Abstract: A modified mounting structure for a heat-dissipating device. The heat-dissipating device has a motor and a seat with a slot mounted on a base or the cover portion of a stator thereof. The seat secures a motor controller of the heat-dissipating device detecting phase changes of the magnetic poles of the motor. The structure of a heat-dissipating device reduces required components, manufacturing cost and assembly time, and the control circuit is greatly simplified.

Abstract: A motor control circuit includes a pulse width modulation (PWM) signal generating circuit, a driving circuit and a waveform-shaping circuit connected between the PWM signal generating circuit and the driving circuit. The PWM signal generating circuit generates a square wave with a sequence of alternating on-time and off-time. The waveform-shaping circuit adjusts the rise-time and the fall-time of the square wave to be both within a range of 5% to 15% of the square wave period, and the driving circuit outputs a driving signal to a fan motor according to the adjusted square wave.

Abstract: A motor control circuit includes a pulse width modulation (PWM) signal generating circuit, a driving circuit and a waveform-shaping circuit connected between the PWM signal generating circuit and the driving circuit. The PWM signal generating circuit generates a square wave with a sequence of alternating on-time and off-time. The waveform-shaping circuit adjusts the rise-time and the fall-time of the square wave to be both within a range of 5% to 15% of the square wave period, and the driving circuit outputs a driving signal to a fan motor according to the adjusted square wave.

Abstract: A fan system is electrically connected with a driving source and includes a first fan, a second fan and an energy storage. The second fan is rotated by the first fan for generating an electric energy. The energy storage is electrically connected with the second fan for storing the electric energy and keep supplying power when the driving source is out of order or the fan is rotating in lower rotation speed.

Abstract: A control device for controlling a motor includes a sensing module, a modifying module and a driving module. The sensing module senses the motor to generate a sensing signal. The modifying module receives the sensing signal and generates a phase modifying signal according to the sensing signal. The driving module receives the phase modifying signal and generates a driving current to drive the motor according to the phase modifying signal.

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 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 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 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.

Abstract: A fan motor speed control circuit is disclosed. The circuit includes a digital/analog converting unit and a driving unit. The digital/analog converting unit takes charge of receiving a pulse width modulation (PWM) signal and converting it into a voltage signal. The driving unit is connected with the digital/analog converting unit in series for receiving the voltage signal, while the driving unit provides a first predetermined voltage level and a second predetermined voltage level as references. The fan motor is kept to run with a low constant rotation speed when the voltage signal level is higher than the first predetermined voltage level, with a full constant rotation speed when the voltage signal level is lower than the second predetermined voltage level, and with a variable rotation speed when the voltage signal level is lower than the first predetermined voltage level and higher than the second predetermined voltage level.

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 control device of a fan system, which has at least one fan, receives a starting voltage. The control device includes a start controlling unit and a driving unit. The start controlling unit receives the starting voltage and outputs a start controlling signal according to the starting voltage. After a predetermined period, the start controlling unit stops sending the start controlling signal. The driving unit is electrically connected to the start controlling unit and the fan, respectively. The driving unit receives the start controlling signal for controlling the rotation speed of the fan.

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 connecting device of a hot swap fan module comprises at least one terminal and a casing. The at least one terminal is electrically connected to the fan so that, when the fan is mounted in a system, electrical connection is formed between the fan and the system. The connecting device further comprises at least one LED (light emitting diode) which is electrically connected to the fan or the at least one terminal for indicating the operating state of the fan, and at least one cover plate protruded from at least one edge of the casing so as to form the whole casing into an L or U-shaped structure. The casing is closely attached to one side face of the fan housing when the casing is assembled to the fan. The casing also has a recess for receiving those lead wires electrically connecting the terminals, the fan, and the LED.

Abstract: A motor control device is used to control a motor to rotate. The motor control device includes a phase-wave signal sampling module, a first waveform modulating module, a second waveform modulating module and a control signal integrating module. The phase-wave signal sampling module outputs a first phase-wave signal and a second phase-wave signal in accordance with the rotation of the motor. The first waveform modulating module generates a first control signal in accordance with the first phase-wave signal. The second waveform modulating module generates a second control signal in accordance with the second phase-wave signal. The control signal integrating module generates a rotation rate control signal in accordance with the first control signal and the second control signal, and inputs the rotation rate control signal to a drive module to control a rotation rate of the motor.

Abstract: A fan control device receives a target revolution signal to control a rotation speed of a fan. The device includes a temperature measuring module, a revolution modulating module and a driving module. The temperature measuring module generates a temperature value according to an ambient temperature of the fan. The revolution modulating module is electrically connected with the temperature measuring module, receives the temperature value, and generates a control signal according to the temperature value and the target revolution signal. The driving module is electrically connected with the revolution modulating module, and generates a driving signal to drive the fan according to the control signal. In addition, a fan control method, which is applied to the fan control device, is also provided.

Abstract: A blower comprises a housing and an impeller. The housing comprises a side outlet and an inlet comprising a predetermined profile, and the impeller is disposed in the housing. The predetermined profile is quadratrical, elliptical, polygonal, non-coaxial circle, or irregularly closed shaped. A flow tunnel is disposed between the impeller and the housing.

Abstract: A motor control circuit and method thereof serving a coil for controlling the motor. The motor control circuit comprises a separated signal generating circuit generating a separated signal and a comparator comparing a first phase signal from a Hall element or a second phase signal from a phase signal generating circuit with the separated signal. Thus, a motor speed control signal is generated to control the motor. The noise is reduced during controlling the motor.

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 motor speed control circuit and a voltage-regulating module thereof are disclosed. The fan motor speed control circuit includes the voltage-regulating module and a driving module electrically connected to the voltage-regulating module. The driving module includes a pulse signal generating unit, a speed control unit, and a drive unit. The speed control unit compares a high frequency pulse signal generated by the pulse signal generating unit with a variable reference voltage signal output by the voltage-regulating module, and then outputs a control signal to the drive unit to proceed the speed control of the fan motor. In application, the voltage-regulating module and the driving module are electrically connected to a voltage source in parallel.