Abstract: An axial fan comprises a base, a rotor mounted on the base by a shaft, and a plurality of blades mounted on the rotor. The blade comprises a passive part corresponding to a feeder and an active part, so that a main airflow from the feeder drives the passive part rotating around the shaft to synchronously rotate the active part, to increase flow rate of airflow, to decrease the pressure and to dissipate heat generated from a heat source.

Abstract: The methods for starting a Hall-less single-phase BLDCM having an asymmetrical air gap are proposed. The provided methods are employed to input a specific amount of current impulse and stop the current impulse at a specific time such that the rotor of the single-phase BLDCM having an asymmetrical air gap can be realized to rotate in the pre-determined direction through one of the cogging torque and the rotor inertia after that specific time so as to accomplish the normal starting of a motor without the Hall-effect sensor.

Abstract: The method and circuit for controlling a sensorless single-phase BLDCM having a stator with a winding are proposed. The provided controlling circuit includes a power supply circuit, an inverter coupled to the winding and the power supply circuit, a BEMF detecting circuit coupled to the winding and the inverter and measuring a BEMF of the winding, and a controller coupled to the power supply circuit, the inverter and the BEMF detecting circuit and analyzing a status of the BEMF to control the BLDCM accordingly. The provided method is based on the motor winding time-sharing theory, and the controller controls the inverter to make the winding used as a driving element with loading current when the absolute value of the BEMF is relatively large and as a sensing element when the absolute value of the BEMF is relatively small.

Abstract: A coupling structure for a tandem motor includes two bearing sleeves formed with grooves thereon, a connector and elastic fasteners. The connector has a first end and an opposed second end, and each of the first end and second end is formed with at least one groove. A first elastic fastener is fit into the groove of the connector at the first end and received in the groove formed on one of the two bearing sleeve, and a second elastic fastener is fit into the groove of the connector at the second end and received in the grooves formed on the other bearing sleeve.

Abstract: A motor rotor. The motor rotor adapted to be used in a fan includes a hub, a metal plate and a magnet. The metal plate has a first end and a second end. The metal plate is disposed in the hub. The magnet is disposed in the metal plate. A method for manufacturing a motor rotor mentioned includes providing a metal plate having a first end and a second end; connecting the first and second ends to shape the metal plate as a ring; placing the metal plate in a hub; and placing a magnet in the metal plate.

Abstract: A rotor. The rotor includes a case, a reinforcing part, a shaft and a connecting element. The reinforcing part is formed with the case and defines an opening. The shaft extends into the opening. The connecting element connects the case and the shaft, with the reinforcing part disposed inside.

Abstract: A magnetic bearing assembly having a magnetic portion for simultaneously generating axially and radially magnetic forces and a bearing portion for supporting a shaft upon its rotation is disclosed. The magnetic bearing assembly according to the present invention can be utilized in a motor of a cooling fan to provide the substantially frictionless rotation and the precise position of the shaft. Thus, it requires no lubrication, results in less abrasion and produces low noise, all of which contribute to extend the operating life of the bearing.

Abstract: The proposed method for starting a motor having a stator, a rotor, a winding and an asymmetrical air gap, comprising the steps of: (a) exciting said winding with a current impulse such that said stator generates a magnetic field and going to one of steps (b) and (d); (b) driving said rotor to rotate in a first direction if a polarity of a portion of a specific tooth of said stator close to said air-gap and a polarity of a specific magnetic pole of said rotor corresponding to said tooth are opposite; (c) stopping said current impulse at a specific moment such that said rotor is rotated in a second direction by a cogging torque and going to step (f); (d) driving said rotor to rotate in a first direction if a polarity of a portion of a specific tooth of said stator close to said air-gap and a polarity of a specific magnetic pole of said rotor corresponding to said tooth are the same; (e) stopping said current impulse at said moment such that said rotor is rotated in a second direction by an inertia; and (f) dete

Abstract: A liquid-cooled heat dissipation module for circularly dissipating heat from a heat source. The liquid-cooled heat dissipation module includes a fan having a base; a pump disposed on the base; a heat sink coupled to the fan and having an opening to receive the pump; and a guide part disposed in the opening of the heat sink, communicated to the pump and having an outer surface, a through hole and a guide passage formed on the outer surface. The pump drives a working fluid in the liquid-cooled heat dissipation module to pass through the through hole, the pump and the guide passage to circularly dissipate heat.

Abstract: A liquid-cooled heat dissipation module for circularly dissipating heat from a heat source. The liquid-cooled heat dissipation module includes a base, a rotor supported by the base and having a hub, a first magnetic part, and a pump having a second magnetic part and a fixed seat. The fixed seat is coupled to the base and has a space to receive the second magnetic part. When the first magnetic part is rotating along with the rotor, the second magnetic part is driven by a magnetic interaction between the first and second magnetic parts so as to generate a circular flow of the working fluid in the pump.

Abstract: An axial flow fan. The axial flow fan includes an impeller, an annular structure, and a plurality of connecting elements. The impeller has a plurality of blades, arranged radially. Each blade has an outer periphery. The outer periphery has a top portion. The annular structure is attached to the top portion of the outer periphery of each blade. Each connecting element respectively connects each blade to the annular structure.

Abstract: A brushless DC motor drive apparatus for driving a rotor includes a drive circuit rotating the rotor, a current shutdown and auto-restart circuit coupled to the drive circuit, and a DC voltage comparison circuit coupled to the current shutdown and auto-restart circuit. The current shutdown and auto-restart circuit detects blockage of the rotor via the DC voltage comparison circuit and shuts off the power to the drive circuit accordingly.

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 stator structure of a motor. The stator structure has a base including a main body and a plurality of protrusions extending from the main body. A stator part has a plurality of magnetic-pole portions, wherein each protrusion is positioned in a gap between every two adjacent magnetic-pole portions when the stator part is disposed on the base, and a coil wound around the stator part. The outer circumference of the main body of the base includes a plurality of circular arcs with different radii, so as to provide a function of attaining bias when the motor is driven to start and preventing reduced rotational efficiency of the motor.

Abstract: A heat-dissipating device and a motor structure. The heat-dissipating device has a outer frame provided with a seat, at least two rotors, a control unit and a stator. The rotors are respectively disposed on the seat. The control unit is disposed on the seat for controlling the rotation of the rotors. The stator for driving the rotors includes a plurality of silicon steel sheets or iron core embedded in the seat and a plurality of coils. Controlling the rotors with a single stator and a single control unit reduce the volume and cost of the heat-dissipating device.

Abstract: A heat dissipation module includes a first heat dissipation apparatus, a second heat dissipation apparatus, at least one first flapper and at least one second flapper. The first heat dissipation apparatus has a first airflow passage, and the second heat dissipation apparatus has a second airflow passage. The first flappers and the second flappers are separately disposed within the first airflow passage and the second airflow passage. The first flappers and the second flappers are moved to an open position due to force generated by air flowing through the first airflow passage and the second airflow passage, and are moved to a closed position after the force is removed.

Abstract: A fan includes a fan base, a bearing assembly, a fan hub and a shaft. The fan hub is formed with an extrusion protruding from its top planar surface, and the shaft is fit into the bearing assembly and connected to the fan hub. The shaft has one end protruding from the top planar surface of the fan hub to form an extension portion, and the extension portion of the shaft is enclosed by and in close connection with the extrusion of the fan hub.

Abstract: A cooling fan with high heat-dissipating performance includes a plurality of blades; and a frame for receiving the blades therein, wherein the frame has a reduced height for exposing the blades to outside of the frame so as to allow air to enter into the frame via a top portion and a peripheral portion of the blades to improve air introduction and heat dissipating efficiency of the cooling fan. A cover may be mounted to a top surface of the frame, and formed with a plurality of openings for allowing air to enter into the frame through the openings; such an arrangement cam effectively enhance air intake and working efficiency of the cooling fan.

Abstract: Motors for fans are provided. The motor includes a stator and a rotor. The stator includes a plurality of magnetic poles. The rotor is coupled to the stator and includes a magnetic structure with a plurality of magnetic poles. Each magnetic pole has an interpolar portion. A uniform gap is formed between the stator and the magnetic structure.

Abstract: This specification discloses a serial fan comprising a plurality of rotor vanes, one or more supports and a frame. Each of the rotor vanes comprises an inlet, an outlet, and one or more blades. Each support supports at least one of the rotor vanes so that the corresponding rotor vane can rotate thereon. The frame connects all the supports. The rotor vanes are connected in series in the axial direction, and the design of each of the rotor vanes is such that the velocity vector of the air relative to one of the blades on the outlet side of the ith rotor vane plus the velocity vector of the blade of the (i+1)th rotor vane relative to that of the ith rotor vane gives the incoming velocity vector of the air relative to the (i+1)th rotor vane. This vector is essentially parallel to the extension direction of the blade on the inlet side of the (i+1)th rotor vane. Here, i is a natural number smaller than the number of the plurality of rotor vanes.