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 motor control device includes a sensing circuit, a phase-shifting circuit, a comparing circuit and a control circuit. The sensing circuit senses the motor to generate a sensing signal. The phase-shifting circuit is electrically connected to the sensing circuit and receives the sensing signal to generate a phase-shifting signal. The comparing circuit is electrically connected to the phase-shifting circuit and receives the phase-shifting signal to generate a comparing signal. The control circuit is electrically connected with the comparing circuit and the motor, and receives the comparing signal to generate a control signal so as to control the rotation speed of the motor.

Abstract: Motors comprising stators and rotors having a plurality of north poles and south poles and methods of controlling the same. A first sensor and a second sensor are provided. The first and second sensors are disposed on the stator in a manner that the first and second sensors never simultaneously detect boundaries between the north and south poles during rotation of the rotor. If any one of the first and second sensors continuously detects a north pole or a south pole for a predetermined duration, the motor is shut off.

Abstract: A motor controlling method and apparatus thereof are provided. The control method includes the steps of receiving a switching phase signal of coil while the motor is rotating, for generating a separate signal, comparing the phase signal and the separate signal to generate a first control signal, generating a current feedback signal equivalent to the first control signal, and comparing the current feedback signal and the separate signal for generating a second control signal so as to control the operation of the motor.

Abstract: A heat dissipation device and fan module. The fan module is fixed to a fan tray, which has a track with a first engaging portion. A securing member is disposed on a shield, comprising a second engaging portion. The second engaging portion enters the first engaging portion, fixing the fan module to the fan tray. An actuator connects the securing member and the shield. When external force deforms the actuator, the securing member deforms therewith, withdrawing the second engaging portion from the first engaging portion.

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 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 and a rotor structure thereof. The rotor structure has a case, an upper linking structure, a lower structure, and a rotating shaft. The case has an opening at the axle center. The upper linking structure has a fixing portion and a threaded portion. The minimum radius of the fixing portion is longer than the radius of the opening. The threaded portion is disposed in the opening. The lower linking structure has a thread corresponding to the threaded portion. The upper linking structure and the lower linking structure is screwed together to secure the case therebetween. The rotating shaft is fixed in the upper linking structure or the lower linking structure.

Abstract: A fan is disclosed for use in a system, and the system has at least one connection structure. The fan is mainly composed of an impeller and a base, and the impeller is connected to the base. The impeller at least has a hub, a plurality of blades and a driver. The base has at least one engaging member, and the engaging member is corresponding to the connection structure. Further, the fan is fixed on the system by connecting the engaging member and the connection structure together.

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 thermal control variable-speed circuit without switching noise is connected with a driving circuit, which controls the rotation speed of a fan motor using a driving voltage. The thermal control variable-speed circuit includes a reference voltage output circuit and a driving voltage control circuit. The reference voltage output circuit outputs a corresponding reference voltage signal according to ambient temperature changes. The reference voltage output circuit has one end connected to a first resistor in series and to a second resistor in parallel. The driving voltage control circuit outputs a corresponding driving voltage according to the magnitude of the reference voltage signal.

Abstract: A protecting device of a fan system includes at least one first switch element and at least one control unit. The first switch element receives a first input signal. The control unit is electrically connected with the first switch element, receives the first input signal, and controls the first switch element to turn on or turn off according to the first input signal. The control unit stops outputting the first input signal when the first switch element turns on. The control unit outputs the first input signal when the first switch element turns off, so that a fan of the fan system can be driven by the first input signal.

Abstract: A control device of a fan system includes a temperature sensing module, a comparing module and a driving module. The temperature sensing module senses an external temperature and generates a sensing signal according to the external temperature. The comparing module receives the sensing signal and outputs a comparing signal according to the sensing signal and a reference voltage signal. The driving module, which is electrically connected with the temperature sensing module and the comparing module, supplies a working voltage to the temperature sensing module and the comparing module, and outputs a rotating speed control signal according to the sensing signal or the comparing signal.

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 full-bridge circuit for a heat dissipation system. The heat dissipation system further includes a fan and a control circuit. The control circuit outputs a first control signal and a second control signal. The full-bridge circuit includes a first control line having a first switch and a third switch serially coupled, a second control line includes a second switch and a fourth switch serially coupled, and a induction coil having one terminal coupled between the first and third switches and the other terminal coupled between the second and fourth switches. The ON/OFF states of the first and second switches are controlled by the first and second control signals respectively. The ON/OFF states of the third and fourth switches are controlled by two driving voltage sources respectively.

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.

Abstract: A fan motor control device comprises a clock signal generator and a drive unit. The clock signal generator generates a low-frequency clock signal. A frequency of low-frequency clock signal is less than 23 KHz. The drive unit converts the low-frequency clock signal to a high-frequency drive signal and outputs the high-frequency drive signal to drive the fan motor. A frequency of the high-frequency drive signal is higher than 23 KHz.

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.