Abstract: A fan for generating an air flow by rotating an impeller with a motor is provided. A cylindrical outer side surface of a rotor of the motor is press-fitted to an inner side surface of the impeller cup which is substantially cylindrical. An outer side surface of the impeller cup is a portion of a circular conical surface, thereby increasing the amount of air generated and transmitted by the fan. A gap is formed between the outer side surface and the inner cylindrical surface of the impeller cup. The cylindrical outer side surface of the rotor is connected to the inside of the inner cylindrical surface of the impeller cup coaxially with each other. Thus, the impeller and the rotor can be reliably fixed to each other with improved performance of transmitting air.

Abstract: A cooling apparatus is for dissipating heat from an electronic device. The cooling apparatus includes a casing, an impeller, and a motor. The casing is for absorbing the heat and allowing coolant to flow therein. The impeller is received in the casing. The motor is received in the casing, and is for providing a force to drive the impeller to rotate to force the coolant to flow. The coolant flows between the casing and the motor to take the heat away.

Abstract: An arrangement of a low air inlet and a circuit for driving a torque generator in an ultra-compact centrifugal fan is disclosed. In the ultra-compact centrifugal fan, a region occupied by the circuit is not completely arranged radially inside a cup-shaped portion to which an impeller is attached. At least a part of the low air inlet provided on a bottom of a housing of the centrifugal fan is arranged in a range of predetermined angle in an imaginary ring-shaped portion surrounding a base portion covered by the cup-shaped portion. A part of the circuit, that is not covered by the cup-shaped portion, is arranged upstream of the range of the predetermined angle in a flowing direction of airflow.

Abstract: A motor includes a balancing member having a surface. The surface has a shaft coupling portion and a magnetically conductive portion. A stator is coupled to the balancing member. A rotor includes a hub, a shaft, and a permanent magnet. The shaft and the permanent magnet are mounted inside the hub. The shaft is rotatably coupled to the shaft coupling portion. The permanent magnet includes a magnetically attracting face aligned with the magnetically conductive portion of the balancing member. The magnetically attracting face and the magnetically conductive portion attract each other to maintain stable rotation of the rotor while providing a simplified structure. The balancing member can be interconnected to a housing, and the hub can include a plurality of blades to form a heat dissipating fan. When the rotor rotates, air currents are drawn by the blades to a heat source for heat dissipating purposes.

Abstract: A fan includes a frame, a stator and a rotor. The stator is disposed in the frame, and the rotor is disposed in the frame and coupled with the stator. The rotor includes a connecting element, an impeller and a shaft. The connecting element has a flange. The impeller is disposed on a periphery of the connecting element. The flange is embedded with the impeller. One end of the shaft is connected to the connecting element and the impeller is rotated when the shaft rotates.

Abstract: An electronic device includes a casing and a centrifugal blower. The casing includes a bottom cover and a top cover. A sidewall extends from the bottom cover towards the top cover. The centrifugal blower is surrounded by the sidewall and includes a supporting member mounted to the bottom cover, and an impeller rotatablely supported by the supporting member. The impeller includes a hub and a plurality of blades extending outwardly from the hub. Outer portions of the blades extend beyond the supporting member along a radial direction of the hub. Inner portions of the blades have a height gradually increasing along an outward direction. The outer portions have a height equal to a maximum height of the inner portions. Bottom faces of the outer portions of the blades are located below a top surface of a base plate of the supporting member.

Abstract: A stator device includes a base having a shaft tube receiving a bearing. The shaft tube includes a top end having at least one groove. A stator unit is mounted around an outer periphery of the shaft tube. The stator unit includes at least one limiting member extending through the at least one groove into the shaft tube. The at least one limiting member prevents the bearing from disengaging from the shaft tube, enhancing assembling convenience. The stator can be coupled with a rotor to form a motor with enhanced assembling convenience and enhanced rotational stability. The base can be interconnected by connecting members to a housing having air inlet and outlet sides. Vanes can be formed on the hub of the rotor to form an impeller. Thus, a heat-dissipating fan can be formed from the stator device.

Abstract: The described embodiments relate to fan units. One exemplary fan unit includes a housing supporting a motor. The fan unit also includes an impeller coupled to the motor and configured to be rotated by the motor. The impeller comprises at least a first structure configured to move air past the housing and at least one second different structure configured to force air into the housing.

Abstract: A support system for a cooling fan for a heat exchanger. A suspension system supports an inner hub inside an outer support structure. The inner hub or ring supports the fan and motor. The suspension system includes an array of spiral support arms, extending from the inner hub to the outer supports. These arms have both spanwise and chordwise camber. The particular suspension system increases natural frequencies of the support system, over that wherein purely radial arms connect the inner hub and outer supports.

Abstract: A dust-proof and anti-oil leakage structure for a fan comprises a blade assembly, an outer frame and a center stator. On a spindle between the blade assembly and the outer frame are installed in sequence an outer frame, an upper insulating cover, a silicon steel lamination, a lower insulating cover, a printed circuit board heat sink, an elastic gasket with a cross hole, a washer, a copper sleeve, a round elastic gasket.

Abstract: Fan includes wires electrically connected to the circuit board outwardly extends from a base toward a housing along a rib connecting the base supporting a motor and the housing. The housing includes a wire-receiving section defined by a through hole extending in the housing, and a slit connecting the through hole and an outside of the housing along a direction in which the through hole extends. The wires are inserted into the wire-receiving section via the slit, and then, led outside of the housing through the wire-receiving section. A wire-holding member is then inserted into the wire-receiving section to close the slit to prevent the wires from coming out of the wire-receiving section and to restrict the movement of the wires.

Abstract: An apparatus comprises a rotor supported for rotation about a longitudinal axis. The rotor comprises an elongate tubular member enclosing a substantially cylindrical space, the elongate tubular member having a first open end defining an inlet, and a second open end defining an outlet. The apparatus includes at least one electrically conductive element for generating a magnetic field when electric current flows therethrough and for controlling rotation of the rotor. At least a part of at least one said electrically conductive element is aligned axially with at least a part of said elongate tubular member. The elongate tubular member comprises conveying means adapted so that upon rotation of said rotor, at least one body is caused to move in a direction from said inlet toward said outlet, through the substantially cylindrical space.

Abstract: A fan device with improved speed control module includes a stator, a rotor, and a speed control module. The stator has a driving unit outputting currents for the stator to generate alternative magnetic fields and thus turn the rotor. The speed control module includes a control unit and a speed adjusting circuit, with the control unit generating a control command for the driving unit and further outputting a state signal for the speed adjusting circuit to control whether a PWM signal enters the control circuit or not.

Abstract: An impeller and at least a portion of a cooperating peripheral volute may be integrated into, and preferably are integrally injection molded with, concentric outer rotor and inner stator assemblies, respectively, to achieve a low profile precision impeller mechanism based on an improved brushless d.c. motor with low length (L) to diameter (D) ratio and suitable for use in a variety of other applications. In one practical embodiment of such a motor, a rotating cap has an inner circumference which is molded about an outer ferromagnetic back ring that in turn supports a permanently magnetized ring shaped rotor magnet having a number of poles of alternating polarity defined about its inner circumference and separated by a relatively small cylindrical air gap from the outwardly projecting radially oriented selectively magnetized poles of a fixed stator assembly. In one exemplary embodiment, the rotor may have 8 poles and the stator may have 9 poles.

Abstract: A heat dissipation device (1) includes an electric fan (20) and a heat sink (10). The fan includes a fan impeller (40) which includes a hub (41) and a plurality of blades (42) extending radially and outwardly from the hub (41). The hub (41) includes an upper portion (417) and a bottom portion (413). An air inlet (411) is formed near the upper portion (417) and an air outlet (412) is formed near the bottom portion (413). The blades (42) have portions on the bottom portion of the hub which are extended toward a center of the air outlet for driving more air to the center of the air outlet (412), whereby more air can flow to a center of the heat sink.

Abstract: A fan motor device includes a fan base, an impeller set and a motor set. The fan base extends a central barrel with ball bearings fitting with the barrel. The impeller set further includes an impeller, a shaft, a spring, a motor case and a magnet. The motor set further includes an insulation frame, a silicone sheet set, a coil and a circuit board. The barrel has an annular deep groove between the inner circumferential side and the outer circumferential side thereof for a stop ring being attached to an inner wall surface of the groove to reinforce the outer circumferential side so as to prevent the barrel from bending deformation and the motor set from displacing eccentrically or loosening off.

Abstract: A fluid pump having a case with a pump chamber defined by axial side surfaces and a circumferential surface, a suction port and a discharge port both provided in the circumferential surface so as to communicate with the pump chamber, an impeller formed into a disc shape and rotatably mounted in the pump chamber, a pressure generating protrusion, which generates pressure by rotation of the impeller and is located inside the pump chamber at a radial position, and a motor, which drives the impeller, installed in the case and having a stator and a rotor to which the impeller is attached for rotating together.

Abstract: Some embodiments of the present invention provide a system that controls a temperature variation in a computer system. First, a performance parameter of the computer system is monitored. Next, a future temperature of the computer system is predicted based on the performance parameter. Then, a pitch of one or more blades in a cooling device in the computer system is adjusted based on the future temperature to control the temperature variation in the computer system.

Abstract: A cooling fan includes a fan housing, a stator mounted in the fan housing and a rotor rotatablely supported by the stator. The stator includes a stator core, an insulating frame attached to the stator core and stator coils wound on the insulating frame and around the stator core. The insulating frame electrically insulates the stator coils from the stator core. The stator core includes a main body and a plurality of claws. Every two neighboring claws define a receiving room therein. The insulating frame includes a bottom portion located at a bottom of the stator core and a plurality of flanges extending upwardly from the bottom portion into the receiving rooms of the stator core, respectively. A height of the flanges is no less than that of the stator core.

Abstract: A small sized heat dissipating fan comprises a housing, a stator and a rotor. The housing includes a carrying base to hold the stator and rotor. The stator includes a magnetizing member having a plurality of coils, and a circuit board electrically connecting to the coils and having a driving circuit and a speed adjuster. The driving circuit, the speed adjuster and the coils electrically connect to each other. The rotor includes a shaft, an impeller fixed to one end of the shaft, and an annular magnet. The other end of the shaft extends through the magnetizing member. The shaft is rotatably coupled to the stator. The annular magnet is mounted to an inner periphery of the impeller and faces the magnetizing member of the stator. Consequently, by adjustment of resistance of the speed adjuster, the rated rotational speed of the heat dissipating fan can be changed.

Abstract: A cooling fan includes a base, a stator mounted on the base and a rotor rotatablely supported by the stator. A central tube is formed at a central portion of the base for mounting the stator thereon. The rotor includes a hub, a hollow shell, a permanent magnet and a plurality of blades. The hub includes a top wall and a sidewall extending downwardly from an outer periphery of the top wall. The shell is attached to an inner surface of the sidewall of the hub. An annular bottom flange is formed at a bottom end of the shell. The permanent magnet is attached to an inner surface of the shell. The permanent magnet extends to abut directly against a bottom surface of the top wall of the hub.

Abstract: A sleeve support portion is arranged to support a sleeve having a rotating shaft inserted therein such that the rotating shaft is rotatable. A plurality of ribs extending in an axial direction is provided on an inner surface of the sleeve support portion. The ribs are preferably spaced from each other in a circumferential direction centered on the rotating shaft, and arranged to make contact with at least a portion of the sleeve. The ribs include a plurality of types of ribs, each type of the ribs having a different axial position of an axial edge, on an axially opening portion side, of a contact surface thereof which is arranged to make contact with the sleeve.

Abstract: An outer rotor type fan-motor includes: a rotational shaft; a bearing assembly that rotatably supports the rotational shaft; a stator installed at an outer side of the bearing assembly; a permanent magnet assembly that covers an outer side of the stator at a certain distance and is installed at the rotational shaft; and a fan that includes a shaft fixing part for fixing the rotational shaft, a hub for covering an outer side of the permanent magnet assembly at a certain distance and blades formed around the hub. An insulation space is formed between the permanent magnet assembly and the fan to prevent transfer of vibration and noise of the permanent magnet assembly to the fan, and vibration or noise of high frequency can be reduced.

Abstract: A rotor yoke includes a substantially flat or annular flat cover portion coaxial or substantially coaxial with a rotational axis and a substantially cylindrical side wall portion extending from an outer circumference of the cover portion in a parallel or substantially parallel relationship with the rotational axis. The rotor yoke further includes a substantially annular flange portion extending radially outwards from an open end of the side wall portion. The cover portion and the side wall portion define a cup portion whose center of gravity deviates from the rotational axis in a plane perpendicular or substantially perpendicular to the rotational axis, and the flange portion has an outer circumferential circle whose center deviates from the rotational axis in a direction opposite to the deviation direction of the center of gravity of the cup portion.

Abstract: A motor rotor includes a hub, a metal ring and a magnet ring. The hub includes a peripheral wall. The metal ring includes an engaging portion and is formed by bending a strip of metal plate to form a cylindrical ring mounted to an inner surface of the peripheral wall of the hub. The metal plate includes a first positioning portion and a second positioning portion respectively on two ends thereof. The first and second positioning portions are joined together to form the engaging portion. The magnet ring is mounted to an inner radial surface of the metal ring. Accordingly, by configuration of the engaging portion, stable formation of the cylindrical metal ring is assuredly provided.

Abstract: An electric motor includes a stator portion, a rotor portion, and a bearing mechanism, wherein the rotor portion includes a rotor holder having a substantially cylindrical shape with a closed end, and a field magnet fixed to an inner circumference of the rotor holder; the stator portion includes a stator, a base portion to which the stator is fixed, and a magnetic member; and the magnetic member includes a cylindrical portion having a substantially cylindrical shape into which a lower end portion of an insulator of the stator is inserted, the lower end portion being a portion of an outer portion of the insulator and opposing the base portion, and a flat portion having a substantially annular shape which spreads outwardly in a radial direction from a lower edge of the cylindrical portion and opposes a lower edge of the field magnet.

Abstract: A fuel pump has a housing defining a cavity. A rotor of an electric motor is carried in the cavity for rotation about a drive axis. An annular pump impeller is supported in the cavity separate from the rotor and is driven by the rotor for rotation about the drive axis.

Abstract: The described embodiments relate to fans units. One exemplary fan unit includes a housing supporting a motor. The fan unit also includes an impeller coupled to the motor and configured to be rotated by the motor. The impeller comprises at least a first structure configured to move air past the housing and at least one second different structure configured to force air into the housing.

Abstract: A fan motor may include a rotor part having a drive magnet and a stator part having a drive coil and rotatably holding the rotor part. The rotor part may include a rotor yoke to which the drive magnet is fixed on an inner peripheral side of the rotor yoke, an impeller which is provided with a plurality of blades and disposed on an outer peripheral side of the rotor yoke, and a plurality of ribs which are protruded from at least one of an inner peripheral face of the impeller and an outer peripheral face of the rotor yoke in a radial direction. The rotor yoke may be press-fitted to the impeller so that end parts in the radial direction of the ribs are abutted with at least one of the inner peripheral face of the impeller and the outer peripheral face of the rotor yoke, and gap spaces are formed between adjacent ribs of the plurality of the ribs and between the inner peripheral face of the impeller and the outer peripheral face of the rotor yoke.

Abstract: A cooling fan (1) includes a fan housing (10), a stator (20), a rotor (30) and a bearing assembly (40). A tube (111) extends upwardly from a central portion of the fan housing. The stator is mounted around the tube. The bearing assembly includes a ball bearing (333) and a sleeve bearing (335) received in two ends of the tube, respectively. The rotor has a shaft (336) extending into and roratably supported by the bearing assembly. An elastic element (332) is arranged on the ball bearing to provide a pressing force on the ball bearing toward the sleeve bearing. An oil retaining element (339) is arranged around a bottom end of the shaft and spaced from the shaft. The oil retaining element is attached to the sleeve bearing to provide oil for the sleeve bearing.

Abstract: A stator structure of a motor includes a first magnetic substrate, a second magnetic substrate and a plurality of coil units. An outer profile of the first magnetic substrate has a plurality of first protruding parts, and an outer profile of the second magnetic substrate has a plurality of second protruding parts. The first magnetic substrate and the second magnetic substrate are correspondingly disposed. The coil units disposed between the first magnetic substrate and the second magnetic substrate respectively have a coil wound around a central axis of the coil unit, and at least one magnetically conductive element disposed within the coil.

Abstract: A fan assembly including a rotation shaft, a permanent magnet having a receiving space therein and rotatable around a central axis of the rotation shaft, a fan including a hub having a receiving space therein with one side open and disposed outside the permanent magnet, the fan being rotatable around the central axis of the rotation shaft, a stator disposed inside the permanent magnet, and a blocking portion disposed at the open side of the hub in an axial direction, the combination configured to block an introduction of foreign materials into the fan assembly and to reduce the size of the fan assembly.

Abstract: A fan includes a fan frame having an upright barrel, a fan blade unit having a fan hub with radial blades, and a driving module formed of a stator, an axle bearing, a core shaft and a rotor for causing rotation of the fan hub with the blades relative to the stator. The stator has a collar affixed to the barrel of the fan frame, radial ribs extending from and spaced around the periphery of the collar, and three-dimensional wings respectively connected to the free ends of the radial ribs each three-dimensional wings having a smoothly arched and radially and axially extending outer surface.

Abstract: An ultra-thin miniature pump applied to transport a fluid includes a main body, a rotor, and a stator. The main body includes a cover part and a bottom part. A joint surface between the cover part and the bottom part possesses an anti-leakage device, and a chamber including a suction port and a discharge port is formed inside the main body. The rotor disposed in the chamber includes a magnet set, an impeller, and a central shaft. The magnet set is connected on the surface of the impeller, and the impeller with the magnet set is aligned by the central shaft and rotates in coaxial. The stator disposed in the chamber includes a plurality of coils corresponding to the magnet set axially. The coils and the magnet set generate an axial magnetic flux to make the impeller rotate for transporting the fluid from the suction port to the discharge port.

Abstract: A cooling fan with an outer rotor motor supported by a fan housing. A motor housing is disposed within a conduit through the fan housing, while the outer rotor motor is disposed within the motor housing. A plurality of support members coupled between the motor housing and the fan housing enable the fan housing to support the motor housing. A hub is rotatably coupled to the outer rotor motor and has a first portion disposed within the motor housing and a second portion disposed outside of the motor housing. A plurality of blades extends radially from the second portion said hub.

Abstract: A miniature fan, particularly an axial fan, has a space-conserving structure which permits sophisticated electronic control circuits within a limited amount of space. It features an electronically commutated motor (ECM) including an internal stator 68, an external rotor 27 on a shaft 62, and a fan wheel 28 mounted on the rotor and bearing fan blades 26. The motor flange 40? supports a bearing tube 60 which rotatably journals the rotor shaft 62 and is formed with a cavity 84 which receives a first circuit board 86 devoted to control of motor speed and/or voltage, and a second circuit board 96 which supports a galvanometric sensor 100 which senses the rotational position of the rotor, for purposes of triggering commutation of the motor stator windings 68 at appropriate times.

Abstract: A rotor of a motor includes a shaft, a magnetically conductive shell and a connecting element. The shaft has a groove formed at one end of the shaft. The central portion of a top wall of the magnetically conductive shell has at least one extending portion disposed adjacent to the groove, and at least one part of the extending portion is radially projected onto the groove. The connecting element connects the end of the shaft and the extending portion of the magnetically conductive shell. A fan including above-mentioned rotor is also disclosed.

Abstract: The described embodiments relate to fans units. One exemplary fan unit includes a housing supporting a motor. The fan unit also includes an impeller coupled to the motor and configured to be rotated by the motor.

Abstract: A bearing bracket including a metal base and a bushing is provided. The metal base has an opening at its central portion. The bushing of the bearing bracket is made of plastic. The bushing encloses an axial portion or/and a radial portion of the metal base by injection molding. Furthermore, the bearing bracket further includes an anti-vibration member disposed on at least one side surface of the metal base.

Abstract: A cooling fan includes a fan housing (10) having a central tube (18) extending upwardly therein. A sleeve bearing (40) is received in the central tube. A stator (20) is mounted around the central tube. A rotor (30) has a shaft (36) being rotatably received in the sleeve bearing. The sleeve bearing defines a bearing hole (42) therethrough. The bearing hole (42) receives the shaft of the rotor to rotate therein. A plurality of irregular pores and at least one blind hole (44) are defined in the sleeve bearing and impregnated with lubricant oil.

Abstract: A fan includes an impeller and a motor. The motor includes a rotor structure and a bearing structure. The motor is used to drive the impeller and the rotor structure has a shaft. The shaft is connected to the impeller. The bearing structure includes an oil-retaining bearing, a base and a sleeve. The oil-retaining bearing is used to dispose the shaft and the base is used to support the oil-retaining bearing. The sleeve includes at least one resisting part and a circular sidewall. The circular sidewall is covered the outside of the oil-retaining bearing. The resisting part is disposed on the top surface of the circular sidewall and extended to the center of the oil-retaining bearing.

Abstract: A cooling fan includes a fan housing (30) having a central tube (34) extending upwardly therefrom, a bearing (61) received in the central tube and defining a bearing hole (62) therein, a stator (20) mounted around the central tube, and a rotor (10) including a hub (12) having a shaft (18) extending from the hub into the bearing hole of the bearing. The stator includes a stator core, and upper and lower insulating frames (28a, 28b) respectively located at upper and lower sides of the stator core. An oil retaining structure (288) is integrally formed with the upper insulating frame, and extends inwardly from a top of the upper insulating frame to an outer surface of the shaft.

Abstract: A heat dissipation fan includes a fan frame, a stator mounted to the frame, and a rotor rotatably disposed around the stator. The fan frame includes a bracket, a central tube for positioning the stator, and a supporting member. The supporting member is made of a material having a higher bending strength than a plastic material used to form the bracket and the central tube. The supporting member includes a main body connected to the central tube, a plurality of ribs extending radially outwardly from the main body, and a plurality of engaging units formed at free ends of the ribs, respectively. The engaging units are embedded in the bracket for integrally connecting the central tube to the bracket.

Abstract: Compressor comprising a housing (1a, 1b) and with at least one partly electric-motor-driven impeller (3) arranged on a central shaft (5). The invention is characterized in that the impeller (3) is provided with a tubular part (6) surrounding the central shaft (5), and also in that a tubular carrier (2) extending in between the central shaft (5) and the tubular part (6) is arranged firmly on the housing, in which carrier (2) the central shaft (5) is rotatably mounted.

Abstract: A motor includes a support member (40) having a bearing housing (20) defining a bearing hole (21) therein, a stator assembly (50) mounted to an outer periphery of the support member, and a rotor assembly (60) having a rotary shaft (68) extending into the bearing hole and a permanent magnet (66) confronting the stator assembly. A bearing pattern (100) is formed on either of the bearing housing and the rotary shaft. The bearing pattern includes a number of first and second grooves (13, 16) arranged circumferentially in an alternate fashion. Each of the first grooves is in communication with one adjacent second groove at an edge of the bearing pattern. Lubricating oil filled in the bearing pattern to establish dynamic pressure to separate the shaft and the bearing sleeve in radial direction when the shaft rotates.

Abstract: The present invention provides an improved structure of the magnetic shaft of a cooling fan. A magnetic attraction component is comprised of a magnetic ring, a magnetic inductive bottom board, and a magnetic inductive ring. The magnetic field generated by the magnetic ring is guided from the upper and lower side by the magnetic inductive ring and the magnetic inductive bottom board respectively, so that the range of magnetic field scattered by the magnetic ring is effectively and reliably guided and suppressed. The range of the magnetic field is reduced to the smallest possible, and interference with other components is minimized within the cooling fan, working stability and quality of the cooling fan being enhanced.

Abstract: A motor according to the present invention includes a boss portion 34 preferably includes an inner ring portion 342 having at an axially lower end surface thereof a substantially ring shaped convex portion 3421. The boss portion 34 preferably includes at a central portion thereof a through hole at which a shaft 32 is press fitted. A rotor holder 31 having a substantially cylindrical shape includes a through hole 321 centered about a rotary axis. The through hole 321 and the inner ring portion 342 of the boss portion 34 are fitted to one another. The convex portion 3421 includes a portion plastically deformed outwardly in the radial direction so as to sandwich an inner circumferential surface 3211 of the rotor holder 31. The inner circumferential surface of the impeller cup portion 22 includes a plurality of convex portions 221 near an upper portion thereof. The rotor holder 31 is press into the inner circumferential surface of the impeller cup portion via the convex portions 221.

Abstract: A cooling fan includes a fan housing (10) having a central tube (15) extending upwardly therefrom, a bearing (20) defining a bearing hole (22) therein, a stator (30) mounted on the central tube, and a rotor (40) including a hub (12) having a shaft (18) extending from the hub into the bearing hole of the bearing. The bearing is received and fixedly connected to the central tube during the plastic injection molding of the fan housing; thus the bearing and the central tube are integrally connected together. The bearing can be precisely and firmly secured to the central tube of the fan housing.

Abstract: A motor includes a stator, a rotor, a top magnetic structure, and a bottom magnetic structure. The stator is disposed in a frame. The rotor is also disposed in the frame, corresponding to the stator. The rotor includes a shaft extending axially from the rotor. The bottom magnetic structure is at the bottom of the frame. The top magnetic structure is on the top of the frame. The top and bottom magnetic structures are opposite to each other in an axial direction. Magnetic attraction generated between the first magnetic structure and the shaft, and the second magnetic structure and the shaft positions the shaft therebetween such that the first magnetic structure, the second magnetic structure, and the shaft are coaxially aligned.

Abstract: An axial flow fan includes a housing defining an air inlet and an air outlet, a motor mounted to the housing and an impeller including blades. The housing includes an expanded portion adjacent the air outlet. In the expanded portion, the inner diameter of the housing increases towards the air outlet so that the expanded portion has an inner end where its diameter is smallest. The trailing edge of each blade is inclined, with respect to a plane perpendicular to the axis of rotation of the impeller, so as to extend toward the air inlet from a radially innermost end of the edge to a radially outermost end of the edge. The radially outermost end of the trailing edge is disposed closer to the air inlet than the inner end of the expanded portion, and the radially innermost end of the of the trailing edge is disposed closer to the air outlet than inner end of the expanded portion.