Abstract: A contra-rotating fan structure includes a first base, a first fan, a second base, and a second fan. The first fan is rotatably disposed on the first base and includes a first hub. The first hub has a first largest width. The second fan is rotatably disposed on the second base and includes a second hub. The second hub has a second largest width. The first base and the second base are located between the first fan and the second fan. The second largest width is greater than the first largest width.

Abstract: A series-connected fan includes a first fan and a second fan. The first fan includes a first frame, a first base, first static blades and a first impeller. The second fan includes a second frame, a second base, second static blades and a second impeller. A first underframe of the first frame is connected to a second underframe of the second frame. The first static blades are disposed around the first base and connected to the first base and the first underframe. The second static blades are disposed around the second base and connected to the second base and the second underframe. The first impeller includes a first hub and first rotor blades. The second impeller includes a second hub and second rotor blades. The cross-sectional area of the first hub increases along a direction from the top of the first hub to the bottom of the first hub.

Abstract: A fan impeller includes a hub, a shaft, a metal housing, a magnetic ring and a plurality of blades. The outer periphery of the hub has a curved surface. The shaft is disposed in the hub and connected to the hub. The metal housing has an annular shape and is disposed in the hub. The magnetic ring is disposed at the inner side of the metal housing. The blades are disposed around the outer periphery of the hub.

Abstract: A fan includes a frame, an impeller and a motor. The frame includes a base, a frame housing and a plurality of static blades. The frame housing includes an outlet. The static blades are disposed around the outer periphery of the base and connect between the base and the frame housing. A distance is provided between the outlet and the ends of the static blades located adjacent to the outlet, and the static blades are not protruding from the outlet. The impeller includes a hub and a plurality of rotor blades. The hub has a curved surface. The slopes of the straight lines connecting any two points on the curved surface are not equal. The rotor blades are disposed around the outer periphery of the hub. The motor is disposed on the base, and connects with and drives the impeller to rotate.

Abstract: An impeller includes a hub and blades. In radial direction, an upper surface of the blade near the outer edge includes a groove structure, a lower surface of the blade relating to the groove structure includes a peak structure, the lower surface of the blade includes a recess structure aside the trailing edge or the leading edge. The recess structure is connected to the peak structure. The blade has at least five airfoils from the inner edge to the outer edge. The blade is defined by continuously connecting the at least five airfoils at different sections in sequence so as to form the groove structure and the peak structure respectively on the upper surface and the lower surface. The groove structure and the peak structure are aside the outer edge of the blade.

Abstract: A mixed-flow fan includes a base including a bottom channel, an outer cover disposed on the base, a motor disposed on the base, a hub located between the outer case and the motor, and a blade connected to the hub. A main channel is formed between the outer cover and the hub, and is connected to the bottom channel. The main channel extends in the first direction, and the bottom channel extends in the second direction.

Abstract: An impeller comprises a hub and a plurality of blades surrounding the hub. The hub comprises a shaft. Each blade includes a leading edge, an outer edge, a middle portion and a trailing edge. The leading edge, the outer edge and the trailing edge are around three sides of the middle portion. From the hub outwardly shaft, the height of the leading edge to the horizontal plane of the lowest of the blade gradually decreases first and then gradually increases.

Abstract: A fan includes a frame, an impeller, and a motor. The impeller includes a hub, blades, and air-guiding plates. The hub has a tapered shape and the width of the hub gradually increases. The hub has an air vent. The blades are disposed around the outer periphery of the hub. The air-guiding plates are disposed around the inner periphery of the hub. The motor is disposed in the frame, and connects to and drives the impeller to rotate. The motor includes a stator structure and a rotor structure. The rotor structure includes a shaft, a magnetic conductive housing, and a magnetic element. One end of the shaft connects to the magnetic conductive housing. The magnetic element is disposed around the inner periphery of the magnetic conductive housing and located corresponding to the stator structure. The top surface of the magnetic conductive housing has at least one opening.

Abstract: A fan includes a fan frame, an impeller, and at least a supporting member. The fan frame includes a bottom plate and a cover plate spaced from the bottom plate. The bottom plate and the cover plate together define a first accommodating space. The cover plate has an air inlet disposed in an axial direction. A side of the fan frame is provided with at least an air outlet. The impeller is disposed in the first accommodating space and includes a hub and a plurality of blades. A cross-sectional area of the hub increases gradually along a direction from the cover plate to the bottom plate. The blades are disposed around the periphery of the hub. The supporting member is disposed between the bottom plate and the cover plate for supporting the cover plate.

Abstract: A mixed flow fan includes a bottom base, an outer cover disposed on the bottom base, a motor disposed on the base, and a hub located between the outer case and the motor. The hub includes a first outer surface and a second outer surface connected to the first outer surface and inclined relative to the first outer surface. The slope of the first outer surface relative to the central axis is greater than the slope of the second outer surface relative to the central axis. The base includes a side surface adjacent to the second outer surface. The slope of the side surface relative to the central axis is equal to the slope of the second outer surface relative to the central axis.

Abstract: A fan includes a fan frame and a driving device. The fan frame includes a base, a frame shell and static blades arranged on the periphery of the base. The driving device includes a stator structure and a rotor structure. The stator structure includes a stator magnetic pole group and a bushing. The rotor structure includes a bearing, a shaft, a rotor shell, a magnetic structure and blades. The shaft is connected with the rotor shell and disposed through the bearing. The stator magnetic pole group magnetically drives the magnetic structure to rotate the rotor shell. The blades are arranged on the periphery of the rotor shell. Two ends of the frame shell are configured with two turning portions, respectively. The two turning portions are disposed between parts of the frame shell with different curvatures.

Abstract: A fan is provided. The fan includes a frame, a rotor and a stator. The rotor is received in the frame and includes a magnetic part, a metal housing, a hub and a plurality of blades. The metal housing is telescoped on the magnetic part. The hub is telescoped on the metal housing. The blades are formed on the hub. The stator is received in the frame. The stator includes a plurality of silicon-steel sheets which form a silicon-steel sheet outside diameter, the silicon-steel sheet outside diameter is greater than 42 mm and wherein the rated speed of the fan is greater than 8000 RPM.

Abstract: A mixed-flow fan includes a base including a bottom channel, an outer cover disposed on the base, a motor disposed on the base, a hub located between the outer case and the motor, and a blade connected to the hub. A main channel is formed between the outer cover and the hub, and is connected to the bottom channel. The main channel extends in the first direction, and the bottom channel extends in the second direction.

Abstract: A fan includes a motor, an impeller and a heat-dissipating structure. The motor includes a stator magnet assembly, a frame, a first circuit board, and a cover. The frame supports the stator magnet assembly. The frame and the stator magnet assembly define a first accommodating space, and the first circuit board is disposed in the first accommodating space. The cover covers the first circuit board. The motor drives the impeller and the impeller includes a hub and a plurality of first blades. The hub has at least a heat-dissipating hole. The first blades are disposed around the hub, and the heat-dissipating structure is disposed at the outer side of the hub. The heat-dissipating structure has a baffle and at least a second blade extended from the baffle and located corresponding to the heat-dissipating hole.

Abstract: A fan includes an impeller and a frame. The frame is used for accommodating the impeller. The frame includes a plurality of static blade groups. Each of the static blade groups has a plurality of static blades. Moreover, at least one first static blade of a first static blade group and at least one first static blade of a second static blade group are symmetric with respect to a central axis of the frame.

Abstract: A fan assembly and a fan frame thereof are disclosed. The fan assembly includes a fan frame and an impeller disposed in the fan frame. The fan frame has an air inlet end and an air outlet end, and includes a sidewall, a top portion and a bottom portion. The top portion is disposed close to the air inlet end and connected to one end of the sidewall. The bottom portion is disposed close to the air outlet end and connected to the other end of the sidewall. The bottom portion has at least one silencing structure.

Abstract: A fan includes a frame and an impeller including a hub, a plurality of first blades, a first ring-shaped structure, and a plurality of second blades. The first blades are disposed around the hub. The hub and the first blades are surrounded by the first ring-shaped structure connected with the ends of the first blades, and a central area is structured therebetween. The second blades are connected with an outer rim of the first ring-shaped structure. The frame includes a base, an axle tube portion disposed on the base, and a receiving portion. The impeller is disposed on the axle tube portion. The receiving portion includes plural third blades disposed around the base corresponding to the central area. The first and third blades are matched to each other to be assembled for transforming a tangent velocity into a static pressure to increase the pressure generated by the central area.

Abstract: An impeller comprises a hub and a plurality of blades surrounding the hub. The hub comprises a shaft. Each blade includes a leading edge, an outer edge, a middle portion and a trailing edge. The leading edge, the outer edge and the trailing edge are around three sides of the middle portion. From the hub outwardly shaft, the height of the leading edge to the horizontal plane of the lowest of the blade gradually decreases first and then gradually increases.