energy storage apparatus and the motor to form a power path therewith. When no power is provided to the fan system, the energy storage apparatus releases the stored power and the start-up device generates a start-up signal to the motor in accordance with the released power so as to form a short-circuit loop in the motor to stop the motor.

Abstract: A serial fan includes a frame, a plurality of rotor vanes, a support connected to the frame through a plurality of connecting parts. The plurality of rotor vanes are arranged in series in the frame along an axial direction and the plurality of connecting parts are disposed therebetween to minimize space occupied by the serial fan in the axial direction, and effectively increase the blast pressure.

Abstract: A fan comprises an impeller and a motor. The impeller has a hub, a plurality of blades and a plurality of reinforced elements. The blades are disposed around the hub. At least one reinforced element is disposed on the active surfaces of two adjacent blades. The blades and the reinforced elements are integrally formed as a single piece. The motor connects to the impeller for driving it to rotate.

Abstract: A stator structure includes a first cover, a stator assembly and a filler. The first cover has an accommodation space for accommodating the stator assembly therein. The filler is applied between the first cover and the stator assembly to surround the stator assembly. A manufacturing method of the stator structure is also disclosed.

Abstract: A heat dissipation apparatus. A fan frame includes an air inlet, an air outlet, a passage, and a curved expansion portion. The air inlet is opposite the air outlet. The passage is between the air inlet and the air outlet, guiding airflow from the air inlet to the air outlet. The curved expansion portion is radially and outwardly extended from an inner peripheral wall of the passage at the air inlet or air outlet. An impeller is disposed in the fan frame and includes a plurality of blades. Each blade is disposed in the passage and includes an extension end extending to the curved expansion portion.

Abstract: The present invention provides an instantaneous fan stopping method and structure thereof. The method and structure can eliminate the inertial rotating state of the fan when the power supplied to the fan is cut off. In accordance with the present invention, a closed circuit is formed between the two terminals of the coil used to drive the fan. When the closed circuit is formed, the inertial rotation of the fan can generate an induced current in this coil, which, in turn, generates a magnetic force to stop the fan.

Abstract: A fan system for receiving an input voltage from exterior includes a first fan module, a second fan module and a seriate starting module. The seriate starting module is electrically connected with the first fan module and the second fan module. The seriate starting module receives the input voltage and starts the first fan module according to the input voltage, and starts the second fan module according to the input voltage after the first fan module is started for a predetermined time.

Abstract: An impeller includes a hub and a plurality of blades disposed around an outer wall of the hub. Each of the blades has a leading edge with a predetermined distance below the top of the hub and a trailing edge protruding from the bottom of the hub. A fan including the impeller is also provided.

Abstract: A fan system includes a fan module, a starting module, a temperature-sensing element and a controlling module. The starting module is electrically connected with the fan module for starting it. The temperature-sensing element generates a sensing signal in accordance with an ambient temperature. The controlling module receives the sensing signal for controlling the starting module. When the ambient temperature is higher than a first temperature or is lower than a second temperature, the controlling module controls the starting module to disable the fan module.

Abstract: A fan system is electrically connected to a power supply and receives a power generated from the power supply. The fan system includes at least one fan, a driving circuit, at least one protecting device, and a protecting circuit. The driving circuit is electrically connected to the fan and receives the power to drive the fan. The protecting device is electrically connected with the fan, and the protecting circuit is electrically connected between the protecting device and the driving circuit. When one fan is short-circuited, the protecting circuit outputs a current value larger than a current-limited value of the protecting device. Also, a method for protecting a fan system is disclosed.

Abstract: A fan of the present invention includes a fan housing and an impeller disposed in the fan housing. The fan housing includes a plurality of connecting elements at its air outlet. Each connecting element includes a plurality of air-guiding teeth thereon, which can guide the air to flow smoothly out from the fan housing so as to increase airflow and air pressure, and reduce the noise.

Abstract: A centrifugal fan, comprising a frame and a first guide portion. The frame comprises a bottom portion and a curved wall connected thereto. The curved wall comprises an airflow inlet. The first guide portion disposed along the curved wall at the bottom portion comprises a beginning area, a middle area, and an ending area. The middle area connects the beginning and the ending areas, and the beginning area extends from the airflow inlet. The beginning area has a width less than that of the ending area, and the beginning area has a height greater than that of the ending area.

Abstract: An impeller applied to a centrigal fan includes a base plate, a hub and a plurality of first blades. The hub is connected to the base plate and the first blades are disposed on the base plate with respect to the hub as a center. Furthermore, the hub has a plurality of second blades disposed around its outer wall to enhance its performance. A centrifugal fan including the impeller is also disclosed.

Abstract: A centrifugal fan. A hub covers a driving device. An impeller surrounds the hub and includes a first blade set and a second blade set. The first blade set surrounds the hub and includes a first combining portion, a second combining portion, and a plurality of first blades. The first and second combining portions are respectively connected to the first blades. The second blade set includes a third combining portion, a fourth combining portion, and a plurality of second blades. The third and fourth combining portions are respectively connected to the second blades. The first blade set is assembled with the second blade set by assembling the first combining portion with the third combining portion and assembling the second combining portion with the fourth combining portion.

Abstract: A fan system, which receives an input voltage from exterior, includes a first fan module, a second fan module, a first starting module, a second starting module, a temperature-sensing element and a first controlling module. The first starting module receives the input voltage and starts the first fan module. The second starting module, which is electrically connected to the second fan module, receives the input voltage. The temperature-sensing element produces a sensing signal in accordance with an ambient temperature. The first controlling module controls the second starting module in accordance with the sensing signal so as to start the second fan module.